[Mesa-dev] [PATCH 08/10] i965: Don't set interleave or complete on TCS EOT message.

[Kenneth Graunke]

Setting interleave on the TCS EOT message causes Ivybridge hardware to
GPU hang like crazy.  Individual tests would pass, but running even a
simple test like nop.shader_test in a loop would hang within 1-3 runs.
Adding sleep delays worked around the problem, somehow.

Interleave doesn't make much sense given that we only have one patch
URB handle, not two.  Complete doesn't seem useful either.

There's no reason to actually set those bits.  We were just being lazy.

Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
---
 src/mesa/drivers/dri/i965/brw_defines.h          |  1 +
 src/mesa/drivers/dri/i965/brw_shader.cpp         |  2 ++
 src/mesa/drivers/dri/i965/brw_vec4.cpp           |  1 +
 src/mesa/drivers/dri/i965/brw_vec4_generator.cpp | 36 ++++++++++++++++++++++--
 src/mesa/drivers/dri/i965/brw_vec4_tcs.cpp       |  6 ++--
 5 files changed, 41 insertions(+), 5 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_defines.h b/src/mesa/drivers/dri/i965/brw_defines.h
index d013748..10a6d39 100644
--- a/src/mesa/drivers/dri/i965/brw_defines.h
+++ b/src/mesa/drivers/dri/i965/brw_defines.h
@@ -1315,6 +1315,7 @@ enum opcode {
    TCS_OPCODE_CREATE_BARRIER_HEADER,
    TCS_OPCODE_SRC0_010_IS_ZERO,
    TCS_OPCODE_RELEASE_INPUT,
+   TCS_OPCODE_THREAD_END,
 
    TES_OPCODE_GET_PRIMITIVE_ID,
    TES_OPCODE_CREATE_INPUT_READ_HEADER,
diff --git a/src/mesa/drivers/dri/i965/brw_shader.cpp b/src/mesa/drivers/dri/i965/brw_shader.cpp
index f692bc2..d4b6410 100644
--- a/src/mesa/drivers/dri/i965/brw_shader.cpp
+++ b/src/mesa/drivers/dri/i965/brw_shader.cpp
@@ -572,6 +572,8 @@ brw_instruction_name(enum opcode op)
       return "tcs_src0<0,1,0>_is_zero";
    case TCS_OPCODE_RELEASE_INPUT:
       return "tcs_release_input";
+   case TCS_OPCODE_THREAD_END:
+      return "tcs_thread_end";
    case TES_OPCODE_CREATE_INPUT_READ_HEADER:
       return "tes_create_input_read_header";
    case TES_OPCODE_ADD_INDIRECT_URB_OFFSET:
diff --git a/src/mesa/drivers/dri/i965/brw_vec4.cpp b/src/mesa/drivers/dri/i965/brw_vec4.cpp
index f1c3d37..f0f18ca 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4.cpp
@@ -276,6 +276,7 @@ vec4_visitor::implied_mrf_writes(vec4_instruction *inst)
    case SHADER_OPCODE_POW:
       return 2;
    case VS_OPCODE_URB_WRITE:
+   case TCS_OPCODE_THREAD_END:
       return 1;
    case VS_OPCODE_PULL_CONSTANT_LOAD:
       return 2;
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_generator.cpp b/src/mesa/drivers/dri/i965/brw_vec4_generator.cpp
index cce2b4d..6b03a1c 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_generator.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_generator.cpp
@@ -758,8 +758,12 @@ generate_tcs_urb_write(struct brw_codegen *p,
                               true /* header */, false /* eot */);
    brw_inst_set_urb_opcode(devinfo, send, BRW_URB_OPCODE_WRITE_OWORD);
    brw_inst_set_urb_global_offset(devinfo, send, inst->offset);
-   brw_inst_set_urb_per_slot_offset(devinfo, send, 1);
-   brw_inst_set_urb_swizzle_control(devinfo, send, BRW_URB_SWIZZLE_INTERLEAVE);
+   if (inst->urb_write_flags & BRW_URB_WRITE_EOT) {
+      brw_inst_set_eot(devinfo, send, 1);
+   } else {
+      brw_inst_set_urb_per_slot_offset(devinfo, send, 1);
+      brw_inst_set_urb_swizzle_control(devinfo, send, BRW_URB_SWIZZLE_INTERLEAVE);
+   }
 
    /* what happens to swizzles? */
 }
@@ -969,6 +973,30 @@ generate_tcs_release_input(struct brw_codegen *p,
 }
 
 static void
+generate_tcs_thread_end(struct brw_codegen *p, vec4_instruction *inst)
+{
+   struct brw_reg header = brw_message_reg(inst->base_mrf);
+
+   brw_push_insn_state(p);
+   brw_set_default_access_mode(p, BRW_ALIGN_1);
+   brw_set_default_mask_control(p, BRW_MASK_DISABLE);
+   brw_MOV(p, header, brw_imm_ud(0));
+   brw_MOV(p, get_element_ud(header, 0),
+           retype(brw_vec1_grf(0, 0), BRW_REGISTER_TYPE_UD));
+   brw_pop_insn_state(p);
+
+   brw_urb_WRITE(p,
+                 brw_null_reg(), /* dest */
+                 inst->base_mrf, /* starting mrf reg nr */
+                 header,
+                 BRW_URB_WRITE_EOT | inst->urb_write_flags,
+                 inst->mlen,
+                 0,              /* response len */
+                 0,              /* urb destination offset */
+                 0);
+}
+
+static void
 generate_tes_get_primitive_id(struct brw_codegen *p, struct brw_reg dst)
 {
    brw_push_insn_state(p);
@@ -1892,6 +1920,10 @@ generate_code(struct brw_codegen *p,
          generate_tcs_release_input(p, dst, src[0], src[1]);
          break;
 
+      case TCS_OPCODE_THREAD_END:
+         generate_tcs_thread_end(p, inst);
+         break;
+
       case SHADER_OPCODE_BARRIER:
          brw_barrier(p, src[0]);
          brw_WAIT(p);
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_tcs.cpp b/src/mesa/drivers/dri/i965/brw_vec4_tcs.cpp
index 7693f09..fb6ca8e 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_tcs.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_tcs.cpp
@@ -203,9 +203,9 @@ vec4_tcs_visitor::emit_thread_end()
    if (unlikely(INTEL_DEBUG & DEBUG_SHADER_TIME))
       emit_shader_time_end();
 
-   inst = emit(VS_OPCODE_URB_WRITE);
-   inst->mlen = 1;   /* just the header, no data. */
-   inst->urb_write_flags = BRW_URB_WRITE_EOT_COMPLETE;
+   inst = emit(TCS_OPCODE_THREAD_END);
+   inst->base_mrf = 14;
+   inst->mlen = 1;
 }
 
 
-- 
2.6.4