[flashrom] SOIC8 test clip - cant write to BIOS SPI flash chip

[Denis 'GNUtoo' Carikli]

On Sat, 17 Oct 2015 12:57:54 +0200
Nico Huber <nico.h at gmx.de> wrote:
> 2. The write protection pin of your flash chip is asserted.
That's what I suspect too, but it could also be some other sort of
write protections. Some chip do support more flexible ways of write
protecting the chip, that's for instance used in the chromebook where,
if I understand correctly, only a region of the chip is protected (like
2MB/16MB for instance).

I should check the datasheet mentioned previously. I'll look briefly if
the issue is not resolved.

Robert, since the laptop is bricked anyway and that you already have
backups of the flash, you could try to erase the chip with "flashrom
--erase" and then dump the content of the chip again.
That way you could more easily see which zones have been erased, and
which haven't. Also please attach the log next time.

Also, I'm not used to all the issues related to powering the laptop on
or not, I never took the time to look that up.
Do you have a multimeter to investigate such issues? If so you could
check the voltages at the chip pins (to verify if any drop is
occurring), you could also check the value of pins like WP# (write
protect).

On Sat, 17 Oct 2015 12:57:54 +0200
Nico Huber <nico.h at gmx.de> wrote:
> I'd try with the AC adapter. In that case Vcc must _not_ be connected
> to your programmer. GND, OTOH, has to stay connected.
If that happens, could the EC be destroyed? or the laptop power system?
I've a laptop that doesn't lit its leds once a power supply is
connected to it. I broke it while messing with reflashing after trying
to test ME related stuff on it.

On Sat, 17 Oct 2015 12:57:54 +0200
Nico Huber <nico.h at gmx.de> wrote:
> > so that this Vcc pin would be powered by them, or it is forbidden
> > to do it while using SPI programmer in the same time?  
> Not forbidden. It's sometimes even encouraged because there are boards
> where the Vcc pin of the flash chip is directly connected to other
> chips, which would draw down the power from the programmer.
Robert, I think it can be detected by measuring the voltage at the pins
of the SPI programmer before and after plugging the clip.
Nico, Are there other common issues of the same kind with laptops?

Denis.
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