From 0d17fc3e998357469700e0782d253c31a6997505 Mon Sep 17 00:00:00 2001 From: Baruch Siach Date: Wed, 13 May 2015 11:17:38 +0300 Subject: [PATCH] mtd: mxc_nand: fix truncate of unaligned oob copying MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Copy to/from oob io area might not be aligned to 4 bytes. When 8 bit ECC is used, the buffer size is 26. Add memcpy16_{to,from}io, and use them to avoid truncating the buffer. Prefer memcpy32_{to,from}io when the buffer is properly aligned for better performance. Reviewed-by: Sascha Hauer Acked-by: Uwe Kleine-König Signed-off-by: Baruch Siach Signed-off-by: Brian Norris --- drivers/mtd/nand/mxc_nand.c | 40 +++++++++++++++++++++++++++++++++---- 1 file changed, 36 insertions(+), 4 deletions(-) diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c index ceeb61cad7d4..260d77d5cc21 100644 --- a/drivers/mtd/nand/mxc_nand.c +++ b/drivers/mtd/nand/mxc_nand.c @@ -281,12 +281,44 @@ static void memcpy32_fromio(void *trg, const void __iomem *src, size_t size) *t++ = __raw_readl(s++); } +static void memcpy16_fromio(void *trg, const void __iomem *src, size_t size) +{ + int i; + u16 *t = trg; + const __iomem u16 *s = src; + + /* We assume that src (IO) is always 32bit aligned */ + if (PTR_ALIGN(trg, 4) == trg && IS_ALIGNED(size, 4)) { + memcpy32_fromio(trg, src, size); + return; + } + + for (i = 0; i < (size >> 1); i++) + *t++ = __raw_readw(s++); +} + static inline void memcpy32_toio(void __iomem *trg, const void *src, int size) { /* __iowrite32_copy use 32bit size values so divide by 4 */ __iowrite32_copy(trg, src, size / 4); } +static void memcpy16_toio(void __iomem *trg, const void *src, int size) +{ + int i; + __iomem u16 *t = trg; + const u16 *s = src; + + /* We assume that trg (IO) is always 32bit aligned */ + if (PTR_ALIGN(src, 4) == src && IS_ALIGNED(size, 4)) { + memcpy32_toio(trg, src, size); + return; + } + + for (i = 0; i < (size >> 1); i++) + __raw_writew(*s++, t++); +} + static int check_int_v3(struct mxc_nand_host *host) { uint32_t tmp; @@ -832,22 +864,22 @@ static void copy_spare(struct mtd_info *mtd, bool bfrom) if (bfrom) { for (i = 0; i < num_chunks - 1; i++) - memcpy32_fromio(d + i * oob_chunk_size, + memcpy16_fromio(d + i * oob_chunk_size, s + i * sparebuf_size, oob_chunk_size); /* the last chunk */ - memcpy32_fromio(d + i * oob_chunk_size, + memcpy16_fromio(d + i * oob_chunk_size, s + i * sparebuf_size, host->used_oobsize - i * oob_chunk_size); } else { for (i = 0; i < num_chunks - 1; i++) - memcpy32_toio(&s[i * sparebuf_size], + memcpy16_toio(&s[i * sparebuf_size], &d[i * oob_chunk_size], oob_chunk_size); /* the last chunk */ - memcpy32_toio(&s[oob_chunk_size * sparebuf_size], + memcpy16_toio(&s[oob_chunk_size * sparebuf_size], &d[i * oob_chunk_size], host->used_oobsize - i * oob_chunk_size); } -- 2.20.1