[Mesa-dev] [PATCH v2 2/4] i965/gen10: Implement WaForceRCPFEHangWorkaround

[Anuj Phogat]

V2: Add the check for Post Sync Operation.
    Update the workaround comment.

This workaround doesn't fix any of the piglit hangs we've seen
on CNL. But it might be fixing something we haven't tested yet.

Cc: Nanley Chery <nanley.g.chery at intel.com>
Signed-off-by: Anuj Phogat <anuj.phogat at gmail.com>
Reviewed-by: Rafael Antognolli <rafael.antognolli at intel.com>
---
 src/mesa/drivers/dri/i965/brw_pipe_control.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/src/mesa/drivers/dri/i965/brw_pipe_control.c b/src/mesa/drivers/dri/i965/brw_pipe_control.c
index 6ebe1443d5..b1975ce533 100644
--- a/src/mesa/drivers/dri/i965/brw_pipe_control.c
+++ b/src/mesa/drivers/dri/i965/brw_pipe_control.c
@@ -89,6 +89,24 @@ gen7_cs_stall_every_four_pipe_controls(struct brw_context *brw, uint32_t flags)
    return 0;
 }
 
+/* #1130 from gen10 workarounds page in h/w specs:
+ * "Enable Depth Stall on every Post Sync Op if Render target Cache Flush is
+ *  not enabled in same PIPE CONTROL and Enable Pixel score board stall if
+ *  Render target cache flush is enabled."
+ *
+ * Applicable to CNL B0 and C0 steppings only.
+ */
+static void
+gen10_add_rcpfe_workaround_bits(uint32_t *flags)
+{
+   if (*flags & PIPE_CONTROL_RENDER_TARGET_FLUSH)
+      *flags = *flags | PIPE_CONTROL_STALL_AT_SCOREBOARD;
+   else if ((*flags & PIPE_CONTROL_WRITE_IMMEDIATE) ||
+            (*flags & PIPE_CONTROL_WRITE_DEPTH_COUNT) ||
+            (*flags & PIPE_CONTROL_WRITE_TIMESTAMP))
+      *flags = *flags | PIPE_CONTROL_DEPTH_STALL;
+}
+
 static void
 brw_emit_pipe_control(struct brw_context *brw, uint32_t flags,
                       struct brw_bo *bo, uint32_t offset, uint64_t imm)
@@ -109,6 +127,9 @@ brw_emit_pipe_control(struct brw_context *brw, uint32_t flags,
          brw_emit_pipe_control_flush(brw, 0);
       }
 
+      if (devinfo->gen == 10)
+         gen10_add_rcpfe_workaround_bits(&flags);
+
       BEGIN_BATCH(6);
       OUT_BATCH(_3DSTATE_PIPE_CONTROL | (6 - 2));
       OUT_BATCH(flags);
-- 
2.13.5