Apologies if this is a double -post - I didn't get it back in my feed from the mailing list.... maybe it is awaiting approval or something. But I'm off on holiday, and I'd really like it to be "out there" -----------------------------------------------------------------
I thought the whole point of using this linux and u-boot stuff was that whatever you did, someone else had done it first and you just had to copy them.
Well I've been caught out Smile
I want to ditch using the uSD card at all on our AVR32 board , and use NAND where we have been using uSD.
I have a Linux disk working out of NAND - quite easy as Linux pretty much knew how, once you told it you had a chip.
But the u-boot seems to have no clue about NAND on the AVR32 - it doesn't set up the hardware to get to it at all, and there's no code set up in the target board header and code files for any AVR32-based board, as far as I can see!!!
I have found some stuff in support for other Atmel devices, which seems relevant. Plus of course the Linux sources.
I'm totally in the dark about what u-boot can or should do with ecc .....
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So far I've worked out that I've got to
1. in cpu.c add set up MODE3, CYCLE3, SETUP3, PULSE3 registers for cs3 timing.
2. in <target>.c/board_early_init_f add hmatrix_slave_write call to enable nand in ebi
3. in <target>.c/board_early_init_f set up chip select(s) and busy(s) in the GPIO setup to point the right way, and initially turn everything off
4 in <target>.h
#undef CONFIG_NAND_LEGACY
#define CONFIG_CMD_NAND #define CONFIG_JFFS2_NAND #define CFG_MAX_NAND_DEVICE #define NAND_MAX_CHIPS #define CFG_NAND_BASE 0x0c000000
I'm still pretty woolly about these though
CONFIG_MTD_NAND_VERIFY_WRITE CONFIG_MTD_PARTITIONS
5. create a file called nand.c in the same directory as my <target>.c - I've based mine on the one for the at91sam9261ek. This needs to implement
board_nand_init which must set up service routines cmd_ctrl to alter ALE,CLE etc dev_ready to read the "chip ready" status chip_delay - no idea!
so far I've no clue how this file gets included in the make of u-boot.
Any and all advice welcome - especially if someone HAS got there first.
TVM
David