[Mesa-dev] [PATCH] i965: Add extra-alignment for non-msrt fast color clear for all hw (v2)

[Chad Versace]

The BSpec states that the aligment for the non-msrt clear rectangle must
be doubled; the BSpec does not restricit the workaround to specific
hardware.

Commit 9a1a67b applied the workaround to Haswell GT3.  Commit 8b659ce
expanded the workaround to all Haswell variants. This commit expands it
to all hardware.

No Piglit regressions on Ivybridge 0x0166. No fixes either.

I know no Ivybridge nor Baytrail bug related to this workaround.
However, the BSpec says the extra alignment is required, so let's do it.

v2: Apply to all hardware, not just gen7.

CC: "9.2, 10.0" <mesa-stable at lists.freedesktop.org>
CC: Anuj Phogat <anuj.phogat at gmail.com>
CC: Paul Berry <stereotype441 at gmail.com>
Signed-off-by: Chad Versace <chad.versace at linux.intel.com>
---
 src/mesa/drivers/dri/i965/brw_blorp_clear.cpp | 35 +++++++++------------------
 1 file changed, 11 insertions(+), 24 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_blorp_clear.cpp b/src/mesa/drivers/dri/i965/brw_blorp_clear.cpp
index 3f096b5..1904bde 100644
--- a/src/mesa/drivers/dri/i965/brw_blorp_clear.cpp
+++ b/src/mesa/drivers/dri/i965/brw_blorp_clear.cpp
@@ -265,30 +265,17 @@ brw_blorp_clear_params::brw_blorp_clear_params(struct brw_context *brw,
       x_align *= 16;
       y_align *= 32;
 
-      if (brw->is_haswell) {
-         /* From BSpec: 3D-Media-GPGPU Engine > 3D Pipeline > Pixel > Pixel
-          * Backend > MCS Buffer for Render Target(s) [DevIVB+] > Table "Color
-          * Clear of Non-MultiSampled Render Target Restrictions":
-          *
-          *   [IVB, VLVT, HSW]: Clear rectangle must be aligned to two times
-          *   the number of pixels in the table shown below...  x_align,
-          *   y_align values computed above are the relevant entries in the
-          *   referred table.
-          *
-          * We apply the workaround to only Haswell because (a) we suspect that
-          * is the only hardware where it is actually required and (b) we
-          * haven't yet validated the workaround for the other hardware.
-          */
-         x0 = ROUND_DOWN_TO(x0, 2 * x_align);
-         y0 = ROUND_DOWN_TO(y0, 2 * y_align);
-         x1 = ALIGN(x1, 2 * x_align);
-         y1 = ALIGN(y1, 2 * y_align);
-      } else {
-         x0 = ROUND_DOWN_TO(x0,  x_align);
-         y0 = ROUND_DOWN_TO(y0, y_align);
-         x1 = ALIGN(x1, x_align);
-         y1 = ALIGN(y1, y_align);
-      }
+      /* From BSpec: 3D-Media-GPGPU Engine > 3D Pipeline > Pixel > Pixel
+       * Backend > MCS Buffer for Render Target(s) [DevIVB+] > Table "Color
+       * Clear of Non-MultiSampled Render Target Restrictions":
+       *
+       *   Clear rectangle must be aligned to two times the number of pixels in
+       *   the table shown below due to 16x16 hashing across the slice.
+       */
+      x0 = ROUND_DOWN_TO(x0, 2 * x_align);
+      y0 = ROUND_DOWN_TO(y0, 2 * y_align);
+      x1 = ALIGN(x1, 2 * x_align);
+      y1 = ALIGN(y1, 2 * y_align);
 
       /* From the Ivy Bridge PRM, Vol2 Part1 11.7 "MCS Buffer for Render
        * Target(s)", beneath the "Fast Color Clear" bullet (p327):
-- 
1.8.4