blob: bf9414fef1e91f0f95e15e7d5b315307d2e9eab4 [file] [log] [blame]
/*
* 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;
uint32_t data_buf_size;
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;
/*
* Cache management functions
*/
#ifndef CONFIG_SYS_DCACHE_OFF
static void mxs_nand_flush_data_buf(struct mxs_nand_info *info)
{
uint32_t addr = (uint32_t)info->data_buf;
flush_dcache_range(addr, addr + info->data_buf_size);
}
static void mxs_nand_inval_data_buf(struct mxs_nand_info *info)
{
uint32_t addr = (uint32_t)info->data_buf;
invalidate_dcache_range(addr, addr + info->data_buf_size);
}
static void mxs_nand_flush_cmd_buf(struct mxs_nand_info *info)
{
uint32_t addr = (uint32_t)info->cmd_buf;
flush_dcache_range(addr, addr + MXS_NAND_COMMAND_BUFFER_SIZE);
}
#else
static inline void mxs_nand_flush_data_buf(struct mxs_nand_info *info) {}
static inline void mxs_nand_inval_data_buf(struct mxs_nand_info *info) {}
static inline void mxs_nand_flush_cmd_buf(struct mxs_nand_info *info) {}
#endif
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 mxs_bch_regs *bch_regs = (struct mxs_bch_regs *)MXS_BCH_BASE;
int timeout = MXS_NAND_BCH_TIMEOUT;
int ret;
ret = mxs_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);
/* Flush caches */
mxs_nand_flush_cmd_buf(nand_info);
/* 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 mxs_gpmi_regs *gpmi_regs =
(struct mxs_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;
}
/* Invalidate caches */
mxs_nand_inval_data_buf(nand_info);
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);
/* Flush caches */
mxs_nand_flush_data_buf(nand_info);
/* 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;
}
/* Invalidate caches */
mxs_nand_inval_data_buf(nand_info);
/* 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);
/* Flush caches */
mxs_nand_flush_data_buf(nand_info);
/* 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 mxs_bch_regs *bch_regs = (struct mxs_bch_regs *)MXS_BCH_BASE;
uint32_t tmp;
/* Configure BCH and set NFC geometry */
mxs_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;
nand_info->data_buf_size = roundup(size, MXS_DMA_ALIGNMENT);
/* DMA buffers */
buf = memalign(MXS_DMA_ALIGNMENT, nand_info->data_buf_size);
if (!buf) {
printf("MXS NAND: Error allocating DMA buffers\n");
return -ENOMEM;
}
memset(buf, 0, nand_info->data_buf_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 mxs_gpmi_regs *gpmi_regs =
(struct mxs_gpmi_regs *)MXS_GPMI_BASE;
int i = 0, j;
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. */
for (j = MXS_DMA_CHANNEL_AHB_APBH_GPMI0;
j <= MXS_DMA_CHANNEL_AHB_APBH_GPMI7; j++) {
if (mxs_dma_init_channel(j))
goto err3;
}
/* Reset the GPMI block. */
mxs_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;
err3:
for (--j; j >= 0; j--)
mxs_dma_release(j);
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;
}