Re: [Libreboot] flashrom fails with BIOS chip on ThinkPad T400

[ng0]

Thomas Umbach <address@hidden> writes:

> Hello Johannes,
>
> On Mon, 25 Apr 2016 17:42:40 +0200
> Johannes Merkert <address@hidden> wrote:
>
>> -----BEGIN PGP SIGNED MESSAGE-----
>> Hash: SHA256
>> 
>> Hi,
>> 
>> my Name is Johannes Merkert and I am an author for the german computer
>> magazine c't (ct.de). I tried to install Libreboot on a ThinkPad T400
>> following the guide on libreboot.org
>> (https://libreboot.org/docs/install/t400_external.html).
>> 
>> When I tried to test flashrom with the BIOS chip I got the following
>> error:
>> 
>> address@hidden:~# ./flashrom -p
>> linux_spi:dev=/dev/spidev1.0,spispeed=5 12
>> flashrom v0.9.8-unknown on Linux 3.8.13-bone79 (armv7l)
>> flashrom is free software, get the source code at
>> http://www.flashrom.or g
>> 
>> Calibrating delay loop... OK.
>> Found Generic flash chip "unknown SPI chip (RDID)" (0 kB, SPI) on
>> linux_spi.
>> ===
>> This flash part has status NOT WORKING for operations: PROBE READ
>> ERASE WRITE
>> The test status of this chip may have been updated in the latest
>> development
>> version of flashrom. If you are running the latest development
>> version, please email a report to address@hidden if any of the
>> above operations
>> work correctly for you with this flash chip. Please include the
>> flashrom log
>> file for all operations you tested (see the man page for details), and
>> mention
>> which mainboard or programmer you tested in the subject line.
>> Thanks for your help!
>> No operations were specified.
>> 
>> Does this mean my T400 uses another flash chip and I can not upgrade
>> it to libreboot?
>
> Good news: Most likely not.
>
> This usually happens due to a bad contact, bad or too long cables.
> If you go by the manual, you can't do it wrong. Sometimes it'll work
> when you're just about to give up - don't give up! =)
>
> Check for
>  * max cable length 10cm or so for all cables (the cables are usually
>    unshielded)

It worked for me so far with BeagleBone Black + 25cm female
cables + male adapters from Conrad Electronics store + Pomona
clips.

>  * power: use an external pdu for all pins on the clip and the BBB that
>    need Vcc (I'm using a lab pdu which works well, but any pdu will
>    do)
>  * check if you've made the right connections (the flashing manual is
>    good and doesn't leave anything out at all, but it can be confusing
>    if you don't have experience)
>  * check if the clip has a good contact
>  * try over and over again, perhaps wiggle the cables in between (last
>    time I flashed I needed 20 or so attempts)
>
> Note: The X200 is far more easy to flash because you only need to
> lift the palm rest and have access to the chip immediately. You'd have
> the same problems flashing if you have a bad setup though. 
>
> Good luck.
>
>> 
>> Faithfully,
>>   Johannes Merkert

I had a reading problem with the t400 at first too, but it was
resolved when I looked at the chip manual/specs, it was resolved
like this for me, using the BBB's P9 with the SOIC 300-MIL:
Connect VCC, CS, MISO, MOSI, GND, CLK.
Sometimes miso and mosi are switched.
In case of bbb rev c, d0 and d1 on P9 are MOSI/MISO.

For me personally I also had forgotten to connect power (3V pin
on the P9 of BBB) from BBB to the chip, without power no
reading/writing.
The BeagleBone Powersource (its own power adapter, not an
external one) worked for me in my case.

I'd recommend to get the chips manual and compare connections, I
only know for T400 with SOIC 300-MIL

-- 
♥Ⓐ ng0