diff options
| -rw-r--r-- | drivers/mtd/nand/mxc_nand.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c index 78e07cc7f..35e89a0f4 100644 --- a/drivers/mtd/nand/mxc_nand.c +++ b/drivers/mtd/nand/mxc_nand.c @@ -1371,7 +1371,18 @@ int board_nand_init(struct nand_chip *this) /* Blocks to be unlocked */ writew(0x0, &host->regs->nfc_unlockstart_blkaddr); - writew(0x4000, &host->regs->nfc_unlockend_blkaddr); + /* Originally (Freescale LTIB 2.6.21) 0x4000 was written to the + * unlockend_blkaddr, but the magic 0x4000 does not always work + * when writing more than some 32 megabytes (on 2k page nands) + * However 0xFFFF doesn't seem to have this kind + * of limitation (tried it back and forth several times). + * The linux kernel driver sets this to 0xFFFF for the v2 controller + * only, but probably this was not tested there for v1. + * The very same limitation seems to apply to this kernel driver. + * This might be NAND chip specific and the i.MX31 datasheet is + * extremely vague about the semantics of this register. + */ + writew(0xFFFF, &host->regs->nfc_unlockend_blkaddr); /* Unlock Block Command for given address range */ writew(0x4, &host->regs->nfc_wrprot); |