i965/gen10+: Enable object level preemption.

Set bit when initializing context.

v3:
 - Always toggle preemption bool to false before enabling it for the
 first time, so the state gets emitted (Chris Wilson).
 - Emit end of pipe sync with PIPE_CONTROL_RENDER_TARGET_FLUSH (Ken)

Signed-off-by: Rafael Antognolli <[email protected]>
Reviewed-by: Kenneth Graunke <[email protected]>

4 files changed, 36 insertions, 1 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_context.h b/src/mesa/drivers/dri/i965/brw_context.h
index a5c49760175..66fe5b3a8a0 100644
--- a/src/mesa/drivers/dri/i965/brw_context.h
+++ b/src/mesa/drivers/dri/i965/brw_context.h
@@ -844,6 +844,8 @@ struct brw_context
 
    GLuint primitive; /**< Hardware primitive, such as _3DPRIM_TRILIST. */
 
+   bool object_preemption; /**< Object level preemption enabled. */
+
    GLenum reduced_primitive;
 
    /**
diff --git a/src/mesa/drivers/dri/i965/brw_defines.h b/src/mesa/drivers/dri/i965/brw_defines.h
index aec27a10ec4..5017c41ab24 100644
--- a/src/mesa/drivers/dri/i965/brw_defines.h
+++ b/src/mesa/drivers/dri/i965/brw_defines.h
@@ -1683,4 +1683,9 @@ enum brw_pixel_shader_coverage_mask_mode {
 # define HEADERLESS_MESSAGE_FOR_PREEMPTABLE_CONTEXTS        (1 << 5)
 # define HEADERLESS_MESSAGE_FOR_PREEMPTABLE_CONTEXTS_MASK   REG_MASK(1 << 5)
 
+#define CS_CHICKEN1                        0x2580 /* Gen9+ */
+# define GEN9_REPLAY_MODE_MIDBUFFER             (0 << 0)
+# define GEN9_REPLAY_MODE_MIDOBJECT             (1 << 0)
+# define GEN9_REPLAY_MODE_MASK                  REG_MASK(1 << 0)
+
 #endif
diff --git a/src/mesa/drivers/dri/i965/brw_state.h b/src/mesa/drivers/dri/i965/brw_state.h
index f6acf81b899..546d103d1a4 100644
--- a/src/mesa/drivers/dri/i965/brw_state.h
+++ b/src/mesa/drivers/dri/i965/brw_state.h
@@ -128,7 +128,7 @@ void brw_disk_cache_write_compute_program(struct brw_context *brw);
 void brw_disk_cache_write_render_programs(struct brw_context *brw);
 
 /***********************************************************************
- * brw_state.c
+ * brw_state_upload.c
  */
 void brw_upload_render_state(struct brw_context *brw);
 void brw_render_state_finished(struct brw_context *brw);
@@ -138,6 +138,7 @@ void brw_init_state(struct brw_context *brw);
 void brw_destroy_state(struct brw_context *brw);
 void brw_emit_select_pipeline(struct brw_context *brw,
                               enum brw_pipeline pipeline);
+void brw_enable_obj_preemption(struct brw_context *brw, bool enable);
 
 static inline void
 brw_select_pipeline(struct brw_context *brw, enum brw_pipeline pipeline)
diff --git a/src/mesa/drivers/dri/i965/brw_state_upload.c b/src/mesa/drivers/dri/i965/brw_state_upload.c
index 60b72bf4ab3..50049d325b3 100644
--- a/src/mesa/drivers/dri/i965/brw_state_upload.c
+++ b/src/mesa/drivers/dri/i965/brw_state_upload.c
@@ -45,6 +45,28 @@
 #include "brw_cs.h"
 #include "main/framebuffer.h"
 
+void
+brw_enable_obj_preemption(struct brw_context *brw, bool enable)
+{
+   const struct gen_device_info *devinfo = &brw->screen->devinfo;
+   assert(devinfo->gen >= 9);
+
+   if (enable == brw->object_preemption)
+      return;
+
+   /* A fixed function pipe flush is required before modifying this field */
+   brw_emit_end_of_pipe_sync(brw, PIPE_CONTROL_RENDER_TARGET_FLUSH);
+
+   bool replay_mode = enable ?
+      GEN9_REPLAY_MODE_MIDOBJECT : GEN9_REPLAY_MODE_MIDBUFFER;
+
+   /* enable object level preemption */
+   brw_load_register_imm32(brw, CS_CHICKEN1,
+                           replay_mode | GEN9_REPLAY_MODE_MASK);
+
+   brw->object_preemption = enable;
+}
+
 static void
 brw_upload_initial_gpu_state(struct brw_context *brw)
 {
@@ -160,6 +182,11 @@ brw_upload_initial_gpu_state(struct brw_context *brw)
          ADVANCE_BATCH();
       }
    }
+
+   brw->object_preemption = false;
+
+   if (devinfo->gen >= 10)
+      brw_enable_obj_preemption(brw, true);
 }
 
 static inline const struct brw_tracked_state *