pan/lib: introduce row_align_B and array_align_B constraints

To implement sparse partially-resident images, we need to be able
to express mapping in terms of rectangles of texel blocks.

With row_align_B we can constrain the rows of ordered blocks to
start at mapping boundary (i.e. page size) and using array_align_B
we can ensure that each subresource starts at a multiple of
whatever sparse block size we decide to use.

Not setting each of these fields is the same as setting them to 1.

Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/37483>

src/panfrost/lib/pan_layout.c

@@ -160,6 +160,12 @@ pan_image_layout_init(
    /* Arrays and cubemaps have the entire miptree duplicated */
    layout->array_stride_B =
       ALIGN_POT(layout_constraints.offset_B - layout->slices[0].offset_B, 64);
+
+   if (layout_constraints.array_align_B) {
+      layout->array_stride_B =
+         ALIGN_POT(layout->array_stride_B, layout_constraints.array_align_B);
+   }
+
    if (use_explicit_layout) {
       layout->data_size_B =
          layout_constraints.offset_B - explicit_layout_constraints->offset_B;

src/panfrost/lib/pan_layout.h

@@ -132,9 +132,20 @@ struct pan_image_layout_constraints {
     */
    uint64_t offset_B;
 
+   /* Minimal aligment for an array layer. Used to implement sparse residency. */
+   uint32_t array_align_B;
+
    /* Row pitch in bytes. Non-zero if layout is explicit. */
    uint32_t wsi_row_pitch_B;
 
+   union {
+      struct {
+         /* Minimal alignment for a row of ordered blocks. Used to implement sparse
+         * residency. */
+         uint32_t row_align_B;
+      } u_tiled;
+   };
+
    /* When true, AFBC/AFRC imports are stricter than they were when those
     * modifiers where introduced. */
    bool strict;

src/panfrost/lib/pan_mod.c

@@ -546,6 +546,12 @@ pan_mod_u_tiled_init_slice_layout(
          align_mask + 1);
    }
 
+   if (layout_constraints && layout_constraints->u_tiled.row_align_B) {
+      slayout->tiled_or_linear.row_stride_B =
+         ALIGN_POT(slayout->tiled_or_linear.row_stride_B,
+                   layout_constraints->u_tiled.row_align_B);
+   }
+
    uint64_t surf_stride_B =
       (uint64_t)slayout->tiled_or_linear.row_stride_B *
       DIV_ROUND_UP(mip_extent_el.height, tile_extent_el.height);