Adding support for a new chip

[Jean-Baptiste Skutnik]

Hello all,

I broke my motherboard and flashrom would help me save 300$. I need to
flash the BIOS chip and unfortunately, only the older version of the
chip seems to be supported, so I would need to patch support in.

The chip is the Winbond W25X40CL, which appears to be an upgrade over
the W25X40 that flashrom supports. However, when hooking it up, the
latter is detected and only the first 500K are available.

I would need some guidance on what to do next. Looking through the
gerrit I see the patches for new chip support add to flashchips.c and
include/flashchips.h.

Is there some documentation on what the fields represent in there so
that I am not plugging randomly ?

How does the process work when recognizing chips ? Would adding this
chip create a conflict with its predecessor ?

Thanks,

JB

[Anastasia Klimchuk]

Hello!

If you have datasheet for the chip you want to support, you can follow
the guidelines:
https://flashrom.org/contrib_howtos/how_to_add_new_chip.html

But this would also need you to have a dev environment (not the
machine with broken motherboard) and, an external programmer, is this
something that you have?
> How does the process work when recognizing chips ? Would adding this
> chip create a conflict with its predecessor ?

If there are multiple chips with the same model ID, flashrom will tell
you that after probing, and will tell you to pick which one you have
and re-run. There is also details on manpage
https://flashrom.org/classic_cli_manpage.html#options