> Anything is possible.
>
> Most common would probably be the default layouts defined in
> drivers/mtd/nand/nand_base.c
>
> The yaffs tags will be stored in the area defined in .oobfree
>
> eg.
> static struct nand_ecclayout nand_oob_64 = {
> .eccbytes = 24,
> .eccpos = {
> 40, 41, 42, 43, 44, 45, 46, 47,
> 48, 49, 50, 51, 52, 53, 54, 55,
> 56, 57, 58, 59, 60, 61, 62, 63},
> .oobfree = {
> {.offset = 2,
> .length = 38} }
> };
>
> Here
>
> bytes 0,1 are the bad block marker (should be 0xff)
> bytes 2..39 contain the yaffs tags a struct yaffs_packed_tags2
> bytes 40..63 contain ECC bytes.
I think it is unlikely that is the layout that Eugene has though, as the
OOB hex dumps he sent:
19 91 65 5A 15 1C 81 88 9D E2 24 79 C5 84 F5 43
F3 D9 11 4C AF 1F AE 8A 9E 3E FA CD 51 0A 5F 1D
00 00 F2 01 00 00 04 00 00 00 00 08 00 00 DB 2C
E8 F1 16 5F 5C DB 19 32 00 00 00 00 00 00 00 00
54 0C 1A 2F 62 DA 6B D1 D6 AC A8 CF 56 CF FA 43
09 9F 79 FF A8 CF 56 CF FA 43 09 9F 79 FF 5F 1D
00 00 89 01 00 10 0E 01 00 80 88 E6 03 00 D4 B9
63 32 71 3C 16 50 60 88 00 00 00 00 00 00 00 00
0F C8 31 64 71 3C 71 79 3F 72 A8 CF 56 CF FA 43
09 9F 79 FF A8 CF 56 CF FA 43 09 9F 79 FF 5F 1D
00 00 8A 01 00 30 09 01 00 80 00 00 00 00 3A DD
34 66 99 F3 2A DA 2E 48 00 00 00 00 00 00 00 00
Would all be tagged as bad according to that layout. I suspect that
something else is going on here, because yaffs only uses around 12 bytes
of OOB doesn't it, along with the bad block marker, and ecc, normally
you'd expect to see a lot more FF bytes in there.
Regards,
Andre
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