Freescale eLBC FCM NAND driver

This is a driver for the Flash Control Machine of the enhanched Local Bus
Controller found on some Freescale chips (such as the mpc8313 and the
mpc8379).

Signed-off-by: Scott Wood <scottwood@freescale.com>

1 files changed, 759 insertions, 0 deletions

diff --git a/drivers/mtd/nand/fsl_elbc_nand.c b/drivers/mtd/nand/fsl_elbc_nand.c
new file mode 100644
index 000000000..c1644c0f6
--- /dev/null
+++ b/drivers/mtd/nand/fsl_elbc_nand.c
@@ -0,0 +1,759 @@
+/* Freescale Enhanced Local Bus Controller FCM NAND driver
+ *
+ * Copyright (c) 2006-2008 Freescale Semiconductor
+ *
+ * Authors: Nick Spence <nick.spence@freescale.com>,
+ *          Scott Wood <scottwood@freescale.com>
+ *
+ * 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.
+ *
+ * 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; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <common.h>
+#include <malloc.h>
+
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/nand_ecc.h>
+
+#include <asm/io.h>
+#include <asm/errno.h>
+
+#ifdef VERBOSE_DEBUG
+#define DEBUG_ELBC
+#define vdbg(format, arg...) printf("DEBUG: " format, ##arg)
+#else
+#define vdbg(format, arg...) do {} while (0)
+#endif
+
+/* Can't use plain old DEBUG because the linux mtd
+ * headers define it as a macro.
+ */
+#ifdef DEBUG_ELBC
+#define dbg(format, arg...) printf("DEBUG: " format, ##arg)
+#else
+#define dbg(format, arg...) do {} while (0)
+#endif
+
+#define MAX_BANKS 8
+#define ERR_BYTE 0xFF /* Value returned for read bytes when read failed */
+#define FCM_TIMEOUT_MSECS 10 /* Maximum number of mSecs to wait for FCM */
+
+#define LTESR_NAND_MASK (LTESR_FCT | LTESR_PAR | LTESR_CC)
+
+struct fsl_elbc_ctrl;
+
+/* mtd information per set */
+
+struct fsl_elbc_mtd {
+	struct mtd_info mtd;
+	struct nand_chip chip;
+	struct fsl_elbc_ctrl *ctrl;
+
+	struct device *dev;
+	int bank;               /* Chip select bank number           */
+	u8 __iomem *vbase;      /* Chip select base virtual address  */
+	int page_size;          /* NAND page size (0=512, 1=2048)    */
+	unsigned int fmr;       /* FCM Flash Mode Register value     */
+};
+
+/* overview of the fsl elbc controller */
+
+struct fsl_elbc_ctrl {
+	struct nand_hw_control controller;
+	struct fsl_elbc_mtd *chips[MAX_BANKS];
+
+	/* device info */
+	lbus83xx_t *regs;
+	u8 __iomem *addr;        /* Address of assigned FCM buffer        */
+	unsigned int page;       /* Last page written to / read from      */
+	unsigned int read_bytes; /* Number of bytes read during command   */
+	unsigned int column;     /* Saved column from SEQIN               */
+	unsigned int index;      /* Pointer to next byte to 'read'        */
+	unsigned int status;     /* status read from LTESR after last op  */
+	unsigned int mdr;        /* UPM/FCM Data Register value           */
+	unsigned int use_mdr;    /* Non zero if the MDR is to be set      */
+	unsigned int oob;        /* Non zero if operating on OOB data     */
+	uint8_t *oob_poi;        /* Place to write ECC after read back    */
+};
+
+/* These map to the positions used by the FCM hardware ECC generator */
+
+/* Small Page FLASH with FMR[ECCM] = 0 */
+static struct nand_ecclayout fsl_elbc_oob_sp_eccm0 = {
+	.eccbytes = 3,
+	.eccpos = {6, 7, 8},
+	.oobfree = { {0, 5}, {9, 7} },
+	.oobavail = 12,
+};
+
+/* Small Page FLASH with FMR[ECCM] = 1 */
+static struct nand_ecclayout fsl_elbc_oob_sp_eccm1 = {
+	.eccbytes = 3,
+	.eccpos = {8, 9, 10},
+	.oobfree = { {0, 5}, {6, 2}, {11, 5} },
+	.oobavail = 12,
+};
+
+/* Large Page FLASH with FMR[ECCM] = 0 */
+static struct nand_ecclayout fsl_elbc_oob_lp_eccm0 = {
+	.eccbytes = 12,
+	.eccpos = {6, 7, 8, 22, 23, 24, 38, 39, 40, 54, 55, 56},
+	.oobfree = { {1, 5}, {9, 13}, {25, 13}, {41, 13}, {57, 7} },
+	.oobavail = 48,
+};
+
+/* Large Page FLASH with FMR[ECCM] = 1 */
+static struct nand_ecclayout fsl_elbc_oob_lp_eccm1 = {
+	.eccbytes = 12,
+	.eccpos = {8, 9, 10, 24, 25, 26, 40, 41, 42, 56, 57, 58},
+	.oobfree = { {1, 7}, {11, 13}, {27, 13}, {43, 13}, {59, 5} },
+	.oobavail = 48,
+};
+
+/*=================================*/
+
+/*
+ * Set up the FCM hardware block and page address fields, and the fcm
+ * structure addr field to point to the correct FCM buffer in memory
+ */
+static void set_addr(struct mtd_info *mtd, int column, int page_addr, int oob)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_elbc_mtd *priv = chip->priv;
+	struct fsl_elbc_ctrl *ctrl = priv->ctrl;
+	lbus83xx_t *lbc = ctrl->regs;
+	int buf_num;
+
+	ctrl->page = page_addr;
+
+	out_be32(&lbc->fbar,
+	         page_addr >> (chip->phys_erase_shift - chip->page_shift));
+
+	if (priv->page_size) {
+		out_be32(&lbc->fpar,
+		         ((page_addr << FPAR_LP_PI_SHIFT) & FPAR_LP_PI) |
+		         (oob ? FPAR_LP_MS : 0) | column);
+		buf_num = (page_addr & 1) << 2;
+	} else {
+		out_be32(&lbc->fpar,
+		         ((page_addr << FPAR_SP_PI_SHIFT) & FPAR_SP_PI) |
+		         (oob ? FPAR_SP_MS : 0) | column);
+		buf_num = page_addr & 7;
+	}
+
+	ctrl->addr = priv->vbase + buf_num * 1024;
+	ctrl->index = column;
+
+	/* for OOB data point to the second half of the buffer */
+	if (oob)
+		ctrl->index += priv->page_size ? 2048 : 512;
+
+	vdbg("set_addr: bank=%d, ctrl->addr=0x%p (0x%p), "
+	     "index %x, pes %d ps %d\n",
+	     buf_num, ctrl->addr, priv->vbase, ctrl->index,
+	     chip->phys_erase_shift, chip->page_shift);
+}
+
+/*
+ * execute FCM command and wait for it to complete
+ */
+static int fsl_elbc_run_command(struct mtd_info *mtd)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_elbc_mtd *priv = chip->priv;
+	struct fsl_elbc_ctrl *ctrl = priv->ctrl;
+	lbus83xx_t *lbc = ctrl->regs;
+	long long end_tick;
+	u32 ltesr;
+
+	/* Setup the FMR[OP] to execute without write protection */
+	out_be32(&lbc->fmr, priv->fmr | 3);
+	if (ctrl->use_mdr)
+		out_be32(&lbc->mdr, ctrl->mdr);
+
+	vdbg("fsl_elbc_run_command: fmr=%08x fir=%08x fcr=%08x\n",
+	     in_be32(&lbc->fmr), in_be32(&lbc->fir), in_be32(&lbc->fcr));
+	vdbg("fsl_elbc_run_command: fbar=%08x fpar=%08x "
+	     "fbcr=%08x bank=%d\n",
+	     in_be32(&lbc->fbar), in_be32(&lbc->fpar),
+	     in_be32(&lbc->fbcr), priv->bank);
+
+	/* execute special operation */
+	out_be32(&lbc->lsor, priv->bank);
+
+	/* wait for FCM complete flag or timeout */
+	end_tick = usec2ticks(FCM_TIMEOUT_MSECS * 1000) + get_ticks();
+
+	ltesr = 0;
+	while (end_tick > get_ticks()) {
+		ltesr = in_be32(&lbc->ltesr);
+		if (ltesr & LTESR_CC)
+			break;
+	}
+
+	ctrl->status = ltesr & LTESR_NAND_MASK;
+	out_be32(&lbc->ltesr, ctrl->status);
+	out_be32(&lbc->lteatr, 0);
+
+	/* store mdr value in case it was needed */
+	if (ctrl->use_mdr)
+		ctrl->mdr = in_be32(&lbc->mdr);
+
+	ctrl->use_mdr = 0;
+
+	vdbg("fsl_elbc_run_command: stat=%08x mdr=%08x fmr=%08x\n",
+	     ctrl->status, ctrl->mdr, in_be32(&lbc->fmr));
+
+	/* returns 0 on success otherwise non-zero) */
+	return ctrl->status == LTESR_CC ? 0 : -EIO;
+}
+
+static void fsl_elbc_do_read(struct nand_chip *chip, int oob)
+{
+	struct fsl_elbc_mtd *priv = chip->priv;
+	struct fsl_elbc_ctrl *ctrl = priv->ctrl;
+	lbus83xx_t *lbc = ctrl->regs;
+
+	if (priv->page_size) {
+		out_be32(&lbc->fir,
+		         (FIR_OP_CW0 << FIR_OP0_SHIFT) |
+		         (FIR_OP_CA  << FIR_OP1_SHIFT) |
+		         (FIR_OP_PA  << FIR_OP2_SHIFT) |
+		         (FIR_OP_CW1 << FIR_OP3_SHIFT) |
+		         (FIR_OP_RBW << FIR_OP4_SHIFT));
+
+		out_be32(&lbc->fcr, (NAND_CMD_READ0 << FCR_CMD0_SHIFT) |
+		                    (NAND_CMD_READSTART << FCR_CMD1_SHIFT));
+	} else {
+		out_be32(&lbc->fir,
+		         (FIR_OP_CW0 << FIR_OP0_SHIFT) |
+		         (FIR_OP_CA  << FIR_OP1_SHIFT) |
+		         (FIR_OP_PA  << FIR_OP2_SHIFT) |
+		         (FIR_OP_RBW << FIR_OP3_SHIFT));
+
+		if (oob)
+			out_be32(&lbc->fcr,
+			         NAND_CMD_READOOB << FCR_CMD0_SHIFT);
+		else
+			out_be32(&lbc->fcr, NAND_CMD_READ0 << FCR_CMD0_SHIFT);
+	}
+}
+
+/* cmdfunc send commands to the FCM */
+static void fsl_elbc_cmdfunc(struct mtd_info *mtd, unsigned int command,
+                             int column, int page_addr)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_elbc_mtd *priv = chip->priv;
+	struct fsl_elbc_ctrl *ctrl = priv->ctrl;
+	lbus83xx_t *lbc = ctrl->regs;
+
+	ctrl->use_mdr = 0;
+
+	/* clear the read buffer */
+	ctrl->read_bytes = 0;
+	if (command != NAND_CMD_PAGEPROG)
+		ctrl->index = 0;
+
+	switch (command) {
+	/* READ0 and READ1 read the entire buffer to use hardware ECC. */
+	case NAND_CMD_READ1:
+		column += 256;
+
+	/* fall-through */
+	case NAND_CMD_READ0:
+		vdbg("fsl_elbc_cmdfunc: NAND_CMD_READ0, page_addr:"
+		     " 0x%x, column: 0x%x.\n", page_addr, column);
+
+		out_be32(&lbc->fbcr, 0); /* read entire page to enable ECC */
+		set_addr(mtd, 0, page_addr, 0);
+
+		ctrl->read_bytes = mtd->writesize + mtd->oobsize;
+		ctrl->index += column;
+
+		fsl_elbc_do_read(chip, 0);
+		fsl_elbc_run_command(mtd);
+		return;
+
+	/* READOOB reads only the OOB because no ECC is performed. */
+	case NAND_CMD_READOOB:
+		vdbg("fsl_elbc_cmdfunc: NAND_CMD_READOOB, page_addr:"
+		     " 0x%x, column: 0x%x.\n", page_addr, column);
+
+		out_be32(&lbc->fbcr, mtd->oobsize - column);
+		set_addr(mtd, column, page_addr, 1);
+
+		ctrl->read_bytes = mtd->writesize + mtd->oobsize;
+
+		fsl_elbc_do_read(chip, 1);
+		fsl_elbc_run_command(mtd);
+
+		return;
+
+	/* READID must read all 5 possible bytes while CEB is active */
+	case NAND_CMD_READID:
+		vdbg("fsl_elbc_cmdfunc: NAND_CMD_READID.\n");
+
+		out_be32(&lbc->fir, (FIR_OP_CW0 << FIR_OP0_SHIFT) |
+		                    (FIR_OP_UA  << FIR_OP1_SHIFT) |
+		                    (FIR_OP_RBW << FIR_OP2_SHIFT));
+		out_be32(&lbc->fcr, NAND_CMD_READID << FCR_CMD0_SHIFT);
+		/* 5 bytes for manuf, device and exts */
+		out_be32(&lbc->fbcr, 5);
+		ctrl->read_bytes = 5;
+		ctrl->use_mdr = 1;
+		ctrl->mdr = 0;
+
+		set_addr(mtd, 0, 0, 0);
+		fsl_elbc_run_command(mtd);
+		return;
+
+	/* ERASE1 stores the block and page address */
+	case NAND_CMD_ERASE1:
+		vdbg("fsl_elbc_cmdfunc: NAND_CMD_ERASE1, "
+		     "page_addr: 0x%x.\n", page_addr);
+		set_addr(mtd, 0, page_addr, 0);
+		return;
+
+	/* ERASE2 uses the block and page address from ERASE1 */
+	case NAND_CMD_ERASE2:
+		vdbg("fsl_elbc_cmdfunc: NAND_CMD_ERASE2.\n");
+
+		out_be32(&lbc->fir,
+		         (FIR_OP_CW0 << FIR_OP0_SHIFT) |
+		         (FIR_OP_PA  << FIR_OP1_SHIFT) |
+		         (FIR_OP_CM1 << FIR_OP2_SHIFT));
+
+		out_be32(&lbc->fcr,
+		         (NAND_CMD_ERASE1 << FCR_CMD0_SHIFT) |
+		         (NAND_CMD_ERASE2 << FCR_CMD1_SHIFT));
+
+		out_be32(&lbc->fbcr, 0);
+		ctrl->read_bytes = 0;
+
+		fsl_elbc_run_command(mtd);
+		return;
+
+	/* SEQIN sets up the addr buffer and all registers except the length */
+	case NAND_CMD_SEQIN: {
+		u32 fcr;
+		vdbg("fsl_elbc_cmdfunc: NAND_CMD_SEQIN/PAGE_PROG, "
+		     "page_addr: 0x%x, column: 0x%x.\n",
+		     page_addr, column);
+
+		ctrl->column = column;
+		ctrl->oob = 0;
+
+		if (priv->page_size) {
+			fcr = (NAND_CMD_SEQIN << FCR_CMD0_SHIFT) |
+			      (NAND_CMD_PAGEPROG << FCR_CMD1_SHIFT);
+
+			out_be32(&lbc->fir,
+			         (FIR_OP_CW0 << FIR_OP0_SHIFT) |
+			         (FIR_OP_CA  << FIR_OP1_SHIFT) |
+			         (FIR_OP_PA  << FIR_OP2_SHIFT) |
+			         (FIR_OP_WB  << FIR_OP3_SHIFT) |
+			         (FIR_OP_CW1 << FIR_OP4_SHIFT));
+		} else {
+			fcr = (NAND_CMD_PAGEPROG << FCR_CMD1_SHIFT) |
+			      (NAND_CMD_SEQIN << FCR_CMD2_SHIFT);
+
+			out_be32(&lbc->fir,
+			         (FIR_OP_CW0 << FIR_OP0_SHIFT) |
+			         (FIR_OP_CM2 << FIR_OP1_SHIFT) |
+			         (FIR_OP_CA  << FIR_OP2_SHIFT) |
+			         (FIR_OP_PA  << FIR_OP3_SHIFT) |
+			         (FIR_OP_WB  << FIR_OP4_SHIFT) |
+			         (FIR_OP_CW1 << FIR_OP5_SHIFT));
+
+			if (column >= mtd->writesize) {
+				/* OOB area --> READOOB */
+				column -= mtd->writesize;
+				fcr |= NAND_CMD_READOOB << FCR_CMD0_SHIFT;
+				ctrl->oob = 1;
+			} else if (column < 256) {
+				/* First 256 bytes --> READ0 */
+				fcr |= NAND_CMD_READ0 << FCR_CMD0_SHIFT;
+			} else {
+				/* Second 256 bytes --> READ1 */
+				fcr |= NAND_CMD_READ1 << FCR_CMD0_SHIFT;
+			}
+		}
+
+		out_be32(&lbc->fcr, fcr);
+		set_addr(mtd, column, page_addr, ctrl->oob);
+		return;
+	}
+
+	/* PAGEPROG reuses all of the setup from SEQIN and adds the length */
+	case NAND_CMD_PAGEPROG: {
+		int full_page;
+		vdbg("fsl_elbc_cmdfunc: NAND_CMD_PAGEPROG "
+		     "writing %d bytes.\n", ctrl->index);
+
+		/* if the write did not start at 0 or is not a full page
+		 * then set the exact length, otherwise use a full page
+		 * write so the HW generates the ECC.
+		 */
+		if (ctrl->oob || ctrl->column != 0 ||
+		    ctrl->index != mtd->writesize + mtd->oobsize) {
+			out_be32(&lbc->fbcr, ctrl->index);
+			full_page = 0;
+		} else {
+			out_be32(&lbc->fbcr, 0);
+			full_page = 1;
+		}
+
+		fsl_elbc_run_command(mtd);
+
+		/* Read back the page in order to fill in the ECC for the
+		 * caller.  Is this really needed?
+		 */
+		if (full_page && ctrl->oob_poi) {
+			out_be32(&lbc->fbcr, 3);
+			set_addr(mtd, 6, page_addr, 1);
+
+			ctrl->read_bytes = mtd->writesize + 9;
+
+			fsl_elbc_do_read(chip, 1);
+			fsl_elbc_run_command(mtd);
+
+			memcpy_fromio(ctrl->oob_poi + 6,
+			              &ctrl->addr[ctrl->index], 3);
+			ctrl->index += 3;
+		}
+
+		ctrl->oob_poi = NULL;
+		return;
+	}
+
+	/* CMD_STATUS must read the status byte while CEB is active */
+	/* Note - it does not wait for the ready line */
+	case NAND_CMD_STATUS:
+		out_be32(&lbc->fir,
+		         (FIR_OP_CM0 << FIR_OP0_SHIFT) |
+		         (FIR_OP_RBW << FIR_OP1_SHIFT));
+		out_be32(&lbc->fcr, NAND_CMD_STATUS << FCR_CMD0_SHIFT);
+		out_be32(&lbc->fbcr, 1);
+		set_addr(mtd, 0, 0, 0);
+		ctrl->read_bytes = 1;
+
+		fsl_elbc_run_command(mtd);
+
+		/* The chip always seems to report that it is
+		 * write-protected, even when it is not.
+		 */
+		out_8(ctrl->addr, in_8(ctrl->addr) | NAND_STATUS_WP);
+		return;
+
+	/* RESET without waiting for the ready line */
+	case NAND_CMD_RESET:
+		dbg("fsl_elbc_cmdfunc: NAND_CMD_RESET.\n");
+		out_be32(&lbc->fir, FIR_OP_CM0 << FIR_OP0_SHIFT);
+		out_be32(&lbc->fcr, NAND_CMD_RESET << FCR_CMD0_SHIFT);
+		fsl_elbc_run_command(mtd);
+		return;
+
+	default:
+		printf("fsl_elbc_cmdfunc: error, unsupported command 0x%x.\n",
+		        command);
+	}
+}
+
+static void fsl_elbc_select_chip(struct mtd_info *mtd, int chip)
+{
+	/* The hardware does not seem to support multiple
+	 * chips per bank.
+	 */
+}
+
+/*
+ * Write buf to the FCM Controller Data Buffer
+ */
+static void fsl_elbc_write_buf(struct mtd_info *mtd, const u8 *buf, int len)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_elbc_mtd *priv = chip->priv;
+	struct fsl_elbc_ctrl *ctrl = priv->ctrl;
+	unsigned int bufsize = mtd->writesize + mtd->oobsize;
+
+	if (len < 0) {
+		printf("write_buf of %d bytes", len);
+		ctrl->status = 0;
+		return;
+	}
+
+	if ((unsigned int)len > bufsize - ctrl->index) {
+		printf("write_buf beyond end of buffer "
+		       "(%d requested, %u available)\n",
+		       len, bufsize - ctrl->index);
+		len = bufsize - ctrl->index;
+	}
+
+	memcpy_toio(&ctrl->addr[ctrl->index], buf, len);
+	ctrl->index += len;
+}
+
+/*
+ * read a byte from either the FCM hardware buffer if it has any data left
+ * otherwise issue a command to read a single byte.
+ */
+static u8 fsl_elbc_read_byte(struct mtd_info *mtd)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_elbc_mtd *priv = chip->priv;
+	struct fsl_elbc_ctrl *ctrl = priv->ctrl;
+
+	/* If there are still bytes in the FCM, then use the next byte. */
+	if (ctrl->index < ctrl->read_bytes)
+		return in_8(&ctrl->addr[ctrl->index++]);
+
+	printf("read_byte beyond end of buffer\n");
+	return ERR_BYTE;
+}
+
+/*
+ * Read from the FCM Controller Data Buffer
+ */
+static void fsl_elbc_read_buf(struct mtd_info *mtd, u8 *buf, int len)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_elbc_mtd *priv = chip->priv;
+	struct fsl_elbc_ctrl *ctrl = priv->ctrl;
+	int avail;
+
+	if (len < 0)
+		return;
+
+	avail = min((unsigned int)len, ctrl->read_bytes - ctrl->index);
+	memcpy_fromio(buf, &ctrl->addr[ctrl->index], avail);
+	ctrl->index += avail;
+
+	if (len > avail)
+		printf("read_buf beyond end of buffer "
+		       "(%d requested, %d available)\n",
+		       len, avail);
+}
+
+/*
+ * Verify buffer against the FCM Controller Data Buffer
+ */
+static int fsl_elbc_verify_buf(struct mtd_info *mtd,
+                               const u_char *buf, int len)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_elbc_mtd *priv = chip->priv;
+	struct fsl_elbc_ctrl *ctrl = priv->ctrl;
+	int i;
+
+	if (len < 0) {
+		printf("write_buf of %d bytes", len);
+		return -EINVAL;
+	}
+
+	if ((unsigned int)len > ctrl->read_bytes - ctrl->index) {
+		printf("verify_buf beyond end of buffer "
+		       "(%d requested, %u available)\n",
+		       len, ctrl->read_bytes - ctrl->index);
+
+		ctrl->index = ctrl->read_bytes;
+		return -EINVAL;
+	}
+
+	for (i = 0; i < len; i++)
+		if (in_8(&ctrl->addr[ctrl->index + i]) != buf[i])
+			break;
+
+	ctrl->index += len;
+	return i == len && ctrl->status == LTESR_CC ? 0 : -EIO;
+}
+
+/* This function is called after Program and Erase Operations to
+ * check for success or failure.
+ */
+static int fsl_elbc_wait(struct mtd_info *mtd, struct nand_chip *chip)
+{
+	struct fsl_elbc_mtd *priv = chip->priv;
+	struct fsl_elbc_ctrl *ctrl = priv->ctrl;
+	lbus83xx_t *lbc = ctrl->regs;
+
+	if (ctrl->status != LTESR_CC)
+		return NAND_STATUS_FAIL;
+
+	/* Use READ_STATUS command, but wait for the device to be ready */
+	ctrl->use_mdr = 0;
+	out_be32(&lbc->fir,
+	         (FIR_OP_CW0 << FIR_OP0_SHIFT) |
+	         (FIR_OP_RBW << FIR_OP1_SHIFT));
+	out_be32(&lbc->fcr, NAND_CMD_STATUS << FCR_CMD0_SHIFT);
+	out_be32(&lbc->fbcr, 1);
+	set_addr(mtd, 0, 0, 0);
+	ctrl->read_bytes = 1;
+
+	fsl_elbc_run_command(mtd);
+
+	if (ctrl->status != LTESR_CC)
+		return NAND_STATUS_FAIL;
+
+	/* The chip always seems to report that it is
+	 * write-protected, even when it is not.
+	 */
+	out_8(ctrl->addr, in_8(ctrl->addr) | NAND_STATUS_WP);
+	return fsl_elbc_read_byte(mtd);
+}
+
+static int fsl_elbc_read_page(struct mtd_info *mtd,
+                              struct nand_chip *chip,
+                              uint8_t *buf)
+{
+	fsl_elbc_read_buf(mtd, buf, mtd->writesize);
+	fsl_elbc_read_buf(mtd, chip->oob_poi, mtd->oobsize);
+
+	if (fsl_elbc_wait(mtd, chip) & NAND_STATUS_FAIL)
+		mtd->ecc_stats.failed++;
+
+	return 0;
+}
+
+/* ECC will be calculated automatically, and errors will be detected in
+ * waitfunc.
+ */
+static void fsl_elbc_write_page(struct mtd_info *mtd,
+                                struct nand_chip *chip,
+                                const uint8_t *buf)
+{
+	struct fsl_elbc_mtd *priv = chip->priv;
+	struct fsl_elbc_ctrl *ctrl = priv->ctrl;
+
+	fsl_elbc_write_buf(mtd, buf, mtd->writesize);
+	fsl_elbc_write_buf(mtd, chip->oob_poi, mtd->oobsize);
+
+	ctrl->oob_poi = chip->oob_poi;
+}
+
+static struct fsl_elbc_ctrl *elbc_ctrl;
+
+static void fsl_elbc_ctrl_init(void)
+{
+	immap_t *im = (immap_t *)CFG_IMMR;
+
+	elbc_ctrl = kzalloc(sizeof(*elbc_ctrl), GFP_KERNEL);
+	if (!elbc_ctrl)
+		return;
+
+	elbc_ctrl->regs = &im->lbus;
+
+	/* clear event registers */
+	out_be32(&elbc_ctrl->regs->ltesr, LTESR_NAND_MASK);
+	out_be32(&elbc_ctrl->regs->lteatr, 0);
+
+	/* Enable interrupts for any detected events */
+	out_be32(&elbc_ctrl->regs->lteir, LTESR_NAND_MASK);
+
+	elbc_ctrl->read_bytes = 0;
+	elbc_ctrl->index = 0;
+	elbc_ctrl->addr = NULL;
+}
+
+int board_nand_init(struct nand_chip *nand)
+{
+	struct fsl_elbc_mtd *priv;
+	uint32_t br, or;
+
+	if (!elbc_ctrl) {
+		fsl_elbc_ctrl_init();
+		if (!elbc_ctrl)
+			return -1;
+	}
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->ctrl = elbc_ctrl;
+	priv->vbase = nand->IO_ADDR_R;
+
+	/* Find which chip select it is connected to.  It'd be nice
+	 * if we could pass more than one datum to the NAND driver...
+	 */
+	for (priv->bank = 0; priv->bank < MAX_BANKS; priv->bank++) {
+		br = in_be32(&elbc_ctrl->regs->bank[priv->bank].br);
+		or = in_be32(&elbc_ctrl->regs->bank[priv->bank].or);
+
+		if ((br & BR_V) && (br & BR_MSEL) == BR_MS_FCM &&
+		    (br & or & BR_BA) == (phys_addr_t)nand->IO_ADDR_R)
+			break;
+	}
+
+	if (priv->bank >= MAX_BANKS) {
+		printf("fsl_elbc_nand: address did not match any "
+		       "chip selects\n");
+		return -ENODEV;
+	}
+
+	elbc_ctrl->chips[priv->bank] = priv;
+
+	/* fill in nand_chip structure */
+	/* set up function call table */
+	nand->read_byte = fsl_elbc_read_byte;
+	nand->write_buf = fsl_elbc_write_buf;
+	nand->read_buf = fsl_elbc_read_buf;
+	nand->verify_buf = fsl_elbc_verify_buf;
+	nand->select_chip = fsl_elbc_select_chip;
+	nand->cmdfunc = fsl_elbc_cmdfunc;
+	nand->waitfunc = fsl_elbc_wait;
+
+	/* set up nand options */
+	nand->options = NAND_NO_READRDY | NAND_NO_AUTOINCR;
+
+	nand->controller = &elbc_ctrl->controller;
+	nand->priv = priv;
+
+	nand->ecc.read_page = fsl_elbc_read_page;
+	nand->ecc.write_page = fsl_elbc_write_page;
+
+	/* If CS Base Register selects full hardware ECC then use it */
+	if ((br & BR_DECC) == BR_DECC_CHK_GEN) {
+		nand->ecc.mode = NAND_ECC_HW;
+
+		nand->ecc.layout = (priv->fmr & FMR_ECCM) ?
+		                   &fsl_elbc_oob_sp_eccm1 :
+		                   &fsl_elbc_oob_sp_eccm0;
+
+		nand->ecc.size = 512;
+		nand->ecc.bytes = 3;
+		nand->ecc.steps = 1;
+	} else {
+		/* otherwise fall back to default software ECC */
+		nand->ecc.mode = NAND_ECC_SOFT;
+	}
+
+	priv->fmr = (15 << FMR_CWTO_SHIFT) | (2 << FMR_AL_SHIFT);
+
+	/* adjust Option Register and ECC to match Flash page size */
+	if (or & OR_FCM_PGS) {
+		priv->page_size = 1;
+
+		/* adjust ecc setup if needed */
+		if ((br & BR_DECC) == BR_DECC_CHK_GEN) {
+			nand->ecc.steps = 4;
+			nand->ecc.layout = (priv->fmr & FMR_ECCM) ?
+			                   &fsl_elbc_oob_lp_eccm1 :
+			                   &fsl_elbc_oob_lp_eccm0;
+		}
+	}
+
+	return 0;
+}