Commit 0d17fc3e authored by Baruch Siach's avatar Baruch Siach Committed by Brian Norris
Browse files

mtd: mxc_nand: fix truncate of unaligned oob copying 



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: default avatarSascha Hauer <s.hauer@pengutronix.de>
Acked-by: default avatarUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: default avatarBaruch Siach <baruch@tkos.co.il>
Signed-off-by: default avatarBrian Norris <computersforpeace@gmail.com>
parent 7e7e4730

drivers/mtd/nand/mxc_nand.c

+36 −4
Original line number Diff line number Diff line
@@ -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);

	}

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