This time, abandon the use of busdma and start interacting with the VM
system directly. Make use of the new kmem_alloc_attr() which allows us
to easily allocate non-contiguous pages to back the GART table. This
should help a lot when starting or restarting X after the system has
been running for a while and memory has become fragmented.
MFC after: 2 weeks
* On 32 bit platforms we steal the upper 4 bits of the map handle
to store a unique map id.
* On 64 bit platforms we steal the upper 24 bits.
Resolves issues where the offsets that are handed to mmap may overlap the VRAM on some cards.
Tested on: radeon, intel, mga, and via.
This will break nouveau. I will spin new patches shortly.
Tested on an HD3850 (RV670) on loan from Warren Block.
Currently, you need one of the following for this to be useful:
x11-drivers/xf86-video-radeonhd-devel (not tested)
xf86-video-ati from git (EXA works, xv is too fast)
xf86-video-radeonhd from git (EXA works, xv works)
There is no 3d support available from dri just yet.
MFC after: 2 weeks
