Radeon : Exclude some memory zone

José JORGE lists.jjorge at free.fr
Sun Jan 10 15:38:17 PST 2010

A Domingo 10 Janeiro 2010 21:58:42 Jerome Glisse você escreveu:
> It's doable, i think best way would be to allocate a serie of BO
> covering the damaged area using the new ttm allocator which allow
> to specify addr of BO. Then you need to pin all those BO. Maybe
> the trickier part is to design the commandline argument to allow
> such thing.

Thanks, can this allocation be done to any part of the video mem?
I mean are there some areas that will never be written by the new ttm 
allocator, such as the VESA framebuffer zone, that I suppose is at the very 
beginning of the video memory.

Well, let's see if I manage to understand the TTM code ;-)

>Most GPU memory is interleaved so if one chip is broken you can't just
>ignore it linearly, its probably possible to reconfigure the memory
> controller but I can't imaging a 256-bit memory bus working at 192-bit so
> well, and you'd lose more than one RAM chip.

Well, I think this fact is illustrated by tha way the broken zone shows up : 
only one pixel over eight at 24bpp, one over sixteen at 16bpp, etc.

But the affected pixels are really just a few, so I can hope to get it working.

Thanks for both answers.


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