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/*
* (C) Copyright 2007-2008
* Stelian Pop <stelian@popies.net>
* Lead Tech Design <www.leadtechdesign.com>
*
* (C) Copyright 2006 ATMEL Rousset, Lacressonniere Nicolas
*
* Add Programmable Multibit ECC support for various AT91 SoC
* (C) Copyright 2012 ATMEL, Hong Xu
*
* See file CREDITS for list of people who contributed to this
* project.
*
* 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., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <asm/arch/hardware.h>
#include <asm/arch/gpio.h>
#include <asm/arch/at91_pio.h>
#include <nand.h>
#include <watchdog.h>
#ifdef CONFIG_ATMEL_NAND_HWECC
/* Register access macros */
#define ecc_readl(add, reg) \
readl(AT91_BASE_SYS + add + ATMEL_ECC_##reg)
#define ecc_writel(add, reg, value) \
writel((value), AT91_BASE_SYS + add + ATMEL_ECC_##reg)
#include "atmel_nand_ecc.h" /* Hardware ECC registers */
#ifdef CONFIG_ATMEL_NAND_HW_PMECC
struct atmel_nand_host {
struct pmecc_regs __iomem *pmecc;
struct pmecc_errloc_regs __iomem *pmerrloc;
void __iomem *pmecc_rom_base;
u8 pmecc_corr_cap;
u16 pmecc_sector_size;
u32 pmecc_index_table_offset;
int pmecc_bytes_per_sector;
int pmecc_sector_number;
int pmecc_degree; /* Degree of remainders */
int pmecc_cw_len; /* Length of codeword */
/* 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_smu[(CONFIG_PMECC_CAP + 2) * (2 * CONFIG_PMECC_CAP + 1)];
int16_t pmecc_partial_syn[2 * CONFIG_PMECC_CAP + 1];
int16_t pmecc_si[2 * CONFIG_PMECC_CAP + 1];
int16_t pmecc_lmu[CONFIG_PMECC_CAP + 1]; /* polynomal order */
int pmecc_mu[CONFIG_PMECC_CAP + 1];
int pmecc_dmu[CONFIG_PMECC_CAP + 1];
int pmecc_delta[CONFIG_PMECC_CAP + 1];
};
static struct atmel_nand_host pmecc_host;
static struct nand_ecclayout atmel_pmecc_oobinfo;
/*
* 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_INDEX_TABLE_SIZE_512 : PMECC_INDEX_TABLE_SIZE_1024;
/* the ALPHA lookup table is right behind the INDEX lookup table. */
return host->pmecc_rom_base + host->pmecc_index_table_offset +
table_size * sizeof(int16_t);
}
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 = readl(&host->pmecc->rem_port[sector].rem[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] & (0x1 << j))
si[i] = readw(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(index_of + si[j]);
tmp = (tmp * 2) % host->pmecc_cw_len;
si[i] = readw(alpha_to + tmp);
}
}
}
/*
* This function defines a Berlekamp iterative procedure for
* finding the value of the error location polynomial.
* The input is si[], initialize by pmecc_substitute().
* The output is smu[][].
*
* This function is written according to chip datasheet Chapter:
* Find the Error Location Polynomial Sigma(x) of Section:
* Programmable Multibit ECC Control (PMECC).
*/
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;
/* Init the Sigma(x) */
memset(smu, 0, sizeof(int16_t) * ARRAY_SIZE(smu));
dmu_0_count = 0;
/* First Row */
/* Mu */
mu[0] = -1;
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; */
delta[0] = -1;
/* Second Row */
/* Mu */
mu[1] = 0;
/* Sigma(x) set to 1 */
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; */
delta[1] = 0;
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(index_of + dmu[i]);
b = readw(index_of + dmu[ro]);
c = readw(index_of + smu[ro * num + k]);
tmp = a + (cw_len - b) + c;
a = readw(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(index_of +
smu[(i + 1) * num + k]);
b = si[2 * (i - 1) + 3 - k];
c = readw(index_of + b);
tmp = a + c;
tmp %= cw_len;
dmu[i + 1] = readw(alpha_to + tmp) ^
dmu[i + 1];
}
}
}
}
static int pmecc_err_location(struct mtd_info *mtd)
{
struct nand_chip *nand_chip = mtd->priv;
struct atmel_nand_host *host = nand_chip->priv;
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;
int timeout = PMECC_MAX_TIMEOUT_US;
writel(PMERRLOC_DISABLE, &host->pmerrloc->eldis);
for (i = 0; i <= host->pmecc_lmu[cap + 1] >> 1; i++) {
writel(smu[(cap + 1) * num + i], &host->pmerrloc->sigma[i]);
err_nbr++;
}
val = PMERRLOC_ELCFG_NUM_ERRORS(err_nbr - 1);
if (sector_size == 1024)
val |= PMERRLOC_ELCFG_SECTOR_1024;
writel(val, &host->pmerrloc->elcfg);
writel(sector_size * 8 + host->pmecc_degree * cap,
&host->pmerrloc->elen);
while (--timeout) {
if (readl(&host->pmerrloc->elisr) & PMERRLOC_CALC_DONE)
break;
WATCHDOG_RESET();
udelay(1);
}
if (!timeout) {
printk(KERN_ERR "atmel_nand : Timeout to calculate PMECC error location\n");
return -1;
}
roots_nbr = (readl(&host->pmerrloc->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 = readl(&host->pmerrloc->el[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;
printk(KERN_INFO "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];
printk(KERN_INFO "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, eccbytes;
uint8_t *buf_pos;
eccbytes = nand_chip->ecc.bytes;
for (i = 0; i < eccbytes; 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) {
printk(KERN_ERR "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;
}
}
pmecc_stat >>= 1;
}
return 0;
}
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;
uint8_t *oob = chip->oob_poi;
uint32_t *eccpos = chip->ecc.layout->eccpos;
uint32_t stat;
int timeout = PMECC_MAX_TIMEOUT_US;
pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_RST);
pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_DISABLE);
pmecc_writel(host->pmecc, cfg, ((pmecc_readl(host->pmecc, cfg))
& ~PMECC_CFG_WRITE_OP) | PMECC_CFG_AUTO_ENABLE);
pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_ENABLE);
pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_DATA);
chip->read_buf(mtd, buf, eccsize);
chip->read_buf(mtd, oob, mtd->oobsize);
while (--timeout) {
if (!(pmecc_readl(host->pmecc, sr) & PMECC_SR_BUSY))
break;
WATCHDOG_RESET();
udelay(1);
}
if (!timeout) {
printk(KERN_ERR "atmel_nand : Timeout to read PMECC page\n");
return -1;
}
stat = pmecc_readl(host->pmecc, isr);
if (stat != 0)
if (pmecc_correction(mtd, stat, buf, &oob[eccpos[0]]) != 0)
return -EIO;
return 0;
}
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;
int timeout = PMECC_MAX_TIMEOUT_US;
pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_RST);
pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_DISABLE);
pmecc_writel(host->pmecc, cfg, (pmecc_readl(host->pmecc, cfg) |
PMECC_CFG_WRITE_OP) & ~PMECC_CFG_AUTO_ENABLE);
pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_ENABLE);
pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_DATA);
chip->write_buf(mtd, (u8 *)buf, mtd->writesize);
while (--timeout) {
if (!(pmecc_readl(host->pmecc, sr) & PMECC_SR_BUSY))
break;
WATCHDOG_RESET();
udelay(1);
}
if (!timeout) {
printk(KERN_ERR "atmel_nand : Timeout to read PMECC status, fail to write PMECC in oob\n");
goto out;
}
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]] =
readb(&host->pmecc->ecc_port[i].ecc[j]);
}
}
chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
out:
return 0;
}
static void atmel_pmecc_core_init(struct mtd_info *mtd)
{
struct nand_chip *nand_chip = mtd->priv;
struct atmel_nand_host *host = nand_chip->priv;
uint32_t val = 0;
struct nand_ecclayout *ecc_layout;
pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_RST);
pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_DISABLE);
switch (host->pmecc_corr_cap) {
case 2:
val = PMECC_CFG_BCH_ERR2;
break;
case 4:
val = PMECC_CFG_BCH_ERR4;
break;
case 8:
val = PMECC_CFG_BCH_ERR8;
break;
case 12:
val = PMECC_CFG_BCH_ERR12;
break;
case 24:
val = PMECC_CFG_BCH_ERR24;
break;
}
if (host->pmecc_sector_size == 512)
val |= PMECC_CFG_SECTOR512;
else if (host->pmecc_sector_size == 1024)
val |= PMECC_CFG_SECTOR1024;
switch (host->pmecc_sector_number) {
case 1:
val |= PMECC_CFG_PAGE_1SECTOR;
break;
case 2:
val |= PMECC_CFG_PAGE_2SECTORS;
break;
case 4:
val |= PMECC_CFG_PAGE_4SECTORS;
break;
case 8:
val |= PMECC_CFG_PAGE_8SECTORS;
break;
}
val |= (PMECC_CFG_READ_OP | PMECC_CFG_SPARE_DISABLE
| PMECC_CFG_AUTO_DISABLE);
pmecc_writel(host->pmecc, cfg, val);
ecc_layout = nand_chip->ecc.layout;
pmecc_writel(host->pmecc, sarea, mtd->oobsize - 1);
pmecc_writel(host->pmecc, saddr, ecc_layout->eccpos[0]);
pmecc_writel(host->pmecc, eaddr,
ecc_layout->eccpos[ecc_layout->eccbytes - 1]);
/* See datasheet about PMECC Clock Control Register */
pmecc_writel(host->pmecc, clk, PMECC_CLK_133MHZ);
pmecc_writel(host->pmecc, idr, 0xff);
pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_ENABLE);
}
static int atmel_pmecc_nand_init_params(struct nand_chip *nand,
struct mtd_info *mtd)
{
struct atmel_nand_host *host;
int cap, sector_size;
host = nand->priv = &pmecc_host;
nand->ecc.mode = NAND_ECC_HW;
nand->ecc.calculate = NULL;
nand->ecc.correct = NULL;
nand->ecc.hwctl = NULL;
cap = host->pmecc_corr_cap = CONFIG_PMECC_CAP;
sector_size = host->pmecc_sector_size = CONFIG_PMECC_SECTOR_SIZE;
host->pmecc_index_table_offset = CONFIG_PMECC_INDEX_TABLE_OFFSET;
MTDDEBUG(MTD_DEBUG_LEVEL1,
"Initialize PMECC params, cap: %d, sector: %d\n",
cap, sector_size);
host->pmecc = (struct pmecc_regs __iomem *) ATMEL_BASE_PMECC;
host->pmerrloc = (struct pmecc_errloc_regs __iomem *)
ATMEL_BASE_PMERRLOC;
host->pmecc_rom_base = (void __iomem *) ATMEL_BASE_ROM;
/* ECC is calculated for the whole page (1 step) */
nand->ecc.size = mtd->writesize;
/* set ECC page size and oob layout */
switch (mtd->writesize) {
case 2048:
case 4096:
host->pmecc_degree = PMECC_GF_DIMENSION_13;
host->pmecc_cw_len = (1 << host->pmecc_degree) - 1;
host->pmecc_sector_number = mtd->writesize / sector_size;
host->pmecc_bytes_per_sector = pmecc_get_ecc_bytes(
cap, sector_size);
host->pmecc_alpha_to = pmecc_get_alpha_to(host);
host->pmecc_index_of = host->pmecc_rom_base +
host->pmecc_index_table_offset;
nand->ecc.steps = 1;
nand->ecc.bytes = host->pmecc_bytes_per_sector *
host->pmecc_sector_number;
if (nand->ecc.bytes > mtd->oobsize - 2) {
printk(KERN_ERR "No room for ECC bytes\n");
return -EINVAL;
}
pmecc_config_ecc_layout(&atmel_pmecc_oobinfo,
mtd->oobsize,
nand->ecc.bytes);
nand->ecc.layout = &atmel_pmecc_oobinfo;
break;
case 512:
case 1024:
/* TODO */
printk(KERN_ERR "Unsupported page size for PMECC, use Software ECC\n");
default:
/* page size not handled by HW ECC */
/* switching back to soft ECC */
nand->ecc.mode = NAND_ECC_SOFT;
nand->ecc.read_page = NULL;
nand->ecc.postpad = 0;
nand->ecc.prepad = 0;
nand->ecc.bytes = 0;
return 0;
}
nand->ecc.read_page = atmel_nand_pmecc_read_page;
nand->ecc.write_page = atmel_nand_pmecc_write_page;
nand->ecc.strength = cap;
atmel_pmecc_core_init(mtd);
return 0;
}
#else
/* 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}
},
};
/*
* Calculate HW ECC
*
* function called after a write
*
* mtd: MTD block structure
* dat: raw data (unused)
* ecc_code: buffer for ECC
*/
static int atmel_nand_calculate(struct mtd_info *mtd,
const u_char *dat, unsigned char *ecc_code)
{
unsigned int ecc_value;
/* get the first 2 ECC bytes */
ecc_value = ecc_readl(CONFIG_SYS_NAND_ECC_BASE, PR);
ecc_code[0] = ecc_value & 0xFF;
ecc_code[1] = (ecc_value >> 8) & 0xFF;
/* get the last 2 ECC bytes */
ecc_value = ecc_readl(CONFIG_SYS_NAND_ECC_BASE, NPR) & ATMEL_ECC_NPARITY;
ecc_code[2] = ecc_value & 0xFF;
ecc_code[3] = (ecc_value >> 8) & 0xFF;
return 0;
}
/*
* HW ECC read page function
*
* mtd: mtd info structure
* chip: nand chip info structure
* buf: buffer to store read data
* oob_required: caller expects OOB data read to chip->oob_poi
*/
static int atmel_nand_read_page(struct mtd_info *mtd, struct nand_chip *chip,
uint8_t *buf, int oob_required, int page)
{
int eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
uint32_t *eccpos = chip->ecc.layout->eccpos;
uint8_t *p = buf;
uint8_t *oob = chip->oob_poi;
uint8_t *ecc_pos;
int stat;
/* read the page */
chip->read_buf(mtd, p, eccsize);
/* move to ECC position if needed */
if (eccpos[0] != 0) {
/* This only works on large pages
* because the ECC controller waits for
* NAND_CMD_RNDOUTSTART after the
* NAND_CMD_RNDOUT.
* anyway, for small pages, the eccpos[0] == 0
*/
chip->cmdfunc(mtd, NAND_CMD_RNDOUT,
mtd->writesize + eccpos[0], -1);
}
/* the ECC controller needs to read the ECC just after the data */
ecc_pos = oob + eccpos[0];
chip->read_buf(mtd, ecc_pos, eccbytes);
/* check if there's an error */
stat = chip->ecc.correct(mtd, p, oob, NULL);
if (stat < 0)
mtd->ecc_stats.failed++;
else
mtd->ecc_stats.corrected += stat;
/* get back to oob start (end of page) */
chip->cmdfunc(mtd, NAND_CMD_RNDOUT, mtd->writesize, -1);
/* read the oob */
chip->read_buf(mtd, oob, mtd->oobsize);
return 0;
}
/*
* HW ECC Correction
*
* function called after a read
*
* mtd: MTD block structure
* dat: raw data read from the chip
* read_ecc: ECC from the chip (unused)
* isnull: unused
*
* Detect and correct a 1 bit error for a page
*/
static int atmel_nand_correct(struct mtd_info *mtd, u_char *dat,
u_char *read_ecc, u_char *isnull)
{
struct nand_chip *nand_chip = mtd->priv;
unsigned int ecc_status;
unsigned int ecc_word, ecc_bit;
/* get the status from the Status Register */
ecc_status = ecc_readl(CONFIG_SYS_NAND_ECC_BASE, SR);
/* if there's no error */
if (likely(!(ecc_status & ATMEL_ECC_RECERR)))
return 0;
/* get error bit offset (4 bits) */
ecc_bit = ecc_readl(CONFIG_SYS_NAND_ECC_BASE, PR) & ATMEL_ECC_BITADDR;
/* get word address (12 bits) */
ecc_word = ecc_readl(CONFIG_SYS_NAND_ECC_BASE, PR) & ATMEL_ECC_WORDADDR;
ecc_word >>= 4;
/* if there are multiple errors */
if (ecc_status & ATMEL_ECC_MULERR) {
/* check if it is a freshly erased block
* (filled with 0xff) */
if ((ecc_bit == ATMEL_ECC_BITADDR)
&& (ecc_word == (ATMEL_ECC_WORDADDR >> 4))) {
/* the block has just been erased, return OK */
return 0;
}
/* it doesn't seems to be a freshly
* erased block.
* We can't correct so many errors */
printk(KERN_WARNING "atmel_nand : multiple errors detected."
" Unable to correct.\n");
return -EIO;
}
/* if there's a single bit error : we can correct it */
if (ecc_status & ATMEL_ECC_ECCERR) {
/* there's nothing much to do here.
* the bit error is on the ECC itself.
*/
printk(KERN_WARNING "atmel_nand : one bit error on ECC code."
" Nothing to correct\n");
return 0;
}
printk(KERN_WARNING "atmel_nand : one bit error on data."
" (word offset in the page :"
" 0x%x bit offset : 0x%x)\n",
ecc_word, ecc_bit);
/* correct the error */
if (nand_chip->options & NAND_BUSWIDTH_16) {
/* 16 bits words */
((unsigned short *) dat)[ecc_word] ^= (1 << ecc_bit);
} else {
/* 8 bits words */
dat[ecc_word] ^= (1 << ecc_bit);
}
printk(KERN_WARNING "atmel_nand : error corrected\n");
return 1;
}
/*
* Enable HW ECC : unused on most chips
*/
static void atmel_nand_hwctl(struct mtd_info *mtd, int mode)
{
}
int atmel_hwecc_nand_init_param(struct nand_chip *nand, struct mtd_info *mtd)
{
nand->ecc.mode = NAND_ECC_HW;
nand->ecc.calculate = atmel_nand_calculate;
nand->ecc.correct = atmel_nand_correct;
nand->ecc.hwctl = atmel_nand_hwctl;
nand->ecc.read_page = atmel_nand_read_page;
nand->ecc.bytes = 4;
if (nand->ecc.mode == NAND_ECC_HW) {
/* ECC is calculated for the whole page (1 step) */
nand->ecc.size = mtd->writesize;
/* set ECC page size and oob layout */
switch (mtd->writesize) {
case 512:
nand->ecc.layout = &atmel_oobinfo_small;
ecc_writel(CONFIG_SYS_NAND_ECC_BASE, MR,
ATMEL_ECC_PAGESIZE_528);
break;
case 1024:
nand->ecc.layout = &atmel_oobinfo_large;
ecc_writel(CONFIG_SYS_NAND_ECC_BASE, MR,
ATMEL_ECC_PAGESIZE_1056);
break;
case 2048:
nand->ecc.layout = &atmel_oobinfo_large;
ecc_writel(CONFIG_SYS_NAND_ECC_BASE, MR,
ATMEL_ECC_PAGESIZE_2112);
break;
case 4096:
nand->ecc.layout = &atmel_oobinfo_large;
ecc_writel(CONFIG_SYS_NAND_ECC_BASE, MR,
ATMEL_ECC_PAGESIZE_4224);
break;
default:
/* page size not handled by HW ECC */
/* switching back to soft ECC */
nand->ecc.mode = NAND_ECC_SOFT;
nand->ecc.calculate = NULL;
nand->ecc.correct = NULL;
nand->ecc.hwctl = NULL;
nand->ecc.read_page = NULL;
nand->ecc.postpad = 0;
nand->ecc.prepad = 0;
nand->ecc.bytes = 0;
break;
}
}
return 0;
}
#endif /* CONFIG_ATMEL_NAND_HW_PMECC */
#endif /* CONFIG_ATMEL_NAND_HWECC */
static void at91_nand_hwcontrol(struct mtd_info *mtd,
int cmd, unsigned int ctrl)
{
struct nand_chip *this = mtd->priv;
if (ctrl & NAND_CTRL_CHANGE) {
ulong IO_ADDR_W = (ulong) this->IO_ADDR_W;
IO_ADDR_W &= ~(CONFIG_SYS_NAND_MASK_ALE
| CONFIG_SYS_NAND_MASK_CLE);
if (ctrl & NAND_CLE)
IO_ADDR_W |= CONFIG_SYS_NAND_MASK_CLE;
if (ctrl & NAND_ALE)
IO_ADDR_W |= CONFIG_SYS_NAND_MASK_ALE;
#ifdef CONFIG_SYS_NAND_ENABLE_PIN
at91_set_gpio_value(CONFIG_SYS_NAND_ENABLE_PIN,
!(ctrl & NAND_NCE));
#endif
this->IO_ADDR_W = (void *) IO_ADDR_W;
}
if (cmd != NAND_CMD_NONE)
writeb(cmd, this->IO_ADDR_W);
}
#ifdef CONFIG_SYS_NAND_READY_PIN
static int at91_nand_ready(struct mtd_info *mtd)
{
return at91_get_gpio_value(CONFIG_SYS_NAND_READY_PIN);
}
#endif
#ifndef CONFIG_SYS_NAND_BASE_LIST
#define CONFIG_SYS_NAND_BASE_LIST { CONFIG_SYS_NAND_BASE }
#endif
static struct nand_chip nand_chip[CONFIG_SYS_MAX_NAND_DEVICE];
static ulong base_addr[CONFIG_SYS_MAX_NAND_DEVICE] = CONFIG_SYS_NAND_BASE_LIST;
int atmel_nand_chip_init(int devnum, ulong base_addr)
{
int ret;
struct mtd_info *mtd = &nand_info[devnum];
struct nand_chip *nand = &nand_chip[devnum];
mtd->priv = nand;
nand->IO_ADDR_R = nand->IO_ADDR_W = (void __iomem *)base_addr;
nand->ecc.mode = NAND_ECC_SOFT;
#ifdef CONFIG_SYS_NAND_DBW_16
nand->options = NAND_BUSWIDTH_16;
#endif
nand->cmd_ctrl = at91_nand_hwcontrol;
#ifdef CONFIG_SYS_NAND_READY_PIN
nand->dev_ready = at91_nand_ready;
#endif
nand->chip_delay = 20;
ret = nand_scan_ident(mtd, CONFIG_SYS_NAND_MAX_CHIPS, NULL);
if (ret)
return ret;
#ifdef CONFIG_ATMEL_NAND_HWECC
#ifdef CONFIG_ATMEL_NAND_HW_PMECC
ret = atmel_pmecc_nand_init_params(nand, mtd);
#else
ret = atmel_hwecc_nand_init_param(nand, mtd);
#endif
if (ret)
return ret;
#endif
ret = nand_scan_tail(mtd);
if (!ret)
nand_register(devnum);
return ret;
}
void board_nand_init(void)
{
int i;
for (i = 0; i < CONFIG_SYS_MAX_NAND_DEVICE; i++)
if (atmel_nand_chip_init(i, base_addr[i]))
printk(KERN_ERR "atmel_nand: Fail to initialize #%d chip",
i);
}