From 01bad67a940c234e325e17a37afe076b47ac9ad1 Mon Sep 17 00:00:00 2001
From: Chad Versace <chad@kiwitree.net>
Date: Tue, 25 Aug 2020 10:35:24 -0700
Subject: [PATCH] isl: Define isl_drm_modifier_get_score() [v3]

Return the modifier's score, which indicates the driver's preference for the
modifier relative to others. A higher score is better. Zero means
unsupported.

Intended to assist selection of a modifier from an externally provided list,
such as VkImageDrmFormatModifierListCreateInfoEXT.

v2:
  - Rename anv_drm_format_mod_score to isl_drm_modifier_get_score.
  - Squash all incremental changes to anv_drm_format_mod_score.
v3:
  - Drop redundant 'unlikely'. (for nchery)

Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com> (v2)
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net> (v3)
---
 src/intel/isl/isl.h     | 12 ++++++++++++
 src/intel/isl/isl_drm.c | 27 +++++++++++++++++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/src/intel/isl/isl.h b/src/intel/isl/isl.h
index 4e805867d6a..378caa9fe8f 100644
--- a/src/intel/isl/isl.h
+++ b/src/intel/isl/isl.h
@@ -1892,6 +1892,18 @@ isl_drm_modifier_get_default_aux_state(uint64_t modifier)
                                            ISL_AUX_STATE_COMPRESSED_NO_CLEAR;
 }
 
+/**
+ * Return the modifier's score, which indicates the driver's preference for the
+ * modifier relative to others. A higher score is better. Zero means
+ * unsupported.
+ *
+ * Intended to assist selection of a modifier from an externally provided list,
+ * such as VkImageDrmFormatModifierListCreateInfoEXT.
+ */
+uint32_t
+isl_drm_modifier_get_score(const struct gen_device_info *devinfo,
+                           uint64_t modifier);
+
 struct isl_extent2d ATTRIBUTE_CONST
 isl_get_interleaved_msaa_px_size_sa(uint32_t samples);
 
diff --git a/src/intel/isl/isl_drm.c b/src/intel/isl/isl_drm.c
index e1cae671ec6..04b50fc7912 100644
--- a/src/intel/isl/isl_drm.c
+++ b/src/intel/isl/isl_drm.c
@@ -29,6 +29,7 @@
 
 #include "isl.h"
 #include "dev/gen_device_info.h"
+#include "dev/gen_debug.h"
 
 uint32_t
 isl_tiling_to_i915_tiling(enum isl_tiling tiling)
@@ -121,3 +122,29 @@ isl_drm_modifier_get_info(uint64_t modifier)
 
    return NULL;
 }
+
+uint32_t
+isl_drm_modifier_get_score(const struct gen_device_info *devinfo,
+                           uint64_t modifier)
+{
+   /* FINISHME: Add gen12 modifiers */
+   switch (modifier) {
+   default:
+      return 0;
+   case DRM_FORMAT_MOD_LINEAR:
+      return 1;
+   case I915_FORMAT_MOD_X_TILED:
+      return 2;
+   case I915_FORMAT_MOD_Y_TILED:
+      return 3;
+   case I915_FORMAT_MOD_Y_TILED_CCS:
+      /* Gen12's CCS layout differs from Gen9-11. */
+      if (devinfo->gen >= 12)
+         return 0;
+
+      if (INTEL_DEBUG & DEBUG_NO_RBC)
+         return 0;
+
+      return 4;
+   }
+}