Hi Boris,
Boris Brezillon boris.brezillon@bootlin.com wrote on Wed, 11 Jul 2018 16:01:09 +0200:
On Wed, 11 Jul 2018 15:51:39 +0200 Miquel Raynal miquel.raynal@bootlin.com wrote:
- argc -= 3;
- argv += 3;
- /* Do the parsing */
- if (!strncmp(cmd, "read", 4) || !strncmp(cmd, "write", 5)) {
bool read, raw, woob;uint *waddr = NULL;u64 off, len;read = !strncmp(cmd, "read", 4);raw = strstr(cmd, ".raw");woob = strstr(cmd, ".oob");if (!read) {if (argc < 1)return CMD_RET_USAGE;waddr = map_sysmem(simple_strtoul(argv[0], NULL, 10),0);argc--;argv++;}off = argc > 0 ? simple_strtoul(argv[0], NULL, 10) : 0;len = argc > 1 ? simple_strtoul(argv[1], NULL, 10) :mtd->writesize + (woob ? mtd->oobsize : 0);if ((u32)off % mtd->writesize) {printf("Section not page-aligned (0x%x)\n",mtd->writesize);return -EINVAL;}if (woob && (len != (mtd->writesize + mtd->oobsize))) {printf("OOB operations are limited to single pages\n");return -EINVAL;}Is this a uboot limitation? I don't think you have such a limitation in Linux.
Kind of, only one single page write with OOB at a time is possible says a comment on mtd_oob_ops in mtd.h in Linux. Reads are actually not limited. But I really prefer to keep this limitation that simplifies _a lot_ the logic and is not really useful to a u-boot user I suppose.
It is useful when you write things in raw mode and the image you write contains OOB (which in turn contains pre-generated ECC bytes). I know we do such things on sunxi when writing the SPL.
:'(
Ok.
if ((off + len) >= mtd->size) {That doesn't work when reading the last page of the MTD device with woob = true. See how Linux handle that here [1]. BTW, why don't you let mtdcore.c do these checks for you (that's also true for unaligned accesses)?
Because the relevant patch (and its fix :) ) has not been backported yet.
And now I understand your voice in my ears "do it".
Hehe. So I guess I'll see this patch in your v2 :-).
Indeed ;)
Cheers, Miquèl