- 根目录:
- drivers
- mtd
- nand
- omap2.c
/*
* Copyright © 2004 Texas Instruments, Jian Zhang <jzhang@ti.com>
* Copyright © 2004 Micron Technology Inc.
* Copyright © 2004 David Brownell
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/jiffies.h>
#include <linux/sched.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <plat/dma.h>
#include <plat/gpmc.h>
#include <plat/nand.h>
#define DRIVER_NAME "omap2-nand"
#define OMAP_NAND_TIMEOUT_MS 5000
#define NAND_Ecc_P1e (1 << 0)
#define NAND_Ecc_P2e (1 << 1)
#define NAND_Ecc_P4e (1 << 2)
#define NAND_Ecc_P8e (1 << 3)
#define NAND_Ecc_P16e (1 << 4)
#define NAND_Ecc_P32e (1 << 5)
#define NAND_Ecc_P64e (1 << 6)
#define NAND_Ecc_P128e (1 << 7)
#define NAND_Ecc_P256e (1 << 8)
#define NAND_Ecc_P512e (1 << 9)
#define NAND_Ecc_P1024e (1 << 10)
#define NAND_Ecc_P2048e (1 << 11)
#define NAND_Ecc_P1o (1 << 16)
#define NAND_Ecc_P2o (1 << 17)
#define NAND_Ecc_P4o (1 << 18)
#define NAND_Ecc_P8o (1 << 19)
#define NAND_Ecc_P16o (1 << 20)
#define NAND_Ecc_P32o (1 << 21)
#define NAND_Ecc_P64o (1 << 22)
#define NAND_Ecc_P128o (1 << 23)
#define NAND_Ecc_P256o (1 << 24)
#define NAND_Ecc_P512o (1 << 25)
#define NAND_Ecc_P1024o (1 << 26)
#define NAND_Ecc_P2048o (1 << 27)
#define TF(value) (value ? 1 : 0)
#define P2048e(a) (TF(a & NAND_Ecc_P2048e) << 0)
#define P2048o(a) (TF(a & NAND_Ecc_P2048o) << 1)
#define P1e(a) (TF(a & NAND_Ecc_P1e) << 2)
#define P1o(a) (TF(a & NAND_Ecc_P1o) << 3)
#define P2e(a) (TF(a & NAND_Ecc_P2e) << 4)
#define P2o(a) (TF(a & NAND_Ecc_P2o) << 5)
#define P4e(a) (TF(a & NAND_Ecc_P4e) << 6)
#define P4o(a) (TF(a & NAND_Ecc_P4o) << 7)
#define P8e(a) (TF(a & NAND_Ecc_P8e) << 0)
#define P8o(a) (TF(a & NAND_Ecc_P8o) << 1)
#define P16e(a) (TF(a & NAND_Ecc_P16e) << 2)
#define P16o(a) (TF(a & NAND_Ecc_P16o) << 3)
#define P32e(a) (TF(a & NAND_Ecc_P32e) << 4)
#define P32o(a) (TF(a & NAND_Ecc_P32o) << 5)
#define P64e(a) (TF(a & NAND_Ecc_P64e) << 6)
#define P64o(a) (TF(a & NAND_Ecc_P64o) << 7)
#define P128e(a) (TF(a & NAND_Ecc_P128e) << 0)
#define P128o(a) (TF(a & NAND_Ecc_P128o) << 1)
#define P256e(a) (TF(a & NAND_Ecc_P256e) << 2)
#define P256o(a) (TF(a & NAND_Ecc_P256o) << 3)
#define P512e(a) (TF(a & NAND_Ecc_P512e) << 4)
#define P512o(a) (TF(a & NAND_Ecc_P512o) << 5)
#define P1024e(a) (TF(a & NAND_Ecc_P1024e) << 6)
#define P1024o(a) (TF(a & NAND_Ecc_P1024o) << 7)
#define P8e_s(a) (TF(a & NAND_Ecc_P8e) << 0)
#define P8o_s(a) (TF(a & NAND_Ecc_P8o) << 1)
#define P16e_s(a) (TF(a & NAND_Ecc_P16e) << 2)
#define P16o_s(a) (TF(a & NAND_Ecc_P16o) << 3)
#define P1e_s(a) (TF(a & NAND_Ecc_P1e) << 4)
#define P1o_s(a) (TF(a & NAND_Ecc_P1o) << 5)
#define P2e_s(a) (TF(a & NAND_Ecc_P2e) << 6)
#define P2o_s(a) (TF(a & NAND_Ecc_P2o) << 7)
#define P4e_s(a) (TF(a & NAND_Ecc_P4e) << 0)
#define P4o_s(a) (TF(a & NAND_Ecc_P4o) << 1)
static const char *part_probes[] = { "cmdlinepart", NULL };
/* oob info generated runtime depending on ecc algorithm and layout selected */
static struct nand_ecclayout omap_oobinfo;
/* Define some generic bad / good block scan pattern which are used
* while scanning a device for factory marked good / bad blocks
*/
static uint8_t scan_ff_pattern[] = { 0xff };
static struct nand_bbt_descr bb_descrip_flashbased = {
.options = NAND_BBT_SCANEMPTY | NAND_BBT_SCANALLPAGES,
.offs = 0,
.len = 1,
.pattern = scan_ff_pattern,
};
struct omap_nand_info {
struct nand_hw_control controller;
struct omap_nand_platform_data *pdata;
struct mtd_info mtd;
struct mtd_partition *parts;
struct nand_chip nand;
struct platform_device *pdev;
int gpmc_cs;
unsigned long phys_base;
struct completion comp;
int dma_ch;
int gpmc_irq;
enum {
OMAP_NAND_IO_READ = 0, /* read */
OMAP_NAND_IO_WRITE, /* write */
} iomode;
u_char *buf;
int buf_len;
};
/**
* omap_hwcontrol - hardware specific access to control-lines
* @mtd: MTD device structure
* @cmd: command to device
* @ctrl:
* NAND_NCE: bit 0 -> don't care
* NAND_CLE: bit 1 -> Command Latch
* NAND_ALE: bit 2 -> Address Latch
*
* NOTE: boards may use different bits for these!!
*/
static void omap_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
{
struct omap_nand_info *info = container_of(mtd,
struct omap_nand_info, mtd);
if (cmd != NAND_CMD_NONE) {
if (ctrl & NAND_CLE)
gpmc_nand_write(info->gpmc_cs, GPMC_NAND_COMMAND, cmd);
else if (ctrl & NAND_ALE)
gpmc_nand_write(info->gpmc_cs, GPMC_NAND_ADDRESS, cmd);
else /* NAND_NCE */
gpmc_nand_write(info->gpmc_cs, GPMC_NAND_DATA, cmd);
}
}
/**
* omap_read_buf8 - read data from NAND controller into buffer
* @mtd: MTD device structure
* @buf: buffer to store date
* @len: number of bytes to read
*/
static void omap_read_buf8(struct mtd_info *mtd, u_char *buf, int len)
{
struct nand_chip *nand = mtd->priv;
ioread8_rep(nand->IO_ADDR_R, buf, len);
}
/**
* omap_write_buf8 - write buffer to NAND controller
* @mtd: MTD device structure
* @buf: data buffer
* @len: number of bytes to write
*/
static void omap_write_buf8(struct mtd_info *mtd, const u_char *buf, int len)
{
struct omap_nand_info *info = container_of(mtd,
struct omap_nand_info, mtd);
u_char *p = (u_char *)buf;
u32 status = 0;
while (len--) {
iowrite8(*p++, info->nand.IO_ADDR_W);
/* wait until buffer is available for write */
do {
status = gpmc_read_status(GPMC_STATUS_BUFFER);
} while (!status);
}
}
/**
* omap_read_buf16 - read data from NAND controller into buffer
* @mtd: MTD device structure
* @buf: buffer to store date
* @len: number of bytes to read
*/
static void omap_read_buf16(struct mtd_info *mtd, u_char *buf, int len)
{
struct nand_chip *nand = mtd->priv;
ioread16_rep(nand->IO_ADDR_R, buf, len / 2);
}
/**
* omap_write_buf16 - write buffer to NAND controller
* @mtd: MTD device structure
* @buf: data buffer
* @len: number of bytes to write
*/
static void omap_write_buf16(struct mtd_info *mtd, const u_char * buf, int len)
{
struct omap_nand_info *info = container_of(mtd,
struct omap_nand_info, mtd);
u16 *p = (u16 *) buf;
u32 status = 0;
/* FIXME try bursts of writesw() or DMA ... */
len >>= 1;
while (len--) {
iowrite16(*p++, info->nand.IO_ADDR_W);
/* wait until buffer is available for write */
do {
status = gpmc_read_status(GPMC_STATUS_BUFFER);
} while (!status);
}
}
/**
* omap_read_buf_pref - read data from NAND controller into buffer
* @mtd: MTD device structure
* @buf: buffer to store date
* @len: number of bytes to read
*/
static void omap_read_buf_pref(struct mtd_info *mtd, u_char *buf, int len)
{
struct omap_nand_info *info = container_of(mtd,
struct omap_nand_info, mtd);
uint32_t r_count = 0;
int ret = 0;
u32 *p = (u32 *)buf;
/* take care of subpage reads */
if (len % 4) {
if (info->nand.options & NAND_BUSWIDTH_16)
omap_read_buf16(mtd, buf, len % 4);
else
omap_read_buf8(mtd, buf, len % 4);
p = (u32 *) (buf + len % 4);
len -= len % 4;
}
/* configure and start prefetch transfer */
ret = gpmc_prefetch_enable(info->gpmc_cs,
PREFETCH_FIFOTHRESHOLD_MAX, 0x0, len, 0x0);
if (ret) {
/* PFPW engine is busy, use cpu copy method */
if (info->nand.options & NAND_BUSWIDTH_16)
omap_read_buf16(mtd, (u_char *)p, len);
else
omap_read_buf8(mtd, (u_char *)p, len);
} else {
do {
r_count = gpmc_read_status(GPMC_PREFETCH_FIFO_CNT);
r_count = r_count >> 2;
ioread32_rep(info->nand.IO_ADDR_R, p, r_count);
p += r_count;
len -= r_count << 2;
} while (len);
/* disable and stop the PFPW engine */
gpmc_prefetch_reset(info->gpmc_cs);
}
}
/**
* omap_write_buf_pref - write buffer to NAND controller
* @mtd: MTD device structure
* @buf: data buffer
* @len: number of bytes to write
*/
static void omap_write_buf_pref(struct mtd_info *mtd,
const u_char *buf, int len)
{
struct omap_nand_info *info = container_of(mtd,
struct omap_nand_info, mtd);
uint32_t w_count = 0;
int i = 0, ret = 0;
u16 *p = (u16 *)buf;
unsigned long tim, limit;
/* take care of subpage writes */
if (len % 2 != 0) {
writeb(*buf, info->nand.IO_ADDR_W);
p = (u16 *)(buf + 1);
len--;
}
/* configure and start prefetch transfer */
ret = gpmc_prefetch_enable(info->gpmc_cs,
PREFETCH_FIFOTHRESHOLD_MAX, 0x0, len, 0x1);
if (ret) {
/* PFPW engine is busy, use cpu copy method */
if (info->nand.options & NAND_BUSWIDTH_16)
omap_write_buf16(mtd, (u_char *)p, len);
else
omap_write_buf8(mtd, (u_char *)p, len);
} else {
while (len) {
w_count = gpmc_read_status(GPMC_PREFETCH_FIFO_CNT);
w_count = w_count >> 1;
for (i = 0; (i < w_count) && len; i++, len -= 2)
iowrite16(*p++, info->nand.IO_ADDR_W);
}
/* wait for data to flushed-out before reset the prefetch */
tim = 0;
limit = (loops_per_jiffy *
msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
while (gpmc_read_status(GPMC_PREFETCH_COUNT) && (tim++ < limit))
cpu_relax();
/* disable and stop the PFPW engine */
gpmc_prefetch_reset(info->gpmc_cs);
}
}
/*
* omap_nand_dma_cb: callback on the completion of dma transfer
* @lch: logical channel
* @ch_satuts: channel status
* @data: pointer to completion data structure
*/
static void omap_nand_dma_cb(int lch, u16 ch_status, void *data)
{
complete((struct completion *) data);
}
/*
* omap_nand_dma_transfer: configer and start dma transfer
* @mtd: MTD device structure
* @addr: virtual address in RAM of source/destination
* @len: number of data bytes to be transferred
* @is_write: flag for read/write operation
*/
static inline int omap_nand_dma_transfer(struct mtd_info *mtd, void *addr,
unsigned int len, int is_write)
{
struct omap_nand_info *info = container_of(mtd,
struct omap_nand_info, mtd);
enum dma_data_direction dir = is_write ? DMA_TO_DEVICE :
DMA_FROM_DEVICE;
dma_addr_t dma_addr;
int ret;
unsigned long tim, limit;
/* The fifo depth is 64 bytes max.
* But configure the FIFO-threahold to 32 to get a sync at each frame
* and frame length is 32 bytes.
*/
int buf_len = len >> 6;
if (addr >= high_memory) {
struct page *p1;
if (((size_t)addr & PAGE_MASK) !=
((size_t)(addr + len - 1) & PAGE_MASK))
goto out_copy;
p1 = vmalloc_to_page(addr);
if (!p1)
goto out_copy;
addr = page_address(p1) + ((size_t)addr & ~PAGE_MASK);
}
dma_addr = dma_map_single(&info->pdev->dev, addr, len, dir);
if (dma_mapping_error(&info->pdev->dev, dma_addr)) {
dev_err(&info->pdev->dev,
"Couldn't DMA map a %d byte buffer\n", len);
goto out_copy;
}
if (is_write) {
omap_set_dma_dest_params(info->dma_ch, 0, OMAP_DMA_AMODE_CONSTANT,
info->phys_base, 0, 0);
omap_set_dma_src_params(info->dma_ch, 0, OMAP_DMA_AMODE_POST_INC,
dma_addr, 0, 0);
omap_set_dma_transfer_params(info->dma_ch, OMAP_DMA_DATA_TYPE_S32,
0x10, buf_len, OMAP_DMA_SYNC_FRAME,
OMAP24XX_DMA_GPMC, OMAP_DMA_DST_SYNC);
} else {
omap_set_dma_src_params(info->dma_ch, 0, OMAP_DMA_AMODE_CONSTANT,
info->phys_base, 0, 0);
omap_set_dma_dest_params(info->dma_ch, 0, OMAP_DMA_AMODE_POST_INC,
dma_addr, 0, 0);
omap_set_dma_transfer_params(info->dma_ch, OMAP_DMA_DATA_TYPE_S32,
0x10, buf_len, OMAP_DMA_SYNC_FRAME,
OMAP24XX_DMA_GPMC, OMAP_DMA_SRC_SYNC);
}
/* configure and start prefetch transfer */
ret = gpmc_prefetch_enable(info->gpmc_cs,
PREFETCH_FIFOTHRESHOLD_MAX, 0x1, len, is_write);
if (ret)
/* PFPW engine is busy, use cpu copy method */
goto out_copy;
init_completion(&info->comp);
omap_start_dma(info->dma_ch);
/* setup and start DMA using dma_addr */
wait_for_completion(&info->comp);
tim = 0;
limit = (loops_per_jiffy * msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
while (gpmc_read_status(GPMC_PREFETCH_COUNT) && (tim++ < limit))
cpu_relax();
/* disable and stop the PFPW engine */
gpmc_prefetch_reset(info->gpmc_cs);
dma_unmap_single(&info->pdev->dev, dma_addr, len, dir);
return 0;
out_copy:
if (info->nand.options & NAND_BUSWIDTH_16)
is_write == 0 ? omap_read_buf16(mtd, (u_char *) addr, len)
: omap_write_buf16(mtd, (u_char *) addr, len);
else
is_write == 0 ? omap_read_buf8(mtd, (u_char *) addr, len)
: omap_write_buf8(mtd, (u_char *) addr, len);
return 0;
}
/**
* omap_read_buf_dma_pref - read data from NAND controller into buffer
* @mtd: MTD device structure
* @buf: buffer to store date
* @len: number of bytes to read
*/
static void omap_read_buf_dma_pref(struct mtd_info *mtd, u_char *buf, int len)
{
if (len <= mtd->oobsize)
omap_read_buf_pref(mtd, buf, len);
else
/* start transfer in DMA mode */
omap_nand_dma_transfer(mtd, buf, len, 0x0);
}
/**
* omap_write_buf_dma_pref - write buffer to NAND controller
* @mtd: MTD device structure
* @buf: data buffer
* @len: number of bytes to write
*/
static void omap_write_buf_dma_pref(struct mtd_info *mtd,
const u_char *buf, int len)
{
if (len <= mtd->oobsize)
omap_write_buf_pref(mtd, buf, len);
else
/* start transfer in DMA mode */
omap_nand_dma_transfer(mtd, (u_char *) buf, len, 0x1);
}
/*
* omap_nand_irq - GMPC irq handler
* @this_irq: gpmc irq number
* @dev: omap_nand_info structure pointer is passed here
*/
static irqreturn_t omap_nand_irq(int this_irq, void *dev)
{
struct omap_nand_info *info = (struct omap_nand_info *) dev;
u32 bytes;
u32 irq_stat;
irq_stat = gpmc_read_status(GPMC_GET_IRQ_STATUS);
bytes = gpmc_read_status(GPMC_PREFETCH_FIFO_CNT);
bytes = bytes & 0xFFFC; /* io in multiple of 4 bytes */
if (info->iomode == OMAP_NAND_IO_WRITE) { /* checks for write io */
if (irq_stat & 0x2)
goto done;
if (info->buf_len && (info->buf_len < bytes))
bytes = info->buf_len;
else if (!info->buf_len)
bytes = 0;
iowrite32_rep(info->nand.IO_ADDR_W,
(u32 *)info->buf, bytes >> 2);
info->buf = info->buf + bytes;
info->buf_len -= bytes;
} else {
ioread32_rep(info->nand.IO_ADDR_R,
(u32 *)info->buf, bytes >> 2);
info->buf = info->buf + bytes;
if (irq_stat & 0x2)
goto done;
}
gpmc_cs_configure(info->gpmc_cs, GPMC_SET_IRQ_STATUS, irq_stat);
return IRQ_HANDLED;
done:
complete(&info->comp);
/* disable irq */
gpmc_cs_configure(info->gpmc_cs, GPMC_ENABLE_IRQ, 0);
/* clear status */
gpmc_cs_configure(info->gpmc_cs, GPMC_SET_IRQ_STATUS, irq_stat);
return IRQ_HANDLED;
}
/*
* omap_read_buf_irq_pref - read data from NAND controller into buffer
* @mtd: MTD device structure
* @buf: buffer to store date
* @len: number of bytes to read
*/
static void omap_read_buf_irq_pref(struct mtd_info *mtd, u_char *buf, int len)
{
struct omap_nand_info *info = container_of(mtd,
struct omap_nand_info, mtd);
int ret = 0;
if (len <= mtd->oobsize) {
omap_read_buf_pref(mtd, buf, len);
return;
}
info->iomode = OMAP_NAND_IO_READ;
info->buf = buf;
init_completion(&info->comp);
/* configure and start prefetch transfer */
ret = gpmc_prefetch_enable(info->gpmc_cs,
PREFETCH_FIFOTHRESHOLD_MAX/2, 0x0, len, 0x0);
if (ret)
/* PFPW engine is busy, use cpu copy method */
goto out_copy;
info->buf_len = len;
/* enable irq */
gpmc_cs_configure(info->gpmc_cs, GPMC_ENABLE_IRQ,
(GPMC_IRQ_FIFOEVENTENABLE | GPMC_IRQ_COUNT_EVENT));
/* waiting for read to complete */
wait_for_completion(&info->comp);
/* disable and stop the PFPW engine */
gpmc_prefetch_reset(info->gpmc_cs);
return;
out_copy:
if (info->nand.options & NAND_BUSWIDTH_16)
omap_read_buf16(mtd, buf, len);
else
omap_read_buf8(mtd, buf, len);
}
/*
* omap_write_buf_irq_pref - write buffer to NAND controller
* @mtd: MTD device structure
* @buf: data buffer
* @len: number of bytes to write
*/
static void omap_write_buf_irq_pref(struct mtd_info *mtd,
const u_char *buf, int len)
{
struct omap_nand_info *info = container_of(mtd,
struct omap_nand_info, mtd);
int ret = 0;
unsigned long tim, limit;
if (len <= mtd->oobsize) {
omap_write_buf_pref(mtd, buf, len);
return;
}
info->iomode = OMAP_NAND_IO_WRITE;
info->buf = (u_char *) buf;
init_completion(&info->comp);
/* configure and start prefetch transfer : size=24 */
ret = gpmc_prefetch_enable(info->gpmc_cs,
(PREFETCH_FIFOTHRESHOLD_MAX * 3) / 8, 0x0, len, 0x1);
if (ret)
/* PFPW engine is busy, use cpu copy method */
goto out_copy;
info->buf_len = len;
/* enable irq */
gpmc_cs_configure(info->gpmc_cs, GPMC_ENABLE_IRQ,
(GPMC_IRQ_FIFOEVENTENABLE | GPMC_IRQ_COUNT_EVENT));
/* waiting for write to complete */
wait_for_completion(&info->comp);
/* wait for data to flushed-out before reset the prefetch */
tim = 0;
limit = (loops_per_jiffy * msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
while (gpmc_read_status(GPMC_PREFETCH_COUNT) && (tim++ < limit))
cpu_relax();
/* disable and stop the PFPW engine */
gpmc_prefetch_reset(info->gpmc_cs);
return;
out_copy:
if (info->nand.options & NAND_BUSWIDTH_16)
omap_write_buf16(mtd, buf, len);
else
omap_write_buf8(mtd, buf, len);
}
/**
* omap_verify_buf - Verify chip data against buffer
* @mtd: MTD device structure
* @buf: buffer containing the data to compare
* @len: number of bytes to compare
*/
static int omap_verify_buf(struct mtd_info *mtd, const u_char * buf, int len)
{
struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
mtd);
u16 *p = (u16 *) buf;
len >>= 1;
while (len--) {
if (*p++ != cpu_to_le16(readw(info->nand.IO_ADDR_R)))
return -EFAULT;
}
return 0;
}
/**
* gen_true_ecc - This function will generate true ECC value
* @ecc_buf: buffer to store ecc code
*
* This generated true ECC value can be used when correcting
* data read from NAND flash memory core
*/
static void gen_true_ecc(u8 *ecc_buf)
{
u32 tmp = ecc_buf[0] | (ecc_buf[1] << 16) |
((ecc_buf[2] & 0xF0) << 20) | ((ecc_buf[2] & 0x0F) << 8);
ecc_buf[0] = ~(P64o(tmp) | P64e(tmp) | P32o(tmp) | P32e(tmp) |
P16o(tmp) | P16e(tmp) | P8o(tmp) | P8e(tmp));
ecc_buf[1] = ~(P1024o(tmp) | P1024e(tmp) | P512o(tmp) | P512e(tmp) |
P256o(tmp) | P256e(tmp) | P128o(tmp) | P128e(tmp));
ecc_buf[2] = ~(P4o(tmp) | P4e(tmp) | P2o(tmp) | P2e(tmp) | P1o(tmp) |
P1e(tmp) | P2048o(tmp) | P2048e(tmp));
}
/**
* omap_compare_ecc - Detect (2 bits) and correct (1 bit) error in data
* @ecc_data1: ecc code from nand spare area
* @ecc_data2: ecc code from hardware register obtained from hardware ecc
* @page_data: page data
*
* This function compares two ECC's and indicates if there is an error.
* If the error can be corrected it will be corrected to the buffer.
* If there is no error, %0 is returned. If there is an error but it
* was corrected, %1 is returned. Otherwise, %-1 is returned.
*/
static int omap_compare_ecc(u8 *ecc_data1, /* read from NAND memory */
u8 *ecc_data2, /* read from register */
u8 *page_data)
{
uint i;
u8 tmp0_bit[8], tmp1_bit[8], tmp2_bit[8];
u8 comp0_bit[8], comp1_bit[8], comp2_bit[8];
u8 ecc_bit[24];
u8 ecc_sum = 0;
u8 find_bit = 0;
uint find_byte = 0;
int isEccFF;
isEccFF = ((*(u32 *)ecc_data1 & 0xFFFFFF) == 0xFFFFFF);
gen_true_ecc(ecc_data1);
gen_true_ecc(ecc_data2);
for (i = 0; i <= 2; i++) {
*(ecc_data1 + i) = ~(*(ecc_data1 + i));
*(ecc_data2 + i) = ~(*(ecc_data2 + i));
}
for (i = 0; i < 8; i++) {
tmp0_bit[i] = *ecc_data1 % 2;
*ecc_data1 = *ecc_data1 / 2;
}
for (i = 0; i < 8; i++) {
tmp1_bit[i] = *(ecc_data1 + 1) % 2;
*(ecc_data1 + 1) = *(ecc_data1 + 1) / 2;
}
for (i = 0; i < 8; i++) {
tmp2_bit[i] = *(ecc_data1 + 2) % 2;
*(ecc_data1 + 2) = *(ecc_data1 + 2) / 2;
}
for (i = 0; i < 8; i++) {
comp0_bit[i] = *ecc_data2 % 2;
*ecc_data2 = *ecc_data2 / 2;
}
for (i = 0; i < 8; i++) {
comp1_bit[i] = *(ecc_data2 + 1) % 2;
*(ecc_data2 + 1) = *(ecc_data2 + 1) / 2;
}
for (i = 0; i < 8; i++) {
comp2_bit[i] = *(ecc_data2 + 2) % 2;
*(ecc_data2 + 2) = *(ecc_data2 + 2) / 2;
}
for (i = 0; i < 6; i++)
ecc_bit[i] = tmp2_bit[i + 2] ^ comp2_bit[i + 2];
for (i = 0; i < 8; i++)
ecc_bit[i + 6] = tmp0_bit[i] ^ comp0_bit[i];
for (i = 0; i < 8; i++)
ecc_bit[i + 14] = tmp1_bit[i] ^ comp1_bit[i];
ecc_bit[22] = tmp2_bit[0] ^ comp2_bit[0];
ecc_bit[23] = tmp2_bit[1] ^ comp2_bit[1];
for (i = 0; i < 24; i++)
ecc_sum += ecc_bit[i];
switch (ecc_sum) {
case 0:
/* Not reached because this function is not called if
* ECC values are equal
*/
return 0;
case 1:
/* Uncorrectable error */
DEBUG(MTD_DEBUG_LEVEL0, "ECC UNCORRECTED_ERROR 1\n");
return -1;
case 11:
/* UN-Correctable error */
DEBUG(MTD_DEBUG_LEVEL0, "ECC UNCORRECTED_ERROR B\n");
return -1;
case 12:
/* Correctable error */
find_byte = (ecc_bit[23] << 8) +
(ecc_bit[21] << 7) +
(ecc_bit[19] << 6) +
(ecc_bit[17] << 5) +
(ecc_bit[15] << 4) +
(ecc_bit[13] << 3) +
(ecc_bit[11] << 2) +
(ecc_bit[9] << 1) +
ecc_bit[7];
find_bit = (ecc_bit[5] << 2) + (ecc_bit[3] << 1) + ecc_bit[1];
DEBUG(MTD_DEBUG_LEVEL0, "Correcting single bit ECC error at "
"offset: %d, bit: %d\n", find_byte, find_bit);
page_data[find_byte] ^= (1 << find_bit);
return 1;
default:
if (isEccFF) {
if (ecc_data2[0] == 0 &&
ecc_data2[1] == 0 &&
ecc_data2[2] == 0)
return 0;
}
DEBUG(MTD_DEBUG_LEVEL0, "UNCORRECTED_ERROR default\n");
return -1;
}
}
/**
* omap_correct_data - Compares the ECC read with HW generated ECC
* @mtd: MTD device structure
* @dat: page data
* @read_ecc: ecc read from nand flash
* @calc_ecc: ecc read from HW ECC registers
*
* Compares the ecc read from nand spare area with ECC registers values
* and if ECC's mismatched, it will call 'omap_compare_ecc' for error
* detection and correction. If there are no errors, %0 is returned. If
* there were errors and all of the errors were corrected, the number of
* corrected errors is returned. If uncorrectable errors exist, %-1 is
* returned.
*/
static int omap_correct_data(struct mtd_info *mtd, u_char *dat,
u_char *read_ecc, u_char *calc_ecc)
{
struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
mtd);
int blockCnt = 0, i = 0, ret = 0;
int stat = 0;
/* Ex NAND_ECC_HW12_2048 */
if ((info->nand.ecc.mode == NAND_ECC_HW) &&
(info->nand.ecc.size == 2048))
blockCnt = 4;
else
blockCnt = 1;
for (i = 0; i < blockCnt; i++) {
if (memcmp(read_ecc, calc_ecc, 3) != 0) {
ret = omap_compare_ecc(read_ecc, calc_ecc, dat);
if (ret < 0)
return ret;
/* keep track of the number of corrected errors */
stat += ret;
}
read_ecc += 3;
calc_ecc += 3;
dat += 512;
}
return stat;
}
/**
* omap_calcuate_ecc - Generate non-inverted ECC bytes.
* @mtd: MTD device structure
* @dat: The pointer to data on which ecc is computed
* @ecc_code: The ecc_code buffer
*
* Using noninverted ECC can be considered ugly since writing a blank
* page ie. padding will clear the ECC bytes. This is no problem as long
* nobody is trying to write data on the seemingly unused page. Reading
* an erased page will produce an ECC mismatch between generated and read
* ECC bytes that has to be dealt with separately.
*/
static int omap_calculate_ecc(struct mtd_info *mtd, const u_char *dat,
u_char *ecc_code)
{
struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
mtd);
return gpmc_calculate_ecc(info->gpmc_cs, dat, ecc_code);
}
/**
* omap_enable_hwecc - This function enables the hardware ecc functionality
* @mtd: MTD device structure
* @mode: Read/Write mode
*/
static void omap_enable_hwecc(struct mtd_info *mtd, int mode)
{
struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
mtd);
struct nand_chip *chip = mtd->priv;
unsigned int dev_width = (chip->options & NAND_BUSWIDTH_16) ? 1 : 0;
gpmc_enable_hwecc(info->gpmc_cs, mode, dev_width, info->nand.ecc.size);
}
/**
* omap_wait - wait until the command is done
* @mtd: MTD device structure
* @chip: NAND Chip structure
*
* Wait function is called during Program and erase operations and
* the way it is called from MTD layer, we should wait till the NAND
* chip is ready after the programming/erase operation has completed.
*
* Erase can take up to 400ms and program up to 20ms according to
* general NAND and SmartMedia specs
*/
static int omap_wait(struct mtd_info *mtd, struct nand_chip *chip)
{
struct nand_chip *this = mtd->priv;
struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
mtd);
unsigned long timeo = jiffies;
int status = NAND_STATUS_FAIL, state = this->state;
if (state == FL_ERASING)
timeo += (HZ * 400) / 1000;
else
timeo += (HZ * 20) / 1000;
gpmc_nand_write(info->gpmc_cs,
GPMC_NAND_COMMAND, (NAND_CMD_STATUS & 0xFF));
while (time_before(jiffies, timeo)) {
status = gpmc_nand_read(info->gpmc_cs, GPMC_NAND_DATA);
if (status & NAND_STATUS_READY)
break;
cond_resched();
}
return status;
}
/**
* omap_dev_ready - calls the platform specific dev_ready function
* @mtd: MTD device structure
*/
static int omap_dev_ready(struct mtd_info *mtd)
{
unsigned int val = 0;
struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
mtd);
val = gpmc_read_status(GPMC_GET_IRQ_STATUS);
if ((val & 0x100) == 0x100) {
/* Clear IRQ Interrupt */
val |= 0x100;
val &= ~(0x0);
gpmc_cs_configure(info->gpmc_cs, GPMC_SET_IRQ_STATUS, val);
} else {
unsigned int cnt = 0;
while (cnt++ < 0x1FF) {
if ((val & 0x100) == 0x100)
return 0;
val = gpmc_read_status(GPMC_GET_IRQ_STATUS);
}
}
return 1;
}
static int __devinit omap_nand_probe(struct platform_device *pdev)
{
struct omap_nand_info *info;
struct omap_nand_platform_data *pdata;
int err;
int i, offset;
pdata = pdev->dev.platform_data;
if (pdata == NULL) {
dev_err(&pdev->dev, "platform data missing\n");
return -ENODEV;
}
info = kzalloc(sizeof(struct omap_nand_info), GFP_KERNEL);
if (!info)
return -ENOMEM;
platform_set_drvdata(pdev, info);
spin_lock_init(&info->controller.lock);
init_waitqueue_head(&info->controller.wq);
info->pdev = pdev;
info->gpmc_cs = pdata->cs;
info->phys_base = pdata->phys_base;
info->mtd.priv = &info->nand;
info->mtd.name = dev_name(&pdev->dev);
info->mtd.owner = THIS_MODULE;
info->nand.options = pdata->devsize;
info->nand.options |= NAND_SKIP_BBTSCAN;
/* NAND write protect off */
gpmc_cs_configure(info->gpmc_cs, GPMC_CONFIG_WP, 0);
if (!request_mem_region(info->phys_base, NAND_IO_SIZE,
pdev->dev.driver->name)) {
err = -EBUSY;
goto out_free_info;
}
info->nand.IO_ADDR_R = ioremap(info->phys_base, NAND_IO_SIZE);
if (!info->nand.IO_ADDR_R) {
err = -ENOMEM;
goto out_release_mem_region;
}
info->nand.controller = &info->controller;
info->nand.IO_ADDR_W = info->nand.IO_ADDR_R;
info->nand.cmd_ctrl = omap_hwcontrol;
/*
* If RDY/BSY line is connected to OMAP then use the omap ready
* funcrtion and the generic nand_wait function which reads the status
* register after monitoring the RDY/BSY line.Otherwise use a standard
* chip delay which is slightly more than tR (AC Timing) of the NAND
* device and read status register until you get a failure or success
*/
if (pdata->dev_ready) {
info->nand.dev_ready = omap_dev_ready;
info->nand.chip_delay = 0;
} else {
info->nand.waitfunc = omap_wait;
info->nand.chip_delay = 50;
}
switch (pdata->xfer_type) {
case NAND_OMAP_PREFETCH_POLLED:
info->nand.read_buf = omap_read_buf_pref;
info->nand.write_buf = omap_write_buf_pref;
break;
case NAND_OMAP_POLLED:
if (info->nand.options & NAND_BUSWIDTH_16) {
info->nand.read_buf = omap_read_buf16;
info->nand.write_buf = omap_write_buf16;
} else {
info->nand.read_buf = omap_read_buf8;
info->nand.write_buf = omap_write_buf8;
}
break;
case NAND_OMAP_PREFETCH_DMA:
err = omap_request_dma(OMAP24XX_DMA_GPMC, "NAND",
omap_nand_dma_cb, &info->comp, &info->dma_ch);
if (err < 0) {
info->dma_ch = -1;
dev_err(&pdev->dev, "DMA request failed!\n");
goto out_release_mem_region;
} else {
omap_set_dma_dest_burst_mode(info->dma_ch,
OMAP_DMA_DATA_BURST_16);
omap_set_dma_src_burst_mode(info->dma_ch,
OMAP_DMA_DATA_BURST_16);
info->nand.read_buf = omap_read_buf_dma_pref;
info->nand.write_buf = omap_write_buf_dma_pref;
}
break;
case NAND_OMAP_PREFETCH_IRQ:
err = request_irq(pdata->gpmc_irq,
omap_nand_irq, IRQF_SHARED, "gpmc-nand", info);
if (err) {
dev_err(&pdev->dev, "requesting irq(%d) error:%d",
pdata->gpmc_irq, err);
goto out_release_mem_region;
} else {
info->gpmc_irq = pdata->gpmc_irq;
info->nand.read_buf = omap_read_buf_irq_pref;
info->nand.write_buf = omap_write_buf_irq_pref;
}
break;
default:
dev_err(&pdev->dev,
"xfer_type(%d) not supported!\n", pdata->xfer_type);
err = -EINVAL;
goto out_release_mem_region;
}
info->nand.verify_buf = omap_verify_buf;
/* selsect the ecc type */
if (pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_DEFAULT)
info->nand.ecc.mode = NAND_ECC_SOFT;
else if ((pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW) ||
(pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW_ROMCODE)) {
info->nand.ecc.bytes = 3;
info->nand.ecc.size = 512;
info->nand.ecc.calculate = omap_calculate_ecc;
info->nand.ecc.hwctl = omap_enable_hwecc;
info->nand.ecc.correct = omap_correct_data;
info->nand.ecc.mode = NAND_ECC_HW;
}
/* DIP switches on some boards change between 8 and 16 bit
* bus widths for flash. Try the other width if the first try fails.
*/
if (nand_scan_ident(&info->mtd, 1, NULL)) {
info->nand.options ^= NAND_BUSWIDTH_16;
if (nand_scan_ident(&info->mtd, 1, NULL)) {
err = -ENXIO;
goto out_release_mem_region;
}
}
/* rom code layout */
if (pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW_ROMCODE) {
if (info->nand.options & NAND_BUSWIDTH_16)
offset = 2;
else {
offset = 1;
info->nand.badblock_pattern = &bb_descrip_flashbased;
}
omap_oobinfo.eccbytes = 3 * (info->mtd.oobsize/16);
for (i = 0; i < omap_oobinfo.eccbytes; i++)
omap_oobinfo.eccpos[i] = i+offset;
omap_oobinfo.oobfree->offset = offset + omap_oobinfo.eccbytes;
omap_oobinfo.oobfree->length = info->mtd.oobsize -
(offset + omap_oobinfo.eccbytes);
info->nand.ecc.layout = &omap_oobinfo;
}
/* second phase scan */
if (nand_scan_tail(&info->mtd)) {
err = -ENXIO;
goto out_release_mem_region;
}
err = parse_mtd_partitions(&info->mtd, part_probes, &info->parts, 0);
if (err > 0)
mtd_device_register(&info->mtd, info->parts, err);
else if (pdata->parts)
mtd_device_register(&info->mtd, pdata->parts, pdata->nr_parts);
else
mtd_device_register(&info->mtd, NULL, 0);
platform_set_drvdata(pdev, &info->mtd);
return 0;
out_release_mem_region:
release_mem_region(info->phys_base, NAND_IO_SIZE);
out_free_info:
kfree(info);
return err;
}
static int omap_nand_remove(struct platform_device *pdev)
{
struct mtd_info *mtd = platform_get_drvdata(pdev);
struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
mtd);
platform_set_drvdata(pdev, NULL);
if (info->dma_ch != -1)
omap_free_dma(info->dma_ch);
if (info->gpmc_irq)
free_irq(info->gpmc_irq, info);
/* Release NAND device, its internal structures and partitions */
nand_release(&info->mtd);
iounmap(info->nand.IO_ADDR_R);
release_mem_region(info->phys_base, NAND_IO_SIZE);
kfree(info);
return 0;
}
static struct platform_driver omap_nand_driver = {
.probe = omap_nand_probe,
.remove = omap_nand_remove,
.driver = {
.name = DRIVER_NAME,
.owner = THIS_MODULE,
},
};
static int __init omap_nand_init(void)
{
pr_info("%s driver initializing\n", DRIVER_NAME);
return platform_driver_register(&omap_nand_driver);
}
static void __exit omap_nand_exit(void)
{
platform_driver_unregister(&omap_nand_driver);
}
module_init(omap_nand_init);
module_exit(omap_nand_exit);
MODULE_ALIAS("platform:" DRIVER_NAME);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Glue layer for NAND flash on TI OMAP boards");