[PATCH] xtensa: Architecture support for Tensilica Xtensa Part 8

The attached patches provides part 8 of an architecture implementation
for the Tensilica Xtensa CPU series.

Signed-off-by: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

5 files changed, 1315 insertions, 0 deletions

diff --git a/arch/xtensa/platform-iss/Makefile b/arch/xtensa/platform-iss/Makefile
new file mode 100644
index 000000000000..5b394e9620e5
--- /dev/null
+++ b/arch/xtensa/platform-iss/Makefile
@@ -0,0 +1,13 @@
+# $Id: Makefile,v 1.1.1.1 2002/08/28 16:10:14 aroll Exp $
+#
+# Makefile for the Xtensa Instruction Set Simulator (ISS)
+# "prom monitor" library routines under Linux.
+#
+# Note! Dependencies are done automagically by 'make dep', which also
+# removes any old dependencies. DON'T put your own dependencies here
+# unless it's something special (ie not a .c file).
+#
+# Note 2! The CFLAGS definitions are in the main makefile...
+
+obj-y			= io.o console.o setup.o network.o
+
diff --git a/arch/xtensa/platform-iss/console.c b/arch/xtensa/platform-iss/console.c
new file mode 100644
index 000000000000..9e2b53f6a907
--- /dev/null
+++ b/arch/xtensa/platform-iss/console.c
@@ -0,0 +1,303 @@
+/*
+ * arch/xtensa/platform-iss/console.c
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2001-2005 Tensilica Inc.
+ *   Authors	Christian Zankel, Joe Taylor
+ */
+
+#include <linux/module.h>
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/console.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/major.h>
+#include <linux/param.h>
+#include <linux/serial.h>
+#include <linux/serialP.h>
+#include <linux/console.h>
+
+#include <asm/uaccess.h>
+#include <asm/irq.h>
+
+#include <xtensa/simcall.h>
+
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+
+#ifdef SERIAL_INLINE
+#define _INLINE_ inline
+#endif
+
+#define SERIAL_MAX_NUM_LINES 1
+#define SERIAL_TIMER_VALUE (20 * HZ)
+
+static struct tty_driver *serial_driver;
+static struct timer_list serial_timer;
+
+static DEFINE_SPINLOCK(timer_lock);
+
+int errno;
+
+static int __simc (int a, int b, int c, int d, int e, int f)
+{
+	int ret;
+	__asm__ __volatile__ ("simcall\n"
+			"mov %0, a2\n"
+			"mov %1, a3\n" : "=a" (ret), "=a" (errno)
+			: : "a2", "a3");
+	return ret;
+}
+
+static char *serial_version = "0.1";
+static char *serial_name = "ISS serial driver";
+
+/*
+ * This routine is called whenever a serial port is opened.  It
+ * enables interrupts for a serial port, linking in its async structure into
+ * the IRQ chain.   It also performs the serial-specific
+ * initialization for the tty structure.
+ */
+
+static void rs_poll(unsigned long);
+
+static int rs_open(struct tty_struct *tty, struct file * filp)
+{
+	int line = tty->index;
+
+	if ((line < 0) || (line >= SERIAL_MAX_NUM_LINES))
+		return -ENODEV;
+
+	spin_lock(&timer_lock);
+
+	if (tty->count == 1) {
+		init_timer(&serial_timer);
+		serial_timer.data = (unsigned long) tty;
+		serial_timer.function = rs_poll;
+		mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE);
+	}
+	spin_unlock(&timer_lock);
+
+	return 0;
+}
+
+
+/*
+ * ------------------------------------------------------------
+ * iss_serial_close()
+ *
+ * This routine is called when the serial port gets closed.  First, we
+ * wait for the last remaining data to be sent.  Then, we unlink its
+ * async structure from the interrupt chain if necessary, and we free
+ * that IRQ if nothing is left in the chain.
+ * ------------------------------------------------------------
+ */
+static void rs_close(struct tty_struct *tty, struct file * filp)
+{
+	spin_lock(&timer_lock);
+	if (tty->count == 1)
+		del_timer_sync(&serial_timer);
+	spin_unlock(&timer_lock);
+}
+
+
+static int rs_write(struct tty_struct * tty,
+		    const unsigned char *buf, int count)
+{
+	/* see drivers/char/serialX.c to reference original version */
+
+	__simc (SYS_write, 1, (unsigned long)buf, count, 0, 0);
+	return count;
+}
+
+static void rs_poll(unsigned long priv)
+{
+	struct tty_struct* tty = (struct tty_struct*) priv;
+
+	struct timeval tv = { .tv_sec = 0, .tv_usec = 0 };
+	int i = 0;
+	unsigned char c;
+
+	spin_lock(&timer_lock);
+
+	while (__simc(SYS_select_one, 0, XTISS_SELECT_ONE_READ, (int)&tv,0,0)){
+		__simc (SYS_read, 0, (unsigned long)&c, 1, 0, 0);
+		tty->flip.count++;
+		*tty->flip.char_buf_ptr++ = c;
+		*tty->flip.flag_buf_ptr++ = TTY_NORMAL;
+		i++;
+	}
+
+	if (i)
+		tty_flip_buffer_push(tty);
+
+
+	mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE);
+	spin_unlock(&timer_lock);
+}
+
+
+static void rs_put_char(struct tty_struct *tty, unsigned char ch)
+{
+	char buf[2];
+
+	if (!tty)
+		return;
+
+	buf[0] = ch;
+	buf[1] = '\0';		/* Is this NULL necessary? */
+	__simc (SYS_write, 1, (unsigned long) buf, 1, 0, 0);
+}
+
+static void rs_flush_chars(struct tty_struct *tty)
+{
+}
+
+static int rs_write_room(struct tty_struct *tty)
+{
+	/* Let's say iss can always accept 2K characters.. */
+	return 2 * 1024;
+}
+
+static int rs_chars_in_buffer(struct tty_struct *tty)
+{
+	/* the iss doesn't buffer characters */
+	return 0;
+}
+
+static void rs_hangup(struct tty_struct *tty)
+{
+	/* Stub, once again.. */
+}
+
+static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
+{
+	/* Stub, once again.. */
+}
+
+static int rs_read_proc(char *page, char **start, off_t off, int count,
+			int *eof, void *data)
+{
+	int len = 0;
+	off_t begin = 0;
+
+	len += sprintf(page, "serinfo:1.0 driver:%s\n", serial_version);
+	*eof = 1;
+
+	if (off >= len + begin)
+		return 0;
+
+	*start = page + (off - begin);
+	return ((count < begin + len - off) ? count : begin + len - off);
+}
+
+
+int register_serial(struct serial_struct*);
+void unregister_serial(int);
+
+static struct tty_operations serial_ops = {
+	.open = rs_open,
+	.close = rs_close,
+	.write = rs_write,
+	.put_char = rs_put_char,
+	.flush_chars = rs_flush_chars,
+	.write_room = rs_write_room,
+	.chars_in_buffer = rs_chars_in_buffer,
+	.hangup = rs_hangup,
+	.wait_until_sent = rs_wait_until_sent,
+	.read_proc = rs_read_proc
+};
+
+int __init rs_init(void)
+{
+	serial_driver = alloc_tty_driver(1);
+
+	printk ("%s %s\n", serial_name, serial_version);
+
+	/* Initialize the tty_driver structure */
+
+	serial_driver->owner = THIS_MODULE;
+	serial_driver->driver_name = "iss_serial";
+	serial_driver->name = "ttyS";
+	serial_driver->major = TTY_MAJOR;
+	serial_driver->minor_start = 64;
+	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
+	serial_driver->subtype = SERIAL_TYPE_NORMAL;
+	serial_driver->init_termios = tty_std_termios;
+	serial_driver->init_termios.c_cflag =
+		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
+	serial_driver->flags = TTY_DRIVER_REAL_RAW;
+
+	tty_set_operations(serial_driver, &serial_ops);
+
+	if (tty_register_driver(serial_driver))
+		panic("Couldn't register serial driver\n");
+	return 0;
+}
+
+
+static __exit void rs_exit(void)
+{
+	int error;
+
+	if ((error = tty_unregister_driver(serial_driver)))
+		printk("ISS_SERIAL: failed to unregister serial driver (%d)\n",
+		       error);
+	put_tty_driver(serial_driver);
+}
+
+
+/* We use `late_initcall' instead of just `__initcall' as a workaround for
+ * the fact that (1) simcons_tty_init can't be called before tty_init,
+ * (2) tty_init is called via `module_init', (3) if statically linked,
+ * module_init == device_init, and (4) there's no ordering of init lists.
+ * We can do this easily because simcons is always statically linked, but
+ * other tty drivers that depend on tty_init and which must use
+ * `module_init' to declare their init routines are likely to be broken.
+ */
+
+late_initcall(rs_init);
+
+
+#ifdef CONFIG_SERIAL_CONSOLE
+
+static void iss_console_write(struct console *co, const char *s, unsigned count)
+{
+	int len = strlen(s);
+
+	if (s != 0 && *s != 0)
+		__simc (SYS_write, 1, (unsigned long)s,
+			count < len ? count : len,0,0);
+}
+
+static struct tty_driver* iss_console_device(struct console *c, int *index)
+{
+	*index = c->index;
+	return serial_driver;
+}
+
+
+static struct console sercons = {
+	.name = "ttyS",
+	.write = iss_console_write,
+	.device = iss_console_device,
+	.flags = CON_PRINTBUFFER,
+	.index = -1
+};
+
+static int __init iss_console_init(void)
+{
+	register_console(&sercons);
+	return 0;
+}
+
+console_initcall(iss_console_init);
+
+#endif /* CONFIG_SERIAL_CONSOLE */
+
diff --git a/arch/xtensa/platform-iss/io.c b/arch/xtensa/platform-iss/io.c
new file mode 100644
index 000000000000..5b161a5cb65f
--- /dev/null
+++ b/arch/xtensa/platform-iss/io.c
@@ -0,0 +1,32 @@
+/* This file isn't really needed right now. */
+
+#if 0
+
+#include <asm/io.h>
+#include <xtensa/simcall.h>
+
+extern int __simc ();
+
+
+char iss_serial_getc()
+{
+  char c;
+  __simc( SYS_read, 0, &c, 1 );
+  return c;
+}
+
+void iss_serial_putc( char c )
+{
+  __simc( SYS_write, 1, &c, 1 );
+}
+
+void iss_serial_puts( char *s )
+{
+  if( s != 0 && *s != 0 )
+    __simc( SYS_write, 1, s, strlen(s) );
+}
+
+/*#error Need I/O ports to specific hardware!*/
+
+#endif
+
diff --git a/arch/xtensa/platform-iss/network.c b/arch/xtensa/platform-iss/network.c
new file mode 100644
index 000000000000..498d7dced1f4
--- /dev/null
+++ b/arch/xtensa/platform-iss/network.c
@@ -0,0 +1,855 @@
+/*
+ *
+ * arch/xtensa/platform-iss/network.c
+ *
+ * Platform specific initialization.
+ *
+ * Authors: Chris Zankel <chris@zankel.net>
+ * Based on work form the UML team.
+ *
+ * Copyright 2005 Tensilica Inc.
+ *
+ * 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 of the  License, or (at your
+ * option) any later version.
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/list.h>
+#include <linux/irq.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/timer.h>
+#include <linux/if_ether.h>
+#include <linux/inetdevice.h>
+#include <linux/init.h>
+#include <linux/if_tun.h>
+#include <linux/etherdevice.h>
+#include <linux/interrupt.h>
+#include <linux/ioctl.h>
+#include <linux/bootmem.h>
+#include <linux/ethtool.h>
+#include <linux/rtnetlink.h>
+#include <linux/timer.h>
+
+#include <xtensa/simcall.h>
+
+#define DRIVER_NAME "iss-netdev"
+#define ETH_MAX_PACKET 1500
+#define ETH_HEADER_OTHER 14
+#define ISS_NET_TIMER_VALUE (2 * HZ)
+
+
+static DEFINE_SPINLOCK(opened_lock);
+static LIST_HEAD(opened);
+
+static DEFINE_SPINLOCK(devices_lock);
+static LIST_HEAD(devices);
+
+/* ------------------------------------------------------------------------- */
+
+/* We currently only support the TUNTAP transport protocol. */
+
+#define TRANSPORT_TUNTAP_NAME "tuntap"
+#define TRANSPORT_TUNTAP_MTU ETH_MAX_PACKET
+
+struct tuntap_info {
+	char dev_name[IFNAMSIZ];
+	int fixed_config;
+	unsigned char gw[ETH_ALEN];
+	int fd;
+};
+
+/* ------------------------------------------------------------------------- */
+
+
+/* This structure contains out private information for the driver. */
+
+struct iss_net_private {
+
+	struct list_head device_list;
+	struct list_head opened_list;
+
+	spinlock_t lock;
+	struct net_device *dev;
+	struct platform_device pdev;
+	struct timer_list tl;
+	struct net_device_stats stats;
+
+	struct timer_list timer;
+	unsigned int timer_val;
+
+	int index;
+	int mtu;
+
+	unsigned char mac[ETH_ALEN];
+	int have_mac;
+
+	struct {
+		union {
+			struct tuntap_info tuntap;
+		} info;
+
+		int (*open)(struct iss_net_private *lp);
+		void (*close)(struct iss_net_private *lp);
+		int (*read)(struct iss_net_private *lp, struct sk_buff **skb);
+		int (*write)(struct iss_net_private *lp, struct sk_buff **skb);
+		unsigned short (*protocol)(struct sk_buff *skb);
+		int (*poll)(struct iss_net_private *lp);
+	} tp;
+
+};
+
+/* ======================= ISS SIMCALL INTERFACE =========================== */
+
+/* Note: __simc must _not_ be declared inline! */
+
+static int errno;
+
+static int __simc (int a, int b, int c, int d, int e, int f)
+{
+	int ret;
+	__asm__ __volatile__ ("simcall\n"
+	    		      "mov %0, a2\n"
+			      "mov %1, a3\n" : "=a" (ret), "=a" (errno)
+			      : : "a2", "a3");
+	return ret;
+}
+
+static int inline simc_open(char *file, int flags, int mode)
+{
+	return __simc(SYS_open, (int) file, flags, mode, 0, 0);
+}
+
+static int inline simc_close(int fd)
+{
+	return __simc(SYS_close, fd, 0, 0, 0, 0);
+}
+
+static int inline simc_ioctl(int fd, int request, void *arg)
+{
+	return __simc(SYS_ioctl, fd, request, (int) arg, 0, 0);
+}
+
+static int inline simc_read(int fd, void *buf, size_t count)
+{
+	return __simc(SYS_read, fd, (int) buf, count, 0, 0);
+}
+
+static int inline simc_write(int fd, void *buf, size_t count)
+{
+	return __simc(SYS_write, fd, (int) buf, count, 0, 0);
+}
+
+static int inline simc_poll(int fd)
+{
+	struct timeval tv = { .tv_sec = 0, .tv_usec = 0 };
+
+	return __simc(SYS_select_one, fd, XTISS_SELECT_ONE_READ, (int)&tv,0,0);
+}
+
+/* ================================ HELPERS ================================ */
+
+
+static char *split_if_spec(char *str, ...)
+{
+	char **arg, *end;
+	va_list ap;
+
+	va_start(ap, str);
+	while ((arg = va_arg(ap, char**)) != NULL) {
+		if (*str == '\0')
+			return NULL;
+		end = strchr(str, ',');
+		if (end != str)
+			*arg = str;
+		if (end == NULL)
+			return NULL;
+		*end ++ = '\0';
+		str = end;
+	}
+	va_end(ap);
+	return str;
+}
+
+
+#if 0
+/* Adjust SKB. */
+
+struct sk_buff *ether_adjust_skb(struct sk_buff *skb, int extra)
+{
+	if ((skb != NULL) && (skb_tailroom(skb) < extra)) {
+		struct sk_buff *skb2;
+
+		skb2 = skb_copy_expand(skb, 0, extra, GFP_ATOMIC);
+		dev_kfree_skb(skb);
+		skb = skb2;
+	}
+	if (skb != NULL)
+		skb_put(skb, extra);
+
+	return skb;
+}
+#endif
+
+/* Return the IP address as a string for a given device. */
+
+static void dev_ip_addr(void *d, char *buf, char *bin_buf)
+{
+	struct net_device *dev = d;
+	struct in_device *ip = dev->ip_ptr;
+	struct in_ifaddr *in;
+	u32 addr;
+
+	if ((ip == NULL) || ((in = ip->ifa_list) == NULL)) {
+		printk(KERN_WARNING "Device not assigned an IP address!\n");
+		return;
+	}
+
+	addr = in->ifa_address;
+	sprintf(buf, "%d.%d.%d.%d", addr & 0xff, (addr >> 8) & 0xff,
+		(addr >> 16) & 0xff, addr >> 24);
+
+	if (bin_buf) {
+		bin_buf[0] = addr & 0xff;
+		bin_buf[1] = (addr >> 8) & 0xff;
+		bin_buf[2] = (addr >> 16) & 0xff;
+		bin_buf[3] = addr >> 24;
+	}
+}
+
+/* Set Ethernet address of the specified device. */
+
+static void inline set_ether_mac(void *d, unsigned char *addr)
+{
+	struct net_device *dev = d;
+	memcpy(dev->dev_addr, addr, ETH_ALEN);
+}
+
+
+/* ======================= TUNTAP TRANSPORT INTERFACE ====================== */
+
+static int tuntap_open(struct iss_net_private *lp)
+{
+	struct ifreq ifr;
+	char *dev_name = lp->tp.info.tuntap.dev_name;
+	int err = -EINVAL;
+	int fd;
+
+	/* We currently only support a fixed configuration. */
+
+	if (!lp->tp.info.tuntap.fixed_config)
+		return -EINVAL;
+
+	if ((fd = simc_open("/dev/net/tun", 02, 0)) < 0) {	/* O_RDWR */
+		printk("Failed to open /dev/net/tun, returned %d "
+		       "(errno = %d)\n", fd, errno);
+		return fd;
+	}
+
+	memset(&ifr, 0, sizeof ifr);
+	ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
+	strlcpy(ifr.ifr_name, dev_name, sizeof ifr.ifr_name - 1);
+
+	if ((err = simc_ioctl(fd, TUNSETIFF, (void*) &ifr)) < 0) {
+		printk("Failed to set interface, returned %d "
+		       "(errno = %d)\n", err, errno);
+		simc_close(fd);
+		return err;
+	}
+
+	lp->tp.info.tuntap.fd = fd;
+	return err;
+}
+
+static void tuntap_close(struct iss_net_private *lp)
+{
+#if 0
+	if (lp->tp.info.tuntap.fixed_config)
+		iter_addresses(lp->tp.info.tuntap.dev, close_addr, lp->host.dev_name);
+#endif
+	simc_close(lp->tp.info.tuntap.fd);
+	lp->tp.info.tuntap.fd = -1;
+}
+
+static int tuntap_read (struct iss_net_private *lp, struct sk_buff **skb)
+{
+#if 0
+	*skb = ether_adjust_skb(*skb, ETH_HEADER_OTHER);
+	if (*skb == NULL)
+		return -ENOMEM;
+#endif
+
+	return simc_read(lp->tp.info.tuntap.fd,
+			(*skb)->data, (*skb)->dev->mtu + ETH_HEADER_OTHER);
+}
+
+static int tuntap_write (struct iss_net_private *lp, struct sk_buff **skb)
+{
+	return simc_write(lp->tp.info.tuntap.fd, (*skb)->data, (*skb)->len);
+}
+
+unsigned short tuntap_protocol(struct sk_buff *skb)
+{
+	return eth_type_trans(skb, skb->dev);
+}
+
+static int tuntap_poll(struct iss_net_private *lp)
+{
+	return simc_poll(lp->tp.info.tuntap.fd);
+}
+
+/*
+ * Currently only a device name is supported.
+ * ethX=tuntap[,[mac address][,[device name]]]
+ */
+
+static int tuntap_probe(struct iss_net_private *lp, int index, char *init)
+{
+	const int len = strlen(TRANSPORT_TUNTAP_NAME);
+	char *dev_name = NULL, *mac_str = NULL, *rem = NULL;
+
+	/* Transport should be 'tuntap': ethX=tuntap,mac,dev_name */
+
+	if (strncmp(init, TRANSPORT_TUNTAP_NAME, len))
+		return 0;
+
+	if (*(init += strlen(TRANSPORT_TUNTAP_NAME)) == ',') {
+		if ((rem=split_if_spec(init+1, &mac_str, &dev_name)) != NULL) {
+			printk("Extra garbage on specification : '%s'\n", rem);
+			return 0;
+		}
+	} else if (*init != '\0') {
+		printk("Invalid argument: %s. Skipping device!\n", init);
+		return 0;
+	}
+
+	if (dev_name) {
+		strncpy(lp->tp.info.tuntap.dev_name, dev_name,
+			 sizeof lp->tp.info.tuntap.dev_name);
+		lp->tp.info.tuntap.fixed_config = 1;
+	} else
+		strcpy(lp->tp.info.tuntap.dev_name, TRANSPORT_TUNTAP_NAME);
+
+
+#if 0
+	if (setup_etheraddr(mac_str, lp->mac))
+		lp->have_mac = 1;
+#endif
+	lp->mtu = TRANSPORT_TUNTAP_MTU;
+
+	//lp->info.tuntap.gate_addr = gate_addr;
+
+	lp->tp.info.tuntap.fd = -1;
+
+	lp->tp.open = tuntap_open;
+	lp->tp.close = tuntap_close;
+	lp->tp.read = tuntap_read;
+	lp->tp.write = tuntap_write;
+	lp->tp.protocol = tuntap_protocol;
+	lp->tp.poll = tuntap_poll;
+
+	printk("TUN/TAP backend - ");
+#if 0
+	if (lp->host.gate_addr != NULL)
+		printk("IP = %s", lp->host.gate_addr);
+#endif
+	printk("\n");
+
+	return 1;
+}
+
+/* ================================ ISS NET ================================ */
+
+static int iss_net_rx(struct net_device *dev)
+{
+	struct iss_net_private *lp = dev->priv;
+	int pkt_len;
+	struct sk_buff *skb;
+
+	/* Check if there is any new data. */
+
+	if (lp->tp.poll(lp) == 0)
+		return 0;
+
+	/* Try to allocate memory, if it fails, try again next round. */
+
+	if ((skb = dev_alloc_skb(dev->mtu + 2 + ETH_HEADER_OTHER)) == NULL) {
+		lp->stats.rx_dropped++;
+		return 0;
+	}
+
+	skb_reserve(skb, 2);
+
+	/* Setup skb */
+
+	skb->dev = dev;
+	skb->mac.raw = skb->data;
+	pkt_len = lp->tp.read(lp, &skb);
+	skb_put(skb, pkt_len);
+
+	if (pkt_len > 0) {
+		skb_trim(skb, pkt_len);
+		skb->protocol = lp->tp.protocol(skb);
+	//	netif_rx(skb);
+		netif_rx_ni(skb);
+
+		lp->stats.rx_bytes += skb->len;
+		lp->stats.rx_packets++;
+		return pkt_len;
+	}
+	kfree_skb(skb);
+	return pkt_len;
+}
+
+static int iss_net_poll(void)
+{
+	struct list_head *ele;
+	int err, ret = 0;
+
+	spin_lock(&opened_lock);
+
+	list_for_each(ele, &opened) {
+		struct iss_net_private *lp;
+
+		lp = list_entry(ele, struct iss_net_private, opened_list);
+
+		if (!netif_running(lp->dev))
+			break;
+
+		spin_lock(&lp->lock);
+
+		while ((err = iss_net_rx(lp->dev)) > 0)
+			ret++;
+
+		spin_unlock(&lp->lock);
+
+		if (err < 0) {
+			printk(KERN_ERR "Device '%s' read returned %d, "
+			       "shutting it down\n", lp->dev->name, err);
+			dev_close(lp->dev);
+		} else {
+			// FIXME reactivate_fd(lp->fd, ISS_ETH_IRQ);
+		}
+	}
+
+	spin_unlock(&opened_lock);
+	return ret;
+}
+
+
+static void iss_net_timer(unsigned long priv)
+{
+	struct iss_net_private* lp = (struct iss_net_private*) priv;
+
+	spin_lock(&lp->lock);
+
+	iss_net_poll();
+
+	mod_timer(&lp->timer, jiffies + lp->timer_val);
+
+	spin_unlock(&lp->lock);
+}
+
+
+static int iss_net_open(struct net_device *dev)
+{
+	struct iss_net_private *lp = dev->priv;
+	char addr[sizeof "255.255.255.255\0"];
+	int err;
+
+	spin_lock(&lp->lock);
+
+	if ((err = lp->tp.open(lp)) < 0)
+		goto out;
+
+	if (!lp->have_mac) {
+		dev_ip_addr(dev, addr, &lp->mac[2]);
+		set_ether_mac(dev, lp->mac);
+	}
+
+	netif_start_queue(dev);
+
+	/* clear buffer - it can happen that the host side of the interface
+	 * is full when we gethere. In this case, new data is never queued,
+	 * SIGIOs never arrive, and the net never works.
+	 */
+	while ((err = iss_net_rx(dev)) > 0)
+		;
+
+	spin_lock(&opened_lock);
+	list_add(&lp->opened_list, &opened);
+	spin_unlock(&opened_lock);
+
+	init_timer(&lp->timer);
+	lp->timer_val = ISS_NET_TIMER_VALUE;
+	lp->timer.data = (unsigned long) lp;
+	lp->timer.function = iss_net_timer;
+	mod_timer(&lp->timer, jiffies + lp->timer_val);
+
+out:
+	spin_unlock(&lp->lock);
+	return err;
+}
+
+static int iss_net_close(struct net_device *dev)
+{
+	struct iss_net_private *lp = dev->priv;
+printk("iss_net_close!\n");
+	netif_stop_queue(dev);
+	spin_lock(&lp->lock);
+
+	spin_lock(&opened_lock);
+	list_del(&opened);
+	spin_unlock(&opened_lock);
+
+	del_timer_sync(&lp->timer);
+
+	lp->tp.close(lp);
+
+	spin_unlock(&lp->lock);
+	return 0;
+}
+
+static int iss_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct iss_net_private *lp = dev->priv;
+	unsigned long flags;
+	int len;
+
+	netif_stop_queue(dev);
+	spin_lock_irqsave(&lp->lock, flags);
+
+	len = lp->tp.write(lp, &skb);
+
+	if (len == skb->len) {
+		lp->stats.tx_packets++;
+		lp->stats.tx_bytes += skb->len;
+		dev->trans_start = jiffies;
+		netif_start_queue(dev);
+
+		/* this is normally done in the interrupt when tx finishes */
+		netif_wake_queue(dev);
+
+	} else if (len == 0) {
+		netif_start_queue(dev);
+		lp->stats.tx_dropped++;
+
+	} else {
+		netif_start_queue(dev);
+		printk(KERN_ERR "iss_net_start_xmit: failed(%d)\n", len);
+	}
+
+	spin_unlock_irqrestore(&lp->lock, flags);
+
+	dev_kfree_skb(skb);
+	return 0;
+}
+
+
+static struct net_device_stats *iss_net_get_stats(struct net_device *dev)
+{
+	struct iss_net_private *lp = dev->priv;
+	return &lp->stats;
+}
+
+static void iss_net_set_multicast_list(struct net_device *dev)
+{
+#if 0
+	if (dev->flags & IFF_PROMISC)
+		return;
+	else if (dev->mc_count)
+		dev->flags |= IFF_ALLMULTI;
+	else
+		dev->flags &= ~IFF_ALLMULTI;
+#endif
+}
+
+static void iss_net_tx_timeout(struct net_device *dev)
+{
+#if 0
+	dev->trans_start = jiffies;
+	netif_wake_queue(dev);
+#endif
+}
+
+static int iss_net_set_mac(struct net_device *dev, void *addr)
+{
+#if 0
+	struct iss_net_private *lp = dev->priv;
+	struct sockaddr *hwaddr = addr;
+
+	spin_lock(&lp->lock);
+	memcpy(dev->dev_addr, hwaddr->sa_data, ETH_ALEN);
+	spin_unlock(&lp->lock);
+#endif
+
+	return 0;
+}
+
+static int iss_net_change_mtu(struct net_device *dev, int new_mtu)
+{
+#if 0
+	struct iss_net_private *lp = dev->priv;
+	int err = 0;
+
+	spin_lock(&lp->lock);
+
+	// FIXME not needed new_mtu = transport_set_mtu(new_mtu, &lp->user);
+
+	if (new_mtu < 0)
+		err = new_mtu;
+	else
+		dev->mtu = new_mtu;
+
+	spin_unlock(&lp->lock);
+	return err;
+#endif
+	return -EINVAL;
+}
+
+static int iss_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+#if 0
+	static const struct ethtool_drvinfo info = {
+		.cmd     = ETHTOOL_GDRVINFO,
+		.driver  = DRIVER_NAME,
+		.version = "42",
+	};
+	void *useraddr;
+	u32 ethcmd;
+
+	switch (cmd) {
+	case SIOCETHTOOL:
+		useraddr = ifr->ifr_data;
+		if (copy_from_user(&ethcmd, useraddr, sizeof(ethcmd)))
+			return -EFAULT;
+
+		switch (ethcmd) {
+			case ETHTOOL_GDRVINFO:
+				if (copy_to_user(useraddr, &info, sizeof(info)))
+					return -EFAULT;
+				return 0;
+			default:
+				return -EOPNOTSUPP;
+		}
+	default:
+		return -EINVAL;
+	}
+#endif
+	return -EINVAL;
+}
+
+void iss_net_user_timer_expire(unsigned long _conn)
+{
+}
+
+
+static struct device_driver iss_net_driver = {
+	.name  = DRIVER_NAME,
+	.bus   = &platform_bus_type,
+};
+
+static int driver_registered;
+
+static int iss_net_configure(int index, char *init)
+{
+	struct net_device *dev;
+	struct iss_net_private *lp;
+	int err;
+
+	if ((dev = alloc_etherdev(sizeof *lp)) == NULL) {
+		printk(KERN_ERR "eth_configure: failed to allocate device\n");
+		return 1;
+	}
+
+	/* Initialize private element. */
+
+	lp = dev->priv;
+	*lp = ((struct iss_net_private) {
+		.device_list		= LIST_HEAD_INIT(lp->device_list),
+		.opened_list		= LIST_HEAD_INIT(lp->opened_list),
+		.lock			= SPIN_LOCK_UNLOCKED,
+		.dev			= dev,
+		.index			= index,
+		//.fd                   = -1,
+		.mac			= { 0xfe, 0xfd, 0x0, 0x0, 0x0, 0x0 },
+		.have_mac		= 0,
+		});
+
+	/*
+	 * Try all transport protocols.
+	 * Note: more protocols can be added by adding '&& !X_init(lp, eth)'.
+	 */
+
+	if (!tuntap_probe(lp, index, init)) {
+		printk("Invalid arguments. Skipping device!\n");
+		goto errout;
+	}
+
+	printk(KERN_INFO "Netdevice %d ", index);
+	if (lp->have_mac)
+		printk("(%02x:%02x:%02x:%02x:%02x:%02x) ",
+				lp->mac[0], lp->mac[1],
+				lp->mac[2], lp->mac[3],
+				lp->mac[4], lp->mac[5]);
+	printk(": ");
+
+	/* sysfs register */
+
+	if (!driver_registered) {
+		driver_register(&iss_net_driver);
+		driver_registered = 1;
+	}
+
+	spin_lock(&devices_lock);
+	list_add(&lp->device_list, &devices);
+	spin_unlock(&devices_lock);
+
+	lp->pdev.id = index;
+	lp->pdev.name = DRIVER_NAME;
+	platform_device_register(&lp->pdev);
+	SET_NETDEV_DEV(dev,&lp->pdev.dev);
+
+	/*
+	 * If this name ends up conflicting with an existing registered
+	 * netdevice, that is OK, register_netdev{,ice}() will notice this
+	 * and fail.
+	 */
+	snprintf(dev->name, sizeof dev->name, "eth%d", index);
+
+	dev->mtu = lp->mtu;
+	dev->open = iss_net_open;
+	dev->hard_start_xmit = iss_net_start_xmit;
+	dev->stop = iss_net_close;
+	dev->get_stats = iss_net_get_stats;
+	dev->set_multicast_list = iss_net_set_multicast_list;
+	dev->tx_timeout = iss_net_tx_timeout;
+	dev->set_mac_address = iss_net_set_mac;
+	dev->change_mtu = iss_net_change_mtu;
+	dev->do_ioctl = iss_net_ioctl;
+	dev->watchdog_timeo = (HZ >> 1);
+	dev->irq = -1;
+
+	rtnl_lock();
+	err = register_netdevice(dev);
+	rtnl_unlock();
+
+	if (err) {
+		printk("Error registering net device!\n");
+		/* XXX: should we call ->remove() here? */
+		free_netdev(dev);
+		return 1;
+	}
+
+	init_timer(&lp->tl);
+	lp->tl.function = iss_net_user_timer_expire;
+
+#if 0
+	if (lp->have_mac)
+		set_ether_mac(dev, lp->mac);
+#endif
+	return 0;
+
+errout:
+	// FIXME: unregister; free, etc..
+	return -EIO;
+
+}
+
+/* ------------------------------------------------------------------------- */
+
+/* Filled in during early boot */
+
+struct list_head eth_cmd_line = LIST_HEAD_INIT(eth_cmd_line);
+
+struct iss_net_init {
+	struct list_head list;
+	char *init;		/* init string */
+	int index;
+};
+
+/*
+ * Parse the command line and look for 'ethX=...' fields, and register all
+ * those fields. They will be later initialized in iss_net_init.
+ */
+
+#define ERR KERN_ERR "iss_net_setup: "
+
+static int iss_net_setup(char *str)
+{
+	struct iss_net_private *device = NULL;
+	struct iss_net_init *new;
+	struct list_head *ele;
+	char *end;
+	int n;
+
+	n = simple_strtoul(str, &end, 0);
+	if (end == str) {
+		printk(ERR "Failed to parse '%s'\n", str);
+		return 1;
+	}
+	if (n < 0) {
+		printk(ERR "Device %d is negative\n", n);
+		return 1;
+	}
+	if (*(str = end) != '=') {
+		printk(ERR "Expected '=' after device number\n");
+		return 1;
+	}
+
+	spin_lock(&devices_lock);
+
+	list_for_each(ele, &devices) {
+		device = list_entry(ele, struct iss_net_private, device_list);
+		if (device->index == n)
+			break;
+	}
+
+	spin_unlock(&devices_lock);
+
+	if (device && device->index == n) {
+		printk(ERR "Device %d already configured\n", n);
+		return 1;
+	}
+
+	if ((new = alloc_bootmem(sizeof new)) == NULL) {
+		printk("Alloc_bootmem failed\n");
+		return 1;
+	}
+
+	INIT_LIST_HEAD(&new->list);
+	new->index = n;
+	new->init = str + 1;
+
+	list_add_tail(&new->list, &eth_cmd_line);
+	return 1;
+}
+
+#undef ERR
+
+__setup("eth", iss_net_setup);
+
+/*
+ * Initialize all ISS Ethernet devices previously registered in iss_net_setup.
+ */
+
+static int iss_net_init(void)
+{
+	struct list_head *ele, *next;
+
+	/* Walk through all Ethernet devices specified in the command line. */
+
+	list_for_each_safe(ele, next, &eth_cmd_line) {
+		struct iss_net_init *eth;
+		eth = list_entry(ele, struct iss_net_init, list);
+		iss_net_configure(eth->index, eth->init);
+	}
+
+	return 1;
+}
+
+module_init(iss_net_init);
+
diff --git a/arch/xtensa/platform-iss/setup.c b/arch/xtensa/platform-iss/setup.c
new file mode 100644
index 000000000000..2e6dcbf0cc04
--- /dev/null
+++ b/arch/xtensa/platform-iss/setup.c
@@ -0,0 +1,112 @@
+/*
+ *
+ * arch/xtensa/platform-iss/setup.c
+ *
+ * Platform specific initialization.
+ *
+ * Authors: Chris Zankel <chris@zankel.net>
+ *          Joe Taylor <joe@tensilica.com>
+ *
+ * Copyright 2001 - 2005 Tensilica Inc.
+ *
+ * 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 of the  License, or (at your
+ * option) any later version.
+ *
+ */
+#include <linux/config.h>
+#include <linux/stddef.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/reboot.h>
+#include <linux/pci.h>
+#include <linux/kdev_t.h>
+#include <linux/types.h>
+#include <linux/major.h>
+#include <linux/blkdev.h>
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/stringify.h>
+#include <linux/notifier.h>
+
+#include <asm/platform.h>
+#include <asm/bootparam.h>
+
+
+void __init platform_init(bp_tag_t* bootparam)
+{
+
+}
+
+void platform_halt(void)
+{
+	printk (" ** Called platform_halt(), looping forever! **\n");
+	while (1);
+}
+
+void platform_power_off(void)
+{
+	printk (" ** Called platform_power_off(), looping forever! **\n");
+	while (1);
+}
+void platform_restart(void)
+{
+	/* Flush and reset the mmu, simulate a processor reset, and
+	 * jump to the reset vector. */
+
+	__asm__ __volatile__("movi	a2, 15\n\t"
+			     "wsr	a2, " __stringify(ICOUNTLEVEL) "\n\t"
+			     "movi	a2, 0\n\t"
+			     "wsr	a2, " __stringify(ICOUNT) "\n\t"
+			     "wsr	a2, " __stringify(IBREAKENABLE) "\n\t"
+			     "wsr	a2, " __stringify(LCOUNT) "\n\t"
+			     "movi	a2, 0x1f\n\t"
+			     "wsr	a2, " __stringify(PS) "\n\t"
+			     "isync\n\t"
+			     "jx	%0\n\t"
+			     :
+			     : "a" (XCHAL_RESET_VECTOR_VADDR)
+			     : "a2");
+
+	/* control never gets here */
+}
+
+extern void iss_net_poll(void);
+
+const char twirl[]="|/-\\|/-\\";
+
+void platform_heartbeat(void)
+{
+#if 0
+	static int i = 0, j = 0;
+
+	if (--i < 0) {
+		i = 99;
+		printk("\r%c\r", twirl[j++]);
+		if (j == 8)
+			j = 0;
+	}
+#endif
+}
+
+
+
+static int
+iss_panic_event(struct notifier_block *this, unsigned long event, void *ptr)
+{
+	__asm__ __volatile__("movi a2, -1; simcall\n");
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block iss_panic_block = {
+	iss_panic_event,
+	NULL,
+	0
+};
+
+void __init platform_setup(char **p_cmdline)
+{
+	notifier_chain_register(&panic_notifier_list, &iss_panic_block);
+}