Signed-off-by: Marek Vasut marek.vasut@gmail.com Cc: Scott Wood scottwood@freescale.com Cc: Stefano Babic sbabic@denx.de Cc: Wolfgang Denk wd@denx.de Cc: Detlev Zundel dzu@denx.de --- drivers/mtd/nand/Makefile | 1 + drivers/mtd/nand/mxs_nand.c | 1158 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 1159 insertions(+), 0 deletions(-) create mode 100644 drivers/mtd/nand/mxs_nand.c
V2: Update comments, drop inlines V3: Fix descriptor reclamation loop
diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile index b6a7886..aef0d56 100644 --- a/drivers/mtd/nand/Makefile +++ b/drivers/mtd/nand/Makefile @@ -49,6 +49,7 @@ 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 0000000..601f11b --- /dev/null +++ b/drivers/mtd/nand/mxs_nand.c @@ -0,0 +1,1158 @@ +/* + * 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 uint32_t mxs_nand_aux_size(uint32_t page_size) +{ + uint32_t aux_status_off = mxs_nand_aux_status_offset(); + uint32_t ecc_chunk_cnt = + (mxs_nand_ecc_chunk_cnt(page_size) + 0x3) & ~0x3; + + return ecc_chunk_cnt + aux_status_off; +} + +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 th 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 two questions: + * + * 1) Are we doing a "raw" read, or an ECC-based read? + * + * 2) Are we using block mark swapping or transcription? + * + * There are four cases, illustrated by the following Karnaugh map: + * + * | Raw | ECC-based | + * -------------+-------------------------+-------------------------+ + * | Read the conventional | | + * | OOB at the end of the | | + * Swapping | page and return it. It | | + * | contains exactly what | | + * | we want. | Read the block mark and | + * -------------+-------------------------+ return it in a buffer | + * | Read the conventional | full of set bits. | + * | OOB at the end of the | | + * | page and also the block | | + * Transcribing | mark in the metadata. | | + * | Copy the block mark | | + * | into the first byte of | | + * | the OOB. | | + * -------------+-------------------------+-------------------------+ + * + * Note that we break rule #4 in the Transcribing/Raw case because we're not + * giving an accurate view of the actual, physical bytes in the page (we're + * overwriting the block mark). That's OK because it's more important to follow + * rule #2. + * + * 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. + * + * We take away the in-memory BBT when the user sets the "ignorebad" parameter, + * which indicates that all blocks should be reported good. + * + * 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; +}