[Mesa-dev] [PATCH 03/11] intel/isl: Refactor isl_calc_array_pitch_el_rows

[Jason Ekstrand]

Over 90% of the function only applies to ISL_DIM_LAYOUT_GEN4_2D anyway
so we can just handle the other two as special cases at the top.  The
two "generic" cases below the switch only apply on gen9 and above and
only to 3D or CCS surfaces.  This implies that they only apply to
surfaces with ISL_DIM_LAYOUT_GEN4_2D.  Making them look generic is a
lie.
---
 src/intel/isl/isl.c | 93 ++++++++++++++++++++++++++---------------------------
 1 file changed, 46 insertions(+), 47 deletions(-)

diff --git a/src/intel/isl/isl.c b/src/intel/isl/isl.c
index b573f0d..2ead399 100644
--- a/src/intel/isl/isl.c
+++ b/src/intel/isl/isl.c
@@ -729,62 +729,61 @@ isl_calc_array_pitch_el_rows(const struct isl_device *dev,
    uint32_t pitch_sa_rows = 0;
 
    switch (dim_layout) {
+   case ISL_DIM_LAYOUT_GEN4_2D:
+      break; /* Handled below */
    case ISL_DIM_LAYOUT_GEN9_1D:
       /* Each row is an array slice */
-      pitch_sa_rows = 1;
+      return 1;
+   case ISL_DIM_LAYOUT_GEN4_3D:
+      assert(array_pitch_span == ISL_ARRAY_PITCH_SPAN_COMPACT);
+      return isl_align_npot(phys_slice0_sa->h, image_align_sa->h);
+   default:
+      unreachable("bad isl_dim_layout");
       break;
-   case ISL_DIM_LAYOUT_GEN4_2D:
-      switch (array_pitch_span) {
-      case ISL_ARRAY_PITCH_SPAN_COMPACT:
-         pitch_sa_rows = isl_align_npot(phys_slice0_sa->h, image_align_sa->h);
-         break;
-      case ISL_ARRAY_PITCH_SPAN_FULL: {
-         /* The QPitch equation is found in the Broadwell PRM >> Volume 5:
-          * Memory Views >> Common Surface Formats >> Surface Layout >> 2D
-          * Surfaces >> Surface Arrays.
-          */
-         uint32_t H0_sa = phys_level0_sa->h;
-         uint32_t H1_sa = isl_minify(H0_sa, 1);
+   }
 
-         uint32_t h0_sa = isl_align_npot(H0_sa, image_align_sa->h);
-         uint32_t h1_sa = isl_align_npot(H1_sa, image_align_sa->h);
+   switch (array_pitch_span) {
+   case ISL_ARRAY_PITCH_SPAN_COMPACT:
+      pitch_sa_rows = isl_align_npot(phys_slice0_sa->h, image_align_sa->h);
+      break;
+   case ISL_ARRAY_PITCH_SPAN_FULL: {
+      /* The QPitch equation is found in the Broadwell PRM >> Volume 5:
+       * Memory Views >> Common Surface Formats >> Surface Layout >> 2D
+       * Surfaces >> Surface Arrays.
+       */
+      uint32_t H0_sa = phys_level0_sa->h;
+      uint32_t H1_sa = isl_minify(H0_sa, 1);
 
-         uint32_t m;
-         if (ISL_DEV_GEN(dev) >= 7) {
-            /* The QPitch equation changed slightly in Ivybridge. */
-            m = 12;
-         } else {
-            m = 11;
-         }
+      uint32_t h0_sa = isl_align_npot(H0_sa, image_align_sa->h);
+      uint32_t h1_sa = isl_align_npot(H1_sa, image_align_sa->h);
 
-         pitch_sa_rows = h0_sa + h1_sa + (m * image_align_sa->h);
+      uint32_t m;
+      if (ISL_DEV_GEN(dev) >= 7) {
+         /* The QPitch equation changed slightly in Ivybridge. */
+         m = 12;
+      } else {
+         m = 11;
+      }
 
-         if (ISL_DEV_GEN(dev) == 6 && info->samples > 1 &&
-             (info->height % 4 == 1)) {
-            /* [SNB] Errata from the Sandy Bridge PRM >> Volume 4 Part 1:
-             * Graphics Core >> Section 7.18.3.7: Surface Arrays:
-             *
-             *    [SNB] Errata: Sampler MSAA Qpitch will be 4 greater than
-             *    the value calculated in the equation above , for every
-             *    other odd Surface Height starting from 1 i.e. 1,5,9,13.
-             *
-             * XXX(chadv): Is the errata natural corollary of the physical
-             * layout of interleaved samples?
-             */
-            pitch_sa_rows += 4;
-         }
+      pitch_sa_rows = h0_sa + h1_sa + (m * image_align_sa->h);
 
-         pitch_sa_rows = isl_align_npot(pitch_sa_rows, fmtl->bh);
-         } /* end case */
-         break;
+      if (ISL_DEV_GEN(dev) == 6 && info->samples > 1 &&
+          (info->height % 4 == 1)) {
+         /* [SNB] Errata from the Sandy Bridge PRM >> Volume 4 Part 1:
+          * Graphics Core >> Section 7.18.3.7: Surface Arrays:
+          *
+          *    [SNB] Errata: Sampler MSAA Qpitch will be 4 greater than
+          *    the value calculated in the equation above , for every
+          *    other odd Surface Height starting from 1 i.e. 1,5,9,13.
+          *
+          * XXX(chadv): Is the errata natural corollary of the physical
+          * layout of interleaved samples?
+          */
+         pitch_sa_rows += 4;
       }
-      break;
-   case ISL_DIM_LAYOUT_GEN4_3D:
-      assert(array_pitch_span == ISL_ARRAY_PITCH_SPAN_COMPACT);
-      pitch_sa_rows = isl_align_npot(phys_slice0_sa->h, image_align_sa->h);
-      break;
-   default:
-      unreachable("bad isl_dim_layout");
+
+      pitch_sa_rows = isl_align_npot(pitch_sa_rows, fmtl->bh);
+      } /* end case */
       break;
    }
 
-- 
2.5.0.400.gff86faf