DragonFlyBSD

Sometimes one must go backwards before one can go forwards. The attached patch updates drm/radeon to Linux 4.7.10 as much as possible, with the obvious exception of patches related to dma_fence, reservation objects, dma_buf, prime, DisplayPort MST, and interval trees. In particular, because I do not have DisplayPort hardware to test, I expect complete breakage.

When I want decent font display without corruption on a CAICOS Sapphire Radeon HD6450 card, I use in a hacked version of pkgsrc for mesa 17 in /usr/pkg/share/X11/xorg.conf.d a 20-glamor.conf file resembling:

Section "Module" 
    Load "dri2" 
    Load "glamoregl" 
EndSection
Section "Device" 
    Identifier "Radeon Graphics" 
    Driver "radeon" 
    Option "AccelMethod" "glamor" 
    Option "ShadowPrimary" "on" 
EndSection

Take out the Option "ShadowPrimary" "on" and there are quite visible artifacts, but I am still able to fire up firefox using

LD_PRELOAD=/usr/pkg/lib/libGL.so firefox &

with layers acceleration forced to get some sort of display in WebGL Water:

http://madebyevan.com/webgl-water/

The patch is radeon47fast.patch generated by git format patch. Also attached is a diff between drm/radeon after the patch compared to Linux 4.7.10's. radeon_4_07.diff shows exactly what is left to be done.

The patch seems to apply cleanly up through at least

commit f30091155bf042c3e2934ca63573dabebe30f556
Date:   Mon Apr 24 19:22:39 2017 +0200

    <fcntl.h>: Add some missing defines (required by POSIX).