Messages in this thread Patch in this message |  | | From | Jane Wan <> | Subject | [PATCH 2/2] Use bit-wise majority to recover the contents of ONFI parameter | Date | Thu, 26 Apr 2018 17:19:56 -0700 |
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Signed-off-by: Jane Wan <Jane.Wan@nokia.com> --- drivers/mtd/nand/nand_base.c | 35 +++++++++++++++++++++++++++++++---- 1 file changed, 31 insertions(+), 4 deletions(-)
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index c2e1232..161b523 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -3153,8 +3153,10 @@ static int nand_flash_detect_onfi(struct mtd_info *mtd, struct nand_chip *chip, int *busw) { struct nand_onfi_params *p = &chip->onfi_params; - int i, j; - int val; + int i, j, k, len, val; + uint8_t copy[3][256], v8; + + len = (sizeof(*p) > 256) ? 256 : sizeof(*p); /* Try ONFI for unknown chip or LP */ chip->cmdfunc(mtd, NAND_CMD_READID, 0x20, -1); @@ -3170,11 +3172,36 @@ static int nand_flash_detect_onfi(struct mtd_info *mtd, struct nand_chip *chip, le16_to_cpu(p->crc)) { break; } + pr_err("CRC of parameter page %d is not valid\n", i); + for (j = 0; j < len; j++) + copy[i][j] = ((uint8_t *)p)[j]; } if (i == 3) { - pr_err("Could not find valid ONFI parameter page; aborting\n"); - return 0; + pr_err("Could not find valid ONFI parameter page\n"); + pr_info("Recover ONFI parameters with bit-wise majority\n"); + for (j = 0; j < len; j++) { + if (copy[0][j] == copy[1][j] || + copy[0][j] == copy[2][j]) { + ((uint8_t *)p)[j] = copy[0][j]; + } else if (copy[1][j] == copy[2][j]) { + ((uint8_t *)p)[j] = copy[1][j]; + } else { + ((uint8_t *)p)[j] = 0; + for (k = 0; k < 8; k++) { + v8 = (copy[0][j] >> k) & 0x1; + v8 += (copy[1][j] >> k) & 0x1; + v8 += (copy[2][j] >> k) & 0x1; + if (v8 > 1) + ((uint8_t *)p)[j] |= (1 << k); + } + } + } + if (onfi_crc16(ONFI_CRC_BASE, (uint8_t *)p, 254) != + le16_to_cpu(p->crc)) { + pr_err("ONFI parameter recovery failed, aborting\n"); + return 0; + } } /* Check version */ -- 1.7.9.5
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