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

[Yuli Barcohen]

>>>>> 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.

-- 
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 Yuli Barcohen       | Phone +972-9-765-1788 |  Software Project Leader
 yuli at arabellasw.com | Fax   +972-9-765-7494 | Arabella Software, Israel
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