lib/gpgpu_shader: tooling for preparing and running gpgpu shaders

Implement tooling for building shaders for specific generations.
The library allows you to build and run shader from precompiled blocks
and provides an abstraction layer over gpgpu pipeline.

v8: added asserts after memory allocations.

Signed-off-by: Dominik Grzegorzek <dominik.grzegorzek@intel.com>
Signed-off-by: Christoph Manszewski <christoph.manszewski@intel.com>
Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com>
Acked-by: Zbigniew Kempczyński <zbigniew.kempczynski@intel.com>

3 files changed, 251 insertions, 0 deletions

diff --git a/lib/gpgpu_shader.c b/lib/gpgpu_shader.c
new file mode 100644
index 000000000..3b5ba8222
--- /dev/null
+++ b/lib/gpgpu_shader.c
@@ -0,0 +1,212 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2024 Intel Corporation
+ *
+ * Author: Dominik Grzegorzek <dominik.grzegorzek@intel.com>
+ */
+
+#include <i915_drm.h>
+
+#include "ioctl_wrappers.h"
+#include "gpgpu_shader.h"
+#include "gpu_cmds.h"
+
+#define SUPPORTED_GEN_VER 1200 /* Support TGL and up */
+
+#define PAGE_SIZE 4096
+#define BATCH_STATE_SPLIT 2048
+/* VFE STATE params */
+#define THREADS (1 << 16) /* max value */
+#define GEN8_GPGPU_URB_ENTRIES 1
+#define GPGPU_URB_SIZE 0
+#define GPGPU_CURBE_SIZE 0
+#define GEN7_VFE_STATE_GPGPU_MODE 1
+
+static uint32_t fill_sip(struct intel_bb *ibb,
+			 const uint32_t sip[][4],
+			 const size_t size)
+{
+	uint32_t *sip_dst;
+	uint32_t offset;
+
+	intel_bb_ptr_align(ibb, 16);
+	sip_dst = intel_bb_ptr(ibb);
+	offset = intel_bb_offset(ibb);
+
+	memcpy(sip_dst, sip, size);
+
+	intel_bb_ptr_add(ibb, size);
+
+	return offset;
+}
+
+static void emit_sip(struct intel_bb *ibb, const uint64_t offset)
+{
+	intel_bb_out(ibb, GEN4_STATE_SIP | (3 - 2));
+	intel_bb_out(ibb, lower_32_bits(offset));
+	intel_bb_out(ibb, upper_32_bits(offset));
+}
+
+static void
+__xelp_gpgpu_execfunc(struct intel_bb *ibb,
+		      struct intel_buf *target,
+		      unsigned int x_dim, unsigned int y_dim,
+		      struct gpgpu_shader *shdr,
+		      struct gpgpu_shader *sip,
+		      uint64_t ring, bool explicit_engine)
+{
+	uint32_t interface_descriptor, sip_offset;
+	uint64_t engine;
+
+	intel_bb_add_intel_buf(ibb, target, true);
+
+	intel_bb_ptr_set(ibb, BATCH_STATE_SPLIT);
+
+	interface_descriptor = gen8_fill_interface_descriptor(ibb, target,
+							      shdr->instr,
+							      4 * shdr->size);
+
+	if (sip && sip->size)
+		sip_offset = fill_sip(ibb, sip->instr, 4 * sip->size);
+	else
+		sip_offset = 0;
+
+	intel_bb_ptr_set(ibb, 0);
+
+	/* GPGPU pipeline */
+	intel_bb_out(ibb, GEN7_PIPELINE_SELECT | GEN9_PIPELINE_SELECTION_MASK |
+		     PIPELINE_SELECT_GPGPU);
+
+	gen9_emit_state_base_address(ibb);
+
+	xelp_emit_vfe_state(ibb, THREADS, GEN8_GPGPU_URB_ENTRIES,
+			    GPGPU_URB_SIZE, GPGPU_CURBE_SIZE, true);
+
+	gen7_emit_interface_descriptor_load(ibb, interface_descriptor);
+
+	if (sip_offset)
+		emit_sip(ibb, sip_offset);
+
+	gen8_emit_gpgpu_walk(ibb, 0, 0, x_dim * 16, y_dim);
+
+	intel_bb_out(ibb, MI_BATCH_BUFFER_END);
+	intel_bb_ptr_align(ibb, 32);
+
+	engine = explicit_engine ? ring : I915_EXEC_DEFAULT;
+	intel_bb_exec(ibb, intel_bb_offset(ibb),
+		      engine | I915_EXEC_NO_RELOC, false);
+}
+
+static void
+__xehp_gpgpu_execfunc(struct intel_bb *ibb,
+		      struct intel_buf *target,
+		      unsigned int x_dim, unsigned int y_dim,
+		      struct gpgpu_shader *shdr,
+		      struct gpgpu_shader *sip,
+		      uint64_t ring, bool explicit_engine)
+{
+	struct xehp_interface_descriptor_data idd;
+	uint32_t sip_offset;
+	uint64_t engine;
+
+	intel_bb_add_intel_buf(ibb, target, true);
+
+	intel_bb_ptr_set(ibb, BATCH_STATE_SPLIT);
+
+	xehp_fill_interface_descriptor(ibb, target, shdr->instr,
+				       4 * shdr->size, &idd);
+
+	if (sip && sip->size)
+		sip_offset = fill_sip(ibb, sip->instr, 4 * sip->size);
+	else
+		sip_offset = 0;
+
+	intel_bb_ptr_set(ibb, 0);
+
+	/* GPGPU pipeline */
+	intel_bb_out(ibb, GEN7_PIPELINE_SELECT | GEN9_PIPELINE_SELECTION_MASK |
+		     PIPELINE_SELECT_GPGPU);
+	xehp_emit_state_base_address(ibb);
+	xehp_emit_state_compute_mode(ibb);
+	xehp_emit_state_binding_table_pool_alloc(ibb);
+	xehp_emit_cfe_state(ibb, THREADS);
+
+	if (sip_offset)
+		emit_sip(ibb, sip_offset);
+
+	xehp_emit_compute_walk(ibb, 0, 0, x_dim * 16, y_dim, &idd, 0x0);
+
+	intel_bb_out(ibb, MI_BATCH_BUFFER_END);
+	intel_bb_ptr_align(ibb, 32);
+
+	engine = explicit_engine ? ring : I915_EXEC_DEFAULT;
+	intel_bb_exec(ibb, intel_bb_offset(ibb),
+		      engine | I915_EXEC_NO_RELOC, false);
+}
+
+/**
+ * gpgpu_shader_exec:
+ * @ibb: pointer to initialized intel_bb
+ * @target: pointer to initialized intel_buf to be written by shader/sip
+ * @x_dim: gpgpu/compute walker thread group width
+ * @y_dim: gpgpu/compute walker thread group height
+ * @shdr: shader to be executed
+ * @sip: sip to be executed, can be NULL
+ * @ring: engine index
+ * @explicit_engine: whether to use provided engine index
+ *
+ * Execute provided shader in asynchronous fashion. To wait for completion,
+ * caller has to use the provided ibb handle.
+ */
+void gpgpu_shader_exec(struct intel_bb *ibb,
+		       struct intel_buf *target,
+		       unsigned int x_dim, unsigned int y_dim,
+		       struct gpgpu_shader *shdr,
+		       struct gpgpu_shader *sip,
+		       uint64_t ring, bool explicit_engine)
+{
+	igt_require(shdr->gen_ver >= SUPPORTED_GEN_VER);
+	igt_assert(ibb->size >= PAGE_SIZE);
+	igt_assert(ibb->ptr == ibb->batch);
+
+	if (shdr->gen_ver >= 1250)
+		__xehp_gpgpu_execfunc(ibb, target, x_dim, y_dim, shdr, sip,
+				      ring, explicit_engine);
+	else
+		__xelp_gpgpu_execfunc(ibb, target, x_dim, y_dim, shdr, sip,
+				      ring, explicit_engine);
+}
+
+/**
+ * gpgpu_shader_create:
+ * @fd: drm fd - i915 or xe
+ *
+ * Creates empty shader.
+ *
+ * Returns: pointer to empty shader struct.
+ */
+struct gpgpu_shader *gpgpu_shader_create(int fd)
+{
+	struct gpgpu_shader *shdr = calloc(1, sizeof(struct gpgpu_shader));
+	const struct intel_device_info *info;
+
+	igt_assert(shdr);
+	info = intel_get_device_info(intel_get_drm_devid(fd));
+	shdr->gen_ver = 100 * info->graphics_ver + info->graphics_rel;
+	shdr->max_size = 16 * 4;
+	shdr->code = malloc(4 * shdr->max_size);
+	igt_assert(shdr->code);
+	return shdr;
+}
+
+/**
+ * gpgpu_shader_destroy:
+ * @shdr: pointer to shader struct created with 'gpgpu_shader_create'
+ *
+ * Frees resources of gpgpu_shader struct.
+ */
+void gpgpu_shader_destroy(struct gpgpu_shader *shdr)
+{
+	free(shdr->code);
+	free(shdr);
+}
diff --git a/lib/gpgpu_shader.h b/lib/gpgpu_shader.h
new file mode 100644
index 000000000..02f6f1aad
--- /dev/null
+++ b/lib/gpgpu_shader.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2024 Intel Corporation
+ */
+
+#ifndef GPGPU_SHADER_H
+#define GPGPU_SHADER_H
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+struct intel_bb;
+struct intel_buf;
+
+struct gpgpu_shader {
+	uint32_t gen_ver;
+	uint32_t size;
+	uint32_t max_size;
+	union {
+		uint32_t *code;
+		uint32_t (*instr)[4];
+	};
+};
+
+struct gpgpu_shader *gpgpu_shader_create(int fd);
+void gpgpu_shader_destroy(struct gpgpu_shader *shdr);
+
+void gpgpu_shader_dump(struct gpgpu_shader *shdr);
+
+void gpgpu_shader_exec(struct intel_bb *ibb,
+		       struct intel_buf *target,
+		       unsigned int x_dim, unsigned int y_dim,
+		       struct gpgpu_shader *shdr,
+		       struct gpgpu_shader *sip,
+		       uint64_t ring, bool explicit_engine);
+
+#endif /* GPGPU_SHADER_H */
diff --git a/lib/meson.build b/lib/meson.build
index 4d5140216..7dc99f718 100644
--- a/lib/meson.build
+++ b/lib/meson.build
@@ -72,6 +72,7 @@ lib_sources = [
 	'media_spin.c',
 	'media_fill.c',
 	'gpgpu_fill.c',
+	'gpgpu_shader.c',
 	'gpu_cmds.c',
 	'rendercopy_i915.c',
 	'rendercopy_i830.c',