[PATCH] drm/amdgpu:fix exclusive mode game texture blank(v2)

[Monk Liu]

this fix DOTA and other exclusive & full screen game
textrue blank bug, the root cause is that when no ctx
switch between two DMAframe, CE go too faster and step
to the next DMAframe, thus DE and CE are not working on
the same DAMframe.

Change-Id: I92714a1d434bb05e94220a2db9b4a6113b0c2efc
Signed-off-by: Monk Liu <Monk.Liu at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c
index 38261a0..4863426 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c
@@ -129,6 +129,7 @@ int amdgpu_ib_schedule(struct amdgpu_ring *ring, unsigned num_ibs,
 
 	unsigned i;
 	int r = 0;
+	unsigned extra_nop = 0;
 
 	if (num_ibs == 0)
 		return -EINVAL;
@@ -155,6 +156,10 @@ int amdgpu_ib_schedule(struct amdgpu_ring *ring, unsigned num_ibs,
 	alloc_size = amdgpu_ring_get_dma_frame_size(ring) +
 		num_ibs * amdgpu_ring_get_emit_ib_size(ring);
 
+	if (job && !job->vm_needs_flush && ring->type == AMDGPU_RING_TYPE_GFX) {
+		extra_nop = 128;
+	}
+
 	r = amdgpu_ring_alloc(ring, alloc_size);
 	if (r) {
 		dev_err(adev->dev, "scheduling IB failed (%d).\n", r);
@@ -165,6 +170,8 @@ int amdgpu_ib_schedule(struct amdgpu_ring *ring, unsigned num_ibs,
 		patch_offset = amdgpu_ring_init_cond_exec(ring);
 
 	if (vm) {
+		amdgpu_ring_insert_nop(ring, extra_nop); /* prevent CE go too fast than DE */
+
 		r = amdgpu_vm_flush(ring, job);
 		if (r) {
 			amdgpu_ring_undo(ring);
-- 
1.9.1