[Intel-gfx] [v2 6/6] drm/i915/fec: Disable FEC state.

[Anusha Srivatsa]

Set the suitable bits in DP_TP_CTL to stop
bit correction when DSC is disabled.

v2:
- rebased.
- Add additional check for compression state. (Gaurav)

v3: rebased.

Cc: Gaurav K Singh <gaurav.k.singh at intel.com>
Cc: Jani Nikula <jani.nikula at linux.intel.com>
Cc: Ville Syrjala <ville.syrjala at linux.intel.com>
Cc: Manasi Navare <manasi.d.navare at intel.com>
Signed-off-by: Anusha Srivatsa <anusha.srivatsa at intel.com>
---
 drivers/gpu/drm/i915/intel_ddi.c |  2 ++
 drivers/gpu/drm/i915/intel_dp.c  | 18 ++++++++++++++++++
 drivers/gpu/drm/i915/intel_drv.h |  2 ++
 3 files changed, 22 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index 67c013ea4d39..fefa92070b2d 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -3245,6 +3245,8 @@ static void intel_disable_ddi_dp(struct intel_encoder *encoder,
 	/* Disable the decompression in DP Sink */
 	intel_dp_sink_set_decompression_state(intel_dp, old_crtc_state,
 					      ~DP_DECOMPRESSION_EN);
+	/* Disable FEC in DP Sink */
+	intel_dp_disable_fec_state(intel_dp, old_crtc_state);
 }
 
 static void intel_disable_ddi_hdmi(struct intel_encoder *encoder,
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index b9f85502d9ff..1db1a738c85f 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -3044,6 +3044,24 @@ void intel_dp_enable_fec_state(struct intel_dp *intel_dp,
 		DRM_ERROR("Timed out waiting for FEC Enable Status\n");
 }
 
+void intel_dp_disable_fec_state(struct intel_dp *intel_dp,
+				const struct intel_crtc_state *crtc_state)
+{
+	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
+	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
+	enum port port = intel_dig_port->base.port;
+	u32 val;
+
+	if (crtc_state->dsc_params.compression_enable)
+		DRM_DEBUG_KMS("Compression still enabled\n");
+		return;
+
+	val = I915_READ(DP_TP_CTL(port));
+	val &= ~DP_TP_CTL_FEC_ENABLE;
+	I915_WRITE(DP_TP_CTL(port), val);
+	POSTING_READ(DP_TP_CTL(port));
+}
+
 /* If the sink supports it, try to set the power state appropriately */
 void intel_dp_sink_dpms(struct intel_dp *intel_dp, int mode)
 {
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index e51d612a9f42..0c2429f7cc35 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1713,6 +1713,8 @@ void intel_dp_sink_set_fec_ready(struct intel_dp *intel_dp,
 				 int state);
 void intel_dp_enable_fec_state(struct intel_dp *intel_dp,
 			       const struct intel_crtc_state *crtc_state);
+void intel_dp_disable_fec_state(struct intel_dp *intel_dp,
+				const struct intel_crtc_state *crtc_state);
 void intel_dp_encoder_reset(struct drm_encoder *encoder);
 void intel_dp_encoder_suspend(struct intel_encoder *intel_encoder);
 void intel_dp_encoder_destroy(struct drm_encoder *encoder);
-- 
2.17.1