flashrom success with GD25Q20(B)

[Gilles Auréjac]

hi

Just to let you know that flashrom v0.9.6.1-r1704did succesfully read and wrote to a GD25Q20(B° eeprom with a buspirate v.3.b hardware.

Here is the flashrom -Vw output.

best regards

gilles

[Stefan Tauner]

On Mon, 5 Jan 2015 14:46:26 +0100
Gilles Auréjac  wrote:
> Reading old flash chip contents... done.
> Erasing and writing flash chip... Trying erase function 0... 0x000000-0x000fff:S, 0x001000-0x001fff:S, 0x002000-0x002fff:S, 0x003000-0x003fff:S, 0x004000-0x004fff:S, 0x005000-0x005fff:S, 0x006000-0x006fff:S, 0x007000-0x007fff:S, 0x008000-0x008fff:S, 0x009000-0x009fff:S, 0x00a000-0x00afff:S, 0x00b000-0x00bfff:S, 0x00c000-0x00cfff:S, 0x00d000-0x00dfff:S, 0x00e000-0x00efff:S, 0x00f000-0x00ffff:S, 0x010000-0x010fff:S, 0x011000-0x011fff:S, 0x012000-0x012fff:S, 0x013000-0x013fff:S, 0x014000-0x014fff:S, 0x015000-0x015fff:S, 0x016000-0x016fff:S, 0x017000-0x017fff:S, 0x018000-0x018fff:S, 0x019000-0x019fff:S, 0x01a000-0x01afff:S, 0x01b000-0x01bfff:S, 0x01c000-0x01cfff:S, 0x01d000-0x01dfff:S, 0x01e000-0x01efff:S, 0x01f000-0x01ffff:S, 0x020000-0x020fff:S, 0x021000-0x021fff:S, 0x022000-0x022fff:S, 0x023000-0x023fff:S, 0x024000-0x024fff:S, 0x025000-0x025fff:S, 0x026000-0x026fff:S, 0x027000-0x027fff:S, 0x028000-0x028fff:S, 0x029000-0x029fff:S, 0x02a000-0x02afff:S, 0x02b000-0x02bfff:S, 0x02c000-0x02cfff:S, 0x02d000-0x02dfff:S, 0x02e000-0x02efff:S, 0x02f000-0x02ffff:S, 0x030000-0x030fff:S, 0x031000-0x031fff:S, 0x032000-0x032fff:S, 0x033000-0x033fff:S, 0x034000-0x034fff:S, 0x035000-0x035fff:S, 0x036000-0x036fff:S, 0x037000-0x037fff:S, 0x038000-0x038fff:S, 0x039000-0x039fff:S, 0x03a000-0x03afff:S, 0x03b000-0x03bfff:S, 0x03c000-0x03cfff:S, 0x03d000-0x03dfff:S, 0x03e000-0x03efff:S, 0x03f000-0x03ffff:S
>
> Warning: Chip content is identical to the requested image.
> Erase/write done.

Hello Gilles,

the log you sent does not really indicate a successful write as the
warning indicates... flashrom has skipped all blocks. I guess you just
ran the write process with the same file twice and that's why. Can you
please confirm that the chip was indeed written at some time before
you created the log above?

[Gilles Aurejac]

Hello Stefan,

you're right I did wrote to the flash ship twice (and forgot the -V option the first time).
I'm confident that the write operation worked : I first have read and save, then updated this chip (2nd bios chip of a gtx 770 nvidia card) succesfully with flashrom and compared with an hexadecimal the 2 dumps which reported the attempted differences.

If you wish I can ran the write operation again and send you the result.

Also I did not have the same success with the 1rst bios chip which is not recognized (0Kb) by flashrom, and neither by nvflash under windows (nvflash says : unknown eeprom - BF,008D : this is a SST chip)
This is a 2Mbits spi eeprom with a sot-23 package.

regards

gilles
> Le 5 janv. 2015 à 22:02, Stefan Tauner  a écrit :
>
> On Mon, 5 Jan 2015 14:46:26 +0100
> Gilles Auréjac  wrote:
> > Reading old flash chip contents... done.
> > Erasing and writing flash chip... Trying erase function 0... 0x000000-0x000fff:S, 0x001000-0x001fff:S, 0x002000-0x002fff:S, 0x003000-0x003fff:S, 0x004000-0x004fff:S, 0x005000-0x005fff:S, 0x006000-0x006fff:S, 0x007000-0x007fff:S, 0x008000-0x008fff:S, 0x009000-0x009fff:S, 0x00a000-0x00afff:S, 0x00b000-0x00bfff:S, 0x00c000-0x00cfff:S, 0x00d000-0x00dfff:S, 0x00e000-0x00efff:S, 0x00f000-0x00ffff:S, 0x010000-0x010fff:S, 0x011000-0x011fff:S, 0x012000-0x012fff:S, 0x013000-0x013fff:S, 0x014000-0x014fff:S, 0x015000-0x015fff:S, 0x016000-0x016fff:S, 0x017000-0x017fff:S, 0x018000-0x018fff:S, 0x019000-0x019fff:S, 0x01a000-0x01afff:S, 0x01b000-0x01bfff:S, 0x01c000-0x01cfff:S, 0x01d000-0x01dfff:S, 0x01e000-0x01efff:S, 0x01f000-0x01ffff:S, 0x020000-0x020fff:S, 0x021000-0x021fff:S, 0x022000-0x022fff:S, 0x023000-0x023fff:S, 0x024000-0x024fff:S, 0x025000-0x025fff:S, 0x026000-0x026fff:S, 0x027000-0x027fff:S, 0x028000-0x028fff:S, 0x029000-0x029fff:S, 0x02a000-0x02afff:S, 0x02b000-0x02bfff:S, 0x02c000-0x02cfff:S, 0x02d000-0x02dfff:S, 0x02e000-0x02efff:S, 0x02f000-0x02ffff:S, 0x030000-0x030fff:S, 0x031000-0x031fff:S, 0x032000-0x032fff:S, 0x033000-0x033fff:S, 0x034000-0x034fff:S, 0x035000-0x035fff:S, 0x036000-0x036fff:S, 0x037000-0x037fff:S, 0x038000-0x038fff:S, 0x039000-0x039fff:S, 0x03a000-0x03afff:S, 0x03b000-0x03bfff:S, 0x03c000-0x03cfff:S, 0x03d000-0x03dfff:S, 0x03e000-0x03efff:S, 0x03f000-0x03ffff:S
> >
> > Warning: Chip content is identical to the requested image.
> > Erase/write done.
>
> Hello Gilles,
>
> the log you sent does not really indicate a successful write as the
> warning indicates... flashrom has skipped all blocks. I guess you just
> ran the write process with the same file twice and that's why. Can you
> please confirm that the chip was indeed written at some time before
> you created the log above?

[Stefan Tauner]

On Tue, 6 Jan 2015 02:54:31 +0100
Gilles Aurejac  wrote:
> you're right I did wrote to the flash ship twice (and forgot the -V option the first time).
> I'm confident that the write operation worked : I first have read and save, then updated this chip (2nd bios chip of a gtx 770 nvidia card) succesfully with flashrom and compared with an hexadecimal the 2 dumps which reported the attempted differences.
>
> If you wish I can ran the write operation again and send you the result.

Hi,

no need, I just wanted to make sure.
I have marked the flash chip as fully tested and will commit that later
together with other small changes.
> Also I did not have the same success with the 1rst bios chip which is not recognized (0Kb) by flashrom, and neither by nvflash under windows (nvflash says : unknown eeprom - BF,008D : this is a SST chip)
> This is a 2Mbits spi eeprom with a sot-23 package.

sot-23 would be pretty spectacular... because that has only 3 pins ;)
I believe you mean SOIC-8 instead.

SPI flashes can use a few different ID methods which often share (parts
of) ID bytes. 0xBF is indeed the SST vendor ID... and 0x8d is even (the
main) part of a known device: the SST25VF040B. But it should be
detected ok with flashrom. Can you please send us the log produced with:
flashrom -p buspirate_spi:dev=COM5 -VVV -o SST25VF040B_probe_spew.log
Maybe I can spot what/if something is wrong.

The top marking of the chip would also help very much in verifying if
it is a SST25VF040B or something else.

[Gilles Auréjac]

Hi Stefan,

I understand that it looks strange, but yes it is a small 6-pin package, with I maybe wrongle identified as a 6-pin sot23 (or sot23-6) package.
I'm not sure about the pinouts, though (I easily found vdd and vcc, bot on other trace are hard to follow on the board of the graphic card)
Whith a magnifier I only manage to read the two letters YU on the package...

What is strange is with those packages I only found datasheets of smaller eeprom (1k, 2k, but not 1 or 2Mbits which is the attempted size regarding the size of bios of those products)

I'll run the command and send you photos later this day

regards

gilles

Le 6 janv. 2015 à 11:10, Stefan Tauner  a écrit :
> On Tue, 6 Jan 2015 02:54:31 +0100
> Gilles Aurejac  wrote:
> > you're right I did wrote to the flash ship twice (and forgot the -V option the first time).
> > I'm confident that the write operation worked : I first have read and save, then updated this chip (2nd bios chip of a gtx 770 nvidia card) succesfully with flashrom and compared with an hexadecimal the 2 dumps which reported the attempted differences.
> >
> > If you wish I can ran the write operation again and send you the result.
>
> Hi,
>
> no need, I just wanted to make sure.
> I have marked the flash chip as fully tested and will commit that later
> together with other small changes.
> > Also I did not have the same success with the 1rst bios chip which is not recognized (0Kb) by flashrom, and neither by nvflash under windows (nvflash says : unknown eeprom - BF,008D : this is a SST chip)
> > This is a 2Mbits spi eeprom with a sot-23 package.
>
> sot-23 would be pretty spectacular... because that has only 3 pins ;)
> I believe you mean SOIC-8 instead.
>
> SPI flashes can use a few different ID methods which often share (parts
> of) ID bytes. 0xBF is indeed the SST vendor ID... and 0x8d is even (the
> main) part of a known device: the SST25VF040B. But it should be
> detected ok with flashrom. Can you please send us the log produced with:
> flashrom -p buspirate_spi:dev=COM5 -VVV -o SST25VF040B_probe_spew.log
> Maybe I can spot what/if something is wrong.
>
> The top marking of the chip would also help very much in verifying if
> it is a SST25VF040B or something else.
> -- 
> Kind regards/Mit freundlichen Grüßen, Stefan Tauner

[Stefan Tauner]

On Tue, 6 Jan 2015 11:58:11 +0100
Gilles Auréjac  wrote:
> Hi Stefan,
>
> I understand that it looks strange, but yes it is a small 6-pin package, with I maybe wrongle identified as a 6-pin sot23 (or sot23-6) package.
> I'm not sure about the pinouts, though (I easily found vdd and vcc, bot on other trace are hard to follow on the board of the graphic card)
> Whith a magnifier I only manage to read the two letters YU on the package...
>
> What is strange is with those packages I only found datasheets of smaller eeprom (1k, 2k, but not 1 or 2Mbits which is the attempted size regarding the size of bios of those products)
>
> I'll run the command and send you photos later this day

There exist sot23-6 SPI *EEPROM* chips with the usual EEPROM densities
of a few kilobits, but I don't think there exist any NOR *flash* chips
with such a package. Of course it could be a custom package but I won't
believe it until I see it :)

I believe that nvflash is operating on an entirely different chip than
you do externally with flashrom (I presume you have hooked up an
external programmer to the chip). You should look out for a SOIC-8
chip. Either that or a BGA chip that won't be very easy to interact
with externally...

[Gilles Auréjac]

Le 6 janv. 2015 à 13:44, Stefan Tauner  a écrit :
> There exist sot23-6 SPI *EEPROM* chips with the usual EEPROM densities
> of a few kilobits, but I don't think there exist any NOR *flash* chips
> with such a package. Of course it could be a custom package but I won't
> believe it until I see it :)

I do agree... I will inspect further the board, I may be completely wrong and have follow the wrong trace
I followed a trace from a switch which selects between two bios.

sorry, lot of work and being quite tired last days :-)
> I believe that nvflash is operating on an entirely different chip than
> you do externally with flashrom (I presume you have hooked up an
> external programmer to the chip).

yes
> You should look out for a SOIC-8
> chip. Either that or a BGA chip that won't be very easy to interact
> with externally...

I'll try and let you know , thanks a lot