[Mesa-dev] [PATCH 3/3] i965: Fix integer border color on Haswell.

[Kenneth Graunke]

+82 Piglits - 100% of border color tests now pass on Haswell.

Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
Cc: Chris Forbes <chrisf at ijw.co.nz>
Cc: mesa-stable at lists.freedesktop.org
---
 src/mesa/drivers/dri/i965/brw_defines.h           |  1 +
 src/mesa/drivers/dri/i965/brw_sampler_state.c     | 62 +++++++++++++++++++++++
 src/mesa/drivers/dri/i965/gen7_wm_surface_state.c |  3 ++
 3 files changed, 66 insertions(+)

I finally figured out what the documentation was trying to say!  Buried
within thirteen pages of tables were a few extra bizarre bits - RG is
broken and treated as RB (like it is for textureGather), and 16-bit
skip a DWord for no obvious reason.

With all the strange corner cases in place, everything seems to work.

diff --git a/src/mesa/drivers/dri/i965/brw_defines.h b/src/mesa/drivers/dri/i965/brw_defines.h
index f02a0b8..a597d6b 100644
--- a/src/mesa/drivers/dri/i965/brw_defines.h
+++ b/src/mesa/drivers/dri/i965/brw_defines.h
@@ -551,6 +551,7 @@
 #define BRW_SURFACE_PITCH_MASK		INTEL_MASK(19, 3)
 #define BRW_SURFACE_TILED		(1 << 1)
 #define BRW_SURFACE_TILED_Y		(1 << 0)
+#define HSW_SURFACE_IS_INTEGER_FORMAT   (1 << 18)
 
 /* Surface state DW4 */
 #define BRW_SURFACE_MIN_LOD_SHIFT	28
diff --git a/src/mesa/drivers/dri/i965/brw_sampler_state.c b/src/mesa/drivers/dri/i965/brw_sampler_state.c
index c6a8ab1..be85660 100644
--- a/src/mesa/drivers/dri/i965/brw_sampler_state.c
+++ b/src/mesa/drivers/dri/i965/brw_sampler_state.c
@@ -271,6 +271,68 @@ upload_default_color(struct brw_context *brw,
       uint32_t *sdc = brw_state_batch(brw, AUB_TRACE_SAMPLER_DEFAULT_COLOR,
                                       4 * 4, 64, sdc_offset);
       memcpy(sdc, color.ui, 4 * 4);
+   } else if (brw->is_haswell && texObj->_IsIntegerFormat) {
+      /* Haswell's integer border color support is completely insane:
+       * SAMPLER_BORDER_COLOR_STATE is 20 DWords.  The first four are
+       * for float colors.  The next 12 DWords are MBZ and only exist to
+       * pad it out to a 64 byte cacheline boundary.  DWords 16-19 then
+       * contain integer colors; these are only used if SURFACE_STATE
+       * has the "Integer Surface Format" bit set.  Even then, the
+       * arrangement of the RGBA data devolves into madness.
+       */
+      uint32_t *sdc = brw_state_batch(brw, AUB_TRACE_SAMPLER_DEFAULT_COLOR,
+                                      20 * 4, 512, sdc_offset);
+      memset(sdc, 0, 20 * 4);
+      sdc = &sdc[16];
+
+      mesa_format format = firstImage->TexFormat;
+      int bits_per_channel = _mesa_get_format_bits(format, GL_RED_BITS);
+
+      /* From the Haswell PRM, "Command Reference: Structures", Page 36:
+       * "If any color channel is missing from the surface format,
+       *  corresponding border color should be programmed as zero and if
+       *  alpha channel is missing, corresponding Alpha border color should
+       *  be programmed as 1."
+       */
+      unsigned c[4] = { 0, 0, 0, 1 };
+      for (int i = 0; i < 4; i++) {
+         if (_mesa_format_has_color_component(format, i))
+            c[i] = color.ui[i];
+      }
+
+      switch (bits_per_channel) {
+      case 8:
+         /* Copy RGBA in order. */
+         for (int i = 0; i < 4; i++)
+            ((uint8_t *) sdc)[i] = c[i];
+         break;
+      case 10:
+         /* R10G10B10A2_UINT is treated like a 16-bit format. */
+      case 16:
+         ((uint16_t *) sdc)[0] = c[0]; /* R -> DWord 0, bits 15:0  */
+         ((uint16_t *) sdc)[1] = c[1]; /* G -> DWord 0, bits 31:16 */
+         /* DWord 1 is Reserved/MBZ! */
+         ((uint16_t *) sdc)[4] = c[2]; /* B -> DWord 2, bits 15:0  */
+         ((uint16_t *) sdc)[5] = c[3]; /* A -> DWord 3, bits 31:16 */
+         break;
+      case 32:
+         if (firstImage->_BaseFormat == GL_RG) {
+            /* Careful inspection of the tables reveals that for RG32 formats,
+             * the green channel needs to go where blue normally belongs.
+             */
+            sdc[0] = c[0];
+            sdc[2] = c[1];
+            sdc[3] = 1;
+         } else {
+            /* Copy RGBA in order. */
+            for (int i = 0; i < 4; i++)
+               sdc[i] = c[i];
+         }
+         break;
+      default:
+         assert(!"Invalid number of bits per channel in integer format.");
+         break;
+      }
    } else if (brw->gen == 5 || brw->gen == 6) {
       struct gen5_sampler_default_color *sdc;
 
diff --git a/src/mesa/drivers/dri/i965/gen7_wm_surface_state.c b/src/mesa/drivers/dri/i965/gen7_wm_surface_state.c
index 07db678..29553cd 100644
--- a/src/mesa/drivers/dri/i965/gen7_wm_surface_state.c
+++ b/src/mesa/drivers/dri/i965/gen7_wm_surface_state.c
@@ -321,6 +321,9 @@ gen7_update_texture_surface(struct gl_context *ctx,
    surf[3] = SET_FIELD(effective_depth - 1, BRW_SURFACE_DEPTH) |
              (mt->pitch - 1);
 
+   if (brw->is_haswell && tObj->_IsIntegerFormat)
+      surf[3] |= HSW_SURFACE_IS_INTEGER_FORMAT;
+
    surf[4] = gen7_surface_msaa_bits(mt->num_samples, mt->msaa_layout) |
              SET_FIELD(tObj->MinLayer, GEN7_SURFACE_MIN_ARRAY_ELEMENT) |
              SET_FIELD((effective_depth - 1),
-- 
2.2.2