Am 07.03.2018 um 10:53 schrieb Michel Dänzer: > On 2018-03-07 10:47 AM, Christian König wrote: >> See when I tested this the DDX and Mesa where unmodified, so both still >> assumed VRAM as placement for scanout BOs, but the kernel forced scanout >> BOs into GTT for testing. >> >> So what happened was that on scanout we moved the VRAM BO to GTT and >> after unpinning it on the first command submission which used the BO we >> moved it back to VRAM again. >> >> So as long as we don't want a severe performance penalty when you >> combine old userspace with new kernel using a kernel parameter to force >> scanout from GTT is not possible. > That means we either need to come up with a different workaround for > hardware issues transitioning between scanout from VRAM and GTT, or we > can't scan out from GTT in that case. What exactly was the problem with the transition from VRAM to GTT? I mean what we can rather easily do is check where the existing BO is pinned and then always pin into the same domain on page flip. Christian.
