i965/meta: Support 16x MSAA in the meta stencil blit

The destination rectangle is now drawn at 4x4 the size and the shader
code to calculate the sample number is adjusted accordingly.

Acked-by: Ben Widawsky <[email protected]>

1 files changed, 17 insertions, 5 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_meta_stencil_blit.c b/src/mesa/drivers/dri/i965/brw_meta_stencil_blit.c
index cbbb919c6ee..4e9aa949506 100644
--- a/src/mesa/drivers/dri/i965/brw_meta_stencil_blit.c
+++ b/src/mesa/drivers/dri/i965/brw_meta_stencil_blit.c
@@ -163,6 +163,13 @@ static const char *fs_tmpl =
    "      txl_coords.x = ((X & int(0xfff8)) >> 2) | (X & int(0x1));\n"
    "      txl_coords.y = ((Y & int(0xfffc)) >> 1) | (Y & int(0x1));\n"
    "      sample_index = (X & 0x4) | (Y & 0x2) | ((X & 0x2) >> 1);\n"
+   "      break;\n"
+   "   case 16:\n"
+   "      txl_coords.x = ((X & int(0xfff8)) >> 2) | (X & int(0x1));\n"
+   "      txl_coords.y = ((Y & int(0xfff8)) >> 2) | (Y & int(0x1));\n"
+   "      sample_index = (((Y & 0x4) << 1) | (X & 0x4) | (Y & 0x2) |\n"
+   "                      ((X & 0x2) >> 1));\n"
+   "      break;\n"
    "   }\n"
    "}\n"
    "\n"
@@ -313,11 +320,16 @@ adjust_msaa(struct blit_dims *dims, int num_samples)
       dims->dst_x0 *= 2;
       dims->dst_x1 *= 2;
    } else if (num_samples) {
-      const int x_num_samples = num_samples / 2;
-      dims->dst_x0 = ROUND_DOWN_TO(dims->dst_x0 * x_num_samples, num_samples);
-      dims->dst_y0 = ROUND_DOWN_TO(dims->dst_y0 * 2, 4);
-      dims->dst_x1 = ALIGN(dims->dst_x1 * x_num_samples, num_samples);
-      dims->dst_y1 = ALIGN(dims->dst_y1 * 2, 4);
+      const int y_num_samples = num_samples >= 16 ? 4 : 2;
+      const int x_num_samples = num_samples / y_num_samples;
+      dims->dst_x0 = ROUND_DOWN_TO(dims->dst_x0 * x_num_samples,
+                                   x_num_samples * 2);
+      dims->dst_y0 = ROUND_DOWN_TO(dims->dst_y0 * y_num_samples,
+                                   y_num_samples * 2);
+      dims->dst_x1 = ALIGN(dims->dst_x1 * x_num_samples,
+                           x_num_samples * 2);
+      dims->dst_y1 = ALIGN(dims->dst_y1 * y_num_samples,
+                           y_num_samples * 2);
    }
 }