I recently discovered this text in the BSpec. It seems wise to comply, though I haven't observed it to fix anything yet.
Fixes a regression in glean/fbo since 28cfa1fa213fe. NOTE: This is a candidate for stable release branches. Cc: Eric Anholt <e...@anholt.net> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=45221 Signed-off-by: Kenneth Graunke <kenn...@whitecape.org> --- src/mesa/drivers/dri/i965/gen7_urb.c | 2 + src/mesa/drivers/dri/i965/gen7_vs_state.c | 2 + src/mesa/drivers/dri/intel/intel_batchbuffer.c | 26 ++++++++++++++++++++++- src/mesa/drivers/dri/intel/intel_batchbuffer.h | 1 + 4 files changed, 29 insertions(+), 2 deletions(-) This also obsoletes Eric's uncommitted patch i965/gen7: Always allocate push constant space before uploading. as it fixes the same problem without such a large performance hit. My theory is that since 3DSTATE_PUSH_CONSTANT_ALLOC_VS is a non-pipelined command, emitting it at the top of upload_vs_state effectively served the same purpose (only a much harsher flush). diff --git a/src/mesa/drivers/dri/i965/gen7_urb.c b/src/mesa/drivers/dri/i965/gen7_urb.c index e6cf1eb..920c9fc 100644 --- a/src/mesa/drivers/dri/i965/gen7_urb.c +++ b/src/mesa/drivers/dri/i965/gen7_urb.c @@ -99,6 +99,8 @@ gen7_upload_urb(struct brw_context *brw) /* GS requirement */ assert(!brw->gs.prog_active); + gen7_emit_vs_workaround_flush(intel); + BEGIN_BATCH(2); OUT_BATCH(_3DSTATE_URB_VS << 16 | (2 - 2)); OUT_BATCH(brw->urb.nr_vs_entries | diff --git a/src/mesa/drivers/dri/i965/gen7_vs_state.c b/src/mesa/drivers/dri/i965/gen7_vs_state.c index 0746e6c..a3d652c 100644 --- a/src/mesa/drivers/dri/i965/gen7_vs_state.c +++ b/src/mesa/drivers/dri/i965/gen7_vs_state.c @@ -35,6 +35,8 @@ upload_vs_state(struct brw_context *brw) struct intel_context *intel = &brw->intel; uint32_t floating_point_mode = 0; + gen7_emit_vs_workaround_flush(intel); + BEGIN_BATCH(2); OUT_BATCH(_3DSTATE_BINDING_TABLE_POINTERS_VS << 16 | (2 - 2)); OUT_BATCH(brw->bind.bo_offset); diff --git a/src/mesa/drivers/dri/intel/intel_batchbuffer.c b/src/mesa/drivers/dri/intel/intel_batchbuffer.c index c58dee8..d10e008 100644 --- a/src/mesa/drivers/dri/intel/intel_batchbuffer.c +++ b/src/mesa/drivers/dri/intel/intel_batchbuffer.c @@ -56,13 +56,13 @@ intel_batchbuffer_init(struct intel_context *intel) { intel_batchbuffer_reset(intel); - if (intel->gen == 6) { + if (intel->gen >= 6) { /* We can't just use brw_state_batch to get a chunk of space for * the gen6 workaround because it involves actually writing to * the buffer, and the kernel doesn't let us write to the batch. */ intel->batch.workaround_bo = drm_intel_bo_alloc(intel->bufmgr, - "gen6 workaround", + "pipe_control workaround", 4096, 4096); } } @@ -394,6 +394,28 @@ intel_emit_depth_stall_flushes(struct intel_context *intel) } /** + * From the BSpec, volume 2a.03: VS Stage Input / State: + * "[DevIVB] A PIPE_CONTROL with Post-Sync Operation set to 1h and a depth + * stall needs to be sent just prior to any 3DSTATE_VS, 3DSTATE_URB_VS, + * 3DSTATE_CONSTANT_VS, 3DSTATE_BINDING_TABLE_POINTER_VS, + * 3DSTATE_SAMPLER_STATE_POINTER_VS command. Only one PIPE_CONTROL needs + * to be sent before any combination of VS associated 3DSTATE." + */ +void +gen7_emit_vs_workaround_flush(struct intel_context *intel) +{ + assert(intel->gen == 7); + + BEGIN_BATCH(4); + OUT_BATCH(_3DSTATE_PIPE_CONTROL); + OUT_BATCH(PIPE_CONTROL_DEPTH_STALL | PIPE_CONTROL_WRITE_IMMEDIATE); + OUT_RELOC(intel->batch.workaround_bo, + I915_GEM_DOMAIN_INSTRUCTION, I915_GEM_DOMAIN_INSTRUCTION, 0); + OUT_BATCH(0); /* write data */ + ADVANCE_BATCH(); +} + +/** * Emits a PIPE_CONTROL with a non-zero post-sync operation, for * implementing two workarounds on gen6. From section 1.4.7.1 * "PIPE_CONTROL" of the Sandy Bridge PRM volume 2 part 1: diff --git a/src/mesa/drivers/dri/intel/intel_batchbuffer.h b/src/mesa/drivers/dri/intel/intel_batchbuffer.h index e5e5bd4..751ec99 100644 --- a/src/mesa/drivers/dri/intel/intel_batchbuffer.h +++ b/src/mesa/drivers/dri/intel/intel_batchbuffer.h @@ -43,6 +43,7 @@ bool intel_batchbuffer_emit_reloc_fenced(struct intel_context *intel, void intel_batchbuffer_emit_mi_flush(struct intel_context *intel); void intel_emit_post_sync_nonzero_flush(struct intel_context *intel); void intel_emit_depth_stall_flushes(struct intel_context *intel); +void gen7_emit_vs_workaround_flush(struct intel_context *intel); static INLINE uint32_t float_as_int(float f) { -- 1.7.7.1 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
