From 04f15cc71092f566cccc47ca29aead831bdfd634 Mon Sep 17 00:00:00 2001
From: Gert Wollny <gert.wollny@collabora.com>
Date: Mon, 4 May 2026 23:26:47 +0200
Subject: [PATCH] r600/sfn: Add lowering of tess inner and outer default
 intrinsics

These are UBO loads and so we do the lowering in nir.

Signed-off-by: Gert Wollny <gert.wollny@collabora.com>
---
 src/gallium/drivers/r600/sfn/sfn_nir.cpp      |  6 ++-
 .../drivers/r600/sfn/sfn_shader_tess.cpp      | 39 +++++++++++++++++++
 .../drivers/r600/sfn/sfn_shader_tess.h        |  2 +
 3 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/src/gallium/drivers/r600/sfn/sfn_nir.cpp b/src/gallium/drivers/r600/sfn/sfn_nir.cpp
index 613204f4356..0a59584121d 100644
--- a/src/gallium/drivers/r600/sfn/sfn_nir.cpp
+++ b/src/gallium/drivers/r600/sfn/sfn_nir.cpp
@@ -22,6 +22,7 @@
 #include "sfn_nir_lower_tex.h"
 #include "sfn_optimizer.h"
 #include "sfn_ra.h"
+#include "sfn_shader_tess.h"
 #include "sfn_scheduler.h"
 #include "sfn_shader.h"
 #include "sfn_split_address_loads.h"
@@ -869,8 +870,11 @@ r600_lower_and_optimize_nir(nir_shader *sh,
       NIR_PASS(_, sh, r600_lower_tess_io, static_cast<mesa_prim>(prim_type));
    }
 
-   if (sh->info.stage == MESA_SHADER_TESS_CTRL)
+   if (sh->info.stage == MESA_SHADER_TESS_CTRL) {
+      NIR_PASS(_, sh, nir_lower_system_values);
+      NIR_PASS(_, sh, r600_lower_tess_level_default_to_ubo);
       NIR_PASS(_, sh, r600_append_tcs_TF_emission, (mesa_prim)key->tcs.prim_mode);
+   }
 
    if (sh->info.stage == MESA_SHADER_TESS_EVAL) {
       NIR_PASS(_,
diff --git a/src/gallium/drivers/r600/sfn/sfn_shader_tess.cpp b/src/gallium/drivers/r600/sfn/sfn_shader_tess.cpp
index 16c7d0ccb0c..28f4f4a7c96 100644
--- a/src/gallium/drivers/r600/sfn/sfn_shader_tess.cpp
+++ b/src/gallium/drivers/r600/sfn/sfn_shader_tess.cpp
@@ -8,6 +8,8 @@
 
 #include "sfn_instr_export.h"
 #include "sfn_shader_vs.h"
+#include "sfn_nir.h"
+#include "nir.h"
 
 #include <sstream>
 
@@ -245,4 +247,41 @@ TESShader::do_print_properties(std::ostream& os) const
    (void)os;
 }
 
+class LowerTessLevelDefault : public NirLowerInstruction {
+   bool filter(const nir_instr *instr) const override
+   {
+      if (instr->type != nir_instr_type_intrinsic)
+         return false;
+
+      auto intr = nir_instr_as_intrinsic(instr);
+      return intr->intrinsic == nir_intrinsic_load_tess_level_inner_default ||
+             intr->intrinsic == nir_intrinsic_load_tess_level_outer_default;
+   }
+
+   nir_def *lower(nir_instr *instr) override
+   {
+      auto intr = nir_instr_as_intrinsic(instr);
+
+      auto info_buffer = nir_imm_int(b, R600_BUFFER_INFO_CONST_BUFFER);
+
+      switch (intr->intrinsic) {
+      case nir_intrinsic_load_tess_level_inner_default:
+         return  nir_load_ubo(b, 2, 32, info_buffer, nir_imm_int(b, 16),
+                               .range_base = 16, .range = 8);
+      case nir_intrinsic_load_tess_level_outer_default:
+         return nir_load_ubo(b, 4, 32, info_buffer, nir_imm_int(b, 0),
+                             .range_base = 0, .range = 16);
+      default:
+         assert(0);
+         return nullptr;
+      }
+   }
+};
+
 } // namespace r600
+
+int r600_lower_tess_level_default_to_ubo(nir_shader *sh)
+{
+   return r600::LowerTessLevelDefault().run(sh);
+}
+
diff --git a/src/gallium/drivers/r600/sfn/sfn_shader_tess.h b/src/gallium/drivers/r600/sfn/sfn_shader_tess.h
index d932bf46c8e..62410ba69b2 100644
--- a/src/gallium/drivers/r600/sfn/sfn_shader_tess.h
+++ b/src/gallium/drivers/r600/sfn/sfn_shader_tess.h
@@ -83,4 +83,6 @@ private:
 
 } // namespace r600
 
+int r600_lower_tess_level_default_to_ubo(nir_shader *sh);
+
 #endif // TCS_H