From 3287f6d3858faee768a7c47515bd21914ad591a2 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Beno=C3=AEt=20Th=C3=A9baudeau?= Date: Fri, 16 Nov 2012 20:20:54 +0100 Subject: nand: Add torture feature MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This patch adds a NAND Flash torture feature, which is useful as a block stress test to determine if a block is still good and reliable (or should be marked as bad), e.g. after a write error. This code is ported from mtd-utils' lib/libmtd.c. Signed-off-by: Benoît Thébaudeau Cc: Scott Wood [scottwood@freescale.com: removed unnec. ifdef and unwrapped error strings] Signed-off-by: Scott Wood --- drivers/mtd/nand/nand_util.c | 122 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 122 insertions(+) (limited to 'drivers/mtd/nand') diff --git a/drivers/mtd/nand/nand_util.c b/drivers/mtd/nand/nand_util.c index 2855683..2ba0c5e 100644 --- a/drivers/mtd/nand/nand_util.c +++ b/drivers/mtd/nand/nand_util.c @@ -683,3 +683,125 @@ int nand_read_skip_bad(nand_info_t *nand, loff_t offset, size_t *length, return 0; } + +#ifdef CONFIG_CMD_NAND_TORTURE + +/** + * check_pattern: + * + * Check if buffer contains only a certain byte pattern. + * + * @param buf buffer to check + * @param patt the pattern to check + * @param size buffer size in bytes + * @return 1 if there are only patt bytes in buf + * 0 if something else was found + */ +static int check_pattern(const u_char *buf, u_char patt, int size) +{ + int i; + + for (i = 0; i < size; i++) + if (buf[i] != patt) + return 0; + return 1; +} + +/** + * nand_torture: + * + * Torture a block of NAND flash. + * This is useful to determine if a block that caused a write error is still + * good or should be marked as bad. + * + * @param nand NAND device + * @param offset offset in flash + * @return 0 if the block is still good + */ +int nand_torture(nand_info_t *nand, loff_t offset) +{ + u_char patterns[] = {0xa5, 0x5a, 0x00}; + struct erase_info instr = { + .mtd = nand, + .addr = offset, + .len = nand->erasesize, + }; + size_t retlen; + int err, ret = -1, i, patt_count; + u_char *buf; + + if ((offset & (nand->erasesize - 1)) != 0) { + puts("Attempt to torture a block at a non block-aligned offset\n"); + return -EINVAL; + } + + if (offset + nand->erasesize > nand->size) { + puts("Attempt to torture a block outside the flash area\n"); + return -EINVAL; + } + + patt_count = ARRAY_SIZE(patterns); + + buf = malloc(nand->erasesize); + if (buf == NULL) { + puts("Out of memory for erase block buffer\n"); + return -ENOMEM; + } + + for (i = 0; i < patt_count; i++) { + err = nand->erase(nand, &instr); + if (err) { + printf("%s: erase() failed for block at 0x%llx: %d\n", + nand->name, instr.addr, err); + goto out; + } + + /* Make sure the block contains only 0xff bytes */ + err = nand->read(nand, offset, nand->erasesize, &retlen, buf); + if ((err && err != -EUCLEAN) || retlen != nand->erasesize) { + printf("%s: read() failed for block at 0x%llx: %d\n", + nand->name, instr.addr, err); + goto out; + } + + err = check_pattern(buf, 0xff, nand->erasesize); + if (!err) { + printf("Erased block at 0x%llx, but a non-0xff byte was found\n", + offset); + ret = -EIO; + goto out; + } + + /* Write a pattern and check it */ + memset(buf, patterns[i], nand->erasesize); + err = nand->write(nand, offset, nand->erasesize, &retlen, buf); + if (err || retlen != nand->erasesize) { + printf("%s: write() failed for block at 0x%llx: %d\n", + nand->name, instr.addr, err); + goto out; + } + + err = nand->read(nand, offset, nand->erasesize, &retlen, buf); + if ((err && err != -EUCLEAN) || retlen != nand->erasesize) { + printf("%s: read() failed for block at 0x%llx: %d\n", + nand->name, instr.addr, err); + goto out; + } + + err = check_pattern(buf, patterns[i], nand->erasesize); + if (!err) { + printf("Pattern 0x%.2x checking failed for block at " + "0x%llx\n", patterns[i], offset); + ret = -EIO; + goto out; + } + } + + ret = 0; + +out: + free(buf); + return ret; +} + +#endif -- cgit v1.1