diff options
| -rw-r--r-- | drivers/mtd/nand/Makefile | 1 | ||||
| -rw-r--r-- | drivers/mtd/nand/mxs_nand.c | 1118 | 
2 files changed, 1119 insertions, 0 deletions
| diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile index 28bd3507d..36ee45430 100644 --- a/drivers/mtd/nand/Makefile +++ b/drivers/mtd/nand/Makefile @@ -54,6 +54,7 @@ COBJS-$(CONFIG_NAND_KIRKWOOD) += kirkwood_nand.o  COBJS-$(CONFIG_NAND_KMETER1) += kmeter1_nand.o  COBJS-$(CONFIG_NAND_MPC5121_NFC) += mpc5121_nfc.o  COBJS-$(CONFIG_NAND_MXC) += mxc_nand.o +COBJS-$(CONFIG_NAND_MXS) += mxs_nand.o  COBJS-$(CONFIG_NAND_NDFC) += ndfc.o  COBJS-$(CONFIG_NAND_NOMADIK) += nomadik.o  COBJS-$(CONFIG_NAND_S3C2410) += s3c2410_nand.o diff --git a/drivers/mtd/nand/mxs_nand.c b/drivers/mtd/nand/mxs_nand.c new file mode 100644 index 000000000..ce2a32687 --- /dev/null +++ b/drivers/mtd/nand/mxs_nand.c @@ -0,0 +1,1118 @@ +/* + * Freescale i.MX28 NAND flash driver + * + * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com> + * on behalf of DENX Software Engineering GmbH + * + * Based on code from LTIB: + * Freescale GPMI NFC NAND Flash Driver + * + * Copyright (C) 2010 Freescale Semiconductor, Inc. + * Copyright (C) 2008 Embedded Alley Solutions, Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * 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., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include <linux/mtd/mtd.h> +#include <linux/mtd/nand.h> +#include <linux/types.h> +#include <common.h> +#include <malloc.h> +#include <asm/errno.h> +#include <asm/io.h> +#include <asm/arch/clock.h> +#include <asm/arch/imx-regs.h> +#include <asm/arch/sys_proto.h> +#include <asm/arch/dma.h> + +#define	MXS_NAND_DMA_DESCRIPTOR_COUNT		4 + +#define	MXS_NAND_CHUNK_DATA_CHUNK_SIZE		512 +#define	MXS_NAND_METADATA_SIZE			10 + +#define	MXS_NAND_COMMAND_BUFFER_SIZE		32 + +#define	MXS_NAND_BCH_TIMEOUT			10000 + +struct mxs_nand_info { +	int		cur_chip; + +	uint32_t	cmd_queue_len; + +	uint8_t		*cmd_buf; +	uint8_t		*data_buf; +	uint8_t		*oob_buf; + +	uint8_t		marking_block_bad; +	uint8_t		raw_oob_mode; + +	/* Functions with altered behaviour */ +	int		(*hooked_read_oob)(struct mtd_info *mtd, +				loff_t from, struct mtd_oob_ops *ops); +	int		(*hooked_write_oob)(struct mtd_info *mtd, +				loff_t to, struct mtd_oob_ops *ops); +	int		(*hooked_block_markbad)(struct mtd_info *mtd, +				loff_t ofs); + +	/* DMA descriptors */ +	struct mxs_dma_desc	**desc; +	uint32_t		desc_index; +}; + +struct nand_ecclayout fake_ecc_layout; + +static struct mxs_dma_desc *mxs_nand_get_dma_desc(struct mxs_nand_info *info) +{ +	struct mxs_dma_desc *desc; + +	if (info->desc_index >= MXS_NAND_DMA_DESCRIPTOR_COUNT) { +		printf("MXS NAND: Too many DMA descriptors requested\n"); +		return NULL; +	} + +	desc = info->desc[info->desc_index]; +	info->desc_index++; + +	return desc; +} + +static void mxs_nand_return_dma_descs(struct mxs_nand_info *info) +{ +	int i; +	struct mxs_dma_desc *desc; + +	for (i = 0; i < info->desc_index; i++) { +		desc = info->desc[i]; +		memset(desc, 0, sizeof(struct mxs_dma_desc)); +		desc->address = (dma_addr_t)desc; +	} + +	info->desc_index = 0; +} + +static uint32_t mxs_nand_ecc_chunk_cnt(uint32_t page_data_size) +{ +	return page_data_size / MXS_NAND_CHUNK_DATA_CHUNK_SIZE; +} + +static uint32_t mxs_nand_ecc_size_in_bits(uint32_t ecc_strength) +{ +	return ecc_strength * 13; +} + +static uint32_t mxs_nand_aux_status_offset(void) +{ +	return (MXS_NAND_METADATA_SIZE + 0x3) & ~0x3; +} + +static inline uint32_t mxs_nand_get_ecc_strength(uint32_t page_data_size, +						uint32_t page_oob_size) +{ +	if (page_data_size == 2048) +		return 8; + +	if (page_data_size == 4096) { +		if (page_oob_size == 128) +			return 8; + +		if (page_oob_size == 218) +			return 16; +	} + +	return 0; +} + +static inline uint32_t mxs_nand_get_mark_offset(uint32_t page_data_size, +						uint32_t ecc_strength) +{ +	uint32_t chunk_data_size_in_bits; +	uint32_t chunk_ecc_size_in_bits; +	uint32_t chunk_total_size_in_bits; +	uint32_t block_mark_chunk_number; +	uint32_t block_mark_chunk_bit_offset; +	uint32_t block_mark_bit_offset; + +	chunk_data_size_in_bits = MXS_NAND_CHUNK_DATA_CHUNK_SIZE * 8; +	chunk_ecc_size_in_bits  = mxs_nand_ecc_size_in_bits(ecc_strength); + +	chunk_total_size_in_bits = +			chunk_data_size_in_bits + chunk_ecc_size_in_bits; + +	/* Compute the bit offset of the block mark within the physical page. */ +	block_mark_bit_offset = page_data_size * 8; + +	/* Subtract the metadata bits. */ +	block_mark_bit_offset -= MXS_NAND_METADATA_SIZE * 8; + +	/* +	 * Compute the chunk number (starting at zero) in which the block mark +	 * appears. +	 */ +	block_mark_chunk_number = +			block_mark_bit_offset / chunk_total_size_in_bits; + +	/* +	 * Compute the bit offset of the block mark within its chunk, and +	 * validate it. +	 */ +	block_mark_chunk_bit_offset = block_mark_bit_offset - +			(block_mark_chunk_number * chunk_total_size_in_bits); + +	if (block_mark_chunk_bit_offset > chunk_data_size_in_bits) +		return 1; + +	/* +	 * Now that we know the chunk number in which the block mark appears, +	 * we can subtract all the ECC bits that appear before it. +	 */ +	block_mark_bit_offset -= +		block_mark_chunk_number * chunk_ecc_size_in_bits; + +	return block_mark_bit_offset; +} + +static uint32_t mxs_nand_mark_byte_offset(struct mtd_info *mtd) +{ +	uint32_t ecc_strength; +	ecc_strength = mxs_nand_get_ecc_strength(mtd->writesize, mtd->oobsize); +	return mxs_nand_get_mark_offset(mtd->writesize, ecc_strength) >> 3; +} + +static uint32_t mxs_nand_mark_bit_offset(struct mtd_info *mtd) +{ +	uint32_t ecc_strength; +	ecc_strength = mxs_nand_get_ecc_strength(mtd->writesize, mtd->oobsize); +	return mxs_nand_get_mark_offset(mtd->writesize, ecc_strength) & 0x7; +} + +/* + * Wait for BCH complete IRQ and clear the IRQ + */ +static int mxs_nand_wait_for_bch_complete(void) +{ +	struct mx28_bch_regs *bch_regs = (struct mx28_bch_regs *)MXS_BCH_BASE; +	int timeout = MXS_NAND_BCH_TIMEOUT; +	int ret; + +	ret = mx28_wait_mask_set(&bch_regs->hw_bch_ctrl_reg, +		BCH_CTRL_COMPLETE_IRQ, timeout); + +	writel(BCH_CTRL_COMPLETE_IRQ, &bch_regs->hw_bch_ctrl_clr); + +	return ret; +} + +/* + * This is the function that we install in the cmd_ctrl function pointer of the + * owning struct nand_chip. The only functions in the reference implementation + * that use these functions pointers are cmdfunc and select_chip. + * + * In this driver, we implement our own select_chip, so this function will only + * be called by the reference implementation's cmdfunc. For this reason, we can + * ignore the chip enable bit and concentrate only on sending bytes to the NAND + * Flash. + */ +static void mxs_nand_cmd_ctrl(struct mtd_info *mtd, int data, unsigned int ctrl) +{ +	struct nand_chip *nand = mtd->priv; +	struct mxs_nand_info *nand_info = nand->priv; +	struct mxs_dma_desc *d; +	uint32_t channel = MXS_DMA_CHANNEL_AHB_APBH_GPMI0 + nand_info->cur_chip; +	int ret; + +	/* +	 * If this condition is true, something is _VERY_ wrong in MTD +	 * subsystem! +	 */ +	if (nand_info->cmd_queue_len == MXS_NAND_COMMAND_BUFFER_SIZE) { +		printf("MXS NAND: Command queue too long\n"); +		return; +	} + +	/* +	 * Every operation begins with a command byte and a series of zero or +	 * more address bytes. These are distinguished by either the Address +	 * Latch Enable (ALE) or Command Latch Enable (CLE) signals being +	 * asserted. When MTD is ready to execute the command, it will +	 * deasert both latch enables. +	 * +	 * Rather than run a separate DMA operation for every single byte, we +	 * queue them up and run a single DMA operation for the entire series +	 * of command and data bytes. +	 */ +	if (ctrl & (NAND_ALE | NAND_CLE)) { +		if (data != NAND_CMD_NONE) +			nand_info->cmd_buf[nand_info->cmd_queue_len++] = data; +		return; +	} + +	/* +	 * If control arrives here, MTD has deasserted both the ALE and CLE, +	 * which means it's ready to run an operation. Check if we have any +	 * bytes to send. +	 */ +	if (nand_info->cmd_queue_len == 0) +		return; + +	/* Compile the DMA descriptor -- a descriptor that sends command. */ +	d = mxs_nand_get_dma_desc(nand_info); +	d->cmd.data = +		MXS_DMA_DESC_COMMAND_DMA_READ | MXS_DMA_DESC_IRQ | +		MXS_DMA_DESC_CHAIN | MXS_DMA_DESC_DEC_SEM | +		MXS_DMA_DESC_WAIT4END | (3 << MXS_DMA_DESC_PIO_WORDS_OFFSET) | +		(nand_info->cmd_queue_len << MXS_DMA_DESC_BYTES_OFFSET); + +	d->cmd.address = (dma_addr_t)nand_info->cmd_buf; + +	d->cmd.pio_words[0] = +		GPMI_CTRL0_COMMAND_MODE_WRITE | +		GPMI_CTRL0_WORD_LENGTH | +		(nand_info->cur_chip << GPMI_CTRL0_CS_OFFSET) | +		GPMI_CTRL0_ADDRESS_NAND_CLE | +		GPMI_CTRL0_ADDRESS_INCREMENT | +		nand_info->cmd_queue_len; + +	mxs_dma_desc_append(channel, d); + +	/* Execute the DMA chain. */ +	ret = mxs_dma_go(channel); +	if (ret) +		printf("MXS NAND: Error sending command\n"); + +	mxs_nand_return_dma_descs(nand_info); + +	/* Reset the command queue. */ +	nand_info->cmd_queue_len = 0; +} + +/* + * Test if the NAND flash is ready. + */ +static int mxs_nand_device_ready(struct mtd_info *mtd) +{ +	struct nand_chip *chip = mtd->priv; +	struct mxs_nand_info *nand_info = chip->priv; +	struct mx28_gpmi_regs *gpmi_regs = +		(struct mx28_gpmi_regs *)MXS_GPMI_BASE; +	uint32_t tmp; + +	tmp = readl(&gpmi_regs->hw_gpmi_stat); +	tmp >>= (GPMI_STAT_READY_BUSY_OFFSET + nand_info->cur_chip); + +	return tmp & 1; +} + +/* + * Select the NAND chip. + */ +static void mxs_nand_select_chip(struct mtd_info *mtd, int chip) +{ +	struct nand_chip *nand = mtd->priv; +	struct mxs_nand_info *nand_info = nand->priv; + +	nand_info->cur_chip = chip; +} + +/* + * Handle block mark swapping. + * + * Note that, when this function is called, it doesn't know whether it's + * swapping the block mark, or swapping it *back* -- but it doesn't matter + * because the the operation is the same. + */ +static void mxs_nand_swap_block_mark(struct mtd_info *mtd, +					uint8_t *data_buf, uint8_t *oob_buf) +{ +	uint32_t bit_offset; +	uint32_t buf_offset; + +	uint32_t src; +	uint32_t dst; + +	bit_offset = mxs_nand_mark_bit_offset(mtd); +	buf_offset = mxs_nand_mark_byte_offset(mtd); + +	/* +	 * Get the byte from the data area that overlays the block mark. Since +	 * the ECC engine applies its own view to the bits in the page, the +	 * physical block mark won't (in general) appear on a byte boundary in +	 * the data. +	 */ +	src = data_buf[buf_offset] >> bit_offset; +	src |= data_buf[buf_offset + 1] << (8 - bit_offset); + +	dst = oob_buf[0]; + +	oob_buf[0] = src; + +	data_buf[buf_offset] &= ~(0xff << bit_offset); +	data_buf[buf_offset + 1] &= 0xff << bit_offset; + +	data_buf[buf_offset] |= dst << bit_offset; +	data_buf[buf_offset + 1] |= dst >> (8 - bit_offset); +} + +/* + * Read data from NAND. + */ +static void mxs_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int length) +{ +	struct nand_chip *nand = mtd->priv; +	struct mxs_nand_info *nand_info = nand->priv; +	struct mxs_dma_desc *d; +	uint32_t channel = MXS_DMA_CHANNEL_AHB_APBH_GPMI0 + nand_info->cur_chip; +	int ret; + +	if (length > NAND_MAX_PAGESIZE) { +		printf("MXS NAND: DMA buffer too big\n"); +		return; +	} + +	if (!buf) { +		printf("MXS NAND: DMA buffer is NULL\n"); +		return; +	} + +	/* Compile the DMA descriptor - a descriptor that reads data. */ +	d = mxs_nand_get_dma_desc(nand_info); +	d->cmd.data = +		MXS_DMA_DESC_COMMAND_DMA_WRITE | MXS_DMA_DESC_IRQ | +		MXS_DMA_DESC_DEC_SEM | MXS_DMA_DESC_WAIT4END | +		(1 << MXS_DMA_DESC_PIO_WORDS_OFFSET) | +		(length << MXS_DMA_DESC_BYTES_OFFSET); + +	d->cmd.address = (dma_addr_t)nand_info->data_buf; + +	d->cmd.pio_words[0] = +		GPMI_CTRL0_COMMAND_MODE_READ | +		GPMI_CTRL0_WORD_LENGTH | +		(nand_info->cur_chip << GPMI_CTRL0_CS_OFFSET) | +		GPMI_CTRL0_ADDRESS_NAND_DATA | +		length; + +	mxs_dma_desc_append(channel, d); + +	/* +	 * A DMA descriptor that waits for the command to end and the chip to +	 * become ready. +	 * +	 * I think we actually should *not* be waiting for the chip to become +	 * ready because, after all, we don't care. I think the original code +	 * did that and no one has re-thought it yet. +	 */ +	d = mxs_nand_get_dma_desc(nand_info); +	d->cmd.data = +		MXS_DMA_DESC_COMMAND_NO_DMAXFER | MXS_DMA_DESC_IRQ | +		MXS_DMA_DESC_NAND_WAIT_4_READY | MXS_DMA_DESC_DEC_SEM | +		MXS_DMA_DESC_WAIT4END | (4 << MXS_DMA_DESC_PIO_WORDS_OFFSET); + +	d->cmd.address = 0; + +	d->cmd.pio_words[0] = +		GPMI_CTRL0_COMMAND_MODE_WAIT_FOR_READY | +		GPMI_CTRL0_WORD_LENGTH | +		(nand_info->cur_chip << GPMI_CTRL0_CS_OFFSET) | +		GPMI_CTRL0_ADDRESS_NAND_DATA; + +	mxs_dma_desc_append(channel, d); + +	/* Execute the DMA chain. */ +	ret = mxs_dma_go(channel); +	if (ret) { +		printf("MXS NAND: DMA read error\n"); +		goto rtn; +	} + +	memcpy(buf, nand_info->data_buf, length); + +rtn: +	mxs_nand_return_dma_descs(nand_info); +} + +/* + * Write data to NAND. + */ +static void mxs_nand_write_buf(struct mtd_info *mtd, const uint8_t *buf, +				int length) +{ +	struct nand_chip *nand = mtd->priv; +	struct mxs_nand_info *nand_info = nand->priv; +	struct mxs_dma_desc *d; +	uint32_t channel = MXS_DMA_CHANNEL_AHB_APBH_GPMI0 + nand_info->cur_chip; +	int ret; + +	if (length > NAND_MAX_PAGESIZE) { +		printf("MXS NAND: DMA buffer too big\n"); +		return; +	} + +	if (!buf) { +		printf("MXS NAND: DMA buffer is NULL\n"); +		return; +	} + +	memcpy(nand_info->data_buf, buf, length); + +	/* Compile the DMA descriptor - a descriptor that writes data. */ +	d = mxs_nand_get_dma_desc(nand_info); +	d->cmd.data = +		MXS_DMA_DESC_COMMAND_DMA_READ | MXS_DMA_DESC_IRQ | +		MXS_DMA_DESC_DEC_SEM | MXS_DMA_DESC_WAIT4END | +		(4 << MXS_DMA_DESC_PIO_WORDS_OFFSET) | +		(length << MXS_DMA_DESC_BYTES_OFFSET); + +	d->cmd.address = (dma_addr_t)nand_info->data_buf; + +	d->cmd.pio_words[0] = +		GPMI_CTRL0_COMMAND_MODE_WRITE | +		GPMI_CTRL0_WORD_LENGTH | +		(nand_info->cur_chip << GPMI_CTRL0_CS_OFFSET) | +		GPMI_CTRL0_ADDRESS_NAND_DATA | +		length; + +	mxs_dma_desc_append(channel, d); + +	/* Execute the DMA chain. */ +	ret = mxs_dma_go(channel); +	if (ret) +		printf("MXS NAND: DMA write error\n"); + +	mxs_nand_return_dma_descs(nand_info); +} + +/* + * Read a single byte from NAND. + */ +static uint8_t mxs_nand_read_byte(struct mtd_info *mtd) +{ +	uint8_t buf; +	mxs_nand_read_buf(mtd, &buf, 1); +	return buf; +} + +/* + * Read a page from NAND. + */ +static int mxs_nand_ecc_read_page(struct mtd_info *mtd, struct nand_chip *nand, +					uint8_t *buf, int page) +{ +	struct mxs_nand_info *nand_info = nand->priv; +	struct mxs_dma_desc *d; +	uint32_t channel = MXS_DMA_CHANNEL_AHB_APBH_GPMI0 + nand_info->cur_chip; +	uint32_t corrected = 0, failed = 0; +	uint8_t	*status; +	int i, ret; + +	/* Compile the DMA descriptor - wait for ready. */ +	d = mxs_nand_get_dma_desc(nand_info); +	d->cmd.data = +		MXS_DMA_DESC_COMMAND_NO_DMAXFER | MXS_DMA_DESC_CHAIN | +		MXS_DMA_DESC_NAND_WAIT_4_READY | MXS_DMA_DESC_WAIT4END | +		(1 << MXS_DMA_DESC_PIO_WORDS_OFFSET); + +	d->cmd.address = 0; + +	d->cmd.pio_words[0] = +		GPMI_CTRL0_COMMAND_MODE_WAIT_FOR_READY | +		GPMI_CTRL0_WORD_LENGTH | +		(nand_info->cur_chip << GPMI_CTRL0_CS_OFFSET) | +		GPMI_CTRL0_ADDRESS_NAND_DATA; + +	mxs_dma_desc_append(channel, d); + +	/* Compile the DMA descriptor - enable the BCH block and read. */ +	d = mxs_nand_get_dma_desc(nand_info); +	d->cmd.data = +		MXS_DMA_DESC_COMMAND_NO_DMAXFER | MXS_DMA_DESC_CHAIN | +		MXS_DMA_DESC_WAIT4END |	(6 << MXS_DMA_DESC_PIO_WORDS_OFFSET); + +	d->cmd.address = 0; + +	d->cmd.pio_words[0] = +		GPMI_CTRL0_COMMAND_MODE_READ | +		GPMI_CTRL0_WORD_LENGTH | +		(nand_info->cur_chip << GPMI_CTRL0_CS_OFFSET) | +		GPMI_CTRL0_ADDRESS_NAND_DATA | +		(mtd->writesize + mtd->oobsize); +	d->cmd.pio_words[1] = 0; +	d->cmd.pio_words[2] = +		GPMI_ECCCTRL_ENABLE_ECC | +		GPMI_ECCCTRL_ECC_CMD_DECODE | +		GPMI_ECCCTRL_BUFFER_MASK_BCH_PAGE; +	d->cmd.pio_words[3] = mtd->writesize + mtd->oobsize; +	d->cmd.pio_words[4] = (dma_addr_t)nand_info->data_buf; +	d->cmd.pio_words[5] = (dma_addr_t)nand_info->oob_buf; + +	mxs_dma_desc_append(channel, d); + +	/* Compile the DMA descriptor - disable the BCH block. */ +	d = mxs_nand_get_dma_desc(nand_info); +	d->cmd.data = +		MXS_DMA_DESC_COMMAND_NO_DMAXFER | MXS_DMA_DESC_CHAIN | +		MXS_DMA_DESC_NAND_WAIT_4_READY | MXS_DMA_DESC_WAIT4END | +		(3 << MXS_DMA_DESC_PIO_WORDS_OFFSET); + +	d->cmd.address = 0; + +	d->cmd.pio_words[0] = +		GPMI_CTRL0_COMMAND_MODE_WAIT_FOR_READY | +		GPMI_CTRL0_WORD_LENGTH | +		(nand_info->cur_chip << GPMI_CTRL0_CS_OFFSET) | +		GPMI_CTRL0_ADDRESS_NAND_DATA | +		(mtd->writesize + mtd->oobsize); +	d->cmd.pio_words[1] = 0; +	d->cmd.pio_words[2] = 0; + +	mxs_dma_desc_append(channel, d); + +	/* Compile the DMA descriptor - deassert the NAND lock and interrupt. */ +	d = mxs_nand_get_dma_desc(nand_info); +	d->cmd.data = +		MXS_DMA_DESC_COMMAND_NO_DMAXFER | MXS_DMA_DESC_IRQ | +		MXS_DMA_DESC_DEC_SEM; + +	d->cmd.address = 0; + +	mxs_dma_desc_append(channel, d); + +	/* Execute the DMA chain. */ +	ret = mxs_dma_go(channel); +	if (ret) { +		printf("MXS NAND: DMA read error\n"); +		goto rtn; +	} + +	ret = mxs_nand_wait_for_bch_complete(); +	if (ret) { +		printf("MXS NAND: BCH read timeout\n"); +		goto rtn; +	} + +	/* Read DMA completed, now do the mark swapping. */ +	mxs_nand_swap_block_mark(mtd, nand_info->data_buf, nand_info->oob_buf); + +	/* Loop over status bytes, accumulating ECC status. */ +	status = nand_info->oob_buf + mxs_nand_aux_status_offset(); +	for (i = 0; i < mxs_nand_ecc_chunk_cnt(mtd->writesize); i++) { +		if (status[i] == 0x00) +			continue; + +		if (status[i] == 0xff) +			continue; + +		if (status[i] == 0xfe) { +			failed++; +			continue; +		} + +		corrected += status[i]; +	} + +	/* Propagate ECC status to the owning MTD. */ +	mtd->ecc_stats.failed += failed; +	mtd->ecc_stats.corrected += corrected; + +	/* +	 * It's time to deliver the OOB bytes. See mxs_nand_ecc_read_oob() for +	 * details about our policy for delivering the OOB. +	 * +	 * We fill the caller's buffer with set bits, and then copy the block +	 * mark to the caller's buffer. Note that, if block mark swapping was +	 * necessary, it has already been done, so we can rely on the first +	 * byte of the auxiliary buffer to contain the block mark. +	 */ +	memset(nand->oob_poi, 0xff, mtd->oobsize); + +	nand->oob_poi[0] = nand_info->oob_buf[0]; + +	memcpy(buf, nand_info->data_buf, mtd->writesize); + +rtn: +	mxs_nand_return_dma_descs(nand_info); + +	return ret; +} + +/* + * Write a page to NAND. + */ +static void mxs_nand_ecc_write_page(struct mtd_info *mtd, +				struct nand_chip *nand, const uint8_t *buf) +{ +	struct mxs_nand_info *nand_info = nand->priv; +	struct mxs_dma_desc *d; +	uint32_t channel = MXS_DMA_CHANNEL_AHB_APBH_GPMI0 + nand_info->cur_chip; +	int ret; + +	memcpy(nand_info->data_buf, buf, mtd->writesize); +	memcpy(nand_info->oob_buf, nand->oob_poi, mtd->oobsize); + +	/* Handle block mark swapping. */ +	mxs_nand_swap_block_mark(mtd, nand_info->data_buf, nand_info->oob_buf); + +	/* Compile the DMA descriptor - write data. */ +	d = mxs_nand_get_dma_desc(nand_info); +	d->cmd.data = +		MXS_DMA_DESC_COMMAND_NO_DMAXFER | MXS_DMA_DESC_IRQ | +		MXS_DMA_DESC_DEC_SEM | MXS_DMA_DESC_WAIT4END | +		(6 << MXS_DMA_DESC_PIO_WORDS_OFFSET); + +	d->cmd.address = 0; + +	d->cmd.pio_words[0] = +		GPMI_CTRL0_COMMAND_MODE_WRITE | +		GPMI_CTRL0_WORD_LENGTH | +		(nand_info->cur_chip << GPMI_CTRL0_CS_OFFSET) | +		GPMI_CTRL0_ADDRESS_NAND_DATA; +	d->cmd.pio_words[1] = 0; +	d->cmd.pio_words[2] = +		GPMI_ECCCTRL_ENABLE_ECC | +		GPMI_ECCCTRL_ECC_CMD_ENCODE | +		GPMI_ECCCTRL_BUFFER_MASK_BCH_PAGE; +	d->cmd.pio_words[3] = (mtd->writesize + mtd->oobsize); +	d->cmd.pio_words[4] = (dma_addr_t)nand_info->data_buf; +	d->cmd.pio_words[5] = (dma_addr_t)nand_info->oob_buf; + +	mxs_dma_desc_append(channel, d); + +	/* Execute the DMA chain. */ +	ret = mxs_dma_go(channel); +	if (ret) { +		printf("MXS NAND: DMA write error\n"); +		goto rtn; +	} + +	ret = mxs_nand_wait_for_bch_complete(); +	if (ret) { +		printf("MXS NAND: BCH write timeout\n"); +		goto rtn; +	} + +rtn: +	mxs_nand_return_dma_descs(nand_info); +} + +/* + * Read OOB from NAND. + * + * This function is a veneer that replaces the function originally installed by + * the NAND Flash MTD code. + */ +static int mxs_nand_hook_read_oob(struct mtd_info *mtd, loff_t from, +					struct mtd_oob_ops *ops) +{ +	struct nand_chip *chip = mtd->priv; +	struct mxs_nand_info *nand_info = chip->priv; +	int ret; + +	if (ops->mode == MTD_OOB_RAW) +		nand_info->raw_oob_mode = 1; +	else +		nand_info->raw_oob_mode = 0; + +	ret = nand_info->hooked_read_oob(mtd, from, ops); + +	nand_info->raw_oob_mode = 0; + +	return ret; +} + +/* + * Write OOB to NAND. + * + * This function is a veneer that replaces the function originally installed by + * the NAND Flash MTD code. + */ +static int mxs_nand_hook_write_oob(struct mtd_info *mtd, loff_t to, +					struct mtd_oob_ops *ops) +{ +	struct nand_chip *chip = mtd->priv; +	struct mxs_nand_info *nand_info = chip->priv; +	int ret; + +	if (ops->mode == MTD_OOB_RAW) +		nand_info->raw_oob_mode = 1; +	else +		nand_info->raw_oob_mode = 0; + +	ret = nand_info->hooked_write_oob(mtd, to, ops); + +	nand_info->raw_oob_mode = 0; + +	return ret; +} + +/* + * Mark a block bad in NAND. + * + * This function is a veneer that replaces the function originally installed by + * the NAND Flash MTD code. + */ +static int mxs_nand_hook_block_markbad(struct mtd_info *mtd, loff_t ofs) +{ +	struct nand_chip *chip = mtd->priv; +	struct mxs_nand_info *nand_info = chip->priv; +	int ret; + +	nand_info->marking_block_bad = 1; + +	ret = nand_info->hooked_block_markbad(mtd, ofs); + +	nand_info->marking_block_bad = 0; + +	return ret; +} + +/* + * There are several places in this driver where we have to handle the OOB and + * block marks. This is the function where things are the most complicated, so + * this is where we try to explain it all. All the other places refer back to + * here. + * + * These are the rules, in order of decreasing importance: + * + * 1) Nothing the caller does can be allowed to imperil the block mark, so all + *    write operations take measures to protect it. + * + * 2) In read operations, the first byte of the OOB we return must reflect the + *    true state of the block mark, no matter where that block mark appears in + *    the physical page. + * + * 3) ECC-based read operations return an OOB full of set bits (since we never + *    allow ECC-based writes to the OOB, it doesn't matter what ECC-based reads + *    return). + * + * 4) "Raw" read operations return a direct view of the physical bytes in the + *    page, using the conventional definition of which bytes are data and which + *    are OOB. This gives the caller a way to see the actual, physical bytes + *    in the page, without the distortions applied by our ECC engine. + * + * What we do for this specific read operation depends on whether we're doing + * "raw" read, or an ECC-based read. + * + * It turns out that knowing whether we want an "ECC-based" or "raw" read is not + * easy. When reading a page, for example, the NAND Flash MTD code calls our + * ecc.read_page or ecc.read_page_raw function. Thus, the fact that MTD wants an + * ECC-based or raw view of the page is implicit in which function it calls + * (there is a similar pair of ECC-based/raw functions for writing). + * + * Since MTD assumes the OOB is not covered by ECC, there is no pair of + * ECC-based/raw functions for reading or or writing the OOB. The fact that the + * caller wants an ECC-based or raw view of the page is not propagated down to + * this driver. + * + * Since our OOB *is* covered by ECC, we need this information. So, we hook the + * ecc.read_oob and ecc.write_oob function pointers in the owning + * struct mtd_info with our own functions. These hook functions set the + * raw_oob_mode field so that, when control finally arrives here, we'll know + * what to do. + */ +static int mxs_nand_ecc_read_oob(struct mtd_info *mtd, struct nand_chip *nand, +				int page, int cmd) +{ +	struct mxs_nand_info *nand_info = nand->priv; + +	/* +	 * First, fill in the OOB buffer. If we're doing a raw read, we need to +	 * get the bytes from the physical page. If we're not doing a raw read, +	 * we need to fill the buffer with set bits. +	 */ +	if (nand_info->raw_oob_mode) { +		/* +		 * If control arrives here, we're doing a "raw" read. Send the +		 * command to read the conventional OOB and read it. +		 */ +		nand->cmdfunc(mtd, NAND_CMD_READ0, mtd->writesize, page); +		nand->read_buf(mtd, nand->oob_poi, mtd->oobsize); +	} else { +		/* +		 * If control arrives here, we're not doing a "raw" read. Fill +		 * the OOB buffer with set bits and correct the block mark. +		 */ +		memset(nand->oob_poi, 0xff, mtd->oobsize); + +		nand->cmdfunc(mtd, NAND_CMD_READ0, mtd->writesize, page); +		mxs_nand_read_buf(mtd, nand->oob_poi, 1); +	} + +	return 0; + +} + +/* + * Write OOB data to NAND. + */ +static int mxs_nand_ecc_write_oob(struct mtd_info *mtd, struct nand_chip *nand, +					int page) +{ +	struct mxs_nand_info *nand_info = nand->priv; +	uint8_t block_mark = 0; + +	/* +	 * There are fundamental incompatibilities between the i.MX GPMI NFC and +	 * the NAND Flash MTD model that make it essentially impossible to write +	 * the out-of-band bytes. +	 * +	 * We permit *ONE* exception. If the *intent* of writing the OOB is to +	 * mark a block bad, we can do that. +	 */ + +	if (!nand_info->marking_block_bad) { +		printf("NXS NAND: Writing OOB isn't supported\n"); +		return -EIO; +	} + +	/* Write the block mark. */ +	nand->cmdfunc(mtd, NAND_CMD_SEQIN, mtd->writesize, page); +	nand->write_buf(mtd, &block_mark, 1); +	nand->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1); + +	/* Check if it worked. */ +	if (nand->waitfunc(mtd, nand) & NAND_STATUS_FAIL) +		return -EIO; + +	return 0; +} + +/* + * Claims all blocks are good. + * + * In principle, this function is *only* called when the NAND Flash MTD system + * isn't allowed to keep an in-memory bad block table, so it is forced to ask + * the driver for bad block information. + * + * In fact, we permit the NAND Flash MTD system to have an in-memory BBT, so + * this function is *only* called when we take it away. + * + * Thus, this function is only called when we want *all* blocks to look good, + * so it *always* return success. + */ +static int mxs_nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip) +{ +	return 0; +} + +/* + * Nominally, the purpose of this function is to look for or create the bad + * block table. In fact, since the we call this function at the very end of + * the initialization process started by nand_scan(), and we doesn't have a + * more formal mechanism, we "hook" this function to continue init process. + * + * At this point, the physical NAND Flash chips have been identified and + * counted, so we know the physical geometry. This enables us to make some + * important configuration decisions. + * + * The return value of this function propogates directly back to this driver's + * call to nand_scan(). Anything other than zero will cause this driver to + * tear everything down and declare failure. + */ +static int mxs_nand_scan_bbt(struct mtd_info *mtd) +{ +	struct nand_chip *nand = mtd->priv; +	struct mxs_nand_info *nand_info = nand->priv; +	struct mx28_bch_regs *bch_regs = (struct mx28_bch_regs *)MXS_BCH_BASE; +	uint32_t tmp; + +	/* Configure BCH and set NFC geometry */ +	mx28_reset_block(&bch_regs->hw_bch_ctrl_reg); + +	/* Configure layout 0 */ +	tmp = (mxs_nand_ecc_chunk_cnt(mtd->writesize) - 1) +		<< BCH_FLASHLAYOUT0_NBLOCKS_OFFSET; +	tmp |= MXS_NAND_METADATA_SIZE << BCH_FLASHLAYOUT0_META_SIZE_OFFSET; +	tmp |= (mxs_nand_get_ecc_strength(mtd->writesize, mtd->oobsize) >> 1) +		<< BCH_FLASHLAYOUT0_ECC0_OFFSET; +	tmp |= MXS_NAND_CHUNK_DATA_CHUNK_SIZE; +	writel(tmp, &bch_regs->hw_bch_flash0layout0); + +	tmp = (mtd->writesize + mtd->oobsize) +		<< BCH_FLASHLAYOUT1_PAGE_SIZE_OFFSET; +	tmp |= (mxs_nand_get_ecc_strength(mtd->writesize, mtd->oobsize) >> 1) +		<< BCH_FLASHLAYOUT1_ECCN_OFFSET; +	tmp |= MXS_NAND_CHUNK_DATA_CHUNK_SIZE; +	writel(tmp, &bch_regs->hw_bch_flash0layout1); + +	/* Set *all* chip selects to use layout 0 */ +	writel(0, &bch_regs->hw_bch_layoutselect); + +	/* Enable BCH complete interrupt */ +	writel(BCH_CTRL_COMPLETE_IRQ_EN, &bch_regs->hw_bch_ctrl_set); + +	/* Hook some operations at the MTD level. */ +	if (mtd->read_oob != mxs_nand_hook_read_oob) { +		nand_info->hooked_read_oob = mtd->read_oob; +		mtd->read_oob = mxs_nand_hook_read_oob; +	} + +	if (mtd->write_oob != mxs_nand_hook_write_oob) { +		nand_info->hooked_write_oob = mtd->write_oob; +		mtd->write_oob = mxs_nand_hook_write_oob; +	} + +	if (mtd->block_markbad != mxs_nand_hook_block_markbad) { +		nand_info->hooked_block_markbad = mtd->block_markbad; +		mtd->block_markbad = mxs_nand_hook_block_markbad; +	} + +	/* We use the reference implementation for bad block management. */ +	return nand_default_bbt(mtd); +} + +/* + * Allocate DMA buffers + */ +int mxs_nand_alloc_buffers(struct mxs_nand_info *nand_info) +{ +	uint8_t *buf; +	const int size = NAND_MAX_PAGESIZE + NAND_MAX_OOBSIZE; + +	/* DMA buffers */ +	buf = memalign(MXS_DMA_ALIGNMENT, size); +	if (!buf) { +		printf("MXS NAND: Error allocating DMA buffers\n"); +		return -ENOMEM; +	} + +	memset(buf, 0, size); + +	nand_info->data_buf = buf; +	nand_info->oob_buf = buf + NAND_MAX_PAGESIZE; + +	/* Command buffers */ +	nand_info->cmd_buf = memalign(MXS_DMA_ALIGNMENT, +				MXS_NAND_COMMAND_BUFFER_SIZE); +	if (!nand_info->cmd_buf) { +		free(buf); +		printf("MXS NAND: Error allocating command buffers\n"); +		return -ENOMEM; +	} +	memset(nand_info->cmd_buf, 0, MXS_NAND_COMMAND_BUFFER_SIZE); +	nand_info->cmd_queue_len = 0; + +	return 0; +} + +/* + * Initializes the NFC hardware. + */ +int mxs_nand_init(struct mxs_nand_info *info) +{ +	struct mx28_gpmi_regs *gpmi_regs = +		(struct mx28_gpmi_regs *)MXS_GPMI_BASE; +	int i = 0; + +	info->desc = malloc(sizeof(struct mxs_dma_desc *) * +				MXS_NAND_DMA_DESCRIPTOR_COUNT); +	if (!info->desc) +		goto err1; + +	/* Allocate the DMA descriptors. */ +	for (i = 0; i < MXS_NAND_DMA_DESCRIPTOR_COUNT; i++) { +		info->desc[i] = mxs_dma_desc_alloc(); +		if (!info->desc[i]) +			goto err2; +	} + +	/* Init the DMA controller. */ +	mxs_dma_init(); + +	/* Reset the GPMI block. */ +	mx28_reset_block(&gpmi_regs->hw_gpmi_ctrl0_reg); + +	/* +	 * Choose NAND mode, set IRQ polarity, disable write protection and +	 * select BCH ECC. +	 */ +	clrsetbits_le32(&gpmi_regs->hw_gpmi_ctrl1, +			GPMI_CTRL1_GPMI_MODE, +			GPMI_CTRL1_ATA_IRQRDY_POLARITY | GPMI_CTRL1_DEV_RESET | +			GPMI_CTRL1_BCH_MODE); + +	return 0; + +err2: +	free(info->desc); +err1: +	for (--i; i >= 0; i--) +		mxs_dma_desc_free(info->desc[i]); +	printf("MXS NAND: Unable to allocate DMA descriptors\n"); +	return -ENOMEM; +} + +/*! + * This function is called during the driver binding process. + * + * @param   pdev  the device structure used to store device specific + *                information that is used by the suspend, resume and + *                remove functions + * + * @return  The function always returns 0. + */ +int board_nand_init(struct nand_chip *nand) +{ +	struct mxs_nand_info *nand_info; +	int err; + +	nand_info = malloc(sizeof(struct mxs_nand_info)); +	if (!nand_info) { +		printf("MXS NAND: Failed to allocate private data\n"); +		return -ENOMEM; +	} +	memset(nand_info, 0, sizeof(struct mxs_nand_info)); + +	err = mxs_nand_alloc_buffers(nand_info); +	if (err) +		goto err1; + +	err = mxs_nand_init(nand_info); +	if (err) +		goto err2; + +	memset(&fake_ecc_layout, 0, sizeof(fake_ecc_layout)); + +	nand->priv = nand_info; +	nand->options |= NAND_NO_SUBPAGE_WRITE; + +	nand->cmd_ctrl		= mxs_nand_cmd_ctrl; + +	nand->dev_ready		= mxs_nand_device_ready; +	nand->select_chip	= mxs_nand_select_chip; +	nand->block_bad		= mxs_nand_block_bad; +	nand->scan_bbt		= mxs_nand_scan_bbt; + +	nand->read_byte		= mxs_nand_read_byte; + +	nand->read_buf		= mxs_nand_read_buf; +	nand->write_buf		= mxs_nand_write_buf; + +	nand->ecc.read_page	= mxs_nand_ecc_read_page; +	nand->ecc.write_page	= mxs_nand_ecc_write_page; +	nand->ecc.read_oob	= mxs_nand_ecc_read_oob; +	nand->ecc.write_oob	= mxs_nand_ecc_write_oob; + +	nand->ecc.layout	= &fake_ecc_layout; +	nand->ecc.mode		= NAND_ECC_HW; +	nand->ecc.bytes		= 9; +	nand->ecc.size		= 512; + +	return 0; + +err2: +	free(nand_info->data_buf); +	free(nand_info->cmd_buf); +err1: +	free(nand_info); +	return err; +} |