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atmel_nand.c
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/*
* Copyright © 2003 Rick Bronson
*
* Derived from drivers/mtd/nand/autcpu12.c
* Copyright © 2001 Thomas Gleixner (gleixner@autronix.de)
*
* Derived from drivers/mtd/spia.c
* Copyright © 2000 Steven J. Hill (sjhill@cotw.com)
*
*
* Add Hardware ECC support for AT91SAM9260 / AT91SAM9263
* Richard Genoud (richard.genoud@gmail.com), Adeneo Copyright © 2007
*
* Derived from Das U-Boot source code
* (u-boot-1.1.5/board/atmel/at91sam9263ek/nand.c)
* © Copyright 2006 ATMEL Rousset, Lacressonniere Nicolas
*
* Add Programmable Multibit ECC support for various AT91 SoC
* © Copyright 2012 ATMEL, Hong Xu
*
* Add Nand Flash Controller support for SAMA5 SoC
* © Copyright 2013 ATMEL, Josh Wu (josh.wu@atmel.com)
*
* 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/dma-mapping.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_gpio.h>
#include <linux/of_mtd.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <linux/delay.h>
#include <linux/dmaengine.h>
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/platform_data/atmel.h>
static int use_dma = 1;
module_param(use_dma, int, 0);
static int on_flash_bbt = 0;
module_param(on_flash_bbt, int, 0);
/* Register access macros */
#define ecc_readl(add, reg) \
__raw_readl(add + ATMEL_ECC_##reg)
#define ecc_writel(add, reg, value) \
__raw_writel((value), add + ATMEL_ECC_##reg)
#include "atmel_nand_ecc.h" /* Hardware ECC registers */
#include "atmel_nand_nfc.h" /* Nand Flash Controller definition */
/* oob layout for large page size
* bad block info is on bytes 0 and 1
* the bytes have to be consecutives to avoid
* several NAND_CMD_RNDOUT during read
*/
static struct nand_ecclayout atmel_oobinfo_large = {
.eccbytes = 4,
.eccpos = {60, 61, 62, 63},
.oobfree = {
{2, 58}
},
};
/* oob layout for small page size
* bad block info is on bytes 4 and 5
* the bytes have to be consecutives to avoid
* several NAND_CMD_RNDOUT during read
*/
static struct nand_ecclayout atmel_oobinfo_small = {
.eccbytes = 4,
.eccpos = {0, 1, 2, 3},
.oobfree = {
{6, 10}
},
};
struct atmel_nfc {
void __iomem *base_cmd_regs;
void __iomem *hsmc_regs;
void __iomem *sram_bank0;
dma_addr_t sram_bank0_phys;
bool use_nfc_sram;
bool write_by_sram;
bool is_initialized;
struct completion comp_ready;
struct completion comp_cmd_done;
struct completion comp_xfer_done;
/* Point to the sram bank which include readed data via NFC */
void __iomem *data_in_sram;
bool will_write_sram;
};
static struct atmel_nfc nand_nfc;
struct atmel_nand_host {
struct nand_chip nand_chip;
struct mtd_info mtd;
void __iomem *io_base;
dma_addr_t io_phys;
struct atmel_nand_data board;
struct device *dev;
void __iomem *ecc;
struct completion comp;
struct dma_chan *dma_chan;
struct atmel_nfc *nfc;
bool has_pmecc;
u8 pmecc_corr_cap;
u16 pmecc_sector_size;
u32 pmecc_lookup_table_offset;
u32 pmecc_lookup_table_offset_512;
u32 pmecc_lookup_table_offset_1024;
int pmecc_bytes_per_sector;
int pmecc_sector_number;
int pmecc_degree; /* Degree of remainders */
int pmecc_cw_len; /* Length of codeword */
void __iomem *pmerrloc_base;
void __iomem *pmecc_rom_base;
/* lookup table for alpha_to and index_of */
void __iomem *pmecc_alpha_to;
void __iomem *pmecc_index_of;
/* data for pmecc computation */
int16_t *pmecc_partial_syn;
int16_t *pmecc_si;
int16_t *pmecc_smu; /* Sigma table */
int16_t *pmecc_lmu; /* polynomal order */
int *pmecc_mu;
int *pmecc_dmu;
int *pmecc_delta;
};
static struct nand_ecclayout atmel_pmecc_oobinfo;
/*
* Enable NAND.
*/
static void atmel_nand_enable(struct atmel_nand_host *host)
{
if (gpio_is_valid(host->board.enable_pin))
gpio_set_value(host->board.enable_pin, 0);
}
/*
* Disable NAND.
*/
static void atmel_nand_disable(struct atmel_nand_host *host)
{
if (gpio_is_valid(host->board.enable_pin))
gpio_set_value(host->board.enable_pin, 1);
}
/*
* Hardware specific access to control-lines
*/
static void atmel_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
{
struct nand_chip *nand_chip = mtd->priv;
struct atmel_nand_host *host = nand_chip->priv;
if (ctrl & NAND_CTRL_CHANGE) {
if (ctrl & NAND_NCE)
atmel_nand_enable(host);
else
atmel_nand_disable(host);
}
if (cmd == NAND_CMD_NONE)
return;
if (ctrl & NAND_CLE)
writeb(cmd, host->io_base + (1 << host->board.cle));
else
writeb(cmd, host->io_base + (1 << host->board.ale));
}
/*
* Read the Device Ready pin.
*/
static int atmel_nand_device_ready(struct mtd_info *mtd)
{
struct nand_chip *nand_chip = mtd->priv;
struct atmel_nand_host *host = nand_chip->priv;
return gpio_get_value(host->board.rdy_pin) ^
!!host->board.rdy_pin_active_low;
}
/* Set up for hardware ready pin and enable pin. */
static int atmel_nand_set_enable_ready_pins(struct mtd_info *mtd)
{
struct nand_chip *chip = mtd->priv;
struct atmel_nand_host *host = chip->priv;
int res = 0;
if (gpio_is_valid(host->board.rdy_pin)) {
res = devm_gpio_request(host->dev,
host->board.rdy_pin, "nand_rdy");
if (res < 0) {
dev_err(host->dev,
"can't request rdy gpio %d\n",
host->board.rdy_pin);
return res;
}
res = gpio_direction_input(host->board.rdy_pin);
if (res < 0) {
dev_err(host->dev,
"can't request input direction rdy gpio %d\n",
host->board.rdy_pin);
return res;
}
chip->dev_ready = atmel_nand_device_ready;
}
if (gpio_is_valid(host->board.enable_pin)) {
res = devm_gpio_request(host->dev,
host->board.enable_pin, "nand_enable");
if (res < 0) {
dev_err(host->dev,
"can't request enable gpio %d\n",
host->board.enable_pin);
return res;
}
res = gpio_direction_output(host->board.enable_pin, 1);
if (res < 0) {
dev_err(host->dev,
"can't request output direction enable gpio %d\n",
host->board.enable_pin);
return res;
}
}
return res;
}
static void memcpy32_fromio(void *trg, const void __iomem *src, size_t size)
{
int i;
u32 *t = trg;
const __iomem u32 *s = src;
for (i = 0; i < (size >> 2); i++)
*t++ = readl_relaxed(s++);
}
static void memcpy32_toio(void __iomem *trg, const void *src, int size)
{
int i;
u32 __iomem *t = trg;
const u32 *s = src;
for (i = 0; i < (size >> 2); i++)
writel_relaxed(*s++, t++);
}
/*
* Minimal-overhead PIO for data access.
*/
static void atmel_read_buf8(struct mtd_info *mtd, u8 *buf, int len)
{
struct nand_chip *nand_chip = mtd->priv;
struct atmel_nand_host *host = nand_chip->priv;
if (host->nfc && host->nfc->use_nfc_sram && host->nfc->data_in_sram) {
memcpy32_fromio(buf, host->nfc->data_in_sram, len);
host->nfc->data_in_sram += len;
} else {
__raw_readsb(nand_chip->IO_ADDR_R, buf, len);
}
}
static void atmel_read_buf16(struct mtd_info *mtd, u8 *buf, int len)
{
struct nand_chip *nand_chip = mtd->priv;
struct atmel_nand_host *host = nand_chip->priv;
if (host->nfc && host->nfc->use_nfc_sram && host->nfc->data_in_sram) {
memcpy32_fromio(buf, host->nfc->data_in_sram, len);
host->nfc->data_in_sram += len;
} else {
__raw_readsw(nand_chip->IO_ADDR_R, buf, len / 2);
}
}
static void atmel_write_buf8(struct mtd_info *mtd, const u8 *buf, int len)
{
struct nand_chip *nand_chip = mtd->priv;
__raw_writesb(nand_chip->IO_ADDR_W, buf, len);
}
static void atmel_write_buf16(struct mtd_info *mtd, const u8 *buf, int len)
{
struct nand_chip *nand_chip = mtd->priv;
__raw_writesw(nand_chip->IO_ADDR_W, buf, len / 2);
}
static void dma_complete_func(void *completion)
{
complete(completion);
}
static int nfc_set_sram_bank(struct atmel_nand_host *host, unsigned int bank)
{
/* NFC only has two banks. Must be 0 or 1 */
if (bank > 1)
return -EINVAL;
if (bank) {
/* Only for a 2k-page or lower flash, NFC can handle 2 banks */
if (host->mtd.writesize > 2048)
return -EINVAL;
nfc_writel(host->nfc->hsmc_regs, BANK, ATMEL_HSMC_NFC_BANK1);
} else {
nfc_writel(host->nfc->hsmc_regs, BANK, ATMEL_HSMC_NFC_BANK0);
}
return 0;
}
static uint nfc_get_sram_off(struct atmel_nand_host *host)
{
if (nfc_readl(host->nfc->hsmc_regs, BANK) & ATMEL_HSMC_NFC_BANK1)
return NFC_SRAM_BANK1_OFFSET;
else
return 0;
}
static dma_addr_t nfc_sram_phys(struct atmel_nand_host *host)
{
if (nfc_readl(host->nfc->hsmc_regs, BANK) & ATMEL_HSMC_NFC_BANK1)
return host->nfc->sram_bank0_phys + NFC_SRAM_BANK1_OFFSET;
else
return host->nfc->sram_bank0_phys;
}
static int atmel_nand_dma_op(struct mtd_info *mtd, void *buf, int len,
int is_read)
{
struct dma_device *dma_dev;
enum dma_ctrl_flags flags;
dma_addr_t dma_src_addr, dma_dst_addr, phys_addr;
struct dma_async_tx_descriptor *tx = NULL;
dma_cookie_t cookie;
struct nand_chip *chip = mtd->priv;
struct atmel_nand_host *host = chip->priv;
void *p = buf;
int err = -EIO;
enum dma_data_direction dir = is_read ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
struct atmel_nfc *nfc = host->nfc;
if (buf >= high_memory)
goto err_buf;
dma_dev = host->dma_chan->device;
flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
phys_addr = dma_map_single(dma_dev->dev, p, len, dir);
if (dma_mapping_error(dma_dev->dev, phys_addr)) {
dev_err(host->dev, "Failed to dma_map_single\n");
goto err_buf;
}
if (is_read) {
if (nfc && nfc->data_in_sram)
dma_src_addr = nfc_sram_phys(host) + (nfc->data_in_sram
- (nfc->sram_bank0 + nfc_get_sram_off(host)));
else
dma_src_addr = host->io_phys;
dma_dst_addr = phys_addr;
} else {
dma_src_addr = phys_addr;
if (nfc && nfc->write_by_sram)
dma_dst_addr = nfc_sram_phys(host);
else
dma_dst_addr = host->io_phys;
}
tx = dma_dev->device_prep_dma_memcpy(host->dma_chan, dma_dst_addr,
dma_src_addr, len, flags);
if (!tx) {
dev_err(host->dev, "Failed to prepare DMA memcpy\n");
goto err_dma;
}
init_completion(&host->comp);
tx->callback = dma_complete_func;
tx->callback_param = &host->comp;
cookie = tx->tx_submit(tx);
if (dma_submit_error(cookie)) {
dev_err(host->dev, "Failed to do DMA tx_submit\n");
goto err_dma;
}
dma_async_issue_pending(host->dma_chan);
wait_for_completion(&host->comp);
if (is_read && nfc && nfc->data_in_sram)
/* After read data from SRAM, need to increase the position */
nfc->data_in_sram += len;
err = 0;
err_dma:
dma_unmap_single(dma_dev->dev, phys_addr, len, dir);
err_buf:
if (err != 0)
dev_dbg(host->dev, "Fall back to CPU I/O\n");
return err;
}
static void atmel_read_buf(struct mtd_info *mtd, u8 *buf, int len)
{
struct nand_chip *chip = mtd->priv;
struct atmel_nand_host *host = chip->priv;
if (use_dma && len > mtd->oobsize)
/* only use DMA for bigger than oob size: better performances */
if (atmel_nand_dma_op(mtd, buf, len, 1) == 0)
return;
if (host->board.bus_width_16)
atmel_read_buf16(mtd, buf, len);
else
atmel_read_buf8(mtd, buf, len);
}
static void atmel_write_buf(struct mtd_info *mtd, const u8 *buf, int len)
{
struct nand_chip *chip = mtd->priv;
struct atmel_nand_host *host = chip->priv;
if (use_dma && len > mtd->oobsize)
/* only use DMA for bigger than oob size: better performances */
if (atmel_nand_dma_op(mtd, (void *)buf, len, 0) == 0)
return;
if (host->board.bus_width_16)
atmel_write_buf16(mtd, buf, len);
else
atmel_write_buf8(mtd, buf, len);
}
/*
* Return number of ecc bytes per sector according to sector size and
* correction capability
*
* Following table shows what at91 PMECC supported:
* Correction Capability Sector_512_bytes Sector_1024_bytes
* ===================== ================ =================
* 2-bits 4-bytes 4-bytes
* 4-bits 7-bytes 7-bytes
* 8-bits 13-bytes 14-bytes
* 12-bits 20-bytes 21-bytes
* 24-bits 39-bytes 42-bytes
*/
static int pmecc_get_ecc_bytes(int cap, int sector_size)
{
int m = 12 + sector_size / 512;
return (m * cap + 7) / 8;
}
static void pmecc_config_ecc_layout(struct nand_ecclayout *layout,
int oobsize, int ecc_len)
{
int i;
layout->eccbytes = ecc_len;
/* ECC will occupy the last ecc_len bytes continuously */
for (i = 0; i < ecc_len; i++)
layout->eccpos[i] = oobsize - ecc_len + i;
layout->oobfree[0].offset = 2;
layout->oobfree[0].length =
oobsize - ecc_len - layout->oobfree[0].offset;
}
static void __iomem *pmecc_get_alpha_to(struct atmel_nand_host *host)
{
int table_size;
table_size = host->pmecc_sector_size == 512 ?
PMECC_LOOKUP_TABLE_SIZE_512 : PMECC_LOOKUP_TABLE_SIZE_1024;
return host->pmecc_rom_base + host->pmecc_lookup_table_offset +
table_size * sizeof(int16_t);
}
static int pmecc_data_alloc(struct atmel_nand_host *host)
{
const int cap = host->pmecc_corr_cap;
int size;
size = (2 * cap + 1) * sizeof(int16_t);
host->pmecc_partial_syn = devm_kzalloc(host->dev, size, GFP_KERNEL);
host->pmecc_si = devm_kzalloc(host->dev, size, GFP_KERNEL);
host->pmecc_lmu = devm_kzalloc(host->dev,
(cap + 1) * sizeof(int16_t), GFP_KERNEL);
host->pmecc_smu = devm_kzalloc(host->dev,
(cap + 2) * size, GFP_KERNEL);
size = (cap + 1) * sizeof(int);
host->pmecc_mu = devm_kzalloc(host->dev, size, GFP_KERNEL);
host->pmecc_dmu = devm_kzalloc(host->dev, size, GFP_KERNEL);
host->pmecc_delta = devm_kzalloc(host->dev, size, GFP_KERNEL);
if (!host->pmecc_partial_syn ||
!host->pmecc_si ||
!host->pmecc_lmu ||
!host->pmecc_smu ||
!host->pmecc_mu ||
!host->pmecc_dmu ||
!host->pmecc_delta)
return -ENOMEM;
return 0;
}
static void pmecc_gen_syndrome(struct mtd_info *mtd, int sector)
{
struct nand_chip *nand_chip = mtd->priv;
struct atmel_nand_host *host = nand_chip->priv;
int i;
uint32_t value;
/* Fill odd syndromes */
for (i = 0; i < host->pmecc_corr_cap; i++) {
value = pmecc_readl_rem_relaxed(host->ecc, sector, i / 2);
if (i & 1)
value >>= 16;
value &= 0xffff;
host->pmecc_partial_syn[(2 * i) + 1] = (int16_t)value;
}
}
static void pmecc_substitute(struct mtd_info *mtd)
{
struct nand_chip *nand_chip = mtd->priv;
struct atmel_nand_host *host = nand_chip->priv;
int16_t __iomem *alpha_to = host->pmecc_alpha_to;
int16_t __iomem *index_of = host->pmecc_index_of;
int16_t *partial_syn = host->pmecc_partial_syn;
const int cap = host->pmecc_corr_cap;
int16_t *si;
int i, j;
/* si[] is a table that holds the current syndrome value,
* an element of that table belongs to the field
*/
si = host->pmecc_si;
memset(&si[1], 0, sizeof(int16_t) * (2 * cap - 1));
/* Computation 2t syndromes based on S(x) */
/* Odd syndromes */
for (i = 1; i < 2 * cap; i += 2) {
for (j = 0; j < host->pmecc_degree; j++) {
if (partial_syn[i] & ((unsigned short)0x1 << j))
si[i] = readw_relaxed(alpha_to + i * j) ^ si[i];
}
}
/* Even syndrome = (Odd syndrome) ** 2 */
for (i = 2, j = 1; j <= cap; i = ++j << 1) {
if (si[j] == 0) {
si[i] = 0;
} else {
int16_t tmp;
tmp = readw_relaxed(index_of + si[j]);
tmp = (tmp * 2) % host->pmecc_cw_len;
si[i] = readw_relaxed(alpha_to + tmp);
}
}
return;
}
static void pmecc_get_sigma(struct mtd_info *mtd)
{
struct nand_chip *nand_chip = mtd->priv;
struct atmel_nand_host *host = nand_chip->priv;
int16_t *lmu = host->pmecc_lmu;
int16_t *si = host->pmecc_si;
int *mu = host->pmecc_mu;
int *dmu = host->pmecc_dmu; /* Discrepancy */
int *delta = host->pmecc_delta; /* Delta order */
int cw_len = host->pmecc_cw_len;
const int16_t cap = host->pmecc_corr_cap;
const int num = 2 * cap + 1;
int16_t __iomem *index_of = host->pmecc_index_of;
int16_t __iomem *alpha_to = host->pmecc_alpha_to;
int i, j, k;
uint32_t dmu_0_count, tmp;
int16_t *smu = host->pmecc_smu;
/* index of largest delta */
int ro;
int largest;
int diff;
dmu_0_count = 0;
/* First Row */
/* Mu */
mu[0] = -1;
memset(smu, 0, sizeof(int16_t) * num);
smu[0] = 1;
/* discrepancy set to 1 */
dmu[0] = 1;
/* polynom order set to 0 */
lmu[0] = 0;
delta[0] = (mu[0] * 2 - lmu[0]) >> 1;
/* Second Row */
/* Mu */
mu[1] = 0;
/* Sigma(x) set to 1 */
memset(&smu[num], 0, sizeof(int16_t) * num);
smu[num] = 1;
/* discrepancy set to S1 */
dmu[1] = si[1];
/* polynom order set to 0 */
lmu[1] = 0;
delta[1] = (mu[1] * 2 - lmu[1]) >> 1;
/* Init the Sigma(x) last row */
memset(&smu[(cap + 1) * num], 0, sizeof(int16_t) * num);
for (i = 1; i <= cap; i++) {
mu[i + 1] = i << 1;
/* Begin Computing Sigma (Mu+1) and L(mu) */
/* check if discrepancy is set to 0 */
if (dmu[i] == 0) {
dmu_0_count++;
tmp = ((cap - (lmu[i] >> 1) - 1) / 2);
if ((cap - (lmu[i] >> 1) - 1) & 0x1)
tmp += 2;
else
tmp += 1;
if (dmu_0_count == tmp) {
for (j = 0; j <= (lmu[i] >> 1) + 1; j++)
smu[(cap + 1) * num + j] =
smu[i * num + j];
lmu[cap + 1] = lmu[i];
return;
}
/* copy polynom */
for (j = 0; j <= lmu[i] >> 1; j++)
smu[(i + 1) * num + j] = smu[i * num + j];
/* copy previous polynom order to the next */
lmu[i + 1] = lmu[i];
} else {
ro = 0;
largest = -1;
/* find largest delta with dmu != 0 */
for (j = 0; j < i; j++) {
if ((dmu[j]) && (delta[j] > largest)) {
largest = delta[j];
ro = j;
}
}
/* compute difference */
diff = (mu[i] - mu[ro]);
/* Compute degree of the new smu polynomial */
if ((lmu[i] >> 1) > ((lmu[ro] >> 1) + diff))
lmu[i + 1] = lmu[i];
else
lmu[i + 1] = ((lmu[ro] >> 1) + diff) * 2;
/* Init smu[i+1] with 0 */
for (k = 0; k < num; k++)
smu[(i + 1) * num + k] = 0;
/* Compute smu[i+1] */
for (k = 0; k <= lmu[ro] >> 1; k++) {
int16_t a, b, c;
if (!(smu[ro * num + k] && dmu[i]))
continue;
a = readw_relaxed(index_of + dmu[i]);
b = readw_relaxed(index_of + dmu[ro]);
c = readw_relaxed(index_of + smu[ro * num + k]);
tmp = a + (cw_len - b) + c;
a = readw_relaxed(alpha_to + tmp % cw_len);
smu[(i + 1) * num + (k + diff)] = a;
}
for (k = 0; k <= lmu[i] >> 1; k++)
smu[(i + 1) * num + k] ^= smu[i * num + k];
}
/* End Computing Sigma (Mu+1) and L(mu) */
/* In either case compute delta */
delta[i + 1] = (mu[i + 1] * 2 - lmu[i + 1]) >> 1;
/* Do not compute discrepancy for the last iteration */
if (i >= cap)
continue;
for (k = 0; k <= (lmu[i + 1] >> 1); k++) {
tmp = 2 * (i - 1);
if (k == 0) {
dmu[i + 1] = si[tmp + 3];
} else if (smu[(i + 1) * num + k] && si[tmp + 3 - k]) {
int16_t a, b, c;
a = readw_relaxed(index_of +
smu[(i + 1) * num + k]);
b = si[2 * (i - 1) + 3 - k];
c = readw_relaxed(index_of + b);
tmp = a + c;
tmp %= cw_len;
dmu[i + 1] = readw_relaxed(alpha_to + tmp) ^
dmu[i + 1];
}
}
}
return;
}
static int pmecc_err_location(struct mtd_info *mtd)
{
struct nand_chip *nand_chip = mtd->priv;
struct atmel_nand_host *host = nand_chip->priv;
unsigned long end_time;
const int cap = host->pmecc_corr_cap;
const int num = 2 * cap + 1;
int sector_size = host->pmecc_sector_size;
int err_nbr = 0; /* number of error */
int roots_nbr; /* number of roots */
int i;
uint32_t val;
int16_t *smu = host->pmecc_smu;
pmerrloc_writel(host->pmerrloc_base, ELDIS, PMERRLOC_DISABLE);
for (i = 0; i <= host->pmecc_lmu[cap + 1] >> 1; i++) {
pmerrloc_writel_sigma_relaxed(host->pmerrloc_base, i,
smu[(cap + 1) * num + i]);
err_nbr++;
}
val = (err_nbr - 1) << 16;
if (sector_size == 1024)
val |= 1;
pmerrloc_writel(host->pmerrloc_base, ELCFG, val);
pmerrloc_writel(host->pmerrloc_base, ELEN,
sector_size * 8 + host->pmecc_degree * cap);
end_time = jiffies + msecs_to_jiffies(PMECC_MAX_TIMEOUT_MS);
while (!(pmerrloc_readl_relaxed(host->pmerrloc_base, ELISR)
& PMERRLOC_CALC_DONE)) {
if (unlikely(time_after(jiffies, end_time))) {
dev_err(host->dev, "PMECC: Timeout to calculate error location.\n");
return -1;
}
cpu_relax();
}
roots_nbr = (pmerrloc_readl_relaxed(host->pmerrloc_base, ELISR)
& PMERRLOC_ERR_NUM_MASK) >> 8;
/* Number of roots == degree of smu hence <= cap */
if (roots_nbr == host->pmecc_lmu[cap + 1] >> 1)
return err_nbr - 1;
/* Number of roots does not match the degree of smu
* unable to correct error */
return -1;
}
static void pmecc_correct_data(struct mtd_info *mtd, uint8_t *buf, uint8_t *ecc,
int sector_num, int extra_bytes, int err_nbr)
{
struct nand_chip *nand_chip = mtd->priv;
struct atmel_nand_host *host = nand_chip->priv;
int i = 0;
int byte_pos, bit_pos, sector_size, pos;
uint32_t tmp;
uint8_t err_byte;
sector_size = host->pmecc_sector_size;
while (err_nbr) {
tmp = pmerrloc_readl_el_relaxed(host->pmerrloc_base, i) - 1;
byte_pos = tmp / 8;
bit_pos = tmp % 8;
if (byte_pos >= (sector_size + extra_bytes))
BUG(); /* should never happen */
if (byte_pos < sector_size) {
err_byte = *(buf + byte_pos);
*(buf + byte_pos) ^= (1 << bit_pos);
pos = sector_num * host->pmecc_sector_size + byte_pos;
dev_info(host->dev, "Bit flip in data area, byte_pos: %d, bit_pos: %d, 0x%02x -> 0x%02x\n",
pos, bit_pos, err_byte, *(buf + byte_pos));
} else {
/* Bit flip in OOB area */
tmp = sector_num * host->pmecc_bytes_per_sector
+ (byte_pos - sector_size);
err_byte = ecc[tmp];
ecc[tmp] ^= (1 << bit_pos);
pos = tmp + nand_chip->ecc.layout->eccpos[0];
dev_info(host->dev, "Bit flip in OOB, oob_byte_pos: %d, bit_pos: %d, 0x%02x -> 0x%02x\n",
pos, bit_pos, err_byte, ecc[tmp]);
}
i++;
err_nbr--;
}
return;
}
static int pmecc_correction(struct mtd_info *mtd, u32 pmecc_stat, uint8_t *buf,
u8 *ecc)
{
struct nand_chip *nand_chip = mtd->priv;
struct atmel_nand_host *host = nand_chip->priv;
int i, err_nbr;
uint8_t *buf_pos;
int total_err = 0;
for (i = 0; i < nand_chip->ecc.total; i++)
if (ecc[i] != 0xff)
goto normal_check;
/* Erased page, return OK */
return 0;
normal_check:
for (i = 0; i < host->pmecc_sector_number; i++) {
err_nbr = 0;
if (pmecc_stat & 0x1) {
buf_pos = buf + i * host->pmecc_sector_size;
pmecc_gen_syndrome(mtd, i);
pmecc_substitute(mtd);
pmecc_get_sigma(mtd);
err_nbr = pmecc_err_location(mtd);
if (err_nbr == -1) {
dev_err(host->dev, "PMECC: Too many errors\n");
mtd->ecc_stats.failed++;
return -EIO;
} else {
pmecc_correct_data(mtd, buf_pos, ecc, i,
host->pmecc_bytes_per_sector, err_nbr);
mtd->ecc_stats.corrected += err_nbr;
total_err += err_nbr;
}
}
pmecc_stat >>= 1;
}
return total_err;
}
static void pmecc_enable(struct atmel_nand_host *host, int ecc_op)
{
u32 val;
if (ecc_op != NAND_ECC_READ && ecc_op != NAND_ECC_WRITE) {
dev_err(host->dev, "atmel_nand: wrong pmecc operation type!");
return;
}
pmecc_writel(host->ecc, CTRL, PMECC_CTRL_RST);
pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DISABLE);
val = pmecc_readl_relaxed(host->ecc, CFG);
if (ecc_op == NAND_ECC_READ)
pmecc_writel(host->ecc, CFG, (val & ~PMECC_CFG_WRITE_OP)
| PMECC_CFG_AUTO_ENABLE);
else
pmecc_writel(host->ecc, CFG, (val | PMECC_CFG_WRITE_OP)
& ~PMECC_CFG_AUTO_ENABLE);
pmecc_writel(host->ecc, CTRL, PMECC_CTRL_ENABLE);
pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DATA);
}
static int atmel_nand_pmecc_read_page(struct mtd_info *mtd,
struct nand_chip *chip, uint8_t *buf, int oob_required, int page)
{
struct atmel_nand_host *host = chip->priv;
int eccsize = chip->ecc.size * chip->ecc.steps;
uint8_t *oob = chip->oob_poi;
uint32_t *eccpos = chip->ecc.layout->eccpos;
uint32_t stat;
unsigned long end_time;
int bitflips = 0;
if (!host->nfc || !host->nfc->use_nfc_sram)
pmecc_enable(host, NAND_ECC_READ);
chip->read_buf(mtd, buf, eccsize);
chip->read_buf(mtd, oob, mtd->oobsize);
end_time = jiffies + msecs_to_jiffies(PMECC_MAX_TIMEOUT_MS);
while ((pmecc_readl_relaxed(host->ecc, SR) & PMECC_SR_BUSY)) {
if (unlikely(time_after(jiffies, end_time))) {
dev_err(host->dev, "PMECC: Timeout to get error status.\n");
return -EIO;
}
cpu_relax();
}
stat = pmecc_readl_relaxed(host->ecc, ISR);
if (stat != 0) {
bitflips = pmecc_correction(mtd, stat, buf, &oob[eccpos[0]]);
if (bitflips < 0)
/* uncorrectable errors */
return 0;
}
return bitflips;
}
static int atmel_nand_pmecc_write_page(struct mtd_info *mtd,
struct nand_chip *chip, const uint8_t *buf, int oob_required)
{
struct atmel_nand_host *host = chip->priv;
uint32_t *eccpos = chip->ecc.layout->eccpos;
int i, j;
unsigned long end_time;
if (!host->nfc || !host->nfc->write_by_sram) {
pmecc_enable(host, NAND_ECC_WRITE);
chip->write_buf(mtd, (u8 *)buf, mtd->writesize);
}
end_time = jiffies + msecs_to_jiffies(PMECC_MAX_TIMEOUT_MS);
while ((pmecc_readl_relaxed(host->ecc, SR) & PMECC_SR_BUSY)) {
if (unlikely(time_after(jiffies, end_time))) {
dev_err(host->dev, "PMECC: Timeout to get ECC value.\n");
return -EIO;
}
cpu_relax();
}
for (i = 0; i < host->pmecc_sector_number; i++) {
for (j = 0; j < host->pmecc_bytes_per_sector; j++) {
int pos;
pos = i * host->pmecc_bytes_per_sector + j;
chip->oob_poi[eccpos[pos]] =
pmecc_readb_ecc_relaxed(host->ecc, i, j);
}
}
chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
return 0;
}