epia m vga + memcpy update

Li-Ta Lo ollie at lanl.gov
Thu Sep 9 12:57:01 CEST 2004


On Thu, 2004-09-09 at 11:58, Richard Smith wrote:
> Li-Ta Lo wrote:
> 
> >>>Did they do anything on the "core" x86emu? Last time I checked,
> >>>XF86 4.4.0 has almost the same x86emu as testbios.
> >>
> >>Something is differnt even with 4.3.  I can run my ATI M1 bios under 
> >>testbios and it dosen't work but X with InitPrimary enabled works.
> >> 
> > Interesting. Do you have any idea why ?
> > 
> 
> Not really.  There's lots of variables.  I do have machines that 
> testbios does work with my M1 bios.  But these machines boot a COTS bios 
> rather than LB.
> 
> For one thing I think the emu in X handles the reads and writes to the 
> timer rather than letting the bios get to the hardware.  The stock M1 
> bios won't run under vgabios at all. The delay functions go into loops 
> that only exit by chance.  The X emu will run that code fine.
> 
> I have a modified version of the M1 bios that works around the delay 
> issue by effectively removing them so it runs under testbios but it 
> still dosen't bring the card to life.  Its possible that my "fix" is 
> part of the problem since timeing can be critical but I wouldn't expect 
> the emulator to running too fast and I don't think too slow would be a 
> problem.
> 

So you still think it is the timer ? Did you try to access the timer
HW in testbios ?

Ollie





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