From 6e9411923b8f4c0e568cbae0f35b7ee4eb989914 Mon Sep 17 00:00:00 2001 From: Boris BREZILLON Date: Wed, 30 Dec 2015 20:32:03 +0100 Subject: [PATCH] mtd: nand: return consistent error codes in ecc.correct() implementations The error code returned by the ecc.correct() are not consistent over the all implementations. Document the expected behavior in include/linux/mtd/nand.h and fix offending implementations. [Brian: this looks like a bugfix for the ECC reporting in the bf5xx_nand driver, but we haven't seen any testing results for it] Signed-off-by: Boris Brezillon Tested-by: Franklin S Cooper Jr. Signed-off-by: Brian Norris --- drivers/mtd/nand/atmel_nand.c | 2 +- drivers/mtd/nand/bf5xx_nand.c | 20 ++++++++++++++------ drivers/mtd/nand/davinci_nand.c | 6 +++--- drivers/mtd/nand/jz4740_nand.c | 4 ++-- drivers/mtd/nand/mxc_nand.c | 4 ++-- drivers/mtd/nand/nand_bch.c | 2 +- drivers/mtd/nand/nand_ecc.c | 2 +- drivers/mtd/nand/omap2.c | 6 +++--- drivers/mtd/nand/r852.c | 4 ++-- include/linux/mtd/nand.h | 8 +++++++- include/linux/mtd/nand_bch.h | 2 +- 11 files changed, 37 insertions(+), 23 deletions(-) diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c index 18c4e14ec29f..b216bf521349 100644 --- a/drivers/mtd/nand/atmel_nand.c +++ b/drivers/mtd/nand/atmel_nand.c @@ -1445,7 +1445,7 @@ static int atmel_nand_correct(struct mtd_info *mtd, u_char *dat, * We can't correct so many errors */ dev_dbg(host->dev, "atmel_nand : multiple errors detected." " Unable to correct.\n"); - return -EIO; + return -EBADMSG; } /* if there's a single bit error : we can correct it */ diff --git a/drivers/mtd/nand/bf5xx_nand.c b/drivers/mtd/nand/bf5xx_nand.c index 9514e136542f..89d9414c5593 100644 --- a/drivers/mtd/nand/bf5xx_nand.c +++ b/drivers/mtd/nand/bf5xx_nand.c @@ -252,7 +252,7 @@ static int bf5xx_nand_correct_data_256(struct mtd_info *mtd, u_char *dat, */ if (hweight32(syndrome[0]) == 1) { dev_err(info->device, "ECC data was incorrect!\n"); - return 1; + return -EBADMSG; } syndrome[1] = (calced & 0x7FF) ^ (stored & 0x7FF); @@ -285,7 +285,7 @@ static int bf5xx_nand_correct_data_256(struct mtd_info *mtd, u_char *dat, data = data ^ (0x1 << failing_bit); *(dat + failing_byte) = data; - return 0; + return 1; } /* @@ -298,26 +298,34 @@ static int bf5xx_nand_correct_data_256(struct mtd_info *mtd, u_char *dat, dev_err(info->device, "Please discard data, mark bad block\n"); - return 1; + return -EBADMSG; } static int bf5xx_nand_correct_data(struct mtd_info *mtd, u_char *dat, u_char *read_ecc, u_char *calc_ecc) { struct nand_chip *chip = mtd_to_nand(mtd); - int ret; + int ret, bitflips = 0; ret = bf5xx_nand_correct_data_256(mtd, dat, read_ecc, calc_ecc); + if (ret < 0) + return ret; + + bitflips = ret; /* If ecc size is 512, correct second 256 bytes */ if (chip->ecc.size == 512) { dat += 256; read_ecc += 3; calc_ecc += 3; - ret |= bf5xx_nand_correct_data_256(mtd, dat, read_ecc, calc_ecc); + ret = bf5xx_nand_correct_data_256(mtd, dat, read_ecc, calc_ecc); + if (ret < 0) + return ret; + + bitflips += ret; } - return ret; + return bitflips; } static void bf5xx_nand_enable_hwecc(struct mtd_info *mtd, int mode) diff --git a/drivers/mtd/nand/davinci_nand.c b/drivers/mtd/nand/davinci_nand.c index 3b49fe86625d..ddb73c331936 100644 --- a/drivers/mtd/nand/davinci_nand.c +++ b/drivers/mtd/nand/davinci_nand.c @@ -207,7 +207,7 @@ static int nand_davinci_correct_1bit(struct mtd_info *mtd, u_char *dat, dat[diff >> (12 + 3)] ^= BIT((diff >> 12) & 7); return 1; } else { - return -1; + return -EBADMSG; } } else if (!(diff & (diff - 1))) { /* Single bit ECC error in the ECC itself, @@ -215,7 +215,7 @@ static int nand_davinci_correct_1bit(struct mtd_info *mtd, u_char *dat, return 1; } else { /* Uncorrectable error */ - return -1; + return -EBADMSG; } } @@ -391,7 +391,7 @@ compare: return 0; case 1: /* five or more errors detected */ davinci_nand_readl(info, NAND_ERR_ERRVAL1_OFFSET); - return -EIO; + return -EBADMSG; case 2: /* error addresses computed */ case 3: num_errors = 1 + ((fsr >> 16) & 0x03); diff --git a/drivers/mtd/nand/jz4740_nand.c b/drivers/mtd/nand/jz4740_nand.c index a2363d33cecc..adccae3da120 100644 --- a/drivers/mtd/nand/jz4740_nand.c +++ b/drivers/mtd/nand/jz4740_nand.c @@ -254,7 +254,7 @@ static int jz_nand_correct_ecc_rs(struct mtd_info *mtd, uint8_t *dat, } while (!(status & JZ_NAND_STATUS_DEC_FINISH) && --timeout); if (timeout == 0) - return -1; + return -ETIMEDOUT; reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL); reg &= ~JZ_NAND_ECC_CTRL_ENABLE; @@ -262,7 +262,7 @@ static int jz_nand_correct_ecc_rs(struct mtd_info *mtd, uint8_t *dat, if (status & JZ_NAND_STATUS_ERROR) { if (status & JZ_NAND_STATUS_UNCOR_ERROR) - return -1; + return -EBADMSG; error_count = (status & JZ_NAND_STATUS_ERR_COUNT) >> 29; diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c index 95400992c3e9..66e56bb22c0f 100644 --- a/drivers/mtd/nand/mxc_nand.c +++ b/drivers/mtd/nand/mxc_nand.c @@ -674,7 +674,7 @@ static int mxc_nand_correct_data_v1(struct mtd_info *mtd, u_char *dat, if (((ecc_status & 0x3) == 2) || ((ecc_status >> 2) == 2)) { pr_debug("MXC_NAND: HWECC uncorrectable 2-bit ECC error\n"); - return -1; + return -EBADMSG; } return 0; @@ -701,7 +701,7 @@ static int mxc_nand_correct_data_v2_v3(struct mtd_info *mtd, u_char *dat, err = ecc_stat & ecc_bit_mask; if (err > err_limit) { printk(KERN_WARNING "UnCorrectable RS-ECC Error\n"); - return -1; + return -EBADMSG; } else { ret += err; } diff --git a/drivers/mtd/nand/nand_bch.c b/drivers/mtd/nand/nand_bch.c index e5758d885943..a87c1b628dfc 100644 --- a/drivers/mtd/nand/nand_bch.c +++ b/drivers/mtd/nand/nand_bch.c @@ -98,7 +98,7 @@ int nand_bch_correct_data(struct mtd_info *mtd, unsigned char *buf, } } else if (count < 0) { printk(KERN_ERR "ecc unrecoverable error\n"); - count = -1; + count = -EBADMSG; } return count; } diff --git a/drivers/mtd/nand/nand_ecc.c b/drivers/mtd/nand/nand_ecc.c index e6129851bfd8..d1770b066396 100644 --- a/drivers/mtd/nand/nand_ecc.c +++ b/drivers/mtd/nand/nand_ecc.c @@ -507,7 +507,7 @@ int __nand_correct_data(unsigned char *buf, return 1; /* error in ECC data; no action needed */ pr_err("%s: uncorrectable ECC error\n", __func__); - return -1; + return -EBADMSG; } EXPORT_SYMBOL(__nand_correct_data); diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c index e9cbbc63c566..c553f78ab83f 100644 --- a/drivers/mtd/nand/omap2.c +++ b/drivers/mtd/nand/omap2.c @@ -826,12 +826,12 @@ static int omap_compare_ecc(u8 *ecc_data1, /* read from NAND memory */ case 1: /* Uncorrectable error */ pr_debug("ECC UNCORRECTED_ERROR 1\n"); - return -1; + return -EBADMSG; case 11: /* UN-Correctable error */ pr_debug("ECC UNCORRECTED_ERROR B\n"); - return -1; + return -EBADMSG; case 12: /* Correctable error */ @@ -861,7 +861,7 @@ static int omap_compare_ecc(u8 *ecc_data1, /* read from NAND memory */ return 0; } pr_debug("UNCORRECTED_ERROR default\n"); - return -1; + return -EBADMSG; } } diff --git a/drivers/mtd/nand/r852.c b/drivers/mtd/nand/r852.c index cb0bf09214d5..5b15f2faee38 100644 --- a/drivers/mtd/nand/r852.c +++ b/drivers/mtd/nand/r852.c @@ -477,7 +477,7 @@ static int r852_ecc_correct(struct mtd_info *mtd, uint8_t *dat, if (dev->dma_error) { dev->dma_error = 0; - return -1; + return -EIO; } r852_write_reg(dev, R852_CTL, dev->ctlreg | R852_CTL_ECC_ACCESS); @@ -491,7 +491,7 @@ static int r852_ecc_correct(struct mtd_info *mtd, uint8_t *dat, /* ecc uncorrectable error */ if (ecc_status & R852_ECC_FAIL) { dbg("ecc: unrecoverable error, in half %d", i); - error = -1; + error = -EBADMSG; goto exit; } diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h index 3e92be1d2d43..518958115182 100644 --- a/include/linux/mtd/nand.h +++ b/include/linux/mtd/nand.h @@ -456,7 +456,13 @@ struct nand_hw_control { * @hwctl: function to control hardware ECC generator. Must only * be provided if an hardware ECC is available * @calculate: function for ECC calculation or readback from ECC hardware - * @correct: function for ECC correction, matching to ECC generator (sw/hw) + * @correct: function for ECC correction, matching to ECC generator (sw/hw). + * Should return a positive number representing the number of + * corrected bitflips, -EBADMSG if the number of bitflips exceed + * ECC strength, or any other error code if the error is not + * directly related to correction. + * If -EBADMSG is returned the input buffers should be left + * untouched. * @read_page_raw: function to read a raw page without ECC. This function * should hide the specific layout used by the ECC * controller and always return contiguous in-band and diff --git a/include/linux/mtd/nand_bch.h b/include/linux/mtd/nand_bch.h index 74acf5367556..fb0bc3420a10 100644 --- a/include/linux/mtd/nand_bch.h +++ b/include/linux/mtd/nand_bch.h @@ -55,7 +55,7 @@ static inline int nand_bch_correct_data(struct mtd_info *mtd, unsigned char *buf, unsigned char *read_ecc, unsigned char *calc_ecc) { - return -1; + return -ENOTSUPP; } static inline struct nand_bch_control * -- 2.30.2