Hej,
Has anyone used the at91_nand driver on the AT91SAM9260EK?
I get bad erase blocks on every block that contaions data (written to nand flash with SAM-BA). Seems like the read_oob (read out of bounds area) function is returning data from the in bounds area.
U-boot configs the nand flash to use hw ecc (syndrome) whereas the at91_nand seems to be setup to use soft ecc.
According to recent conversations on U-Boot mailing list U-boot can do a raw copy of a flash file system, but nothing more. (Correct me if I have misunderstood)
This means that if there are faulty pages in the NAND flash, you are dead. U-Boot needs to be able to map out JFFS2 or YAFFS(2) to be useful here. I.E. NAND flash is not functional as a boot memory yet.
If I understand correctly, you can read a JFFS2 fs in U-Boot
With the SAM9260, you can boot from an external dataflash card, containing Linux and a small file system. When this has booted, I think you can create a JFFS2 file system on the NAND flash. This should contain the Linux image as well.
U-Boot should then after reset, be able to read the linux from the JFFS2 file system and then boot.
I do not know if U-boot can fit into the NAND flash and I have not tested anything of above, but I think it should work. The programming time of the system will of course be significant, since you have to test the NAND flash for bad sectors..
If anyone has been down this path before, I would appreciate any pointers or assistance you can provide.
Michel
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Best Regards Ulf Samuelsson