softpipe: add support for compute shaders. (v2)

This enables ARB_compute_shader on softpipe. I've only
tested this with piglit so far, and I hopefully plan
on integrating it with my vulkan work. I'll get to
testing it with deqp more later.

The basic premise is to create up to 1024 restartable
TGSI machines, and execute workgroups of those machines.

v1.1: free machines.
v2: deqp fixes - add samplers support, finish
atomic operations, fix load/store writemasks.

Acked-by: Roland Scheidegger <[email protected]>
Signed-off-by: Dave Airlie <[email protected]>

1 files changed, 235 insertions, 0 deletions

diff --git a/src/gallium/drivers/softpipe/sp_compute.c b/src/gallium/drivers/softpipe/sp_compute.c
new file mode 100644
index 00000000000..d5b5913f6a2
--- /dev/null
+++ b/src/gallium/drivers/softpipe/sp_compute.c
@@ -0,0 +1,235 @@
+/*
+ * Copyright 2016 Red Hat.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * on the rights to use, copy, modify, merge, publish, distribute, sub
+ * license, and/or sell copies of the Software, and to permit persons to whom
+ * the Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHOR(S) AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+ * USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include "util/u_inlines.h"
+#include "util/u_math.h"
+#include "util/u_memory.h"
+#include "util/u_pstipple.h"
+#include "pipe/p_shader_tokens.h"
+#include "draw/draw_context.h"
+#include "draw/draw_vertex.h"
+#include "sp_context.h"
+#include "sp_screen.h"
+#include "sp_state.h"
+#include "sp_texture.h"
+#include "sp_tex_sample.h"
+#include "sp_tex_tile_cache.h"
+#include "tgsi/tgsi_parse.h"
+
+static void
+cs_prepare(const struct sp_compute_shader *cs,
+           struct tgsi_exec_machine *machine,
+           int w, int h, int d,
+           int g_w, int g_h, int g_d,
+           int b_w, int b_h, int b_d,
+           struct tgsi_sampler *sampler,
+           struct tgsi_image *image,
+           struct tgsi_buffer *buffer )
+{
+   int j;
+   /*
+    * Bind tokens/shader to the interpreter's machine state.
+    */
+   tgsi_exec_machine_bind_shader(machine,
+                                 cs->tokens,
+                                 sampler, image, buffer);
+
+   if (machine->SysSemanticToIndex[TGSI_SEMANTIC_THREAD_ID] != -1) {
+      unsigned i = machine->SysSemanticToIndex[TGSI_SEMANTIC_THREAD_ID];
+      for (j = 0; j < TGSI_QUAD_SIZE; j++) {
+         machine->SystemValue[i].xyzw[0].i[j] = w;
+         machine->SystemValue[i].xyzw[1].i[j] = h;
+         machine->SystemValue[i].xyzw[2].i[j] = d;
+      }
+   }
+
+   if (machine->SysSemanticToIndex[TGSI_SEMANTIC_GRID_SIZE] != -1) {
+      unsigned i = machine->SysSemanticToIndex[TGSI_SEMANTIC_GRID_SIZE];
+      for (j = 0; j < TGSI_QUAD_SIZE; j++) {
+         machine->SystemValue[i].xyzw[0].i[j] = g_w;
+         machine->SystemValue[i].xyzw[1].i[j] = g_h;
+         machine->SystemValue[i].xyzw[2].i[j] = g_d;
+      }
+   }
+
+   if (machine->SysSemanticToIndex[TGSI_SEMANTIC_BLOCK_SIZE] != -1) {
+      unsigned i = machine->SysSemanticToIndex[TGSI_SEMANTIC_BLOCK_SIZE];
+      for (j = 0; j < TGSI_QUAD_SIZE; j++) {
+         machine->SystemValue[i].xyzw[0].i[j] = b_w;
+         machine->SystemValue[i].xyzw[1].i[j] = b_h;
+         machine->SystemValue[i].xyzw[2].i[j] = b_d;
+      }
+   }
+}
+
+static bool
+cs_run(const struct sp_compute_shader *cs,
+       int g_w, int g_h, int g_d,
+       struct tgsi_exec_machine *machine, bool restart)
+{
+   if (!restart) {
+      if (machine->SysSemanticToIndex[TGSI_SEMANTIC_BLOCK_ID] != -1) {
+         unsigned i = machine->SysSemanticToIndex[TGSI_SEMANTIC_BLOCK_ID];
+         int j;
+         for (j = 0; j < TGSI_QUAD_SIZE; j++) {
+            machine->SystemValue[i].xyzw[0].i[j] = g_w;
+            machine->SystemValue[i].xyzw[1].i[j] = g_h;
+            machine->SystemValue[i].xyzw[2].i[j] = g_d;
+         }
+      }
+      machine->NonHelperMask = (1 << 1) - 1;
+   }
+
+   tgsi_exec_machine_run(machine, restart ? machine->pc : 0);
+
+   if (machine->pc != -1)
+      return true;
+   return false;
+}
+
+static void
+run_workgroup(const struct sp_compute_shader *cs,
+              int g_w, int g_h, int g_d, int num_threads,
+              struct tgsi_exec_machine **machines)
+{
+   int i;
+   bool grp_hit_barrier, restart_threads = false;
+
+   do {
+      grp_hit_barrier = false;
+      for (i = 0; i < num_threads; i++) {
+         grp_hit_barrier |= cs_run(cs, g_w, g_h, g_d, machines[i], restart_threads);
+      }
+      restart_threads = false;
+      if (grp_hit_barrier) {
+         grp_hit_barrier = false;
+         restart_threads = true;
+      }
+   } while (restart_threads);
+}
+
+static void
+cs_delete(const struct sp_compute_shader *cs,
+          struct tgsi_exec_machine *machine)
+{
+   if (machine->Tokens == cs->tokens) {
+      tgsi_exec_machine_bind_shader(machine, NULL, NULL, NULL, NULL);
+   }
+}
+
+static void
+fill_grid_size(struct pipe_context *context,
+               const struct pipe_grid_info *info,
+               uint32_t grid_size[3])
+{
+   struct pipe_transfer *transfer;
+   uint32_t *params;
+   if (!info->indirect) {
+      grid_size[0] = info->grid[0];
+      grid_size[1] = info->grid[1];
+      grid_size[2] = info->grid[2];
+      return;
+   }
+   params = pipe_buffer_map_range(context, info->indirect,
+                                  info->indirect_offset,
+                                  3 * sizeof(uint32_t),
+                                  PIPE_TRANSFER_READ,
+                                  &transfer);
+
+   if (!transfer)
+      return;
+
+   grid_size[0] = params[0];
+   grid_size[1] = params[1];
+   grid_size[2] = params[2];
+   pipe_buffer_unmap(context, transfer);
+}
+
+void
+softpipe_launch_grid(struct pipe_context *context,
+                     const struct pipe_grid_info *info)
+{
+   struct softpipe_context *softpipe = softpipe_context(context);
+   struct sp_compute_shader *cs = softpipe->cs;
+   int num_threads_in_group;
+   struct tgsi_exec_machine **machines;
+   int bwidth, bheight, bdepth;
+   int w, h, d, i;
+   int g_w, g_h, g_d;
+   uint32_t grid_size[3];
+   void *local_mem = NULL;
+
+   softpipe_update_compute_samplers(softpipe);
+   bwidth = cs->info.properties[TGSI_PROPERTY_CS_FIXED_BLOCK_WIDTH];
+   bheight = cs->info.properties[TGSI_PROPERTY_CS_FIXED_BLOCK_HEIGHT];
+   bdepth = cs->info.properties[TGSI_PROPERTY_CS_FIXED_BLOCK_DEPTH];
+   num_threads_in_group = bwidth * bheight * bdepth;
+
+   fill_grid_size(context, info, grid_size);
+
+   if (cs->shader.req_local_mem) {
+      local_mem = CALLOC(1, cs->shader.req_local_mem);
+   }
+
+   machines = CALLOC(sizeof(struct tgsi_exec_machine *), num_threads_in_group);
+   if (!machines)
+      return;
+
+   /* initialise machines + GRID_SIZE + THREAD_ID  + BLOCK_SIZE */
+   for (d = 0; d < bdepth; d++) {
+      for (h = 0; h < bheight; h++) {
+         for (w = 0; w < bwidth; w++) {
+            int idx = w + (h * bwidth) + (d * bheight * bwidth);
+            machines[idx] = tgsi_exec_machine_create(PIPE_SHADER_COMPUTE);
+
+            machines[idx]->LocalMem = local_mem;
+            machines[idx]->LocalMemSize = cs->shader.req_local_mem;
+            cs_prepare(cs, machines[idx],
+                       w, h, d,
+                       grid_size[0], grid_size[1], grid_size[2],
+                       bwidth, bheight, bdepth,
+                       (struct tgsi_sampler *)softpipe->tgsi.sampler[PIPE_SHADER_COMPUTE],
+                       (struct tgsi_image *)softpipe->tgsi.image[PIPE_SHADER_COMPUTE],
+                       (struct tgsi_buffer *)softpipe->tgsi.buffer[PIPE_SHADER_COMPUTE]);
+            tgsi_exec_set_constant_buffers(machines[idx], PIPE_MAX_CONSTANT_BUFFERS,
+                                           softpipe->mapped_constants[PIPE_SHADER_COMPUTE],
+                                           softpipe->const_buffer_size[PIPE_SHADER_COMPUTE]);
+         }
+      }
+   }
+
+   for (g_d = 0; g_d < grid_size[2]; g_d++) {
+      for (g_h = 0; g_h < grid_size[1]; g_h++) {
+         for (g_w = 0; g_w < grid_size[0]; g_w++) {
+            run_workgroup(cs, g_w, g_h, g_d, num_threads_in_group, machines);
+         }
+      }
+   }
+
+   for (i = 0; i < num_threads_in_group; i++) {
+      cs_delete(cs, machines[i]);
+      tgsi_exec_machine_destroy(machines[i]);
+   }
+
+   FREE(local_mem);
+   FREE(machines);
+}