[OpenBIOS] Reducing OpenBIOS memory footprint

Tarl Neustaedter tarl-b2 at tarl.net
Tue Nov 30 22:27:18 CET 2010


On 2010-11-30 4:14 PM, Mark Cave-Ayland wrote:
> [...]
> I see that for PPC in packages/video.c::init_video the framebuffer is 
> allocated using OFMEM and then mapped 1:1. Blue has suggested that if direct 
> access to the framebuffer is not required then we could try a similar 
> dynamic allocation for SPARC - does anyone how/where OpenBoot stores its VGA 
> framebuffer?

Assuming the AST driver is VGA (I think it is, but I'm not all that familiar 
with VGA), it does a simple map-in of BAR 10 for size 80.0000, and smaller 
amounts for BARs 14 and 18. That probably lands it in the 0xfexx.xxxx window.





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