Re: [U-Boot-Users] [PATCH] AMD/Spansion write buffer support in cfi_flash.c

Alex BASTOS writes:
Yuli> 8-bit AMD/Spansion flashes are supported by current Yuli> driver. The patch would, in fact, break support for many such Yuli> flashes (29F016D, for example). Only in a special case of Yuli> 16-bit flash configured to work in 8-bit mode (29DL640D in Yuli> 8-bot mode, for example), such a change in command address can Yuli> be needed but IMHO this should be handled in run-time Yuli> according to CFI info.
Alex> Ummm, such a change is needed at least by S29GLxxxM flashes,
It's exactly the case which I mentioned: dual-mode (x8/x16) flash in 8-bit mode.
Alex> but I didn't know anything about 29F016D. Sorry about that. Alex> Any suggestion as info from to CFI which would select the Alex> correct command addresses?
There is a field in CFI information table which specifies flash interface (offset 0x50 in 8-bit mode, page 53 of S29GLxxxM data sheet). If the flash is x8/x16 and the driver detected that it's in 8-bit mode, this means that it's the above mentioned special case. I'd add a couple of fields to U-Boot's CFI flash structure to hold the addresses. Then simple shift would provide correct addresses.

Yuli,
There is a field in CFI information table which specifies flash interface (offset 0x50 in 8-bit mode, page 53 of S29GLxxxM data sheet). If the flash is x8/x16 and the driver detected that it's in 8-bit mode, this means that it's the above mentioned special case. I'd add a couple of fields to U-Boot's CFI flash structure to hold the addresses. Then simple shift would provide correct addresses.
It may be enough shifting the address each time it is needed (in fact, only two times).
Suggestions?
Alex BASTOS
participants (2)
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alebas@televes.com
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Yuli Barcohen