New subject: MX25L6445E erase and write failed!

20 Jun 2015


      On Wed, 4 Mar 2015 11:32:04 +0200
Urja Rannikko urjaman@gmail.com wrote:
...
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/b51f09e5f21bf14d492c7d006e0bdd869...
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 ...
Hi,
was this ever tested? I have a MX25L25635F which is yet unsupported due
to the larger address space etc. and I could test this eventually some
time in the future... but I would prefer to get support for this into
flashrom earlier than that (2016? :)
-- 
Kind regards/Mit freundlichen Grüßen, Stefan Tauner

Re: [flashrom] MX25L6445E erase and write failed!