drm/i915: Fix tiling pitch handling on 8xx.
The pitch field is an exponent on pre-965, so we were rejecting buffers
on 8xx that we shouldn't have. 915 got lucky in that the largest legal
value happened to match (8KB / 512 = 0x10), but 8xx has a smaller tile width.
Additionally, we programmed that bad value into the register on 8xx, so the
only pitch that would work correctly was 4096 (512-1023 pixels), while others
would probably give bad rendering or hangs.
Signed-off-by: Eric Anholt <eric@anholt.net>
fd.o bug #20473.
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 717b6a8..e4408da 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2128,8 +2128,10 @@
return;
}
- pitch_val = (obj_priv->stride / 128) - 1;
- WARN_ON(pitch_val & ~0x0000000f);
+ pitch_val = obj_priv->stride / 128;
+ pitch_val = ffs(pitch_val) - 1;
+ WARN_ON(pitch_val > I830_FENCE_MAX_PITCH_VAL);
+
val = obj_priv->gtt_offset;
if (obj_priv->tiling_mode == I915_TILING_Y)
val |= 1 << I830_FENCE_TILING_Y_SHIFT;