shithub: plan9front

Download patch

ref: f4880742fd204d538168c8bae11ba2935b2b13d6
parent: 3356e0e731bb8e0f4c82caebe358fae2c8fc9113
author: cinap_lenrek <cinap_lenrek@felloff.net>
date: Sun Nov 12 19:48:46 EST 2017

igfx: allocate backing memory for framebuffer and hw cursor when not done by bios (from qu7uux)

new approach to graphics memory management:

the kernel driver never really cared about the size of stolen memory
directly. that was only to figure out the maximum allocation
to place the hardware cursor image somewhere at the end of the
allocation done by bios.

qu7uux's gm965 bios however wont steal enougth memory for his
native resolution so we have todo it manually.

the userspace igfx driver will figure out how much the bios
allocated by looking at the gtt only. then extend the memory by
creating a "fixed" physical segment.

the kernel driver allocates the memory for the cursor image
from normal kernel memory, and just maps it into the gtt at the
end of the virtual kernel framebuffer aperture.

thanks to qu7uux for the patch.