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 rogerq@kernel.org --- 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 b36fe762b3..b5ad66ad49 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 */ @@ -187,72 +190,35 @@ 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); }
/* @@ -271,6 +237,124 @@ 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); @@ -279,17 +363,11 @@ 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--; @@ -301,23 +379,24 @@ 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; @@ -330,18 +409,18 @@ 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; @@ -351,6 +430,22 @@ 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); @@ -475,6 +570,35 @@ 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 @@ -627,52 +751,49 @@ 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 */ @@ -820,9 +941,9 @@ 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; @@ -861,9 +982,9 @@ 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; @@ -894,9 +1015,9 @@ 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;