[LinuxBIOS] Via epia-m2 difficulties

Carl-Daniel Hailfinger c-d.hailfinger.devel.2006 at gmx.net
Mon Jan 15 00:53:39 CET 2007


Anton wrote:
> On Thu, 9 Nov 2006 18:37:08 +0100
> Peter Stuge <stuge-linuxbios at cdy.org> wrote:
>> On Thu, Nov 09, 2006 at 03:42:20PM +0100, Kurt André Selbach wrote:
>>> I've managed to extract my videobios image with awardeco and that
>>> gave me a videobios file which was exactly 57344byte, how can i
>>> apply this to my linuxbios.rom file?
>> Hm, this may not be the correct image. I'd suggest dumping the VGA
>> BIOS from when the board is running Linux under the factor BIOS
>> thusly:
> 	I'd rather say the output from awardeco is
> correct. VideoBIOS has to padded later to 64k boundary.
> Dumping from live system may be incorrect for videorom
> bigger than 32k. Contact "Carl-Daniel U. Hailfinger" for
> details.

RAM below 1 MB often does not have enough room to store the full BIOS.
This means parts of the (Video)BIOS may be truncated. I know of a few
laptops where the VideoBIOS size is >32k, but only the first 32k of
it are kept in memory after execution. That's (with a proper
structure) enough for VideoBIOS tasks after bootup (VESA and stuff)
but not enough to actually boot the video card.
The only way to get the full VideoBIOS are Anton's BIOS extraction
tools. The VideoBIOS file is usually padded to 64k with this command:

dd conv=notrunc conv=sync bs=65536 if=extractedvideobios of=vbios.rom

Hope this helps.


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