From d41cf9fb60cc4f2183daa4fd58fad72bf7e75f85 Mon Sep 17 00:00:00 2001 From: Kenneth Graunke Date: Wed, 12 Nov 2014 11:17:55 -0800 Subject: [PATCH] i965: Implement WaCsStallAtEveryFourthPipecontrol on IVB/BYT. According to the documentation, we need to do a CS stall on every fourth PIPE_CONTROL command to avoid GPU hangs. The kernel does a CS stall between batches, so we only need to count the PIPE_CONTROLs in our batches. v2: Get the generation check right (caught by Chris Wilson), combine the ++ with the check (suggested by Daniel Vetter). Signed-off-by: Kenneth Graunke Reviewed-by: Daniel Vetter --- src/mesa/drivers/dri/i965/brw_context.h | 2 ++ src/mesa/drivers/dri/i965/intel_batchbuffer.c | 32 +++++++++++++++++++ 2 files changed, 34 insertions(+) diff --git a/src/mesa/drivers/dri/i965/brw_context.h b/src/mesa/drivers/dri/i965/brw_context.h index fde41773018..c1787a8cf7f 100644 --- a/src/mesa/drivers/dri/i965/brw_context.h +++ b/src/mesa/drivers/dri/i965/brw_context.h @@ -868,6 +868,8 @@ struct intel_batchbuffer { enum brw_gpu_ring ring; bool needs_sol_reset; + uint8_t pipe_controls_since_last_cs_stall; + struct { uint16_t used; int reloc_count; diff --git a/src/mesa/drivers/dri/i965/intel_batchbuffer.c b/src/mesa/drivers/dri/i965/intel_batchbuffer.c index 2bd11d7a63e..193550bc2dd 100644 --- a/src/mesa/drivers/dri/i965/intel_batchbuffer.c +++ b/src/mesa/drivers/dri/i965/intel_batchbuffer.c @@ -81,6 +81,7 @@ intel_batchbuffer_reset(struct brw_context *brw) brw->batch.state_batch_offset = brw->batch.bo->size; brw->batch.used = 0; brw->batch.needs_sol_reset = false; + brw->batch.pipe_controls_since_last_cs_stall = 0; /* We don't know what ring the new batch will be sent to until we see the * first BEGIN_BATCH or BEGIN_BATCH_BLT. Mark it as unknown. @@ -433,6 +434,33 @@ gen8_add_cs_stall_workaround_bits(uint32_t *flags) *flags |= PIPE_CONTROL_STALL_AT_SCOREBOARD; } +/* Implement the WaCsStallAtEveryFourthPipecontrol workaround on IVB, BYT: + * + * "Every 4th PIPE_CONTROL command, not counting the PIPE_CONTROL with + * only read-cache-invalidate bit(s) set, must have a CS_STALL bit set." + * + * Note that the kernel does CS stalls between batches, so we only need + * to count them within a batch. + */ +static uint32_t +gen7_cs_stall_every_four_pipe_controls(struct brw_context *brw, uint32_t flags) +{ + if (brw->gen == 7 && !brw->is_haswell) { + if (flags & PIPE_CONTROL_CS_STALL) { + /* If we're doing a CS stall, reset the counter and carry on. */ + brw->batch.pipe_controls_since_last_cs_stall = 0; + return 0; + } + + /* If this is the fourth pipe control without a CS stall, do one now. */ + if (++brw->batch.pipe_controls_since_last_cs_stall == 4) { + brw->batch.pipe_controls_since_last_cs_stall = 0; + return PIPE_CONTROL_CS_STALL; + } + } + return 0; +} + /** * Emit a PIPE_CONTROL with various flushing flags. * @@ -454,6 +482,8 @@ brw_emit_pipe_control_flush(struct brw_context *brw, uint32_t flags) OUT_BATCH(0); ADVANCE_BATCH(); } else if (brw->gen >= 6) { + flags |= gen7_cs_stall_every_four_pipe_controls(brw, flags); + BEGIN_BATCH(5); OUT_BATCH(_3DSTATE_PIPE_CONTROL | (5 - 2)); OUT_BATCH(flags); @@ -496,6 +526,8 @@ brw_emit_pipe_control_write(struct brw_context *brw, uint32_t flags, OUT_BATCH(imm_upper); ADVANCE_BATCH(); } else if (brw->gen >= 6) { + flags |= gen7_cs_stall_every_four_pipe_controls(brw, flags); + /* PPGTT/GGTT is selected by DW2 bit 2 on Sandybridge, but DW1 bit 24 * on later platforms. We always use PPGTT on Gen7+. */ -- 2.30.2