[coreboot] SGABIOS checksum [kevin at koconnor.net: Re: SeaBIOS, serial output, and grub]

[Nathan Laredo]

I already have a fix for this not yet committed -- including
calculation of the rom size byte in the linker script as well as doing
the 2KB alignment of the end of the rom.

I will try to get the new code checked in within the month.   Please
poke me again if you haven't seen updates before the end of May (I
have a new baby at home now).

- nathan laredo
nil at google.com

On Thu, May 14, 2009 at 06:38, Peter Stuge <peter at stuge.se> wrote:
> Hi Nathan,
>
> there was some discussion on the coreboot mailing list, and it seems
> that the SGABIOS binary doesn't have a checksum calculated for it,
> which means that some BIOSes refuse to initialize it.
>
> The SeaBIOS project maintained by Kevin has a utility for calculating
> checksums, available at:
>
> http://git.linuxtogo.org/?p=kevin/seabios.git;a=blob;f=tools/checksum.py;h=8c7665d2508d598abf07510234515ffbf198cdff;hb=HEAD
>
>
> Kevin, I can't find that buildrom.py script in seabios.git?
>
>
> //Peter
>
> ----- Forwarded message from Kevin O'Connor <kevin at koconnor.net> -----
>
> From: Kevin O'Connor <kevin at koconnor.net>
> To: coreboot at coreboot.org
> Subject: Re: [coreboot] SeaBIOS, serial output, and grub
> Date: Thu, 14 May 2009 09:19:33 -0400
>
> On Wed, May 13, 2009 at 11:23:52PM -0400, Ward Vandewege wrote:
>> > which is correct (the last two digits are 00).
>>
>> Huh:
>>
>> $ v ../payloads/sgabios.bin
>> -rwxr-xr-x 1 root src 3169 2009-04-29 13:56 ../payloads/sgabios.bin*
>> $ tools/checksum.py <../payloads/sgabios.bin
>> sum=50b76
>
> Heh - sgabios isn't properly checksumming.  It was just dumb luck that
> my binary summed to zero.
>
> This is a hack, but you can use seabios' rom building tool to make it
> work:
>
> tools/buildrom.py ../payloads/sgabios.bin sgabios-cksum.bin
>
> Someone should follow up with google on this..
>
> -Kevin
>
> --
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>
> ----- End forwarded message -----
>