Re: [flashrom] Difference of factory bios and dumped image

[Prakash Punnoor]

On Saturday 31 December 2011 13:55:45 Idwer Vollering wrote:
> 2011/12/31 Prakash Punnoor :
> > On 31.12.2011 11:39, Paul Menzel wrote:
> > > Am Samstag, den 31.12.2011, 10:55 +0100 schrieb Prakash Punnoor:
> > > > flashrom kind of works on my system, but not with the factory
> > > > images. If I read it out with flashrom and write it back with
> > > > flashrom (also to a different chip) it works. The sizes of factory
> > > > and dumped image are same but they are somewhat binary different.
> > > > Any idea? The motherboard is Abit A-S78H. As I am playing around
> > > > with coreboot - so far unsuccessfully - I want to know whether
> > > > flashrom is writing the generated image correctly... I can upload
> > > > both images somewhere if interested. This is flashrom output on my
> > > > system:
> > > >
> > > > flashrom v0.9.4-r1395 on Linux 3.2.0-rc7+ (x86_64), built with
> > > > libpci 3.1.7, GCC 4.5.2, little endian
> > > > flashrom is free software, get the source code at
> > > > http://www.flashrom.org
> > > >
> > > > Calibrating delay loop... OK.
> > > > Found chipset "AMD SB700/SB710/SB750/SB850". Enabling flash write...
> > > > OK. This chipset supports the following protocols: LPC, FWH, SPI.
> > > > Found Macronix flash chip "MX25L8005" (1024 kB, SPI) at physical
> > > > address 0xfff00000.
> > > > No operations were specified.
> > >
> > > Unfortunately this question seems not be listed in the FAQ. Most of
> > > the
> > > time some areas differ because the MAC address and other configuration
> > > data of the downloaded images differs [2]. I hope you mean the
> > > downloaded image by factory/vendor image.
> >
> > To clarify:
> > Image I got from vendor web page: Flashed with flashrom won't work
> >
> > (machine doesn't POST). Flashed with awdflash works.
>
> Is the bootblock in the downloaded image intact/present? You can use
> bios_extract: http://cgit.freedesktop.org/~libv/bios_extract
>
> What happens when you reset the CMOS/ESCD data after flashing with
> flashrom? awdflash does that with the /cp parameter, see
> http://www.plasma-online.de/textual/howto/flash_award.html

For what is worth, I tried flashing dumped file and then factory bios on top. 
this worked, so I guess everythign is alright. I'l send a separate mail for 
inclusion in wiki.

Regards,

Prakash