By correctly describing the rinbuffers as being in the GTT domain, it appears that we are more careful with the management of the CPU cache upon resume and so prevent some coherency issue when submitting commands to the GPU later. A secondary effect is that the debug logs are then consistent with the actual usage (i.e. they no longer describe the ringbuffers as being in the CPU write domain when we are accessing them through an wc iomapping.) Reported-and-tested-by: Daniel Gnoutcheff <daniel at gnoutcheff.name> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=41092 Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk> --- drivers/gpu/drm/i915/intel_ringbuffer.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 490df55..9fbad08 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -988,6 +988,10 @@ static int intel_init_ring_buffer(struct drm_device *dev, if (ret) goto err_unref; + ret = i915_gem_object_set_to_gtt_domain(obj, true); + if (ret) + goto err_unpin; + ring->virtual_start = ioremap_wc(dev->agp->base + obj->gtt_offset, ring->size); if (ring->virtual_start == NULL) { -- 1.7.10
