[Mesa-dev] [PATCH 1/3] i965: Fix OACONTROL assertion failures on Ironlake.

[Kenneth Graunke]

I guarded half of the callers to start/stop_oa_counters with generation
checks, but missed the other half (which were added later).  OACONTROL
doesn't exist on Ironlake, so we better not write it.  Also, there's no
need---Ironlake's performance counters are always running.

This patch moves the generation checks into start/stop_oa_counters,
rather than requiring the caller to do them.

Fixes assertion failures in Piglit's AMD_performance_monitor/measure.

Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
Cc: Eric Anholt <eric at anholt.net>
---
 src/mesa/drivers/dri/i965/brw_performance_monitor.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

These are not candidates for 10.0 since AMD_performance_monitor support
landed after the branch point.  They're bug fixes for master only.

diff --git a/src/mesa/drivers/dri/i965/brw_performance_monitor.c b/src/mesa/drivers/dri/i965/brw_performance_monitor.c
index 9bddd8e..ff3cb97 100644
--- a/src/mesa/drivers/dri/i965/brw_performance_monitor.c
+++ b/src/mesa/drivers/dri/i965/brw_performance_monitor.c
@@ -642,6 +642,8 @@ start_oa_counters(struct brw_context *brw)
 
    /* Pick the counter format which gives us all the counters. */
    switch (brw->gen) {
+   case 5:
+      return; /* Ironlake counters are always running. */
    case 6:
       counter_format = 1; /* 0b001 */
       break;
@@ -667,6 +669,10 @@ start_oa_counters(struct brw_context *brw)
 static void
 stop_oa_counters(struct brw_context *brw)
 {
+   /* Ironlake counters never stop. */
+   if (brw->gen == 5)
+      return;
+
    BEGIN_BATCH(3);
    OUT_BATCH(MI_LOAD_REGISTER_IMM | (3 - 2));
    OUT_BATCH(OACONTROL);
@@ -1367,8 +1373,7 @@ brw_perf_monitor_new_batch(struct brw_context *brw)
    if (brw->perfmon.oa_users == 0)
       return;
 
-   if (brw->gen >= 6)
-      start_oa_counters(brw);
+   start_oa_counters(brw);
 
    /* Make sure bookend_bo has enough space for a pair of snapshots.
     * If not, "wrap" the BO: gather up any results so far, and start from
@@ -1405,8 +1410,7 @@ brw_perf_monitor_finish_batch(struct brw_context *brw)
 
    emit_bookend_snapshot(brw);
 
-   if (brw->gen >= 6)
-      stop_oa_counters(brw);
+   stop_oa_counters(brw);
 }
 
 /******************************************************************************/
-- 
1.8.4.2