> There's something weird we encountered.  It seems that memcpy is
> really evil.  We expected PIO read performance to be bad.  It turned
> out to be far worse than we expected.  
>...
> Mind you, when we add acceleration, this will only matter
> for getimage, and even then, only as long as we don't have DMA.

I wouldn't spend much time on this. Any real driver will use DMA to transfer 
between system memory and vram. Many modern cards don't even map most of their 
vram into PCI space, the only way to access it is via DMA.

Even if we don't have DMA I'd expect reading vram to be a fairly exceptional 
case.

Paul
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