From 6a5c86f48675d2ca0975d69e0899e72afaab29e5 Mon Sep 17 00:00:00 2001 From: Chad Versace Date: Mon, 23 Dec 2013 17:48:45 -0800 Subject: [PATCH] i965/gen6/blorp: Set need_workaround_flush at top of blorp MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Unconditionally set brw->need_workaround_flush at the top of gen6 blorp state emission. The art of emitting workaround flushes on Sandybridge is mysterious and not fully understood. Ken and I believe that intel_emit_post_sync_nonzero_flush() may be required when switching from regular drawing to blorp. This is an extra safety measure to prevent undiscovered difficult-to-diagnose gpu hangs. I verified that on ChromeOS, pre-patch, need_workaround_flush was not set at the top of blorp, as Paul expected. To verify, I inserted the following debug code at the top of gen6_blorp_exec(), restarted the ui, and inspected the logs in /var/log/ui. The abort gets triggered so early that the browser never appears on the display. static void gen6_blorp_exec(...) { if (!brw->need_workaround_flush) { fprintf(stderr, "chadv: %s:%d\n", __FILE__, __LINE__); abort(); } ... } CC: Kenneth Graunke CC: Stéphane Marchesin Reviewed-by: Paul Berry Signed-off-by: Chad Versace --- src/mesa/drivers/dri/i965/gen6_blorp.cpp | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/src/mesa/drivers/dri/i965/gen6_blorp.cpp b/src/mesa/drivers/dri/i965/gen6_blorp.cpp index 929d7b5a679..9db08401aa4 100644 --- a/src/mesa/drivers/dri/i965/gen6_blorp.cpp +++ b/src/mesa/drivers/dri/i965/gen6_blorp.cpp @@ -1023,7 +1023,6 @@ gen6_emit_hiz_workaround(struct brw_context *brw, enum gen6_hiz_op hiz_op) */ if (hiz_op == GEN6_HIZ_OP_DEPTH_RESOLVE || hiz_op == GEN6_HIZ_OP_HIZ_RESOLVE) { - brw->batch.need_workaround_flush = true; intel_emit_post_sync_nonzero_flush(brw); intel_emit_depth_stall_flushes(brw); } @@ -1051,6 +1050,9 @@ gen6_blorp_exec(struct brw_context *brw, uint32_t prog_offset = params->get_wm_prog(brw, &prog_data); + /* Emit workaround flushes when we switch from drawing to blorping. */ + brw->batch.need_workaround_flush = true; + gen6_emit_hiz_workaround(brw, params->hiz_op); gen6_emit_3dstate_multisample(brw, params->dst.num_samples); gen6_emit_3dstate_sample_mask(brw, -- 2.30.2