diff options
Diffstat (limited to 'drivers/mtd')
-rw-r--r-- | drivers/mtd/nand/davinci_nand.c | 218 |
1 files changed, 13 insertions, 205 deletions
diff --git a/drivers/mtd/nand/davinci_nand.c b/drivers/mtd/nand/davinci_nand.c index 8b22024..9e7b9dd 100644 --- a/drivers/mtd/nand/davinci_nand.c +++ b/drivers/mtd/nand/davinci_nand.c @@ -86,45 +86,12 @@ static void nand_davinci_select_chip(struct mtd_info *mtd, int chip) } #ifdef CONFIG_SYS_NAND_HW_ECC -#ifdef CONFIG_SYS_DAVINCI_BROKEN_ECC -/* Linux-compatible ECC uses MTD defaults. */ -/* These layouts are not compatible with Linux or RBL/UBL. */ -#ifdef CONFIG_SYS_NAND_LARGEPAGE -static struct nand_ecclayout davinci_nand_ecclayout = { - .eccbytes = 12, - .eccpos = {8, 9, 10, 24, 25, 26, 40, 41, 42, 56, 57, 58}, - .oobfree = { - {.offset = 2, .length = 6}, - {.offset = 12, .length = 12}, - {.offset = 28, .length = 12}, - {.offset = 44, .length = 12}, - {.offset = 60, .length = 4} - } -}; -#elif defined(CONFIG_SYS_NAND_SMALLPAGE) -static struct nand_ecclayout davinci_nand_ecclayout = { - .eccbytes = 3, - .eccpos = {0, 1, 2}, - .oobfree = { - {.offset = 6, .length = 2}, - {.offset = 8, .length = 8} - } -}; -#else -#error "Either CONFIG_SYS_NAND_LARGEPAGE or CONFIG_SYS_NAND_SMALLPAGE must be defined!" -#endif -#endif /* CONFIG_SYS_DAVINCI_BROKEN_ECC */ static void nand_davinci_enable_hwecc(struct mtd_info *mtd, int mode) { int dummy; dummy = emif_regs->NANDF1ECC; -#ifdef CONFIG_SYS_DAVINCI_BROKEN_ECC - dummy = emif_regs->NANDF2ECC; - dummy = emif_regs->NANDF3ECC; - dummy = emif_regs->NANDF4ECC; -#endif /* FIXME: only chipselect 0 is supported for now */ emif_regs->NANDFCR |= 1 << 8; @@ -149,29 +116,6 @@ static u_int32_t nand_davinci_readecc(struct mtd_info *mtd, u_int32_t region) static int nand_davinci_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_char *ecc_code) { u_int32_t tmp; -#ifdef CONFIG_SYS_DAVINCI_BROKEN_ECC - /* - * This is not how you should read ECCs on large page Davinci devices. - * The region parameter gets you ECCs for flash chips on different chip - * selects, not the 4x512 byte pages in a 2048 byte page. - * - * Preserved for backwards compatibility though. - */ - - int region, n; - struct nand_chip *this = mtd->priv; - - n = (this->ecc.size/512); - - region = 1; - while (n--) { - tmp = nand_davinci_readecc(mtd, region); - *ecc_code++ = tmp; - *ecc_code++ = tmp >> 16; - *ecc_code++ = ((tmp >> 8) & 0x0f) | ((tmp >> 20) & 0xf0); - region++; - } -#else const int region = 1; tmp = nand_davinci_readecc(mtd, region); @@ -186,148 +130,26 @@ static int nand_davinci_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u *ecc_code++ = tmp; *ecc_code++ = tmp >> 8; *ecc_code++ = tmp >> 16; -#endif /* CONFIG_SYS_DAVINCI_BROKEN_ECC */ - return(0); -} - -#ifdef CONFIG_SYS_DAVINCI_BROKEN_ECC -static void nand_davinci_gen_true_ecc(u_int8_t *ecc_buf) -{ - u_int32_t tmp = ecc_buf[0] | (ecc_buf[1] << 16) | ((ecc_buf[2] & 0xf0) << 20) | ((ecc_buf[2] & 0x0f) << 8); - - ecc_buf[0] = ~(P64o(tmp) | P64e(tmp) | P32o(tmp) | P32e(tmp) | P16o(tmp) | P16e(tmp) | P8o(tmp) | P8e(tmp)); - ecc_buf[1] = ~(P1024o(tmp) | P1024e(tmp) | P512o(tmp) | P512e(tmp) | P256o(tmp) | P256e(tmp) | P128o(tmp) | P128e(tmp)); - ecc_buf[2] = ~( P4o(tmp) | P4e(tmp) | P2o(tmp) | P2e(tmp) | P1o(tmp) | P1e(tmp) | P2048o(tmp) | P2048e(tmp)); -} - -static int nand_davinci_compare_ecc(u_int8_t *ecc_nand, u_int8_t *ecc_calc, u_int8_t *page_data) -{ - u_int32_t i; - u_int8_t tmp0_bit[8], tmp1_bit[8], tmp2_bit[8]; - u_int8_t comp0_bit[8], comp1_bit[8], comp2_bit[8]; - u_int8_t ecc_bit[24]; - u_int8_t ecc_sum = 0; - u_int8_t find_bit = 0; - u_int32_t find_byte = 0; - int is_ecc_ff; - - is_ecc_ff = ((*ecc_nand == 0xff) && (*(ecc_nand + 1) == 0xff) && (*(ecc_nand + 2) == 0xff)); - - nand_davinci_gen_true_ecc(ecc_nand); - nand_davinci_gen_true_ecc(ecc_calc); - - for (i = 0; i <= 2; i++) { - *(ecc_nand + i) = ~(*(ecc_nand + i)); - *(ecc_calc + i) = ~(*(ecc_calc + i)); - } - - for (i = 0; i < 8; i++) { - tmp0_bit[i] = *ecc_nand % 2; - *ecc_nand = *ecc_nand / 2; - } - - for (i = 0; i < 8; i++) { - tmp1_bit[i] = *(ecc_nand + 1) % 2; - *(ecc_nand + 1) = *(ecc_nand + 1) / 2; - } - - for (i = 0; i < 8; i++) { - tmp2_bit[i] = *(ecc_nand + 2) % 2; - *(ecc_nand + 2) = *(ecc_nand + 2) / 2; - } - for (i = 0; i < 8; i++) { - comp0_bit[i] = *ecc_calc % 2; - *ecc_calc = *ecc_calc / 2; - } - - for (i = 0; i < 8; i++) { - comp1_bit[i] = *(ecc_calc + 1) % 2; - *(ecc_calc + 1) = *(ecc_calc + 1) / 2; - } - - for (i = 0; i < 8; i++) { - comp2_bit[i] = *(ecc_calc + 2) % 2; - *(ecc_calc + 2) = *(ecc_calc + 2) / 2; - } - - for (i = 0; i< 6; i++) - ecc_bit[i] = tmp2_bit[i + 2] ^ comp2_bit[i + 2]; - - for (i = 0; i < 8; i++) - ecc_bit[i + 6] = tmp0_bit[i] ^ comp0_bit[i]; - - for (i = 0; i < 8; i++) - ecc_bit[i + 14] = tmp1_bit[i] ^ comp1_bit[i]; - - ecc_bit[22] = tmp2_bit[0] ^ comp2_bit[0]; - ecc_bit[23] = tmp2_bit[1] ^ comp2_bit[1]; - - for (i = 0; i < 24; i++) - ecc_sum += ecc_bit[i]; + /* NOTE: the above code matches mainline Linux: + * .PQR.stu ==> ~PQRstu + * + * MontaVista/TI kernels encode those bytes differently, use + * complicated (and allegedly sometimes-wrong) correction code, + * and usually shipped with U-Boot that uses software ECC: + * .PQR.stu ==> PsQRtu + * + * If you need MV/TI compatible NAND I/O in U-Boot, it should + * be possible to (a) change the mangling above, (b) reverse + * that mangling in nand_davinci_correct_data() below. + */ - switch (ecc_sum) { - case 0: - /* Not reached because this function is not called if - ECC values are equal */ - return 0; - case 1: - /* Uncorrectable error */ - MTDDEBUG (MTD_DEBUG_LEVEL0, - "ECC UNCORRECTED_ERROR 1\n"); - return(-1); - case 12: - /* Correctable error */ - find_byte = (ecc_bit[23] << 8) + - (ecc_bit[21] << 7) + - (ecc_bit[19] << 6) + - (ecc_bit[17] << 5) + - (ecc_bit[15] << 4) + - (ecc_bit[13] << 3) + - (ecc_bit[11] << 2) + - (ecc_bit[9] << 1) + - ecc_bit[7]; - - find_bit = (ecc_bit[5] << 2) + (ecc_bit[3] << 1) + ecc_bit[1]; - - MTDDEBUG (MTD_DEBUG_LEVEL0, "Correcting single bit ECC " - "error at offset: %d, bit: %d\n", - find_byte, find_bit); - - page_data[find_byte] ^= (1 << find_bit); - - return(0); - default: - if (is_ecc_ff) { - if (ecc_calc[0] == 0 && ecc_calc[1] == 0 && ecc_calc[2] == 0) - return(0); - } - MTDDEBUG (MTD_DEBUG_LEVEL0, - "UNCORRECTED_ERROR default\n"); - return(-1); - } + return 0; } -#endif /* CONFIG_SYS_DAVINCI_BROKEN_ECC */ static int nand_davinci_correct_data(struct mtd_info *mtd, u_char *dat, u_char *read_ecc, u_char *calc_ecc) { struct nand_chip *this = mtd->priv; -#ifdef CONFIG_SYS_DAVINCI_BROKEN_ECC - int block_count = 0, i, rc; - - block_count = (this->ecc.size/512); - for (i = 0; i < block_count; i++) { - if (memcmp(read_ecc, calc_ecc, 3) != 0) { - rc = nand_davinci_compare_ecc(read_ecc, calc_ecc, dat); - if (rc < 0) { - return(rc); - } - } - read_ecc += 3; - calc_ecc += 3; - dat += 512; - } -#else u_int32_t ecc_nand = read_ecc[0] | (read_ecc[1] << 8) | (read_ecc[2] << 16); u_int32_t ecc_calc = calc_ecc[0] | (calc_ecc[1] << 8) | @@ -361,7 +183,6 @@ static int nand_davinci_correct_data(struct mtd_info *mtd, u_char *dat, u_char * return -1; } } -#endif /* CONFIG_SYS_DAVINCI_BROKEN_ECC */ return(0); } #endif /* CONFIG_SYS_NAND_HW_ECC */ @@ -416,21 +237,8 @@ int board_nand_init(struct nand_chip *nand) #endif #ifdef CONFIG_SYS_NAND_HW_ECC nand->ecc.mode = NAND_ECC_HW; -#ifdef CONFIG_SYS_DAVINCI_BROKEN_ECC - nand->ecc.layout = &davinci_nand_ecclayout; -#ifdef CONFIG_SYS_NAND_LARGEPAGE - nand->ecc.size = 2048; - nand->ecc.bytes = 12; -#elif defined(CONFIG_SYS_NAND_SMALLPAGE) - nand->ecc.size = 512; - nand->ecc.bytes = 3; -#else -#error "Either CONFIG_SYS_NAND_LARGEPAGE or CONFIG_SYS_NAND_SMALLPAGE must be defined!" -#endif -#else nand->ecc.size = 512; nand->ecc.bytes = 3; -#endif /* CONFIG_SYS_DAVINCI_BROKEN_ECC */ nand->ecc.calculate = nand_davinci_calculate_ecc; nand->ecc.correct = nand_davinci_correct_data; nand->ecc.hwctl = nand_davinci_enable_hwecc; |