nand: Freescale Integrated Flash Controller NAND support

Add NAND support (including spl) on IFC, such as is found on the p1010.

Note that using hardware ECC on IFC with small-page NAND (which is what
comes on the p1010rdb reference board) means there will be insufficient
OOB space for JFFS2, since IFC does not support 1-bit ECC.  UBI should
work, as it does not use OOB for anything but ECC.

When hardware ECC is not enabled in CSOR, software ECC is now used.

Signed-off-by: Dipen Dudhat <Dipen.Dudhat@freescale.com>
[scottwood@freescale.com: ECC rework and misc fixes]
Signed-off-by: Scott Wood <scottwood@freescale.com>
diff --git a/drivers/mtd/nand/fsl_ifc_nand.c b/drivers/mtd/nand/fsl_ifc_nand.c
new file mode 100644
index 0000000..b3f3c3c
--- /dev/null
+++ b/drivers/mtd/nand/fsl_ifc_nand.c
@@ -0,0 +1,850 @@
+/* Integrated Flash Controller NAND Machine Driver
+ *
+ * Copyright (c) 2011 Freescale Semiconductor, Inc
+ *
+ * Authors: Dipen Dudhat <Dipen.Dudhat@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>
+#include <asm/fsl_ifc.h>
+
+#define MAX_BANKS	4
+#define ERR_BYTE	0xFF /* Value returned for read bytes
+				when read failed */
+#define IFC_TIMEOUT_MSECS 10 /* Maximum number of mSecs to wait for IFC
+				NAND Machine */
+
+struct fsl_ifc_ctrl;
+
+/* mtd information per set */
+struct fsl_ifc_mtd {
+	struct mtd_info mtd;
+	struct nand_chip chip;
+	struct fsl_ifc_ctrl *ctrl;
+
+	struct device *dev;
+	int bank;               /* Chip select bank number                */
+	unsigned int bufnum_mask; /* bufnum = page & bufnum_mask */
+	u8 __iomem *vbase;      /* Chip select base virtual address       */
+};
+
+/* overview of the fsl ifc controller */
+struct fsl_ifc_ctrl {
+	struct nand_hw_control controller;
+	struct fsl_ifc_mtd *chips[MAX_BANKS];
+
+	/* device info */
+	struct fsl_ifc *regs;
+	uint8_t __iomem *addr;   /* Address of assigned IFC buffer        */
+	unsigned int cs_nand;    /* On which chipsel NAND is connected	  */
+	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 NEESR after last op  */
+	unsigned int oob;        /* Non zero if operating on OOB data     */
+	unsigned int eccread;    /* Non zero for a full-page ECC read     */
+};
+
+static struct fsl_ifc_ctrl *ifc_ctrl;
+
+/* 512-byte page with 4-bit ECC, 8-bit */
+static struct nand_ecclayout oob_512_8bit_ecc4 = {
+	.eccbytes = 8,
+	.eccpos = {8, 9, 10, 11, 12, 13, 14, 15},
+	.oobfree = { {0, 5}, {6, 2} },
+};
+
+/* 512-byte page with 4-bit ECC, 16-bit */
+static struct nand_ecclayout oob_512_16bit_ecc4 = {
+	.eccbytes = 8,
+	.eccpos = {8, 9, 10, 11, 12, 13, 14, 15},
+	.oobfree = { {2, 6}, },
+};
+
+/* 2048-byte page size with 4-bit ECC */
+static struct nand_ecclayout oob_2048_ecc4 = {
+	.eccbytes = 32,
+	.eccpos = {
+		8, 9, 10, 11, 12, 13, 14, 15,
+		16, 17, 18, 19, 20, 21, 22, 23,
+		24, 25, 26, 27, 28, 29, 30, 31,
+		32, 33, 34, 35, 36, 37, 38, 39,
+	},
+	.oobfree = { {2, 6}, {40, 24} },
+};
+
+/* 4096-byte page size with 4-bit ECC */
+static struct nand_ecclayout oob_4096_ecc4 = {
+	.eccbytes = 64,
+	.eccpos = {
+		8, 9, 10, 11, 12, 13, 14, 15,
+		16, 17, 18, 19, 20, 21, 22, 23,
+		24, 25, 26, 27, 28, 29, 30, 31,
+		32, 33, 34, 35, 36, 37, 38, 39,
+		40, 41, 42, 43, 44, 45, 46, 47,
+		48, 49, 50, 51, 52, 53, 54, 55,
+		56, 57, 58, 59, 60, 61, 62, 63,
+		64, 65, 66, 67, 68, 69, 70, 71,
+	},
+	.oobfree = { {2, 6}, {72, 56} },
+};
+
+/* 4096-byte page size with 8-bit ECC -- requires 218-byte OOB */
+static struct nand_ecclayout oob_4096_ecc8 = {
+	.eccbytes = 128,
+	.eccpos = {
+		8, 9, 10, 11, 12, 13, 14, 15,
+		16, 17, 18, 19, 20, 21, 22, 23,
+		24, 25, 26, 27, 28, 29, 30, 31,
+		32, 33, 34, 35, 36, 37, 38, 39,
+		40, 41, 42, 43, 44, 45, 46, 47,
+		48, 49, 50, 51, 52, 53, 54, 55,
+		56, 57, 58, 59, 60, 61, 62, 63,
+		64, 65, 66, 67, 68, 69, 70, 71,
+		72, 73, 74, 75, 76, 77, 78, 79,
+		80, 81, 82, 83, 84, 85, 86, 87,
+		88, 89, 90, 91, 92, 93, 94, 95,
+		96, 97, 98, 99, 100, 101, 102, 103,
+		104, 105, 106, 107, 108, 109, 110, 111,
+		112, 113, 114, 115, 116, 117, 118, 119,
+		120, 121, 122, 123, 124, 125, 126, 127,
+		128, 129, 130, 131, 132, 133, 134, 135,
+	},
+	.oobfree = { {2, 6}, {136, 82} },
+};
+
+
+/*
+ * Generic flash bbt descriptors
+ */
+static u8 bbt_pattern[] = {'B', 'b', 't', '0' };
+static u8 mirror_pattern[] = {'1', 't', 'b', 'B' };
+
+static struct nand_bbt_descr bbt_main_descr = {
+	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE |
+		   NAND_BBT_2BIT | NAND_BBT_VERSION,
+	.offs =	2, /* 0 on 8-bit small page */
+	.len = 4,
+	.veroffs = 6,
+	.maxblocks = 4,
+	.pattern = bbt_pattern,
+};
+
+static struct nand_bbt_descr bbt_mirror_descr = {
+	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE |
+		   NAND_BBT_2BIT | NAND_BBT_VERSION,
+	.offs =	2, /* 0 on 8-bit small page */
+	.len = 4,
+	.veroffs = 6,
+	.maxblocks = 4,
+	.pattern = mirror_pattern,
+};
+
+/*
+ * Set up the IFC hardware block and page address fields, and the ifc nand
+ * structure addr field to point to the correct IFC 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_ifc_mtd *priv = chip->priv;
+	struct fsl_ifc_ctrl *ctrl = priv->ctrl;
+	struct fsl_ifc *ifc = ctrl->regs;
+	int buf_num;
+
+	ctrl->page = page_addr;
+
+	/* Program ROW0/COL0 */
+	out_be32(&ifc->ifc_nand.row0, page_addr);
+	out_be32(&ifc->ifc_nand.col0, (oob ? IFC_NAND_COL_MS : 0) | column);
+
+	buf_num = page_addr & priv->bufnum_mask;
+
+	ctrl->addr = priv->vbase + buf_num * (mtd->writesize * 2);
+	ctrl->index = column;
+
+	/* for OOB data point to the second half of the buffer */
+	if (oob)
+		ctrl->index += mtd->writesize;
+}
+
+static int is_blank(struct mtd_info *mtd, struct fsl_ifc_ctrl *ctrl,
+		    unsigned int bufnum)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_ifc_mtd *priv = chip->priv;
+	u8 __iomem *addr = priv->vbase + bufnum * (mtd->writesize * 2);
+	u32 __iomem *main = (u32 *)addr;
+	u8 __iomem *oob = addr + mtd->writesize;
+	int i;
+
+	for (i = 0; i < mtd->writesize / 4; i++) {
+		if (__raw_readl(&main[i]) != 0xffffffff)
+			return 0;
+	}
+
+	for (i = 0; i < chip->ecc.layout->eccbytes; i++) {
+		int pos = chip->ecc.layout->eccpos[i];
+
+		if (__raw_readb(&oob[pos]) != 0xff)
+			return 0;
+	}
+
+	return 1;
+}
+
+/* returns nonzero if entire page is blank */
+static int check_read_ecc(struct mtd_info *mtd, struct fsl_ifc_ctrl *ctrl,
+			  u32 *eccstat, unsigned int bufnum)
+{
+	u32 reg = eccstat[bufnum / 4];
+	int errors = (reg >> ((3 - bufnum % 4) * 8)) & 15;
+
+	if (errors == 15) { /* uncorrectable */
+		/* Blank pages fail hw ECC checks */
+		if (is_blank(mtd, ctrl, bufnum))
+			return 1;
+
+		/*
+		 * We disable ECCER reporting in hardware due to
+		 * erratum IFC-A002770 -- so report it now if we
+		 * see an uncorrectable error in ECCSTAT.
+		 */
+		ctrl->status |= IFC_NAND_EVTER_STAT_ECCER;
+	} else if (errors > 0) {
+		mtd->ecc_stats.corrected += errors;
+	}
+
+	return 0;
+}
+
+/*
+ * execute IFC NAND command and wait for it to complete
+ */
+static int fsl_ifc_run_command(struct mtd_info *mtd)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_ifc_mtd *priv = chip->priv;
+	struct fsl_ifc_ctrl *ctrl = priv->ctrl;
+	struct fsl_ifc *ifc = ctrl->regs;
+	long long end_tick;
+	u32 eccstat[4];
+	int i;
+
+	/* set the chip select for NAND Transaction */
+	out_be32(&ifc->ifc_nand.nand_csel, ifc_ctrl->cs_nand);
+
+	/* start read/write seq */
+	out_be32(&ifc->ifc_nand.nandseq_strt,
+		 IFC_NAND_SEQ_STRT_FIR_STRT);
+
+	/* wait for NAND Machine complete flag or timeout */
+	end_tick = usec2ticks(IFC_TIMEOUT_MSECS * 1000) + get_ticks();
+
+	while (end_tick > get_ticks()) {
+		ctrl->status = in_be32(&ifc->ifc_nand.nand_evter_stat);
+
+		if (ctrl->status & IFC_NAND_EVTER_STAT_OPC)
+			break;
+	}
+
+	out_be32(&ifc->ifc_nand.nand_evter_stat, ctrl->status);
+
+	if (ctrl->status & IFC_NAND_EVTER_STAT_FTOER)
+		printf("%s: Flash Time Out Error\n", __func__);
+	if (ctrl->status & IFC_NAND_EVTER_STAT_WPER)
+		printf("%s: Write Protect Error\n", __func__);
+
+	if (ctrl->eccread) {
+		int bufperpage = mtd->writesize / 512;
+		int bufnum = (ctrl->page & priv->bufnum_mask) * bufperpage;
+		int bufnum_end = bufnum + bufperpage - 1;
+
+		for (i = bufnum / 4; i <= bufnum_end / 4; i++)
+			eccstat[i] = in_be32(&ifc->ifc_nand.nand_eccstat[i]);
+
+		for (i = bufnum; i <= bufnum_end; i++) {
+			if (check_read_ecc(mtd, ctrl, eccstat, i))
+				break;
+		}
+
+		ctrl->eccread = 0;
+	}
+
+	/* returns 0 on success otherwise non-zero) */
+	return ctrl->status == IFC_NAND_EVTER_STAT_OPC ? 0 : -EIO;
+}
+
+static void fsl_ifc_do_read(struct nand_chip *chip,
+			    int oob,
+			    struct mtd_info *mtd)
+{
+	struct fsl_ifc_mtd *priv = chip->priv;
+	struct fsl_ifc_ctrl *ctrl = priv->ctrl;
+	struct fsl_ifc *ifc = ctrl->regs;
+
+	/* Program FIR/IFC_NAND_FCR0 for Small/Large page */
+	if (mtd->writesize > 512) {
+		out_be32(&ifc->ifc_nand.nand_fir0,
+			 (IFC_FIR_OP_CW0 << IFC_NAND_FIR0_OP0_SHIFT) |
+			 (IFC_FIR_OP_CA0 << IFC_NAND_FIR0_OP1_SHIFT) |
+			 (IFC_FIR_OP_RA0 << IFC_NAND_FIR0_OP2_SHIFT) |
+			 (IFC_FIR_OP_CMD1 << IFC_NAND_FIR0_OP3_SHIFT) |
+			 (IFC_FIR_OP_RBCD << IFC_NAND_FIR0_OP4_SHIFT));
+		out_be32(&ifc->ifc_nand.nand_fir1, 0x0);
+
+		out_be32(&ifc->ifc_nand.nand_fcr0,
+			(NAND_CMD_READ0 << IFC_NAND_FCR0_CMD0_SHIFT) |
+			(NAND_CMD_READSTART << IFC_NAND_FCR0_CMD1_SHIFT));
+	} else {
+		out_be32(&ifc->ifc_nand.nand_fir0,
+			 (IFC_FIR_OP_CW0 << IFC_NAND_FIR0_OP0_SHIFT) |
+			 (IFC_FIR_OP_CA0 << IFC_NAND_FIR0_OP1_SHIFT) |
+			 (IFC_FIR_OP_RA0  << IFC_NAND_FIR0_OP2_SHIFT) |
+			 (IFC_FIR_OP_RBCD << IFC_NAND_FIR0_OP3_SHIFT));
+
+		if (oob)
+			out_be32(&ifc->ifc_nand.nand_fcr0,
+				 NAND_CMD_READOOB << IFC_NAND_FCR0_CMD0_SHIFT);
+		else
+			out_be32(&ifc->ifc_nand.nand_fcr0,
+				NAND_CMD_READ0 << IFC_NAND_FCR0_CMD0_SHIFT);
+	}
+}
+
+/* cmdfunc send commands to the IFC NAND Machine */
+static void fsl_ifc_cmdfunc(struct mtd_info *mtd, unsigned int command,
+			     int column, int page_addr)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_ifc_mtd *priv = chip->priv;
+	struct fsl_ifc_ctrl *ctrl = priv->ctrl;
+	struct fsl_ifc *ifc = ctrl->regs;
+
+	/* clear the read buffer */
+	ctrl->read_bytes = 0;
+	if (command != NAND_CMD_PAGEPROG)
+		ctrl->index = 0;
+
+	switch (command) {
+	/* READ0 read the entire buffer to use hardware ECC. */
+	case NAND_CMD_READ0: {
+		out_be32(&ifc->ifc_nand.nand_fbcr, 0);
+		set_addr(mtd, 0, page_addr, 0);
+
+		ctrl->read_bytes = mtd->writesize + mtd->oobsize;
+		ctrl->index += column;
+
+		if (chip->ecc.mode == NAND_ECC_HW)
+			ctrl->eccread = 1;
+
+		fsl_ifc_do_read(chip, 0, mtd);
+		fsl_ifc_run_command(mtd);
+		return;
+	}
+
+	/* READOOB reads only the OOB because no ECC is performed. */
+	case NAND_CMD_READOOB:
+		out_be32(&ifc->ifc_nand.nand_fbcr, mtd->oobsize - column);
+		set_addr(mtd, column, page_addr, 1);
+
+		ctrl->read_bytes = mtd->writesize + mtd->oobsize;
+
+		fsl_ifc_do_read(chip, 1, mtd);
+		fsl_ifc_run_command(mtd);
+
+		return;
+
+	/* READID must read all possible bytes while CEB is active */
+	case NAND_CMD_READID:
+		out_be32(&ifc->ifc_nand.nand_fir0,
+				(IFC_FIR_OP_CMD0 << IFC_NAND_FIR0_OP0_SHIFT) |
+				(IFC_FIR_OP_UA  << IFC_NAND_FIR0_OP1_SHIFT) |
+				(IFC_FIR_OP_RB << IFC_NAND_FIR0_OP2_SHIFT));
+		out_be32(&ifc->ifc_nand.nand_fcr0,
+				NAND_CMD_READID << IFC_NAND_FCR0_CMD0_SHIFT);
+		/* 4 bytes for manuf, device and exts */
+		out_be32(&ifc->ifc_nand.nand_fbcr, 4);
+		ctrl->read_bytes = 4;
+
+		set_addr(mtd, 0, 0, 0);
+		fsl_ifc_run_command(mtd);
+		return;
+
+	/* ERASE1 stores the block and page address */
+	case NAND_CMD_ERASE1:
+		set_addr(mtd, 0, page_addr, 0);
+		return;
+
+	/* ERASE2 uses the block and page address from ERASE1 */
+	case NAND_CMD_ERASE2:
+		out_be32(&ifc->ifc_nand.nand_fir0,
+			 (IFC_FIR_OP_CW0 << IFC_NAND_FIR0_OP0_SHIFT) |
+			 (IFC_FIR_OP_RA0 << IFC_NAND_FIR0_OP1_SHIFT) |
+			 (IFC_FIR_OP_CMD1 << IFC_NAND_FIR0_OP2_SHIFT));
+
+		out_be32(&ifc->ifc_nand.nand_fcr0,
+			 (NAND_CMD_ERASE1 << IFC_NAND_FCR0_CMD0_SHIFT) |
+			 (NAND_CMD_ERASE2 << IFC_NAND_FCR0_CMD1_SHIFT));
+
+		out_be32(&ifc->ifc_nand.nand_fbcr, 0);
+		ctrl->read_bytes = 0;
+		fsl_ifc_run_command(mtd);
+		return;
+
+	/* SEQIN sets up the addr buffer and all registers except the length */
+	case NAND_CMD_SEQIN: {
+		u32 nand_fcr0;
+		ctrl->column = column;
+		ctrl->oob = 0;
+
+		if (mtd->writesize > 512) {
+			nand_fcr0 =
+				(NAND_CMD_SEQIN << IFC_NAND_FCR0_CMD0_SHIFT) |
+				(NAND_CMD_PAGEPROG << IFC_NAND_FCR0_CMD1_SHIFT);
+
+			out_be32(&ifc->ifc_nand.nand_fir0,
+				 (IFC_FIR_OP_CW0 << IFC_NAND_FIR0_OP0_SHIFT) |
+				 (IFC_FIR_OP_CA0 << IFC_NAND_FIR0_OP1_SHIFT) |
+				 (IFC_FIR_OP_RA0 << IFC_NAND_FIR0_OP2_SHIFT) |
+				 (IFC_FIR_OP_WBCD  << IFC_NAND_FIR0_OP3_SHIFT) |
+				 (IFC_FIR_OP_CW1 << IFC_NAND_FIR0_OP4_SHIFT));
+			out_be32(&ifc->ifc_nand.nand_fir1, 0);
+		} else {
+			nand_fcr0 = ((NAND_CMD_PAGEPROG <<
+					IFC_NAND_FCR0_CMD1_SHIFT) |
+				    (NAND_CMD_SEQIN <<
+					IFC_NAND_FCR0_CMD2_SHIFT));
+
+			out_be32(&ifc->ifc_nand.nand_fir0,
+				 (IFC_FIR_OP_CW0 << IFC_NAND_FIR0_OP0_SHIFT) |
+				 (IFC_FIR_OP_CMD2 << IFC_NAND_FIR0_OP1_SHIFT) |
+				 (IFC_FIR_OP_CA0 << IFC_NAND_FIR0_OP2_SHIFT) |
+				 (IFC_FIR_OP_RA0 << IFC_NAND_FIR0_OP3_SHIFT) |
+				 (IFC_FIR_OP_WBCD << IFC_NAND_FIR0_OP4_SHIFT));
+			out_be32(&ifc->ifc_nand.nand_fir1,
+				 (IFC_FIR_OP_CW1 << IFC_NAND_FIR1_OP5_SHIFT));
+
+			if (column >= mtd->writesize) {
+				/* OOB area --> READOOB */
+				column -= mtd->writesize;
+				nand_fcr0 |= NAND_CMD_READOOB <<
+						IFC_NAND_FCR0_CMD0_SHIFT;
+				ctrl->oob = 1;
+			} else if (column < 256) {
+				/* First 256 bytes --> READ0 */
+				nand_fcr0 |= NAND_CMD_READ0 << FCR_CMD0_SHIFT;
+			} else {
+				/* Second 256 bytes --> READ1 */
+				nand_fcr0 |= NAND_CMD_READ1 << FCR_CMD0_SHIFT;
+			}
+		}
+
+		out_be32(&ifc->ifc_nand.nand_fcr0, nand_fcr0);
+		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:
+		if (ctrl->oob)
+			out_be32(&ifc->ifc_nand.nand_fbcr, ctrl->index);
+		else
+			out_be32(&ifc->ifc_nand.nand_fbcr, 0);
+
+		fsl_ifc_run_command(mtd);
+		return;
+
+	case NAND_CMD_STATUS:
+		out_be32(&ifc->ifc_nand.nand_fir0,
+				(IFC_FIR_OP_CW0 << IFC_NAND_FIR0_OP0_SHIFT) |
+				(IFC_FIR_OP_RB << IFC_NAND_FIR0_OP1_SHIFT));
+		out_be32(&ifc->ifc_nand.nand_fcr0,
+				NAND_CMD_STATUS << IFC_NAND_FCR0_CMD0_SHIFT);
+		out_be32(&ifc->ifc_nand.nand_fbcr, 1);
+		set_addr(mtd, 0, 0, 0);
+		ctrl->read_bytes = 1;
+
+		fsl_ifc_run_command(mtd);
+
+		/* Chip sometimes reporting write protect even when it's not */
+		out_8(ctrl->addr, in_8(ctrl->addr) | NAND_STATUS_WP);
+		return;
+
+	case NAND_CMD_RESET:
+		out_be32(&ifc->ifc_nand.nand_fir0,
+				IFC_FIR_OP_CW0 << IFC_NAND_FIR0_OP0_SHIFT);
+		out_be32(&ifc->ifc_nand.nand_fcr0,
+				NAND_CMD_RESET << IFC_NAND_FCR0_CMD0_SHIFT);
+		fsl_ifc_run_command(mtd);
+		return;
+
+	default:
+		printf("%s: error, unsupported command 0x%x.\n",
+			__func__, command);
+	}
+}
+
+/*
+ * Write buf to the IFC NAND Controller Data Buffer
+ */
+static void fsl_ifc_write_buf(struct mtd_info *mtd, const u8 *buf, int len)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_ifc_mtd *priv = chip->priv;
+	struct fsl_ifc_ctrl *ctrl = priv->ctrl;
+	unsigned int bufsize = mtd->writesize + mtd->oobsize;
+
+	if (len <= 0) {
+		printf("%s of %d bytes", __func__, len);
+		ctrl->status = 0;
+		return;
+	}
+
+	if ((unsigned int)len > bufsize - ctrl->index) {
+		printf("%s beyond end of buffer "
+		       "(%d requested, %u available)\n",
+			__func__, 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 IFC hardware buffer if it has any data left
+ * otherwise issue a command to read a single byte.
+ */
+static u8 fsl_ifc_read_byte(struct mtd_info *mtd)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_ifc_mtd *priv = chip->priv;
+	struct fsl_ifc_ctrl *ctrl = priv->ctrl;
+
+	/* If there are still bytes in the IFC buffer, then use the
+	 * next byte. */
+	if (ctrl->index < ctrl->read_bytes)
+		return in_8(&ctrl->addr[ctrl->index++]);
+
+	printf("%s beyond end of buffer\n", __func__);
+	return ERR_BYTE;
+}
+
+/*
+ * Read two bytes from the IFC hardware buffer
+ * read function for 16-bit buswith
+ */
+static uint8_t fsl_ifc_read_byte16(struct mtd_info *mtd)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_ifc_mtd *priv = chip->priv;
+	struct fsl_ifc_ctrl *ctrl = priv->ctrl;
+	uint16_t data;
+
+	/*
+	 * If there are still bytes in the IFC buffer, then use the
+	 * next byte.
+	 */
+	if (ctrl->index < ctrl->read_bytes) {
+		data = in_be16((uint16_t *)&ctrl->
+					addr[ctrl->index]);
+		ctrl->index += 2;
+		return (uint8_t)data;
+	}
+
+	printf("%s beyond end of buffer\n", __func__);
+	return ERR_BYTE;
+}
+
+/*
+ * Read from the IFC Controller Data Buffer
+ */
+static void fsl_ifc_read_buf(struct mtd_info *mtd, u8 *buf, int len)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_ifc_mtd *priv = chip->priv;
+	struct fsl_ifc_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("%s beyond end of buffer "
+		       "(%d requested, %d available)\n",
+		       __func__, len, avail);
+}
+
+/*
+ * Verify buffer against the IFC Controller Data Buffer
+ */
+static int fsl_ifc_verify_buf(struct mtd_info *mtd,
+			       const u_char *buf, int len)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_ifc_mtd *priv = chip->priv;
+	struct fsl_ifc_ctrl *ctrl = priv->ctrl;
+	int i;
+
+	if (len < 0) {
+		printf("%s of %d bytes", __func__, len);
+		return -EINVAL;
+	}
+
+	if ((unsigned int)len > ctrl->read_bytes - ctrl->index) {
+		printf("%s beyond end of buffer "
+		       "(%d requested, %u available)\n",
+		       __func__, 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 == IFC_NAND_EVTER_STAT_OPC ? 0 : -EIO;
+}
+
+/* This function is called after Program and Erase Operations to
+ * check for success or failure.
+ */
+static int fsl_ifc_wait(struct mtd_info *mtd, struct nand_chip *chip)
+{
+	struct fsl_ifc_mtd *priv = chip->priv;
+	struct fsl_ifc_ctrl *ctrl = priv->ctrl;
+	struct fsl_ifc *ifc = ctrl->regs;
+	u32 nand_fsr;
+
+	if (ctrl->status != IFC_NAND_EVTER_STAT_OPC)
+		return NAND_STATUS_FAIL;
+
+	/* Use READ_STATUS command, but wait for the device to be ready */
+	out_be32(&ifc->ifc_nand.nand_fir0,
+		 (IFC_FIR_OP_CW0 << IFC_NAND_FIR0_OP0_SHIFT) |
+		 (IFC_FIR_OP_RDSTAT << IFC_NAND_FIR0_OP1_SHIFT));
+	out_be32(&ifc->ifc_nand.nand_fcr0, NAND_CMD_STATUS <<
+			IFC_NAND_FCR0_CMD0_SHIFT);
+	out_be32(&ifc->ifc_nand.nand_fbcr, 1);
+	set_addr(mtd, 0, 0, 0);
+	ctrl->read_bytes = 1;
+
+	fsl_ifc_run_command(mtd);
+
+	if (ctrl->status != IFC_NAND_EVTER_STAT_OPC)
+		return NAND_STATUS_FAIL;
+
+	nand_fsr = in_be32(&ifc->ifc_nand.nand_fsr);
+
+	/* Chip sometimes reporting write protect even when it's not */
+	nand_fsr = nand_fsr | NAND_STATUS_WP;
+	return nand_fsr;
+}
+
+static int fsl_ifc_read_page(struct mtd_info *mtd,
+			      struct nand_chip *chip,
+			      uint8_t *buf, int page)
+{
+	struct fsl_ifc_mtd *priv = chip->priv;
+	struct fsl_ifc_ctrl *ctrl = priv->ctrl;
+
+	fsl_ifc_read_buf(mtd, buf, mtd->writesize);
+	fsl_ifc_read_buf(mtd, chip->oob_poi, mtd->oobsize);
+
+	if (ctrl->status != IFC_NAND_EVTER_STAT_OPC)
+		mtd->ecc_stats.failed++;
+
+	return 0;
+}
+
+/* ECC will be calculated automatically, and errors will be detected in
+ * waitfunc.
+ */
+static void fsl_ifc_write_page(struct mtd_info *mtd,
+				struct nand_chip *chip,
+				const uint8_t *buf)
+{
+	fsl_ifc_write_buf(mtd, buf, mtd->writesize);
+	fsl_ifc_write_buf(mtd, chip->oob_poi, mtd->oobsize);
+}
+
+static void fsl_ifc_ctrl_init(void)
+{
+	ifc_ctrl = kzalloc(sizeof(*ifc_ctrl), GFP_KERNEL);
+	if (!ifc_ctrl)
+		return;
+
+	ifc_ctrl->regs = IFC_BASE_ADDR;
+
+	/* clear event registers */
+	out_be32(&ifc_ctrl->regs->ifc_nand.nand_evter_stat, ~0U);
+	out_be32(&ifc_ctrl->regs->ifc_nand.pgrdcmpl_evt_stat, ~0U);
+
+	/* Enable error and event for any detected errors */
+	out_be32(&ifc_ctrl->regs->ifc_nand.nand_evter_en,
+			IFC_NAND_EVTER_EN_OPC_EN |
+			IFC_NAND_EVTER_EN_PGRDCMPL_EN |
+			IFC_NAND_EVTER_EN_FTOER_EN |
+			IFC_NAND_EVTER_EN_WPER_EN);
+
+	out_be32(&ifc_ctrl->regs->ifc_nand.ncfgr, 0x0);
+}
+
+static void fsl_ifc_select_chip(struct mtd_info *mtd, int chip)
+{
+}
+
+int board_nand_init(struct nand_chip *nand)
+{
+	struct fsl_ifc_mtd *priv;
+	struct nand_ecclayout *layout;
+	uint32_t cspr = 0, csor = 0;
+
+	if (!ifc_ctrl) {
+		fsl_ifc_ctrl_init();
+		if (!ifc_ctrl)
+			return -1;
+	}
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->ctrl = ifc_ctrl;
+	priv->vbase = nand->IO_ADDR_R;
+
+	/* Find which chip select it is connected to.
+	 */
+	for (priv->bank = 0; priv->bank < MAX_BANKS; priv->bank++) {
+		phys_addr_t base_addr = virt_to_phys(nand->IO_ADDR_R);
+
+		cspr = in_be32(&ifc_ctrl->regs->cspr_cs[priv->bank].cspr);
+		csor = in_be32(&ifc_ctrl->regs->csor_cs[priv->bank].csor);
+
+		if ((cspr & CSPR_V) && (cspr & CSPR_MSEL) == CSPR_MSEL_NAND &&
+		    (cspr & CSPR_BA) == CSPR_PHYS_ADDR(base_addr)) {
+			ifc_ctrl->cs_nand = priv->bank << IFC_NAND_CSEL_SHIFT;
+			break;
+		}
+	}
+
+	if (priv->bank >= MAX_BANKS) {
+		printf("%s: address did not match any "
+		       "chip selects\n", __func__);
+		return -ENODEV;
+	}
+
+	ifc_ctrl->chips[priv->bank] = priv;
+
+	/* fill in nand_chip structure */
+	/* set up function call table */
+
+	nand->write_buf = fsl_ifc_write_buf;
+	nand->read_buf = fsl_ifc_read_buf;
+	nand->verify_buf = fsl_ifc_verify_buf;
+	nand->select_chip = fsl_ifc_select_chip;
+	nand->cmdfunc = fsl_ifc_cmdfunc;
+	nand->waitfunc = fsl_ifc_wait;
+
+	/* set up nand options */
+	nand->bbt_td = &bbt_main_descr;
+	nand->bbt_md = &bbt_mirror_descr;
+
+	/* set up nand options */
+	nand->options = NAND_NO_READRDY | NAND_NO_AUTOINCR |
+			NAND_USE_FLASH_BBT;
+
+	if (cspr & CSPR_PORT_SIZE_16) {
+		nand->read_byte = fsl_ifc_read_byte16;
+		nand->options |= NAND_BUSWIDTH_16;
+	} else {
+		nand->read_byte = fsl_ifc_read_byte;
+	}
+
+	nand->controller = &ifc_ctrl->controller;
+	nand->priv = priv;
+
+	nand->ecc.read_page = fsl_ifc_read_page;
+	nand->ecc.write_page = fsl_ifc_write_page;
+
+	/* Hardware generates ECC per 512 Bytes */
+	nand->ecc.size = 512;
+	nand->ecc.bytes = 8;
+
+	switch (csor & CSOR_NAND_PGS_MASK) {
+	case CSOR_NAND_PGS_512:
+		if (nand->options & NAND_BUSWIDTH_16) {
+			layout = &oob_512_16bit_ecc4;
+		} else {
+			layout = &oob_512_8bit_ecc4;
+
+			/* Avoid conflict with bad block marker */
+			bbt_main_descr.offs = 0;
+			bbt_mirror_descr.offs = 0;
+		}
+
+		priv->bufnum_mask = 15;
+		break;
+
+	case CSOR_NAND_PGS_2K:
+		layout = &oob_2048_ecc4;
+		priv->bufnum_mask = 3;
+		break;
+
+	case CSOR_NAND_PGS_4K:
+		if ((csor & CSOR_NAND_ECC_MODE_MASK) ==
+		    CSOR_NAND_ECC_MODE_4) {
+			layout = &oob_4096_ecc4;
+		} else {
+			layout = &oob_4096_ecc8;
+			nand->ecc.bytes = 16;
+		}
+
+		priv->bufnum_mask = 1;
+		break;
+
+	default:
+		printf("ifc nand: bad csor %#x: bad page size\n", csor);
+		return -ENODEV;
+	}
+
+	/* Must also set CSOR_NAND_ECC_ENC_EN if DEC_EN set */
+	if (csor & CSOR_NAND_ECC_DEC_EN) {
+		nand->ecc.mode = NAND_ECC_HW;
+		nand->ecc.layout = layout;
+	} else {
+		nand->ecc.mode = NAND_ECC_SOFT;
+	}
+
+	return 0;
+}