Whenever DMC firmware put the HW into DC State a bunch
of registers including this perf counter is reset to 0 and
never restored.

So, even with PSR active and working we could still read
"Performance_Counter: 0" what will misslead people to believe
PSR is broken.

So, it is better to remove this counter information while
we don't have a better way to track PSR residency.

Signed-off-by: Rodrigo Vivi <rodrigo.v...@intel.com>
---
 drivers/gpu/drm/i915/i915_debugfs.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c 
b/drivers/gpu/drm/i915/i915_debugfs.c
index 038d5c6..71e1666 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -2580,8 +2580,11 @@ static int i915_edp_psr_status(struct seq_file *m, void 
*data)
                }
        seq_puts(m, "\n");
 
-       /* CHV PSR has no kind of performance counter */
-       if (HAS_DDI(dev)) {
+       /*
+        * VLV/CHV PSR has no kind of performance counter
+        * SKL+ Perf counter is reset to 0 everytime DC state is entered
+        */
+       if (IS_HASWELL(dev) || IS_BROADWELL(dev)) {
                psrperf = I915_READ(EDP_PSR_PERF_CNT) &
                        EDP_PSR_PERF_CNT_MASK;
 
-- 
2.4.3

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/intel-gfx

Reply via email to