[U-Boot] [PATCH] Fix CFI flash driver for 8-bit bus support

[Stefan Roese]

Hi Aaron,

On Tuesday 12 April 2011 10:33:05 Aaron Williams wrote:
> It looks like the other reset is not needed.

Good. Then please remove it from your patch and resend a new version labled 
"v2" [PATCH v2]. And please include the patch revision history as mentioned by 
Albert. See this link for details (especially "Sending updated patch 
versions"):

http://www.denx.de/wiki/view/U-Boot/Patches

> The delay is needed. Without
> it sometimes the reset would fail on some of our boards.

Understood.
 
> Here's what Garret Swalling at Spansion told me:
> 
> ...
> The CFI reset calls into two subroutines that resove to:
>         flash_write_cmd(info, 0, 0, AMD_CMD_RESET);
>         flash_write_cmd(info, 0, 0, FLASH_CMD_RESET);
> 
> According to the GL-N datasheet, even when there is no embedded operation
> ongoing, we need to allow at least 500ns for the reset to complete.  Maybe
> the extra command write and two additional function returns are allowing
> the flash enough time to complete the reset and respond to the next
> command. ---
> 
> While it seems to work without the delay at least on the one board I'm
> testing at the moment, I added it at at suggestion of Garret. I could try
> testing on all of the boards I'm supporting but I'd prefer not to (I'm
> supporting 15 different boards and 7 different processor families at the
> moment).

I see. I have no problems with your "cfi_flash driver - Add delay after reset 
command" patch. But please resend the 8/16 bit patch as mentioned above.

Thanks.

Cheers,
Stefan

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