[Intel-gfx] [PATCH v2 2/3] drm/i915/dp: Fix sink-crc reads.

[Ville Syrjälä]

On Wed, Apr 25, 2018 at 02:57:57PM -0700, Dhinakaran Pandiyan wrote:
> Sink crc is calculated by the sink for static frames irrespective of
> what the driver sets in TEST_SINK_START dpcd. Since PSR is the only use
> case for sink crc, we don't really need the sink_crc_{start, stop} code.
> 
> The second problem with the current implementation is vblank waits.
> Enabling vblank interrupts triggers PSR exit, which means we aren't
> really reading the correct CRC values for PSR tests. vblank waits are
> replaced by delays.
> 
> With the changes made in this patch, sink CRC is available only for
> static frames. I have tested this on a SKL laptop with PSR panel.
> 
> v2: Use refresh rate to calculate frame time.
> 
> Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_debugfs.c |   4 +-
>  drivers/gpu/drm/i915/intel_dp.c     | 115 +++++-------------------------------
>  drivers/gpu/drm/i915/intel_drv.h    |   3 +-
>  3 files changed, 18 insertions(+), 104 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
> index 2f05f5262bba..e4ba6527c16e 100644
> --- a/drivers/gpu/drm/i915/i915_debugfs.c
> +++ b/drivers/gpu/drm/i915/i915_debugfs.c
> @@ -2749,6 +2749,7 @@ static int i915_sink_crc(struct seq_file *m, void *data)
>  		struct drm_crtc *crtc;
>  		struct drm_connector_state *state;
>  		struct intel_crtc_state *crtc_state;
> +		int vrefresh;
>  
>  		if (connector->base.connector_type != DRM_MODE_CONNECTOR_eDP)
>  			continue;
> @@ -2783,8 +2784,9 @@ static int i915_sink_crc(struct seq_file *m, void *data)
>  		}
>  
>  		intel_dp = enc_to_intel_dp(state->best_encoder);
> +		vrefresh = crtc_state->base.adjusted_mode.vrefresh;

Hmm. Is vrefresh always populated correctly for us?

-- 
Ville Syrjälä
Intel