diff mbox

[U-Boot,22/34] nand: Add zynq nand controller driver support

Message ID 7f401951-9160-4882-ab57-12beea3c621d@AM1EHSMHS001.ehs.local
State Accepted
Delegated to: Michal Simek
Headers show

Commit Message

Jagannadha Sutradharudu Teki Nov. 5, 2013, 5:46 p.m. UTC
Added support for Zynq Nand controller driver.

Signed-off-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
---
 arch/arm/include/asm/arch-zynq/hardware.h |    2 +
 drivers/mtd/nand/Makefile                 |    1 +
 drivers/mtd/nand/zynq_nand.c              | 1200 +++++++++++++++++++++++++++++
 3 files changed, 1203 insertions(+)
 create mode 100644 drivers/mtd/nand/zynq_nand.c

Comments

Scott Wood Nov. 13, 2013, 3:09 a.m. UTC | #1
On Tue, 2013-11-05 at 23:16 +0530, Jagannadha Sutradharudu Teki wrote:
> +#define zynq_nand_smc_base	((struct zynq_nand_smc_regs *)ZYNQ_SMC_BASEADDR)

__iomem

Please consider running sparse on new code.

> +/*
> + * struct zynq_nand_command_format - Defines NAND flash command format
> + * @start_cmd:		First cycle command (Start command)
> + * @end_cmd:		Second cycle command (Last command)
> + * @addr_cycles:	Number of address cycles required to send the address
> + * @end_cmd_valid:	The second cycle command is valid for cmd or data phase
> + */
> +struct zynq_nand_command_format {
> +	int start_cmd;
> +	int end_cmd;
> +	u8 addr_cycles;
> +	u8 end_cmd_valid;
> +};

Why are the first two "int" and the second two "u8"?

> +
> +/*
> + * struct zynq_nand_info - Defines the NAND flash driver instance
> + * @parts:		Pointer to the mtd_partition structure
> + * @nand_base:		Virtual address of the NAND flash device
> + * @end_cmd_pending:	End command is pending
> + * @end_cmd:		End command
> + */
> +struct zynq_nand_info {
> +#ifdef CONFIG_MTD_PARTITIONS
> +	struct mtd_partition	*parts;
> +#endif
> +	void __iomem		*nand_base;
> +	unsigned long		end_cmd_pending;
> +	unsigned long		end_cmd;
> +};

Why long?

> +
> +#define ONDIE_ECC_FEATURE_ADDR	0x90
> +
> +/*  The NAND flash operations command format */
> +static const struct zynq_nand_command_format zynq_nand_commands[] = {
> +	{NAND_CMD_READ0, NAND_CMD_READSTART, 5, ZYNQ_NAND_CMD_PHASE},
> +	{NAND_CMD_RNDOUT, NAND_CMD_RNDOUTSTART, 2, ZYNQ_NAND_CMD_PHASE},
> +	{NAND_CMD_READID, NAND_CMD_NONE, 1, NAND_CMD_NONE},
> +	{NAND_CMD_STATUS, NAND_CMD_NONE, 0, NAND_CMD_NONE},
> +	{NAND_CMD_SEQIN, NAND_CMD_PAGEPROG, 5, ZYNQ_NAND_DATA_PHASE},
> +	{NAND_CMD_RNDIN, NAND_CMD_NONE, 2, NAND_CMD_NONE},
> +	{NAND_CMD_ERASE1, NAND_CMD_ERASE2, 3, ZYNQ_NAND_CMD_PHASE},
> +	{NAND_CMD_RESET, NAND_CMD_NONE, 0, NAND_CMD_NONE},
> +	{NAND_CMD_PARAM, NAND_CMD_NONE, 1, NAND_CMD_NONE},
> +	{NAND_CMD_GET_FEATURES, NAND_CMD_NONE, 1, NAND_CMD_NONE},
> +	{NAND_CMD_SET_FEATURES, NAND_CMD_NONE, 1, NAND_CMD_NONE},
> +	{NAND_CMD_NONE, NAND_CMD_NONE, 0, 0},

I'm not sure that NAND_CMD_NONE is appropriate for end_cmd_valid -- it's
not a field that otherwise takes NAND_CMD_xxx values.  Just use zero.

> +	/* Add all the flash commands supported by the flash device and Linux
> +	 * The cache program command is not supported by driver because driver
> +	 * cant differentiate between page program and cached page program from
> +	 * start command, these commands can be differentiated through end
> +	 * command, which doesn't fit in to the driver design. The cache program
> +	 * command is not supported by NAND subsystem also, look at 1612 line
> +	 * number (in nand_write_page function) of nand_base.c file.
> +	 * {NAND_CMD_SEQIN, NAND_CMD_CACHEDPROG, 5, ZYNQ_NAND_YES}
> +	 */

What is ZYNQ_NAND_YES?

> +};
> +
> +/* Define default oob placement schemes for large and small page devices */
> +static struct nand_ecclayout nand_oob_16 = {
> +	.eccbytes = 3,
> +	.eccpos = {13, 14, 15},
> +	.oobfree = {
> +		{ .offset = 0, .length = 12 }
> +	}
> +};

Isn't your oobfree overlapping the bad block marker?

Normally (with small-page NAND) the marker is at offset 5 for 8-bit and
offset 0 for 16-bit, not at offset 12.

> +	/* Wait max 10ms */
> +	timeout = 10;
> +	status = readl(&zynq_nand_smc_base->esr);
> +	while (status & ZYNQ_NAND_ECC_BUSY) {
> +		status = readl(&zynq_nand_smc_base->esr);
> +		if (timeout == 0)
> +			return -1;
> +		timeout--;
> +		udelay(1);
> +	}

Comment says 10ms, code says 10us.

> +
> +	return status;
> +}
> +
> +/*
> + * zynq_nand_init_nand_flash - Initialize NAND controller
> + * @option:	Device property flags
> + *
> + * This function initializes the NAND flash interface on the NAND controller.
> + *
> + * returns:	0 on success or error value on failure
> + */
> +static int zynq_nand_init_nand_flash(int option)
> +{
> +	u32 status;
> +
> +	/* disable interrupts */
> +	writel(ZYNQ_NAND_CLR_CONFIG, &zynq_nand_smc_base->cfr);
> +	/* Initialize the NAND interface by setting cycles and operation mode */
> +	writel(ZYNQ_NAND_SET_CYCLES, &zynq_nand_smc_base->scr);
> +	if (option & NAND_BUSWIDTH_16)
> +		writel((ZYNQ_NAND_SET_OPMODE | 0x1), &zynq_nand_smc_base->sor);
> +	else
> +		writel(ZYNQ_NAND_SET_OPMODE, &zynq_nand_smc_base->sor);

That 0x1 should be defined symbolically.

> +		/* ECC value valid */
> +		if (ecc_status & 0x40) {

0x40 should be defined symbolically.

> +/*
> + * onehot - onehot function
> + * @value:	value to check for onehot
> + *
> + * This function checks whether a value is onehot or not.
> + * onehot is if and only if onebit is set.
> + *
> + */
> +static int onehot(unsigned short value)
> +{
> +	return ((value & (value-1)) == 0);
> +}

Too many parentheses, and need spaces around '-'.
Why "unsigned short"?
Why use an obscure (at least to software people) name for this, rather
than some variant of "power of 2", or even "one_bit_set"?
s/onebit/one bit/

Note that the above function will also return true if no bits are set,
which contradicts the definition in the comment (yes, I know you don't
call it under such circumstances).

Function should return bool.

> +/*
> + * zynq_nand_correct_data - ECC correction function
> + * @mtd:	Pointer to the mtd_info structure
> + * @buf:	Pointer to the page data
> + * @read_ecc:	Pointer to the ECC value read from spare data area
> + * @calc_ecc:	Pointer to the calculated ECC value
> + *
> + * This function corrects the ECC single bit errors & detects 2-bit errors.
> + *
> + * returns:	0 if no ECC errors found
> + *		1 if single bit error found and corrected.
> + *		-1 if multiple ECC errors found.
> + */
> +static int zynq_nand_correct_data(struct mtd_info *mtd, unsigned char *buf,
> +			unsigned char *read_ecc, unsigned char *calc_ecc)
> +{
> +	unsigned char bit_addr;
> +	unsigned int byte_addr;
> +	unsigned short ecc_odd, ecc_even;
> +	unsigned short read_ecc_lower, read_ecc_upper;
> +	unsigned short calc_ecc_lower, calc_ecc_upper;
> +
> +	read_ecc_lower = (read_ecc[0] | (read_ecc[1] << 8)) & 0xfff;
> +	read_ecc_upper = ((read_ecc[1] >> 4) | (read_ecc[2] << 4)) & 0xfff;
> +
> +	calc_ecc_lower = (calc_ecc[0] | (calc_ecc[1] << 8)) & 0xfff;
> +	calc_ecc_upper = ((calc_ecc[1] >> 4) | (calc_ecc[2] << 4)) & 0xfff;
> +
> +	ecc_odd = read_ecc_lower ^ calc_ecc_lower;
> +	ecc_even = read_ecc_upper ^ calc_ecc_upper;
> +
> +	if ((ecc_odd == 0) && (ecc_even == 0))
> +		return 0;       /* no error */
> +	else if (ecc_odd == (~ecc_even & 0xfff)) {
> +		/* bits [11:3] of error code is byte offset */
> +		byte_addr = (ecc_odd >> 3) & 0x1ff;
> +		/* bits [2:0] of error code is bit offset */
> +		bit_addr = ecc_odd & 0x7;
> +		/* Toggling error bit */
> +		buf[byte_addr] ^= (1 << bit_addr);
> +		return 1;
> +	} else if (onehot(ecc_odd | ecc_even) == 1) {
> +		return 1; /* one error in parity */
> +	} else {
> +		return -1; /* Uncorrectable error */
> +	}
> +}

You don't need "else" after "return"...

> +
> +/*
> + * zynq_nand_read_oob - [REPLACABLE] the most common OOB data read function

The version in nand_base.c is replaceable and (perhaps) the most common
implementation, but this one isn't.

> + * @mtd:	mtd info structure
> + * @chip:	nand chip info structure
> + * @page:	page number to read
> + * @sndcmd:	flag whether to issue read command or not
> + */
> +static int zynq_nand_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
> +			int page)
> +{
> +	unsigned long data_width = 4;

Why long?

> +	unsigned long data_phase_addr = 0;
> +	u8 *p;
> +
> +	chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
> +
> +	p = chip->oob_poi;
> +	chip->read_buf(mtd, p, (mtd->oobsize - data_width));
> +	p += (mtd->oobsize - data_width);

Unnecessary parentheses.  Likewise elsewhere in the patch.

> +static int zynq_nand_write_page_hwecc(struct mtd_info *mtd,
> +	struct nand_chip *chip, const u8 *buf, int oob_required)
> +{
> +	int i, eccsize = chip->ecc.size;
> +	int eccsteps = chip->ecc.steps;
> +	u8 *ecc_calc = chip->buffers->ecccalc;
> +	const u8 *p = buf;
> +	u32 *eccpos = chip->ecc.layout->eccpos;
> +	unsigned long data_phase_addr = 0;
> +	unsigned long data_width = 4;
> +	u8 *oob_ptr;
> +
> +	for (; (eccsteps - 1); eccsteps--) {
> +		chip->write_buf(mtd, p, eccsize);
> +		p += eccsize;
> +	}

Why is eccsteps initialized at the declaration rather than as part of
the loop?

> +/*
> + * zynq_nand_write_page_swecc - [REPLACABLE] software ecc based page
> + * write function

Is there a reason you need both hwecc and swecc support?

More importantly, is there a reason why you need to duplicate these
functions for swecc?  I don't see any difference versus the original in
nand_base.c.

> +/*
> + * zynq_nand_select_chip - Select the flash device
> + * @mtd:	Pointer to the mtd_info structure
> + * @chip:	Chip number to be selected
> + *
> + * This function is empty as the NAND controller handles chip select line
> + * internally based on the chip address passed in command and data phase.
> + */
> +static void zynq_nand_select_chip(struct mtd_info *mtd, int chip)
> +{
> +	return;
> +}

"return;" is unnecessary

> +/*
> + * zynq_nand_cmd_function - Send command to NAND device
> + * @mtd:	Pointer to the mtd_info structure
> + * @command:	The command to be sent to the flash device
> + * @column:	The column address for this command, -1 if none
> + * @page_addr:	The page address for this command, -1 if none
> + */
> +static void zynq_nand_cmd_function(struct mtd_info *mtd, unsigned int command,
> +				 int column, int page_addr)
> +{
> +	struct nand_chip *chip = mtd->priv;
> +	const struct zynq_nand_command_format *curr_cmd = NULL;
> +	struct zynq_nand_info *xnand;
> +	void *cmd_addr;
> +	unsigned long cmd_data = 0;
> +	unsigned long cmd_phase_addr = 0;
> +	unsigned long data_phase_addr = 0;
> +	unsigned long end_cmd = 0;
> +	unsigned long end_cmd_valid = 0;
> +	unsigned long i;

Other than the addresses, why long?

> +
> +	xnand = (struct zynq_nand_info *)chip->priv;
> +	if (xnand->end_cmd_pending) {
> +		/* Check for end command if this command request is same as the
> +		 * pending command then return
> +		 */
> +		if (xnand->end_cmd == command) {
> +			xnand->end_cmd = 0;
> +			xnand->end_cmd_pending = 0;
> +			return;
> +		}
> +	}
> +
> +	/* Emulate NAND_CMD_READOOB for large page device */
> +	if ((mtd->writesize > ZYNQ_NAND_ECC_SIZE) &&
> +	    (command == NAND_CMD_READOOB)) {
> +		column += mtd->writesize;
> +		command = NAND_CMD_READ0;
> +	}
> +
> +	/* Get the command format */
> +	for (i = 0; (zynq_nand_commands[i].start_cmd != NAND_CMD_NONE ||
> +		zynq_nand_commands[i].end_cmd != NAND_CMD_NONE); i++) {
> +		if (command == zynq_nand_commands[i].start_cmd)

Please do not line up the continuation line with the loop body.

Why not use "i < ARRAY_SIZE(zynq_nand_commands)" instead, and get rid of
the sentinel?

> +			curr_cmd = &zynq_nand_commands[i];
> +	}
> +	if (curr_cmd == NULL)
> +		return;
> +
> +	/* Clear interrupt */
> +	writel((1 << 4), &zynq_nand_smc_base->cfr);

1 << 4 should be defined symbolically.

> +	} else
> +		;

Get rid of that else.

> +	writel(cmd_data, cmd_addr);
> +
> +	if (curr_cmd->end_cmd_valid) {
> +		xnand->end_cmd = curr_cmd->end_cmd;
> +		xnand->end_cmd_pending = 1;
> +	}
> +
> +	ndelay(100);
> +
> +	if ((command == NAND_CMD_READ0) ||
> +	    (command == NAND_CMD_RESET) ||
> +	    (command == NAND_CMD_PARAM) ||
> +	    (command == NAND_CMD_GET_FEATURES)) {
> +		while (!chip->dev_ready(mtd))
> +				;

Timeout?

> +		return;
> +	}
> +}

That "return;" does nothing.

> +/*
> + * zynq_nand_read_buf - read chip data into buffer
> + * @mtd:        MTD device structure
> + * @buf:        buffer to store date
> + * @len:        number of bytes to read
> + */
> +static void zynq_nand_read_buf(struct mtd_info *mtd, u8 *buf, int len)
> +{
> +	struct nand_chip *chip = mtd->priv;
> +	const u32 *nand = chip->IO_ADDR_R;
> +
> +	/* Make sure that buf is 32 bit aligned */
> +	if (((int)buf & 0x3) != 0) {
> +		if (((int)buf & 0x1) != 0) {
> +			if (len) {
> +				*buf = readb(nand);
> +				buf += 1;
> +				len--;
> +			}
> +		}

Don't cast pointers to "int".  Use (unsigned) long or (u)intptr_t.

> +		if (((int)buf & 0x3) != 0) {
> +			if (len >= 2) {
> +				*(u16 *)buf = readw(nand);

I believe this violates C99 aliasing rules.

> +				buf += 2;
> +				len -= 2;
> +			}
> +		}
> +	}
> +
> +	/* copy aligned data */
> +	while (len >= 4) {
> +		*(u32 *)buf = readl(nand);

Likewise.

For why GCC doesn't complain (or at least a characterization of when it
doesn't complain), see this:
http://cellperformance.beyond3d.com/articles/2006/06/understanding-strict-aliasing.html

That said, I'm not sure how one would do this without violating strict
aliasing (other than with inline asm), and as long as this function
never gets inlined, GCC should produce code that's OK.

> +static int zynq_nand_init(struct nand_chip *nand_chip, int devnum)
> +{
> +	struct zynq_nand_info *xnand;
> +	struct mtd_info *mtd;
> +	unsigned long ecc_page_size;
> +	int err = -1;
> +	u8 maf_id, dev_id, i;
> +	u8 get_feature[4];
> +	u8 set_feature[4] = {0x08, 0x00, 0x00, 0x00};
> +	unsigned long ecc_cfg;
> +	int ondie_ecc_enabled = 0;

Does that 0x08 have a symbolic name?

> 	if (ondie_ecc_enabled) {
> +		/* bypass the controller ECC block */
> +		ecc_cfg = readl(&zynq_nand_smc_base->emcr);
> +		ecc_cfg &= ~0xc;
> +		writel(ecc_cfg, &zynq_nand_smc_base->emcr);
> +
> +		/* The software ECC routines won't work
> +		 * with the SMC controller
> +		 */
> +		nand_chip->ecc.mode = NAND_ECC_HW;
> +		nand_chip->ecc.strength = 1;
> +		nand_chip->ecc.read_page = zynq_nand_read_page_raw_nooob;
> +		nand_chip->ecc.read_subpage = zynq_nand_read_subpage_raw;
> +		nand_chip->ecc.write_page = zynq_nand_write_page_raw;
> +		nand_chip->ecc.read_page_raw = zynq_nand_read_page_raw;
> +		nand_chip->ecc.write_page_raw = zynq_nand_write_page_raw;
> +		nand_chip->ecc.read_oob = zynq_nand_read_oob;
> +		nand_chip->ecc.write_oob = zynq_nand_write_oob;
> +		nand_chip->ecc.size = mtd->writesize;
> +		nand_chip->ecc.bytes = 0;
> +
> +		/* NAND with on-die ECC supports subpage reads */
> +		nand_chip->options |= NAND_SUBPAGE_READ;
> +
> +		/* On-Die ECC spare bytes offset 8 is used for ECC codes */
> +		if (ondie_ecc_enabled) {
> +			nand_chip->ecc.layout = &ondie_nand_oob_64;
> +			/* Use the BBT pattern descriptors */
> +			nand_chip->bbt_td = &bbt_main_descr;
> +			nand_chip->bbt_md = &bbt_mirror_descr;
> +		}
> +	} else {
> +		/* Hardware ECC generates 3 bytes ECC code for each 512 bytes */
> +		nand_chip->ecc.mode = NAND_ECC_HW;
> +		nand_chip->ecc.strength = 1;
> +		nand_chip->ecc.size = ZYNQ_NAND_ECC_SIZE;
> +		nand_chip->ecc.bytes = 3;
> +		nand_chip->ecc.calculate = zynq_nand_calculate_hwecc;
> +		nand_chip->ecc.correct = zynq_nand_correct_data;
> +		nand_chip->ecc.hwctl = NULL;
> +		nand_chip->ecc.read_page = zynq_nand_read_page_hwecc;
> +		nand_chip->ecc.write_page = zynq_nand_write_page_hwecc;
> +		nand_chip->ecc.read_page_raw = zynq_nand_read_page_raw;
> +		nand_chip->ecc.write_page_raw = zynq_nand_write_page_raw;
> +		nand_chip->ecc.read_oob = zynq_nand_read_oob;
> +		nand_chip->ecc.write_oob = zynq_nand_write_oob;
> +
> +		switch (mtd->writesize) {
> +		case 512:
> +			ecc_page_size = 0x1;
> +			/* Set the ECC memory config register */
> +			writel((ZYNQ_NAND_ECC_CONFIG | ecc_page_size),
> +			       &zynq_nand_smc_base->emcr);
> +			break;
> +		case 1024:
> +			ecc_page_size = 0x2;
> +			/* Set the ECC memory config register */
> +			writel((ZYNQ_NAND_ECC_CONFIG | ecc_page_size),
> +			       &zynq_nand_smc_base->emcr);
> +			break;
> +		case 2048:
> +			ecc_page_size = 0x3;
> +			/* Set the ECC memory config register */
> +			writel((ZYNQ_NAND_ECC_CONFIG | ecc_page_size),
> +			       &zynq_nand_smc_base->emcr);
> +			break;
> +		default:
> +			/* The software ECC routines won't work with
> +			 * the SMC controller
> +			 */
> +			nand_chip->ecc.mode = NAND_ECC_HW;
> +			nand_chip->ecc.calculate = nand_calculate_ecc;
> +			nand_chip->ecc.correct = nand_correct_data;
> +			nand_chip->ecc.read_page = zynq_nand_read_page_swecc;
> +			/* nand_chip->ecc.read_subpage = nand_read_subpage; */
> +			nand_chip->ecc.write_page = zynq_nand_write_page_swecc;

Why do you have NAND_ECC_HW together with zynq_nand_*_page_swecc?

> +			nand_chip->ecc.read_page_raw = zynq_nand_read_page_raw;
> +			nand_chip->ecc.write_page_raw =
> +						zynq_nand_write_page_raw;
> +			nand_chip->ecc.read_oob = zynq_nand_read_oob;
> +			nand_chip->ecc.write_oob = zynq_nand_write_oob;
> +			nand_chip->ecc.size = 256;
> +			nand_chip->ecc.bytes = 3;
> +			break;
> +		}
> +
> +		if (mtd->oobsize == 16)
> +			nand_chip->ecc.layout = &nand_oob_16;
> +		else if (mtd->oobsize == 64)
> +			nand_chip->ecc.layout = &nand_oob_64;
> +		else
> +			;
> +	}

There seems to be some duplicated things above that do the same thing on
every possible code path (or even multiple times on the same codepath,
such as setting nand_chip->ecc.mode to NAND_ECC_HW).

And again, get rid of that do-nothing "else".

-Scott
diff mbox

Patch

diff --git a/arch/arm/include/asm/arch-zynq/hardware.h b/arch/arm/include/asm/arch-zynq/hardware.h
index 05870ae..f2c76a6 100644
--- a/arch/arm/include/asm/arch-zynq/hardware.h
+++ b/arch/arm/include/asm/arch-zynq/hardware.h
@@ -20,6 +20,8 @@ 
 #define ZYNQ_SPI_BASEADDR0		0xE0006000
 #define ZYNQ_SPI_BASEADDR1		0xE0007000
 #define ZYNQ_QSPI_BASEADDR		0xE000D000
+#define ZYNQ_SMC_BASEADDR		0xE000E000
+#define ZYNQ_NAND_BASEADDR		0xE1000000
 #define ZYNQ_DDRC_BASEADDR		0xF8006000
 
 /* Reflect slcr offsets */
diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
index eb1eafa..fcd6160 100644
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -60,6 +60,7 @@  obj-$(CONFIG_TEGRA_NAND) += tegra_nand.o
 obj-$(CONFIG_NAND_OMAP_GPMC) += omap_gpmc.o
 obj-$(CONFIG_NAND_PLAT) += nand_plat.o
 obj-$(CONFIG_NAND_DOCG4) += docg4.o
+obj-$(CONFIG_NAND_ZYNQ) += zynq_nand.o
 
 else  # minimal SPL drivers
 
diff --git a/drivers/mtd/nand/zynq_nand.c b/drivers/mtd/nand/zynq_nand.c
new file mode 100644
index 0000000..3e168fc
--- /dev/null
+++ b/drivers/mtd/nand/zynq_nand.c
@@ -0,0 +1,1200 @@ 
+/*
+ * (C) Copyright 2013 Xilinx, Inc.
+ *
+ * Xilinx Zynq NAND Flash Controller Driver
+ * This driver is based on plat_nand.c and mxc_nand.c drivers
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <asm/io.h>
+#include <asm/errno.h>
+#include <nand.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mtd/nand_ecc.h>
+#include <asm/arch/hardware.h>
+
+/* The NAND flash driver defines */
+#define ZYNQ_NAND_CMD_PHASE	1	/* End command valid in command phase */
+#define ZYNQ_NAND_DATA_PHASE	2	/* End command valid in data phase */
+#define ZYNQ_NAND_ECC_SIZE	512	/* Size of data for ECC operation */
+
+/* Flash memory controller operating parameters */
+#define ZYNQ_NAND_CLR_CONFIG	((0x1 << 1)  |	/* Disable interrupt */ \
+				(0x1 << 4)   |	/* Clear interrupt */ \
+				(0x1 << 6))	/* Disable ECC interrupt */
+
+/* Assuming 50MHz clock (20ns cycle time) and 3V operation */
+#define ZYNQ_NAND_SET_CYCLES	((0x2 << 20) |	/* t_rr from nand_cycles */ \
+				(0x2 << 17)  |	/* t_ar from nand_cycles */ \
+				(0x1 << 14)  |	/* t_clr from nand_cycles */ \
+				(0x3 << 11)  |	/* t_wp from nand_cycles */ \
+				(0x2 << 8)   |	/* t_rea from nand_cycles */ \
+				(0x5 << 4)   |	/* t_wc from nand_cycles */ \
+				(0x5 << 0))	/* t_rc from nand_cycles */
+
+#define ZYNQ_NAND_SET_OPMODE	0x0
+
+#define ZYNQ_NAND_DIRECT_CMD	((0x4 << 23) |	/* Chip 0 from interface 1 */ \
+				(0x2 << 21))	/* UpdateRegs operation */
+
+#define ZYNQ_NAND_ECC_CONFIG	((0x1 << 2)  |	/* ECC available on APB */ \
+				(0x1 << 4)   |	/* ECC read at end of page */ \
+				(0x0 << 5))	/* No Jumping */
+
+#define ZYNQ_NAND_ECC_CMD1	((0x80)      |	/* Write command */ \
+				(0x00 << 8)  |	/* Read command */ \
+				(0x30 << 16) |	/* Read End command */ \
+				(0x1 << 24))	/* Read End command calid */
+
+#define ZYNQ_NAND_ECC_CMD2	((0x85)      |	/* Write col change cmd */ \
+				(0x05 << 8)  |	/* Read col change cmd */ \
+				(0xE0 << 16) |	/* Read col change end cmd */ \
+				(0x1 << 24))	/* Read col change
+							end cmd valid */
+/* AXI Address definitions */
+#define START_CMD_SHIFT		3
+#define END_CMD_SHIFT		11
+#define END_CMD_VALID_SHIFT	20
+#define ADDR_CYCLES_SHIFT	21
+#define CLEAR_CS_SHIFT		21
+#define ECC_LAST_SHIFT		10
+#define COMMAND_PHASE		(0 << 19)
+#define DATA_PHASE		(1 << 19)
+
+#define ZYNQ_NAND_ECC_LAST	(1 << ECC_LAST_SHIFT)	/* Set ECC_Last */
+#define ZYNQ_NAND_CLEAR_CS	(1 << CLEAR_CS_SHIFT)	/* Clear chip select */
+
+/* ECC block registers bit position and bit mask */
+#define ZYNQ_NAND_ECC_BUSY	(1 << 6)	/* ECC block is busy */
+#define ZYNQ_NAND_ECC_MASK	0x00FFFFFF	/* ECC value mask */
+
+/* SMC register set */
+struct zynq_nand_smc_regs {
+	u32 csr;		/* 0x00 */
+	u32 reserved0[2];
+	u32 cfr;		/* 0x0C */
+	u32 dcr;		/* 0x10 */
+	u32 scr;		/* 0x14 */
+	u32 sor;		/* 0x18 */
+	u32 reserved1[249];
+	u32 esr;		/* 0x400 */
+	u32 emcr;		/* 0x404 */
+	u32 emcmd1r;		/* 0x408 */
+	u32 emcmd2r;		/* 0x40C */
+	u32 reserved2[2];
+	u32 eval0r;		/* 0x418 */
+};
+#define zynq_nand_smc_base	((struct zynq_nand_smc_regs *)ZYNQ_SMC_BASEADDR)
+
+/*
+ * struct zynq_nand_command_format - Defines NAND flash command format
+ * @start_cmd:		First cycle command (Start command)
+ * @end_cmd:		Second cycle command (Last command)
+ * @addr_cycles:	Number of address cycles required to send the address
+ * @end_cmd_valid:	The second cycle command is valid for cmd or data phase
+ */
+struct zynq_nand_command_format {
+	int start_cmd;
+	int end_cmd;
+	u8 addr_cycles;
+	u8 end_cmd_valid;
+};
+
+/*
+ * struct zynq_nand_info - Defines the NAND flash driver instance
+ * @parts:		Pointer to the mtd_partition structure
+ * @nand_base:		Virtual address of the NAND flash device
+ * @end_cmd_pending:	End command is pending
+ * @end_cmd:		End command
+ */
+struct zynq_nand_info {
+#ifdef CONFIG_MTD_PARTITIONS
+	struct mtd_partition	*parts;
+#endif
+	void __iomem		*nand_base;
+	unsigned long		end_cmd_pending;
+	unsigned long		end_cmd;
+};
+
+#define ONDIE_ECC_FEATURE_ADDR	0x90
+
+/*  The NAND flash operations command format */
+static const struct zynq_nand_command_format zynq_nand_commands[] = {
+	{NAND_CMD_READ0, NAND_CMD_READSTART, 5, ZYNQ_NAND_CMD_PHASE},
+	{NAND_CMD_RNDOUT, NAND_CMD_RNDOUTSTART, 2, ZYNQ_NAND_CMD_PHASE},
+	{NAND_CMD_READID, NAND_CMD_NONE, 1, NAND_CMD_NONE},
+	{NAND_CMD_STATUS, NAND_CMD_NONE, 0, NAND_CMD_NONE},
+	{NAND_CMD_SEQIN, NAND_CMD_PAGEPROG, 5, ZYNQ_NAND_DATA_PHASE},
+	{NAND_CMD_RNDIN, NAND_CMD_NONE, 2, NAND_CMD_NONE},
+	{NAND_CMD_ERASE1, NAND_CMD_ERASE2, 3, ZYNQ_NAND_CMD_PHASE},
+	{NAND_CMD_RESET, NAND_CMD_NONE, 0, NAND_CMD_NONE},
+	{NAND_CMD_PARAM, NAND_CMD_NONE, 1, NAND_CMD_NONE},
+	{NAND_CMD_GET_FEATURES, NAND_CMD_NONE, 1, NAND_CMD_NONE},
+	{NAND_CMD_SET_FEATURES, NAND_CMD_NONE, 1, NAND_CMD_NONE},
+	{NAND_CMD_NONE, NAND_CMD_NONE, 0, 0},
+	/* Add all the flash commands supported by the flash device and Linux
+	 * The cache program command is not supported by driver because driver
+	 * cant differentiate between page program and cached page program from
+	 * start command, these commands can be differentiated through end
+	 * command, which doesn't fit in to the driver design. The cache program
+	 * command is not supported by NAND subsystem also, look at 1612 line
+	 * number (in nand_write_page function) of nand_base.c file.
+	 * {NAND_CMD_SEQIN, NAND_CMD_CACHEDPROG, 5, ZYNQ_NAND_YES}
+	 */
+};
+
+/* Define default oob placement schemes for large and small page devices */
+static struct nand_ecclayout nand_oob_16 = {
+	.eccbytes = 3,
+	.eccpos = {13, 14, 15},
+	.oobfree = {
+		{ .offset = 0, .length = 12 }
+	}
+};
+
+static struct nand_ecclayout nand_oob_64 = {
+	.eccbytes = 12,
+	.eccpos = {
+		   52, 53, 54, 55, 56, 57,
+		   58, 59, 60, 61, 62, 63},
+	.oobfree = {
+		{ .offset = 2, .length = 50 }
+	}
+};
+
+static struct nand_ecclayout ondie_nand_oob_64 = {
+	.eccbytes = 32,
+
+	.eccpos = {
+		8, 9, 10, 11, 12, 13, 14, 15,
+		24, 25, 26, 27, 28, 29, 30, 31,
+		40, 41, 42, 43, 44, 45, 46, 47,
+		56, 57, 58, 59, 60, 61, 62, 63
+	},
+
+	.oobfree = {
+		{ .offset = 4, .length = 4 },
+		{ .offset = 20, .length = 4 },
+		{ .offset = 36, .length = 4 },
+		{ .offset = 52, .length = 4 }
+	}
+};
+
+/* Generic flash bbt decriptors */
+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 | NAND_BBT_PERCHIP,
+	.offs = 4,
+	.len = 4,
+	.veroffs = 20,
+	.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 | NAND_BBT_PERCHIP,
+	.offs = 4,
+	.len = 4,
+	.veroffs = 20,
+	.maxblocks = 4,
+	.pattern = mirror_pattern
+};
+
+/*
+ * zynq_nand_waitfor_ecc_completion - Wait for ECC completion
+ *
+ * returns: status for command completion, -1 for Timeout
+ */
+static int zynq_nand_waitfor_ecc_completion(void)
+{
+	unsigned long timeout;
+	u32 status;
+
+	/* Wait max 10ms */
+	timeout = 10;
+	status = readl(&zynq_nand_smc_base->esr);
+	while (status & ZYNQ_NAND_ECC_BUSY) {
+		status = readl(&zynq_nand_smc_base->esr);
+		if (timeout == 0)
+			return -1;
+		timeout--;
+		udelay(1);
+	}
+
+	return status;
+}
+
+/*
+ * zynq_nand_init_nand_flash - Initialize NAND controller
+ * @option:	Device property flags
+ *
+ * This function initializes the NAND flash interface on the NAND controller.
+ *
+ * returns:	0 on success or error value on failure
+ */
+static int zynq_nand_init_nand_flash(int option)
+{
+	u32 status;
+
+	/* disable interrupts */
+	writel(ZYNQ_NAND_CLR_CONFIG, &zynq_nand_smc_base->cfr);
+	/* Initialize the NAND interface by setting cycles and operation mode */
+	writel(ZYNQ_NAND_SET_CYCLES, &zynq_nand_smc_base->scr);
+	if (option & NAND_BUSWIDTH_16)
+		writel((ZYNQ_NAND_SET_OPMODE | 0x1), &zynq_nand_smc_base->sor);
+	else
+		writel(ZYNQ_NAND_SET_OPMODE, &zynq_nand_smc_base->sor);
+
+	writel(ZYNQ_NAND_DIRECT_CMD, &zynq_nand_smc_base->dcr);
+
+	/* Wait till the ECC operation is complete */
+	status = zynq_nand_waitfor_ecc_completion();
+	if (status < 0) {
+		printf("%s: Timeout\n", __func__);
+		return status;
+	}
+
+	/* Set the command1 and command2 register */
+	writel(ZYNQ_NAND_ECC_CMD1, &zynq_nand_smc_base->emcmd1r);
+	writel(ZYNQ_NAND_ECC_CMD2, &zynq_nand_smc_base->emcmd2r);
+
+	return 0;
+}
+
+/*
+ * zynq_nand_calculate_hwecc - Calculate Hardware ECC
+ * @mtd:	Pointer to the mtd_info structure
+ * @data:	Pointer to the page data
+ * @ecc_code:	Pointer to the ECC buffer where ECC data needs to be stored
+ *
+ * This function retrieves the Hardware ECC data from the controller and returns
+ * ECC data back to the MTD subsystem.
+ *
+ * returns:	0 on success or error value on failure
+ */
+static int zynq_nand_calculate_hwecc(struct mtd_info *mtd, const u8 *data,
+		u8 *ecc_code)
+{
+	u32 ecc_value = 0;
+	u8 ecc_reg, ecc_byte;
+	u32 ecc_status;
+
+	/* Wait till the ECC operation is complete */
+	ecc_status = zynq_nand_waitfor_ecc_completion();
+	if (ecc_status < 0) {
+		printf("%s: Timeout\n", __func__);
+		return ecc_status;
+	}
+
+	for (ecc_reg = 0; ecc_reg < 4; ecc_reg++) {
+		/* Read ECC value for each block */
+		ecc_value = readl(&zynq_nand_smc_base->eval0r + ecc_reg);
+		ecc_status = (ecc_value >> 24) & 0xFF;
+		/* ECC value valid */
+		if (ecc_status & 0x40) {
+			for (ecc_byte = 0; ecc_byte < 3; ecc_byte++) {
+				/* Copy ECC bytes to MTD buffer */
+				*ecc_code = ecc_value & 0xFF;
+				ecc_value = ecc_value >> 8;
+				ecc_code++;
+			}
+		} else {
+			debug("%s: ecc status failed\n", __func__);
+		}
+	}
+	return 0;
+}
+
+/*
+ * onehot - onehot function
+ * @value:	value to check for onehot
+ *
+ * This function checks whether a value is onehot or not.
+ * onehot is if and only if onebit is set.
+ *
+ */
+static int onehot(unsigned short value)
+{
+	return ((value & (value-1)) == 0);
+}
+
+/*
+ * zynq_nand_correct_data - ECC correction function
+ * @mtd:	Pointer to the mtd_info structure
+ * @buf:	Pointer to the page data
+ * @read_ecc:	Pointer to the ECC value read from spare data area
+ * @calc_ecc:	Pointer to the calculated ECC value
+ *
+ * This function corrects the ECC single bit errors & detects 2-bit errors.
+ *
+ * returns:	0 if no ECC errors found
+ *		1 if single bit error found and corrected.
+ *		-1 if multiple ECC errors found.
+ */
+static int zynq_nand_correct_data(struct mtd_info *mtd, unsigned char *buf,
+			unsigned char *read_ecc, unsigned char *calc_ecc)
+{
+	unsigned char bit_addr;
+	unsigned int byte_addr;
+	unsigned short ecc_odd, ecc_even;
+	unsigned short read_ecc_lower, read_ecc_upper;
+	unsigned short calc_ecc_lower, calc_ecc_upper;
+
+	read_ecc_lower = (read_ecc[0] | (read_ecc[1] << 8)) & 0xfff;
+	read_ecc_upper = ((read_ecc[1] >> 4) | (read_ecc[2] << 4)) & 0xfff;
+
+	calc_ecc_lower = (calc_ecc[0] | (calc_ecc[1] << 8)) & 0xfff;
+	calc_ecc_upper = ((calc_ecc[1] >> 4) | (calc_ecc[2] << 4)) & 0xfff;
+
+	ecc_odd = read_ecc_lower ^ calc_ecc_lower;
+	ecc_even = read_ecc_upper ^ calc_ecc_upper;
+
+	if ((ecc_odd == 0) && (ecc_even == 0))
+		return 0;       /* no error */
+	else if (ecc_odd == (~ecc_even & 0xfff)) {
+		/* bits [11:3] of error code is byte offset */
+		byte_addr = (ecc_odd >> 3) & 0x1ff;
+		/* bits [2:0] of error code is bit offset */
+		bit_addr = ecc_odd & 0x7;
+		/* Toggling error bit */
+		buf[byte_addr] ^= (1 << bit_addr);
+		return 1;
+	} else if (onehot(ecc_odd | ecc_even) == 1) {
+		return 1; /* one error in parity */
+	} else {
+		return -1; /* Uncorrectable error */
+	}
+}
+
+/*
+ * zynq_nand_read_oob - [REPLACABLE] the most common OOB data read function
+ * @mtd:	mtd info structure
+ * @chip:	nand chip info structure
+ * @page:	page number to read
+ * @sndcmd:	flag whether to issue read command or not
+ */
+static int zynq_nand_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
+			int page)
+{
+	unsigned long data_width = 4;
+	unsigned long data_phase_addr = 0;
+	u8 *p;
+
+	chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
+
+	p = chip->oob_poi;
+	chip->read_buf(mtd, p, (mtd->oobsize - data_width));
+	p += (mtd->oobsize - data_width);
+
+	data_phase_addr = (unsigned long)chip->IO_ADDR_R;
+	data_phase_addr |= ZYNQ_NAND_CLEAR_CS;
+	chip->IO_ADDR_R = (void __iomem *)data_phase_addr;
+	chip->read_buf(mtd, p, data_width);
+
+	return 0;
+}
+
+/*
+ * zynq_nand_write_oob - [REPLACABLE] the most common OOB data write function
+ * @mtd:	mtd info structure
+ * @chip:	nand chip info structure
+ * @page:	page number to write
+ */
+static int zynq_nand_write_oob(struct mtd_info *mtd, struct nand_chip *chip,
+			     int page)
+{
+	int status = 0;
+	const u8 *buf = chip->oob_poi;
+	unsigned long data_width = 4;
+	unsigned long data_phase_addr = 0;
+
+	chip->cmdfunc(mtd, NAND_CMD_SEQIN, mtd->writesize, page);
+
+	chip->write_buf(mtd, buf, (mtd->oobsize - data_width));
+	buf += (mtd->oobsize - data_width);
+
+	data_phase_addr = (unsigned long)chip->IO_ADDR_W;
+	data_phase_addr |= ZYNQ_NAND_CLEAR_CS;
+	data_phase_addr |= (1 << END_CMD_VALID_SHIFT);
+	chip->IO_ADDR_W = (void __iomem *)data_phase_addr;
+	chip->write_buf(mtd, buf, data_width);
+
+	/* Send command to program the OOB data */
+	chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
+	status = chip->waitfunc(mtd, chip);
+
+	return status & NAND_STATUS_FAIL ? -EIO : 0;
+}
+
+/*
+ * zynq_nand_read_page_raw - [Intern] read raw page data without ecc
+ * @mtd:        mtd info structure
+ * @chip:       nand chip info structure
+ * @buf:        buffer to store read data
+ * @oob_required: must write chip->oob_poi to OOB
+ * @page:       page number to read
+ */
+static int zynq_nand_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
+				   u8 *buf,  int oob_required, int page)
+{
+	unsigned long data_width = 4;
+	unsigned long data_phase_addr = 0;
+	u8 *p;
+
+	chip->read_buf(mtd, buf, mtd->writesize);
+
+	p = chip->oob_poi;
+	chip->read_buf(mtd, p, (mtd->oobsize - data_width));
+	p += (mtd->oobsize - data_width);
+
+	data_phase_addr = (unsigned long)chip->IO_ADDR_R;
+	data_phase_addr |= ZYNQ_NAND_CLEAR_CS;
+	chip->IO_ADDR_R = (void __iomem *)data_phase_addr;
+
+	chip->read_buf(mtd, p, data_width);
+	return 0;
+}
+
+static int zynq_nand_read_page_raw_nooob(struct mtd_info *mtd,
+		struct nand_chip *chip, u8 *buf, int oob_required, int page)
+{
+	chip->read_buf(mtd, buf, mtd->writesize);
+	return 0;
+}
+
+static int zynq_nand_read_subpage_raw(struct mtd_info *mtd,
+				    struct nand_chip *chip, u32 data_offs,
+				    u32 readlen, u8 *buf)
+{
+	if (data_offs != 0) {
+		chip->cmdfunc(mtd, NAND_CMD_RNDOUT, data_offs, -1);
+		buf += data_offs;
+	}
+
+	chip->read_buf(mtd, buf, readlen);
+	return 0;
+}
+
+/*
+ * zynq_nand_write_page_raw - [Intern] raw page write function
+ * @mtd:        mtd info structure
+ * @chip:       nand chip info structure
+ * @buf:        data buffer
+ * @oob_required: must write chip->oob_poi to OOB
+ */
+static int zynq_nand_write_page_raw(struct mtd_info *mtd,
+	struct nand_chip *chip, const u8 *buf, int oob_required)
+{
+	unsigned long data_width = 4;
+	unsigned long data_phase_addr = 0;
+	u8 *p;
+
+	chip->write_buf(mtd, buf, mtd->writesize);
+
+	p = chip->oob_poi;
+	chip->write_buf(mtd, p, (mtd->oobsize - data_width));
+	p += (mtd->oobsize - data_width);
+
+	data_phase_addr = (unsigned long)chip->IO_ADDR_W;
+	data_phase_addr |= ZYNQ_NAND_CLEAR_CS;
+	data_phase_addr |= (1 << END_CMD_VALID_SHIFT);
+	chip->IO_ADDR_W = (void __iomem *)data_phase_addr;
+
+	chip->write_buf(mtd, p, data_width);
+
+	return 0;
+}
+
+/*
+ * nand_write_page_hwecc - Hardware ECC based page write function
+ * @mtd:	Pointer to the mtd info structure
+ * @chip:	Pointer to the NAND chip info structure
+ * @buf:	Pointer to the data buffer
+ * @oob_required: must write chip->oob_poi to OOB
+ *
+ * This functions writes data and hardware generated ECC values in to the page.
+ */
+static int zynq_nand_write_page_hwecc(struct mtd_info *mtd,
+	struct nand_chip *chip, const u8 *buf, int oob_required)
+{
+	int i, eccsize = chip->ecc.size;
+	int eccsteps = chip->ecc.steps;
+	u8 *ecc_calc = chip->buffers->ecccalc;
+	const u8 *p = buf;
+	u32 *eccpos = chip->ecc.layout->eccpos;
+	unsigned long data_phase_addr = 0;
+	unsigned long data_width = 4;
+	u8 *oob_ptr;
+
+	for (; (eccsteps - 1); eccsteps--) {
+		chip->write_buf(mtd, p, eccsize);
+		p += eccsize;
+	}
+	chip->write_buf(mtd, p, (eccsize - data_width));
+	p += (eccsize - data_width);
+
+	/* Set ECC Last bit to 1 */
+	data_phase_addr = (unsigned long) chip->IO_ADDR_W;
+	data_phase_addr |= ZYNQ_NAND_ECC_LAST;
+	chip->IO_ADDR_W = (void __iomem *)data_phase_addr;
+	chip->write_buf(mtd, p, data_width);
+
+	/* Wait for ECC to be calculated and read the error values */
+	p = buf;
+	chip->ecc.calculate(mtd, p, &ecc_calc[0]);
+
+	for (i = 0; i < chip->ecc.total; i++)
+		chip->oob_poi[eccpos[i]] = ~(ecc_calc[i]);
+
+	/* Clear ECC last bit */
+	data_phase_addr = (unsigned long)chip->IO_ADDR_W;
+	data_phase_addr &= ~ZYNQ_NAND_ECC_LAST;
+	chip->IO_ADDR_W = (void __iomem *)data_phase_addr;
+
+	/* Write the spare area with ECC bytes */
+	oob_ptr = chip->oob_poi;
+	chip->write_buf(mtd, oob_ptr, (mtd->oobsize - data_width));
+
+	data_phase_addr = (unsigned long)chip->IO_ADDR_W;
+	data_phase_addr |= ZYNQ_NAND_CLEAR_CS;
+	data_phase_addr |= (1 << END_CMD_VALID_SHIFT);
+	chip->IO_ADDR_W = (void __iomem *)data_phase_addr;
+	oob_ptr += (mtd->oobsize - data_width);
+	chip->write_buf(mtd, oob_ptr, data_width);
+
+	return 0;
+}
+
+/*
+ * zynq_nand_write_page_swecc - [REPLACABLE] software ecc based page
+ * write function
+ * @mtd:	mtd info structure
+ * @chip:	nand chip info structure
+ * @buf:	data buffer
+ * @oob_required: must write chip->oob_poi to OOB
+ */
+static int zynq_nand_write_page_swecc(struct mtd_info *mtd,
+	struct nand_chip *chip, const u8 *buf, int oob_required)
+{
+	int i, eccsize = chip->ecc.size;
+	int eccbytes = chip->ecc.bytes;
+	int eccsteps = chip->ecc.steps;
+	u8 *ecc_calc = chip->buffers->ecccalc;
+	const u8 *p = buf;
+	u32 *eccpos = chip->ecc.layout->eccpos;
+
+	/* Software ecc calculation */
+	for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
+		chip->ecc.calculate(mtd, p, &ecc_calc[i]);
+
+	for (i = 0; i < chip->ecc.total; i++)
+		chip->oob_poi[eccpos[i]] = ecc_calc[i];
+
+	return chip->ecc.write_page_raw(mtd, chip, buf, 1);
+}
+
+/*
+ * nand_read_page_hwecc - Hardware ECC based page read function
+ * @mtd:	Pointer to the mtd info structure
+ * @chip:	Pointer to the NAND chip info structure
+ * @buf:	Pointer to the buffer to store read data
+ * @oob_required: must write chip->oob_poi to OOB
+ * @page:	page number to read
+ *
+ * This functions reads data and checks the data integrity by comparing hardware
+ * generated ECC values and read ECC values from spare area.
+ *
+ * returns:	0 always and updates ECC operation status in to MTD structure
+ */
+static int zynq_nand_read_page_hwecc(struct mtd_info *mtd,
+	struct nand_chip *chip, u8 *buf, int oob_required, int page)
+{
+	int i, stat, eccsize = chip->ecc.size;
+	int eccbytes = chip->ecc.bytes;
+	int eccsteps = chip->ecc.steps;
+	u8 *p = buf;
+	u8 *ecc_calc = chip->buffers->ecccalc;
+	u8 *ecc_code = chip->buffers->ecccode;
+	u32 *eccpos = chip->ecc.layout->eccpos;
+	unsigned long data_phase_addr = 0;
+	unsigned long data_width = 4;
+	u8 *oob_ptr;
+
+	for (; (eccsteps - 1); eccsteps--) {
+		chip->read_buf(mtd, p, eccsize);
+		p += eccsize;
+	}
+	chip->read_buf(mtd, p, (eccsize - data_width));
+	p += (eccsize - data_width);
+
+	/* Set ECC Last bit to 1 */
+	data_phase_addr = (unsigned long)chip->IO_ADDR_R;
+	data_phase_addr |= ZYNQ_NAND_ECC_LAST;
+	chip->IO_ADDR_R = (void __iomem *)data_phase_addr;
+	chip->read_buf(mtd, p, data_width);
+
+	/* Read the calculated ECC value */
+	p = buf;
+	chip->ecc.calculate(mtd, p, &ecc_calc[0]);
+
+	/* Clear ECC last bit */
+	data_phase_addr = (unsigned long)chip->IO_ADDR_R;
+	data_phase_addr &= ~ZYNQ_NAND_ECC_LAST;
+	chip->IO_ADDR_R = (void __iomem *)data_phase_addr;
+
+	/* Read the stored ECC value */
+	oob_ptr = chip->oob_poi;
+	chip->read_buf(mtd, oob_ptr, (mtd->oobsize - data_width));
+
+	/* de-assert chip select */
+	data_phase_addr = (unsigned long)chip->IO_ADDR_R;
+	data_phase_addr |= ZYNQ_NAND_CLEAR_CS;
+	chip->IO_ADDR_R = (void __iomem *)data_phase_addr;
+
+	oob_ptr += (mtd->oobsize - data_width);
+	chip->read_buf(mtd, oob_ptr, data_width);
+
+	for (i = 0; i < chip->ecc.total; i++)
+		ecc_code[i] = ~(chip->oob_poi[eccpos[i]]);
+
+	eccsteps = chip->ecc.steps;
+	p = buf;
+
+	/* Check ECC error for all blocks and correct if it is correctable */
+	for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
+		stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
+		if (stat < 0)
+			mtd->ecc_stats.failed++;
+		else
+			mtd->ecc_stats.corrected += stat;
+	}
+	return 0;
+}
+
+/*
+ * zynq_nand_read_page_swecc - [REPLACABLE] software ecc based page
+ * read function
+ * @mtd:	mtd info structure
+ * @chip:	nand chip info structure
+ * @buf:	buffer to store read data
+ * @page:	page number to read
+ */
+static int zynq_nand_read_page_swecc(struct mtd_info *mtd,
+	struct nand_chip *chip, u8 *buf, int oob_required,  int page)
+{
+	int i, eccsize = chip->ecc.size;
+	int eccbytes = chip->ecc.bytes;
+	int eccsteps = chip->ecc.steps;
+	u8 *p = buf;
+	u8 *ecc_calc = chip->buffers->ecccalc;
+	u8 *ecc_code = chip->buffers->ecccode;
+	u32 *eccpos = chip->ecc.layout->eccpos;
+
+	chip->ecc.read_page_raw(mtd, chip, buf, 1, page);
+
+	for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
+		chip->ecc.calculate(mtd, p, &ecc_calc[i]);
+
+	for (i = 0; i < chip->ecc.total; i++)
+		ecc_code[i] = chip->oob_poi[eccpos[i]];
+
+	eccsteps = chip->ecc.steps;
+	p = buf;
+
+	for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
+		int stat;
+
+		stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
+		if (stat < 0)
+			mtd->ecc_stats.failed++;
+		else
+			mtd->ecc_stats.corrected += stat;
+	}
+	return 0;
+}
+
+/*
+ * zynq_nand_select_chip - Select the flash device
+ * @mtd:	Pointer to the mtd_info structure
+ * @chip:	Chip number to be selected
+ *
+ * This function is empty as the NAND controller handles chip select line
+ * internally based on the chip address passed in command and data phase.
+ */
+static void zynq_nand_select_chip(struct mtd_info *mtd, int chip)
+{
+	return;
+}
+
+/*
+ * zynq_nand_cmd_function - Send command to NAND device
+ * @mtd:	Pointer to the mtd_info structure
+ * @command:	The command to be sent to the flash device
+ * @column:	The column address for this command, -1 if none
+ * @page_addr:	The page address for this command, -1 if none
+ */
+static void zynq_nand_cmd_function(struct mtd_info *mtd, unsigned int command,
+				 int column, int page_addr)
+{
+	struct nand_chip *chip = mtd->priv;
+	const struct zynq_nand_command_format *curr_cmd = NULL;
+	struct zynq_nand_info *xnand;
+	void *cmd_addr;
+	unsigned long cmd_data = 0;
+	unsigned long cmd_phase_addr = 0;
+	unsigned long data_phase_addr = 0;
+	unsigned long end_cmd = 0;
+	unsigned long end_cmd_valid = 0;
+	unsigned long i;
+
+	xnand = (struct zynq_nand_info *)chip->priv;
+	if (xnand->end_cmd_pending) {
+		/* Check for end command if this command request is same as the
+		 * pending command then return
+		 */
+		if (xnand->end_cmd == command) {
+			xnand->end_cmd = 0;
+			xnand->end_cmd_pending = 0;
+			return;
+		}
+	}
+
+	/* Emulate NAND_CMD_READOOB for large page device */
+	if ((mtd->writesize > ZYNQ_NAND_ECC_SIZE) &&
+	    (command == NAND_CMD_READOOB)) {
+		column += mtd->writesize;
+		command = NAND_CMD_READ0;
+	}
+
+	/* Get the command format */
+	for (i = 0; (zynq_nand_commands[i].start_cmd != NAND_CMD_NONE ||
+		zynq_nand_commands[i].end_cmd != NAND_CMD_NONE); i++) {
+		if (command == zynq_nand_commands[i].start_cmd)
+			curr_cmd = &zynq_nand_commands[i];
+	}
+	if (curr_cmd == NULL)
+		return;
+
+	/* Clear interrupt */
+	writel((1 << 4), &zynq_nand_smc_base->cfr);
+
+	/* Get the command phase address */
+	if (curr_cmd->end_cmd_valid == ZYNQ_NAND_CMD_PHASE)
+		end_cmd_valid = 1;
+
+	if (curr_cmd->end_cmd == NAND_CMD_NONE)
+		end_cmd = 0x0;
+	else
+		end_cmd = curr_cmd->end_cmd;
+
+	cmd_phase_addr = (unsigned long)xnand->nand_base	|
+			(curr_cmd->addr_cycles << ADDR_CYCLES_SHIFT)	|
+			(end_cmd_valid << END_CMD_VALID_SHIFT)		|
+			(COMMAND_PHASE)					|
+			(end_cmd << END_CMD_SHIFT)			|
+			(curr_cmd->start_cmd << START_CMD_SHIFT);
+
+	cmd_addr = (void __iomem *)cmd_phase_addr;
+
+	/* Get the data phase address */
+	end_cmd_valid = 0;
+
+	data_phase_addr = (unsigned long)xnand->nand_base	|
+			(0x0 << CLEAR_CS_SHIFT)				|
+			(end_cmd_valid << END_CMD_VALID_SHIFT)		|
+			(DATA_PHASE)					|
+			(end_cmd << END_CMD_SHIFT)			|
+			(0x0 << ECC_LAST_SHIFT);
+
+	chip->IO_ADDR_R = (void  __iomem *)data_phase_addr;
+	chip->IO_ADDR_W = chip->IO_ADDR_R;
+
+	/* Command phase AXI Read & Write */
+	if (column != -1 && page_addr != -1) {
+		/* Adjust columns for 16 bit bus width */
+		if (chip->options & NAND_BUSWIDTH_16)
+			column >>= 1;
+		cmd_data = column;
+		if (mtd->writesize > ZYNQ_NAND_ECC_SIZE) {
+			cmd_data |= page_addr << 16;
+			/* Another address cycle for devices > 128MiB */
+			if (chip->chipsize > (128 << 20)) {
+				writel(cmd_data, cmd_addr);
+				cmd_data = (page_addr >> 16);
+			}
+		} else {
+			cmd_data |= page_addr << 8;
+		}
+	}
+	/* Erase */
+	else if (page_addr != -1)
+		cmd_data = page_addr;
+	/* Change read/write column, read id etc */
+	else if (column != -1) {
+		/* Adjust columns for 16 bit bus width */
+		if ((chip->options & NAND_BUSWIDTH_16) &&
+		    ((command == NAND_CMD_READ0) ||
+		     (command == NAND_CMD_SEQIN) ||
+		     (command == NAND_CMD_RNDOUT) ||
+		     (command == NAND_CMD_RNDIN)))
+			column >>= 1;
+		cmd_data = column;
+	} else
+		;
+
+	writel(cmd_data, cmd_addr);
+
+	if (curr_cmd->end_cmd_valid) {
+		xnand->end_cmd = curr_cmd->end_cmd;
+		xnand->end_cmd_pending = 1;
+	}
+
+	ndelay(100);
+
+	if ((command == NAND_CMD_READ0) ||
+	    (command == NAND_CMD_RESET) ||
+	    (command == NAND_CMD_PARAM) ||
+	    (command == NAND_CMD_GET_FEATURES)) {
+		while (!chip->dev_ready(mtd))
+				;
+		return;
+	}
+}
+
+/*
+ * zynq_nand_read_buf - read chip data into buffer
+ * @mtd:        MTD device structure
+ * @buf:        buffer to store date
+ * @len:        number of bytes to read
+ */
+static void zynq_nand_read_buf(struct mtd_info *mtd, u8 *buf, int len)
+{
+	struct nand_chip *chip = mtd->priv;
+	const u32 *nand = chip->IO_ADDR_R;
+
+	/* Make sure that buf is 32 bit aligned */
+	if (((int)buf & 0x3) != 0) {
+		if (((int)buf & 0x1) != 0) {
+			if (len) {
+				*buf = readb(nand);
+				buf += 1;
+				len--;
+			}
+		}
+
+		if (((int)buf & 0x3) != 0) {
+			if (len >= 2) {
+				*(u16 *)buf = readw(nand);
+				buf += 2;
+				len -= 2;
+			}
+		}
+	}
+
+	/* copy aligned data */
+	while (len >= 4) {
+		*(u32 *)buf = readl(nand);
+		buf += 4;
+		len -= 4;
+	}
+
+	/* mop up any remaining bytes */
+	if (len) {
+		if (len >= 2) {
+			*(u16 *)buf = readw(nand);
+			buf += 2;
+			len -= 2;
+		}
+
+		if (len)
+			*buf = readb(nand);
+	}
+}
+
+/*
+ * zynq_nand_write_buf - write buffer to chip
+ * @mtd:        MTD device structure
+ * @buf:        data buffer
+ * @len:        number of bytes to write
+ */
+static void zynq_nand_write_buf(struct mtd_info *mtd, const u8 *buf, int len)
+{
+	struct nand_chip *chip = mtd->priv;
+	const u32 *nand = chip->IO_ADDR_W;
+
+	/* Make sure that buf is 32 bit aligned */
+	if (((int)buf & 0x3) != 0) {
+		if (((int)buf & 0x1) != 0) {
+			if (len) {
+				writeb(*buf, nand);
+				buf += 1;
+				len--;
+			}
+		}
+
+		if (((int)buf & 0x3) != 0) {
+			if (len >= 2) {
+				writew(*(u16 *)buf, nand);
+				buf += 2;
+				len -= 2;
+			}
+		}
+	}
+
+	/* copy aligned data */
+	while (len >= 4) {
+		writel(*(u32 *)buf, nand);
+		buf += 4;
+		len -= 4;
+	}
+
+	/* mop up any remaining bytes */
+	if (len) {
+		if (len >= 2) {
+			writew(*(u16 *)buf, nand);
+			buf += 2;
+			len -= 2;
+		}
+
+		if (len)
+			writeb(*buf, nand);
+	}
+}
+
+/*
+ * zynq_nand_device_ready - Check device ready/busy line
+ * @mtd:	Pointer to the mtd_info structure
+ *
+ * returns:	0 on busy or 1 on ready state
+ */
+static int zynq_nand_device_ready(struct mtd_info *mtd)
+{
+	/* Check the raw_int_status1 bit */
+	if ((readl(&zynq_nand_smc_base->csr)) & 0x40) {
+		/* Clear the interrupt condition */
+		writel((1 << 4), &zynq_nand_smc_base->cfr);
+		return 1;
+	}
+	return 0;
+}
+
+static int zynq_nand_init(struct nand_chip *nand_chip, int devnum)
+{
+	struct zynq_nand_info *xnand;
+	struct mtd_info *mtd;
+	unsigned long ecc_page_size;
+	int err = -1;
+	u8 maf_id, dev_id, i;
+	u8 get_feature[4];
+	u8 set_feature[4] = {0x08, 0x00, 0x00, 0x00};
+	unsigned long ecc_cfg;
+	int ondie_ecc_enabled = 0;
+
+	xnand = calloc(1, sizeof(struct zynq_nand_info));
+	if (!xnand) {
+		printf("%s: failed to allocate\n", __func__);
+		goto free;
+	}
+
+	xnand->nand_base = (void *)ZYNQ_NAND_BASEADDR;
+	mtd = &nand_info[0];
+
+	nand_chip->priv = xnand;
+	mtd->priv = nand_chip;
+
+	/* Set address of NAND IO lines */
+	nand_chip->IO_ADDR_R = xnand->nand_base;
+	nand_chip->IO_ADDR_W = xnand->nand_base;
+
+	/* Set the driver entry points for MTD */
+	nand_chip->cmdfunc = zynq_nand_cmd_function;
+	nand_chip->dev_ready = zynq_nand_device_ready;
+	nand_chip->select_chip = zynq_nand_select_chip;
+
+	/* If we don't set this delay driver sets 20us by default */
+	nand_chip->chip_delay = 30;
+
+	/* Buffer read/write routines */
+	nand_chip->read_buf = zynq_nand_read_buf;
+	nand_chip->write_buf = zynq_nand_write_buf;
+
+	nand_chip->bbt_options = NAND_BBT_USE_FLASH;
+
+	/* Initialize the NAND flash interface on NAND controller */
+	if (zynq_nand_init_nand_flash(nand_chip->options) < 0) {
+		printf("%s: nand flash init failed\n", __func__);
+		goto free;
+	}
+
+	/* first scan to find the device and get the page size */
+	if (nand_scan_ident(mtd, 1, NULL)) {
+		printf("%s: nand_scan_ident failed\n", __func__);
+		goto fail;
+	}
+
+	/* Send the command for reading device ID */
+	nand_chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
+	nand_chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
+
+	/* Read manufacturer and device IDs */
+	maf_id = nand_chip->read_byte(mtd);
+	dev_id = nand_chip->read_byte(mtd);
+
+	if ((maf_id == 0x2c) && ((dev_id == 0xf1) ||
+				 (dev_id == 0xa1) || (dev_id == 0xb1) ||
+				 (dev_id == 0xaa) || (dev_id == 0xba) ||
+				 (dev_id == 0xda) || (dev_id == 0xca) ||
+				 (dev_id == 0xac) || (dev_id == 0xbc) ||
+				 (dev_id == 0xdc) || (dev_id == 0xcc) ||
+				 (dev_id == 0xa3) || (dev_id == 0xb3) ||
+				 (dev_id == 0xd3) || (dev_id == 0xc3))) {
+		nand_chip->cmdfunc(mtd, NAND_CMD_SET_FEATURES,
+						ONDIE_ECC_FEATURE_ADDR, -1);
+
+		for (i = 0; i < 4; i++)
+			writeb(set_feature[i], nand_chip->IO_ADDR_W);
+
+		/* wait for 1us after writing data with SET_FEATURES command */
+		ndelay(1000);
+
+		nand_chip->cmdfunc(mtd, NAND_CMD_GET_FEATURES,
+						ONDIE_ECC_FEATURE_ADDR, -1);
+		nand_chip->read_buf(mtd, get_feature, 4);
+
+		if (get_feature[0] & 0x08) {
+			debug("%s: OnDie ECC flash\n", __func__);
+			ondie_ecc_enabled = 1;
+		} else {
+			printf("%s: Unable to detect OnDie ECC\n", __func__);
+		}
+	}
+
+	if (ondie_ecc_enabled) {
+		/* bypass the controller ECC block */
+		ecc_cfg = readl(&zynq_nand_smc_base->emcr);
+		ecc_cfg &= ~0xc;
+		writel(ecc_cfg, &zynq_nand_smc_base->emcr);
+
+		/* The software ECC routines won't work
+		 * with the SMC controller
+		 */
+		nand_chip->ecc.mode = NAND_ECC_HW;
+		nand_chip->ecc.strength = 1;
+		nand_chip->ecc.read_page = zynq_nand_read_page_raw_nooob;
+		nand_chip->ecc.read_subpage = zynq_nand_read_subpage_raw;
+		nand_chip->ecc.write_page = zynq_nand_write_page_raw;
+		nand_chip->ecc.read_page_raw = zynq_nand_read_page_raw;
+		nand_chip->ecc.write_page_raw = zynq_nand_write_page_raw;
+		nand_chip->ecc.read_oob = zynq_nand_read_oob;
+		nand_chip->ecc.write_oob = zynq_nand_write_oob;
+		nand_chip->ecc.size = mtd->writesize;
+		nand_chip->ecc.bytes = 0;
+
+		/* NAND with on-die ECC supports subpage reads */
+		nand_chip->options |= NAND_SUBPAGE_READ;
+
+		/* On-Die ECC spare bytes offset 8 is used for ECC codes */
+		if (ondie_ecc_enabled) {
+			nand_chip->ecc.layout = &ondie_nand_oob_64;
+			/* Use the BBT pattern descriptors */
+			nand_chip->bbt_td = &bbt_main_descr;
+			nand_chip->bbt_md = &bbt_mirror_descr;
+		}
+	} else {
+		/* Hardware ECC generates 3 bytes ECC code for each 512 bytes */
+		nand_chip->ecc.mode = NAND_ECC_HW;
+		nand_chip->ecc.strength = 1;
+		nand_chip->ecc.size = ZYNQ_NAND_ECC_SIZE;
+		nand_chip->ecc.bytes = 3;
+		nand_chip->ecc.calculate = zynq_nand_calculate_hwecc;
+		nand_chip->ecc.correct = zynq_nand_correct_data;
+		nand_chip->ecc.hwctl = NULL;
+		nand_chip->ecc.read_page = zynq_nand_read_page_hwecc;
+		nand_chip->ecc.write_page = zynq_nand_write_page_hwecc;
+		nand_chip->ecc.read_page_raw = zynq_nand_read_page_raw;
+		nand_chip->ecc.write_page_raw = zynq_nand_write_page_raw;
+		nand_chip->ecc.read_oob = zynq_nand_read_oob;
+		nand_chip->ecc.write_oob = zynq_nand_write_oob;
+
+		switch (mtd->writesize) {
+		case 512:
+			ecc_page_size = 0x1;
+			/* Set the ECC memory config register */
+			writel((ZYNQ_NAND_ECC_CONFIG | ecc_page_size),
+			       &zynq_nand_smc_base->emcr);
+			break;
+		case 1024:
+			ecc_page_size = 0x2;
+			/* Set the ECC memory config register */
+			writel((ZYNQ_NAND_ECC_CONFIG | ecc_page_size),
+			       &zynq_nand_smc_base->emcr);
+			break;
+		case 2048:
+			ecc_page_size = 0x3;
+			/* Set the ECC memory config register */
+			writel((ZYNQ_NAND_ECC_CONFIG | ecc_page_size),
+			       &zynq_nand_smc_base->emcr);
+			break;
+		default:
+			/* The software ECC routines won't work with
+			 * the SMC controller
+			 */
+			nand_chip->ecc.mode = NAND_ECC_HW;
+			nand_chip->ecc.calculate = nand_calculate_ecc;
+			nand_chip->ecc.correct = nand_correct_data;
+			nand_chip->ecc.read_page = zynq_nand_read_page_swecc;
+			/* nand_chip->ecc.read_subpage = nand_read_subpage; */
+			nand_chip->ecc.write_page = zynq_nand_write_page_swecc;
+			nand_chip->ecc.read_page_raw = zynq_nand_read_page_raw;
+			nand_chip->ecc.write_page_raw =
+						zynq_nand_write_page_raw;
+			nand_chip->ecc.read_oob = zynq_nand_read_oob;
+			nand_chip->ecc.write_oob = zynq_nand_write_oob;
+			nand_chip->ecc.size = 256;
+			nand_chip->ecc.bytes = 3;
+			break;
+		}
+
+		if (mtd->oobsize == 16)
+			nand_chip->ecc.layout = &nand_oob_16;
+		else if (mtd->oobsize == 64)
+			nand_chip->ecc.layout = &nand_oob_64;
+		else
+			;
+	}
+
+	/* second phase scan */
+	if (nand_scan_tail(mtd)) {
+		printf("%s: nand_scan_tailfailed\n", __func__);
+		goto fail;
+	}
+
+	if (nand_register(devnum))
+		goto fail;
+
+	return 0;
+fail:
+	nand_release(mtd);
+free:
+	kfree(xnand);
+	return err;
+}
+
+static struct nand_chip nand_chip[CONFIG_SYS_MAX_NAND_DEVICE];
+
+void board_nand_init(void)
+{
+	struct nand_chip *nand = &nand_chip[0];
+
+	if (zynq_nand_init(nand, 0))
+		puts("ZYNQ NAND init failed\n");
+}