Move libata to drivers/ata.

1 files changed, 6097 insertions, 0 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
new file mode 100644
index 000000000000..7d786fba4d82
--- /dev/null
+++ b/drivers/ata/libata-core.c
@@ -0,0 +1,6097 @@
+/*
+ *  libata-core.c - helper library for ATA
+ *
+ *  Maintained by:  Jeff Garzik <jgarzik@pobox.com>
+ *    		    Please ALWAYS copy linux-ide@vger.kernel.org
+ *		    on emails.
+ *
+ *  Copyright 2003-2004 Red Hat, Inc.  All rights reserved.
+ *  Copyright 2003-2004 Jeff Garzik
+ *
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2, or (at your option)
+ *  any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; see the file COPYING.  If not, write to
+ *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ *
+ *  libata documentation is available via 'make {ps|pdf}docs',
+ *  as Documentation/DocBook/libata.*
+ *
+ *  Hardware documentation available from http://www.t13.org/ and
+ *  http://www.sata-io.org/
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/mm.h>
+#include <linux/highmem.h>
+#include <linux/spinlock.h>
+#include <linux/blkdev.h>
+#include <linux/delay.h>
+#include <linux/timer.h>
+#include <linux/interrupt.h>
+#include <linux/completion.h>
+#include <linux/suspend.h>
+#include <linux/workqueue.h>
+#include <linux/jiffies.h>
+#include <linux/scatterlist.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_host.h>
+#include <linux/libata.h>
+#include <asm/io.h>
+#include <asm/semaphore.h>
+#include <asm/byteorder.h>
+
+#include "libata.h"
+
+/* debounce timing parameters in msecs { interval, duration, timeout } */
+const unsigned long sata_deb_timing_normal[]		= {   5,  100, 2000 };
+const unsigned long sata_deb_timing_hotplug[]		= {  25,  500, 2000 };
+const unsigned long sata_deb_timing_long[]		= { 100, 2000, 5000 };
+
+static unsigned int ata_dev_init_params(struct ata_device *dev,
+					u16 heads, u16 sectors);
+static unsigned int ata_dev_set_xfermode(struct ata_device *dev);
+static void ata_dev_xfermask(struct ata_device *dev);
+
+static unsigned int ata_unique_id = 1;
+static struct workqueue_struct *ata_wq;
+
+struct workqueue_struct *ata_aux_wq;
+
+int atapi_enabled = 1;
+module_param(atapi_enabled, int, 0444);
+MODULE_PARM_DESC(atapi_enabled, "Enable discovery of ATAPI devices (0=off, 1=on)");
+
+int atapi_dmadir = 0;
+module_param(atapi_dmadir, int, 0444);
+MODULE_PARM_DESC(atapi_dmadir, "Enable ATAPI DMADIR bridge support (0=off, 1=on)");
+
+int libata_fua = 0;
+module_param_named(fua, libata_fua, int, 0444);
+MODULE_PARM_DESC(fua, "FUA support (0=off, 1=on)");
+
+static int ata_probe_timeout = ATA_TMOUT_INTERNAL / HZ;
+module_param(ata_probe_timeout, int, 0444);
+MODULE_PARM_DESC(ata_probe_timeout, "Set ATA probing timeout (seconds)");
+
+MODULE_AUTHOR("Jeff Garzik");
+MODULE_DESCRIPTION("Library module for ATA devices");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRV_VERSION);
+
+
+/**
+ *	ata_tf_to_fis - Convert ATA taskfile to SATA FIS structure
+ *	@tf: Taskfile to convert
+ *	@fis: Buffer into which data will output
+ *	@pmp: Port multiplier port
+ *
+ *	Converts a standard ATA taskfile to a Serial ATA
+ *	FIS structure (Register - Host to Device).
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ */
+
+void ata_tf_to_fis(const struct ata_taskfile *tf, u8 *fis, u8 pmp)
+{
+	fis[0] = 0x27;	/* Register - Host to Device FIS */
+	fis[1] = (pmp & 0xf) | (1 << 7); /* Port multiplier number,
+					    bit 7 indicates Command FIS */
+	fis[2] = tf->command;
+	fis[3] = tf->feature;
+
+	fis[4] = tf->lbal;
+	fis[5] = tf->lbam;
+	fis[6] = tf->lbah;
+	fis[7] = tf->device;
+
+	fis[8] = tf->hob_lbal;
+	fis[9] = tf->hob_lbam;
+	fis[10] = tf->hob_lbah;
+	fis[11] = tf->hob_feature;
+
+	fis[12] = tf->nsect;
+	fis[13] = tf->hob_nsect;
+	fis[14] = 0;
+	fis[15] = tf->ctl;
+
+	fis[16] = 0;
+	fis[17] = 0;
+	fis[18] = 0;
+	fis[19] = 0;
+}
+
+/**
+ *	ata_tf_from_fis - Convert SATA FIS to ATA taskfile
+ *	@fis: Buffer from which data will be input
+ *	@tf: Taskfile to output
+ *
+ *	Converts a serial ATA FIS structure to a standard ATA taskfile.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ */
+
+void ata_tf_from_fis(const u8 *fis, struct ata_taskfile *tf)
+{
+	tf->command	= fis[2];	/* status */
+	tf->feature	= fis[3];	/* error */
+
+	tf->lbal	= fis[4];
+	tf->lbam	= fis[5];
+	tf->lbah	= fis[6];
+	tf->device	= fis[7];
+
+	tf->hob_lbal	= fis[8];
+	tf->hob_lbam	= fis[9];
+	tf->hob_lbah	= fis[10];
+
+	tf->nsect	= fis[12];
+	tf->hob_nsect	= fis[13];
+}
+
+static const u8 ata_rw_cmds[] = {
+	/* pio multi */
+	ATA_CMD_READ_MULTI,
+	ATA_CMD_WRITE_MULTI,
+	ATA_CMD_READ_MULTI_EXT,
+	ATA_CMD_WRITE_MULTI_EXT,
+	0,
+	0,
+	0,
+	ATA_CMD_WRITE_MULTI_FUA_EXT,
+	/* pio */
+	ATA_CMD_PIO_READ,
+	ATA_CMD_PIO_WRITE,
+	ATA_CMD_PIO_READ_EXT,
+	ATA_CMD_PIO_WRITE_EXT,
+	0,
+	0,
+	0,
+	0,
+	/* dma */
+	ATA_CMD_READ,
+	ATA_CMD_WRITE,
+	ATA_CMD_READ_EXT,
+	ATA_CMD_WRITE_EXT,
+	0,
+	0,
+	0,
+	ATA_CMD_WRITE_FUA_EXT
+};
+
+/**
+ *	ata_rwcmd_protocol - set taskfile r/w commands and protocol
+ *	@qc: command to examine and configure
+ *
+ *	Examine the device configuration and tf->flags to calculate
+ *	the proper read/write commands and protocol to use.
+ *
+ *	LOCKING:
+ *	caller.
+ */
+int ata_rwcmd_protocol(struct ata_queued_cmd *qc)
+{
+	struct ata_taskfile *tf = &qc->tf;
+	struct ata_device *dev = qc->dev;
+	u8 cmd;
+
+	int index, fua, lba48, write;
+
+	fua = (tf->flags & ATA_TFLAG_FUA) ? 4 : 0;
+	lba48 = (tf->flags & ATA_TFLAG_LBA48) ? 2 : 0;
+	write = (tf->flags & ATA_TFLAG_WRITE) ? 1 : 0;
+
+	if (dev->flags & ATA_DFLAG_PIO) {
+		tf->protocol = ATA_PROT_PIO;
+		index = dev->multi_count ? 0 : 8;
+	} else if (lba48 && (qc->ap->flags & ATA_FLAG_PIO_LBA48)) {
+		/* Unable to use DMA due to host limitation */
+		tf->protocol = ATA_PROT_PIO;
+		index = dev->multi_count ? 0 : 8;
+	} else {
+		tf->protocol = ATA_PROT_DMA;
+		index = 16;
+	}
+
+	cmd = ata_rw_cmds[index + fua + lba48 + write];
+	if (cmd) {
+		tf->command = cmd;
+		return 0;
+	}
+	return -1;
+}
+
+/**
+ *	ata_pack_xfermask - Pack pio, mwdma and udma masks into xfer_mask
+ *	@pio_mask: pio_mask
+ *	@mwdma_mask: mwdma_mask
+ *	@udma_mask: udma_mask
+ *
+ *	Pack @pio_mask, @mwdma_mask and @udma_mask into a single
+ *	unsigned int xfer_mask.
+ *
+ *	LOCKING:
+ *	None.
+ *
+ *	RETURNS:
+ *	Packed xfer_mask.
+ */
+static unsigned int ata_pack_xfermask(unsigned int pio_mask,
+				      unsigned int mwdma_mask,
+				      unsigned int udma_mask)
+{
+	return ((pio_mask << ATA_SHIFT_PIO) & ATA_MASK_PIO) |
+		((mwdma_mask << ATA_SHIFT_MWDMA) & ATA_MASK_MWDMA) |
+		((udma_mask << ATA_SHIFT_UDMA) & ATA_MASK_UDMA);
+}
+
+/**
+ *	ata_unpack_xfermask - Unpack xfer_mask into pio, mwdma and udma masks
+ *	@xfer_mask: xfer_mask to unpack
+ *	@pio_mask: resulting pio_mask
+ *	@mwdma_mask: resulting mwdma_mask
+ *	@udma_mask: resulting udma_mask
+ *
+ *	Unpack @xfer_mask into @pio_mask, @mwdma_mask and @udma_mask.
+ *	Any NULL distination masks will be ignored.
+ */
+static void ata_unpack_xfermask(unsigned int xfer_mask,
+				unsigned int *pio_mask,
+				unsigned int *mwdma_mask,
+				unsigned int *udma_mask)
+{
+	if (pio_mask)
+		*pio_mask = (xfer_mask & ATA_MASK_PIO) >> ATA_SHIFT_PIO;
+	if (mwdma_mask)
+		*mwdma_mask = (xfer_mask & ATA_MASK_MWDMA) >> ATA_SHIFT_MWDMA;
+	if (udma_mask)
+		*udma_mask = (xfer_mask & ATA_MASK_UDMA) >> ATA_SHIFT_UDMA;
+}
+
+static const struct ata_xfer_ent {
+	int shift, bits;
+	u8 base;
+} ata_xfer_tbl[] = {
+	{ ATA_SHIFT_PIO, ATA_BITS_PIO, XFER_PIO_0 },
+	{ ATA_SHIFT_MWDMA, ATA_BITS_MWDMA, XFER_MW_DMA_0 },
+	{ ATA_SHIFT_UDMA, ATA_BITS_UDMA, XFER_UDMA_0 },
+	{ -1, },
+};
+
+/**
+ *	ata_xfer_mask2mode - Find matching XFER_* for the given xfer_mask
+ *	@xfer_mask: xfer_mask of interest
+ *
+ *	Return matching XFER_* value for @xfer_mask.  Only the highest
+ *	bit of @xfer_mask is considered.
+ *
+ *	LOCKING:
+ *	None.
+ *
+ *	RETURNS:
+ *	Matching XFER_* value, 0 if no match found.
+ */
+static u8 ata_xfer_mask2mode(unsigned int xfer_mask)
+{
+	int highbit = fls(xfer_mask) - 1;
+	const struct ata_xfer_ent *ent;
+
+	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
+		if (highbit >= ent->shift && highbit < ent->shift + ent->bits)
+			return ent->base + highbit - ent->shift;
+	return 0;
+}
+
+/**
+ *	ata_xfer_mode2mask - Find matching xfer_mask for XFER_*
+ *	@xfer_mode: XFER_* of interest
+ *
+ *	Return matching xfer_mask for @xfer_mode.
+ *
+ *	LOCKING:
+ *	None.
+ *
+ *	RETURNS:
+ *	Matching xfer_mask, 0 if no match found.
+ */
+static unsigned int ata_xfer_mode2mask(u8 xfer_mode)
+{
+	const struct ata_xfer_ent *ent;
+
+	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
+		if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
+			return 1 << (ent->shift + xfer_mode - ent->base);
+	return 0;
+}
+
+/**
+ *	ata_xfer_mode2shift - Find matching xfer_shift for XFER_*
+ *	@xfer_mode: XFER_* of interest
+ *
+ *	Return matching xfer_shift for @xfer_mode.
+ *
+ *	LOCKING:
+ *	None.
+ *
+ *	RETURNS:
+ *	Matching xfer_shift, -1 if no match found.
+ */
+static int ata_xfer_mode2shift(unsigned int xfer_mode)
+{
+	const struct ata_xfer_ent *ent;
+
+	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
+		if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
+			return ent->shift;
+	return -1;
+}
+
+/**
+ *	ata_mode_string - convert xfer_mask to string
+ *	@xfer_mask: mask of bits supported; only highest bit counts.
+ *
+ *	Determine string which represents the highest speed
+ *	(highest bit in @modemask).
+ *
+ *	LOCKING:
+ *	None.
+ *
+ *	RETURNS:
+ *	Constant C string representing highest speed listed in
+ *	@mode_mask, or the constant C string "<n/a>".
+ */
+static const char *ata_mode_string(unsigned int xfer_mask)
+{
+	static const char * const xfer_mode_str[] = {
+		"PIO0",
+		"PIO1",
+		"PIO2",
+		"PIO3",
+		"PIO4",
+		"MWDMA0",
+		"MWDMA1",
+		"MWDMA2",
+		"UDMA/16",
+		"UDMA/25",
+		"UDMA/33",
+		"UDMA/44",
+		"UDMA/66",
+		"UDMA/100",
+		"UDMA/133",
+		"UDMA7",
+	};
+	int highbit;
+
+	highbit = fls(xfer_mask) - 1;
+	if (highbit >= 0 && highbit < ARRAY_SIZE(xfer_mode_str))
+		return xfer_mode_str[highbit];
+	return "<n/a>";
+}
+
+static const char *sata_spd_string(unsigned int spd)
+{
+	static const char * const spd_str[] = {
+		"1.5 Gbps",
+		"3.0 Gbps",
+	};
+
+	if (spd == 0 || (spd - 1) >= ARRAY_SIZE(spd_str))
+		return "<unknown>";
+	return spd_str[spd - 1];
+}
+
+void ata_dev_disable(struct ata_device *dev)
+{
+	if (ata_dev_enabled(dev) && ata_msg_drv(dev->ap)) {
+		ata_dev_printk(dev, KERN_WARNING, "disabled\n");
+		dev->class++;
+	}
+}
+
+/**
+ *	ata_pio_devchk - PATA device presence detection
+ *	@ap: ATA channel to examine
+ *	@device: Device to examine (starting at zero)
+ *
+ *	This technique was originally described in
+ *	Hale Landis's ATADRVR (www.ata-atapi.com), and
+ *	later found its way into the ATA/ATAPI spec.
+ *
+ *	Write a pattern to the ATA shadow registers,
+ *	and if a device is present, it will respond by
+ *	correctly storing and echoing back the
+ *	ATA shadow register contents.
+ *
+ *	LOCKING:
+ *	caller.
+ */
+
+static unsigned int ata_pio_devchk(struct ata_port *ap,
+				   unsigned int device)
+{
+	struct ata_ioports *ioaddr = &ap->ioaddr;
+	u8 nsect, lbal;
+
+	ap->ops->dev_select(ap, device);
+
+	outb(0x55, ioaddr->nsect_addr);
+	outb(0xaa, ioaddr->lbal_addr);
+
+	outb(0xaa, ioaddr->nsect_addr);
+	outb(0x55, ioaddr->lbal_addr);
+
+	outb(0x55, ioaddr->nsect_addr);
+	outb(0xaa, ioaddr->lbal_addr);
+
+	nsect = inb(ioaddr->nsect_addr);
+	lbal = inb(ioaddr->lbal_addr);
+
+	if ((nsect == 0x55) && (lbal == 0xaa))
+		return 1;	/* we found a device */
+
+	return 0;		/* nothing found */
+}
+
+/**
+ *	ata_mmio_devchk - PATA device presence detection
+ *	@ap: ATA channel to examine
+ *	@device: Device to examine (starting at zero)
+ *
+ *	This technique was originally described in
+ *	Hale Landis's ATADRVR (www.ata-atapi.com), and
+ *	later found its way into the ATA/ATAPI spec.
+ *
+ *	Write a pattern to the ATA shadow registers,
+ *	and if a device is present, it will respond by
+ *	correctly storing and echoing back the
+ *	ATA shadow register contents.
+ *
+ *	LOCKING:
+ *	caller.
+ */
+
+static unsigned int ata_mmio_devchk(struct ata_port *ap,
+				    unsigned int device)
+{
+	struct ata_ioports *ioaddr = &ap->ioaddr;
+	u8 nsect, lbal;
+
+	ap->ops->dev_select(ap, device);
+
+	writeb(0x55, (void __iomem *) ioaddr->nsect_addr);
+	writeb(0xaa, (void __iomem *) ioaddr->lbal_addr);
+
+	writeb(0xaa, (void __iomem *) ioaddr->nsect_addr);
+	writeb(0x55, (void __iomem *) ioaddr->lbal_addr);
+
+	writeb(0x55, (void __iomem *) ioaddr->nsect_addr);
+	writeb(0xaa, (void __iomem *) ioaddr->lbal_addr);
+
+	nsect = readb((void __iomem *) ioaddr->nsect_addr);
+	lbal = readb((void __iomem *) ioaddr->lbal_addr);
+
+	if ((nsect == 0x55) && (lbal == 0xaa))
+		return 1;	/* we found a device */
+
+	return 0;		/* nothing found */
+}
+
+/**
+ *	ata_devchk - PATA device presence detection
+ *	@ap: ATA channel to examine
+ *	@device: Device to examine (starting at zero)
+ *
+ *	Dispatch ATA device presence detection, depending
+ *	on whether we are using PIO or MMIO to talk to the
+ *	ATA shadow registers.
+ *
+ *	LOCKING:
+ *	caller.
+ */
+
+static unsigned int ata_devchk(struct ata_port *ap,
+				    unsigned int device)
+{
+	if (ap->flags & ATA_FLAG_MMIO)
+		return ata_mmio_devchk(ap, device);
+	return ata_pio_devchk(ap, device);
+}
+
+/**
+ *	ata_dev_classify - determine device type based on ATA-spec signature
+ *	@tf: ATA taskfile register set for device to be identified
+ *
+ *	Determine from taskfile register contents whether a device is
+ *	ATA or ATAPI, as per "Signature and persistence" section
+ *	of ATA/PI spec (volume 1, sect 5.14).
+ *
+ *	LOCKING:
+ *	None.
+ *
+ *	RETURNS:
+ *	Device type, %ATA_DEV_ATA, %ATA_DEV_ATAPI, or %ATA_DEV_UNKNOWN
+ *	the event of failure.
+ */
+
+unsigned int ata_dev_classify(const struct ata_taskfile *tf)
+{
+	/* Apple's open source Darwin code hints that some devices only
+	 * put a proper signature into the LBA mid/high registers,
+	 * So, we only check those.  It's sufficient for uniqueness.
+	 */
+
+	if (((tf->lbam == 0) && (tf->lbah == 0)) ||
+	    ((tf->lbam == 0x3c) && (tf->lbah == 0xc3))) {
+		DPRINTK("found ATA device by sig\n");
+		return ATA_DEV_ATA;
+	}
+
+	if (((tf->lbam == 0x14) && (tf->lbah == 0xeb)) ||
+	    ((tf->lbam == 0x69) && (tf->lbah == 0x96))) {
+		DPRINTK("found ATAPI device by sig\n");
+		return ATA_DEV_ATAPI;
+	}
+
+	DPRINTK("unknown device\n");
+	return ATA_DEV_UNKNOWN;
+}
+
+/**
+ *	ata_dev_try_classify - Parse returned ATA device signature
+ *	@ap: ATA channel to examine
+ *	@device: Device to examine (starting at zero)
+ *	@r_err: Value of error register on completion
+ *
+ *	After an event -- SRST, E.D.D., or SATA COMRESET -- occurs,
+ *	an ATA/ATAPI-defined set of values is placed in the ATA
+ *	shadow registers, indicating the results of device detection
+ *	and diagnostics.
+ *
+ *	Select the ATA device, and read the values from the ATA shadow
+ *	registers.  Then parse according to the Error register value,
+ *	and the spec-defined values examined by ata_dev_classify().
+ *
+ *	LOCKING:
+ *	caller.
+ *
+ *	RETURNS:
+ *	Device type - %ATA_DEV_ATA, %ATA_DEV_ATAPI or %ATA_DEV_NONE.
+ */
+
+static unsigned int
+ata_dev_try_classify(struct ata_port *ap, unsigned int device, u8 *r_err)
+{
+	struct ata_taskfile tf;
+	unsigned int class;
+	u8 err;
+
+	ap->ops->dev_select(ap, device);
+
+	memset(&tf, 0, sizeof(tf));
+
+	ap->ops->tf_read(ap, &tf);
+	err = tf.feature;
+	if (r_err)
+		*r_err = err;
+
+	/* see if device passed diags */
+	if (err == 1)
+		/* do nothing */ ;
+	else if ((device == 0) && (err == 0x81))
+		/* do nothing */ ;
+	else
+		return ATA_DEV_NONE;
+
+	/* determine if device is ATA or ATAPI */
+	class = ata_dev_classify(&tf);
+
+	if (class == ATA_DEV_UNKNOWN)
+		return ATA_DEV_NONE;
+	if ((class == ATA_DEV_ATA) && (ata_chk_status(ap) == 0))
+		return ATA_DEV_NONE;
+	return class;
+}
+
+/**
+ *	ata_id_string - Convert IDENTIFY DEVICE page into string
+ *	@id: IDENTIFY DEVICE results we will examine
+ *	@s: string into which data is output
+ *	@ofs: offset into identify device page
+ *	@len: length of string to return. must be an even number.
+ *
+ *	The strings in the IDENTIFY DEVICE page are broken up into
+ *	16-bit chunks.  Run through the string, and output each
+ *	8-bit chunk linearly, regardless of platform.
+ *
+ *	LOCKING:
+ *	caller.
+ */
+
+void ata_id_string(const u16 *id, unsigned char *s,
+		   unsigned int ofs, unsigned int len)
+{
+	unsigned int c;
+
+	while (len > 0) {
+		c = id[ofs] >> 8;
+		*s = c;
+		s++;
+
+		c = id[ofs] & 0xff;
+		*s = c;
+		s++;
+
+		ofs++;
+		len -= 2;
+	}
+}
+
+/**
+ *	ata_id_c_string - Convert IDENTIFY DEVICE page into C string
+ *	@id: IDENTIFY DEVICE results we will examine
+ *	@s: string into which data is output
+ *	@ofs: offset into identify device page
+ *	@len: length of string to return. must be an odd number.
+ *
+ *	This function is identical to ata_id_string except that it
+ *	trims trailing spaces and terminates the resulting string with
+ *	null.  @len must be actual maximum length (even number) + 1.
+ *
+ *	LOCKING:
+ *	caller.
+ */
+void ata_id_c_string(const u16 *id, unsigned char *s,
+		     unsigned int ofs, unsigned int len)
+{
+	unsigned char *p;
+
+	WARN_ON(!(len & 1));
+
+	ata_id_string(id, s, ofs, len - 1);
+
+	p = s + strnlen(s, len - 1);
+	while (p > s && p[-1] == ' ')
+		p--;
+	*p = '\0';
+}
+
+static u64 ata_id_n_sectors(const u16 *id)
+{
+	if (ata_id_has_lba(id)) {
+		if (ata_id_has_lba48(id))
+			return ata_id_u64(id, 100);
+		else
+			return ata_id_u32(id, 60);
+	} else {
+		if (ata_id_current_chs_valid(id))
+			return ata_id_u32(id, 57);
+		else
+			return id[1] * id[3] * id[6];
+	}
+}
+
+/**
+ *	ata_noop_dev_select - Select device 0/1 on ATA bus
+ *	@ap: ATA channel to manipulate
+ *	@device: ATA device (numbered from zero) to select
+ *
+ *	This function performs no actual function.
+ *
+ *	May be used as the dev_select() entry in ata_port_operations.
+ *
+ *	LOCKING:
+ *	caller.
+ */
+void ata_noop_dev_select (struct ata_port *ap, unsigned int device)
+{
+}
+
+
+/**
+ *	ata_std_dev_select - Select device 0/1 on ATA bus
+ *	@ap: ATA channel to manipulate
+ *	@device: ATA device (numbered from zero) to select
+ *
+ *	Use the method defined in the ATA specification to
+ *	make either device 0, or device 1, active on the
+ *	ATA channel.  Works with both PIO and MMIO.
+ *
+ *	May be used as the dev_select() entry in ata_port_operations.
+ *
+ *	LOCKING:
+ *	caller.
+ */
+
+void ata_std_dev_select (struct ata_port *ap, unsigned int device)
+{
+	u8 tmp;
+
+	if (device == 0)
+		tmp = ATA_DEVICE_OBS;
+	else
+		tmp = ATA_DEVICE_OBS | ATA_DEV1;
+
+	if (ap->flags & ATA_FLAG_MMIO) {
+		writeb(tmp, (void __iomem *) ap->ioaddr.device_addr);
+	} else {
+		outb(tmp, ap->ioaddr.device_addr);
+	}
+	ata_pause(ap);		/* needed; also flushes, for mmio */
+}
+
+/**
+ *	ata_dev_select - Select device 0/1 on ATA bus
+ *	@ap: ATA channel to manipulate
+ *	@device: ATA device (numbered from zero) to select
+ *	@wait: non-zero to wait for Status register BSY bit to clear
+ *	@can_sleep: non-zero if context allows sleeping
+ *
+ *	Use the method defined in the ATA specification to
+ *	make either device 0, or device 1, active on the
+ *	ATA channel.
+ *
+ *	This is a high-level version of ata_std_dev_select(),
+ *	which additionally provides the services of inserting
+ *	the proper pauses and status polling, where needed.
+ *
+ *	LOCKING:
+ *	caller.
+ */
+
+void ata_dev_select(struct ata_port *ap, unsigned int device,
+			   unsigned int wait, unsigned int can_sleep)
+{
+	if (ata_msg_probe(ap))
+		ata_port_printk(ap, KERN_INFO, "ata_dev_select: ENTER, ata%u: "
+				"device %u, wait %u\n", ap->id, device, wait);
+
+	if (wait)
+		ata_wait_idle(ap);
+
+	ap->ops->dev_select(ap, device);
+
+	if (wait) {
+		if (can_sleep && ap->device[device].class == ATA_DEV_ATAPI)
+			msleep(150);
+		ata_wait_idle(ap);
+	}
+}
+
+/**
+ *	ata_dump_id - IDENTIFY DEVICE info debugging output
+ *	@id: IDENTIFY DEVICE page to dump
+ *
+ *	Dump selected 16-bit words from the given IDENTIFY DEVICE
+ *	page.
+ *
+ *	LOCKING:
+ *	caller.
+ */
+
+static inline void ata_dump_id(const u16 *id)
+{
+	DPRINTK("49==0x%04x  "
+		"53==0x%04x  "
+		"63==0x%04x  "
+		"64==0x%04x  "
+		"75==0x%04x  \n",
+		id[49],
+		id[53],
+		id[63],
+		id[64],
+		id[75]);
+	DPRINTK("80==0x%04x  "
+		"81==0x%04x  "
+		"82==0x%04x  "
+		"83==0x%04x  "
+		"84==0x%04x  \n",
+		id[80],
+		id[81],
+		id[82],
+		id[83],
+		id[84]);
+	DPRINTK("88==0x%04x  "
+		"93==0x%04x\n",
+		id[88],
+		id[93]);
+}
+
+/**
+ *	ata_id_xfermask - Compute xfermask from the given IDENTIFY data
+ *	@id: IDENTIFY data to compute xfer mask from
+ *
+ *	Compute the xfermask for this device. This is not as trivial
+ *	as it seems if we must consider early devices correctly.
+ *
+ *	FIXME: pre IDE drive timing (do we care ?).
+ *
+ *	LOCKING:
+ *	None.
+ *
+ *	RETURNS:
+ *	Computed xfermask
+ */
+static unsigned int ata_id_xfermask(const u16 *id)
+{
+	unsigned int pio_mask, mwdma_mask, udma_mask;
+
+	/* Usual case. Word 53 indicates word 64 is valid */
+	if (id[ATA_ID_FIELD_VALID] & (1 << 1)) {
+		pio_mask = id[ATA_ID_PIO_MODES] & 0x03;
+		pio_mask <<= 3;
+		pio_mask |= 0x7;
+	} else {
+		/* If word 64 isn't valid then Word 51 high byte holds
+		 * the PIO timing number for the maximum. Turn it into
+		 * a mask.
+		 */
+		pio_mask = (2 << (id[ATA_ID_OLD_PIO_MODES] & 0xFF)) - 1 ;
+
+		/* But wait.. there's more. Design your standards by
+		 * committee and you too can get a free iordy field to
+		 * process. However its the speeds not the modes that
+		 * are supported... Note drivers using the timing API
+		 * will get this right anyway
+		 */
+	}
+
+	mwdma_mask = id[ATA_ID_MWDMA_MODES] & 0x07;
+
+	udma_mask = 0;
+	if (id[ATA_ID_FIELD_VALID] & (1 << 2))
+		udma_mask = id[ATA_ID_UDMA_MODES] & 0xff;
+
+	return ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
+}
+
+/**
+ *	ata_port_queue_task - Queue port_task
+ *	@ap: The ata_port to queue port_task for
+ *	@fn: workqueue function to be scheduled
+ *	@data: data value to pass to workqueue function
+ *	@delay: delay time for workqueue function
+ *
+ *	Schedule @fn(@data) for execution after @delay jiffies using
+ *	port_task.  There is one port_task per port and it's the
+ *	user(low level driver)'s responsibility to make sure that only
+ *	one task is active at any given time.
+ *
+ *	libata core layer takes care of synchronization between
+ *	port_task and EH.  ata_port_queue_task() may be ignored for EH
+ *	synchronization.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ */
+void ata_port_queue_task(struct ata_port *ap, void (*fn)(void *), void *data,
+			 unsigned long delay)
+{
+	int rc;
+
+	if (ap->pflags & ATA_PFLAG_FLUSH_PORT_TASK)
+		return;
+
+	PREPARE_WORK(&ap->port_task, fn, data);
+
+	if (!delay)
+		rc = queue_work(ata_wq, &ap->port_task);
+	else
+		rc = queue_delayed_work(ata_wq, &ap->port_task, delay);
+
+	/* rc == 0 means that another user is using port task */
+	WARN_ON(rc == 0);
+}
+
+/**
+ *	ata_port_flush_task - Flush port_task
+ *	@ap: The ata_port to flush port_task for
+ *
+ *	After this function completes, port_task is guranteed not to
+ *	be running or scheduled.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep)
+ */
+void ata_port_flush_task(struct ata_port *ap)
+{
+	unsigned long flags;
+
+	DPRINTK("ENTER\n");
+
+	spin_lock_irqsave(ap->lock, flags);
+	ap->pflags |= ATA_PFLAG_FLUSH_PORT_TASK;
+	spin_unlock_irqrestore(ap->lock, flags);
+
+	DPRINTK("flush #1\n");
+	flush_workqueue(ata_wq);
+
+	/*
+	 * At this point, if a task is running, it's guaranteed to see
+	 * the FLUSH flag; thus, it will never queue pio tasks again.
+	 * Cancel and flush.
+	 */
+	if (!cancel_delayed_work(&ap->port_task)) {
+		if (ata_msg_ctl(ap))
+			ata_port_printk(ap, KERN_DEBUG, "%s: flush #2\n",
+					__FUNCTION__);
+		flush_workqueue(ata_wq);
+	}
+
+	spin_lock_irqsave(ap->lock, flags);
+	ap->pflags &= ~ATA_PFLAG_FLUSH_PORT_TASK;
+	spin_unlock_irqrestore(ap->lock, flags);
+
+	if (ata_msg_ctl(ap))
+		ata_port_printk(ap, KERN_DEBUG, "%s: EXIT\n", __FUNCTION__);
+}
+
+void ata_qc_complete_internal(struct ata_queued_cmd *qc)
+{
+	struct completion *waiting = qc->private_data;
+
+	complete(waiting);
+}
+
+/**
+ *	ata_exec_internal - execute libata internal command
+ *	@dev: Device to which the command is sent
+ *	@tf: Taskfile registers for the command and the result
+ *	@cdb: CDB for packet command
+ *	@dma_dir: Data tranfer direction of the command
+ *	@buf: Data buffer of the command
+ *	@buflen: Length of data buffer
+ *
+ *	Executes libata internal command with timeout.  @tf contains
+ *	command on entry and result on return.  Timeout and error
+ *	conditions are reported via return value.  No recovery action
+ *	is taken after a command times out.  It's caller's duty to
+ *	clean up after timeout.
+ *
+ *	LOCKING:
+ *	None.  Should be called with kernel context, might sleep.
+ *
+ *	RETURNS:
+ *	Zero on success, AC_ERR_* mask on failure
+ */
+unsigned ata_exec_internal(struct ata_device *dev,
+			   struct ata_taskfile *tf, const u8 *cdb,
+			   int dma_dir, void *buf, unsigned int buflen)
+{
+	struct ata_port *ap = dev->ap;
+	u8 command = tf->command;
+	struct ata_queued_cmd *qc;
+	unsigned int tag, preempted_tag;
+	u32 preempted_sactive, preempted_qc_active;
+	DECLARE_COMPLETION_ONSTACK(wait);
+	unsigned long flags;
+	unsigned int err_mask;
+	int rc;
+
+	spin_lock_irqsave(ap->lock, flags);
+
+	/* no internal command while frozen */
+	if (ap->pflags & ATA_PFLAG_FROZEN) {
+		spin_unlock_irqrestore(ap->lock, flags);
+		return AC_ERR_SYSTEM;
+	}
+
+	/* initialize internal qc */
+
+	/* XXX: Tag 0 is used for drivers with legacy EH as some
+	 * drivers choke if any other tag is given.  This breaks
+	 * ata_tag_internal() test for those drivers.  Don't use new
+	 * EH stuff without converting to it.
+	 */
+	if (ap->ops->error_handler)
+		tag = ATA_TAG_INTERNAL;
+	else
+		tag = 0;
+
+	if (test_and_set_bit(tag, &ap->qc_allocated))
+		BUG();
+	qc = __ata_qc_from_tag(ap, tag);
+
+	qc->tag = tag;
+	qc->scsicmd = NULL;
+	qc->ap = ap;
+	qc->dev = dev;
+	ata_qc_reinit(qc);
+
+	preempted_tag = ap->active_tag;
+	preempted_sactive = ap->sactive;
+	preempted_qc_active = ap->qc_active;
+	ap->active_tag = ATA_TAG_POISON;
+	ap->sactive = 0;
+	ap->qc_active = 0;
+
+	/* prepare & issue qc */
+	qc->tf = *tf;
+	if (cdb)
+		memcpy(qc->cdb, cdb, ATAPI_CDB_LEN);
+	qc->flags |= ATA_QCFLAG_RESULT_TF;
+	qc->dma_dir = dma_dir;
+	if (dma_dir != DMA_NONE) {
+		ata_sg_init_one(qc, buf, buflen);
+		qc->nsect = buflen / ATA_SECT_SIZE;
+	}
+
+	qc->private_data = &wait;
+	qc->complete_fn = ata_qc_complete_internal;
+
+	ata_qc_issue(qc);
+
+	spin_unlock_irqrestore(ap->lock, flags);
+
+	rc = wait_for_completion_timeout(&wait, ata_probe_timeout);
+
+	ata_port_flush_task(ap);
+
+	if (!rc) {
+		spin_lock_irqsave(ap->lock, flags);
+
+		/* We're racing with irq here.  If we lose, the
+		 * following test prevents us from completing the qc
+		 * twice.  If we win, the port is frozen and will be
+		 * cleaned up by ->post_internal_cmd().
+		 */
+		if (qc->flags & ATA_QCFLAG_ACTIVE) {
+			qc->err_mask |= AC_ERR_TIMEOUT;
+
+			if (ap->ops->error_handler)
+				ata_port_freeze(ap);
+			else
+				ata_qc_complete(qc);
+
+			if (ata_msg_warn(ap))
+				ata_dev_printk(dev, KERN_WARNING,
+					"qc timeout (cmd 0x%x)\n", command);
+		}
+
+		spin_unlock_irqrestore(ap->lock, flags);
+	}
+
+	/* do post_internal_cmd */
+	if (ap->ops->post_internal_cmd)
+		ap->ops->post_internal_cmd(qc);
+
+	if (qc->flags & ATA_QCFLAG_FAILED && !qc->err_mask) {
+		if (ata_msg_warn(ap))
+			ata_dev_printk(dev, KERN_WARNING,
+				"zero err_mask for failed "
+				"internal command, assuming AC_ERR_OTHER\n");
+		qc->err_mask |= AC_ERR_OTHER;
+	}
+
+	/* finish up */
+	spin_lock_irqsave(ap->lock, flags);
+
+	*tf = qc->result_tf;
+	err_mask = qc->err_mask;
+
+	ata_qc_free(qc);
+	ap->active_tag = preempted_tag;
+	ap->sactive = preempted_sactive;
+	ap->qc_active = preempted_qc_active;
+
+	/* XXX - Some LLDDs (sata_mv) disable port on command failure.
+	 * Until those drivers are fixed, we detect the condition
+	 * here, fail the command with AC_ERR_SYSTEM and reenable the
+	 * port.
+	 *
+	 * Note that this doesn't change any behavior as internal
+	 * command failure results in disabling the device in the
+	 * higher layer for LLDDs without new reset/EH callbacks.
+	 *
+	 * Kill the following code as soon as those drivers are fixed.
+	 */
+	if (ap->flags & ATA_FLAG_DISABLED) {
+		err_mask |= AC_ERR_SYSTEM;
+		ata_port_probe(ap);
+	}
+
+	spin_unlock_irqrestore(ap->lock, flags);
+
+	return err_mask;
+}
+
+/**
+ *	ata_do_simple_cmd - execute simple internal command
+ *	@dev: Device to which the command is sent
+ *	@cmd: Opcode to execute
+ *
+ *	Execute a 'simple' command, that only consists of the opcode
+ *	'cmd' itself, without filling any other registers
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep).
+ *
+ *	RETURNS:
+ *	Zero on success, AC_ERR_* mask on failure
+ */
+unsigned int ata_do_simple_cmd(struct ata_device *dev, u8 cmd)
+{
+	struct ata_taskfile tf;
+
+	ata_tf_init(dev, &tf);
+
+	tf.command = cmd;
+	tf.flags |= ATA_TFLAG_DEVICE;
+	tf.protocol = ATA_PROT_NODATA;
+
+	return ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0);
+}
+
+/**
+ *	ata_pio_need_iordy	-	check if iordy needed
+ *	@adev: ATA device
+ *
+ *	Check if the current speed of the device requires IORDY. Used
+ *	by various controllers for chip configuration.
+ */
+
+unsigned int ata_pio_need_iordy(const struct ata_device *adev)
+{
+	int pio;
+	int speed = adev->pio_mode - XFER_PIO_0;
+
+	if (speed < 2)
+		return 0;
+	if (speed > 2)
+		return 1;
+
+	/* If we have no drive specific rule, then PIO 2 is non IORDY */
+
+	if (adev->id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE */
+		pio = adev->id[ATA_ID_EIDE_PIO];
+		/* Is the speed faster than the drive allows non IORDY ? */
+		if (pio) {
+			/* This is cycle times not frequency - watch the logic! */
+			if (pio > 240)	/* PIO2 is 240nS per cycle */
+				return 1;
+			return 0;
+		}
+	}
+	return 0;
+}
+
+/**
+ *	ata_dev_read_id - Read ID data from the specified device
+ *	@dev: target device
+ *	@p_class: pointer to class of the target device (may be changed)
+ *	@post_reset: is this read ID post-reset?
+ *	@id: buffer to read IDENTIFY data into
+ *
+ *	Read ID data from the specified device.  ATA_CMD_ID_ATA is
+ *	performed on ATA devices and ATA_CMD_ID_ATAPI on ATAPI
+ *	devices.  This function also issues ATA_CMD_INIT_DEV_PARAMS
+ *	for pre-ATA4 drives.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep)
+ *
+ *	RETURNS:
+ *	0 on success, -errno otherwise.
+ */
+int ata_dev_read_id(struct ata_device *dev, unsigned int *p_class,
+		    int post_reset, u16 *id)
+{
+	struct ata_port *ap = dev->ap;
+	unsigned int class = *p_class;
+	struct ata_taskfile tf;
+	unsigned int err_mask = 0;
+	const char *reason;
+	int rc;
+
+	if (ata_msg_ctl(ap))
+		ata_dev_printk(dev, KERN_DEBUG, "%s: ENTER, host %u, dev %u\n",
+			       __FUNCTION__, ap->id, dev->devno);
+
+	ata_dev_select(ap, dev->devno, 1, 1); /* select device 0/1 */
+
+ retry:
+	ata_tf_init(dev, &tf);
+
+	switch (class) {
+	case ATA_DEV_ATA:
+		tf.command = ATA_CMD_ID_ATA;
+		break;
+	case ATA_DEV_ATAPI:
+		tf.command = ATA_CMD_ID_ATAPI;
+		break;
+	default:
+		rc = -ENODEV;
+		reason = "unsupported class";
+		goto err_out;
+	}
+
+	tf.protocol = ATA_PROT_PIO;
+
+	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_FROM_DEVICE,
+				     id, sizeof(id[0]) * ATA_ID_WORDS);
+	if (err_mask) {
+		rc = -EIO;
+		reason = "I/O error";
+		goto err_out;
+	}
+
+	swap_buf_le16(id, ATA_ID_WORDS);
+
+	/* sanity check */
+	if ((class == ATA_DEV_ATA) != (ata_id_is_ata(id) | ata_id_is_cfa(id))) {
+		rc = -EINVAL;
+		reason = "device reports illegal type";
+		goto err_out;
+	}
+
+	if (post_reset && class == ATA_DEV_ATA) {
+		/*
+		 * The exact sequence expected by certain pre-ATA4 drives is:
+		 * SRST RESET
+		 * IDENTIFY
+		 * INITIALIZE DEVICE PARAMETERS
+		 * anything else..
+		 * Some drives were very specific about that exact sequence.
+		 */
+		if (ata_id_major_version(id) < 4 || !ata_id_has_lba(id)) {
+			err_mask = ata_dev_init_params(dev, id[3], id[6]);
+			if (err_mask) {
+				rc = -EIO;
+				reason = "INIT_DEV_PARAMS failed";
+				goto err_out;
+			}
+
+			/* current CHS translation info (id[53-58]) might be
+			 * changed. reread the identify device info.
+			 */
+			post_reset = 0;
+			goto retry;
+		}
+	}
+
+	*p_class = class;
+
+	return 0;
+
+ err_out:
+	if (ata_msg_warn(ap))
+		ata_dev_printk(dev, KERN_WARNING, "failed to IDENTIFY "
+			       "(%s, err_mask=0x%x)\n", reason, err_mask);
+	return rc;
+}
+
+static inline u8 ata_dev_knobble(struct ata_device *dev)
+{
+	return ((dev->ap->cbl == ATA_CBL_SATA) && (!ata_id_is_sata(dev->id)));
+}
+
+static void ata_dev_config_ncq(struct ata_device *dev,
+			       char *desc, size_t desc_sz)
+{
+	struct ata_port *ap = dev->ap;
+	int hdepth = 0, ddepth = ata_id_queue_depth(dev->id);
+
+	if (!ata_id_has_ncq(dev->id)) {
+		desc[0] = '\0';
+		return;
+	}
+
+	if (ap->flags & ATA_FLAG_NCQ) {
+		hdepth = min(ap->host->can_queue, ATA_MAX_QUEUE - 1);
+		dev->flags |= ATA_DFLAG_NCQ;
+	}
+
+	if (hdepth >= ddepth)
+		snprintf(desc, desc_sz, "NCQ (depth %d)", ddepth);
+	else
+		snprintf(desc, desc_sz, "NCQ (depth %d/%d)", hdepth, ddepth);
+}
+
+static void ata_set_port_max_cmd_len(struct ata_port *ap)
+{
+	int i;
+
+	if (ap->host) {
+		ap->host->max_cmd_len = 0;
+		for (i = 0; i < ATA_MAX_DEVICES; i++)
+			ap->host->max_cmd_len = max_t(unsigned int,
+						      ap->host->max_cmd_len,
+						      ap->device[i].cdb_len);
+	}
+}
+
+/**
+ *	ata_dev_configure - Configure the specified ATA/ATAPI device
+ *	@dev: Target device to configure
+ *	@print_info: Enable device info printout
+ *
+ *	Configure @dev according to @dev->id.  Generic and low-level
+ *	driver specific fixups are also applied.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep)
+ *
+ *	RETURNS:
+ *	0 on success, -errno otherwise
+ */
+int ata_dev_configure(struct ata_device *dev, int print_info)
+{
+	struct ata_port *ap = dev->ap;
+	const u16 *id = dev->id;
+	unsigned int xfer_mask;
+	int rc;
+
+	if (!ata_dev_enabled(dev) && ata_msg_info(ap)) {
+		ata_dev_printk(dev, KERN_INFO,
+			       "%s: ENTER/EXIT (host %u, dev %u) -- nodev\n",
+			       __FUNCTION__, ap->id, dev->devno);
+		return 0;
+	}
+
+	if (ata_msg_probe(ap))
+		ata_dev_printk(dev, KERN_DEBUG, "%s: ENTER, host %u, dev %u\n",
+			       __FUNCTION__, ap->id, dev->devno);
+
+	/* print device capabilities */
+	if (ata_msg_probe(ap))
+		ata_dev_printk(dev, KERN_DEBUG,
+			       "%s: cfg 49:%04x 82:%04x 83:%04x 84:%04x "
+			       "85:%04x 86:%04x 87:%04x 88:%04x\n",
+			       __FUNCTION__,
+			       id[49], id[82], id[83], id[84],
+			       id[85], id[86], id[87], id[88]);
+
+	/* initialize to-be-configured parameters */
+	dev->flags &= ~ATA_DFLAG_CFG_MASK;
+	dev->max_sectors = 0;
+	dev->cdb_len = 0;
+	dev->n_sectors = 0;
+	dev->cylinders = 0;
+	dev->heads = 0;
+	dev->sectors = 0;
+
+	/*
+	 * common ATA, ATAPI feature tests
+	 */
+
+	/* find max transfer mode; for printk only */
+	xfer_mask = ata_id_xfermask(id);
+
+	if (ata_msg_probe(ap))
+		ata_dump_id(id);
+
+	/* ATA-specific feature tests */
+	if (dev->class == ATA_DEV_ATA) {
+		dev->n_sectors = ata_id_n_sectors(id);
+
+		if (ata_id_has_lba(id)) {
+			const char *lba_desc;
+			char ncq_desc[20];
+
+			lba_desc = "LBA";
+			dev->flags |= ATA_DFLAG_LBA;
+			if (ata_id_has_lba48(id)) {
+				dev->flags |= ATA_DFLAG_LBA48;
+				lba_desc = "LBA48";
+			}
+
+			/* config NCQ */
+			ata_dev_config_ncq(dev, ncq_desc, sizeof(ncq_desc));
+
+			/* print device info to dmesg */
+			if (ata_msg_drv(ap) && print_info)
+				ata_dev_printk(dev, KERN_INFO, "ATA-%d, "
+					"max %s, %Lu sectors: %s %s\n",
+					ata_id_major_version(id),
+					ata_mode_string(xfer_mask),
+					(unsigned long long)dev->n_sectors,
+					lba_desc, ncq_desc);
+		} else {
+			/* CHS */
+
+			/* Default translation */
+			dev->cylinders	= id[1];
+			dev->heads	= id[3];
+			dev->sectors	= id[6];
+
+			if (ata_id_current_chs_valid(id)) {
+				/* Current CHS translation is valid. */
+				dev->cylinders = id[54];
+				dev->heads     = id[55];
+				dev->sectors   = id[56];
+			}
+
+			/* print device info to dmesg */
+			if (ata_msg_drv(ap) && print_info)
+				ata_dev_printk(dev, KERN_INFO, "ATA-%d, "
+					"max %s, %Lu sectors: CHS %u/%u/%u\n",
+					ata_id_major_version(id),
+					ata_mode_string(xfer_mask),
+					(unsigned long long)dev->n_sectors,
+					dev->cylinders, dev->heads,
+					dev->sectors);
+		}
+
+		if (dev->id[59] & 0x100) {
+			dev->multi_count = dev->id[59] & 0xff;
+			if (ata_msg_drv(ap) && print_info)
+				ata_dev_printk(dev, KERN_INFO,
+					"ata%u: dev %u multi count %u\n",
+					ap->id, dev->devno, dev->multi_count);
+		}
+
+		dev->cdb_len = 16;
+	}
+
+	/* ATAPI-specific feature tests */
+	else if (dev->class == ATA_DEV_ATAPI) {
+		char *cdb_intr_string = "";
+
+		rc = atapi_cdb_len(id);
+		if ((rc < 12) || (rc > ATAPI_CDB_LEN)) {
+			if (ata_msg_warn(ap))
+				ata_dev_printk(dev, KERN_WARNING,
+					       "unsupported CDB len\n");
+			rc = -EINVAL;
+			goto err_out_nosup;
+		}
+		dev->cdb_len = (unsigned int) rc;
+
+		if (ata_id_cdb_intr(dev->id)) {
+			dev->flags |= ATA_DFLAG_CDB_INTR;
+			cdb_intr_string = ", CDB intr";
+		}
+
+		/* print device info to dmesg */
+		if (ata_msg_drv(ap) && print_info)
+			ata_dev_printk(dev, KERN_INFO, "ATAPI, max %s%s\n",
+				       ata_mode_string(xfer_mask),
+				       cdb_intr_string);
+	}
+
+	ata_set_port_max_cmd_len(ap);
+
+	/* limit bridge transfers to udma5, 200 sectors */
+	if (ata_dev_knobble(dev)) {
+		if (ata_msg_drv(ap) && print_info)
+			ata_dev_printk(dev, KERN_INFO,
+				       "applying bridge limits\n");
+		dev->udma_mask &= ATA_UDMA5;
+		dev->max_sectors = ATA_MAX_SECTORS;
+	}
+
+	if (ap->ops->dev_config)
+		ap->ops->dev_config(ap, dev);
+
+	if (ata_msg_probe(ap))
+		ata_dev_printk(dev, KERN_DEBUG, "%s: EXIT, drv_stat = 0x%x\n",
+			__FUNCTION__, ata_chk_status(ap));
+	return 0;
+
+err_out_nosup:
+	if (ata_msg_probe(ap))
+		ata_dev_printk(dev, KERN_DEBUG,
+			       "%s: EXIT, err\n", __FUNCTION__);
+	return rc;
+}
+
+/**
+ *	ata_bus_probe - Reset and probe ATA bus
+ *	@ap: Bus to probe
+ *
+ *	Master ATA bus probing function.  Initiates a hardware-dependent
+ *	bus reset, then attempts to identify any devices found on
+ *	the bus.
+ *
+ *	LOCKING:
+ *	PCI/etc. bus probe sem.
+ *
+ *	RETURNS:
+ *	Zero on success, negative errno otherwise.
+ */
+
+int ata_bus_probe(struct ata_port *ap)
+{
+	unsigned int classes[ATA_MAX_DEVICES];
+	int tries[ATA_MAX_DEVICES];
+	int i, rc, down_xfermask;
+	struct ata_device *dev;
+
+	ata_port_probe(ap);
+
+	for (i = 0; i < ATA_MAX_DEVICES; i++)
+		tries[i] = ATA_PROBE_MAX_TRIES;
+
+ retry:
+	down_xfermask = 0;
+
+	/* reset and determine device classes */
+	ap->ops->phy_reset(ap);
+
+	for (i = 0; i < ATA_MAX_DEVICES; i++) {
+		dev = &ap->device[i];
+
+		if (!(ap->flags & ATA_FLAG_DISABLED) &&
+		    dev->class != ATA_DEV_UNKNOWN)
+			classes[dev->devno] = dev->class;
+		else
+			classes[dev->devno] = ATA_DEV_NONE;
+
+		dev->class = ATA_DEV_UNKNOWN;
+	}
+
+	ata_port_probe(ap);
+
+	/* after the reset the device state is PIO 0 and the controller
+	   state is undefined. Record the mode */
+
+	for (i = 0; i < ATA_MAX_DEVICES; i++)
+		ap->device[i].pio_mode = XFER_PIO_0;
+
+	/* read IDENTIFY page and configure devices */
+	for (i = 0; i < ATA_MAX_DEVICES; i++) {
+		dev = &ap->device[i];
+
+		if (tries[i])
+			dev->class = classes[i];
+
+		if (!ata_dev_enabled(dev))
+			continue;
+
+		rc = ata_dev_read_id(dev, &dev->class, 1, dev->id);
+		if (rc)
+			goto fail;
+
+		rc = ata_dev_configure(dev, 1);
+		if (rc)
+			goto fail;
+	}
+
+	/* configure transfer mode */
+	rc = ata_set_mode(ap, &dev);
+	if (rc) {
+		down_xfermask = 1;
+		goto fail;
+	}
+
+	for (i = 0; i < ATA_MAX_DEVICES; i++)
+		if (ata_dev_enabled(&ap->device[i]))
+			return 0;
+
+	/* no device present, disable port */
+	ata_port_disable(ap);
+	ap->ops->port_disable(ap);
+	return -ENODEV;
+
+ fail:
+	switch (rc) {
+	case -EINVAL:
+	case -ENODEV:
+		tries[dev->devno] = 0;
+		break;
+	case -EIO:
+		sata_down_spd_limit(ap);
+		/* fall through */
+	default:
+		tries[dev->devno]--;
+		if (down_xfermask &&
+		    ata_down_xfermask_limit(dev, tries[dev->devno] == 1))
+			tries[dev->devno] = 0;
+	}
+
+	if (!tries[dev->devno]) {
+		ata_down_xfermask_limit(dev, 1);
+		ata_dev_disable(dev);
+	}
+
+	goto retry;
+}
+
+/**
+ *	ata_port_probe - Mark port as enabled
+ *	@ap: Port for which we indicate enablement
+ *
+ *	Modify @ap data structure such that the system
+ *	thinks that the entire port is enabled.
+ *
+ *	LOCKING: host_set lock, or some other form of
+ *	serialization.
+ */
+
+void ata_port_probe(struct ata_port *ap)
+{
+	ap->flags &= ~ATA_FLAG_DISABLED;
+}
+
+/**
+ *	sata_print_link_status - Print SATA link status
+ *	@ap: SATA port to printk link status about
+ *
+ *	This function prints link speed and status of a SATA link.
+ *
+ *	LOCKING:
+ *	None.
+ */
+static void sata_print_link_status(struct ata_port *ap)
+{
+	u32 sstatus, scontrol, tmp;
+
+	if (sata_scr_read(ap, SCR_STATUS, &sstatus))
+		return;
+	sata_scr_read(ap, SCR_CONTROL, &scontrol);
+
+	if (ata_port_online(ap)) {
+		tmp = (sstatus >> 4) & 0xf;
+		ata_port_printk(ap, KERN_INFO,
+				"SATA link up %s (SStatus %X SControl %X)\n",
+				sata_spd_string(tmp), sstatus, scontrol);
+	} else {
+		ata_port_printk(ap, KERN_INFO,
+				"SATA link down (SStatus %X SControl %X)\n",
+				sstatus, scontrol);
+	}
+}
+
+/**
+ *	__sata_phy_reset - Wake/reset a low-level SATA PHY
+ *	@ap: SATA port associated with target SATA PHY.
+ *
+ *	This function issues commands to standard SATA Sxxx
+ *	PHY registers, to wake up the phy (and device), and
+ *	clear any reset condition.
+ *
+ *	LOCKING:
+ *	PCI/etc. bus probe sem.
+ *
+ */
+void __sata_phy_reset(struct ata_port *ap)
+{
+	u32 sstatus;
+	unsigned long timeout = jiffies + (HZ * 5);
+
+	if (ap->flags & ATA_FLAG_SATA_RESET) {
+		/* issue phy wake/reset */
+		sata_scr_write_flush(ap, SCR_CONTROL, 0x301);
+		/* Couldn't find anything in SATA I/II specs, but
+		 * AHCI-1.1 10.4.2 says at least 1 ms. */
+		mdelay(1);
+	}
+	/* phy wake/clear reset */
+	sata_scr_write_flush(ap, SCR_CONTROL, 0x300);
+
+	/* wait for phy to become ready, if necessary */
+	do {
+		msleep(200);
+		sata_scr_read(ap, SCR_STATUS, &sstatus);
+		if ((sstatus & 0xf) != 1)
+			break;
+	} while (time_before(jiffies, timeout));
+
+	/* print link status */
+	sata_print_link_status(ap);
+
+	/* TODO: phy layer with polling, timeouts, etc. */
+	if (!ata_port_offline(ap))
+		ata_port_probe(ap);
+	else
+		ata_port_disable(ap);
+
+	if (ap->flags & ATA_FLAG_DISABLED)
+		return;
+
+	if (ata_busy_sleep(ap, ATA_TMOUT_BOOT_QUICK, ATA_TMOUT_BOOT)) {
+		ata_port_disable(ap);
+		return;
+	}
+
+	ap->cbl = ATA_CBL_SATA;
+}
+
+/**
+ *	sata_phy_reset - Reset SATA bus.
+ *	@ap: SATA port associated with target SATA PHY.
+ *
+ *	This function resets the SATA bus, and then probes
+ *	the bus for devices.
+ *
+ *	LOCKING:
+ *	PCI/etc. bus probe sem.
+ *
+ */
+void sata_phy_reset(struct ata_port *ap)
+{
+	__sata_phy_reset(ap);
+	if (ap->flags & ATA_FLAG_DISABLED)
+		return;
+	ata_bus_reset(ap);
+}
+
+/**
+ *	ata_dev_pair		-	return other device on cable
+ *	@adev: device
+ *
+ *	Obtain the other device on the same cable, or if none is
+ *	present NULL is returned
+ */
+
+struct ata_device *ata_dev_pair(struct ata_device *adev)
+{
+	struct ata_port *ap = adev->ap;
+	struct ata_device *pair = &ap->device[1 - adev->devno];
+	if (!ata_dev_enabled(pair))
+		return NULL;
+	return pair;
+}
+
+/**
+ *	ata_port_disable - Disable port.
+ *	@ap: Port to be disabled.
+ *
+ *	Modify @ap data structure such that the system
+ *	thinks that the entire port is disabled, and should
+ *	never attempt to probe or communicate with devices
+ *	on this port.
+ *
+ *	LOCKING: host_set lock, or some other form of
+ *	serialization.
+ */
+
+void ata_port_disable(struct ata_port *ap)
+{
+	ap->device[0].class = ATA_DEV_NONE;
+	ap->device[1].class = ATA_DEV_NONE;
+	ap->flags |= ATA_FLAG_DISABLED;
+}
+
+/**
+ *	sata_down_spd_limit - adjust SATA spd limit downward
+ *	@ap: Port to adjust SATA spd limit for
+ *
+ *	Adjust SATA spd limit of @ap downward.  Note that this
+ *	function only adjusts the limit.  The change must be applied
+ *	using sata_set_spd().
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ *
+ *	RETURNS:
+ *	0 on success, negative errno on failure
+ */
+int sata_down_spd_limit(struct ata_port *ap)
+{
+	u32 sstatus, spd, mask;
+	int rc, highbit;
+
+	rc = sata_scr_read(ap, SCR_STATUS, &sstatus);
+	if (rc)
+		return rc;
+
+	mask = ap->sata_spd_limit;
+	if (mask <= 1)
+		return -EINVAL;
+	highbit = fls(mask) - 1;
+	mask &= ~(1 << highbit);
+
+	spd = (sstatus >> 4) & 0xf;
+	if (spd <= 1)
+		return -EINVAL;
+	spd--;
+	mask &= (1 << spd) - 1;
+	if (!mask)
+		return -EINVAL;
+
+	ap->sata_spd_limit = mask;
+
+	ata_port_printk(ap, KERN_WARNING, "limiting SATA link speed to %s\n",
+			sata_spd_string(fls(mask)));
+
+	return 0;
+}
+
+static int __sata_set_spd_needed(struct ata_port *ap, u32 *scontrol)
+{
+	u32 spd, limit;
+
+	if (ap->sata_spd_limit == UINT_MAX)
+		limit = 0;
+	else
+		limit = fls(ap->sata_spd_limit);
+
+	spd = (*scontrol >> 4) & 0xf;
+	*scontrol = (*scontrol & ~0xf0) | ((limit & 0xf) << 4);
+
+	return spd != limit;
+}
+
+/**
+ *	sata_set_spd_needed - is SATA spd configuration needed
+ *	@ap: Port in question
+ *
+ *	Test whether the spd limit in SControl matches
+ *	@ap->sata_spd_limit.  This function is used to determine
+ *	whether hardreset is necessary to apply SATA spd
+ *	configuration.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ *
+ *	RETURNS:
+ *	1 if SATA spd configuration is needed, 0 otherwise.
+ */
+int sata_set_spd_needed(struct ata_port *ap)
+{
+	u32 scontrol;
+
+	if (sata_scr_read(ap, SCR_CONTROL, &scontrol))
+		return 0;
+
+	return __sata_set_spd_needed(ap, &scontrol);
+}
+
+/**
+ *	sata_set_spd - set SATA spd according to spd limit
+ *	@ap: Port to set SATA spd for
+ *
+ *	Set SATA spd of @ap according to sata_spd_limit.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ *
+ *	RETURNS:
+ *	0 if spd doesn't need to be changed, 1 if spd has been
+ *	changed.  Negative errno if SCR registers are inaccessible.
+ */
+int sata_set_spd(struct ata_port *ap)
+{
+	u32 scontrol;
+	int rc;
+
+	if ((rc = sata_scr_read(ap, SCR_CONTROL, &scontrol)))
+		return rc;
+
+	if (!__sata_set_spd_needed(ap, &scontrol))
+		return 0;
+
+	if ((rc = sata_scr_write(ap, SCR_CONTROL, scontrol)))
+		return rc;
+
+	return 1;
+}
+
+/*
+ * This mode timing computation functionality is ported over from
+ * drivers/ide/ide-timing.h and was originally written by Vojtech Pavlik
+ */
+/*
+ * PIO 0-5, MWDMA 0-2 and UDMA 0-6 timings (in nanoseconds).
+ * These were taken from ATA/ATAPI-6 standard, rev 0a, except
+ * for PIO 5, which is a nonstandard extension and UDMA6, which
+ * is currently supported only by Maxtor drives.
+ */
+
+static const struct ata_timing ata_timing[] = {
+
+	{ XFER_UDMA_6,     0,   0,   0,   0,   0,   0,   0,  15 },
+	{ XFER_UDMA_5,     0,   0,   0,   0,   0,   0,   0,  20 },
+	{ XFER_UDMA_4,     0,   0,   0,   0,   0,   0,   0,  30 },
+	{ XFER_UDMA_3,     0,   0,   0,   0,   0,   0,   0,  45 },
+
+	{ XFER_UDMA_2,     0,   0,   0,   0,   0,   0,   0,  60 },
+	{ XFER_UDMA_1,     0,   0,   0,   0,   0,   0,   0,  80 },
+	{ XFER_UDMA_0,     0,   0,   0,   0,   0,   0,   0, 120 },
+
+/*	{ XFER_UDMA_SLOW,  0,   0,   0,   0,   0,   0,   0, 150 }, */
+
+	{ XFER_MW_DMA_2,  25,   0,   0,   0,  70,  25, 120,   0 },
+	{ XFER_MW_DMA_1,  45,   0,   0,   0,  80,  50, 150,   0 },
+	{ XFER_MW_DMA_0,  60,   0,   0,   0, 215, 215, 480,   0 },
+
+	{ XFER_SW_DMA_2,  60,   0,   0,   0, 120, 120, 240,   0 },
+	{ XFER_SW_DMA_1,  90,   0,   0,   0, 240, 240, 480,   0 },
+	{ XFER_SW_DMA_0, 120,   0,   0,   0, 480, 480, 960,   0 },
+
+/*	{ XFER_PIO_5,     20,  50,  30, 100,  50,  30, 100,   0 }, */
+	{ XFER_PIO_4,     25,  70,  25, 120,  70,  25, 120,   0 },
+	{ XFER_PIO_3,     30,  80,  70, 180,  80,  70, 180,   0 },
+
+	{ XFER_PIO_2,     30, 290,  40, 330, 100,  90, 240,   0 },
+	{ XFER_PIO_1,     50, 290,  93, 383, 125, 100, 383,   0 },
+	{ XFER_PIO_0,     70, 290, 240, 600, 165, 150, 600,   0 },
+
+/*	{ XFER_PIO_SLOW, 120, 290, 240, 960, 290, 240, 960,   0 }, */
+
+	{ 0xFF }
+};
+
+#define ENOUGH(v,unit)		(((v)-1)/(unit)+1)
+#define EZ(v,unit)		((v)?ENOUGH(v,unit):0)
+
+static void ata_timing_quantize(const struct ata_timing *t, struct ata_timing *q, int T, int UT)
+{
+	q->setup   = EZ(t->setup   * 1000,  T);
+	q->act8b   = EZ(t->act8b   * 1000,  T);
+	q->rec8b   = EZ(t->rec8b   * 1000,  T);
+	q->cyc8b   = EZ(t->cyc8b   * 1000,  T);
+	q->active  = EZ(t->active  * 1000,  T);
+	q->recover = EZ(t->recover * 1000,  T);
+	q->cycle   = EZ(t->cycle   * 1000,  T);
+	q->udma    = EZ(t->udma    * 1000, UT);
+}
+
+void ata_timing_merge(const struct ata_timing *a, const struct ata_timing *b,
+		      struct ata_timing *m, unsigned int what)
+{
+	if (what & ATA_TIMING_SETUP  ) m->setup   = max(a->setup,   b->setup);
+	if (what & ATA_TIMING_ACT8B  ) m->act8b   = max(a->act8b,   b->act8b);
+	if (what & ATA_TIMING_REC8B  ) m->rec8b   = max(a->rec8b,   b->rec8b);
+	if (what & ATA_TIMING_CYC8B  ) m->cyc8b   = max(a->cyc8b,   b->cyc8b);
+	if (what & ATA_TIMING_ACTIVE ) m->active  = max(a->active,  b->active);
+	if (what & ATA_TIMING_RECOVER) m->recover = max(a->recover, b->recover);
+	if (what & ATA_TIMING_CYCLE  ) m->cycle   = max(a->cycle,   b->cycle);
+	if (what & ATA_TIMING_UDMA   ) m->udma    = max(a->udma,    b->udma);
+}
+
+static const struct ata_timing* ata_timing_find_mode(unsigned short speed)
+{
+	const struct ata_timing *t;
+
+	for (t = ata_timing; t->mode != speed; t++)
+		if (t->mode == 0xFF)
+			return NULL;
+	return t;
+}
+
+int ata_timing_compute(struct ata_device *adev, unsigned short speed,
+		       struct ata_timing *t, int T, int UT)
+{
+	const struct ata_timing *s;
+	struct ata_timing p;
+
+	/*
+	 * Find the mode.
+	 */
+
+	if (!(s = ata_timing_find_mode(speed)))
+		return -EINVAL;
+
+	memcpy(t, s, sizeof(*s));
+
+	/*
+	 * If the drive is an EIDE drive, it can tell us it needs extended
+	 * PIO/MW_DMA cycle timing.
+	 */
+
+	if (adev->id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE drive */
+		memset(&p, 0, sizeof(p));
+		if(speed >= XFER_PIO_0 && speed <= XFER_SW_DMA_0) {
+			if (speed <= XFER_PIO_2) p.cycle = p.cyc8b = adev->id[ATA_ID_EIDE_PIO];
+					    else p.cycle = p.cyc8b = adev->id[ATA_ID_EIDE_PIO_IORDY];
+		} else if(speed >= XFER_MW_DMA_0 && speed <= XFER_MW_DMA_2) {
+			p.cycle = adev->id[ATA_ID_EIDE_DMA_MIN];
+		}
+		ata_timing_merge(&p, t, t, ATA_TIMING_CYCLE | ATA_TIMING_CYC8B);
+	}
+
+	/*
+	 * Convert the timing to bus clock counts.
+	 */
+
+	ata_timing_quantize(t, t, T, UT);
+
+	/*
+	 * Even in DMA/UDMA modes we still use PIO access for IDENTIFY,
+	 * S.M.A.R.T * and some other commands. We have to ensure that the
+	 * DMA cycle timing is slower/equal than the fastest PIO timing.
+	 */
+
+	if (speed > XFER_PIO_4) {
+		ata_timing_compute(adev, adev->pio_mode, &p, T, UT);
+		ata_timing_merge(&p, t, t, ATA_TIMING_ALL);
+	}
+
+	/*
+	 * Lengthen active & recovery time so that cycle time is correct.
+	 */
+
+	if (t->act8b + t->rec8b < t->cyc8b) {
+		t->act8b += (t->cyc8b - (t->act8b + t->rec8b)) / 2;
+		t->rec8b = t->cyc8b - t->act8b;
+	}
+
+	if (t->active + t->recover < t->cycle) {
+		t->active += (t->cycle - (t->active + t->recover)) / 2;
+		t->recover = t->cycle - t->active;
+	}
+
+	return 0;
+}
+
+/**
+ *	ata_down_xfermask_limit - adjust dev xfer masks downward
+ *	@dev: Device to adjust xfer masks
+ *	@force_pio0: Force PIO0
+ *
+ *	Adjust xfer masks of @dev downward.  Note that this function
+ *	does not apply the change.  Invoking ata_set_mode() afterwards
+ *	will apply the limit.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ *
+ *	RETURNS:
+ *	0 on success, negative errno on failure
+ */
+int ata_down_xfermask_limit(struct ata_device *dev, int force_pio0)
+{
+	unsigned long xfer_mask;
+	int highbit;
+
+	xfer_mask = ata_pack_xfermask(dev->pio_mask, dev->mwdma_mask,
+				      dev->udma_mask);
+
+	if (!xfer_mask)
+		goto fail;
+	/* don't gear down to MWDMA from UDMA, go directly to PIO */
+	if (xfer_mask & ATA_MASK_UDMA)
+		xfer_mask &= ~ATA_MASK_MWDMA;
+
+	highbit = fls(xfer_mask) - 1;
+	xfer_mask &= ~(1 << highbit);
+	if (force_pio0)
+		xfer_mask &= 1 << ATA_SHIFT_PIO;
+	if (!xfer_mask)
+		goto fail;
+
+	ata_unpack_xfermask(xfer_mask, &dev->pio_mask, &dev->mwdma_mask,
+			    &dev->udma_mask);
+
+	ata_dev_printk(dev, KERN_WARNING, "limiting speed to %s\n",
+		       ata_mode_string(xfer_mask));
+
+	return 0;
+
+ fail:
+	return -EINVAL;
+}
+
+static int ata_dev_set_mode(struct ata_device *dev)
+{
+	unsigned int err_mask;
+	int rc;
+
+	dev->flags &= ~ATA_DFLAG_PIO;
+	if (dev->xfer_shift == ATA_SHIFT_PIO)
+		dev->flags |= ATA_DFLAG_PIO;
+
+	err_mask = ata_dev_set_xfermode(dev);
+	if (err_mask) {
+		ata_dev_printk(dev, KERN_ERR, "failed to set xfermode "
+			       "(err_mask=0x%x)\n", err_mask);
+		return -EIO;
+	}
+
+	rc = ata_dev_revalidate(dev, 0);
+	if (rc)
+		return rc;
+
+	DPRINTK("xfer_shift=%u, xfer_mode=0x%x\n",
+		dev->xfer_shift, (int)dev->xfer_mode);
+
+	ata_dev_printk(dev, KERN_INFO, "configured for %s\n",
+		       ata_mode_string(ata_xfer_mode2mask(dev->xfer_mode)));
+	return 0;
+}
+
+/**
+ *	ata_set_mode - Program timings and issue SET FEATURES - XFER
+ *	@ap: port on which timings will be programmed
+ *	@r_failed_dev: out paramter for failed device
+ *
+ *	Set ATA device disk transfer mode (PIO3, UDMA6, etc.).  If
+ *	ata_set_mode() fails, pointer to the failing device is
+ *	returned in @r_failed_dev.
+ *
+ *	LOCKING:
+ *	PCI/etc. bus probe sem.
+ *
+ *	RETURNS:
+ *	0 on success, negative errno otherwise
+ */
+int ata_set_mode(struct ata_port *ap, struct ata_device **r_failed_dev)
+{
+	struct ata_device *dev;
+	int i, rc = 0, used_dma = 0, found = 0;
+
+	/* has private set_mode? */
+	if (ap->ops->set_mode) {
+		/* FIXME: make ->set_mode handle no device case and
+		 * return error code and failing device on failure.
+		 */
+		for (i = 0; i < ATA_MAX_DEVICES; i++) {
+			if (ata_dev_ready(&ap->device[i])) {
+				ap->ops->set_mode(ap);
+				break;
+			}
+		}
+		return 0;
+	}
+
+	/* step 1: calculate xfer_mask */
+	for (i = 0; i < ATA_MAX_DEVICES; i++) {
+		unsigned int pio_mask, dma_mask;
+
+		dev = &ap->device[i];
+
+		if (!ata_dev_enabled(dev))
+			continue;
+
+		ata_dev_xfermask(dev);
+
+		pio_mask = ata_pack_xfermask(dev->pio_mask, 0, 0);
+		dma_mask = ata_pack_xfermask(0, dev->mwdma_mask, dev->udma_mask);
+		dev->pio_mode = ata_xfer_mask2mode(pio_mask);
+		dev->dma_mode = ata_xfer_mask2mode(dma_mask);
+
+		found = 1;
+		if (dev->dma_mode)
+			used_dma = 1;
+	}
+	if (!found)
+		goto out;
+
+	/* step 2: always set host PIO timings */
+	for (i = 0; i < ATA_MAX_DEVICES; i++) {
+		dev = &ap->device[i];
+		if (!ata_dev_enabled(dev))
+			continue;
+
+		if (!dev->pio_mode) {
+			ata_dev_printk(dev, KERN_WARNING, "no PIO support\n");
+			rc = -EINVAL;
+			goto out;
+		}
+
+		dev->xfer_mode = dev->pio_mode;
+		dev->xfer_shift = ATA_SHIFT_PIO;
+		if (ap->ops->set_piomode)
+			ap->ops->set_piomode(ap, dev);
+	}
+
+	/* step 3: set host DMA timings */
+	for (i = 0; i < ATA_MAX_DEVICES; i++) {
+		dev = &ap->device[i];
+
+		if (!ata_dev_enabled(dev) || !dev->dma_mode)
+			continue;
+
+		dev->xfer_mode = dev->dma_mode;
+		dev->xfer_shift = ata_xfer_mode2shift(dev->dma_mode);
+		if (ap->ops->set_dmamode)
+			ap->ops->set_dmamode(ap, dev);
+	}
+
+	/* step 4: update devices' xfer mode */
+	for (i = 0; i < ATA_MAX_DEVICES; i++) {
+		dev = &ap->device[i];
+
+		/* don't udpate suspended devices' xfer mode */
+		if (!ata_dev_ready(dev))
+			continue;
+
+		rc = ata_dev_set_mode(dev);
+		if (rc)
+			goto out;
+	}
+
+	/* Record simplex status. If we selected DMA then the other
+	 * host channels are not permitted to do so.
+	 */
+	if (used_dma && (ap->host_set->flags & ATA_HOST_SIMPLEX))
+		ap->host_set->simplex_claimed = 1;
+
+	/* step5: chip specific finalisation */
+	if (ap->ops->post_set_mode)
+		ap->ops->post_set_mode(ap);
+
+ out:
+	if (rc)
+		*r_failed_dev = dev;
+	return rc;
+}
+
+/**
+ *	ata_tf_to_host - issue ATA taskfile to host controller
+ *	@ap: port to which command is being issued
+ *	@tf: ATA taskfile register set
+ *
+ *	Issues ATA taskfile register set to ATA host controller,
+ *	with proper synchronization with interrupt handler and
+ *	other threads.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ */
+
+static inline void ata_tf_to_host(struct ata_port *ap,
+				  const struct ata_taskfile *tf)
+{
+	ap->ops->tf_load(ap, tf);
+	ap->ops->exec_command(ap, tf);
+}
+
+/**
+ *	ata_busy_sleep - sleep until BSY clears, or timeout
+ *	@ap: port containing status register to be polled
+ *	@tmout_pat: impatience timeout
+ *	@tmout: overall timeout
+ *
+ *	Sleep until ATA Status register bit BSY clears,
+ *	or a timeout occurs.
+ *
+ *	LOCKING: None.
+ */
+
+unsigned int ata_busy_sleep (struct ata_port *ap,
+			     unsigned long tmout_pat, unsigned long tmout)
+{
+	unsigned long timer_start, timeout;
+	u8 status;
+
+	status = ata_busy_wait(ap, ATA_BUSY, 300);
+	timer_start = jiffies;
+	timeout = timer_start + tmout_pat;
+	while ((status & ATA_BUSY) && (time_before(jiffies, timeout))) {
+		msleep(50);
+		status = ata_busy_wait(ap, ATA_BUSY, 3);
+	}
+
+	if (status & ATA_BUSY)
+		ata_port_printk(ap, KERN_WARNING,
+				"port is slow to respond, please be patient\n");
+
+	timeout = timer_start + tmout;
+	while ((status & ATA_BUSY) && (time_before(jiffies, timeout))) {
+		msleep(50);
+		status = ata_chk_status(ap);
+	}
+
+	if (status & ATA_BUSY) {
+		ata_port_printk(ap, KERN_ERR, "port failed to respond "
+				"(%lu secs)\n", tmout / HZ);
+		return 1;
+	}
+
+	return 0;
+}
+
+static void ata_bus_post_reset(struct ata_port *ap, unsigned int devmask)
+{
+	struct ata_ioports *ioaddr = &ap->ioaddr;
+	unsigned int dev0 = devmask & (1 << 0);
+	unsigned int dev1 = devmask & (1 << 1);
+	unsigned long timeout;
+
+	/* if device 0 was found in ata_devchk, wait for its
+	 * BSY bit to clear
+	 */
+	if (dev0)
+		ata_busy_sleep(ap, ATA_TMOUT_BOOT_QUICK, ATA_TMOUT_BOOT);
+
+	/* if device 1 was found in ata_devchk, wait for
+	 * register access, then wait for BSY to clear
+	 */
+	timeout = jiffies + ATA_TMOUT_BOOT;
+	while (dev1) {
+		u8 nsect, lbal;
+
+		ap->ops->dev_select(ap, 1);
+		if (ap->flags & ATA_FLAG_MMIO) {
+			nsect = readb((void __iomem *) ioaddr->nsect_addr);
+			lbal = readb((void __iomem *) ioaddr->lbal_addr);
+		} else {
+			nsect = inb(ioaddr->nsect_addr);
+			lbal = inb(ioaddr->lbal_addr);
+		}
+		if ((nsect == 1) && (lbal == 1))
+			break;
+		if (time_after(jiffies, timeout)) {
+			dev1 = 0;
+			break;
+		}
+		msleep(50);	/* give drive a breather */
+	}
+	if (dev1)
+		ata_busy_sleep(ap, ATA_TMOUT_BOOT_QUICK, ATA_TMOUT_BOOT);
+
+	/* is all this really necessary? */
+	ap->ops->dev_select(ap, 0);
+	if (dev1)
+		ap->ops->dev_select(ap, 1);
+	if (dev0)
+		ap->ops->dev_select(ap, 0);
+}
+
+static unsigned int ata_bus_softreset(struct ata_port *ap,
+				      unsigned int devmask)
+{
+	struct ata_ioports *ioaddr = &ap->ioaddr;
+
+	DPRINTK("ata%u: bus reset via SRST\n", ap->id);
+
+	/* software reset.  causes dev0 to be selected */
+	if (ap->flags & ATA_FLAG_MMIO) {
+		writeb(ap->ctl, (void __iomem *) ioaddr->ctl_addr);
+		udelay(20);	/* FIXME: flush */
+		writeb(ap->ctl | ATA_SRST, (void __iomem *) ioaddr->ctl_addr);
+		udelay(20);	/* FIXME: flush */
+		writeb(ap->ctl, (void __iomem *) ioaddr->ctl_addr);
+	} else {
+		outb(ap->ctl, ioaddr->ctl_addr);
+		udelay(10);
+		outb(ap->ctl | ATA_SRST, ioaddr->ctl_addr);
+		udelay(10);
+		outb(ap->ctl, ioaddr->ctl_addr);
+	}
+
+	/* spec mandates ">= 2ms" before checking status.
+	 * We wait 150ms, because that was the magic delay used for
+	 * ATAPI devices in Hale Landis's ATADRVR, for the period of time
+	 * between when the ATA command register is written, and then
+	 * status is checked.  Because waiting for "a while" before
+	 * checking status is fine, post SRST, we perform this magic
+	 * delay here as well.
+	 *
+	 * Old drivers/ide uses the 2mS rule and then waits for ready
+	 */
+	msleep(150);
+
+	/* Before we perform post reset processing we want to see if
+	 * the bus shows 0xFF because the odd clown forgets the D7
+	 * pulldown resistor.
+	 */
+	if (ata_check_status(ap) == 0xFF) {
+		ata_port_printk(ap, KERN_ERR, "SRST failed (status 0xFF)\n");
+		return AC_ERR_OTHER;
+	}
+
+	ata_bus_post_reset(ap, devmask);
+
+	return 0;
+}
+
+/**
+ *	ata_bus_reset - reset host port and associated ATA channel
+ *	@ap: port to reset
+ *
+ *	This is typically the first time we actually start issuing
+ *	commands to the ATA channel.  We wait for BSY to clear, then
+ *	issue EXECUTE DEVICE DIAGNOSTIC command, polling for its
+ *	result.  Determine what devices, if any, are on the channel
+ *	by looking at the device 0/1 error register.  Look at the signature
+ *	stored in each device's taskfile registers, to determine if
+ *	the device is ATA or ATAPI.
+ *
+ *	LOCKING:
+ *	PCI/etc. bus probe sem.
+ *	Obtains host_set lock.
+ *
+ *	SIDE EFFECTS:
+ *	Sets ATA_FLAG_DISABLED if bus reset fails.
+ */
+
+void ata_bus_reset(struct ata_port *ap)
+{
+	struct ata_ioports *ioaddr = &ap->ioaddr;
+	unsigned int slave_possible = ap->flags & ATA_FLAG_SLAVE_POSS;
+	u8 err;
+	unsigned int dev0, dev1 = 0, devmask = 0;
+
+	DPRINTK("ENTER, host %u, port %u\n", ap->id, ap->port_no);
+
+	/* determine if device 0/1 are present */
+	if (ap->flags & ATA_FLAG_SATA_RESET)
+		dev0 = 1;
+	else {
+		dev0 = ata_devchk(ap, 0);
+		if (slave_possible)
+			dev1 = ata_devchk(ap, 1);
+	}
+
+	if (dev0)
+		devmask |= (1 << 0);
+	if (dev1)
+		devmask |= (1 << 1);
+
+	/* select device 0 again */
+	ap->ops->dev_select(ap, 0);
+
+	/* issue bus reset */
+	if (ap->flags & ATA_FLAG_SRST)
+		if (ata_bus_softreset(ap, devmask))
+			goto err_out;
+
+	/*
+	 * determine by signature whether we have ATA or ATAPI devices
+	 */
+	ap->device[0].class = ata_dev_try_classify(ap, 0, &err);
+	if ((slave_possible) && (err != 0x81))
+		ap->device[1].class = ata_dev_try_classify(ap, 1, &err);
+
+	/* re-enable interrupts */
+	if (ap->ioaddr.ctl_addr)	/* FIXME: hack. create a hook instead */
+		ata_irq_on(ap);
+
+	/* is double-select really necessary? */
+	if (ap->device[1].class != ATA_DEV_NONE)
+		ap->ops->dev_select(ap, 1);
+	if (ap->device[0].class != ATA_DEV_NONE)
+		ap->ops->dev_select(ap, 0);
+
+	/* if no devices were detected, disable this port */
+	if ((ap->device[0].class == ATA_DEV_NONE) &&
+	    (ap->device[1].class == ATA_DEV_NONE))
+		goto err_out;
+
+	if (ap->flags & (ATA_FLAG_SATA_RESET | ATA_FLAG_SRST)) {
+		/* set up device control for ATA_FLAG_SATA_RESET */
+		if (ap->flags & ATA_FLAG_MMIO)
+			writeb(ap->ctl, (void __iomem *) ioaddr->ctl_addr);
+		else
+			outb(ap->ctl, ioaddr->ctl_addr);
+	}
+
+	DPRINTK("EXIT\n");
+	return;
+
+err_out:
+	ata_port_printk(ap, KERN_ERR, "disabling port\n");
+	ap->ops->port_disable(ap);
+
+	DPRINTK("EXIT\n");
+}
+
+/**
+ *	sata_phy_debounce - debounce SATA phy status
+ *	@ap: ATA port to debounce SATA phy status for
+ *	@params: timing parameters { interval, duratinon, timeout } in msec
+ *
+ *	Make sure SStatus of @ap reaches stable state, determined by
+ *	holding the same value where DET is not 1 for @duration polled
+ *	every @interval, before @timeout.  Timeout constraints the
+ *	beginning of the stable state.  Because, after hot unplugging,
+ *	DET gets stuck at 1 on some controllers, this functions waits
+ *	until timeout then returns 0 if DET is stable at 1.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep)
+ *
+ *	RETURNS:
+ *	0 on success, -errno on failure.
+ */
+int sata_phy_debounce(struct ata_port *ap, const unsigned long *params)
+{
+	unsigned long interval_msec = params[0];
+	unsigned long duration = params[1] * HZ / 1000;
+	unsigned long timeout = jiffies + params[2] * HZ / 1000;
+	unsigned long last_jiffies;
+	u32 last, cur;
+	int rc;
+
+	if ((rc = sata_scr_read(ap, SCR_STATUS, &cur)))
+		return rc;
+	cur &= 0xf;
+
+	last = cur;
+	last_jiffies = jiffies;
+
+	while (1) {
+		msleep(interval_msec);
+		if ((rc = sata_scr_read(ap, SCR_STATUS, &cur)))
+			return rc;
+		cur &= 0xf;
+
+		/* DET stable? */
+		if (cur == last) {
+			if (cur == 1 && time_before(jiffies, timeout))
+				continue;
+			if (time_after(jiffies, last_jiffies + duration))
+				return 0;
+			continue;
+		}
+
+		/* unstable, start over */
+		last = cur;
+		last_jiffies = jiffies;
+
+		/* check timeout */
+		if (time_after(jiffies, timeout))
+			return -EBUSY;
+	}
+}
+
+/**
+ *	sata_phy_resume - resume SATA phy
+ *	@ap: ATA port to resume SATA phy for
+ *	@params: timing parameters { interval, duratinon, timeout } in msec
+ *
+ *	Resume SATA phy of @ap and debounce it.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep)
+ *
+ *	RETURNS:
+ *	0 on success, -errno on failure.
+ */
+int sata_phy_resume(struct ata_port *ap, const unsigned long *params)
+{
+	u32 scontrol;
+	int rc;
+
+	if ((rc = sata_scr_read(ap, SCR_CONTROL, &scontrol)))
+		return rc;
+
+	scontrol = (scontrol & 0x0f0) | 0x300;
+
+	if ((rc = sata_scr_write(ap, SCR_CONTROL, scontrol)))
+		return rc;
+
+	/* Some PHYs react badly if SStatus is pounded immediately
+	 * after resuming.  Delay 200ms before debouncing.
+	 */
+	msleep(200);
+
+	return sata_phy_debounce(ap, params);
+}
+
+static void ata_wait_spinup(struct ata_port *ap)
+{
+	struct ata_eh_context *ehc = &ap->eh_context;
+	unsigned long end, secs;
+	int rc;
+
+	/* first, debounce phy if SATA */
+	if (ap->cbl == ATA_CBL_SATA) {
+		rc = sata_phy_debounce(ap, sata_deb_timing_hotplug);
+
+		/* if debounced successfully and offline, no need to wait */
+		if ((rc == 0 || rc == -EOPNOTSUPP) && ata_port_offline(ap))
+			return;
+	}
+
+	/* okay, let's give the drive time to spin up */
+	end = ehc->i.hotplug_timestamp + ATA_SPINUP_WAIT * HZ / 1000;
+	secs = ((end - jiffies) + HZ - 1) / HZ;
+
+	if (time_after(jiffies, end))
+		return;
+
+	if (secs > 5)
+		ata_port_printk(ap, KERN_INFO, "waiting for device to spin up "
+				"(%lu secs)\n", secs);
+
+	schedule_timeout_uninterruptible(end - jiffies);
+}
+
+/**
+ *	ata_std_prereset - prepare for reset
+ *	@ap: ATA port to be reset
+ *
+ *	@ap is about to be reset.  Initialize it.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep)
+ *
+ *	RETURNS:
+ *	0 on success, -errno otherwise.
+ */
+int ata_std_prereset(struct ata_port *ap)
+{
+	struct ata_eh_context *ehc = &ap->eh_context;
+	const unsigned long *timing = sata_ehc_deb_timing(ehc);
+	int rc;
+
+	/* handle link resume & hotplug spinup */
+	if ((ehc->i.flags & ATA_EHI_RESUME_LINK) &&
+	    (ap->flags & ATA_FLAG_HRST_TO_RESUME))
+		ehc->i.action |= ATA_EH_HARDRESET;
+
+	if ((ehc->i.flags & ATA_EHI_HOTPLUGGED) &&
+	    (ap->flags & ATA_FLAG_SKIP_D2H_BSY))
+		ata_wait_spinup(ap);
+
+	/* if we're about to do hardreset, nothing more to do */
+	if (ehc->i.action & ATA_EH_HARDRESET)
+		return 0;
+
+	/* if SATA, resume phy */
+	if (ap->cbl == ATA_CBL_SATA) {
+		rc = sata_phy_resume(ap, timing);
+		if (rc && rc != -EOPNOTSUPP) {
+			/* phy resume failed */
+			ata_port_printk(ap, KERN_WARNING, "failed to resume "
+					"link for reset (errno=%d)\n", rc);
+			return rc;
+		}
+	}
+
+	/* Wait for !BSY if the controller can wait for the first D2H
+	 * Reg FIS and we don't know that no device is attached.
+	 */
+	if (!(ap->flags & ATA_FLAG_SKIP_D2H_BSY) && !ata_port_offline(ap))
+		ata_busy_sleep(ap, ATA_TMOUT_BOOT_QUICK, ATA_TMOUT_BOOT);
+
+	return 0;
+}
+
+/**
+ *	ata_std_softreset - reset host port via ATA SRST
+ *	@ap: port to reset
+ *	@classes: resulting classes of attached devices
+ *
+ *	Reset host port using ATA SRST.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep)
+ *
+ *	RETURNS:
+ *	0 on success, -errno otherwise.
+ */
+int ata_std_softreset(struct ata_port *ap, unsigned int *classes)
+{
+	unsigned int slave_possible = ap->flags & ATA_FLAG_SLAVE_POSS;
+	unsigned int devmask = 0, err_mask;
+	u8 err;
+
+	DPRINTK("ENTER\n");
+
+	if (ata_port_offline(ap)) {
+		classes[0] = ATA_DEV_NONE;
+		goto out;
+	}
+
+	/* determine if device 0/1 are present */
+	if (ata_devchk(ap, 0))
+		devmask |= (1 << 0);
+	if (slave_possible && ata_devchk(ap, 1))
+		devmask |= (1 << 1);
+
+	/* select device 0 again */
+	ap->ops->dev_select(ap, 0);
+
+	/* issue bus reset */
+	DPRINTK("about to softreset, devmask=%x\n", devmask);
+	err_mask = ata_bus_softreset(ap, devmask);
+	if (err_mask) {
+		ata_port_printk(ap, KERN_ERR, "SRST failed (err_mask=0x%x)\n",
+				err_mask);
+		return -EIO;
+	}
+
+	/* determine by signature whether we have ATA or ATAPI devices */
+	classes[0] = ata_dev_try_classify(ap, 0, &err);
+	if (slave_possible && err != 0x81)
+		classes[1] = ata_dev_try_classify(ap, 1, &err);
+
+ out:
+	DPRINTK("EXIT, classes[0]=%u [1]=%u\n", classes[0], classes[1]);
+	return 0;
+}
+
+/**
+ *	sata_std_hardreset - reset host port via SATA phy reset
+ *	@ap: port to reset
+ *	@class: resulting class of attached device
+ *
+ *	SATA phy-reset host port using DET bits of SControl register.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep)
+ *
+ *	RETURNS:
+ *	0 on success, -errno otherwise.
+ */
+int sata_std_hardreset(struct ata_port *ap, unsigned int *class)
+{
+	struct ata_eh_context *ehc = &ap->eh_context;
+	const unsigned long *timing = sata_ehc_deb_timing(ehc);
+	u32 scontrol;
+	int rc;
+
+	DPRINTK("ENTER\n");
+
+	if (sata_set_spd_needed(ap)) {
+		/* SATA spec says nothing about how to reconfigure
+		 * spd.  To be on the safe side, turn off phy during
+		 * reconfiguration.  This works for at least ICH7 AHCI
+		 * and Sil3124.
+		 */
+		if ((rc = sata_scr_read(ap, SCR_CONTROL, &scontrol)))
+			return rc;
+
+		scontrol = (scontrol & 0x0f0) | 0x302;
+
+		if ((rc = sata_scr_write(ap, SCR_CONTROL, scontrol)))
+			return rc;
+
+		sata_set_spd(ap);
+	}
+
+	/* issue phy wake/reset */
+	if ((rc = sata_scr_read(ap, SCR_CONTROL, &scontrol)))
+		return rc;
+
+	scontrol = (scontrol & 0x0f0) | 0x301;
+
+	if ((rc = sata_scr_write_flush(ap, SCR_CONTROL, scontrol)))
+		return rc;
+
+	/* Couldn't find anything in SATA I/II specs, but AHCI-1.1
+	 * 10.4.2 says at least 1 ms.
+	 */
+	msleep(1);
+
+	/* bring phy back */
+	sata_phy_resume(ap, timing);
+
+	/* TODO: phy layer with polling, timeouts, etc. */
+	if (ata_port_offline(ap)) {
+		*class = ATA_DEV_NONE;
+		DPRINTK("EXIT, link offline\n");
+		return 0;
+	}
+
+	if (ata_busy_sleep(ap, ATA_TMOUT_BOOT_QUICK, ATA_TMOUT_BOOT)) {
+		ata_port_printk(ap, KERN_ERR,
+				"COMRESET failed (device not ready)\n");
+		return -EIO;
+	}
+
+	ap->ops->dev_select(ap, 0);	/* probably unnecessary */
+
+	*class = ata_dev_try_classify(ap, 0, NULL);
+
+	DPRINTK("EXIT, class=%u\n", *class);
+	return 0;
+}
+
+/**
+ *	ata_std_postreset - standard postreset callback
+ *	@ap: the target ata_port
+ *	@classes: classes of attached devices
+ *
+ *	This function is invoked after a successful reset.  Note that
+ *	the device might have been reset more than once using
+ *	different reset methods before postreset is invoked.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep)
+ */
+void ata_std_postreset(struct ata_port *ap, unsigned int *classes)
+{
+	u32 serror;
+
+	DPRINTK("ENTER\n");
+
+	/* print link status */
+	sata_print_link_status(ap);
+
+	/* clear SError */
+	if (sata_scr_read(ap, SCR_ERROR, &serror) == 0)
+		sata_scr_write(ap, SCR_ERROR, serror);
+
+	/* re-enable interrupts */
+	if (!ap->ops->error_handler) {
+		/* FIXME: hack. create a hook instead */
+		if (ap->ioaddr.ctl_addr)
+			ata_irq_on(ap);
+	}
+
+	/* is double-select really necessary? */
+	if (classes[0] != ATA_DEV_NONE)
+		ap->ops->dev_select(ap, 1);
+	if (classes[1] != ATA_DEV_NONE)
+		ap->ops->dev_select(ap, 0);
+
+	/* bail out if no device is present */
+	if (classes[0] == ATA_DEV_NONE && classes[1] == ATA_DEV_NONE) {
+		DPRINTK("EXIT, no device\n");
+		return;
+	}
+
+	/* set up device control */
+	if (ap->ioaddr.ctl_addr) {
+		if (ap->flags & ATA_FLAG_MMIO)
+			writeb(ap->ctl, (void __iomem *) ap->ioaddr.ctl_addr);
+		else
+			outb(ap->ctl, ap->ioaddr.ctl_addr);
+	}
+
+	DPRINTK("EXIT\n");
+}
+
+/**
+ *	ata_dev_same_device - Determine whether new ID matches configured device
+ *	@dev: device to compare against
+ *	@new_class: class of the new device
+ *	@new_id: IDENTIFY page of the new device
+ *
+ *	Compare @new_class and @new_id against @dev and determine
+ *	whether @dev is the device indicated by @new_class and
+ *	@new_id.
+ *
+ *	LOCKING:
+ *	None.
+ *
+ *	RETURNS:
+ *	1 if @dev matches @new_class and @new_id, 0 otherwise.
+ */
+static int ata_dev_same_device(struct ata_device *dev, unsigned int new_class,
+			       const u16 *new_id)
+{
+	const u16 *old_id = dev->id;
+	unsigned char model[2][41], serial[2][21];
+	u64 new_n_sectors;
+
+	if (dev->class != new_class) {
+		ata_dev_printk(dev, KERN_INFO, "class mismatch %d != %d\n",
+			       dev->class, new_class);
+		return 0;
+	}
+
+	ata_id_c_string(old_id, model[0], ATA_ID_PROD_OFS, sizeof(model[0]));
+	ata_id_c_string(new_id, model[1], ATA_ID_PROD_OFS, sizeof(model[1]));
+	ata_id_c_string(old_id, serial[0], ATA_ID_SERNO_OFS, sizeof(serial[0]));
+	ata_id_c_string(new_id, serial[1], ATA_ID_SERNO_OFS, sizeof(serial[1]));
+	new_n_sectors = ata_id_n_sectors(new_id);
+
+	if (strcmp(model[0], model[1])) {
+		ata_dev_printk(dev, KERN_INFO, "model number mismatch "
+			       "'%s' != '%s'\n", model[0], model[1]);
+		return 0;
+	}
+
+	if (strcmp(serial[0], serial[1])) {
+		ata_dev_printk(dev, KERN_INFO, "serial number mismatch "
+			       "'%s' != '%s'\n", serial[0], serial[1]);
+		return 0;
+	}
+
+	if (dev->class == ATA_DEV_ATA && dev->n_sectors != new_n_sectors) {
+		ata_dev_printk(dev, KERN_INFO, "n_sectors mismatch "
+			       "%llu != %llu\n",
+			       (unsigned long long)dev->n_sectors,
+			       (unsigned long long)new_n_sectors);
+		return 0;
+	}
+
+	return 1;
+}
+
+/**
+ *	ata_dev_revalidate - Revalidate ATA device
+ *	@dev: device to revalidate
+ *	@post_reset: is this revalidation after reset?
+ *
+ *	Re-read IDENTIFY page and make sure @dev is still attached to
+ *	the port.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep)
+ *
+ *	RETURNS:
+ *	0 on success, negative errno otherwise
+ */
+int ata_dev_revalidate(struct ata_device *dev, int post_reset)
+{
+	unsigned int class = dev->class;
+	u16 *id = (void *)dev->ap->sector_buf;
+	int rc;
+
+	if (!ata_dev_enabled(dev)) {
+		rc = -ENODEV;
+		goto fail;
+	}
+
+	/* read ID data */
+	rc = ata_dev_read_id(dev, &class, post_reset, id);
+	if (rc)
+		goto fail;
+
+	/* is the device still there? */
+	if (!ata_dev_same_device(dev, class, id)) {
+		rc = -ENODEV;
+		goto fail;
+	}
+
+	memcpy(dev->id, id, sizeof(id[0]) * ATA_ID_WORDS);
+
+	/* configure device according to the new ID */
+	rc = ata_dev_configure(dev, 0);
+	if (rc == 0)
+		return 0;
+
+ fail:
+	ata_dev_printk(dev, KERN_ERR, "revalidation failed (errno=%d)\n", rc);
+	return rc;
+}
+
+static const char * const ata_dma_blacklist [] = {
+	"WDC AC11000H", NULL,
+	"WDC AC22100H", NULL,
+	"WDC AC32500H", NULL,
+	"WDC AC33100H", NULL,
+	"WDC AC31600H", NULL,
+	"WDC AC32100H", "24.09P07",
+	"WDC AC23200L", "21.10N21",
+	"Compaq CRD-8241B",  NULL,
+	"CRD-8400B", NULL,
+	"CRD-8480B", NULL,
+	"CRD-8482B", NULL,
+ 	"CRD-84", NULL,
+	"SanDisk SDP3B", NULL,
+	"SanDisk SDP3B-64", NULL,
+	"SANYO CD-ROM CRD", NULL,
+	"HITACHI CDR-8", NULL,
+	"HITACHI CDR-8335", NULL,
+	"HITACHI CDR-8435", NULL,
+	"Toshiba CD-ROM XM-6202B", NULL,
+	"TOSHIBA CD-ROM XM-1702BC", NULL,
+	"CD-532E-A", NULL,
+	"E-IDE CD-ROM CR-840", NULL,
+	"CD-ROM Drive/F5A", NULL,
+	"WPI CDD-820", NULL,
+	"SAMSUNG CD-ROM SC-148C", NULL,
+	"SAMSUNG CD-ROM SC", NULL,
+	"SanDisk SDP3B-64", NULL,
+	"ATAPI CD-ROM DRIVE 40X MAXIMUM",NULL,
+	"_NEC DV5800A", NULL,
+	"SAMSUNG CD-ROM SN-124", "N001"
+};
+
+static int ata_strim(char *s, size_t len)
+{
+	len = strnlen(s, len);
+
+	/* ATAPI specifies that empty space is blank-filled; remove blanks */
+	while ((len > 0) && (s[len - 1] == ' ')) {
+		len--;
+		s[len] = 0;
+	}
+	return len;
+}
+
+static int ata_dma_blacklisted(const struct ata_device *dev)
+{
+	unsigned char model_num[40];
+	unsigned char model_rev[16];
+	unsigned int nlen, rlen;
+	int i;
+
+	/* We don't support polling DMA.
+	 * DMA blacklist those ATAPI devices with CDB-intr (and use PIO)
+	 * if the LLDD handles only interrupts in the HSM_ST_LAST state.
+	 */
+	if ((dev->ap->flags & ATA_FLAG_PIO_POLLING) &&
+	    (dev->flags & ATA_DFLAG_CDB_INTR))
+		return 1;
+
+	ata_id_string(dev->id, model_num, ATA_ID_PROD_OFS,
+			  sizeof(model_num));
+	ata_id_string(dev->id, model_rev, ATA_ID_FW_REV_OFS,
+			  sizeof(model_rev));
+	nlen = ata_strim(model_num, sizeof(model_num));
+	rlen = ata_strim(model_rev, sizeof(model_rev));
+
+	for (i = 0; i < ARRAY_SIZE(ata_dma_blacklist); i += 2) {
+		if (!strncmp(ata_dma_blacklist[i], model_num, nlen)) {
+			if (ata_dma_blacklist[i+1] == NULL)
+				return 1;
+			if (!strncmp(ata_dma_blacklist[i], model_rev, rlen))
+				return 1;
+		}
+	}
+	return 0;
+}
+
+/**
+ *	ata_dev_xfermask - Compute supported xfermask of the given device
+ *	@dev: Device to compute xfermask for
+ *
+ *	Compute supported xfermask of @dev and store it in
+ *	dev->*_mask.  This function is responsible for applying all
+ *	known limits including host controller limits, device
+ *	blacklist, etc...
+ *
+ *	LOCKING:
+ *	None.
+ */
+static void ata_dev_xfermask(struct ata_device *dev)
+{
+	struct ata_port *ap = dev->ap;
+	struct ata_host_set *hs = ap->host_set;
+	unsigned long xfer_mask;
+
+	/* controller modes available */
+	xfer_mask = ata_pack_xfermask(ap->pio_mask,
+				      ap->mwdma_mask, ap->udma_mask);
+
+	/* Apply cable rule here.  Don't apply it early because when
+	 * we handle hot plug the cable type can itself change.
+	 */
+	if (ap->cbl == ATA_CBL_PATA40)
+		xfer_mask &= ~(0xF8 << ATA_SHIFT_UDMA);
+
+	xfer_mask &= ata_pack_xfermask(dev->pio_mask,
+				       dev->mwdma_mask, dev->udma_mask);
+	xfer_mask &= ata_id_xfermask(dev->id);
+
+	if (ata_dma_blacklisted(dev)) {
+		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
+		ata_dev_printk(dev, KERN_WARNING,
+			       "device is on DMA blacklist, disabling DMA\n");
+	}
+
+	if ((hs->flags & ATA_HOST_SIMPLEX) && hs->simplex_claimed) {
+		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
+		ata_dev_printk(dev, KERN_WARNING, "simplex DMA is claimed by "
+			       "other device, disabling DMA\n");
+	}
+
+	if (ap->ops->mode_filter)
+		xfer_mask = ap->ops->mode_filter(ap, dev, xfer_mask);
+
+	ata_unpack_xfermask(xfer_mask, &dev->pio_mask,
+			    &dev->mwdma_mask, &dev->udma_mask);
+}
+
+/**
+ *	ata_dev_set_xfermode - Issue SET FEATURES - XFER MODE command
+ *	@dev: Device to which command will be sent
+ *
+ *	Issue SET FEATURES - XFER MODE command to device @dev
+ *	on port @ap.
+ *
+ *	LOCKING:
+ *	PCI/etc. bus probe sem.
+ *
+ *	RETURNS:
+ *	0 on success, AC_ERR_* mask otherwise.
+ */
+
+static unsigned int ata_dev_set_xfermode(struct ata_device *dev)
+{
+	struct ata_taskfile tf;
+	unsigned int err_mask;
+
+	/* set up set-features taskfile */
+	DPRINTK("set features - xfer mode\n");
+
+	ata_tf_init(dev, &tf);
+	tf.command = ATA_CMD_SET_FEATURES;
+	tf.feature = SETFEATURES_XFER;
+	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
+	tf.protocol = ATA_PROT_NODATA;
+	tf.nsect = dev->xfer_mode;
+
+	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0);
+
+	DPRINTK("EXIT, err_mask=%x\n", err_mask);
+	return err_mask;
+}
+
+/**
+ *	ata_dev_init_params - Issue INIT DEV PARAMS command
+ *	@dev: Device to which command will be sent
+ *	@heads: Number of heads (taskfile parameter)
+ *	@sectors: Number of sectors (taskfile parameter)
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep)
+ *
+ *	RETURNS:
+ *	0 on success, AC_ERR_* mask otherwise.
+ */
+static unsigned int ata_dev_init_params(struct ata_device *dev,
+					u16 heads, u16 sectors)
+{
+	struct ata_taskfile tf;
+	unsigned int err_mask;
+
+	/* Number of sectors per track 1-255. Number of heads 1-16 */
+	if (sectors < 1 || sectors > 255 || heads < 1 || heads > 16)
+		return AC_ERR_INVALID;
+
+	/* set up init dev params taskfile */
+	DPRINTK("init dev params \n");
+
+	ata_tf_init(dev, &tf);
+	tf.command = ATA_CMD_INIT_DEV_PARAMS;
+	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
+	tf.protocol = ATA_PROT_NODATA;
+	tf.nsect = sectors;
+	tf.device |= (heads - 1) & 0x0f; /* max head = num. of heads - 1 */
+
+	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0);
+
+	DPRINTK("EXIT, err_mask=%x\n", err_mask);
+	return err_mask;
+}
+
+/**
+ *	ata_sg_clean - Unmap DMA memory associated with command
+ *	@qc: Command containing DMA memory to be released
+ *
+ *	Unmap all mapped DMA memory associated with this command.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ */
+
+static void ata_sg_clean(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+	struct scatterlist *sg = qc->__sg;
+	int dir = qc->dma_dir;
+	void *pad_buf = NULL;
+
+	WARN_ON(!(qc->flags & ATA_QCFLAG_DMAMAP));
+	WARN_ON(sg == NULL);
+
+	if (qc->flags & ATA_QCFLAG_SINGLE)
+		WARN_ON(qc->n_elem > 1);
+
+	VPRINTK("unmapping %u sg elements\n", qc->n_elem);
+
+	/* if we padded the buffer out to 32-bit bound, and data
+	 * xfer direction is from-device, we must copy from the
+	 * pad buffer back into the supplied buffer
+	 */
+	if (qc->pad_len && !(qc->tf.flags & ATA_TFLAG_WRITE))
+		pad_buf = ap->pad + (qc->tag * ATA_DMA_PAD_SZ);
+
+	if (qc->flags & ATA_QCFLAG_SG) {
+		if (qc->n_elem)
+			dma_unmap_sg(ap->dev, sg, qc->n_elem, dir);
+		/* restore last sg */
+		sg[qc->orig_n_elem - 1].length += qc->pad_len;
+		if (pad_buf) {
+			struct scatterlist *psg = &qc->pad_sgent;
+			void *addr = kmap_atomic(psg->page, KM_IRQ0);
+			memcpy(addr + psg->offset, pad_buf, qc->pad_len);
+			kunmap_atomic(addr, KM_IRQ0);
+		}
+	} else {
+		if (qc->n_elem)
+			dma_unmap_single(ap->dev,
+				sg_dma_address(&sg[0]), sg_dma_len(&sg[0]),
+				dir);
+		/* restore sg */
+		sg->length += qc->pad_len;
+		if (pad_buf)
+			memcpy(qc->buf_virt + sg->length - qc->pad_len,
+			       pad_buf, qc->pad_len);
+	}
+
+	qc->flags &= ~ATA_QCFLAG_DMAMAP;
+	qc->__sg = NULL;
+}
+
+/**
+ *	ata_fill_sg - Fill PCI IDE PRD table
+ *	@qc: Metadata associated with taskfile to be transferred
+ *
+ *	Fill PCI IDE PRD (scatter-gather) table with segments
+ *	associated with the current disk command.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ *
+ */
+static void ata_fill_sg(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+	struct scatterlist *sg;
+	unsigned int idx;
+
+	WARN_ON(qc->__sg == NULL);
+	WARN_ON(qc->n_elem == 0 && qc->pad_len == 0);
+
+	idx = 0;
+	ata_for_each_sg(sg, qc) {
+		u32 addr, offset;
+		u32 sg_len, len;
+
+		/* determine if physical DMA addr spans 64K boundary.
+		 * Note h/w doesn't support 64-bit, so we unconditionally
+		 * truncate dma_addr_t to u32.
+		 */
+		addr = (u32) sg_dma_address(sg);
+		sg_len = sg_dma_len(sg);
+
+		while (sg_len) {
+			offset = addr & 0xffff;
+			len = sg_len;
+			if ((offset + sg_len) > 0x10000)
+				len = 0x10000 - offset;
+
+			ap->prd[idx].addr = cpu_to_le32(addr);
+			ap->prd[idx].flags_len = cpu_to_le32(len & 0xffff);
+			VPRINTK("PRD[%u] = (0x%X, 0x%X)\n", idx, addr, len);
+
+			idx++;
+			sg_len -= len;
+			addr += len;
+		}
+	}
+
+	if (idx)
+		ap->prd[idx - 1].flags_len |= cpu_to_le32(ATA_PRD_EOT);
+}
+/**
+ *	ata_check_atapi_dma - Check whether ATAPI DMA can be supported
+ *	@qc: Metadata associated with taskfile to check
+ *
+ *	Allow low-level driver to filter ATA PACKET commands, returning
+ *	a status indicating whether or not it is OK to use DMA for the
+ *	supplied PACKET command.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ *
+ *	RETURNS: 0 when ATAPI DMA can be used
+ *               nonzero otherwise
+ */
+int ata_check_atapi_dma(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+	int rc = 0; /* Assume ATAPI DMA is OK by default */
+
+	if (ap->ops->check_atapi_dma)
+		rc = ap->ops->check_atapi_dma(qc);
+
+	return rc;
+}
+/**
+ *	ata_qc_prep - Prepare taskfile for submission
+ *	@qc: Metadata associated with taskfile to be prepared
+ *
+ *	Prepare ATA taskfile for submission.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ */
+void ata_qc_prep(struct ata_queued_cmd *qc)
+{
+	if (!(qc->flags & ATA_QCFLAG_DMAMAP))
+		return;
+
+	ata_fill_sg(qc);
+}
+
+void ata_noop_qc_prep(struct ata_queued_cmd *qc) { }
+
+/**
+ *	ata_sg_init_one - Associate command with memory buffer
+ *	@qc: Command to be associated
+ *	@buf: Memory buffer
+ *	@buflen: Length of memory buffer, in bytes.
+ *
+ *	Initialize the data-related elements of queued_cmd @qc
+ *	to point to a single memory buffer, @buf of byte length @buflen.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ */
+
+void ata_sg_init_one(struct ata_queued_cmd *qc, void *buf, unsigned int buflen)
+{
+	struct scatterlist *sg;
+
+	qc->flags |= ATA_QCFLAG_SINGLE;
+
+	memset(&qc->sgent, 0, sizeof(qc->sgent));
+	qc->__sg = &qc->sgent;
+	qc->n_elem = 1;
+	qc->orig_n_elem = 1;
+	qc->buf_virt = buf;
+	qc->nbytes = buflen;
+
+	sg = qc->__sg;
+	sg_init_one(sg, buf, buflen);
+}
+
+/**
+ *	ata_sg_init - Associate command with scatter-gather table.
+ *	@qc: Command to be associated
+ *	@sg: Scatter-gather table.
+ *	@n_elem: Number of elements in s/g table.
+ *
+ *	Initialize the data-related elements of queued_cmd @qc
+ *	to point to a scatter-gather table @sg, containing @n_elem
+ *	elements.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ */
+
+void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
+		 unsigned int n_elem)
+{
+	qc->flags |= ATA_QCFLAG_SG;
+	qc->__sg = sg;
+	qc->n_elem = n_elem;
+	qc->orig_n_elem = n_elem;
+}
+
+/**
+ *	ata_sg_setup_one - DMA-map the memory buffer associated with a command.
+ *	@qc: Command with memory buffer to be mapped.
+ *
+ *	DMA-map the memory buffer associated with queued_cmd @qc.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ *
+ *	RETURNS:
+ *	Zero on success, negative on error.
+ */
+
+static int ata_sg_setup_one(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+	int dir = qc->dma_dir;
+	struct scatterlist *sg = qc->__sg;
+	dma_addr_t dma_address;
+	int trim_sg = 0;
+
+	/* we must lengthen transfers to end on a 32-bit boundary */
+	qc->pad_len = sg->length & 3;
+	if (qc->pad_len) {
+		void *pad_buf = ap->pad + (qc->tag * ATA_DMA_PAD_SZ);
+		struct scatterlist *psg = &qc->pad_sgent;
+
+		WARN_ON(qc->dev->class != ATA_DEV_ATAPI);
+
+		memset(pad_buf, 0, ATA_DMA_PAD_SZ);
+
+		if (qc->tf.flags & ATA_TFLAG_WRITE)
+			memcpy(pad_buf, qc->buf_virt + sg->length - qc->pad_len,
+			       qc->pad_len);
+
+		sg_dma_address(psg) = ap->pad_dma + (qc->tag * ATA_DMA_PAD_SZ);
+		sg_dma_len(psg) = ATA_DMA_PAD_SZ;
+		/* trim sg */
+		sg->length -= qc->pad_len;
+		if (sg->length == 0)
+			trim_sg = 1;
+
+		DPRINTK("padding done, sg->length=%u pad_len=%u\n",
+			sg->length, qc->pad_len);
+	}
+
+	if (trim_sg) {
+		qc->n_elem--;
+		goto skip_map;
+	}
+
+	dma_address = dma_map_single(ap->dev, qc->buf_virt,
+				     sg->length, dir);
+	if (dma_mapping_error(dma_address)) {
+		/* restore sg */
+		sg->length += qc->pad_len;
+		return -1;
+	}
+
+	sg_dma_address(sg) = dma_address;
+	sg_dma_len(sg) = sg->length;
+
+skip_map:
+	DPRINTK("mapped buffer of %d bytes for %s\n", sg_dma_len(sg),
+		qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");
+
+	return 0;
+}
+
+/**
+ *	ata_sg_setup - DMA-map the scatter-gather table associated with a command.
+ *	@qc: Command with scatter-gather table to be mapped.
+ *
+ *	DMA-map the scatter-gather table associated with queued_cmd @qc.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ *
+ *	RETURNS:
+ *	Zero on success, negative on error.
+ *
+ */
+
+static int ata_sg_setup(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+	struct scatterlist *sg = qc->__sg;
+	struct scatterlist *lsg = &sg[qc->n_elem - 1];
+	int n_elem, pre_n_elem, dir, trim_sg = 0;
+
+	VPRINTK("ENTER, ata%u\n", ap->id);
+	WARN_ON(!(qc->flags & ATA_QCFLAG_SG));
+
+	/* we must lengthen transfers to end on a 32-bit boundary */
+	qc->pad_len = lsg->length & 3;
+	if (qc->pad_len) {
+		void *pad_buf = ap->pad + (qc->tag * ATA_DMA_PAD_SZ);
+		struct scatterlist *psg = &qc->pad_sgent;
+		unsigned int offset;
+
+		WARN_ON(qc->dev->class != ATA_DEV_ATAPI);
+
+		memset(pad_buf, 0, ATA_DMA_PAD_SZ);
+
+		/*
+		 * psg->page/offset are used to copy to-be-written
+		 * data in this function or read data in ata_sg_clean.
+		 */
+		offset = lsg->offset + lsg->length - qc->pad_len;
+		psg->page = nth_page(lsg->page, offset >> PAGE_SHIFT);
+		psg->offset = offset_in_page(offset);
+
+		if (qc->tf.flags & ATA_TFLAG_WRITE) {
+			void *addr = kmap_atomic(psg->page, KM_IRQ0);
+			memcpy(pad_buf, addr + psg->offset, qc->pad_len);
+			kunmap_atomic(addr, KM_IRQ0);
+		}
+
+		sg_dma_address(psg) = ap->pad_dma + (qc->tag * ATA_DMA_PAD_SZ);
+		sg_dma_len(psg) = ATA_DMA_PAD_SZ;
+		/* trim last sg */
+		lsg->length -= qc->pad_len;
+		if (lsg->length == 0)
+			trim_sg = 1;
+
+		DPRINTK("padding done, sg[%d].length=%u pad_len=%u\n",
+			qc->n_elem - 1, lsg->length, qc->pad_len);
+	}
+
+	pre_n_elem = qc->n_elem;
+	if (trim_sg && pre_n_elem)
+		pre_n_elem--;
+
+	if (!pre_n_elem) {
+		n_elem = 0;
+		goto skip_map;
+	}
+
+	dir = qc->dma_dir;
+	n_elem = dma_map_sg(ap->dev, sg, pre_n_elem, dir);
+	if (n_elem < 1) {
+		/* restore last sg */
+		lsg->length += qc->pad_len;
+		return -1;
+	}
+
+	DPRINTK("%d sg elements mapped\n", n_elem);
+
+skip_map:
+	qc->n_elem = n_elem;
+
+	return 0;
+}
+
+/**
+ *	swap_buf_le16 - swap halves of 16-bit words in place
+ *	@buf:  Buffer to swap
+ *	@buf_words:  Number of 16-bit words in buffer.
+ *
+ *	Swap halves of 16-bit words if needed to convert from
+ *	little-endian byte order to native cpu byte order, or
+ *	vice-versa.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ */
+void swap_buf_le16(u16 *buf, unsigned int buf_words)
+{
+#ifdef __BIG_ENDIAN
+	unsigned int i;
+
+	for (i = 0; i < buf_words; i++)
+		buf[i] = le16_to_cpu(buf[i]);
+#endif /* __BIG_ENDIAN */
+}
+
+/**
+ *	ata_mmio_data_xfer - Transfer data by MMIO
+ *	@adev: device for this I/O
+ *	@buf: data buffer
+ *	@buflen: buffer length
+ *	@write_data: read/write
+ *
+ *	Transfer data from/to the device data register by MMIO.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ */
+
+void ata_mmio_data_xfer(struct ata_device *adev, unsigned char *buf,
+			unsigned int buflen, int write_data)
+{
+	struct ata_port *ap = adev->ap;
+	unsigned int i;
+	unsigned int words = buflen >> 1;
+	u16 *buf16 = (u16 *) buf;
+	void __iomem *mmio = (void __iomem *)ap->ioaddr.data_addr;
+
+	/* Transfer multiple of 2 bytes */
+	if (write_data) {
+		for (i = 0; i < words; i++)
+			writew(le16_to_cpu(buf16[i]), mmio);
+	} else {
+		for (i = 0; i < words; i++)
+			buf16[i] = cpu_to_le16(readw(mmio));
+	}
+
+	/* Transfer trailing 1 byte, if any. */
+	if (unlikely(buflen & 0x01)) {
+		u16 align_buf[1] = { 0 };
+		unsigned char *trailing_buf = buf + buflen - 1;
+
+		if (write_data) {
+			memcpy(align_buf, trailing_buf, 1);
+			writew(le16_to_cpu(align_buf[0]), mmio);
+		} else {
+			align_buf[0] = cpu_to_le16(readw(mmio));
+			memcpy(trailing_buf, align_buf, 1);
+		}
+	}
+}
+
+/**
+ *	ata_pio_data_xfer - Transfer data by PIO
+ *	@adev: device to target
+ *	@buf: data buffer
+ *	@buflen: buffer length
+ *	@write_data: read/write
+ *
+ *	Transfer data from/to the device data register by PIO.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ */
+
+void ata_pio_data_xfer(struct ata_device *adev, unsigned char *buf,
+		       unsigned int buflen, int write_data)
+{
+	struct ata_port *ap = adev->ap;
+	unsigned int words = buflen >> 1;
+
+	/* Transfer multiple of 2 bytes */
+	if (write_data)
+		outsw(ap->ioaddr.data_addr, buf, words);
+	else
+		insw(ap->ioaddr.data_addr, buf, words);
+
+	/* Transfer trailing 1 byte, if any. */
+	if (unlikely(buflen & 0x01)) {
+		u16 align_buf[1] = { 0 };
+		unsigned char *trailing_buf = buf + buflen - 1;
+
+		if (write_data) {
+			memcpy(align_buf, trailing_buf, 1);
+			outw(le16_to_cpu(align_buf[0]), ap->ioaddr.data_addr);
+		} else {
+			align_buf[0] = cpu_to_le16(inw(ap->ioaddr.data_addr));
+			memcpy(trailing_buf, align_buf, 1);
+		}
+	}
+}
+
+/**
+ *	ata_pio_data_xfer_noirq - Transfer data by PIO
+ *	@adev: device to target
+ *	@buf: data buffer
+ *	@buflen: buffer length
+ *	@write_data: read/write
+ *
+ *	Transfer data from/to the device data register by PIO. Do the
+ *	transfer with interrupts disabled.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ */
+
+void ata_pio_data_xfer_noirq(struct ata_device *adev, unsigned char *buf,
+				    unsigned int buflen, int write_data)
+{
+	unsigned long flags;
+	local_irq_save(flags);
+	ata_pio_data_xfer(adev, buf, buflen, write_data);
+	local_irq_restore(flags);
+}
+
+
+/**
+ *	ata_pio_sector - Transfer ATA_SECT_SIZE (512 bytes) of data.
+ *	@qc: Command on going
+ *
+ *	Transfer ATA_SECT_SIZE of data from/to the ATA device.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ */
+
+static void ata_pio_sector(struct ata_queued_cmd *qc)
+{
+	int do_write = (qc->tf.flags & ATA_TFLAG_WRITE);
+	struct scatterlist *sg = qc->__sg;
+	struct ata_port *ap = qc->ap;
+	struct page *page;
+	unsigned int offset;
+	unsigned char *buf;
+
+	if (qc->cursect == (qc->nsect - 1))
+		ap->hsm_task_state = HSM_ST_LAST;
+
+	page = sg[qc->cursg].page;
+	offset = sg[qc->cursg].offset + qc->cursg_ofs * ATA_SECT_SIZE;
+
+	/* get the current page and offset */
+	page = nth_page(page, (offset >> PAGE_SHIFT));
+	offset %= PAGE_SIZE;
+
+	DPRINTK("data %s\n", qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");
+
+	if (PageHighMem(page)) {
+		unsigned long flags;
+
+		/* FIXME: use a bounce buffer */
+		local_irq_save(flags);
+		buf = kmap_atomic(page, KM_IRQ0);
+
+		/* do the actual data transfer */
+		ap->ops->data_xfer(qc->dev, buf + offset, ATA_SECT_SIZE, do_write);
+
+		kunmap_atomic(buf, KM_IRQ0);
+		local_irq_restore(flags);
+	} else {
+		buf = page_address(page);
+		ap->ops->data_xfer(qc->dev, buf + offset, ATA_SECT_SIZE, do_write);
+	}
+
+	qc->cursect++;
+	qc->cursg_ofs++;
+
+	if ((qc->cursg_ofs * ATA_SECT_SIZE) == (&sg[qc->cursg])->length) {
+		qc->cursg++;
+		qc->cursg_ofs = 0;
+	}
+}
+
+/**
+ *	ata_pio_sectors - Transfer one or many 512-byte sectors.
+ *	@qc: Command on going
+ *
+ *	Transfer one or many ATA_SECT_SIZE of data from/to the
+ *	ATA device for the DRQ request.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ */
+
+static void ata_pio_sectors(struct ata_queued_cmd *qc)
+{
+	if (is_multi_taskfile(&qc->tf)) {
+		/* READ/WRITE MULTIPLE */
+		unsigned int nsect;
+
+		WARN_ON(qc->dev->multi_count == 0);
+
+		nsect = min(qc->nsect - qc->cursect, qc->dev->multi_count);
+		while (nsect--)
+			ata_pio_sector(qc);
+	} else
+		ata_pio_sector(qc);
+}
+
+/**
+ *	atapi_send_cdb - Write CDB bytes to hardware
+ *	@ap: Port to which ATAPI device is attached.
+ *	@qc: Taskfile currently active
+ *
+ *	When device has indicated its readiness to accept
+ *	a CDB, this function is called.  Send the CDB.
+ *
+ *	LOCKING:
+ *	caller.
+ */
+
+static void atapi_send_cdb(struct ata_port *ap, struct ata_queued_cmd *qc)
+{
+	/* send SCSI cdb */
+	DPRINTK("send cdb\n");
+	WARN_ON(qc->dev->cdb_len < 12);
+
+	ap->ops->data_xfer(qc->dev, qc->cdb, qc->dev->cdb_len, 1);
+	ata_altstatus(ap); /* flush */
+
+	switch (qc->tf.protocol) {
+	case ATA_PROT_ATAPI:
+		ap->hsm_task_state = HSM_ST;
+		break;
+	case ATA_PROT_ATAPI_NODATA:
+		ap->hsm_task_state = HSM_ST_LAST;
+		break;
+	case ATA_PROT_ATAPI_DMA:
+		ap->hsm_task_state = HSM_ST_LAST;
+		/* initiate bmdma */
+		ap->ops->bmdma_start(qc);
+		break;
+	}
+}
+
+/**
+ *	__atapi_pio_bytes - Transfer data from/to the ATAPI device.
+ *	@qc: Command on going
+ *	@bytes: number of bytes
+ *
+ *	Transfer Transfer data from/to the ATAPI device.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ *
+ */
+
+static void __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes)
+{
+	int do_write = (qc->tf.flags & ATA_TFLAG_WRITE);
+	struct scatterlist *sg = qc->__sg;
+	struct ata_port *ap = qc->ap;
+	struct page *page;
+	unsigned char *buf;
+	unsigned int offset, count;
+
+	if (qc->curbytes + bytes >= qc->nbytes)
+		ap->hsm_task_state = HSM_ST_LAST;
+
+next_sg:
+	if (unlikely(qc->cursg >= qc->n_elem)) {
+		/*
+		 * The end of qc->sg is reached and the device expects
+		 * more data to transfer. In order not to overrun qc->sg
+		 * and fulfill length specified in the byte count register,
+		 *    - for read case, discard trailing data from the device
+		 *    - for write case, padding zero data to the device
+		 */
+		u16 pad_buf[1] = { 0 };
+		unsigned int words = bytes >> 1;
+		unsigned int i;
+
+		if (words) /* warning if bytes > 1 */
+			ata_dev_printk(qc->dev, KERN_WARNING,
+				       "%u bytes trailing data\n", bytes);
+
+		for (i = 0; i < words; i++)
+			ap->ops->data_xfer(qc->dev, (unsigned char*)pad_buf, 2, do_write);
+
+		ap->hsm_task_state = HSM_ST_LAST;
+		return;
+	}
+
+	sg = &qc->__sg[qc->cursg];
+
+	page = sg->page;
+	offset = sg->offset + qc->cursg_ofs;
+
+	/* get the current page and offset */
+	page = nth_page(page, (offset >> PAGE_SHIFT));
+	offset %= PAGE_SIZE;
+
+	/* don't overrun current sg */
+	count = min(sg->length - qc->cursg_ofs, bytes);
+
+	/* don't cross page boundaries */
+	count = min(count, (unsigned int)PAGE_SIZE - offset);
+
+	DPRINTK("data %s\n", qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");
+
+	if (PageHighMem(page)) {
+		unsigned long flags;
+
+		/* FIXME: use bounce buffer */
+		local_irq_save(flags);
+		buf = kmap_atomic(page, KM_IRQ0);
+
+		/* do the actual data transfer */
+		ap->ops->data_xfer(qc->dev,  buf + offset, count, do_write);
+
+		kunmap_atomic(buf, KM_IRQ0);
+		local_irq_restore(flags);
+	} else {
+		buf = page_address(page);
+		ap->ops->data_xfer(qc->dev,  buf + offset, count, do_write);
+	}
+
+	bytes -= count;
+	qc->curbytes += count;
+	qc->cursg_ofs += count;
+
+	if (qc->cursg_ofs == sg->length) {
+		qc->cursg++;
+		qc->cursg_ofs = 0;
+	}
+
+	if (bytes)
+		goto next_sg;
+}
+
+/**
+ *	atapi_pio_bytes - Transfer data from/to the ATAPI device.
+ *	@qc: Command on going
+ *
+ *	Transfer Transfer data from/to the ATAPI device.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ */
+
+static void atapi_pio_bytes(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+	struct ata_device *dev = qc->dev;
+	unsigned int ireason, bc_lo, bc_hi, bytes;
+	int i_write, do_write = (qc->tf.flags & ATA_TFLAG_WRITE) ? 1 : 0;
+
+	/* Abuse qc->result_tf for temp storage of intermediate TF
+	 * here to save some kernel stack usage.
+	 * For normal completion, qc->result_tf is not relevant. For
+	 * error, qc->result_tf is later overwritten by ata_qc_complete().
+	 * So, the correctness of qc->result_tf is not affected.
+	 */
+	ap->ops->tf_read(ap, &qc->result_tf);
+	ireason = qc->result_tf.nsect;
+	bc_lo = qc->result_tf.lbam;
+	bc_hi = qc->result_tf.lbah;
+	bytes = (bc_hi << 8) | bc_lo;
+
+	/* shall be cleared to zero, indicating xfer of data */
+	if (ireason & (1 << 0))
+		goto err_out;
+
+	/* make sure transfer direction matches expected */
+	i_write = ((ireason & (1 << 1)) == 0) ? 1 : 0;
+	if (do_write != i_write)
+		goto err_out;
+
+	VPRINTK("ata%u: xfering %d bytes\n", ap->id, bytes);
+
+	__atapi_pio_bytes(qc, bytes);
+
+	return;
+
+err_out:
+	ata_dev_printk(dev, KERN_INFO, "ATAPI check failed\n");
+	qc->err_mask |= AC_ERR_HSM;
+	ap->hsm_task_state = HSM_ST_ERR;
+}
+
+/**
+ *	ata_hsm_ok_in_wq - Check if the qc can be handled in the workqueue.
+ *	@ap: the target ata_port
+ *	@qc: qc on going
+ *
+ *	RETURNS:
+ *	1 if ok in workqueue, 0 otherwise.
+ */
+
+static inline int ata_hsm_ok_in_wq(struct ata_port *ap, struct ata_queued_cmd *qc)
+{
+	if (qc->tf.flags & ATA_TFLAG_POLLING)
+		return 1;
+
+	if (ap->hsm_task_state == HSM_ST_FIRST) {
+		if (qc->tf.protocol == ATA_PROT_PIO &&
+		    (qc->tf.flags & ATA_TFLAG_WRITE))
+		    return 1;
+
+		if (is_atapi_taskfile(&qc->tf) &&
+		    !(qc->dev->flags & ATA_DFLAG_CDB_INTR))
+			return 1;
+	}
+
+	return 0;
+}
+
+/**
+ *	ata_hsm_qc_complete - finish a qc running on standard HSM
+ *	@qc: Command to complete
+ *	@in_wq: 1 if called from workqueue, 0 otherwise
+ *
+ *	Finish @qc which is running on standard HSM.
+ *
+ *	LOCKING:
+ *	If @in_wq is zero, spin_lock_irqsave(host_set lock).
+ *	Otherwise, none on entry and grabs host lock.
+ */
+static void ata_hsm_qc_complete(struct ata_queued_cmd *qc, int in_wq)
+{
+	struct ata_port *ap = qc->ap;
+	unsigned long flags;
+
+	if (ap->ops->error_handler) {
+		if (in_wq) {
+			spin_lock_irqsave(ap->lock, flags);
+
+			/* EH might have kicked in while host_set lock
+			 * is released.
+			 */
+			qc = ata_qc_from_tag(ap, qc->tag);
+			if (qc) {
+				if (likely(!(qc->err_mask & AC_ERR_HSM))) {
+					ata_irq_on(ap);
+					ata_qc_complete(qc);
+				} else
+					ata_port_freeze(ap);
+			}
+
+			spin_unlock_irqrestore(ap->lock, flags);
+		} else {
+			if (likely(!(qc->err_mask & AC_ERR_HSM)))
+				ata_qc_complete(qc);
+			else
+				ata_port_freeze(ap);
+		}
+	} else {
+		if (in_wq) {
+			spin_lock_irqsave(ap->lock, flags);
+			ata_irq_on(ap);
+			ata_qc_complete(qc);
+			spin_unlock_irqrestore(ap->lock, flags);
+		} else
+			ata_qc_complete(qc);
+	}
+
+	ata_altstatus(ap); /* flush */
+}
+
+/**
+ *	ata_hsm_move - move the HSM to the next state.
+ *	@ap: the target ata_port
+ *	@qc: qc on going
+ *	@status: current device status
+ *	@in_wq: 1 if called from workqueue, 0 otherwise
+ *
+ *	RETURNS:
+ *	1 when poll next status needed, 0 otherwise.
+ */
+int ata_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc,
+		 u8 status, int in_wq)
+{
+	unsigned long flags = 0;
+	int poll_next;
+
+	WARN_ON((qc->flags & ATA_QCFLAG_ACTIVE) == 0);
+
+	/* Make sure ata_qc_issue_prot() does not throw things
+	 * like DMA polling into the workqueue. Notice that
+	 * in_wq is not equivalent to (qc->tf.flags & ATA_TFLAG_POLLING).
+	 */
+	WARN_ON(in_wq != ata_hsm_ok_in_wq(ap, qc));
+
+fsm_start:
+	DPRINTK("ata%u: protocol %d task_state %d (dev_stat 0x%X)\n",
+		ap->id, qc->tf.protocol, ap->hsm_task_state, status);
+
+	switch (ap->hsm_task_state) {
+	case HSM_ST_FIRST:
+		/* Send first data block or PACKET CDB */
+
+		/* If polling, we will stay in the work queue after
+		 * sending the data. Otherwise, interrupt handler
+		 * takes over after sending the data.
+		 */
+		poll_next = (qc->tf.flags & ATA_TFLAG_POLLING);
+
+		/* check device status */
+		if (unlikely((status & ATA_DRQ) == 0)) {
+			/* handle BSY=0, DRQ=0 as error */
+			if (likely(status & (ATA_ERR | ATA_DF)))
+				/* device stops HSM for abort/error */
+				qc->err_mask |= AC_ERR_DEV;
+			else
+				/* HSM violation. Let EH handle this */
+				qc->err_mask |= AC_ERR_HSM;
+
+			ap->hsm_task_state = HSM_ST_ERR;
+			goto fsm_start;
+		}
+
+		/* Device should not ask for data transfer (DRQ=1)
+		 * when it finds something wrong.
+		 * We ignore DRQ here and stop the HSM by
+		 * changing hsm_task_state to HSM_ST_ERR and
+		 * let the EH abort the command or reset the device.
+		 */
+		if (unlikely(status & (ATA_ERR | ATA_DF))) {
+			printk(KERN_WARNING "ata%d: DRQ=1 with device error, dev_stat 0x%X\n",
+			       ap->id, status);
+			qc->err_mask |= AC_ERR_HSM;
+			ap->hsm_task_state = HSM_ST_ERR;
+			goto fsm_start;
+		}
+
+		/* Send the CDB (atapi) or the first data block (ata pio out).
+		 * During the state transition, interrupt handler shouldn't
+		 * be invoked before the data transfer is complete and
+		 * hsm_task_state is changed. Hence, the following locking.
+		 */
+		if (in_wq)
+			spin_lock_irqsave(ap->lock, flags);
+
+		if (qc->tf.protocol == ATA_PROT_PIO) {
+			/* PIO data out protocol.
+			 * send first data block.
+			 */
+
+			/* ata_pio_sectors() might change the state
+			 * to HSM_ST_LAST. so, the state is changed here
+			 * before ata_pio_sectors().
+			 */
+			ap->hsm_task_state = HSM_ST;
+			ata_pio_sectors(qc);
+			ata_altstatus(ap); /* flush */
+		} else
+			/* send CDB */
+			atapi_send_cdb(ap, qc);
+
+		if (in_wq)
+			spin_unlock_irqrestore(ap->lock, flags);
+
+		/* if polling, ata_pio_task() handles the rest.
+		 * otherwise, interrupt handler takes over from here.
+		 */
+		break;
+
+	case HSM_ST:
+		/* complete command or read/write the data register */
+		if (qc->tf.protocol == ATA_PROT_ATAPI) {
+			/* ATAPI PIO protocol */
+			if ((status & ATA_DRQ) == 0) {
+				/* No more data to transfer or device error.
+				 * Device error will be tagged in HSM_ST_LAST.
+				 */
+				ap->hsm_task_state = HSM_ST_LAST;
+				goto fsm_start;
+			}
+
+			/* Device should not ask for data transfer (DRQ=1)
+			 * when it finds something wrong.
+			 * We ignore DRQ here and stop the HSM by
+			 * changing hsm_task_state to HSM_ST_ERR and
+			 * let the EH abort the command or reset the device.
+			 */
+			if (unlikely(status & (ATA_ERR | ATA_DF))) {
+				printk(KERN_WARNING "ata%d: DRQ=1 with device error, dev_stat 0x%X\n",
+				       ap->id, status);
+				qc->err_mask |= AC_ERR_HSM;
+				ap->hsm_task_state = HSM_ST_ERR;
+				goto fsm_start;
+			}
+
+			atapi_pio_bytes(qc);
+
+			if (unlikely(ap->hsm_task_state == HSM_ST_ERR))
+				/* bad ireason reported by device */
+				goto fsm_start;
+
+		} else {
+			/* ATA PIO protocol */
+			if (unlikely((status & ATA_DRQ) == 0)) {
+				/* handle BSY=0, DRQ=0 as error */
+				if (likely(status & (ATA_ERR | ATA_DF)))
+					/* device stops HSM for abort/error */
+					qc->err_mask |= AC_ERR_DEV;
+				else
+					/* HSM violation. Let EH handle this */
+					qc->err_mask |= AC_ERR_HSM;
+
+				ap->hsm_task_state = HSM_ST_ERR;
+				goto fsm_start;
+			}
+
+			/* For PIO reads, some devices may ask for
+			 * data transfer (DRQ=1) alone with ERR=1.
+			 * We respect DRQ here and transfer one
+			 * block of junk data before changing the
+			 * hsm_task_state to HSM_ST_ERR.
+			 *
+			 * For PIO writes, ERR=1 DRQ=1 doesn't make
+			 * sense since the data block has been
+			 * transferred to the device.
+			 */
+			if (unlikely(status & (ATA_ERR | ATA_DF))) {
+				/* data might be corrputed */
+				qc->err_mask |= AC_ERR_DEV;
+
+				if (!(qc->tf.flags & ATA_TFLAG_WRITE)) {
+					ata_pio_sectors(qc);
+					ata_altstatus(ap);
+					status = ata_wait_idle(ap);
+				}
+
+				if (status & (ATA_BUSY | ATA_DRQ))
+					qc->err_mask |= AC_ERR_HSM;
+
+				/* ata_pio_sectors() might change the
+				 * state to HSM_ST_LAST. so, the state
+				 * is changed after ata_pio_sectors().
+				 */
+				ap->hsm_task_state = HSM_ST_ERR;
+				goto fsm_start;
+			}
+
+			ata_pio_sectors(qc);
+
+			if (ap->hsm_task_state == HSM_ST_LAST &&
+			    (!(qc->tf.flags & ATA_TFLAG_WRITE))) {
+				/* all data read */
+				ata_altstatus(ap);
+				status = ata_wait_idle(ap);
+				goto fsm_start;
+			}
+		}
+
+		ata_altstatus(ap); /* flush */
+		poll_next = 1;
+		break;
+
+	case HSM_ST_LAST:
+		if (unlikely(!ata_ok(status))) {
+			qc->err_mask |= __ac_err_mask(status);
+			ap->hsm_task_state = HSM_ST_ERR;
+			goto fsm_start;
+		}
+
+		/* no more data to transfer */
+		DPRINTK("ata%u: dev %u command complete, drv_stat 0x%x\n",
+			ap->id, qc->dev->devno, status);
+
+		WARN_ON(qc->err_mask);
+
+		ap->hsm_task_state = HSM_ST_IDLE;
+
+		/* complete taskfile transaction */
+		ata_hsm_qc_complete(qc, in_wq);
+
+		poll_next = 0;
+		break;
+
+	case HSM_ST_ERR:
+		/* make sure qc->err_mask is available to
+		 * know what's wrong and recover
+		 */
+		WARN_ON(qc->err_mask == 0);
+
+		ap->hsm_task_state = HSM_ST_IDLE;
+
+		/* complete taskfile transaction */
+		ata_hsm_qc_complete(qc, in_wq);
+
+		poll_next = 0;
+		break;
+	default:
+		poll_next = 0;
+		BUG();
+	}
+
+	return poll_next;
+}
+
+static void ata_pio_task(void *_data)
+{
+	struct ata_queued_cmd *qc = _data;
+	struct ata_port *ap = qc->ap;
+	u8 status;
+	int poll_next;
+
+fsm_start:
+	WARN_ON(ap->hsm_task_state == HSM_ST_IDLE);
+
+	/*
+	 * This is purely heuristic.  This is a fast path.
+	 * Sometimes when we enter, BSY will be cleared in
+	 * a chk-status or two.  If not, the drive is probably seeking
+	 * or something.  Snooze for a couple msecs, then
+	 * chk-status again.  If still busy, queue delayed work.
+	 */
+	status = ata_busy_wait(ap, ATA_BUSY, 5);
+	if (status & ATA_BUSY) {
+		msleep(2);
+		status = ata_busy_wait(ap, ATA_BUSY, 10);
+		if (status & ATA_BUSY) {
+			ata_port_queue_task(ap, ata_pio_task, qc, ATA_SHORT_PAUSE);
+			return;
+		}
+	}
+
+	/* move the HSM */
+	poll_next = ata_hsm_move(ap, qc, status, 1);
+
+	/* another command or interrupt handler
+	 * may be running at this point.
+	 */
+	if (poll_next)
+		goto fsm_start;
+}
+
+/**
+ *	ata_qc_new - Request an available ATA command, for queueing
+ *	@ap: Port associated with device @dev
+ *	@dev: Device from whom we request an available command structure
+ *
+ *	LOCKING:
+ *	None.
+ */
+
+static struct ata_queued_cmd *ata_qc_new(struct ata_port *ap)
+{
+	struct ata_queued_cmd *qc = NULL;
+	unsigned int i;
+
+	/* no command while frozen */
+	if (unlikely(ap->pflags & ATA_PFLAG_FROZEN))
+		return NULL;
+
+	/* the last tag is reserved for internal command. */
+	for (i = 0; i < ATA_MAX_QUEUE - 1; i++)
+		if (!test_and_set_bit(i, &ap->qc_allocated)) {
+			qc = __ata_qc_from_tag(ap, i);
+			break;
+		}
+
+	if (qc)
+		qc->tag = i;
+
+	return qc;
+}
+
+/**
+ *	ata_qc_new_init - Request an available ATA command, and initialize it
+ *	@dev: Device from whom we request an available command structure
+ *
+ *	LOCKING:
+ *	None.
+ */
+
+struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev)
+{
+	struct ata_port *ap = dev->ap;
+	struct ata_queued_cmd *qc;
+
+	qc = ata_qc_new(ap);
+	if (qc) {
+		qc->scsicmd = NULL;
+		qc->ap = ap;
+		qc->dev = dev;
+
+		ata_qc_reinit(qc);
+	}
+
+	return qc;
+}
+
+/**
+ *	ata_qc_free - free unused ata_queued_cmd
+ *	@qc: Command to complete
+ *
+ *	Designed to free unused ata_queued_cmd object
+ *	in case something prevents using it.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ */
+void ata_qc_free(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+	unsigned int tag;
+
+	WARN_ON(qc == NULL);	/* ata_qc_from_tag _might_ return NULL */
+
+	qc->flags = 0;
+	tag = qc->tag;
+	if (likely(ata_tag_valid(tag))) {
+		qc->tag = ATA_TAG_POISON;
+		clear_bit(tag, &ap->qc_allocated);
+	}
+}
+
+void __ata_qc_complete(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+
+	WARN_ON(qc == NULL);	/* ata_qc_from_tag _might_ return NULL */
+	WARN_ON(!(qc->flags & ATA_QCFLAG_ACTIVE));
+
+	if (likely(qc->flags & ATA_QCFLAG_DMAMAP))
+		ata_sg_clean(qc);
+
+	/* command should be marked inactive atomically with qc completion */
+	if (qc->tf.protocol == ATA_PROT_NCQ)
+		ap->sactive &= ~(1 << qc->tag);
+	else
+		ap->active_tag = ATA_TAG_POISON;
+
+	/* atapi: mark qc as inactive to prevent the interrupt handler
+	 * from completing the command twice later, before the error handler
+	 * is called. (when rc != 0 and atapi request sense is needed)
+	 */
+	qc->flags &= ~ATA_QCFLAG_ACTIVE;
+	ap->qc_active &= ~(1 << qc->tag);
+
+	/* call completion callback */
+	qc->complete_fn(qc);
+}
+
+/**
+ *	ata_qc_complete - Complete an active ATA command
+ *	@qc: Command to complete
+ *	@err_mask: ATA Status register contents
+ *
+ *	Indicate to the mid and upper layers that an ATA
+ *	command has completed, with either an ok or not-ok status.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ */
+void ata_qc_complete(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+
+	/* XXX: New EH and old EH use different mechanisms to
+	 * synchronize EH with regular execution path.
+	 *
+	 * In new EH, a failed qc is marked with ATA_QCFLAG_FAILED.
+	 * Normal execution path is responsible for not accessing a
+	 * failed qc.  libata core enforces the rule by returning NULL
+	 * from ata_qc_from_tag() for failed qcs.
+	 *
+	 * Old EH depends on ata_qc_complete() nullifying completion
+	 * requests if ATA_QCFLAG_EH_SCHEDULED is set.  Old EH does
+	 * not synchronize with interrupt handler.  Only PIO task is
+	 * taken care of.
+	 */
+	if (ap->ops->error_handler) {
+		WARN_ON(ap->pflags & ATA_PFLAG_FROZEN);
+
+		if (unlikely(qc->err_mask))
+			qc->flags |= ATA_QCFLAG_FAILED;
+
+		if (unlikely(qc->flags & ATA_QCFLAG_FAILED)) {
+			if (!ata_tag_internal(qc->tag)) {
+				/* always fill result TF for failed qc */
+				ap->ops->tf_read(ap, &qc->result_tf);
+				ata_qc_schedule_eh(qc);
+				return;
+			}
+		}
+
+		/* read result TF if requested */
+		if (qc->flags & ATA_QCFLAG_RESULT_TF)
+			ap->ops->tf_read(ap, &qc->result_tf);
+
+		__ata_qc_complete(qc);
+	} else {
+		if (qc->flags & ATA_QCFLAG_EH_SCHEDULED)
+			return;
+
+		/* read result TF if failed or requested */
+		if (qc->err_mask || qc->flags & ATA_QCFLAG_RESULT_TF)
+			ap->ops->tf_read(ap, &qc->result_tf);
+
+		__ata_qc_complete(qc);
+	}
+}
+
+/**
+ *	ata_qc_complete_multiple - Complete multiple qcs successfully
+ *	@ap: port in question
+ *	@qc_active: new qc_active mask
+ *	@finish_qc: LLDD callback invoked before completing a qc
+ *
+ *	Complete in-flight commands.  This functions is meant to be
+ *	called from low-level driver's interrupt routine to complete
+ *	requests normally.  ap->qc_active and @qc_active is compared
+ *	and commands are completed accordingly.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ *
+ *	RETURNS:
+ *	Number of completed commands on success, -errno otherwise.
+ */
+int ata_qc_complete_multiple(struct ata_port *ap, u32 qc_active,
+			     void (*finish_qc)(struct ata_queued_cmd *))
+{
+	int nr_done = 0;
+	u32 done_mask;
+	int i;
+
+	done_mask = ap->qc_active ^ qc_active;
+
+	if (unlikely(done_mask & qc_active)) {
+		ata_port_printk(ap, KERN_ERR, "illegal qc_active transition "
+				"(%08x->%08x)\n", ap->qc_active, qc_active);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < ATA_MAX_QUEUE; i++) {
+		struct ata_queued_cmd *qc;
+
+		if (!(done_mask & (1 << i)))
+			continue;
+
+		if ((qc = ata_qc_from_tag(ap, i))) {
+			if (finish_qc)
+				finish_qc(qc);
+			ata_qc_complete(qc);
+			nr_done++;
+		}
+	}
+
+	return nr_done;
+}
+
+static inline int ata_should_dma_map(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+
+	switch (qc->tf.protocol) {
+	case ATA_PROT_NCQ:
+	case ATA_PROT_DMA:
+	case ATA_PROT_ATAPI_DMA:
+		return 1;
+
+	case ATA_PROT_ATAPI:
+	case ATA_PROT_PIO:
+		if (ap->flags & ATA_FLAG_PIO_DMA)
+			return 1;
+
+		/* fall through */
+
+	default:
+		return 0;
+	}
+
+	/* never reached */
+}
+
+/**
+ *	ata_qc_issue - issue taskfile to device
+ *	@qc: command to issue to device
+ *
+ *	Prepare an ATA command to submission to device.
+ *	This includes mapping the data into a DMA-able
+ *	area, filling in the S/G table, and finally
+ *	writing the taskfile to hardware, starting the command.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ */
+void ata_qc_issue(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+
+	/* Make sure only one non-NCQ command is outstanding.  The
+	 * check is skipped for old EH because it reuses active qc to
+	 * request ATAPI sense.
+	 */
+	WARN_ON(ap->ops->error_handler && ata_tag_valid(ap->active_tag));
+
+	if (qc->tf.protocol == ATA_PROT_NCQ) {
+		WARN_ON(ap->sactive & (1 << qc->tag));
+		ap->sactive |= 1 << qc->tag;
+	} else {
+		WARN_ON(ap->sactive);
+		ap->active_tag = qc->tag;
+	}
+
+	qc->flags |= ATA_QCFLAG_ACTIVE;
+	ap->qc_active |= 1 << qc->tag;
+
+	if (ata_should_dma_map(qc)) {
+		if (qc->flags & ATA_QCFLAG_SG) {
+			if (ata_sg_setup(qc))
+				goto sg_err;
+		} else if (qc->flags & ATA_QCFLAG_SINGLE) {
+			if (ata_sg_setup_one(qc))
+				goto sg_err;
+		}
+	} else {
+		qc->flags &= ~ATA_QCFLAG_DMAMAP;
+	}
+
+	ap->ops->qc_prep(qc);
+
+	qc->err_mask |= ap->ops->qc_issue(qc);
+	if (unlikely(qc->err_mask))
+		goto err;
+	return;
+
+sg_err:
+	qc->flags &= ~ATA_QCFLAG_DMAMAP;
+	qc->err_mask |= AC_ERR_SYSTEM;
+err:
+	ata_qc_complete(qc);
+}
+
+/**
+ *	ata_qc_issue_prot - issue taskfile to device in proto-dependent manner
+ *	@qc: command to issue to device
+ *
+ *	Using various libata functions and hooks, this function
+ *	starts an ATA command.  ATA commands are grouped into
+ *	classes called "protocols", and issuing each type of protocol
+ *	is slightly different.
+ *
+ *	May be used as the qc_issue() entry in ata_port_operations.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ *
+ *	RETURNS:
+ *	Zero on success, AC_ERR_* mask on failure
+ */
+
+unsigned int ata_qc_issue_prot(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+
+	/* Use polling pio if the LLD doesn't handle
+	 * interrupt driven pio and atapi CDB interrupt.
+	 */
+	if (ap->flags & ATA_FLAG_PIO_POLLING) {
+		switch (qc->tf.protocol) {
+		case ATA_PROT_PIO:
+		case ATA_PROT_ATAPI:
+		case ATA_PROT_ATAPI_NODATA:
+			qc->tf.flags |= ATA_TFLAG_POLLING;
+			break;
+		case ATA_PROT_ATAPI_DMA:
+			if (qc->dev->flags & ATA_DFLAG_CDB_INTR)
+				/* see ata_dma_blacklisted() */
+				BUG();
+			break;
+		default:
+			break;
+		}
+	}
+
+	/* select the device */
+	ata_dev_select(ap, qc->dev->devno, 1, 0);
+
+	/* start the command */
+	switch (qc->tf.protocol) {
+	case ATA_PROT_NODATA:
+		if (qc->tf.flags & ATA_TFLAG_POLLING)
+			ata_qc_set_polling(qc);
+
+		ata_tf_to_host(ap, &qc->tf);
+		ap->hsm_task_state = HSM_ST_LAST;
+
+		if (qc->tf.flags & ATA_TFLAG_POLLING)
+			ata_port_queue_task(ap, ata_pio_task, qc, 0);
+
+		break;
+
+	case ATA_PROT_DMA:
+		WARN_ON(qc->tf.flags & ATA_TFLAG_POLLING);
+
+		ap->ops->tf_load(ap, &qc->tf);	 /* load tf registers */
+		ap->ops->bmdma_setup(qc);	    /* set up bmdma */
+		ap->ops->bmdma_start(qc);	    /* initiate bmdma */
+		ap->hsm_task_state = HSM_ST_LAST;
+		break;
+
+	case ATA_PROT_PIO:
+		if (qc->tf.flags & ATA_TFLAG_POLLING)
+			ata_qc_set_polling(qc);
+
+		ata_tf_to_host(ap, &qc->tf);
+
+		if (qc->tf.flags & ATA_TFLAG_WRITE) {
+			/* PIO data out protocol */
+			ap->hsm_task_state = HSM_ST_FIRST;
+			ata_port_queue_task(ap, ata_pio_task, qc, 0);
+
+			/* always send first data block using
+			 * the ata_pio_task() codepath.
+			 */
+		} else {
+			/* PIO data in protocol */
+			ap->hsm_task_state = HSM_ST;
+
+			if (qc->tf.flags & ATA_TFLAG_POLLING)
+				ata_port_queue_task(ap, ata_pio_task, qc, 0);
+
+			/* if polling, ata_pio_task() handles the rest.
+			 * otherwise, interrupt handler takes over from here.
+			 */
+		}
+
+		break;
+
+	case ATA_PROT_ATAPI:
+	case ATA_PROT_ATAPI_NODATA:
+		if (qc->tf.flags & ATA_TFLAG_POLLING)
+			ata_qc_set_polling(qc);
+
+		ata_tf_to_host(ap, &qc->tf);
+
+		ap->hsm_task_state = HSM_ST_FIRST;
+
+		/* send cdb by polling if no cdb interrupt */
+		if ((!(qc->dev->flags & ATA_DFLAG_CDB_INTR)) ||
+		    (qc->tf.flags & ATA_TFLAG_POLLING))
+			ata_port_queue_task(ap, ata_pio_task, qc, 0);
+		break;
+
+	case ATA_PROT_ATAPI_DMA:
+		WARN_ON(qc->tf.flags & ATA_TFLAG_POLLING);
+
+		ap->ops->tf_load(ap, &qc->tf);	 /* load tf registers */
+		ap->ops->bmdma_setup(qc);	    /* set up bmdma */
+		ap->hsm_task_state = HSM_ST_FIRST;
+
+		/* send cdb by polling if no cdb interrupt */
+		if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
+			ata_port_queue_task(ap, ata_pio_task, qc, 0);
+		break;
+
+	default:
+		WARN_ON(1);
+		return AC_ERR_SYSTEM;
+	}
+
+	return 0;
+}
+
+/**
+ *	ata_host_intr - Handle host interrupt for given (port, task)
+ *	@ap: Port on which interrupt arrived (possibly...)
+ *	@qc: Taskfile currently active in engine
+ *
+ *	Handle host interrupt for given queued command.  Currently,
+ *	only DMA interrupts are handled.  All other commands are
+ *	handled via polling with interrupts disabled (nIEN bit).
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ *
+ *	RETURNS:
+ *	One if interrupt was handled, zero if not (shared irq).
+ */
+
+inline unsigned int ata_host_intr (struct ata_port *ap,
+				   struct ata_queued_cmd *qc)
+{
+	u8 status, host_stat = 0;
+
+	VPRINTK("ata%u: protocol %d task_state %d\n",
+		ap->id, qc->tf.protocol, ap->hsm_task_state);
+
+	/* Check whether we are expecting interrupt in this state */
+	switch (ap->hsm_task_state) {
+	case HSM_ST_FIRST:
+		/* Some pre-ATAPI-4 devices assert INTRQ
+		 * at this state when ready to receive CDB.
+		 */
+
+		/* Check the ATA_DFLAG_CDB_INTR flag is enough here.
+		 * The flag was turned on only for atapi devices.
+		 * No need to check is_atapi_taskfile(&qc->tf) again.
+		 */
+		if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
+			goto idle_irq;
+		break;
+	case HSM_ST_LAST:
+		if (qc->tf.protocol == ATA_PROT_DMA ||
+		    qc->tf.protocol == ATA_PROT_ATAPI_DMA) {
+			/* check status of DMA engine */
+			host_stat = ap->ops->bmdma_status(ap);
+			VPRINTK("ata%u: host_stat 0x%X\n", ap->id, host_stat);
+
+			/* if it's not our irq... */
+			if (!(host_stat & ATA_DMA_INTR))
+				goto idle_irq;
+
+			/* before we do anything else, clear DMA-Start bit */
+			ap->ops->bmdma_stop(qc);
+
+			if (unlikely(host_stat & ATA_DMA_ERR)) {
+				/* error when transfering data to/from memory */
+				qc->err_mask |= AC_ERR_HOST_BUS;
+				ap->hsm_task_state = HSM_ST_ERR;
+			}
+		}
+		break;
+	case HSM_ST:
+		break;
+	default:
+		goto idle_irq;
+	}
+
+	/* check altstatus */
+	status = ata_altstatus(ap);
+	if (status & ATA_BUSY)
+		goto idle_irq;
+
+	/* check main status, clearing INTRQ */
+	status = ata_chk_status(ap);
+	if (unlikely(status & ATA_BUSY))
+		goto idle_irq;
+
+	/* ack bmdma irq events */
+	ap->ops->irq_clear(ap);
+
+	ata_hsm_move(ap, qc, status, 0);
+	return 1;	/* irq handled */
+
+idle_irq:
+	ap->stats.idle_irq++;
+
+#ifdef ATA_IRQ_TRAP
+	if ((ap->stats.idle_irq % 1000) == 0) {
+		ata_irq_ack(ap, 0); /* debug trap */
+		ata_port_printk(ap, KERN_WARNING, "irq trap\n");
+		return 1;
+	}
+#endif
+	return 0;	/* irq not handled */
+}
+
+/**
+ *	ata_interrupt - Default ATA host interrupt handler
+ *	@irq: irq line (unused)
+ *	@dev_instance: pointer to our ata_host_set information structure
+ *	@regs: unused
+ *
+ *	Default interrupt handler for PCI IDE devices.  Calls
+ *	ata_host_intr() for each port that is not disabled.
+ *
+ *	LOCKING:
+ *	Obtains host_set lock during operation.
+ *
+ *	RETURNS:
+ *	IRQ_NONE or IRQ_HANDLED.
+ */
+
+irqreturn_t ata_interrupt (int irq, void *dev_instance, struct pt_regs *regs)
+{
+	struct ata_host_set *host_set = dev_instance;
+	unsigned int i;
+	unsigned int handled = 0;
+	unsigned long flags;
+
+	/* TODO: make _irqsave conditional on x86 PCI IDE legacy mode */
+	spin_lock_irqsave(&host_set->lock, flags);
+
+	for (i = 0; i < host_set->n_ports; i++) {
+		struct ata_port *ap;
+
+		ap = host_set->ports[i];
+		if (ap &&
+		    !(ap->flags & ATA_FLAG_DISABLED)) {
+			struct ata_queued_cmd *qc;
+
+			qc = ata_qc_from_tag(ap, ap->active_tag);
+			if (qc && (!(qc->tf.flags & ATA_TFLAG_POLLING)) &&
+			    (qc->flags & ATA_QCFLAG_ACTIVE))
+				handled |= ata_host_intr(ap, qc);
+		}
+	}
+
+	spin_unlock_irqrestore(&host_set->lock, flags);
+
+	return IRQ_RETVAL(handled);
+}
+
+/**
+ *	sata_scr_valid - test whether SCRs are accessible
+ *	@ap: ATA port to test SCR accessibility for
+ *
+ *	Test whether SCRs are accessible for @ap.
+ *
+ *	LOCKING:
+ *	None.
+ *
+ *	RETURNS:
+ *	1 if SCRs are accessible, 0 otherwise.
+ */
+int sata_scr_valid(struct ata_port *ap)
+{
+	return ap->cbl == ATA_CBL_SATA && ap->ops->scr_read;
+}
+
+/**
+ *	sata_scr_read - read SCR register of the specified port
+ *	@ap: ATA port to read SCR for
+ *	@reg: SCR to read
+ *	@val: Place to store read value
+ *
+ *	Read SCR register @reg of @ap into *@val.  This function is
+ *	guaranteed to succeed if the cable type of the port is SATA
+ *	and the port implements ->scr_read.
+ *
+ *	LOCKING:
+ *	None.
+ *
+ *	RETURNS:
+ *	0 on success, negative errno on failure.
+ */
+int sata_scr_read(struct ata_port *ap, int reg, u32 *val)
+{
+	if (sata_scr_valid(ap)) {
+		*val = ap->ops->scr_read(ap, reg);
+		return 0;
+	}
+	return -EOPNOTSUPP;
+}
+
+/**
+ *	sata_scr_write - write SCR register of the specified port
+ *	@ap: ATA port to write SCR for
+ *	@reg: SCR to write
+ *	@val: value to write
+ *
+ *	Write @val to SCR register @reg of @ap.  This function is
+ *	guaranteed to succeed if the cable type of the port is SATA
+ *	and the port implements ->scr_read.
+ *
+ *	LOCKING:
+ *	None.
+ *
+ *	RETURNS:
+ *	0 on success, negative errno on failure.
+ */
+int sata_scr_write(struct ata_port *ap, int reg, u32 val)
+{
+	if (sata_scr_valid(ap)) {
+		ap->ops->scr_write(ap, reg, val);
+		return 0;
+	}
+	return -EOPNOTSUPP;
+}
+
+/**
+ *	sata_scr_write_flush - write SCR register of the specified port and flush
+ *	@ap: ATA port to write SCR for
+ *	@reg: SCR to write
+ *	@val: value to write
+ *
+ *	This function is identical to sata_scr_write() except that this
+ *	function performs flush after writing to the register.
+ *
+ *	LOCKING:
+ *	None.
+ *
+ *	RETURNS:
+ *	0 on success, negative errno on failure.
+ */
+int sata_scr_write_flush(struct ata_port *ap, int reg, u32 val)
+{
+	if (sata_scr_valid(ap)) {
+		ap->ops->scr_write(ap, reg, val);
+		ap->ops->scr_read(ap, reg);
+		return 0;
+	}
+	return -EOPNOTSUPP;
+}
+
+/**
+ *	ata_port_online - test whether the given port is online
+ *	@ap: ATA port to test
+ *
+ *	Test whether @ap is online.  Note that this function returns 0
+ *	if online status of @ap cannot be obtained, so
+ *	ata_port_online(ap) != !ata_port_offline(ap).
+ *
+ *	LOCKING:
+ *	None.
+ *
+ *	RETURNS:
+ *	1 if the port online status is available and online.
+ */
+int ata_port_online(struct ata_port *ap)
+{
+	u32 sstatus;
+
+	if (!sata_scr_read(ap, SCR_STATUS, &sstatus) && (sstatus & 0xf) == 0x3)
+		return 1;
+	return 0;
+}
+
+/**
+ *	ata_port_offline - test whether the given port is offline
+ *	@ap: ATA port to test
+ *
+ *	Test whether @ap is offline.  Note that this function returns
+ *	0 if offline status of @ap cannot be obtained, so
+ *	ata_port_online(ap) != !ata_port_offline(ap).
+ *
+ *	LOCKING:
+ *	None.
+ *
+ *	RETURNS:
+ *	1 if the port offline status is available and offline.
+ */
+int ata_port_offline(struct ata_port *ap)
+{
+	u32 sstatus;
+
+	if (!sata_scr_read(ap, SCR_STATUS, &sstatus) && (sstatus & 0xf) != 0x3)
+		return 1;
+	return 0;
+}
+
+int ata_flush_cache(struct ata_device *dev)
+{
+	unsigned int err_mask;
+	u8 cmd;
+
+	if (!ata_try_flush_cache(dev))
+		return 0;
+
+	if (ata_id_has_flush_ext(dev->id))
+		cmd = ATA_CMD_FLUSH_EXT;
+	else
+		cmd = ATA_CMD_FLUSH;
+
+	err_mask = ata_do_simple_cmd(dev, cmd);
+	if (err_mask) {
+		ata_dev_printk(dev, KERN_ERR, "failed to flush cache\n");
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int ata_host_set_request_pm(struct ata_host_set *host_set,
+				   pm_message_t mesg, unsigned int action,
+				   unsigned int ehi_flags, int wait)
+{
+	unsigned long flags;
+	int i, rc;
+
+	for (i = 0; i < host_set->n_ports; i++) {
+		struct ata_port *ap = host_set->ports[i];
+
+		/* Previous resume operation might still be in
+		 * progress.  Wait for PM_PENDING to clear.
+		 */
+		if (ap->pflags & ATA_PFLAG_PM_PENDING) {
+			ata_port_wait_eh(ap);
+			WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
+		}
+
+		/* request PM ops to EH */
+		spin_lock_irqsave(ap->lock, flags);
+
+		ap->pm_mesg = mesg;
+		if (wait) {
+			rc = 0;
+			ap->pm_result = &rc;
+		}
+
+		ap->pflags |= ATA_PFLAG_PM_PENDING;
+		ap->eh_info.action |= action;
+		ap->eh_info.flags |= ehi_flags;
+
+		ata_port_schedule_eh(ap);
+
+		spin_unlock_irqrestore(ap->lock, flags);
+
+		/* wait and check result */
+		if (wait) {
+			ata_port_wait_eh(ap);
+			WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
+			if (rc)
+				return rc;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ *	ata_host_set_suspend - suspend host_set
+ *	@host_set: host_set to suspend
+ *	@mesg: PM message
+ *
+ *	Suspend @host_set.  Actual operation is performed by EH.  This
+ *	function requests EH to perform PM operations and waits for EH
+ *	to finish.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep).
+ *
+ *	RETURNS:
+ *	0 on success, -errno on failure.
+ */
+int ata_host_set_suspend(struct ata_host_set *host_set, pm_message_t mesg)
+{
+	int i, j, rc;
+
+	rc = ata_host_set_request_pm(host_set, mesg, 0, ATA_EHI_QUIET, 1);
+	if (rc)
+		goto fail;
+
+	/* EH is quiescent now.  Fail if we have any ready device.
+	 * This happens if hotplug occurs between completion of device
+	 * suspension and here.
+	 */
+	for (i = 0; i < host_set->n_ports; i++) {
+		struct ata_port *ap = host_set->ports[i];
+
+		for (j = 0; j < ATA_MAX_DEVICES; j++) {
+			struct ata_device *dev = &ap->device[j];
+
+			if (ata_dev_ready(dev)) {
+				ata_port_printk(ap, KERN_WARNING,
+						"suspend failed, device %d "
+						"still active\n", dev->devno);
+				rc = -EBUSY;
+				goto fail;
+			}
+		}
+	}
+
+	host_set->dev->power.power_state = mesg;
+	return 0;
+
+ fail:
+	ata_host_set_resume(host_set);
+	return rc;
+}
+
+/**
+ *	ata_host_set_resume - resume host_set
+ *	@host_set: host_set to resume
+ *
+ *	Resume @host_set.  Actual operation is performed by EH.  This
+ *	function requests EH to perform PM operations and returns.
+ *	Note that all resume operations are performed parallely.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep).
+ */
+void ata_host_set_resume(struct ata_host_set *host_set)
+{
+	ata_host_set_request_pm(host_set, PMSG_ON, ATA_EH_SOFTRESET,
+				ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 0);
+	host_set->dev->power.power_state = PMSG_ON;
+}
+
+/**
+ *	ata_port_start - Set port up for dma.
+ *	@ap: Port to initialize
+ *
+ *	Called just after data structures for each port are
+ *	initialized.  Allocates space for PRD table.
+ *
+ *	May be used as the port_start() entry in ata_port_operations.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ */
+
+int ata_port_start (struct ata_port *ap)
+{
+	struct device *dev = ap->dev;
+	int rc;
+
+	ap->prd = dma_alloc_coherent(dev, ATA_PRD_TBL_SZ, &ap->prd_dma, GFP_KERNEL);
+	if (!ap->prd)
+		return -ENOMEM;
+
+	rc = ata_pad_alloc(ap, dev);
+	if (rc) {
+		dma_free_coherent(dev, ATA_PRD_TBL_SZ, ap->prd, ap->prd_dma);
+		return rc;
+	}
+
+	DPRINTK("prd alloc, virt %p, dma %llx\n", ap->prd, (unsigned long long) ap->prd_dma);
+
+	return 0;
+}
+
+
+/**
+ *	ata_port_stop - Undo ata_port_start()
+ *	@ap: Port to shut down
+ *
+ *	Frees the PRD table.
+ *
+ *	May be used as the port_stop() entry in ata_port_operations.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ */
+
+void ata_port_stop (struct ata_port *ap)
+{
+	struct device *dev = ap->dev;
+
+	dma_free_coherent(dev, ATA_PRD_TBL_SZ, ap->prd, ap->prd_dma);
+	ata_pad_free(ap, dev);
+}
+
+void ata_host_stop (struct ata_host_set *host_set)
+{
+	if (host_set->mmio_base)
+		iounmap(host_set->mmio_base);
+}
+
+/**
+ *	ata_dev_init - Initialize an ata_device structure
+ *	@dev: Device structure to initialize
+ *
+ *	Initialize @dev in preparation for probing.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ */
+void ata_dev_init(struct ata_device *dev)
+{
+	struct ata_port *ap = dev->ap;
+	unsigned long flags;
+
+	/* SATA spd limit is bound to the first device */
+	ap->sata_spd_limit = ap->hw_sata_spd_limit;
+
+	/* High bits of dev->flags are used to record warm plug
+	 * requests which occur asynchronously.  Synchronize using
+	 * host_set lock.
+	 */
+	spin_lock_irqsave(ap->lock, flags);
+	dev->flags &= ~ATA_DFLAG_INIT_MASK;
+	spin_unlock_irqrestore(ap->lock, flags);
+
+	memset((void *)dev + ATA_DEVICE_CLEAR_OFFSET, 0,
+	       sizeof(*dev) - ATA_DEVICE_CLEAR_OFFSET);
+	dev->pio_mask = UINT_MAX;
+	dev->mwdma_mask = UINT_MAX;
+	dev->udma_mask = UINT_MAX;
+}
+
+/**
+ *	ata_port_init - Initialize an ata_port structure
+ *	@ap: Structure to initialize
+ *	@host_set: Collection of hosts to which @ap belongs
+ *	@ent: Probe information provided by low-level driver
+ *	@port_no: Port number associated with this ata_port
+ *
+ *	Initialize a new ata_port structure.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ */
+void ata_port_init(struct ata_port *ap, struct ata_host_set *host_set,
+		   const struct ata_probe_ent *ent, unsigned int port_no)
+{
+	unsigned int i;
+
+	ap->lock = &host_set->lock;
+	ap->flags = ATA_FLAG_DISABLED;
+	ap->id = ata_unique_id++;
+	ap->ctl = ATA_DEVCTL_OBS;
+	ap->host_set = host_set;
+	ap->dev = ent->dev;
+	ap->port_no = port_no;
+	ap->pio_mask = ent->pio_mask;
+	ap->mwdma_mask = ent->mwdma_mask;
+	ap->udma_mask = ent->udma_mask;
+	ap->flags |= ent->host_flags;
+	ap->ops = ent->port_ops;
+	ap->hw_sata_spd_limit = UINT_MAX;
+	ap->active_tag = ATA_TAG_POISON;
+	ap->last_ctl = 0xFF;
+
+#if defined(ATA_VERBOSE_DEBUG)
+	/* turn on all debugging levels */
+	ap->msg_enable = 0x00FF;
+#elif defined(ATA_DEBUG)
+	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_INFO | ATA_MSG_CTL | ATA_MSG_WARN | ATA_MSG_ERR;
+#else
+	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_ERR | ATA_MSG_WARN;
+#endif
+
+	INIT_WORK(&ap->port_task, NULL, NULL);
+	INIT_WORK(&ap->hotplug_task, ata_scsi_hotplug, ap);
+	INIT_WORK(&ap->scsi_rescan_task, ata_scsi_dev_rescan, ap);
+	INIT_LIST_HEAD(&ap->eh_done_q);
+	init_waitqueue_head(&ap->eh_wait_q);
+
+	/* set cable type */
+	ap->cbl = ATA_CBL_NONE;
+	if (ap->flags & ATA_FLAG_SATA)
+		ap->cbl = ATA_CBL_SATA;
+
+	for (i = 0; i < ATA_MAX_DEVICES; i++) {
+		struct ata_device *dev = &ap->device[i];
+		dev->ap = ap;
+		dev->devno = i;
+		ata_dev_init(dev);
+	}
+
+#ifdef ATA_IRQ_TRAP
+	ap->stats.unhandled_irq = 1;
+	ap->stats.idle_irq = 1;
+#endif
+
+	memcpy(&ap->ioaddr, &ent->port[port_no], sizeof(struct ata_ioports));
+}
+
+/**
+ *	ata_port_init_shost - Initialize SCSI host associated with ATA port
+ *	@ap: ATA port to initialize SCSI host for
+ *	@shost: SCSI host associated with @ap
+ *
+ *	Initialize SCSI host @shost associated with ATA port @ap.
+ *
+ *	LOCKING:
+ *	Inherited from caller.
+ */
+static void ata_port_init_shost(struct ata_port *ap, struct Scsi_Host *shost)
+{
+	ap->host = shost;
+
+	shost->unique_id = ap->id;
+	shost->max_id = 16;
+	shost->max_lun = 1;
+	shost->max_channel = 1;
+	shost->max_cmd_len = 12;
+}
+
+/**
+ *	ata_port_add - Attach low-level ATA driver to system
+ *	@ent: Information provided by low-level driver
+ *	@host_set: Collections of ports to which we add
+ *	@port_no: Port number associated with this host
+ *
+ *	Attach low-level ATA driver to system.
+ *
+ *	LOCKING:
+ *	PCI/etc. bus probe sem.
+ *
+ *	RETURNS:
+ *	New ata_port on success, for NULL on error.
+ */
+static struct ata_port * ata_port_add(const struct ata_probe_ent *ent,
+				      struct ata_host_set *host_set,
+				      unsigned int port_no)
+{
+	struct Scsi_Host *shost;
+	struct ata_port *ap;
+
+	DPRINTK("ENTER\n");
+
+	if (!ent->port_ops->error_handler &&
+	    !(ent->host_flags & (ATA_FLAG_SATA_RESET | ATA_FLAG_SRST))) {
+		printk(KERN_ERR "ata%u: no reset mechanism available\n",
+		       port_no);
+		return NULL;
+	}
+
+	shost = scsi_host_alloc(ent->sht, sizeof(struct ata_port));
+	if (!shost)
+		return NULL;
+
+	shost->transportt = &ata_scsi_transport_template;
+
+	ap = ata_shost_to_port(shost);
+
+	ata_port_init(ap, host_set, ent, port_no);
+	ata_port_init_shost(ap, shost);
+
+	return ap;
+}
+
+/**
+ *	ata_sas_host_init - Initialize a host_set struct
+ *	@host_set:	host_set to initialize
+ *	@dev:		device host_set is attached to
+ *	@flags:	host_set flags
+ *	@ops:		port_ops
+ *
+ *	LOCKING:
+ *	PCI/etc. bus probe sem.
+ *
+ */
+
+void ata_host_set_init(struct ata_host_set *host_set,
+		       struct device *dev, unsigned long flags,
+		       const struct ata_port_operations *ops)
+{
+	spin_lock_init(&host_set->lock);
+	host_set->dev = dev;
+	host_set->flags = flags;
+	host_set->ops = ops;
+}
+
+/**
+ *	ata_device_add - Register hardware device with ATA and SCSI layers
+ *	@ent: Probe information describing hardware device to be registered
+ *
+ *	This function processes the information provided in the probe
+ *	information struct @ent, allocates the necessary ATA and SCSI
+ *	host information structures, initializes them, and registers
+ *	everything with requisite kernel subsystems.
+ *
+ *	This function requests irqs, probes the ATA bus, and probes
+ *	the SCSI bus.
+ *
+ *	LOCKING:
+ *	PCI/etc. bus probe sem.
+ *
+ *	RETURNS:
+ *	Number of ports registered.  Zero on error (no ports registered).
+ */
+int ata_device_add(const struct ata_probe_ent *ent)
+{
+	unsigned int i;
+	struct device *dev = ent->dev;
+	struct ata_host_set *host_set;
+	int rc;
+
+	DPRINTK("ENTER\n");
+	/* alloc a container for our list of ATA ports (buses) */
+	host_set = kzalloc(sizeof(struct ata_host_set) +
+			   (ent->n_ports * sizeof(void *)), GFP_KERNEL);
+	if (!host_set)
+		return 0;
+
+	ata_host_set_init(host_set, dev, ent->host_set_flags, ent->port_ops);
+	host_set->n_ports = ent->n_ports;
+	host_set->irq = ent->irq;
+	host_set->irq2 = ent->irq2;
+	host_set->mmio_base = ent->mmio_base;
+	host_set->private_data = ent->private_data;
+
+	/* register each port bound to this device */
+	for (i = 0; i < host_set->n_ports; i++) {
+		struct ata_port *ap;
+		unsigned long xfer_mode_mask;
+		int irq_line = ent->irq;
+
+		ap = ata_port_add(ent, host_set, i);
+		if (!ap)
+			goto err_out;
+
+		host_set->ports[i] = ap;
+
+		/* dummy? */
+		if (ent->dummy_port_mask & (1 << i)) {
+			ata_port_printk(ap, KERN_INFO, "DUMMY\n");
+			ap->ops = &ata_dummy_port_ops;
+			continue;
+		}
+
+		/* start port */
+		rc = ap->ops->port_start(ap);
+		if (rc) {
+			host_set->ports[i] = NULL;
+			scsi_host_put(ap->host);
+			goto err_out;
+		}
+
+		/* Report the secondary IRQ for second channel legacy */
+		if (i == 1 && ent->irq2)
+			irq_line = ent->irq2;
+
+		xfer_mode_mask =(ap->udma_mask << ATA_SHIFT_UDMA) |
+				(ap->mwdma_mask << ATA_SHIFT_MWDMA) |
+				(ap->pio_mask << ATA_SHIFT_PIO);
+
+		/* print per-port info to dmesg */
+		ata_port_printk(ap, KERN_INFO, "%cATA max %s cmd 0x%lX "
+				"ctl 0x%lX bmdma 0x%lX irq %d\n",
+				ap->flags & ATA_FLAG_SATA ? 'S' : 'P',
+				ata_mode_string(xfer_mode_mask),
+				ap->ioaddr.cmd_addr,
+				ap->ioaddr.ctl_addr,
+				ap->ioaddr.bmdma_addr,
+				irq_line);
+
+		ata_chk_status(ap);
+		host_set->ops->irq_clear(ap);
+		ata_eh_freeze_port(ap);	/* freeze port before requesting IRQ */
+	}
+
+	/* obtain irq, that may be shared between channels */
+	rc = request_irq(ent->irq, ent->port_ops->irq_handler, ent->irq_flags,
+			 DRV_NAME, host_set);
+	if (rc) {
+		dev_printk(KERN_ERR, dev, "irq %lu request failed: %d\n",
+			   ent->irq, rc);
+		goto err_out;
+	}
+
+	/* do we have a second IRQ for the other channel, eg legacy mode */
+	if (ent->irq2) {
+		/* We will get weird core code crashes later if this is true
+		   so trap it now */
+		BUG_ON(ent->irq == ent->irq2);
+
+		rc = request_irq(ent->irq2, ent->port_ops->irq_handler, ent->irq_flags,
+			 DRV_NAME, host_set);
+		if (rc) {
+			dev_printk(KERN_ERR, dev, "irq %lu request failed: %d\n",
+				   ent->irq2, rc);
+			goto err_out_free_irq;
+		}
+	}
+
+	/* perform each probe synchronously */
+	DPRINTK("probe begin\n");
+	for (i = 0; i < host_set->n_ports; i++) {
+		struct ata_port *ap = host_set->ports[i];
+		u32 scontrol;
+		int rc;
+
+		/* init sata_spd_limit to the current value */
+		if (sata_scr_read(ap, SCR_CONTROL, &scontrol) == 0) {
+			int spd = (scontrol >> 4) & 0xf;
+			ap->hw_sata_spd_limit &= (1 << spd) - 1;
+		}
+		ap->sata_spd_limit = ap->hw_sata_spd_limit;
+
+		rc = scsi_add_host(ap->host, dev);
+		if (rc) {
+			ata_port_printk(ap, KERN_ERR, "scsi_add_host failed\n");
+			/* FIXME: do something useful here */
+			/* FIXME: handle unconditional calls to
+			 * scsi_scan_host and ata_host_remove, below,
+			 * at the very least
+			 */
+		}
+
+		if (ap->ops->error_handler) {
+			struct ata_eh_info *ehi = &ap->eh_info;
+			unsigned long flags;
+
+			ata_port_probe(ap);
+
+			/* kick EH for boot probing */
+			spin_lock_irqsave(ap->lock, flags);
+
+			ehi->probe_mask = (1 << ATA_MAX_DEVICES) - 1;
+			ehi->action |= ATA_EH_SOFTRESET;
+			ehi->flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET;
+
+			ap->pflags |= ATA_PFLAG_LOADING;
+			ata_port_schedule_eh(ap);
+
+			spin_unlock_irqrestore(ap->lock, flags);
+
+			/* wait for EH to finish */
+			ata_port_wait_eh(ap);
+		} else {
+			DPRINTK("ata%u: bus probe begin\n", ap->id);
+			rc = ata_bus_probe(ap);
+			DPRINTK("ata%u: bus probe end\n", ap->id);
+
+			if (rc) {
+				/* FIXME: do something useful here?
+				 * Current libata behavior will
+				 * tear down everything when
+				 * the module is removed
+				 * or the h/w is unplugged.
+				 */
+			}
+		}
+	}
+
+	/* probes are done, now scan each port's disk(s) */
+	DPRINTK("host probe begin\n");
+	for (i = 0; i < host_set->n_ports; i++) {
+		struct ata_port *ap = host_set->ports[i];
+
+		ata_scsi_scan_host(ap);
+	}
+
+	dev_set_drvdata(dev, host_set);
+
+	VPRINTK("EXIT, returning %u\n", ent->n_ports);
+	return ent->n_ports; /* success */
+
+err_out_free_irq:
+	free_irq(ent->irq, host_set);
+err_out:
+	for (i = 0; i < host_set->n_ports; i++) {
+		struct ata_port *ap = host_set->ports[i];
+		if (ap) {
+			ap->ops->port_stop(ap);
+			scsi_host_put(ap->host);
+		}
+	}
+
+	kfree(host_set);
+	VPRINTK("EXIT, returning 0\n");
+	return 0;
+}
+
+/**
+ *	ata_port_detach - Detach ATA port in prepration of device removal
+ *	@ap: ATA port to be detached
+ *
+ *	Detach all ATA devices and the associated SCSI devices of @ap;
+ *	then, remove the associated SCSI host.  @ap is guaranteed to
+ *	be quiescent on return from this function.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep).
+ */
+void ata_port_detach(struct ata_port *ap)
+{
+	unsigned long flags;
+	int i;
+
+	if (!ap->ops->error_handler)
+		goto skip_eh;
+
+	/* tell EH we're leaving & flush EH */
+	spin_lock_irqsave(ap->lock, flags);
+	ap->pflags |= ATA_PFLAG_UNLOADING;
+	spin_unlock_irqrestore(ap->lock, flags);
+
+	ata_port_wait_eh(ap);
+
+	/* EH is now guaranteed to see UNLOADING, so no new device
+	 * will be attached.  Disable all existing devices.
+	 */
+	spin_lock_irqsave(ap->lock, flags);
+
+	for (i = 0; i < ATA_MAX_DEVICES; i++)
+		ata_dev_disable(&ap->device[i]);
+
+	spin_unlock_irqrestore(ap->lock, flags);
+
+	/* Final freeze & EH.  All in-flight commands are aborted.  EH
+	 * will be skipped and retrials will be terminated with bad
+	 * target.
+	 */
+	spin_lock_irqsave(ap->lock, flags);
+	ata_port_freeze(ap);	/* won't be thawed */
+	spin_unlock_irqrestore(ap->lock, flags);
+
+	ata_port_wait_eh(ap);
+
+	/* Flush hotplug task.  The sequence is similar to
+	 * ata_port_flush_task().
+	 */
+	flush_workqueue(ata_aux_wq);
+	cancel_delayed_work(&ap->hotplug_task);
+	flush_workqueue(ata_aux_wq);
+
+ skip_eh:
+	/* remove the associated SCSI host */
+	scsi_remove_host(ap->host);
+}
+
+/**
+ *	ata_host_set_remove - PCI layer callback for device removal
+ *	@host_set: ATA host set that was removed
+ *
+ *	Unregister all objects associated with this host set. Free those
+ *	objects.
+ *
+ *	LOCKING:
+ *	Inherited from calling layer (may sleep).
+ */
+
+void ata_host_set_remove(struct ata_host_set *host_set)
+{
+	unsigned int i;
+
+	for (i = 0; i < host_set->n_ports; i++)
+		ata_port_detach(host_set->ports[i]);
+
+	free_irq(host_set->irq, host_set);
+	if (host_set->irq2)
+		free_irq(host_set->irq2, host_set);
+
+	for (i = 0; i < host_set->n_ports; i++) {
+		struct ata_port *ap = host_set->ports[i];
+
+		ata_scsi_release(ap->host);
+
+		if ((ap->flags & ATA_FLAG_NO_LEGACY) == 0) {
+			struct ata_ioports *ioaddr = &ap->ioaddr;
+
+			/* FIXME: Add -ac IDE pci mods to remove these special cases */
+			if (ioaddr->cmd_addr == ATA_PRIMARY_CMD)
+				release_region(ATA_PRIMARY_CMD, 8);
+			else if (ioaddr->cmd_addr == ATA_SECONDARY_CMD)
+				release_region(ATA_SECONDARY_CMD, 8);
+		}
+
+		scsi_host_put(ap->host);
+	}
+
+	if (host_set->ops->host_stop)
+		host_set->ops->host_stop(host_set);
+
+	kfree(host_set);
+}
+
+/**
+ *	ata_scsi_release - SCSI layer callback hook for host unload
+ *	@host: libata host to be unloaded
+ *
+ *	Performs all duties necessary to shut down a libata port...
+ *	Kill port kthread, disable port, and release resources.
+ *
+ *	LOCKING:
+ *	Inherited from SCSI layer.
+ *
+ *	RETURNS:
+ *	One.
+ */
+
+int ata_scsi_release(struct Scsi_Host *host)
+{
+	struct ata_port *ap = ata_shost_to_port(host);
+
+	DPRINTK("ENTER\n");
+
+	ap->ops->port_disable(ap);
+	ap->ops->port_stop(ap);
+
+	DPRINTK("EXIT\n");
+	return 1;
+}
+
+struct ata_probe_ent *
+ata_probe_ent_alloc(struct device *dev, const struct ata_port_info *port)
+{
+	struct ata_probe_ent *probe_ent;
+
+	probe_ent = kzalloc(sizeof(*probe_ent), GFP_KERNEL);
+	if (!probe_ent) {
+		printk(KERN_ERR DRV_NAME "(%s): out of memory\n",
+		       kobject_name(&(dev->kobj)));
+		return NULL;
+	}
+
+	INIT_LIST_HEAD(&probe_ent->node);
+	probe_ent->dev = dev;
+
+	probe_ent->sht = port->sht;
+	probe_ent->host_flags = port->host_flags;
+	probe_ent->pio_mask = port->pio_mask;
+	probe_ent->mwdma_mask = port->mwdma_mask;
+	probe_ent->udma_mask = port->udma_mask;
+	probe_ent->port_ops = port->port_ops;
+
+	return probe_ent;
+}
+
+/**
+ *	ata_std_ports - initialize ioaddr with standard port offsets.
+ *	@ioaddr: IO address structure to be initialized
+ *
+ *	Utility function which initializes data_addr, error_addr,
+ *	feature_addr, nsect_addr, lbal_addr, lbam_addr, lbah_addr,
+ *	device_addr, status_addr, and command_addr to standard offsets
+ *	relative to cmd_addr.
+ *
+ *	Does not set ctl_addr, altstatus_addr, bmdma_addr, or scr_addr.
+ */
+
+void ata_std_ports(struct ata_ioports *ioaddr)
+{
+	ioaddr->data_addr = ioaddr->cmd_addr + ATA_REG_DATA;
+	ioaddr->error_addr = ioaddr->cmd_addr + ATA_REG_ERR;
+	ioaddr->feature_addr = ioaddr->cmd_addr + ATA_REG_FEATURE;
+	ioaddr->nsect_addr = ioaddr->cmd_addr + ATA_REG_NSECT;
+	ioaddr->lbal_addr = ioaddr->cmd_addr + ATA_REG_LBAL;
+	ioaddr->lbam_addr = ioaddr->cmd_addr + ATA_REG_LBAM;
+	ioaddr->lbah_addr = ioaddr->cmd_addr + ATA_REG_LBAH;
+	ioaddr->device_addr = ioaddr->cmd_addr + ATA_REG_DEVICE;
+	ioaddr->status_addr = ioaddr->cmd_addr + ATA_REG_STATUS;
+	ioaddr->command_addr = ioaddr->cmd_addr + ATA_REG_CMD;
+}
+
+
+#ifdef CONFIG_PCI
+
+void ata_pci_host_stop (struct ata_host_set *host_set)
+{
+	struct pci_dev *pdev = to_pci_dev(host_set->dev);
+
+	pci_iounmap(pdev, host_set->mmio_base);
+}
+
+/**
+ *	ata_pci_remove_one - PCI layer callback for device removal
+ *	@pdev: PCI device that was removed
+ *
+ *	PCI layer indicates to libata via this hook that
+ *	hot-unplug or module unload event has occurred.
+ *	Handle this by unregistering all objects associated
+ *	with this PCI device.  Free those objects.  Then finally
+ *	release PCI resources and disable device.
+ *
+ *	LOCKING:
+ *	Inherited from PCI layer (may sleep).
+ */
+
+void ata_pci_remove_one (struct pci_dev *pdev)
+{
+	struct device *dev = pci_dev_to_dev(pdev);
+	struct ata_host_set *host_set = dev_get_drvdata(dev);
+
+	ata_host_set_remove(host_set);
+
+	pci_release_regions(pdev);
+	pci_disable_device(pdev);
+	dev_set_drvdata(dev, NULL);
+}
+
+/* move to PCI subsystem */
+int pci_test_config_bits(struct pci_dev *pdev, const struct pci_bits *bits)
+{
+	unsigned long tmp = 0;
+
+	switch (bits->width) {
+	case 1: {
+		u8 tmp8 = 0;
+		pci_read_config_byte(pdev, bits->reg, &tmp8);
+		tmp = tmp8;
+		break;
+	}
+	case 2: {
+		u16 tmp16 = 0;
+		pci_read_config_word(pdev, bits->reg, &tmp16);
+		tmp = tmp16;
+		break;
+	}
+	case 4: {
+		u32 tmp32 = 0;
+		pci_read_config_dword(pdev, bits->reg, &tmp32);
+		tmp = tmp32;
+		break;
+	}
+
+	default:
+		return -EINVAL;
+	}
+
+	tmp &= bits->mask;
+
+	return (tmp == bits->val) ? 1 : 0;
+}
+
+void ata_pci_device_do_suspend(struct pci_dev *pdev, pm_message_t mesg)
+{
+	pci_save_state(pdev);
+
+	if (mesg.event == PM_EVENT_SUSPEND) {
+		pci_disable_device(pdev);
+		pci_set_power_state(pdev, PCI_D3hot);
+	}
+}
+
+void ata_pci_device_do_resume(struct pci_dev *pdev)
+{
+	pci_set_power_state(pdev, PCI_D0);
+	pci_restore_state(pdev);
+	pci_enable_device(pdev);
+	pci_set_master(pdev);
+}
+
+int ata_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg)
+{
+	struct ata_host_set *host_set = dev_get_drvdata(&pdev->dev);
+	int rc = 0;
+
+	rc = ata_host_set_suspend(host_set, mesg);
+	if (rc)
+		return rc;
+
+	ata_pci_device_do_suspend(pdev, mesg);
+
+	return 0;
+}
+
+int ata_pci_device_resume(struct pci_dev *pdev)
+{
+	struct ata_host_set *host_set = dev_get_drvdata(&pdev->dev);
+
+	ata_pci_device_do_resume(pdev);
+	ata_host_set_resume(host_set);
+	return 0;
+}
+#endif /* CONFIG_PCI */
+
+
+static int __init ata_init(void)
+{
+	ata_probe_timeout *= HZ;
+	ata_wq = create_workqueue("ata");
+	if (!ata_wq)
+		return -ENOMEM;
+
+	ata_aux_wq = create_singlethread_workqueue("ata_aux");
+	if (!ata_aux_wq) {
+		destroy_workqueue(ata_wq);
+		return -ENOMEM;
+	}
+
+	printk(KERN_DEBUG "libata version " DRV_VERSION " loaded.\n");
+	return 0;
+}
+
+static void __exit ata_exit(void)
+{
+	destroy_workqueue(ata_wq);
+	destroy_workqueue(ata_aux_wq);
+}
+
+module_init(ata_init);
+module_exit(ata_exit);
+
+static unsigned long ratelimit_time;
+static DEFINE_SPINLOCK(ata_ratelimit_lock);
+
+int ata_ratelimit(void)
+{
+	int rc;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ata_ratelimit_lock, flags);
+
+	if (time_after(jiffies, ratelimit_time)) {
+		rc = 1;
+		ratelimit_time = jiffies + (HZ/5);
+	} else
+		rc = 0;
+
+	spin_unlock_irqrestore(&ata_ratelimit_lock, flags);
+
+	return rc;
+}
+
+/**
+ *	ata_wait_register - wait until register value changes
+ *	@reg: IO-mapped register
+ *	@mask: Mask to apply to read register value
+ *	@val: Wait condition
+ *	@interval_msec: polling interval in milliseconds
+ *	@timeout_msec: timeout in milliseconds
+ *
+ *	Waiting for some bits of register to change is a common
+ *	operation for ATA controllers.  This function reads 32bit LE
+ *	IO-mapped register @reg and tests for the following condition.
+ *
+ *	(*@reg & mask) != val
+ *
+ *	If the condition is met, it returns; otherwise, the process is
+ *	repeated after @interval_msec until timeout.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep)
+ *
+ *	RETURNS:
+ *	The final register value.
+ */
+u32 ata_wait_register(void __iomem *reg, u32 mask, u32 val,
+		      unsigned long interval_msec,
+		      unsigned long timeout_msec)
+{
+	unsigned long timeout;
+	u32 tmp;
+
+	tmp = ioread32(reg);
+
+	/* Calculate timeout _after_ the first read to make sure
+	 * preceding writes reach the controller before starting to
+	 * eat away the timeout.
+	 */
+	timeout = jiffies + (timeout_msec * HZ) / 1000;
+
+	while ((tmp & mask) == val && time_before(jiffies, timeout)) {
+		msleep(interval_msec);
+		tmp = ioread32(reg);
+	}
+
+	return tmp;
+}
+
+/*
+ * Dummy port_ops
+ */
+static void ata_dummy_noret(struct ata_port *ap)	{ }
+static int ata_dummy_ret0(struct ata_port *ap)		{ return 0; }
+static void ata_dummy_qc_noret(struct ata_queued_cmd *qc) { }
+
+static u8 ata_dummy_check_status(struct ata_port *ap)
+{
+	return ATA_DRDY;
+}
+
+static unsigned int ata_dummy_qc_issue(struct ata_queued_cmd *qc)
+{
+	return AC_ERR_SYSTEM;
+}
+
+const struct ata_port_operations ata_dummy_port_ops = {
+	.port_disable		= ata_port_disable,
+	.check_status		= ata_dummy_check_status,
+	.check_altstatus	= ata_dummy_check_status,
+	.dev_select		= ata_noop_dev_select,
+	.qc_prep		= ata_noop_qc_prep,
+	.qc_issue		= ata_dummy_qc_issue,
+	.freeze			= ata_dummy_noret,
+	.thaw			= ata_dummy_noret,
+	.error_handler		= ata_dummy_noret,
+	.post_internal_cmd	= ata_dummy_qc_noret,
+	.irq_clear		= ata_dummy_noret,
+	.port_start		= ata_dummy_ret0,
+	.port_stop		= ata_dummy_noret,
+};
+
+/*
+ * libata is essentially a library of internal helper functions for
+ * low-level ATA host controller drivers.  As such, the API/ABI is
+ * likely to change as new drivers are added and updated.
+ * Do not depend on ABI/API stability.
+ */
+
+EXPORT_SYMBOL_GPL(sata_deb_timing_normal);
+EXPORT_SYMBOL_GPL(sata_deb_timing_hotplug);
+EXPORT_SYMBOL_GPL(sata_deb_timing_long);
+EXPORT_SYMBOL_GPL(ata_dummy_port_ops);
+EXPORT_SYMBOL_GPL(ata_std_bios_param);
+EXPORT_SYMBOL_GPL(ata_std_ports);
+EXPORT_SYMBOL_GPL(ata_host_set_init);
+EXPORT_SYMBOL_GPL(ata_device_add);
+EXPORT_SYMBOL_GPL(ata_port_detach);
+EXPORT_SYMBOL_GPL(ata_host_set_remove);
+EXPORT_SYMBOL_GPL(ata_sg_init);
+EXPORT_SYMBOL_GPL(ata_sg_init_one);
+EXPORT_SYMBOL_GPL(ata_hsm_move);
+EXPORT_SYMBOL_GPL(ata_qc_complete);
+EXPORT_SYMBOL_GPL(ata_qc_complete_multiple);
+EXPORT_SYMBOL_GPL(ata_qc_issue_prot);
+EXPORT_SYMBOL_GPL(ata_tf_load);
+EXPORT_SYMBOL_GPL(ata_tf_read);
+EXPORT_SYMBOL_GPL(ata_noop_dev_select);
+EXPORT_SYMBOL_GPL(ata_std_dev_select);
+EXPORT_SYMBOL_GPL(ata_tf_to_fis);
+EXPORT_SYMBOL_GPL(ata_tf_from_fis);
+EXPORT_SYMBOL_GPL(ata_check_status);
+EXPORT_SYMBOL_GPL(ata_altstatus);
+EXPORT_SYMBOL_GPL(ata_exec_command);
+EXPORT_SYMBOL_GPL(ata_port_start);
+EXPORT_SYMBOL_GPL(ata_port_stop);
+EXPORT_SYMBOL_GPL(ata_host_stop);
+EXPORT_SYMBOL_GPL(ata_interrupt);
+EXPORT_SYMBOL_GPL(ata_mmio_data_xfer);
+EXPORT_SYMBOL_GPL(ata_pio_data_xfer);
+EXPORT_SYMBOL_GPL(ata_pio_data_xfer_noirq);
+EXPORT_SYMBOL_GPL(ata_qc_prep);
+EXPORT_SYMBOL_GPL(ata_noop_qc_prep);
+EXPORT_SYMBOL_GPL(ata_bmdma_setup);
+EXPORT_SYMBOL_GPL(ata_bmdma_start);
+EXPORT_SYMBOL_GPL(ata_bmdma_irq_clear);
+EXPORT_SYMBOL_GPL(ata_bmdma_status);
+EXPORT_SYMBOL_GPL(ata_bmdma_stop);
+EXPORT_SYMBOL_GPL(ata_bmdma_freeze);
+EXPORT_SYMBOL_GPL(ata_bmdma_thaw);
+EXPORT_SYMBOL_GPL(ata_bmdma_drive_eh);
+EXPORT_SYMBOL_GPL(ata_bmdma_error_handler);
+EXPORT_SYMBOL_GPL(ata_bmdma_post_internal_cmd);
+EXPORT_SYMBOL_GPL(ata_port_probe);
+EXPORT_SYMBOL_GPL(sata_set_spd);
+EXPORT_SYMBOL_GPL(sata_phy_debounce);
+EXPORT_SYMBOL_GPL(sata_phy_resume);
+EXPORT_SYMBOL_GPL(sata_phy_reset);
+EXPORT_SYMBOL_GPL(__sata_phy_reset);
+EXPORT_SYMBOL_GPL(ata_bus_reset);
+EXPORT_SYMBOL_GPL(ata_std_prereset);
+EXPORT_SYMBOL_GPL(ata_std_softreset);
+EXPORT_SYMBOL_GPL(sata_std_hardreset);
+EXPORT_SYMBOL_GPL(ata_std_postreset);
+EXPORT_SYMBOL_GPL(ata_dev_revalidate);
+EXPORT_SYMBOL_GPL(ata_dev_classify);
+EXPORT_SYMBOL_GPL(ata_dev_pair);
+EXPORT_SYMBOL_GPL(ata_port_disable);
+EXPORT_SYMBOL_GPL(ata_ratelimit);
+EXPORT_SYMBOL_GPL(ata_wait_register);
+EXPORT_SYMBOL_GPL(ata_busy_sleep);
+EXPORT_SYMBOL_GPL(ata_port_queue_task);
+EXPORT_SYMBOL_GPL(ata_scsi_ioctl);
+EXPORT_SYMBOL_GPL(ata_scsi_queuecmd);
+EXPORT_SYMBOL_GPL(ata_scsi_slave_config);
+EXPORT_SYMBOL_GPL(ata_scsi_slave_destroy);
+EXPORT_SYMBOL_GPL(ata_scsi_change_queue_depth);
+EXPORT_SYMBOL_GPL(ata_scsi_release);
+EXPORT_SYMBOL_GPL(ata_host_intr);
+EXPORT_SYMBOL_GPL(sata_scr_valid);
+EXPORT_SYMBOL_GPL(sata_scr_read);
+EXPORT_SYMBOL_GPL(sata_scr_write);
+EXPORT_SYMBOL_GPL(sata_scr_write_flush);
+EXPORT_SYMBOL_GPL(ata_port_online);
+EXPORT_SYMBOL_GPL(ata_port_offline);
+EXPORT_SYMBOL_GPL(ata_host_set_suspend);
+EXPORT_SYMBOL_GPL(ata_host_set_resume);
+EXPORT_SYMBOL_GPL(ata_id_string);
+EXPORT_SYMBOL_GPL(ata_id_c_string);
+EXPORT_SYMBOL_GPL(ata_scsi_simulate);
+
+EXPORT_SYMBOL_GPL(ata_pio_need_iordy);
+EXPORT_SYMBOL_GPL(ata_timing_compute);
+EXPORT_SYMBOL_GPL(ata_timing_merge);
+
+#ifdef CONFIG_PCI
+EXPORT_SYMBOL_GPL(pci_test_config_bits);
+EXPORT_SYMBOL_GPL(ata_pci_host_stop);
+EXPORT_SYMBOL_GPL(ata_pci_init_native_mode);
+EXPORT_SYMBOL_GPL(ata_pci_init_one);
+EXPORT_SYMBOL_GPL(ata_pci_remove_one);
+EXPORT_SYMBOL_GPL(ata_pci_device_do_suspend);
+EXPORT_SYMBOL_GPL(ata_pci_device_do_resume);
+EXPORT_SYMBOL_GPL(ata_pci_device_suspend);
+EXPORT_SYMBOL_GPL(ata_pci_device_resume);
+EXPORT_SYMBOL_GPL(ata_pci_default_filter);
+EXPORT_SYMBOL_GPL(ata_pci_clear_simplex);
+#endif /* CONFIG_PCI */
+
+EXPORT_SYMBOL_GPL(ata_scsi_device_suspend);
+EXPORT_SYMBOL_GPL(ata_scsi_device_resume);
+
+EXPORT_SYMBOL_GPL(ata_eng_timeout);
+EXPORT_SYMBOL_GPL(ata_port_schedule_eh);
+EXPORT_SYMBOL_GPL(ata_port_abort);
+EXPORT_SYMBOL_GPL(ata_port_freeze);
+EXPORT_SYMBOL_GPL(ata_eh_freeze_port);
+EXPORT_SYMBOL_GPL(ata_eh_thaw_port);
+EXPORT_SYMBOL_GPL(ata_eh_qc_complete);
+EXPORT_SYMBOL_GPL(ata_eh_qc_retry);
+EXPORT_SYMBOL_GPL(ata_do_eh);