drm/i915: debugfs: Add support for probing DP sink CRC.
This debugfs interface will allow intel-gpu-tools test case
to verify if screen has been updated properly on cases like PSR.
v2: Accepted all Daniel's suggestions:
* grab modeset lock
* loop over connector and check DPMS on
* return errors
* use _eDP1 suffix for easy future extension
* don't cache crc_supported neither latest crc
* return crc as a full array and read it at once with aux.
* use 0 to turn TEST_SINK off.
* split the drm_helpers definitions in another patch.
v3: Accepted 2 Damien's suggestion: remove h from printf hexa
and return ENODEV when eDP not present instead of EAGAIN.
v4: Accepted 2 Jani' s suggestion: 1 path for unlock and remove
_retry from aux read.
v5: removing last missing useless _retry (by Damien)
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Damien Lespiau <damien.lespiau@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index e37c7a0..389eabf 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -2922,6 +2922,35 @@
edp_panel_vdd_off(intel_dp, false);
}
+int intel_dp_sink_crc(struct intel_dp *intel_dp, u8 *crc)
+{
+ struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
+ struct drm_device *dev = intel_dig_port->base.base.dev;
+ struct intel_crtc *intel_crtc =
+ to_intel_crtc(intel_dig_port->base.base.crtc);
+ u8 buf[1];
+
+ if (!intel_dp_aux_native_read(intel_dp, DP_TEST_SINK_MISC, buf, 1))
+ return -EAGAIN;
+
+ if (!(buf[0] & DP_TEST_CRC_SUPPORTED))
+ return -ENOTTY;
+
+ if (!intel_dp_aux_native_write_1(intel_dp, DP_TEST_SINK,
+ DP_TEST_SINK_START))
+ return -EAGAIN;
+
+ /* Wait 2 vblanks to be sure we will have the correct CRC value */
+ intel_wait_for_vblank(dev, intel_crtc->pipe);
+ intel_wait_for_vblank(dev, intel_crtc->pipe);
+
+ if (!intel_dp_aux_native_read(intel_dp, DP_TEST_CRC_R_CR, crc, 6))
+ return -EAGAIN;
+
+ intel_dp_aux_native_write_1(intel_dp, DP_TEST_SINK, 0);
+ return 0;
+}
+
static bool
intel_dp_get_sink_irq(struct intel_dp *intel_dp, u8 *sink_irq_vector)
{