From: Francisco Jerez Date: Sun, 3 Jan 2016 03:05:48 +0000 (-0800) Subject: i965/gen4-5: Emit MI_FLUSH as required prior to switching pipelines. X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=635be1402c485b154ab1bf23e5448827364e70a5;p=mesa.git i965/gen4-5: Emit MI_FLUSH as required prior to switching pipelines. AFAIK brw_emit_select_pipeline() is only called once during context init on Gen4-5, at which point the pipeline is likely to be already idle so it may just happen to work by luck regardless of the MI_FLUSH. Reviewed-by: Matt Turner Reviewed-by: Kenneth Graunke --- diff --git a/src/mesa/drivers/dri/i965/brw_misc_state.c b/src/mesa/drivers/dri/i965/brw_misc_state.c index 95edbc9edcd..8335865b2d3 100644 --- a/src/mesa/drivers/dri/i965/brw_misc_state.c +++ b/src/mesa/drivers/dri/i965/brw_misc_state.c @@ -923,6 +923,19 @@ brw_emit_select_pipeline(struct brw_context *brw, enum brw_pipeline pipeline) PIPE_CONTROL_STATE_CACHE_INVALIDATE | PIPE_CONTROL_INSTRUCTION_INVALIDATE | PIPE_CONTROL_NO_WRITE); + + } else { + /* From "BXML » GT » MI » vol1a GPU Overview » [Instruction] + * PIPELINE_SELECT [DevBWR+]": + * + * Project: PRE-DEVSNB + * + * Software must ensure the current pipeline is flushed via an + * MI_FLUSH or PIPE_CONTROL prior to the execution of PIPELINE_SELECT. + */ + BEGIN_BATCH(1); + OUT_BATCH(MI_FLUSH); + ADVANCE_BATCH(); } /* Select the pipeline */