mtd: nand: move raw NAND related code to the raw/ subdir

As part of the process of sharing more code between different NAND
based devices, we need to move all raw NAND related code to the raw/
subdirectory.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>

1 files changed, 1408 insertions, 0 deletions

diff --git a/drivers/mtd/nand/raw/denali.c b/drivers/mtd/nand/raw/denali.c
new file mode 100644
index 000000000000..313c7f50621b
--- /dev/null
+++ b/drivers/mtd/nand/raw/denali.c
@@ -0,0 +1,1408 @@
+/*
+ * NAND Flash Controller Device Driver
+ * Copyright © 2009-2010, Intel Corporation and its suppliers.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/completion.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/rawnand.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include "denali.h"
+
+MODULE_LICENSE("GPL");
+
+#define DENALI_NAND_NAME    "denali-nand"
+
+/* for Indexed Addressing */
+#define DENALI_INDEXED_CTRL	0x00
+#define DENALI_INDEXED_DATA	0x10
+
+#define DENALI_MAP00		(0 << 26)	/* direct access to buffer */
+#define DENALI_MAP01		(1 << 26)	/* read/write pages in PIO */
+#define DENALI_MAP10		(2 << 26)	/* high-level control plane */
+#define DENALI_MAP11		(3 << 26)	/* direct controller access */
+
+/* MAP11 access cycle type */
+#define DENALI_MAP11_CMD	((DENALI_MAP11) | 0)	/* command cycle */
+#define DENALI_MAP11_ADDR	((DENALI_MAP11) | 1)	/* address cycle */
+#define DENALI_MAP11_DATA	((DENALI_MAP11) | 2)	/* data cycle */
+
+/* MAP10 commands */
+#define DENALI_ERASE		0x01
+
+#define DENALI_BANK(denali)	((denali)->active_bank << 24)
+
+#define DENALI_INVALID_BANK	-1
+#define DENALI_NR_BANKS		4
+
+/*
+ * The bus interface clock, clk_x, is phase aligned with the core clock.  The
+ * clk_x is an integral multiple N of the core clk.  The value N is configured
+ * at IP delivery time, and its available value is 4, 5, or 6.  We need to align
+ * to the largest value to make it work with any possible configuration.
+ */
+#define DENALI_CLK_X_MULT	6
+
+static inline struct denali_nand_info *mtd_to_denali(struct mtd_info *mtd)
+{
+	return container_of(mtd_to_nand(mtd), struct denali_nand_info, nand);
+}
+
+/*
+ * Direct Addressing - the slave address forms the control information (command
+ * type, bank, block, and page address).  The slave data is the actual data to
+ * be transferred.  This mode requires 28 bits of address region allocated.
+ */
+static u32 denali_direct_read(struct denali_nand_info *denali, u32 addr)
+{
+	return ioread32(denali->host + addr);
+}
+
+static void denali_direct_write(struct denali_nand_info *denali, u32 addr,
+				u32 data)
+{
+	iowrite32(data, denali->host + addr);
+}
+
+/*
+ * Indexed Addressing - address translation module intervenes in passing the
+ * control information.  This mode reduces the required address range.  The
+ * control information and transferred data are latched by the registers in
+ * the translation module.
+ */
+static u32 denali_indexed_read(struct denali_nand_info *denali, u32 addr)
+{
+	iowrite32(addr, denali->host + DENALI_INDEXED_CTRL);
+	return ioread32(denali->host + DENALI_INDEXED_DATA);
+}
+
+static void denali_indexed_write(struct denali_nand_info *denali, u32 addr,
+				 u32 data)
+{
+	iowrite32(addr, denali->host + DENALI_INDEXED_CTRL);
+	iowrite32(data, denali->host + DENALI_INDEXED_DATA);
+}
+
+/*
+ * Use the configuration feature register to determine the maximum number of
+ * banks that the hardware supports.
+ */
+static void denali_detect_max_banks(struct denali_nand_info *denali)
+{
+	uint32_t features = ioread32(denali->reg + FEATURES);
+
+	denali->max_banks = 1 << FIELD_GET(FEATURES__N_BANKS, features);
+
+	/* the encoding changed from rev 5.0 to 5.1 */
+	if (denali->revision < 0x0501)
+		denali->max_banks <<= 1;
+}
+
+static void denali_enable_irq(struct denali_nand_info *denali)
+{
+	int i;
+
+	for (i = 0; i < DENALI_NR_BANKS; i++)
+		iowrite32(U32_MAX, denali->reg + INTR_EN(i));
+	iowrite32(GLOBAL_INT_EN_FLAG, denali->reg + GLOBAL_INT_ENABLE);
+}
+
+static void denali_disable_irq(struct denali_nand_info *denali)
+{
+	int i;
+
+	for (i = 0; i < DENALI_NR_BANKS; i++)
+		iowrite32(0, denali->reg + INTR_EN(i));
+	iowrite32(0, denali->reg + GLOBAL_INT_ENABLE);
+}
+
+static void denali_clear_irq(struct denali_nand_info *denali,
+			     int bank, uint32_t irq_status)
+{
+	/* write one to clear bits */
+	iowrite32(irq_status, denali->reg + INTR_STATUS(bank));
+}
+
+static void denali_clear_irq_all(struct denali_nand_info *denali)
+{
+	int i;
+
+	for (i = 0; i < DENALI_NR_BANKS; i++)
+		denali_clear_irq(denali, i, U32_MAX);
+}
+
+static irqreturn_t denali_isr(int irq, void *dev_id)
+{
+	struct denali_nand_info *denali = dev_id;
+	irqreturn_t ret = IRQ_NONE;
+	uint32_t irq_status;
+	int i;
+
+	spin_lock(&denali->irq_lock);
+
+	for (i = 0; i < DENALI_NR_BANKS; i++) {
+		irq_status = ioread32(denali->reg + INTR_STATUS(i));
+		if (irq_status)
+			ret = IRQ_HANDLED;
+
+		denali_clear_irq(denali, i, irq_status);
+
+		if (i != denali->active_bank)
+			continue;
+
+		denali->irq_status |= irq_status;
+
+		if (denali->irq_status & denali->irq_mask)
+			complete(&denali->complete);
+	}
+
+	spin_unlock(&denali->irq_lock);
+
+	return ret;
+}
+
+static void denali_reset_irq(struct denali_nand_info *denali)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&denali->irq_lock, flags);
+	denali->irq_status = 0;
+	denali->irq_mask = 0;
+	spin_unlock_irqrestore(&denali->irq_lock, flags);
+}
+
+static uint32_t denali_wait_for_irq(struct denali_nand_info *denali,
+				    uint32_t irq_mask)
+{
+	unsigned long time_left, flags;
+	uint32_t irq_status;
+
+	spin_lock_irqsave(&denali->irq_lock, flags);
+
+	irq_status = denali->irq_status;
+
+	if (irq_mask & irq_status) {
+		/* return immediately if the IRQ has already happened. */
+		spin_unlock_irqrestore(&denali->irq_lock, flags);
+		return irq_status;
+	}
+
+	denali->irq_mask = irq_mask;
+	reinit_completion(&denali->complete);
+	spin_unlock_irqrestore(&denali->irq_lock, flags);
+
+	time_left = wait_for_completion_timeout(&denali->complete,
+						msecs_to_jiffies(1000));
+	if (!time_left) {
+		dev_err(denali->dev, "timeout while waiting for irq 0x%x\n",
+			irq_mask);
+		return 0;
+	}
+
+	return denali->irq_status;
+}
+
+static uint32_t denali_check_irq(struct denali_nand_info *denali)
+{
+	unsigned long flags;
+	uint32_t irq_status;
+
+	spin_lock_irqsave(&denali->irq_lock, flags);
+	irq_status = denali->irq_status;
+	spin_unlock_irqrestore(&denali->irq_lock, flags);
+
+	return irq_status;
+}
+
+static void denali_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+	u32 addr = DENALI_MAP11_DATA | DENALI_BANK(denali);
+	int i;
+
+	for (i = 0; i < len; i++)
+		buf[i] = denali->host_read(denali, addr);
+}
+
+static void denali_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+	u32 addr = DENALI_MAP11_DATA | DENALI_BANK(denali);
+	int i;
+
+	for (i = 0; i < len; i++)
+		denali->host_write(denali, addr, buf[i]);
+}
+
+static void denali_read_buf16(struct mtd_info *mtd, uint8_t *buf, int len)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+	u32 addr = DENALI_MAP11_DATA | DENALI_BANK(denali);
+	uint16_t *buf16 = (uint16_t *)buf;
+	int i;
+
+	for (i = 0; i < len / 2; i++)
+		buf16[i] = denali->host_read(denali, addr);
+}
+
+static void denali_write_buf16(struct mtd_info *mtd, const uint8_t *buf,
+			       int len)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+	u32 addr = DENALI_MAP11_DATA | DENALI_BANK(denali);
+	const uint16_t *buf16 = (const uint16_t *)buf;
+	int i;
+
+	for (i = 0; i < len / 2; i++)
+		denali->host_write(denali, addr, buf16[i]);
+}
+
+static uint8_t denali_read_byte(struct mtd_info *mtd)
+{
+	uint8_t byte;
+
+	denali_read_buf(mtd, &byte, 1);
+
+	return byte;
+}
+
+static void denali_write_byte(struct mtd_info *mtd, uint8_t byte)
+{
+	denali_write_buf(mtd, &byte, 1);
+}
+
+static uint16_t denali_read_word(struct mtd_info *mtd)
+{
+	uint16_t word;
+
+	denali_read_buf16(mtd, (uint8_t *)&word, 2);
+
+	return word;
+}
+
+static void denali_cmd_ctrl(struct mtd_info *mtd, int dat, unsigned int ctrl)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+	uint32_t type;
+
+	if (ctrl & NAND_CLE)
+		type = DENALI_MAP11_CMD;
+	else if (ctrl & NAND_ALE)
+		type = DENALI_MAP11_ADDR;
+	else
+		return;
+
+	/*
+	 * Some commands are followed by chip->dev_ready or chip->waitfunc.
+	 * irq_status must be cleared here to catch the R/B# interrupt later.
+	 */
+	if (ctrl & NAND_CTRL_CHANGE)
+		denali_reset_irq(denali);
+
+	denali->host_write(denali, DENALI_BANK(denali) | type, dat);
+}
+
+static int denali_dev_ready(struct mtd_info *mtd)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+
+	return !!(denali_check_irq(denali) & INTR__INT_ACT);
+}
+
+static int denali_check_erased_page(struct mtd_info *mtd,
+				    struct nand_chip *chip, uint8_t *buf,
+				    unsigned long uncor_ecc_flags,
+				    unsigned int max_bitflips)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+	uint8_t *ecc_code = chip->oob_poi + denali->oob_skip_bytes;
+	int ecc_steps = chip->ecc.steps;
+	int ecc_size = chip->ecc.size;
+	int ecc_bytes = chip->ecc.bytes;
+	int i, stat;
+
+	for (i = 0; i < ecc_steps; i++) {
+		if (!(uncor_ecc_flags & BIT(i)))
+			continue;
+
+		stat = nand_check_erased_ecc_chunk(buf, ecc_size,
+						  ecc_code, ecc_bytes,
+						  NULL, 0,
+						  chip->ecc.strength);
+		if (stat < 0) {
+			mtd->ecc_stats.failed++;
+		} else {
+			mtd->ecc_stats.corrected += stat;
+			max_bitflips = max_t(unsigned int, max_bitflips, stat);
+		}
+
+		buf += ecc_size;
+		ecc_code += ecc_bytes;
+	}
+
+	return max_bitflips;
+}
+
+static int denali_hw_ecc_fixup(struct mtd_info *mtd,
+			       struct denali_nand_info *denali,
+			       unsigned long *uncor_ecc_flags)
+{
+	struct nand_chip *chip = mtd_to_nand(mtd);
+	int bank = denali->active_bank;
+	uint32_t ecc_cor;
+	unsigned int max_bitflips;
+
+	ecc_cor = ioread32(denali->reg + ECC_COR_INFO(bank));
+	ecc_cor >>= ECC_COR_INFO__SHIFT(bank);
+
+	if (ecc_cor & ECC_COR_INFO__UNCOR_ERR) {
+		/*
+		 * This flag is set when uncorrectable error occurs at least in
+		 * one ECC sector.  We can not know "how many sectors", or
+		 * "which sector(s)".  We need erase-page check for all sectors.
+		 */
+		*uncor_ecc_flags = GENMASK(chip->ecc.steps - 1, 0);
+		return 0;
+	}
+
+	max_bitflips = FIELD_GET(ECC_COR_INFO__MAX_ERRORS, ecc_cor);
+
+	/*
+	 * The register holds the maximum of per-sector corrected bitflips.
+	 * This is suitable for the return value of the ->read_page() callback.
+	 * Unfortunately, we can not know the total number of corrected bits in
+	 * the page.  Increase the stats by max_bitflips. (compromised solution)
+	 */
+	mtd->ecc_stats.corrected += max_bitflips;
+
+	return max_bitflips;
+}
+
+static int denali_sw_ecc_fixup(struct mtd_info *mtd,
+			       struct denali_nand_info *denali,
+			       unsigned long *uncor_ecc_flags, uint8_t *buf)
+{
+	unsigned int ecc_size = denali->nand.ecc.size;
+	unsigned int bitflips = 0;
+	unsigned int max_bitflips = 0;
+	uint32_t err_addr, err_cor_info;
+	unsigned int err_byte, err_sector, err_device;
+	uint8_t err_cor_value;
+	unsigned int prev_sector = 0;
+	uint32_t irq_status;
+
+	denali_reset_irq(denali);
+
+	do {
+		err_addr = ioread32(denali->reg + ECC_ERROR_ADDRESS);
+		err_sector = FIELD_GET(ECC_ERROR_ADDRESS__SECTOR, err_addr);
+		err_byte = FIELD_GET(ECC_ERROR_ADDRESS__OFFSET, err_addr);
+
+		err_cor_info = ioread32(denali->reg + ERR_CORRECTION_INFO);
+		err_cor_value = FIELD_GET(ERR_CORRECTION_INFO__BYTE,
+					  err_cor_info);
+		err_device = FIELD_GET(ERR_CORRECTION_INFO__DEVICE,
+				       err_cor_info);
+
+		/* reset the bitflip counter when crossing ECC sector */
+		if (err_sector != prev_sector)
+			bitflips = 0;
+
+		if (err_cor_info & ERR_CORRECTION_INFO__UNCOR) {
+			/*
+			 * Check later if this is a real ECC error, or
+			 * an erased sector.
+			 */
+			*uncor_ecc_flags |= BIT(err_sector);
+		} else if (err_byte < ecc_size) {
+			/*
+			 * If err_byte is larger than ecc_size, means error
+			 * happened in OOB, so we ignore it. It's no need for
+			 * us to correct it err_device is represented the NAND
+			 * error bits are happened in if there are more than
+			 * one NAND connected.
+			 */
+			int offset;
+			unsigned int flips_in_byte;
+
+			offset = (err_sector * ecc_size + err_byte) *
+					denali->devs_per_cs + err_device;
+
+			/* correct the ECC error */
+			flips_in_byte = hweight8(buf[offset] ^ err_cor_value);
+			buf[offset] ^= err_cor_value;
+			mtd->ecc_stats.corrected += flips_in_byte;
+			bitflips += flips_in_byte;
+
+			max_bitflips = max(max_bitflips, bitflips);
+		}
+
+		prev_sector = err_sector;
+	} while (!(err_cor_info & ERR_CORRECTION_INFO__LAST_ERR));
+
+	/*
+	 * Once handle all ECC errors, controller will trigger an
+	 * ECC_TRANSACTION_DONE interrupt.
+	 */
+	irq_status = denali_wait_for_irq(denali, INTR__ECC_TRANSACTION_DONE);
+	if (!(irq_status & INTR__ECC_TRANSACTION_DONE))
+		return -EIO;
+
+	return max_bitflips;
+}
+
+static void denali_setup_dma64(struct denali_nand_info *denali,
+			       dma_addr_t dma_addr, int page, int write)
+{
+	uint32_t mode;
+	const int page_count = 1;
+
+	mode = DENALI_MAP10 | DENALI_BANK(denali) | page;
+
+	/* DMA is a three step process */
+
+	/*
+	 * 1. setup transfer type, interrupt when complete,
+	 *    burst len = 64 bytes, the number of pages
+	 */
+	denali->host_write(denali, mode,
+			   0x01002000 | (64 << 16) | (write << 8) | page_count);
+
+	/* 2. set memory low address */
+	denali->host_write(denali, mode, lower_32_bits(dma_addr));
+
+	/* 3. set memory high address */
+	denali->host_write(denali, mode, upper_32_bits(dma_addr));
+}
+
+static void denali_setup_dma32(struct denali_nand_info *denali,
+			       dma_addr_t dma_addr, int page, int write)
+{
+	uint32_t mode;
+	const int page_count = 1;
+
+	mode = DENALI_MAP10 | DENALI_BANK(denali);
+
+	/* DMA is a four step process */
+
+	/* 1. setup transfer type and # of pages */
+	denali->host_write(denali, mode | page,
+			   0x2000 | (write << 8) | page_count);
+
+	/* 2. set memory high address bits 23:8 */
+	denali->host_write(denali, mode | ((dma_addr >> 16) << 8), 0x2200);
+
+	/* 3. set memory low address bits 23:8 */
+	denali->host_write(denali, mode | ((dma_addr & 0xffff) << 8), 0x2300);
+
+	/* 4. interrupt when complete, burst len = 64 bytes */
+	denali->host_write(denali, mode | 0x14000, 0x2400);
+}
+
+static int denali_pio_read(struct denali_nand_info *denali, void *buf,
+			   size_t size, int page, int raw)
+{
+	u32 addr = DENALI_MAP01 | DENALI_BANK(denali) | page;
+	uint32_t *buf32 = (uint32_t *)buf;
+	uint32_t irq_status, ecc_err_mask;
+	int i;
+
+	if (denali->caps & DENALI_CAP_HW_ECC_FIXUP)
+		ecc_err_mask = INTR__ECC_UNCOR_ERR;
+	else
+		ecc_err_mask = INTR__ECC_ERR;
+
+	denali_reset_irq(denali);
+
+	for (i = 0; i < size / 4; i++)
+		*buf32++ = denali->host_read(denali, addr);
+
+	irq_status = denali_wait_for_irq(denali, INTR__PAGE_XFER_INC);
+	if (!(irq_status & INTR__PAGE_XFER_INC))
+		return -EIO;
+
+	if (irq_status & INTR__ERASED_PAGE)
+		memset(buf, 0xff, size);
+
+	return irq_status & ecc_err_mask ? -EBADMSG : 0;
+}
+
+static int denali_pio_write(struct denali_nand_info *denali,
+			    const void *buf, size_t size, int page, int raw)
+{
+	u32 addr = DENALI_MAP01 | DENALI_BANK(denali) | page;
+	const uint32_t *buf32 = (uint32_t *)buf;
+	uint32_t irq_status;
+	int i;
+
+	denali_reset_irq(denali);
+
+	for (i = 0; i < size / 4; i++)
+		denali->host_write(denali, addr, *buf32++);
+
+	irq_status = denali_wait_for_irq(denali,
+				INTR__PROGRAM_COMP | INTR__PROGRAM_FAIL);
+	if (!(irq_status & INTR__PROGRAM_COMP))
+		return -EIO;
+
+	return 0;
+}
+
+static int denali_pio_xfer(struct denali_nand_info *denali, void *buf,
+			   size_t size, int page, int raw, int write)
+{
+	if (write)
+		return denali_pio_write(denali, buf, size, page, raw);
+	else
+		return denali_pio_read(denali, buf, size, page, raw);
+}
+
+static int denali_dma_xfer(struct denali_nand_info *denali, void *buf,
+			   size_t size, int page, int raw, int write)
+{
+	dma_addr_t dma_addr;
+	uint32_t irq_mask, irq_status, ecc_err_mask;
+	enum dma_data_direction dir = write ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
+	int ret = 0;
+
+	dma_addr = dma_map_single(denali->dev, buf, size, dir);
+	if (dma_mapping_error(denali->dev, dma_addr)) {
+		dev_dbg(denali->dev, "Failed to DMA-map buffer. Trying PIO.\n");
+		return denali_pio_xfer(denali, buf, size, page, raw, write);
+	}
+
+	if (write) {
+		/*
+		 * INTR__PROGRAM_COMP is never asserted for the DMA transfer.
+		 * We can use INTR__DMA_CMD_COMP instead.  This flag is asserted
+		 * when the page program is completed.
+		 */
+		irq_mask = INTR__DMA_CMD_COMP | INTR__PROGRAM_FAIL;
+		ecc_err_mask = 0;
+	} else if (denali->caps & DENALI_CAP_HW_ECC_FIXUP) {
+		irq_mask = INTR__DMA_CMD_COMP;
+		ecc_err_mask = INTR__ECC_UNCOR_ERR;
+	} else {
+		irq_mask = INTR__DMA_CMD_COMP;
+		ecc_err_mask = INTR__ECC_ERR;
+	}
+
+	iowrite32(DMA_ENABLE__FLAG, denali->reg + DMA_ENABLE);
+
+	denali_reset_irq(denali);
+	denali->setup_dma(denali, dma_addr, page, write);
+
+	irq_status = denali_wait_for_irq(denali, irq_mask);
+	if (!(irq_status & INTR__DMA_CMD_COMP))
+		ret = -EIO;
+	else if (irq_status & ecc_err_mask)
+		ret = -EBADMSG;
+
+	iowrite32(0, denali->reg + DMA_ENABLE);
+
+	dma_unmap_single(denali->dev, dma_addr, size, dir);
+
+	if (irq_status & INTR__ERASED_PAGE)
+		memset(buf, 0xff, size);
+
+	return ret;
+}
+
+static int denali_data_xfer(struct denali_nand_info *denali, void *buf,
+			    size_t size, int page, int raw, int write)
+{
+	iowrite32(raw ? 0 : ECC_ENABLE__FLAG, denali->reg + ECC_ENABLE);
+	iowrite32(raw ? TRANSFER_SPARE_REG__FLAG : 0,
+		  denali->reg + TRANSFER_SPARE_REG);
+
+	if (denali->dma_avail)
+		return denali_dma_xfer(denali, buf, size, page, raw, write);
+	else
+		return denali_pio_xfer(denali, buf, size, page, raw, write);
+}
+
+static void denali_oob_xfer(struct mtd_info *mtd, struct nand_chip *chip,
+			    int page, int write)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+	int writesize = mtd->writesize;
+	int oobsize = mtd->oobsize;
+	uint8_t *bufpoi = chip->oob_poi;
+	int ecc_steps = chip->ecc.steps;
+	int ecc_size = chip->ecc.size;
+	int ecc_bytes = chip->ecc.bytes;
+	int oob_skip = denali->oob_skip_bytes;
+	size_t size = writesize + oobsize;
+	int i, pos, len;
+
+	/* BBM at the beginning of the OOB area */
+	if (write)
+		nand_prog_page_begin_op(chip, page, writesize, bufpoi,
+					oob_skip);
+	else
+		nand_read_page_op(chip, page, writesize, bufpoi, oob_skip);
+	bufpoi += oob_skip;
+
+	/* OOB ECC */
+	for (i = 0; i < ecc_steps; i++) {
+		pos = ecc_size + i * (ecc_size + ecc_bytes);
+		len = ecc_bytes;
+
+		if (pos >= writesize)
+			pos += oob_skip;
+		else if (pos + len > writesize)
+			len = writesize - pos;
+
+		if (write)
+			nand_change_write_column_op(chip, pos, bufpoi, len,
+						    false);
+		else
+			nand_change_read_column_op(chip, pos, bufpoi, len,
+						   false);
+		bufpoi += len;
+		if (len < ecc_bytes) {
+			len = ecc_bytes - len;
+			if (write)
+				nand_change_write_column_op(chip, writesize +
+							    oob_skip, bufpoi,
+							    len, false);
+			else
+				nand_change_read_column_op(chip, writesize +
+							   oob_skip, bufpoi,
+							   len, false);
+			bufpoi += len;
+		}
+	}
+
+	/* OOB free */
+	len = oobsize - (bufpoi - chip->oob_poi);
+	if (write)
+		nand_change_write_column_op(chip, size - len, bufpoi, len,
+					    false);
+	else
+		nand_change_read_column_op(chip, size - len, bufpoi, len,
+					   false);
+}
+
+static int denali_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
+				uint8_t *buf, int oob_required, int page)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+	int writesize = mtd->writesize;
+	int oobsize = mtd->oobsize;
+	int ecc_steps = chip->ecc.steps;
+	int ecc_size = chip->ecc.size;
+	int ecc_bytes = chip->ecc.bytes;
+	void *tmp_buf = denali->buf;
+	int oob_skip = denali->oob_skip_bytes;
+	size_t size = writesize + oobsize;
+	int ret, i, pos, len;
+
+	ret = denali_data_xfer(denali, tmp_buf, size, page, 1, 0);
+	if (ret)
+		return ret;
+
+	/* Arrange the buffer for syndrome payload/ecc layout */
+	if (buf) {
+		for (i = 0; i < ecc_steps; i++) {
+			pos = i * (ecc_size + ecc_bytes);
+			len = ecc_size;
+
+			if (pos >= writesize)
+				pos += oob_skip;
+			else if (pos + len > writesize)
+				len = writesize - pos;
+
+			memcpy(buf, tmp_buf + pos, len);
+			buf += len;
+			if (len < ecc_size) {
+				len = ecc_size - len;
+				memcpy(buf, tmp_buf + writesize + oob_skip,
+				       len);
+				buf += len;
+			}
+		}
+	}
+
+	if (oob_required) {
+		uint8_t *oob = chip->oob_poi;
+
+		/* BBM at the beginning of the OOB area */
+		memcpy(oob, tmp_buf + writesize, oob_skip);
+		oob += oob_skip;
+
+		/* OOB ECC */
+		for (i = 0; i < ecc_steps; i++) {
+			pos = ecc_size + i * (ecc_size + ecc_bytes);
+			len = ecc_bytes;
+
+			if (pos >= writesize)
+				pos += oob_skip;
+			else if (pos + len > writesize)
+				len = writesize - pos;
+
+			memcpy(oob, tmp_buf + pos, len);
+			oob += len;
+			if (len < ecc_bytes) {
+				len = ecc_bytes - len;
+				memcpy(oob, tmp_buf + writesize + oob_skip,
+				       len);
+				oob += len;
+			}
+		}
+
+		/* OOB free */
+		len = oobsize - (oob - chip->oob_poi);
+		memcpy(oob, tmp_buf + size - len, len);
+	}
+
+	return 0;
+}
+
+static int denali_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
+			   int page)
+{
+	denali_oob_xfer(mtd, chip, page, 0);
+
+	return 0;
+}
+
+static int denali_write_oob(struct mtd_info *mtd, struct nand_chip *chip,
+			    int page)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+
+	denali_reset_irq(denali);
+
+	denali_oob_xfer(mtd, chip, page, 1);
+
+	return nand_prog_page_end_op(chip);
+}
+
+static int denali_read_page(struct mtd_info *mtd, struct nand_chip *chip,
+			    uint8_t *buf, int oob_required, int page)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+	unsigned long uncor_ecc_flags = 0;
+	int stat = 0;
+	int ret;
+
+	ret = denali_data_xfer(denali, buf, mtd->writesize, page, 0, 0);
+	if (ret && ret != -EBADMSG)
+		return ret;
+
+	if (denali->caps & DENALI_CAP_HW_ECC_FIXUP)
+		stat = denali_hw_ecc_fixup(mtd, denali, &uncor_ecc_flags);
+	else if (ret == -EBADMSG)
+		stat = denali_sw_ecc_fixup(mtd, denali, &uncor_ecc_flags, buf);
+
+	if (stat < 0)
+		return stat;
+
+	if (uncor_ecc_flags) {
+		ret = denali_read_oob(mtd, chip, page);
+		if (ret)
+			return ret;
+
+		stat = denali_check_erased_page(mtd, chip, buf,
+						uncor_ecc_flags, stat);
+	}
+
+	return stat;
+}
+
+static int denali_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
+				 const uint8_t *buf, int oob_required, int page)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+	int writesize = mtd->writesize;
+	int oobsize = mtd->oobsize;
+	int ecc_steps = chip->ecc.steps;
+	int ecc_size = chip->ecc.size;
+	int ecc_bytes = chip->ecc.bytes;
+	void *tmp_buf = denali->buf;
+	int oob_skip = denali->oob_skip_bytes;
+	size_t size = writesize + oobsize;
+	int i, pos, len;
+
+	/*
+	 * Fill the buffer with 0xff first except the full page transfer.
+	 * This simplifies the logic.
+	 */
+	if (!buf || !oob_required)
+		memset(tmp_buf, 0xff, size);
+
+	/* Arrange the buffer for syndrome payload/ecc layout */
+	if (buf) {
+		for (i = 0; i < ecc_steps; i++) {
+			pos = i * (ecc_size + ecc_bytes);
+			len = ecc_size;
+
+			if (pos >= writesize)
+				pos += oob_skip;
+			else if (pos + len > writesize)
+				len = writesize - pos;
+
+			memcpy(tmp_buf + pos, buf, len);
+			buf += len;
+			if (len < ecc_size) {
+				len = ecc_size - len;
+				memcpy(tmp_buf + writesize + oob_skip, buf,
+				       len);
+				buf += len;
+			}
+		}
+	}
+
+	if (oob_required) {
+		const uint8_t *oob = chip->oob_poi;
+
+		/* BBM at the beginning of the OOB area */
+		memcpy(tmp_buf + writesize, oob, oob_skip);
+		oob += oob_skip;
+
+		/* OOB ECC */
+		for (i = 0; i < ecc_steps; i++) {
+			pos = ecc_size + i * (ecc_size + ecc_bytes);
+			len = ecc_bytes;
+
+			if (pos >= writesize)
+				pos += oob_skip;
+			else if (pos + len > writesize)
+				len = writesize - pos;
+
+			memcpy(tmp_buf + pos, oob, len);
+			oob += len;
+			if (len < ecc_bytes) {
+				len = ecc_bytes - len;
+				memcpy(tmp_buf + writesize + oob_skip, oob,
+				       len);
+				oob += len;
+			}
+		}
+
+		/* OOB free */
+		len = oobsize - (oob - chip->oob_poi);
+		memcpy(tmp_buf + size - len, oob, len);
+	}
+
+	return denali_data_xfer(denali, tmp_buf, size, page, 1, 1);
+}
+
+static int denali_write_page(struct mtd_info *mtd, struct nand_chip *chip,
+			     const uint8_t *buf, int oob_required, int page)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+
+	return denali_data_xfer(denali, (void *)buf, mtd->writesize,
+				page, 0, 1);
+}
+
+static void denali_select_chip(struct mtd_info *mtd, int chip)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+
+	denali->active_bank = chip;
+}
+
+static int denali_waitfunc(struct mtd_info *mtd, struct nand_chip *chip)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+	uint32_t irq_status;
+
+	/* R/B# pin transitioned from low to high? */
+	irq_status = denali_wait_for_irq(denali, INTR__INT_ACT);
+
+	return irq_status & INTR__INT_ACT ? 0 : NAND_STATUS_FAIL;
+}
+
+static int denali_erase(struct mtd_info *mtd, int page)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+	uint32_t irq_status;
+
+	denali_reset_irq(denali);
+
+	denali->host_write(denali, DENALI_MAP10 | DENALI_BANK(denali) | page,
+			   DENALI_ERASE);
+
+	/* wait for erase to complete or failure to occur */
+	irq_status = denali_wait_for_irq(denali,
+					 INTR__ERASE_COMP | INTR__ERASE_FAIL);
+
+	return irq_status & INTR__ERASE_COMP ? 0 : -EIO;
+}
+
+static int denali_setup_data_interface(struct mtd_info *mtd, int chipnr,
+				       const struct nand_data_interface *conf)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+	const struct nand_sdr_timings *timings;
+	unsigned long t_clk;
+	int acc_clks, re_2_we, re_2_re, we_2_re, addr_2_data;
+	int rdwr_en_lo, rdwr_en_hi, rdwr_en_lo_hi, cs_setup;
+	int addr_2_data_mask;
+	uint32_t tmp;
+
+	timings = nand_get_sdr_timings(conf);
+	if (IS_ERR(timings))
+		return PTR_ERR(timings);
+
+	/* clk_x period in picoseconds */
+	t_clk = DIV_ROUND_DOWN_ULL(1000000000000ULL, denali->clk_x_rate);
+	if (!t_clk)
+		return -EINVAL;
+
+	if (chipnr == NAND_DATA_IFACE_CHECK_ONLY)
+		return 0;
+
+	/* tREA -> ACC_CLKS */
+	acc_clks = DIV_ROUND_UP(timings->tREA_max, t_clk);
+	acc_clks = min_t(int, acc_clks, ACC_CLKS__VALUE);
+
+	tmp = ioread32(denali->reg + ACC_CLKS);
+	tmp &= ~ACC_CLKS__VALUE;
+	tmp |= FIELD_PREP(ACC_CLKS__VALUE, acc_clks);
+	iowrite32(tmp, denali->reg + ACC_CLKS);
+
+	/* tRWH -> RE_2_WE */
+	re_2_we = DIV_ROUND_UP(timings->tRHW_min, t_clk);
+	re_2_we = min_t(int, re_2_we, RE_2_WE__VALUE);
+
+	tmp = ioread32(denali->reg + RE_2_WE);
+	tmp &= ~RE_2_WE__VALUE;
+	tmp |= FIELD_PREP(RE_2_WE__VALUE, re_2_we);
+	iowrite32(tmp, denali->reg + RE_2_WE);
+
+	/* tRHZ -> RE_2_RE */
+	re_2_re = DIV_ROUND_UP(timings->tRHZ_max, t_clk);
+	re_2_re = min_t(int, re_2_re, RE_2_RE__VALUE);
+
+	tmp = ioread32(denali->reg + RE_2_RE);
+	tmp &= ~RE_2_RE__VALUE;
+	tmp |= FIELD_PREP(RE_2_RE__VALUE, re_2_re);
+	iowrite32(tmp, denali->reg + RE_2_RE);
+
+	/*
+	 * tCCS, tWHR -> WE_2_RE
+	 *
+	 * With WE_2_RE properly set, the Denali controller automatically takes
+	 * care of the delay; the driver need not set NAND_WAIT_TCCS.
+	 */
+	we_2_re = DIV_ROUND_UP(max(timings->tCCS_min, timings->tWHR_min),
+			       t_clk);
+	we_2_re = min_t(int, we_2_re, TWHR2_AND_WE_2_RE__WE_2_RE);
+
+	tmp = ioread32(denali->reg + TWHR2_AND_WE_2_RE);
+	tmp &= ~TWHR2_AND_WE_2_RE__WE_2_RE;
+	tmp |= FIELD_PREP(TWHR2_AND_WE_2_RE__WE_2_RE, we_2_re);
+	iowrite32(tmp, denali->reg + TWHR2_AND_WE_2_RE);
+
+	/* tADL -> ADDR_2_DATA */
+
+	/* for older versions, ADDR_2_DATA is only 6 bit wide */
+	addr_2_data_mask = TCWAW_AND_ADDR_2_DATA__ADDR_2_DATA;
+	if (denali->revision < 0x0501)
+		addr_2_data_mask >>= 1;
+
+	addr_2_data = DIV_ROUND_UP(timings->tADL_min, t_clk);
+	addr_2_data = min_t(int, addr_2_data, addr_2_data_mask);
+
+	tmp = ioread32(denali->reg + TCWAW_AND_ADDR_2_DATA);
+	tmp &= ~TCWAW_AND_ADDR_2_DATA__ADDR_2_DATA;
+	tmp |= FIELD_PREP(TCWAW_AND_ADDR_2_DATA__ADDR_2_DATA, addr_2_data);
+	iowrite32(tmp, denali->reg + TCWAW_AND_ADDR_2_DATA);
+
+	/* tREH, tWH -> RDWR_EN_HI_CNT */
+	rdwr_en_hi = DIV_ROUND_UP(max(timings->tREH_min, timings->tWH_min),
+				  t_clk);
+	rdwr_en_hi = min_t(int, rdwr_en_hi, RDWR_EN_HI_CNT__VALUE);
+
+	tmp = ioread32(denali->reg + RDWR_EN_HI_CNT);
+	tmp &= ~RDWR_EN_HI_CNT__VALUE;
+	tmp |= FIELD_PREP(RDWR_EN_HI_CNT__VALUE, rdwr_en_hi);
+	iowrite32(tmp, denali->reg + RDWR_EN_HI_CNT);
+
+	/* tRP, tWP -> RDWR_EN_LO_CNT */
+	rdwr_en_lo = DIV_ROUND_UP(max(timings->tRP_min, timings->tWP_min),
+				  t_clk);
+	rdwr_en_lo_hi = DIV_ROUND_UP(max(timings->tRC_min, timings->tWC_min),
+				     t_clk);
+	rdwr_en_lo_hi = max(rdwr_en_lo_hi, DENALI_CLK_X_MULT);
+	rdwr_en_lo = max(rdwr_en_lo, rdwr_en_lo_hi - rdwr_en_hi);
+	rdwr_en_lo = min_t(int, rdwr_en_lo, RDWR_EN_LO_CNT__VALUE);
+
+	tmp = ioread32(denali->reg + RDWR_EN_LO_CNT);
+	tmp &= ~RDWR_EN_LO_CNT__VALUE;
+	tmp |= FIELD_PREP(RDWR_EN_LO_CNT__VALUE, rdwr_en_lo);
+	iowrite32(tmp, denali->reg + RDWR_EN_LO_CNT);
+
+	/* tCS, tCEA -> CS_SETUP_CNT */
+	cs_setup = max3((int)DIV_ROUND_UP(timings->tCS_min, t_clk) - rdwr_en_lo,
+			(int)DIV_ROUND_UP(timings->tCEA_max, t_clk) - acc_clks,
+			0);
+	cs_setup = min_t(int, cs_setup, CS_SETUP_CNT__VALUE);
+
+	tmp = ioread32(denali->reg + CS_SETUP_CNT);
+	tmp &= ~CS_SETUP_CNT__VALUE;
+	tmp |= FIELD_PREP(CS_SETUP_CNT__VALUE, cs_setup);
+	iowrite32(tmp, denali->reg + CS_SETUP_CNT);
+
+	return 0;
+}
+
+static void denali_reset_banks(struct denali_nand_info *denali)
+{
+	u32 irq_status;
+	int i;
+
+	for (i = 0; i < denali->max_banks; i++) {
+		denali->active_bank = i;
+
+		denali_reset_irq(denali);
+
+		iowrite32(DEVICE_RESET__BANK(i),
+			  denali->reg + DEVICE_RESET);
+
+		irq_status = denali_wait_for_irq(denali,
+			INTR__RST_COMP | INTR__INT_ACT | INTR__TIME_OUT);
+		if (!(irq_status & INTR__INT_ACT))
+			break;
+	}
+
+	dev_dbg(denali->dev, "%d chips connected\n", i);
+	denali->max_banks = i;
+}
+
+static void denali_hw_init(struct denali_nand_info *denali)
+{
+	/*
+	 * The REVISION register may not be reliable.  Platforms are allowed to
+	 * override it.
+	 */
+	if (!denali->revision)
+		denali->revision = swab16(ioread32(denali->reg + REVISION));
+
+	/*
+	 * tell driver how many bit controller will skip before
+	 * writing ECC code in OOB, this register may be already
+	 * set by firmware. So we read this value out.
+	 * if this value is 0, just let it be.
+	 */
+	denali->oob_skip_bytes = ioread32(denali->reg + SPARE_AREA_SKIP_BYTES);
+	denali_detect_max_banks(denali);
+	iowrite32(0x0F, denali->reg + RB_PIN_ENABLED);
+	iowrite32(CHIP_EN_DONT_CARE__FLAG, denali->reg + CHIP_ENABLE_DONT_CARE);
+
+	iowrite32(0xffff, denali->reg + SPARE_AREA_MARKER);
+}
+
+int denali_calc_ecc_bytes(int step_size, int strength)
+{
+	/* BCH code.  Denali requires ecc.bytes to be multiple of 2 */
+	return DIV_ROUND_UP(strength * fls(step_size * 8), 16) * 2;
+}
+EXPORT_SYMBOL(denali_calc_ecc_bytes);
+
+static int denali_ecc_setup(struct mtd_info *mtd, struct nand_chip *chip,
+			    struct denali_nand_info *denali)
+{
+	int oobavail = mtd->oobsize - denali->oob_skip_bytes;
+	int ret;
+
+	/*
+	 * If .size and .strength are already set (usually by DT),
+	 * check if they are supported by this controller.
+	 */
+	if (chip->ecc.size && chip->ecc.strength)
+		return nand_check_ecc_caps(chip, denali->ecc_caps, oobavail);
+
+	/*
+	 * We want .size and .strength closest to the chip's requirement
+	 * unless NAND_ECC_MAXIMIZE is requested.
+	 */
+	if (!(chip->ecc.options & NAND_ECC_MAXIMIZE)) {
+		ret = nand_match_ecc_req(chip, denali->ecc_caps, oobavail);
+		if (!ret)
+			return 0;
+	}
+
+	/* Max ECC strength is the last thing we can do */
+	return nand_maximize_ecc(chip, denali->ecc_caps, oobavail);
+}
+
+static int denali_ooblayout_ecc(struct mtd_info *mtd, int section,
+				struct mtd_oob_region *oobregion)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+	struct nand_chip *chip = mtd_to_nand(mtd);
+
+	if (section)
+		return -ERANGE;
+
+	oobregion->offset = denali->oob_skip_bytes;
+	oobregion->length = chip->ecc.total;
+
+	return 0;
+}
+
+static int denali_ooblayout_free(struct mtd_info *mtd, int section,
+				 struct mtd_oob_region *oobregion)
+{
+	struct denali_nand_info *denali = mtd_to_denali(mtd);
+	struct nand_chip *chip = mtd_to_nand(mtd);
+
+	if (section)
+		return -ERANGE;
+
+	oobregion->offset = chip->ecc.total + denali->oob_skip_bytes;
+	oobregion->length = mtd->oobsize - oobregion->offset;
+
+	return 0;
+}
+
+static const struct mtd_ooblayout_ops denali_ooblayout_ops = {
+	.ecc = denali_ooblayout_ecc,
+	.free = denali_ooblayout_free,
+};
+
+static int denali_multidev_fixup(struct denali_nand_info *denali)
+{
+	struct nand_chip *chip = &denali->nand;
+	struct mtd_info *mtd = nand_to_mtd(chip);
+
+	/*
+	 * Support for multi device:
+	 * When the IP configuration is x16 capable and two x8 chips are
+	 * connected in parallel, DEVICES_CONNECTED should be set to 2.
+	 * In this case, the core framework knows nothing about this fact,
+	 * so we should tell it the _logical_ pagesize and anything necessary.
+	 */
+	denali->devs_per_cs = ioread32(denali->reg + DEVICES_CONNECTED);
+
+	/*
+	 * On some SoCs, DEVICES_CONNECTED is not auto-detected.
+	 * For those, DEVICES_CONNECTED is left to 0.  Set 1 if it is the case.
+	 */
+	if (denali->devs_per_cs == 0) {
+		denali->devs_per_cs = 1;
+		iowrite32(1, denali->reg + DEVICES_CONNECTED);
+	}
+
+	if (denali->devs_per_cs == 1)
+		return 0;
+
+	if (denali->devs_per_cs != 2) {
+		dev_err(denali->dev, "unsupported number of devices %d\n",
+			denali->devs_per_cs);
+		return -EINVAL;
+	}
+
+	/* 2 chips in parallel */
+	mtd->size <<= 1;
+	mtd->erasesize <<= 1;
+	mtd->writesize <<= 1;
+	mtd->oobsize <<= 1;
+	chip->chipsize <<= 1;
+	chip->page_shift += 1;
+	chip->phys_erase_shift += 1;
+	chip->bbt_erase_shift += 1;
+	chip->chip_shift += 1;
+	chip->pagemask <<= 1;
+	chip->ecc.size <<= 1;
+	chip->ecc.bytes <<= 1;
+	chip->ecc.strength <<= 1;
+	denali->oob_skip_bytes <<= 1;
+
+	return 0;
+}
+
+int denali_init(struct denali_nand_info *denali)
+{
+	struct nand_chip *chip = &denali->nand;
+	struct mtd_info *mtd = nand_to_mtd(chip);
+	u32 features = ioread32(denali->reg + FEATURES);
+	int ret;
+
+	mtd->dev.parent = denali->dev;
+	denali_hw_init(denali);
+
+	init_completion(&denali->complete);
+	spin_lock_init(&denali->irq_lock);
+
+	denali_clear_irq_all(denali);
+
+	ret = devm_request_irq(denali->dev, denali->irq, denali_isr,
+			       IRQF_SHARED, DENALI_NAND_NAME, denali);
+	if (ret) {
+		dev_err(denali->dev, "Unable to request IRQ\n");
+		return ret;
+	}
+
+	denali_enable_irq(denali);
+	denali_reset_banks(denali);
+
+	denali->active_bank = DENALI_INVALID_BANK;
+
+	nand_set_flash_node(chip, denali->dev->of_node);
+	/* Fallback to the default name if DT did not give "label" property */
+	if (!mtd->name)
+		mtd->name = "denali-nand";
+
+	chip->select_chip = denali_select_chip;
+	chip->read_byte = denali_read_byte;
+	chip->write_byte = denali_write_byte;
+	chip->read_word = denali_read_word;
+	chip->cmd_ctrl = denali_cmd_ctrl;
+	chip->dev_ready = denali_dev_ready;
+	chip->waitfunc = denali_waitfunc;
+
+	if (features & FEATURES__INDEX_ADDR) {
+		denali->host_read = denali_indexed_read;
+		denali->host_write = denali_indexed_write;
+	} else {
+		denali->host_read = denali_direct_read;
+		denali->host_write = denali_direct_write;
+	}
+
+	/* clk rate info is needed for setup_data_interface */
+	if (denali->clk_x_rate)
+		chip->setup_data_interface = denali_setup_data_interface;
+
+	ret = nand_scan_ident(mtd, denali->max_banks, NULL);
+	if (ret)
+		goto disable_irq;
+
+	if (ioread32(denali->reg + FEATURES) & FEATURES__DMA)
+		denali->dma_avail = 1;
+
+	if (denali->dma_avail) {
+		int dma_bit = denali->caps & DENALI_CAP_DMA_64BIT ? 64 : 32;
+
+		ret = dma_set_mask(denali->dev, DMA_BIT_MASK(dma_bit));
+		if (ret) {
+			dev_info(denali->dev,
+				 "Failed to set DMA mask. Disabling DMA.\n");
+			denali->dma_avail = 0;
+		}
+	}
+
+	if (denali->dma_avail) {
+		chip->options |= NAND_USE_BOUNCE_BUFFER;
+		chip->buf_align = 16;
+		if (denali->caps & DENALI_CAP_DMA_64BIT)
+			denali->setup_dma = denali_setup_dma64;
+		else
+			denali->setup_dma = denali_setup_dma32;
+	}
+
+	chip->bbt_options |= NAND_BBT_USE_FLASH;
+	chip->bbt_options |= NAND_BBT_NO_OOB;
+	chip->ecc.mode = NAND_ECC_HW_SYNDROME;
+	chip->options |= NAND_NO_SUBPAGE_WRITE;
+
+	ret = denali_ecc_setup(mtd, chip, denali);
+	if (ret) {
+		dev_err(denali->dev, "Failed to setup ECC settings.\n");
+		goto disable_irq;
+	}
+
+	dev_dbg(denali->dev,
+		"chosen ECC settings: step=%d, strength=%d, bytes=%d\n",
+		chip->ecc.size, chip->ecc.strength, chip->ecc.bytes);
+
+	iowrite32(FIELD_PREP(ECC_CORRECTION__ERASE_THRESHOLD, 1) |
+		  FIELD_PREP(ECC_CORRECTION__VALUE, chip->ecc.strength),
+		  denali->reg + ECC_CORRECTION);
+	iowrite32(mtd->erasesize / mtd->writesize,
+		  denali->reg + PAGES_PER_BLOCK);
+	iowrite32(chip->options & NAND_BUSWIDTH_16 ? 1 : 0,
+		  denali->reg + DEVICE_WIDTH);
+	iowrite32(chip->options & NAND_ROW_ADDR_3 ? 0 : TWO_ROW_ADDR_CYCLES__FLAG,
+		  denali->reg + TWO_ROW_ADDR_CYCLES);
+	iowrite32(mtd->writesize, denali->reg + DEVICE_MAIN_AREA_SIZE);
+	iowrite32(mtd->oobsize, denali->reg + DEVICE_SPARE_AREA_SIZE);
+
+	iowrite32(chip->ecc.size, denali->reg + CFG_DATA_BLOCK_SIZE);
+	iowrite32(chip->ecc.size, denali->reg + CFG_LAST_DATA_BLOCK_SIZE);
+	/* chip->ecc.steps is set by nand_scan_tail(); not available here */
+	iowrite32(mtd->writesize / chip->ecc.size,
+		  denali->reg + CFG_NUM_DATA_BLOCKS);
+
+	mtd_set_ooblayout(mtd, &denali_ooblayout_ops);
+
+	if (chip->options & NAND_BUSWIDTH_16) {
+		chip->read_buf = denali_read_buf16;
+		chip->write_buf = denali_write_buf16;
+	} else {
+		chip->read_buf = denali_read_buf;
+		chip->write_buf = denali_write_buf;
+	}
+	chip->ecc.read_page = denali_read_page;
+	chip->ecc.read_page_raw = denali_read_page_raw;
+	chip->ecc.write_page = denali_write_page;
+	chip->ecc.write_page_raw = denali_write_page_raw;
+	chip->ecc.read_oob = denali_read_oob;
+	chip->ecc.write_oob = denali_write_oob;
+	chip->erase = denali_erase;
+
+	ret = denali_multidev_fixup(denali);
+	if (ret)
+		goto disable_irq;
+
+	/*
+	 * This buffer is DMA-mapped by denali_{read,write}_page_raw.  Do not
+	 * use devm_kmalloc() because the memory allocated by devm_ does not
+	 * guarantee DMA-safe alignment.
+	 */
+	denali->buf = kmalloc(mtd->writesize + mtd->oobsize, GFP_KERNEL);
+	if (!denali->buf) {
+		ret = -ENOMEM;
+		goto disable_irq;
+	}
+
+	ret = nand_scan_tail(mtd);
+	if (ret)
+		goto free_buf;
+
+	ret = mtd_device_register(mtd, NULL, 0);
+	if (ret) {
+		dev_err(denali->dev, "Failed to register MTD: %d\n", ret);
+		goto free_buf;
+	}
+	return 0;
+
+free_buf:
+	kfree(denali->buf);
+disable_irq:
+	denali_disable_irq(denali);
+
+	return ret;
+}
+EXPORT_SYMBOL(denali_init);
+
+void denali_remove(struct denali_nand_info *denali)
+{
+	struct mtd_info *mtd = nand_to_mtd(&denali->nand);
+
+	nand_release(mtd);
+	kfree(denali->buf);
+	denali_disable_irq(denali);
+}
+EXPORT_SYMBOL(denali_remove);