[U-Boot-Users] NAND booting on S3C2410 and NS9750

[U-Boot-Users] NAND booting on S3C2410 and NS9750

[Markus Pietrek]

Hi folks,

we'd like to use U-Boot (1.0) on our S3C2410 and NS9750 ARM920 platforms, but 
will be using NAND flash only. If i'm informed correctly NAND Booting is not 
yet supported in U-Boot. Therefore I would have to add this myself and want 
to share my ideas before.

o The relocation  in cpu/arm920t/start.S (after relocate:) needs to be
  replaced by generic code reading the bootloader blocks from NAND and put
  them in RAM. The NAND_read_block functions are processor/board specific and
  need to be placed somewhere in board/smdk2410/ etc.
o As the S3C2410 reads only the first 4kB of the NAND itself, this code must
   be placed altogether in the first 4kB
o The linker script needs to be modified to put _start, _armboot_start, 
  _armboot_end and _TEXT_BASE in the first 4kB, too, so u-boot can be placed
   correctly at the end of the RAM 
o  for NAND flashes only, the relocation code may need only the number of
   blocks to read or may determine that itself by _armboot_end. But using a
   "block list" programmed into, U-Boot could be used on smart media cards
   with part of the boot-loader in the filesystem, too.

Any comments?

Best regards,

-- 
Markus Pietrek
FS Forth-Systeme GmbH
Phone: +49 (7667) 908 145,  FAX +49 (7667) 908 221