[flashrom] Flashing ThinkPad X200

[potato]

Thanks for the help, the patch did work (the chip was detected), 
unfortunately  the system was not really reliable. The dumps were note 
matching and the chip was only detected on the first run of flashrom, 
after that it was needed to remove the USB device and insert-it again, 
otherwise the chip would not be find. Since there is no way to set the 
speed of the CH341A on flashrom right now, I will see if there is any 
way to "boost" the signal (or something like that) from the CH341A (and 
look on some other SPI programmers).

Potato

On 10-06-2016 14:57, Nico Huber wrote:
> Hi Potato,
>
> On 07.06.2016 18:59, potato wrote:
>> I know that the programmer works, since I was able to make goods dumps
>> of a MX25L8006 that was on a old router, but I was not able to detect a
>> MX25L6405D that was on my Thinkpad X200 (it could not even find a chip).
>> I know it is not a problem with the SOIC16 clip that I used since I was
>> able to use it on a rayer_spi device.
> The problem is not the flash chip itself but the circuitry surrounding
> it. Every device that you flash by ISP is a different story, especially
> when the device is not meant to be flashed by ISP. The X200 is one of
> those and particularly hard to flash. Presumably because of some capa-
> city on the CS line. So you need a programmer that can drive CS pretty
> strong, or work around by using a very low SPI clock or hack flashrom
> to assert CS earlier (that works for me using a FT2232H based program-
> mer). I've seen a Raspberry Pi 2 programming an X200 oob, supposedly it
> drives CS strong enough.
>
> Here's a clumsy patch for flashrom that might help:
> http://paste.flashrom.org/view.php?id=2802
> It adds dummy reads that might kind of pre-charge CS.
>
> Urja, do you know a way to assert CS earlier on a CH341A?
>
>> Sorry if I caused any problems, Potato
> No problems.
>
> Nico
>