From 3eef0c02453b59ed6380338fde8edd3063dd4227 Mon Sep 17 00:00:00 2001
From: Dave Airlie <airlied@redhat.com>
Date: Mon, 18 Aug 2025 11:32:40 +1000
Subject: [PATCH] radv: add support for cooperative matrix per element
 operations.

Reviewed-by: Georg Lehmann <dadschoorse@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/36992>
---
 .../nir/radv_nir_lower_cooperative_matrix.c   | 75 +++++++++++++++++++
 src/amd/vulkan/radv_physical_device.c         |  1 +
 2 files changed, 76 insertions(+)

diff --git a/src/amd/vulkan/nir/radv_nir_lower_cooperative_matrix.c b/src/amd/vulkan/nir/radv_nir_lower_cooperative_matrix.c
index 7dc242b3ce6..7998078e43d 100644
--- a/src/amd/vulkan/nir/radv_nir_lower_cooperative_matrix.c
+++ b/src/amd/vulkan/nir/radv_nir_lower_cooperative_matrix.c
@@ -983,6 +983,78 @@ lower_cmat_deref(nir_deref_instr *deref, struct hash_table *type_map, const lowe
    return false;
 }
 
+static bool
+lower_cmat_per_element_op(nir_builder *b, nir_cmat_call_instr *call, const lower_cmat_params *params)
+{
+   nir_def *src = radv_nir_load_cmat(b, params, call->params[3].ssa);
+   nir_deref_instr *dst_deref = nir_src_as_deref(call->params[0]);
+   nir_function *fnptr = call->callee;
+
+   struct glsl_cmat_description desc = *glsl_get_cmat_description(dst_deref->type);
+
+   nir_variable *elem_tmp = nir_local_variable_create(b->impl, glsl_get_cmat_element(dst_deref->type), "elemtmp");
+   nir_deref_instr *elem_deref = nir_build_deref_var(b, elem_tmp);
+   nir_def *local_idx = nir_load_subgroup_invocation(b);
+   nir_def *inner_idx = nir_iand_imm(b, local_idx, 15);
+   unsigned length = radv_nir_cmat_length(desc, params);
+   unsigned mul = radv_nir_cmat_length_mul(desc, params);
+   unsigned lanes_per_iter = desc.use == GLSL_CMAT_USE_ACCUMULATOR ? params->wave_size : 16;
+   nir_def *base_row = radv_get_base_row(b, desc, params, local_idx);
+   nir_def *vars[16];
+
+   if (mul > 1) {
+      for (unsigned i = 0; i < length; ++i)
+         if (i % mul != 0)
+            vars[i] = nir_undef(b, 1, radv_nir_cmat_bits(desc));
+   }
+
+   for (unsigned i = 0; i < length / mul; i++) {
+      nir_def *src_elem = nir_channel(b, src, i * mul);
+      nir_call_instr *new_call = nir_call_instr_create(b->shader, fnptr);
+      uint32_t row_iter;
+
+      if (params->gfx_level >= GFX12) {
+         row_iter = i;
+      } else {
+         row_iter = i * lanes_per_iter / 16;
+      }
+
+      nir_def *row_val = nir_iadd_imm(b, base_row, row_iter);
+      nir_def *col_val = inner_idx;
+
+      if (desc.use == GLSL_CMAT_USE_A)
+         SWAP(col_val, row_val);
+
+      row_val = nir_iadd(b, call->params[1].ssa, row_val);
+      col_val = nir_iadd(b, call->params[2].ssa, col_val);
+
+      new_call->params[0] = nir_src_for_ssa(&elem_deref->def);
+      new_call->params[1] = nir_src_for_ssa(row_val);
+      new_call->params[2] = nir_src_for_ssa(col_val);
+      new_call->params[3] = nir_src_for_ssa(src_elem);
+
+      for (unsigned p = 4; p < call->num_params; p++) {
+         nir_deref_instr *deref = nir_src_as_deref(call->params[p]);
+         nir_def *def = call->params[p].ssa;
+         if (deref) {
+            if (glsl_type_is_cmat(deref->type)) {
+               def = nir_build_load_deref(b, radv_nir_cmat_length(desc, params), radv_nir_cmat_bits(desc), def);
+               def = nir_channel(b, def, i * mul);
+            }
+         }
+         new_call->params[p] = nir_src_for_ssa(def);
+      }
+      nir_builder_instr_insert(b, &new_call->instr);
+      vars[i * mul] = nir_build_load_deref(b, 1, radv_nir_cmat_bits(desc), &elem_deref->def, 0);
+   }
+
+   nir_def *mat = nir_vec(b, vars, length);
+   nir_store_deref(b, dst_deref, mat, nir_component_mask(src->num_components));
+
+   nir_instr_remove(&call->instr);
+   return true;
+}
+
 bool
 radv_nir_lower_cooperative_matrix(nir_shader *shader, enum amd_gfx_level gfx_level, unsigned wave_size)
 {
@@ -1084,6 +1156,9 @@ radv_nir_lower_cooperative_matrix(nir_shader *shader, enum amd_gfx_level gfx_lev
             case nir_cmat_call_op_reduce_2x2:
                progress |= lower_cmat_reduce_2x2_call(&b, call, &params);
                break;
+            case nir_cmat_call_op_per_element_op:
+               progress |= lower_cmat_per_element_op(&b, call, &params);
+               break;
             default:
                break;
             }
diff --git a/src/amd/vulkan/radv_physical_device.c b/src/amd/vulkan/radv_physical_device.c
index b1bb946fdf4..256ec797392 100644
--- a/src/amd/vulkan/radv_physical_device.c
+++ b/src/amd/vulkan/radv_physical_device.c
@@ -1403,6 +1403,7 @@ radv_physical_device_get_features(const struct radv_physical_device *pdev, struc
       .cooperativeMatrixConversions = true,
       .cooperativeMatrixFlexibleDimensions = true,
       .cooperativeMatrixReductions = true,
+      .cooperativeMatrixPerElementOperations = true,
 
       /* VK_KHR_video_encode_av1 */
       .videoEncodeAV1 = true,