ac: add ac_choose_spi_color_formats() to common code

It's similar between RADV and RadeonSI.

Signed-off-by: Samuel Pitoiset <[email protected]>
Reviewed-by: Marek Olšák <[email protected]>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5436>

1 files changed, 117 insertions, 0 deletions

diff --git a/src/amd/common/ac_shader_util.c b/src/amd/common/ac_shader_util.c
index 030c07c49ef..eabde97348e 100644
--- a/src/amd/common/ac_shader_util.c
+++ b/src/amd/common/ac_shader_util.c
@@ -288,3 +288,120 @@ ac_get_fs_input_vgpr_cnt(const struct ac_shader_config *config,
 
 	return num_input_vgprs;
 }
+
+void ac_choose_spi_color_formats(unsigned format, unsigned swap,
+				 unsigned ntype, bool is_depth,
+				 struct ac_spi_color_formats *formats)
+{
+   /* Alpha is needed for alpha-to-coverage.
+    * Blending may be with or without alpha.
+    */
+   unsigned normal = 0;      /* most optimal, may not support blending or export alpha */
+   unsigned alpha = 0;       /* exports alpha, but may not support blending */
+   unsigned blend = 0;       /* supports blending, but may not export alpha */
+   unsigned blend_alpha = 0; /* least optimal, supports blending and exports alpha */
+
+   /* Choose the SPI color formats. These are required values for RB+.
+    * Other chips have multiple choices, though they are not necessarily better.
+    */
+   switch (format) {
+   case V_028C70_COLOR_5_6_5:
+   case V_028C70_COLOR_1_5_5_5:
+   case V_028C70_COLOR_5_5_5_1:
+   case V_028C70_COLOR_4_4_4_4:
+   case V_028C70_COLOR_10_11_11:
+   case V_028C70_COLOR_11_11_10:
+   case V_028C70_COLOR_5_9_9_9:
+   case V_028C70_COLOR_8:
+   case V_028C70_COLOR_8_8:
+   case V_028C70_COLOR_8_8_8_8:
+   case V_028C70_COLOR_10_10_10_2:
+   case V_028C70_COLOR_2_10_10_10:
+      if (ntype == V_028C70_NUMBER_UINT)
+         alpha = blend = blend_alpha = normal = V_028714_SPI_SHADER_UINT16_ABGR;
+      else if (ntype == V_028C70_NUMBER_SINT)
+         alpha = blend = blend_alpha = normal = V_028714_SPI_SHADER_SINT16_ABGR;
+      else
+         alpha = blend = blend_alpha = normal = V_028714_SPI_SHADER_FP16_ABGR;
+      break;
+
+   case V_028C70_COLOR_16:
+   case V_028C70_COLOR_16_16:
+   case V_028C70_COLOR_16_16_16_16:
+      if (ntype == V_028C70_NUMBER_UNORM || ntype == V_028C70_NUMBER_SNORM) {
+         /* UNORM16 and SNORM16 don't support blending */
+         if (ntype == V_028C70_NUMBER_UNORM)
+            normal = alpha = V_028714_SPI_SHADER_UNORM16_ABGR;
+         else
+            normal = alpha = V_028714_SPI_SHADER_SNORM16_ABGR;
+
+         /* Use 32 bits per channel for blending. */
+         if (format == V_028C70_COLOR_16) {
+            if (swap == V_028C70_SWAP_STD) { /* R */
+               blend = V_028714_SPI_SHADER_32_R;
+               blend_alpha = V_028714_SPI_SHADER_32_AR;
+            } else if (swap == V_028C70_SWAP_ALT_REV) /* A */
+               blend = blend_alpha = V_028714_SPI_SHADER_32_AR;
+            else
+               assert(0);
+         } else if (format == V_028C70_COLOR_16_16) {
+            if (swap == V_028C70_SWAP_STD) { /* RG */
+               blend = V_028714_SPI_SHADER_32_GR;
+               blend_alpha = V_028714_SPI_SHADER_32_ABGR;
+            } else if (swap == V_028C70_SWAP_ALT) /* RA */
+               blend = blend_alpha = V_028714_SPI_SHADER_32_AR;
+            else
+               assert(0);
+         } else /* 16_16_16_16 */
+            blend = blend_alpha = V_028714_SPI_SHADER_32_ABGR;
+      } else if (ntype == V_028C70_NUMBER_UINT)
+         alpha = blend = blend_alpha = normal = V_028714_SPI_SHADER_UINT16_ABGR;
+      else if (ntype == V_028C70_NUMBER_SINT)
+         alpha = blend = blend_alpha = normal = V_028714_SPI_SHADER_SINT16_ABGR;
+      else if (ntype == V_028C70_NUMBER_FLOAT)
+         alpha = blend = blend_alpha = normal = V_028714_SPI_SHADER_FP16_ABGR;
+      else
+         assert(0);
+      break;
+
+   case V_028C70_COLOR_32:
+      if (swap == V_028C70_SWAP_STD) { /* R */
+         blend = normal = V_028714_SPI_SHADER_32_R;
+         alpha = blend_alpha = V_028714_SPI_SHADER_32_AR;
+      } else if (swap == V_028C70_SWAP_ALT_REV) /* A */
+         alpha = blend = blend_alpha = normal = V_028714_SPI_SHADER_32_AR;
+      else
+         assert(0);
+      break;
+
+   case V_028C70_COLOR_32_32:
+      if (swap == V_028C70_SWAP_STD) { /* RG */
+         blend = normal = V_028714_SPI_SHADER_32_GR;
+         alpha = blend_alpha = V_028714_SPI_SHADER_32_ABGR;
+      } else if (swap == V_028C70_SWAP_ALT) /* RA */
+         alpha = blend = blend_alpha = normal = V_028714_SPI_SHADER_32_AR;
+      else
+         assert(0);
+      break;
+
+   case V_028C70_COLOR_32_32_32_32:
+   case V_028C70_COLOR_8_24:
+   case V_028C70_COLOR_24_8:
+   case V_028C70_COLOR_X24_8_32_FLOAT:
+      alpha = blend = blend_alpha = normal = V_028714_SPI_SHADER_32_ABGR;
+      break;
+
+   default:
+      assert(0);
+      return;
+   }
+
+   /* The DB->CB copy needs 32_ABGR. */
+   if (is_depth)
+      alpha = blend = blend_alpha = normal = V_028714_SPI_SHADER_32_ABGR;
+
+   formats->normal = normal;
+   formats->alpha = alpha;
+   formats->blend = blend;
+   formats->blend_alpha = blend_alpha;
+}