The BCH detection hardware can generate ECC bytes for multiple
sectors in one go. Use that feature.
correct() only corrects one sector at a time so we need to call it
repeatedly for each sector.
Signed-off-by: Roger Quadros <rog...@kernel.org>
Reviewed-by: Michael Trimarchi <mich...@amarulasolutions.com>
---
drivers/mtd/nand/raw/omap_gpmc.c | 325 +++++++++++++++++++++----------
1 file changed, 223 insertions(+), 102 deletions(-)
diff --git a/drivers/mtd/nand/raw/omap_gpmc.c b/drivers/mtd/nand/raw/omap_gpmc.c
index 69fc09be097..e772a914c88 100644
--- a/drivers/mtd/nand/raw/omap_gpmc.c
+++ b/drivers/mtd/nand/raw/omap_gpmc.c
@@ -27,6 +27,9 @@
#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 */
@@ -186,72 +189,35 @@ static int __maybe_unused omap_correct_data(struct
mtd_info *mtd, uint8_t *dat,
__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);
+ 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;
- unsigned int ecc_algo = 0;
- unsigned int bch_type = 0;
- unsigned int eccsize1 = 0x00, eccsize0 = 0x00, bch_wrapmode = 0x00;
- u32 ecc_size_config_val = 0;
- u32 ecc_config_val = 0;
- int cs = info->cs;
+ u32 val;
- /* configure GPMC for specific ecc-scheme */
- switch (info->ecc_scheme) {
- case OMAP_ECC_HAM1_CODE_SW:
- return;
- case OMAP_ECC_HAM1_CODE_HW:
- ecc_algo = 0x0;
- bch_type = 0x0;
- bch_wrapmode = 0x00;
- eccsize0 = 0xFF;
- eccsize1 = 0xFF;
+ /* 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 OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
- case OMAP_ECC_BCH8_CODE_HW:
- ecc_algo = 0x1;
- bch_type = 0x1;
- if (mode == NAND_ECC_WRITE) {
- bch_wrapmode = 0x01;
- eccsize0 = 0; /* extra bits in nibbles per sector */
- eccsize1 = 28; /* OOB bits in nibbles per sector */
- } else {
- bch_wrapmode = 0x01;
- eccsize0 = 26; /* ECC bits in nibbles per sector */
- eccsize1 = 2; /* non-ECC bits in nibbles per sector */
- }
- break;
- case OMAP_ECC_BCH16_CODE_HW:
- ecc_algo = 0x1;
- bch_type = 0x2;
- if (mode == NAND_ECC_WRITE) {
- bch_wrapmode = 0x01;
- eccsize0 = 0; /* extra bits in nibbles per sector */
- eccsize1 = 52; /* OOB bits in nibbles per sector */
- } else {
- bch_wrapmode = 0x01;
- eccsize0 = 52; /* ECC bits in nibbles per sector */
- eccsize1 = 0; /* non-ECC bits in nibbles per sector */
- }
+ case NAND_ECC_READSYN:
+ writel(ECCCLEAR, &gpmc_cfg->ecc_control);
break;
default:
- return;
+ printf("%s: error: unrecognized Mode[%d]!\n", __func__, mode);
+ break;
}
- /* Clear ecc and enable bits */
- writel(ECCCLEAR | ECCRESULTREG1, &gpmc_cfg->ecc_control);
- /* Configure ecc size for BCH */
- ecc_size_config_val = (eccsize1 << 22) | (eccsize0 << 12);
- writel(ecc_size_config_val, &gpmc_cfg->ecc_size_config);
-
- /* Configure device details for BCH engine */
- ecc_config_val = ((ecc_algo << 16) | /* HAM1 | BCHx */
- (bch_type << 12) | /* BCH4/BCH8/BCH16 */
- (bch_wrapmode << 8) | /* wrap mode */
- (dev_width << 7) | /* bus width */
- (0x0 << 4) | /* number of sectors */
- (cs << 1) | /* ECC CS */
- (0x1)); /* enable ECC */
- writel(ecc_config_val, &gpmc_cfg->ecc_config);
+
+ /* (ECC 16 or 8 bit col) | ( CS ) | ECC Enable */
+ val = (dev_width << 7) | (info->cs << 1) | (0x1);
+ writel(val, &gpmc_cfg->ecc_config);
}
/*
@@ -270,6 +236,124 @@ static void omap_enable_hwecc(struct mtd_info *mtd,
int32_t mode)
*/
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);
@@ -278,17 +362,11 @@ static int omap_calculate_ecc(struct mtd_info *mtd, const
uint8_t *dat,
int8_t i = 0, j;
switch (info->ecc_scheme) {
- case OMAP_ECC_HAM1_CODE_HW:
- 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);
- break;
#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[0].bch_result_x[3];
+ ptr = &gpmc_cfg->bch_result_0_3[sector].bch_result_x[3];
val = readl(ptr);
ecc_code[i++] = (val >> 0) & 0xFF;
ptr--;
@@ -300,23 +378,24 @@ static int omap_calculate_ecc(struct mtd_info *mtd, const
uint8_t *dat,
ecc_code[i++] = (val >> 0) & 0xFF;
ptr--;
}
+
break;
case OMAP_ECC_BCH16_CODE_HW:
- val = readl(&gpmc_cfg->bch_result_4_6[0].bch_result_x[2]);
+ 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[0].bch_result_x[1]);
+ 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[0].bch_result_x[0]);
+ 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[0].bch_result_x[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;
@@ -329,18 +408,18 @@ static int omap_calculate_ecc(struct mtd_info *mtd, const
uint8_t *dat,
}
/* ECC scheme specific syndrome customizations */
switch (info->ecc_scheme) {
- case OMAP_ECC_HAM1_CODE_HW:
- break;
#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) = *(ecc_code + i) ^
- bch8_polynomial[i];
+ ecc_code[i] ^= bch8_polynomial[i];
break;
#endif
case OMAP_ECC_BCH8_CODE_HW:
- ecc_code[chip->ecc.bytes - 1] = 0x00;
+ /* Set 14th ECC byte as 0x0 for ROM compatibility */
+ ecc_code[chip->ecc.bytes - 1] = 0x0;
break;
case OMAP_ECC_BCH16_CODE_HW:
break;
@@ -350,6 +429,22 @@ static int omap_calculate_ecc(struct mtd_info *mtd, const
uint8_t *dat,
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 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);
@@ -474,6 +569,35 @@ static void omap_nand_read_prefetch(struct mtd_info *mtd,
uint8_t *buf, int len)
#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
@@ -626,52 +750,49 @@ static int omap_read_page_bch(struct mtd_info *mtd,
struct nand_chip *chip,
{
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 data_pos;
uint32_t oob_pos;
- data_pos = 0;
/* oob area start */
oob_pos = (eccsize * eccsteps) + chip->ecc.layout->eccpos[0];
oob += chip->ecc.layout->eccpos[0];
- for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize,
- oob += eccbytes) {
- chip->ecc.hwctl(mtd, NAND_ECC_READ);
- /* read data */
- chip->cmdfunc(mtd, NAND_CMD_RNDOUT, data_pos, -1);
- chip->read_buf(mtd, p, eccsize);
-
- /* read respective ecc from oob area */
- chip->cmdfunc(mtd, NAND_CMD_RNDOUT, oob_pos, -1);
- chip->read_buf(mtd, oob, eccbytes);
- /* read syndrome */
- chip->ecc.calculate(mtd, p, &ecc_calc[i]);
-
- data_pos += eccsize;
- oob_pos += eccbytes;
- }
+ /* 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 */
@@ -819,9 +940,9 @@ static int omap_select_ecc_scheme(struct nand_chip *nand,
nand->ecc.strength = 8;
nand->ecc.size = SECTOR_BYTES;
nand->ecc.bytes = 13;
- nand->ecc.hwctl = omap_enable_hwecc;
+ nand->ecc.hwctl = omap_enable_hwecc_bch;
nand->ecc.correct = omap_correct_data_bch_sw;
- nand->ecc.calculate = omap_calculate_ecc;
+ nand->ecc.calculate = omap_calculate_ecc_bch;
/* define ecc-layout */
ecclayout->eccbytes = nand->ecc.bytes * eccsteps;
ecclayout->eccpos[0] = BADBLOCK_MARKER_LENGTH;
@@ -860,9 +981,9 @@ static int omap_select_ecc_scheme(struct nand_chip *nand,
nand->ecc.strength = 8;
nand->ecc.size = SECTOR_BYTES;
nand->ecc.bytes = 14;
- nand->ecc.hwctl = omap_enable_hwecc;
+ nand->ecc.hwctl = omap_enable_hwecc_bch;
nand->ecc.correct = omap_correct_data_bch;
- nand->ecc.calculate = omap_calculate_ecc;
+ nand->ecc.calculate = omap_calculate_ecc_bch;
nand->ecc.read_page = omap_read_page_bch;
/* define ecc-layout */
ecclayout->eccbytes = nand->ecc.bytes * eccsteps;
@@ -893,9 +1014,9 @@ static int omap_select_ecc_scheme(struct nand_chip *nand,
nand->ecc.size = SECTOR_BYTES;
nand->ecc.bytes = 26;
nand->ecc.strength = 16;
- nand->ecc.hwctl = omap_enable_hwecc;
+ nand->ecc.hwctl = omap_enable_hwecc_bch;
nand->ecc.correct = omap_correct_data_bch;
- nand->ecc.calculate = omap_calculate_ecc;
+ nand->ecc.calculate = omap_calculate_ecc_bch;
nand->ecc.read_page = omap_read_page_bch;
/* define ecc-layout */
ecclayout->eccbytes = nand->ecc.bytes * eccsteps;
--
2.34.1
