libpan: Add indirect dispatch implementation

Signed-off-by: Mary Guillemard <mary.guillemard@collabora.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/32839>

src/panfrost/libpan/indirect_dispatch.cl

@@ -0,0 +1,65 @@
+/*
+ * Copyright 2024 Collabora Ltd.
+ * SPDX-License-Identifier: MIT
+ */
+
+#include "compiler/libcl/libcl.h"
+#include "compiler/libcl/libcl_vk.h"
+#include "genxml/gen_macros.h"
+#include "lib/pan_encoder.h"
+
+#if (PAN_ARCH >= 6 && PAN_ARCH <= 9)
+KERNEL(1)
+panlib_indirect_dispatch(constant VkDispatchIndirectCommand *cmd,
+                         uint32_t size_x, uint32_t size_y, uint32_t size_z,
+                         global uint8_t *indirect_job,
+                         global uint32_t *num_wg_sysval_x,
+                         global uint32_t *num_wg_sysval_y,
+                         global uint32_t *num_wg_sysval_z)
+{
+   const uint32_t num_x = cmd->x;
+   const uint32_t num_y = cmd->y;
+   const uint32_t num_z = cmd->z;
+
+   /* In case there is nothing to dispatch, set a null job otherwise we ensure
+    * that the type is compute */
+   const bool is_no_op = num_x * num_y * num_z == 0;
+   struct mali_job_header_packed job_header;
+
+   pan_pack(&job_header, JOB_HEADER, cfg) {
+      cfg.type = is_no_op ? MALI_JOB_TYPE_NULL : MALI_JOB_TYPE_COMPUTE;
+   }
+   pan_merge((global struct mali_job_header_packed *)indirect_job, &job_header, JOB_HEADER);
+
+   /* If there is nothing else to do, let's just return now */
+   if (is_no_op)
+      return;
+
+#if PAN_ARCH == 9
+   global struct mali_compute_payload_packed *payload =
+      (global struct mali_compute_payload_packed *)(indirect_job +
+                                                    pan_section_offset(
+                                                       COMPUTE_JOB, PAYLOAD));
+
+   pan_unpack(payload, COMPUTE_PAYLOAD, unpacked_job_payloads);
+   pan_pack(payload, COMPUTE_PAYLOAD, cfg) {
+      memcpy(&cfg, &unpacked_job_payloads, sizeof(cfg));
+      cfg.workgroup_count_x = num_x;
+      cfg.workgroup_count_y = num_y;
+      cfg.workgroup_count_z = num_z;
+   }
+#else
+   global struct mali_invocation_packed *invocation =
+      (global struct mali_invocation_packed *)(indirect_job +
+                                               pan_section_offset(COMPUTE_JOB,
+                                                                  INVOCATION));
+
+   pan_pack_work_groups_compute(invocation, num_x, num_y, num_z, size_x,
+                                size_y, size_z, false, false);
+#endif
+
+   *num_wg_sysval_x = num_x;
+   *num_wg_sysval_y = num_y;
+   *num_wg_sysval_z = num_z;
+}
+#endif

src/panfrost/libpan/meson.build

@@ -4,6 +4,7 @@
 
 libpan_shader_files = files(
   'query_pool.cl',
+  'indirect_dispatch.cl',
 )
 
 idep_libpan_per_arch = {}