From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <1472470806.11041.5.camel@mtkswgap22> Subject: [PATCH v2 1/2] mtd: nand: fix generating over-boundary ECC data when writing. From: RogerCC.Lin To: Boris Brezillon CC: , , , , , , , , , , Jorge Ramirez-Ortiz Date: Mon, 29 Aug 2016 19:40:06 +0800 In-Reply-To: <20160829101006.2b200e0a@bbrezillon> References: <1472443093.27061.4.camel@mtkswgap22> <20160829101006.2b200e0a@bbrezillon> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit MIME-Version: 1.0 List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , When mtk_ecc_encode() is writing the ECC parity data to the OOB region,because each register is 4 bytes in length,but the len's unit is in bytes,the operation in the for loop will cross the ECC's boundary. Signed-off-by: RogerCC Lin --- drivers/mtd/nand/mtk_ecc.c | 12 ++++++++---- 1 files changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/mtd/nand/mtk_ecc.c b/drivers/mtd/nand/mtk_ecc.c index 25a4fbd..495538e 100644 --- a/drivers/mtd/nand/mtk_ecc.c +++ b/drivers/mtd/nand/mtk_ecc.c @@ -366,7 +366,8 @@ int mtk_ecc_encode(struct mtk_ecc *ecc, struct mtk_ecc_config *config, u8 *data, u32 bytes) { dma_addr_t addr; - u32 *p, len, i; + u8 *p; + u32 len, i, val; int ret = 0; addr = dma_map_single(ecc->dev, data, bytes, DMA_TO_DEVICE); @@ -392,11 +393,14 @@ int mtk_ecc_encode(struct mtk_ecc *ecc, struct mtk_ecc_config *config, /* Program ECC bytes to OOB: per sector oob = FDM + ECC + SPARE */ len = (config->strength * ECC_PARITY_BITS + 7) >> 3; - p = (u32 *)(data + bytes); + p = data + bytes; /* write the parity bytes generated by the ECC back to the OOB region */ - for (i = 0; i < len; i++) - p[i] = readl(ecc->regs + ECC_ENCPAR(i)); + for (i = 0; i < len; i++) { + if ((i % 4) == 0) + val = readl(ecc->regs + ECC_ENCPAR(i >> 2)); + p[i] = (val >> ((i % 4) * 8)) & 0xff; + } timeout: dma_unmap_single(ecc->dev, addr, bytes, DMA_TO_DEVICE); -- 1.7.0.4