isl: Fix row pitch for linear buffers

isl always aligned the row pitch to the surface's image alignment.  This
was sometimes wrong when the surface backed a VkBuffer. For a VkBuffer,
the surface's row pitch is set by VkBufferImageCopy::bufferRowLength,
whose required alignment is only that of the VkFormat.

In particular, VkBuffer rows are packed in many dEQP and Crucible tests.
And packed rows are rarely aligned to the surface's image alignment.

Fixes: dEQP-VK.pipeline.image.view_type.2d.format.r8g8b8a8_unorm.size.13x13

1 files changed, 21 insertions, 1 deletions

diff --git a/src/isl/isl.c b/src/isl/isl.c
index fe878f7fb9a..3823a720660 100644
--- a/src/isl/isl.c
+++ b/src/isl/isl.c
@@ -536,6 +536,25 @@ isl_calc_phys_slice0_extent_sa_gen4_2d(
 {
    assert(phys_level0_sa->depth == 1);
 
+   if (info->levels == 1) {
+      /* Do not align single-level surfaces to the image alignment.
+       *
+       * For tiled surfaces, skipping the alignment here avoids wasting CPU
+       * cycles on the below mipmap layout caluclations. Skipping the
+       * alignment here is safe because we later align the row pitch and array
+       * pitch to the tile boundary. It is safe even for
+       * ISL_MSAA_LAYOUT_INTERLEAVED, because phys_level0_sa is already scaled
+       * to accomodate the interleaved samples.
+       *
+       * For linear surfaces, skipping the alignment here permits us to later
+       * choose an arbitrary, non-aligned row pitch. If the surface backs
+       * a VkBuffer, then an arbitrary pitch may be needed to accomodate
+       * VkBufferImageCopy::bufferRowLength.
+       */
+      *phys_slice0_sa = isl_extent2d(phys_level0_sa->w, phys_level0_sa->h);
+      return;
+   }
+
    uint32_t slice_top_w = 0;
    uint32_t slice_bottom_w = 0;
    uint32_t slice_left_h = 0;
@@ -626,7 +645,8 @@ isl_calc_phys_slice0_extent_sa_gen4_3d(
 
 /**
  * Calculate the physical extent of the surface's first array slice, in units
- * of surface samples. The result is aligned to \a image_align_sa.
+ * of surface samples. If the surface is multi-leveled, then the result will
+ * be aligned to \a image_align_sa.
  */
 static void
 isl_calc_phys_slice0_extent_sa(const struct isl_device *dev,