[flashrom] Re: cannot read/write thinkpad R500 chip AT25DF321

[Spenser Truex]

On 21/08/16 07:58PM, Alexander 'lynxis' Couzens wrote:
> Hi Spenser,
> > Issue is with flashrom though. Perhaps something about this chip in
> > particular? Any ideas moving forward?
>
> you should check the power supply and try to improve the signals of your
> SPI bus.
>
> power supply => either your power supply at all isn't sufficient or the
> spi chip draws too quick power that an additional capacitor (of
> the correct size) closer to the chip is required.
>
> signal => improve your cables, shielding, reduce EMI or
> desolder the chip and put it on a seperate board, etc.. Or reduce the
> spi speed, what you already did. Maybe use a different spi clip or
> solder cables on top of your spi chip instead of using a clip.
>
> in-system flashs are always special and depend on the PCB of your
> target board. Some boards aren't possible to flash at all. But you
> should be ok (there is a low chance of bricking).
>
> For sure there are bugs in flashrom. But usually it's power or signal
> integrity. If it's an bug within flashrom, I would also desolder the
> chip and solder it to a small debug board. So you could reduce other
> failures soures and test flashrom in a "known" environment.

Hello again,

I ordered a new R500, it happens to have the AT26DF321 chip also.
Flashrom -L says it doesn't support it. So I'm inclined to think support
for this chip doesn't exist, unless one of the other labels is actually
secretly the same chip.

So, how can I determine which solution out of those given above is needed
for this chip?

Thanks!
> Best,
> lynxis
> --
> Alexander Couzens
>
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