blob: 4d5f2455df3e247a9c9f4a3824ac988603a75c75 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2004-2008 Texas Instruments, <www.ti.com>
* Rohit Choraria <rohitkc@ti.com>
*/
#include <common.h>
#include <log.h>
#include <asm/io.h>
#include <dm/uclass.h>
#include <linux/errno.h>
#ifdef CONFIG_ARCH_OMAP2PLUS
#include <asm/arch/mem.h>
#endif
#include <linux/mtd/omap_gpmc.h>
#include <linux/mtd/nand_ecc.h>
#include <linux/mtd/rawnand.h>
#include <linux/bch.h>
#include <linux/compiler.h>
#include <nand.h>
#include <linux/mtd/omap_elm.h>
#ifndef GPMC_MAX_CS
#define GPMC_MAX_CS 4
#endif
#define BADBLOCK_MARKER_LENGTH 2
#define SECTOR_BYTES 512
#define ECCSIZE0_SHIFT 12
#define ECCSIZE1_SHIFT 22
#define ECC1RESULTSIZE 0x1
#define ECCCLEAR (0x1 << 8)
#define ECCRESULTREG1 (0x1 << 0)
/* 4 bit padding to make byte aligned, 56 = 52 + 4 */
#define BCH4_BIT_PAD 4
#ifdef CONFIG_BCH
static u8 bch8_polynomial[] = {0xef, 0x51, 0x2e, 0x09, 0xed, 0x93, 0x9a, 0xc2,
0x97, 0x79, 0xe5, 0x24, 0xb5};
#endif
static uint8_t cs_next;
#if defined(CONFIG_NAND_OMAP_GPMC_WSCFG)
static const int8_t wscfg[CONFIG_SYS_MAX_NAND_DEVICE] =
{ CONFIG_NAND_OMAP_GPMC_WSCFG };
#else
/* wscfg is preset to zero since its a static variable */
static const int8_t wscfg[CONFIG_SYS_MAX_NAND_DEVICE];
#endif
/*
* Driver configurations
*/
struct omap_nand_info {
struct bch_control *control;
enum omap_ecc ecc_scheme;
uint8_t cs;
uint8_t ws; /* wait status pin (0,1) */
void __iomem *fifo;
};
/* We are wasting a bit of memory but al least we are safe */
static struct omap_nand_info omap_nand_info[GPMC_MAX_CS];
/*
* omap_nand_hwcontrol - Set the address pointers corretly for the
* following address/data/command operation
*/
static void omap_nand_hwcontrol(struct mtd_info *mtd, int32_t cmd,
uint32_t ctrl)
{
register struct nand_chip *this = mtd_to_nand(mtd);
struct omap_nand_info *info = nand_get_controller_data(this);
int cs = info->cs;
/*
* Point the IO_ADDR to DATA and ADDRESS registers instead
* of chip address
*/
switch (ctrl) {
case NAND_CTRL_CHANGE | NAND_CTRL_CLE:
this->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_cmd;
break;
case NAND_CTRL_CHANGE | NAND_CTRL_ALE:
this->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_adr;
break;
case NAND_CTRL_CHANGE | NAND_NCE:
this->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_dat;
break;
}
if (cmd != NAND_CMD_NONE)
writeb(cmd, this->IO_ADDR_W);
}
/* Check wait pin as dev ready indicator */
static int omap_dev_ready(struct mtd_info *mtd)
{
register struct nand_chip *this = mtd_to_nand(mtd);
struct omap_nand_info *info = nand_get_controller_data(this);
return gpmc_cfg->status & (1 << (8 + info->ws));
}
/*
* gen_true_ecc - This function will generate true ECC value, which
* can be used when correcting data read from NAND flash memory core
*
* @ecc_buf: buffer to store ecc code
*
* @return: re-formatted ECC value
*/
static uint32_t gen_true_ecc(uint8_t *ecc_buf)
{
return ecc_buf[0] | (ecc_buf[1] << 16) | ((ecc_buf[2] & 0xF0) << 20) |
((ecc_buf[2] & 0x0F) << 8);
}
/*
* omap_correct_data - Compares the ecc read from nand spare area with ECC
* registers values and corrects one bit error if it has occurred
* Further details can be had from OMAP TRM and the following selected links:
* http://en.wikipedia.org/wiki/Hamming_code
* http://www.cs.utexas.edu/users/plaxton/c/337/05f/slides/ErrorCorrection-4.pdf
*
* @mtd: MTD device structure
* @dat: page data
* @read_ecc: ecc read from nand flash
* @calc_ecc: ecc read from ECC registers
*
* Return: 0 if data is OK or corrected, else returns -1
*/
static int __maybe_unused omap_correct_data(struct mtd_info *mtd, uint8_t *dat,
uint8_t *read_ecc, uint8_t *calc_ecc)
{
uint32_t orig_ecc, new_ecc, res, hm;
uint16_t parity_bits, byte;
uint8_t bit;
/* Regenerate the orginal ECC */
orig_ecc = gen_true_ecc(read_ecc);
new_ecc = gen_true_ecc(calc_ecc);
/* Get the XOR of real ecc */
res = orig_ecc ^ new_ecc;
if (res) {
/* Get the hamming width */
hm = hweight32(res);
/* Single bit errors can be corrected! */
if (hm == 12) {
/* Correctable data! */
parity_bits = res >> 16;
bit = (parity_bits & 0x7);
byte = (parity_bits >> 3) & 0x1FF;
/* Flip the bit to correct */
dat[byte] ^= (0x1 << bit);
} else if (hm == 1) {
printf("Error: Ecc is wrong\n");
/* ECC itself is corrupted */
return 2;
} else {
/*
* hm distance != parity pairs OR one, could mean 2 bit
* error OR potentially be on a blank page..
* orig_ecc: contains spare area data from nand flash.
* new_ecc: generated ecc while reading data area.
* Note: if the ecc = 0, all data bits from which it was
* generated are 0xFF.
* The 3 byte(24 bits) ecc is generated per 512byte
* chunk of a page. If orig_ecc(from spare area)
* is 0xFF && new_ecc(computed now from data area)=0x0,
* this means that data area is 0xFF and spare area is
* 0xFF. A sure sign of a erased page!
*/
if ((orig_ecc == 0x0FFF0FFF) && (new_ecc == 0x00000000))
return 0;
printf("Error: Bad compare! failed\n");
/* detected 2 bit error */
return -EBADMSG;
}
}
return 0;
}
/*
* omap_enable_hwecc - configures GPMC as per ECC scheme before read/write
* @mtd: MTD device structure
* @mode: Read/Write mode
*/
__maybe_unused
static void omap_enable_hwecc(struct mtd_info *mtd, int32_t mode)
{
struct nand_chip *nand = mtd_to_nand(mtd);
struct omap_nand_info *info = nand_get_controller_data(nand);
unsigned int dev_width = (nand->options & NAND_BUSWIDTH_16) ? 1 : 0;
u32 val;
/* Clear ecc and enable bits */
writel(ECCCLEAR | ECCRESULTREG1, &gpmc_cfg->ecc_control);
/* program ecc and result sizes */
val = ((((nand->ecc.size >> 1) - 1) << ECCSIZE1_SHIFT) |
ECC1RESULTSIZE);
writel(val, &gpmc_cfg->ecc_size_config);
switch (mode) {
case NAND_ECC_READ:
case NAND_ECC_WRITE:
writel(ECCCLEAR | ECCRESULTREG1, &gpmc_cfg->ecc_control);
break;
case NAND_ECC_READSYN:
writel(ECCCLEAR, &gpmc_cfg->ecc_control);
break;
default:
printf("%s: error: unrecognized Mode[%d]!\n", __func__, mode);
break;
}
/* (ECC 16 or 8 bit col) | ( CS ) | ECC Enable */
val = (dev_width << 7) | (info->cs << 1) | (0x1);
writel(val, &gpmc_cfg->ecc_config);
}
/*
* omap_calculate_ecc - Read ECC result
* @mtd: MTD structure
* @dat: unused
* @ecc_code: 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.
* E.g. if page is 0xFF (fresh erased), and if HW ECC engine within GPMC
* is used, the result of read will be 0x0 while the ECC offsets of the
* spare area will be 0xFF which will result in an ECC mismatch.
*/
static int omap_calculate_ecc(struct mtd_info *mtd, const uint8_t *dat,
uint8_t *ecc_code)
{
u32 val;
val = readl(&gpmc_cfg->ecc1_result);
ecc_code[0] = val & 0xFF;
ecc_code[1] = (val >> 16) & 0xFF;
ecc_code[2] = ((val >> 8) & 0x0F) | ((val >> 20) & 0xF0);
return 0;
}
/* GPMC ecc engine settings for read */
#define BCH_WRAPMODE_1 1 /* BCH wrap mode 1 */
#define BCH8R_ECC_SIZE0 0x1a /* ecc_size0 = 26 */
#define BCH8R_ECC_SIZE1 0x2 /* ecc_size1 = 2 */
#define BCH4R_ECC_SIZE0 0xd /* ecc_size0 = 13 */
#define BCH4R_ECC_SIZE1 0x3 /* ecc_size1 = 3 */
/* GPMC ecc engine settings for write */
#define BCH_WRAPMODE_6 6 /* BCH wrap mode 6 */
#define BCH_ECC_SIZE0 0x0 /* ecc_size0 = 0, no oob protection */
#define BCH_ECC_SIZE1 0x20 /* ecc_size1 = 32 */
/**
* omap_enable_hwecc_bch - Program GPMC to perform BCH ECC calculation
* @mtd: MTD device structure
* @mode: Read/Write mode
*
* When using BCH with SW correction (i.e. no ELM), sector size is set
* to 512 bytes and we use BCH_WRAPMODE_6 wrapping mode
* for both reading and writing with:
* eccsize0 = 0 (no additional protected byte in spare area)
* eccsize1 = 32 (skip 32 nibbles = 16 bytes per sector in spare area)
*/
static void __maybe_unused omap_enable_hwecc_bch(struct mtd_info *mtd,
int mode)
{
unsigned int bch_type;
unsigned int dev_width, nsectors;
struct nand_chip *chip = mtd_to_nand(mtd);
struct omap_nand_info *info = nand_get_controller_data(chip);
u32 val, wr_mode;
unsigned int ecc_size1, ecc_size0;
/* GPMC configurations for calculating ECC */
switch (info->ecc_scheme) {
case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
bch_type = 1;
nsectors = 1;
wr_mode = BCH_WRAPMODE_6;
ecc_size0 = BCH_ECC_SIZE0;
ecc_size1 = BCH_ECC_SIZE1;
break;
case OMAP_ECC_BCH8_CODE_HW:
bch_type = 1;
nsectors = chip->ecc.steps;
if (mode == NAND_ECC_READ) {
wr_mode = BCH_WRAPMODE_1;
ecc_size0 = BCH8R_ECC_SIZE0;
ecc_size1 = BCH8R_ECC_SIZE1;
} else {
wr_mode = BCH_WRAPMODE_6;
ecc_size0 = BCH_ECC_SIZE0;
ecc_size1 = BCH_ECC_SIZE1;
}
break;
case OMAP_ECC_BCH16_CODE_HW:
bch_type = 0x2;
nsectors = chip->ecc.steps;
if (mode == NAND_ECC_READ) {
wr_mode = 0x01;
ecc_size0 = 52; /* ECC bits in nibbles per sector */
ecc_size1 = 0; /* non-ECC bits in nibbles per sector */
} else {
wr_mode = 0x01;
ecc_size0 = 0; /* extra bits in nibbles per sector */
ecc_size1 = 52; /* OOB bits in nibbles per sector */
}
break;
default:
return;
}
writel(ECCRESULTREG1, &gpmc_cfg->ecc_control);
/* Configure ecc size for BCH */
val = (ecc_size1 << ECCSIZE1_SHIFT) | (ecc_size0 << ECCSIZE0_SHIFT);
writel(val, &gpmc_cfg->ecc_size_config);
dev_width = (chip->options & NAND_BUSWIDTH_16) ? 1 : 0;
/* BCH configuration */
val = ((1 << 16) | /* enable BCH */
(bch_type << 12) | /* BCH4/BCH8/BCH16 */
(wr_mode << 8) | /* wrap mode */
(dev_width << 7) | /* bus width */
(((nsectors - 1) & 0x7) << 4) | /* number of sectors */
(info->cs << 1) | /* ECC CS */
(0x1)); /* enable ECC */
writel(val, &gpmc_cfg->ecc_config);
/* Clear ecc and enable bits */
writel(ECCCLEAR | ECCRESULTREG1, &gpmc_cfg->ecc_control);
}
/**
* _omap_calculate_ecc_bch - Generate BCH ECC bytes for one sector
* @mtd: MTD device structure
* @dat: The pointer to data on which ecc is computed
* @ecc_code: The ecc_code buffer
* @sector: The sector number (for a multi sector page)
*
* Support calculating of BCH4/8/16 ECC vectors for one sector
* within a page. Sector number is in @sector.
*/
static int _omap_calculate_ecc_bch(struct mtd_info *mtd, const u8 *dat,
u8 *ecc_code, int sector)
{
struct nand_chip *chip = mtd_to_nand(mtd);
struct omap_nand_info *info = nand_get_controller_data(chip);
const uint32_t *ptr;
uint32_t val = 0;
int8_t i = 0, j;
switch (info->ecc_scheme) {
#ifdef CONFIG_BCH
case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
#endif
case OMAP_ECC_BCH8_CODE_HW:
ptr = &gpmc_cfg->bch_result_0_3[sector].bch_result_x[3];
val = readl(ptr);
ecc_code[i++] = (val >> 0) & 0xFF;
ptr--;
for (j = 0; j < 3; j++) {
val = readl(ptr);
ecc_code[i++] = (val >> 24) & 0xFF;
ecc_code[i++] = (val >> 16) & 0xFF;
ecc_code[i++] = (val >> 8) & 0xFF;
ecc_code[i++] = (val >> 0) & 0xFF;
ptr--;
}
break;
case OMAP_ECC_BCH16_CODE_HW:
val = readl(&gpmc_cfg->bch_result_4_6[sector].bch_result_x[2]);
ecc_code[i++] = (val >> 8) & 0xFF;
ecc_code[i++] = (val >> 0) & 0xFF;
val = readl(&gpmc_cfg->bch_result_4_6[sector].bch_result_x[1]);
ecc_code[i++] = (val >> 24) & 0xFF;
ecc_code[i++] = (val >> 16) & 0xFF;
ecc_code[i++] = (val >> 8) & 0xFF;
ecc_code[i++] = (val >> 0) & 0xFF;
val = readl(&gpmc_cfg->bch_result_4_6[sector].bch_result_x[0]);
ecc_code[i++] = (val >> 24) & 0xFF;
ecc_code[i++] = (val >> 16) & 0xFF;
ecc_code[i++] = (val >> 8) & 0xFF;
ecc_code[i++] = (val >> 0) & 0xFF;
for (j = 3; j >= 0; j--) {
val = readl(&gpmc_cfg->bch_result_0_3[sector].bch_result_x[j]
);
ecc_code[i++] = (val >> 24) & 0xFF;
ecc_code[i++] = (val >> 16) & 0xFF;
ecc_code[i++] = (val >> 8) & 0xFF;
ecc_code[i++] = (val >> 0) & 0xFF;
}
break;
default:
return -EINVAL;
}
/* ECC scheme specific syndrome customizations */
switch (info->ecc_scheme) {
#ifdef CONFIG_BCH
case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
/* Add constant polynomial to remainder, so that
* ECC of blank pages results in 0x0 on reading back
*/
for (i = 0; i < chip->ecc.bytes; i++)
ecc_code[i] ^= bch8_polynomial[i];
break;
#endif
case OMAP_ECC_BCH8_CODE_HW:
/* Set 14th ECC byte as 0x0 for ROM compatibility */
ecc_code[chip->ecc.bytes - 1] = 0x0;
break;
case OMAP_ECC_BCH16_CODE_HW:
break;
default:
return -EINVAL;
}
return 0;
}
/**
* omap_calculate_ecc_bch - ECC generator for 1 sector
* @mtd: MTD device structure
* @dat: The pointer to data on which ecc is computed
* @ecc_code: The ecc_code buffer
*
* Support calculating of BCH4/8/16 ECC vectors for one sector. This is used
* when SW based correction is required as ECC is required for one sector
* at a time.
*/
static int __maybe_unused omap_calculate_ecc_bch(struct mtd_info *mtd,
const u_char *dat, u_char *ecc_calc)
{
return _omap_calculate_ecc_bch(mtd, dat, ecc_calc, 0);
}
static inline void omap_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
{
struct nand_chip *chip = mtd_to_nand(mtd);
struct omap_nand_info *info = nand_get_controller_data(chip);
u32 alignment = ((uintptr_t)buf | len) & 3;
if (alignment & 1)
readsb(info->fifo, buf, len);
else if (alignment & 3)
readsw(info->fifo, buf, len >> 1);
else
readsl(info->fifo, buf, len >> 2);
}
#ifdef CONFIG_NAND_OMAP_GPMC_PREFETCH
#define PREFETCH_CONFIG1_CS_SHIFT 24
#define PREFETCH_FIFOTHRESHOLD_MAX 0x40
#define PREFETCH_FIFOTHRESHOLD(val) ((val) << 8)
#define PREFETCH_STATUS_COUNT(val) (val & 0x00003fff)
#define PREFETCH_STATUS_FIFO_CNT(val) ((val >> 24) & 0x7F)
#define ENABLE_PREFETCH (1 << 7)
/**
* omap_prefetch_enable - configures and starts prefetch transfer
* @fifo_th: fifo threshold to be used for read/ write
* @count: number of bytes to be transferred
* @is_write: prefetch read(0) or write post(1) mode
* @cs: chip select to use
*/
static int omap_prefetch_enable(int fifo_th, unsigned int count, int is_write, int cs)
{
uint32_t val;
if (fifo_th > PREFETCH_FIFOTHRESHOLD_MAX)
return -EINVAL;
if (readl(&gpmc_cfg->prefetch_control))
return -EBUSY;
/* Set the amount of bytes to be prefetched */
writel(count, &gpmc_cfg->prefetch_config2);
val = (cs << PREFETCH_CONFIG1_CS_SHIFT) | (is_write & 1) |
PREFETCH_FIFOTHRESHOLD(fifo_th) | ENABLE_PREFETCH;
writel(val, &gpmc_cfg->prefetch_config1);
/* Start the prefetch engine */
writel(1, &gpmc_cfg->prefetch_control);
return 0;
}
/**
* omap_prefetch_reset - disables and stops the prefetch engine
*/
static void omap_prefetch_reset(void)
{
writel(0, &gpmc_cfg->prefetch_control);
writel(0, &gpmc_cfg->prefetch_config1);
}
static int __read_prefetch_aligned(struct nand_chip *chip, uint32_t *buf, int len)
{
int ret;
uint32_t cnt;
struct omap_nand_info *info = nand_get_controller_data(chip);
ret = omap_prefetch_enable(PREFETCH_FIFOTHRESHOLD_MAX, len, 0, info->cs);
if (ret < 0)
return ret;
do {
int i;
cnt = readl(&gpmc_cfg->prefetch_status);
cnt = PREFETCH_STATUS_FIFO_CNT(cnt);
for (i = 0; i < cnt / 4; i++) {
*buf++ = readl(info->fifo);
len -= 4;
}
} while (len);
omap_prefetch_reset();
return 0;
}
static void omap_nand_read_prefetch(struct mtd_info *mtd, uint8_t *buf, int len)
{
int ret;
uintptr_t head, tail;
struct nand_chip *chip = mtd_to_nand(mtd);
/*
* If the destination buffer is unaligned, start with reading
* the overlap byte-wise.
*/
head = ((uintptr_t)buf) % 4;
if (head) {
omap_nand_read_buf(mtd, buf, head);
buf += head;
len -= head;
}
/*
* Only transfer multiples of 4 bytes in a pre-fetched fashion.
* If there's a residue, care for it byte-wise afterwards.
*/
tail = len % 4;
ret = __read_prefetch_aligned(chip, (uint32_t *)buf, len - tail);
if (ret < 0) {
/* fallback in case the prefetch engine is busy */
omap_nand_read_buf(mtd, buf, len);
} else if (tail) {
buf += len - tail;
omap_nand_read_buf(mtd, buf, tail);
}
}
#endif /* CONFIG_NAND_OMAP_GPMC_PREFETCH */
#ifdef CONFIG_NAND_OMAP_ELM
/**
* omap_calculate_ecc_bch_multi - Generate ECC for multiple sectors
* @mtd: MTD device structure
* @dat: The pointer to data on which ecc is computed
* @ecc_code: The ecc_code buffer
*
* Support calculating of BCH4/8/16 ecc vectors for the entire page in one go.
*/
static int omap_calculate_ecc_bch_multi(struct mtd_info *mtd,
const u_char *dat, u_char *ecc_calc)
{
struct nand_chip *chip = mtd_to_nand(mtd);
int eccbytes = chip->ecc.bytes;
unsigned long nsectors;
int i, ret;
nsectors = ((readl(&gpmc_cfg->ecc_config) >> 4) & 0x7) + 1;
for (i = 0; i < nsectors; i++) {
ret = _omap_calculate_ecc_bch(mtd, dat, ecc_calc, i);
if (ret)
return ret;
ecc_calc += eccbytes;
}
return 0;
}
/*
* omap_reverse_list - re-orders list elements in reverse order [internal]
* @list: pointer to start of list
* @length: length of list
*/
static void omap_reverse_list(u8 *list, unsigned int length)
{
unsigned int i, j;
unsigned int half_length = length / 2;
u8 tmp;
for (i = 0, j = length - 1; i < half_length; i++, j--) {
tmp = list[i];
list[i] = list[j];
list[j] = tmp;
}
}
/*
* omap_correct_data_bch - Compares the ecc read from nand spare area
* with ECC registers values and corrects one bit error if it has occurred
*
* @mtd: MTD device structure
* @dat: page data
* @read_ecc: ecc read from nand flash (ignored)
* @calc_ecc: ecc read from ECC registers
*
* Return: 0 if data is OK or corrected, else returns -1
*/
static int omap_correct_data_bch(struct mtd_info *mtd, uint8_t *dat,
uint8_t *read_ecc, uint8_t *calc_ecc)
{
struct nand_chip *chip = mtd_to_nand(mtd);
struct omap_nand_info *info = nand_get_controller_data(chip);
struct nand_ecc_ctrl *ecc = &chip->ecc;
uint32_t error_count = 0, error_max;
uint32_t error_loc[ELM_MAX_ERROR_COUNT];
enum bch_level bch_type;
uint32_t i, ecc_flag = 0;
uint8_t count;
uint32_t byte_pos, bit_pos;
int err = 0;
/* check calculated ecc */
for (i = 0; i < ecc->bytes && !ecc_flag; i++) {
if (calc_ecc[i] != 0x00)
goto not_ecc_match;
}
return 0;
not_ecc_match:
/* check for whether it's an erased-page */
for (i = 0; i < ecc->bytes; i++) {
if (read_ecc[i] != 0xff)
goto not_erased;
}
for (i = 0; i < SECTOR_BYTES; i++) {
if (dat[i] != 0xff)
goto not_erased;
}
return 0;
not_erased:
/*
* Check for whether it's an erased page with a correctable
* number of bitflips. Erased pages have all 1's in the data,
* so we just compute the number of 0 bits in the data and
* see if it's under the correction threshold.
*
* NOTE: The check for a perfect erased page above is faster for
* the more common case, even though it's logically redundant.
*/
for (i = 0; i < ecc->bytes; i++)
error_count += hweight8(~read_ecc[i]);
for (i = 0; i < SECTOR_BYTES; i++)
error_count += hweight8(~dat[i]);
if (error_count <= ecc->strength) {
memset(read_ecc, 0xFF, ecc->bytes);
memset(dat, 0xFF, SECTOR_BYTES);
debug("nand: %u bit-flip(s) corrected in erased page\n",
error_count);
return error_count;
}
/*
* while reading ECC result we read it in big endian.
* Hence while loading to ELM we have rotate to get the right endian.
*/
switch (info->ecc_scheme) {
case OMAP_ECC_BCH8_CODE_HW:
bch_type = BCH_8_BIT;
omap_reverse_list(calc_ecc, ecc->bytes - 1);
break;
case OMAP_ECC_BCH16_CODE_HW:
bch_type = BCH_16_BIT;
omap_reverse_list(calc_ecc, ecc->bytes);
break;
default:
return -EINVAL;
}
/* use elm module to check for errors */
elm_config(bch_type);
error_count = 0;
err = elm_check_error(calc_ecc, bch_type, &error_count, error_loc);
if (err)
return err;
/* correct bch error */
for (count = 0; count < error_count; count++) {
switch (info->ecc_scheme) {
case OMAP_ECC_BCH8_CODE_HW:
/* 14th byte in ECC is reserved to match ROM layout */
error_max = SECTOR_BYTES + (ecc->bytes - 1);
break;
case OMAP_ECC_BCH16_CODE_HW:
error_max = SECTOR_BYTES + ecc->bytes;
break;
default:
return -EINVAL;
}
byte_pos = error_max - (error_loc[count] / 8) - 1;
bit_pos = error_loc[count] % 8;
if (byte_pos < SECTOR_BYTES) {
dat[byte_pos] ^= 1 << bit_pos;
debug("nand: bit-flip corrected @data=%d\n", byte_pos);
} else if (byte_pos < error_max) {
read_ecc[byte_pos - SECTOR_BYTES] ^= 1 << bit_pos;
debug("nand: bit-flip corrected @oob=%d\n", byte_pos -
SECTOR_BYTES);
} else {
err = -EBADMSG;
printf("nand: error: invalid bit-flip location\n");
}
}
return (err) ? err : error_count;
}
/**
* omap_read_page_bch - hardware ecc based page read 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
* @page: page number to read
*
*/
static int omap_read_page_bch(struct mtd_info *mtd, struct nand_chip *chip,
uint8_t *buf, int oob_required, int page)
{
int i, eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
int ecctotal = chip->ecc.total;
int eccsteps = chip->ecc.steps;
uint8_t *p = buf;
uint8_t *ecc_calc = chip->buffers->ecccalc;
uint8_t *ecc_code = chip->buffers->ecccode;
uint32_t *eccpos = chip->ecc.layout->eccpos;
uint8_t *oob = chip->oob_poi;
uint32_t oob_pos;
/* oob area start */
oob_pos = (eccsize * eccsteps) + chip->ecc.layout->eccpos[0];
oob += chip->ecc.layout->eccpos[0];
/* Enable ECC engine */
chip->ecc.hwctl(mtd, NAND_ECC_READ);
/* read entire page */
chip->cmdfunc(mtd, NAND_CMD_RNDOUT, 0, -1);
chip->read_buf(mtd, buf, mtd->writesize);
/* read all ecc bytes from oob area */
chip->cmdfunc(mtd, NAND_CMD_RNDOUT, oob_pos, -1);
chip->read_buf(mtd, oob, ecctotal);
/* Calculate ecc bytes */
omap_calculate_ecc_bch_multi(mtd, buf, ecc_calc);
for (i = 0; i < chip->ecc.total; i++)
ecc_code[i] = chip->oob_poi[eccpos[i]];
/* error detect & correct */
eccsteps = chip->ecc.steps;
p = buf;
for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
int stat;
stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
if (stat < 0)
mtd->ecc_stats.failed++;
else
mtd->ecc_stats.corrected += stat;
}
return 0;
}
#endif /* CONFIG_NAND_OMAP_ELM */
/*
* OMAP3 BCH8 support (with BCH library)
*/
#ifdef CONFIG_BCH
/**
* omap_correct_data_bch_sw - Decode received data and correct errors
* @mtd: MTD device structure
* @data: page data
* @read_ecc: ecc read from nand flash
* @calc_ecc: ecc read from HW ECC registers
*/
static int omap_correct_data_bch_sw(struct mtd_info *mtd, u_char *data,
u_char *read_ecc, u_char *calc_ecc)
{
int i, count;
/* cannot correct more than 8 errors */
unsigned int errloc[8];
struct nand_chip *chip = mtd_to_nand(mtd);
struct omap_nand_info *info = nand_get_controller_data(chip);
count = decode_bch(info->control, NULL, SECTOR_BYTES,
read_ecc, calc_ecc, NULL, errloc);
if (count > 0) {
/* correct errors */
for (i = 0; i < count; i++) {
/* correct data only, not ecc bytes */
if (errloc[i] < SECTOR_BYTES << 3)
data[errloc[i] >> 3] ^= 1 << (errloc[i] & 7);
debug("corrected bitflip %u\n", errloc[i]);
#ifdef DEBUG
puts("read_ecc: ");
/*
* BCH8 have 13 bytes of ECC; BCH4 needs adoption
* here!
*/
for (i = 0; i < 13; i++)
printf("%02x ", read_ecc[i]);
puts("\n");
puts("calc_ecc: ");
for (i = 0; i < 13; i++)
printf("%02x ", calc_ecc[i]);
puts("\n");
#endif
}
} else if (count < 0) {
puts("ecc unrecoverable error\n");
}
return count;
}
/**
* omap_free_bch - Release BCH ecc resources
* @mtd: MTD device structure
*/
static void __maybe_unused omap_free_bch(struct mtd_info *mtd)
{
struct nand_chip *chip = mtd_to_nand(mtd);
struct omap_nand_info *info = nand_get_controller_data(chip);
if (info->control) {
free_bch(info->control);
info->control = NULL;
}
}
#endif /* CONFIG_BCH */
/**
* omap_select_ecc_scheme - configures driver for particular ecc-scheme
* @nand: NAND chip device structure
* @ecc_scheme: ecc scheme to configure
* @pagesize: number of main-area bytes per page of NAND device
* @oobsize: number of OOB/spare bytes per page of NAND device
*/
static int omap_select_ecc_scheme(struct nand_chip *nand,
enum omap_ecc ecc_scheme, unsigned int pagesize, unsigned int oobsize) {
struct omap_nand_info *info = nand_get_controller_data(nand);
struct nand_ecclayout *ecclayout = nand->ecc.layout;
int eccsteps = pagesize / SECTOR_BYTES;
int i;
switch (ecc_scheme) {
case OMAP_ECC_HAM1_CODE_SW:
debug("nand: selected OMAP_ECC_HAM1_CODE_SW\n");
/* For this ecc-scheme, ecc.bytes, ecc.layout, ... are
* initialized in nand_scan_tail(), so just set ecc.mode */
info->control = NULL;
nand->ecc.mode = NAND_ECC_SOFT;
nand->ecc.layout = NULL;
nand->ecc.size = 0;
break;
case OMAP_ECC_HAM1_CODE_HW:
debug("nand: selected OMAP_ECC_HAM1_CODE_HW\n");
/* check ecc-scheme requirements before updating ecc info */
if ((3 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) {
printf("nand: error: insufficient OOB: require=%d\n", (
(3 * eccsteps) + BADBLOCK_MARKER_LENGTH));
return -EINVAL;
}
info->control = NULL;
/* populate ecc specific fields */
memset(&nand->ecc, 0, sizeof(struct nand_ecc_ctrl));
nand->ecc.mode = NAND_ECC_HW;
nand->ecc.strength = 1;
nand->ecc.size = SECTOR_BYTES;
nand->ecc.bytes = 3;
nand->ecc.hwctl = omap_enable_hwecc;
nand->ecc.correct = omap_correct_data;
nand->ecc.calculate = omap_calculate_ecc;
/* define ecc-layout */
ecclayout->eccbytes = nand->ecc.bytes * eccsteps;
for (i = 0; i < ecclayout->eccbytes; i++) {
if (nand->options & NAND_BUSWIDTH_16)
ecclayout->eccpos[i] = i + 2;
else
ecclayout->eccpos[i] = i + 1;
}
ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH;
ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes -
BADBLOCK_MARKER_LENGTH;
break;
case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
#ifdef CONFIG_BCH
debug("nand: selected OMAP_ECC_BCH8_CODE_HW_DETECTION_SW\n");
/* check ecc-scheme requirements before updating ecc info */
if ((13 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) {
printf("nand: error: insufficient OOB: require=%d\n", (
(13 * eccsteps) + BADBLOCK_MARKER_LENGTH));
return -EINVAL;
}
/* check if BCH S/W library can be used for error detection */
info->control = init_bch(13, 8, 0x201b);
if (!info->control) {
printf("nand: error: could not init_bch()\n");
return -ENODEV;
}
/* populate ecc specific fields */
memset(&nand->ecc, 0, sizeof(struct nand_ecc_ctrl));
nand->ecc.mode = NAND_ECC_HW;
nand->ecc.strength = 8;
nand->ecc.size = SECTOR_BYTES;
nand->ecc.bytes = 13;
nand->ecc.hwctl = omap_enable_hwecc_bch;
nand->ecc.correct = omap_correct_data_bch_sw;
nand->ecc.calculate = omap_calculate_ecc_bch;
/* define ecc-layout */
ecclayout->eccbytes = nand->ecc.bytes * eccsteps;
ecclayout->eccpos[0] = BADBLOCK_MARKER_LENGTH;
for (i = 1; i < ecclayout->eccbytes; i++) {
if (i % nand->ecc.bytes)
ecclayout->eccpos[i] =
ecclayout->eccpos[i - 1] + 1;
else
ecclayout->eccpos[i] =
ecclayout->eccpos[i - 1] + 2;
}
ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH;
ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes -
BADBLOCK_MARKER_LENGTH;
break;
#else
printf("nand: error: CONFIG_BCH required for ECC\n");
return -EINVAL;
#endif
case OMAP_ECC_BCH8_CODE_HW:
#ifdef CONFIG_NAND_OMAP_ELM
debug("nand: selected OMAP_ECC_BCH8_CODE_HW\n");
/* check ecc-scheme requirements before updating ecc info */
if ((14 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) {
printf("nand: error: insufficient OOB: require=%d\n", (
(14 * eccsteps) + BADBLOCK_MARKER_LENGTH));
return -EINVAL;
}
/* intialize ELM for ECC error detection */
elm_init();
info->control = NULL;
/* populate ecc specific fields */
memset(&nand->ecc, 0, sizeof(struct nand_ecc_ctrl));
nand->ecc.mode = NAND_ECC_HW;
nand->ecc.strength = 8;
nand->ecc.size = SECTOR_BYTES;
nand->ecc.bytes = 14;
nand->ecc.hwctl = omap_enable_hwecc_bch;
nand->ecc.correct = omap_correct_data_bch;
nand->ecc.calculate = omap_calculate_ecc_bch;
nand->ecc.read_page = omap_read_page_bch;
/* define ecc-layout */
ecclayout->eccbytes = nand->ecc.bytes * eccsteps;
for (i = 0; i < ecclayout->eccbytes; i++)
ecclayout->eccpos[i] = i + BADBLOCK_MARKER_LENGTH;
ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH;
ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes -
BADBLOCK_MARKER_LENGTH;
break;
#else
printf("nand: error: CONFIG_NAND_OMAP_ELM required for ECC\n");
return -EINVAL;
#endif
case OMAP_ECC_BCH16_CODE_HW:
#ifdef CONFIG_NAND_OMAP_ELM
debug("nand: using OMAP_ECC_BCH16_CODE_HW\n");
/* check ecc-scheme requirements before updating ecc info */
if ((26 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) {
printf("nand: error: insufficient OOB: require=%d\n", (
(26 * eccsteps) + BADBLOCK_MARKER_LENGTH));
return -EINVAL;
}
/* intialize ELM for ECC error detection */
elm_init();
/* populate ecc specific fields */
nand->ecc.mode = NAND_ECC_HW;
nand->ecc.size = SECTOR_BYTES;
nand->ecc.bytes = 26;
nand->ecc.strength = 16;
nand->ecc.hwctl = omap_enable_hwecc_bch;
nand->ecc.correct = omap_correct_data_bch;
nand->ecc.calculate = omap_calculate_ecc_bch;
nand->ecc.read_page = omap_read_page_bch;
/* define ecc-layout */
ecclayout->eccbytes = nand->ecc.bytes * eccsteps;
for (i = 0; i < ecclayout->eccbytes; i++)
ecclayout->eccpos[i] = i + BADBLOCK_MARKER_LENGTH;
ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH;
ecclayout->oobfree[0].length = oobsize - nand->ecc.bytes -
BADBLOCK_MARKER_LENGTH;
break;
#else
printf("nand: error: CONFIG_NAND_OMAP_ELM required for ECC\n");
return -EINVAL;
#endif
default:
debug("nand: error: ecc scheme not enabled or supported\n");
return -EINVAL;
}
/* nand_scan_tail() sets ham1 sw ecc; hw ecc layout is set by driver */
if (ecc_scheme != OMAP_ECC_HAM1_CODE_SW)
nand->ecc.layout = ecclayout;
info->ecc_scheme = ecc_scheme;
return 0;
}
#ifndef CONFIG_SPL_BUILD
/*
* omap_nand_switch_ecc - switch the ECC operation between different engines
* (h/w and s/w) and different algorithms (hamming and BCHx)
*
* @hardware - true if one of the HW engines should be used
* @eccstrength - the number of bits that could be corrected
* (1 - hamming, 4 - BCH4, 8 - BCH8, 16 - BCH16)
*/
int __maybe_unused omap_nand_switch_ecc(uint32_t hardware, uint32_t eccstrength)
{
struct nand_chip *nand;
struct mtd_info *mtd = get_nand_dev_by_index(nand_curr_device);
int err = 0;
if (!mtd) {
printf("nand: error: no NAND devices found\n");
return -ENODEV;
}
nand = mtd_to_nand(mtd);
nand->options |= NAND_OWN_BUFFERS;
nand->options &= ~NAND_SUBPAGE_READ;
/* Setup the ecc configurations again */
if (hardware) {
if (eccstrength == 1) {
err = omap_select_ecc_scheme(nand,
OMAP_ECC_HAM1_CODE_HW,
mtd->writesize, mtd->oobsize);
} else if (eccstrength == 8) {
err = omap_select_ecc_scheme(nand,
OMAP_ECC_BCH8_CODE_HW,
mtd->writesize, mtd->oobsize);
} else if (eccstrength == 16) {
err = omap_select_ecc_scheme(nand,
OMAP_ECC_BCH16_CODE_HW,
mtd->writesize, mtd->oobsize);
} else {
printf("nand: error: unsupported ECC scheme\n");
return -EINVAL;
}
} else {
if (eccstrength == 1) {
err = omap_select_ecc_scheme(nand,
OMAP_ECC_HAM1_CODE_SW,
mtd->writesize, mtd->oobsize);
} else if (eccstrength == 8) {
err = omap_select_ecc_scheme(nand,
OMAP_ECC_BCH8_CODE_HW_DETECTION_SW,
mtd->writesize, mtd->oobsize);
} else {
printf("nand: error: unsupported ECC scheme\n");
return -EINVAL;
}
}
/* Update NAND handling after ECC mode switch */
if (!err)
err = nand_scan_tail(mtd);
return err;
}
#endif /* CONFIG_SPL_BUILD */
/*
* Board-specific NAND initialization. The following members of the
* argument are board-specific:
* - IO_ADDR_R: address to read the 8 I/O lines of the flash device
* - IO_ADDR_W: address to write the 8 I/O lines of the flash device
* - cmd_ctrl: hardwarespecific function for accesing control-lines
* - waitfunc: hardwarespecific function for accesing device ready/busy line
* - ecc.hwctl: function to enable (reset) hardware ecc generator
* - ecc.mode: mode of ecc, see defines
* - chip_delay: chip dependent delay for transfering data from array to
* read regs (tR)
* - options: various chip options. They can partly be set to inform
* nand_scan about special functionality. See the defines for further
* explanation
*/
int gpmc_nand_init(struct nand_chip *nand)
{
int32_t gpmc_config = 0;
int cs = cs_next++;
int err = 0;
struct omap_nand_info *info;
/*
* xloader/Uboot's gpmc configuration would have configured GPMC for
* nand type of memory. The following logic scans and latches on to the
* first CS with NAND type memory.
* TBD: need to make this logic generic to handle multiple CS NAND
* devices.
*/
while (cs < GPMC_MAX_CS) {
/* Check if NAND type is set */
if ((readl(&gpmc_cfg->cs[cs].config1) & 0xC00) == 0x800) {
/* Found it!! */
break;
}
cs++;
}
if (cs >= GPMC_MAX_CS) {
printf("nand: error: Unable to find NAND settings in "
"GPMC Configuration - quitting\n");
return -ENODEV;
}
gpmc_config = readl(&gpmc_cfg->config);
/* Disable Write protect */
gpmc_config |= 0x10;
writel(gpmc_config, &gpmc_cfg->config);
nand->IO_ADDR_R = (void __iomem *)&gpmc_cfg->cs[cs].nand_dat;
nand->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_cmd;
info = &omap_nand_info[cs];
info->control = NULL;
info->cs = cs;
info->ws = wscfg[cs];
info->fifo = (void __iomem *)CFG_SYS_NAND_BASE;
nand_set_controller_data(nand, &omap_nand_info[cs]);
nand->cmd_ctrl = omap_nand_hwcontrol;
nand->options |= NAND_NO_PADDING | NAND_CACHEPRG;
nand->chip_delay = 100;
nand->ecc.layout = kzalloc(sizeof(*nand->ecc.layout), GFP_KERNEL);
if (!nand->ecc.layout)
return -ENOMEM;
/* configure driver and controller based on NAND device bus-width */
gpmc_config = readl(&gpmc_cfg->cs[cs].config1);
#if defined(CONFIG_SYS_NAND_BUSWIDTH_16BIT)
nand->options |= NAND_BUSWIDTH_16;
writel(gpmc_config | (0x1 << 12), &gpmc_cfg->cs[cs].config1);
#else
nand->options &= ~NAND_BUSWIDTH_16;
writel(gpmc_config & ~(0x1 << 12), &gpmc_cfg->cs[cs].config1);
#endif
/* select ECC scheme */
#if defined(CONFIG_NAND_OMAP_ECCSCHEME)
err = omap_select_ecc_scheme(nand, CONFIG_NAND_OMAP_ECCSCHEME,
CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE);
#else
/* pagesize and oobsize are not required to configure sw ecc-scheme */
err = omap_select_ecc_scheme(nand, OMAP_ECC_HAM1_CODE_SW,
0, 0);
#endif
if (err)
return err;
#ifdef CONFIG_NAND_OMAP_GPMC_PREFETCH
nand->read_buf = omap_nand_read_prefetch;
#else
nand->read_buf = omap_nand_read_buf;
#endif
nand->dev_ready = omap_dev_ready;
return 0;
}
/* First NAND chip for SPL use only */
static __maybe_unused struct nand_chip *nand_chip;
#if CONFIG_IS_ENABLED(SYS_NAND_SELF_INIT)
static int gpmc_nand_probe(struct udevice *dev)
{
struct nand_chip *nand = dev_get_priv(dev);
struct mtd_info *mtd = nand_to_mtd(nand);
int ret;
gpmc_nand_init(nand);
ret = nand_scan(mtd, CONFIG_SYS_NAND_MAX_CHIPS);
if (ret)
return ret;
ret = nand_register(0, mtd);
if (ret)
return ret;
if (!nand_chip)
nand_chip = nand;
return 0;
}
static const struct udevice_id gpmc_nand_ids[] = {
{ .compatible = "ti,am64-nand" },
{ .compatible = "ti,omap2-nand" },
{ }
};
U_BOOT_DRIVER(gpmc_nand) = {
.name = "gpmc-nand",
.id = UCLASS_MTD,
.of_match = gpmc_nand_ids,
.probe = gpmc_nand_probe,
.priv_auto = sizeof(struct nand_chip),
};
void board_nand_init(void)
{
struct udevice *dev;
int ret;
ret = uclass_get_device_by_driver(UCLASS_MTD,
DM_DRIVER_GET(gpmc_nand), &dev);
if (ret && ret != -ENODEV)
pr_err("%s: Failed to get GPMC device: %d\n", __func__, ret);
}
#else
int board_nand_init(struct nand_chip *nand)
{
return gpmc_nand_init(nand);
}
#endif /* CONFIG_SYS_NAND_SELF_INIT */
#if defined(CONFIG_SPL_NAND_INIT)
/* nand_init() is provided by nand.c */
/* Unselect after operation */
void nand_deselect(void)
{
struct mtd_info *mtd = nand_to_mtd(nand_chip);
if (nand_chip->select_chip)
nand_chip->select_chip(mtd, -1);
}
static int nand_is_bad_block(int block)
{
struct mtd_info *mtd = nand_to_mtd(nand_chip);
loff_t ofs = block * CONFIG_SYS_NAND_BLOCK_SIZE;
return nand_chip->block_bad(mtd, ofs);
}
static int nand_read_page(int block, int page, uchar *dst)
{
int page_addr = block * CONFIG_SYS_NAND_PAGE_COUNT + page;
loff_t ofs = page_addr * CONFIG_SYS_NAND_PAGE_SIZE;
int ret;
size_t len = CONFIG_SYS_NAND_PAGE_SIZE;
struct mtd_info *mtd = nand_to_mtd(nand_chip);
ret = nand_read(mtd, ofs, &len, dst);
if (ret)
printf("nand_read failed %d\n", ret);
return ret;
}
#include "nand_spl_loaders.c"
#endif /* CONFIG_SPL_NAND_INIT */