[U-Boot-Users] [PATCH] use CFI-Flash and board depended driver together
Tolunay Orkun
listmember at orkun.us
Wed Dec 6 17:57:10 CET 2006
Matvejchikov Ilya wrote:
> Hi all,
>
> While I try to examine cfi_flash.c file I have found that
> flash_detect_cfi() function used uninitialized value of
> info->cmd_reset:
>
> flash_get_size()
> {
> ....
> if (flash_detect_cfi(info)) {
> ....
> switch (info->vendor) {
> ....
> info->cmd_reset = x_CMD_RESET;
> ....
> }
> }
> }
>
> flash_detect_cfi(info)
> {
> ....
> flash_write_cmd (info, 0, 0, info->cmd_reset);
> ....
> }
>
> Am I right? Or may be - 'Is it true?' :)
Good obvervation... It is true but mostly harmless (if the garbage in
cmd_reset does not happen to be a valid command). The reset command is
issued if the attempt to put flash in CFI mode has failed. The line
could be removed and it would still work. When I designed my last patch
flash_read_jedec_ids(), I've specifically avoided the info->cmd_reset
for this reason.
Actually, AMD_CMD_RESET should be applicable to most Intel parts as well
per CFI spec documents. I think the Linux MTD driver choose to send the
Intel sequence followed by AMD sequence back to back during the probe.
BTW, Were you able to read my proposals to extend the CFI flash driver
to handle non-cfi chips. I've only received one comment so far. I am
waiting to get more comments before I go ahead with coding effort....
Best regards,
Tolunay
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