[flashrom] MX25L6445E erase and write failed!

[Urja Rannikko]

Hi,

> I've an idea. Maybe you've managed to switch the MX25L6445E into the
> "individual block protection mode" (read the datasheet page 30 - its
> an OTP, once done once its for good) and now it isnt actually
> erasing/writing anything at all (that 1M just happens to have
> succeeded previously) because flashrom currently doesnt know of the
> invidividual block unlock commands (or even the GBULK gang block
> unlock) and thinks everything is ok because the status register looks
> like unlocked.
>
> So maybe read the current contents into a file and modify a little bit
> in the erased area (eg. swap out the first 4k to random data*) and see
> if it writes. My theory is it wont.
>
> *here's example commands:
> flashrom <insert your parameters> -r current.bin
> dd if=/dev/urandom of=4krandom.bin bs=1024 count=4
> dd if=current.bin bs=1024 skip=4 of=current-4.bin
> cat 4krandom.bin current-4.bin > modified.bin
> flashrom <parameters> -w modified.bin
>
> Somebody'd need to write a patch to flashrom to use the RDSCUR command
> to see if WPSEL is set to see for sure. But support for this wouldnt
> hurt anyways. I'll see if i have time later in the evening to make a
> prototype/test patch for this...

I already had the datasheet open, so... here it is (in slightly crude form).
https://github.com/urjaman/flashrom/commit/b51f09e5f21bf14d492c7d006e0bdd869eee36b9
there's the commit if somebody wants to just web see.
To test, in the flashrom-serprog git tree you have:
git pull
git checkout mx25l6445e-debug
make
./flashrom ...



-- 
Urja Rannikko