gem_stress: implement gen5 blitter work-around

ddx and mesa assume that this is issued after every blit command.
Breaking that invariant results in a dying gpu.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/tests/gem_stress.c b/tests/gem_stress.c
index 1a31ab3..62e91c0 100644 (file)
--- a/tests/gem_stress.c
+++ b/tests/gem_stress.c
@@ -66,6 +66,8 @@
 #include "intel_batchbuffer.h"
 #include "intel_gpu_tools.h"
 
+#define CMD_POLY_STIPPLE_OFFSET       0x7906
+
 /** TODO:
  * - beat on relaxed fencing (i.e. mappable/fenceable tracking in the kernel)
  * - render copy (to check fence tracking and cache coherency management by the
@@ -164,6 +166,13 @@ static void keep_gpu_busy(void)
        OUT_BATCH(src_pitch);
        OUT_RELOC(busy_bo, I915_GEM_DOMAIN_RENDER, 0, 0);
        ADVANCE_BATCH();
+
+       if (IS_GEN5(devid)) {
+               BEGIN_BATCH(2);
+               OUT_BATCH(CMD_POLY_STIPPLE_OFFSET << 16);
+               OUT_BATCH(0);
+               ADVANCE_BATCH();
+       }
 }
 
 static unsigned int copyfunc_seq = 0;
@@ -279,6 +288,13 @@ static void blitter_copyfunc(struct scratch_buf *src, unsigned src_x, unsigned s
        OUT_RELOC(src->bo, I915_GEM_DOMAIN_RENDER, 0, 0);
        ADVANCE_BATCH();
 
+       if (IS_GEN5(devid)) {
+               BEGIN_BATCH(2);
+               OUT_BATCH(CMD_POLY_STIPPLE_OFFSET << 16);
+               OUT_BATCH(0);
+               ADVANCE_BATCH();
+       }
+
        if (!(keep_gpu_busy_counter & 1) && !fence_storm)
                keep_gpu_busy();