drm/i915/display: Add HW state readout for VRR

This functions gets the VRR config from the VRR registers
to match the crtc state variables for VRR.

v2:
* Rebase (Manasi)
* Use HAS_VRR (Jani N)

v3:
* Get pipeline_full, flipline (Ville)

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210122232647.22688-14-manasi.d.navare@intel.com

drivers/gpu/drm/i915/display/intel_display.c

@@ -8981,6 +8981,9 @@ static bool hsw_get_pipe_config(struct intel_crtc *crtc,
 		intel_get_transcoder_timings(crtc, pipe_config);
 	}
 
+	if (HAS_VRR(dev_priv))
+		intel_vrr_get_config(crtc, pipe_config);
+
 	intel_get_pipe_src_size(crtc, pipe_config);
 
 	if (IS_HASWELL(dev_priv)) {

drivers/gpu/drm/i915/display/intel_vrr.c

@@ -147,3 +147,23 @@ void intel_vrr_disable(const struct intel_crtc_state *old_crtc_state)
 	intel_de_write(dev_priv, TRANS_VRR_CTL(cpu_transcoder), 0);
 	intel_de_write(dev_priv, TRANS_PUSH(cpu_transcoder), 0);
 }
+
+void intel_vrr_get_config(struct intel_crtc *crtc,
+			  struct intel_crtc_state *crtc_state)
+{
+	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
+	u32 trans_vrr_ctl;
+
+	trans_vrr_ctl = intel_de_read(dev_priv, TRANS_VRR_CTL(cpu_transcoder));
+	crtc_state->vrr.enable = trans_vrr_ctl & VRR_CTL_VRR_ENABLE;
+	if (!crtc_state->vrr.enable)
+		return;
+
+	if (trans_vrr_ctl & VRR_CTL_PIPELINE_FULL_OVERRIDE)
+		crtc_state->vrr.pipeline_full = REG_FIELD_GET(VRR_CTL_PIPELINE_FULL_MASK, trans_vrr_ctl);
+	if (trans_vrr_ctl & VRR_CTL_FLIP_LINE_EN)
+		crtc_state->vrr.flipline = intel_de_read(dev_priv, TRANS_VRR_FLIPLINE(cpu_transcoder)) + 1;
+	crtc_state->vrr.vmax = intel_de_read(dev_priv, TRANS_VRR_VMAX(cpu_transcoder)) + 1;
+	crtc_state->vrr.vmin = intel_de_read(dev_priv, TRANS_VRR_VMIN(cpu_transcoder)) + 1;
+}

drivers/gpu/drm/i915/display/intel_vrr.h

@@ -15,6 +15,7 @@ struct intel_crtc;
 struct intel_crtc_state;
 struct intel_dp;
 struct intel_encoder;
+struct intel_crtc;
 
 bool intel_vrr_is_capable(struct drm_connector *connector);
 void intel_vrr_check_modeset(struct intel_atomic_state *state);
@@ -24,5 +25,7 @@ void intel_vrr_enable(struct intel_encoder *encoder,
 		      const struct intel_crtc_state *crtc_state);
 void intel_vrr_send_push(const struct intel_crtc_state *crtc_state);
 void intel_vrr_disable(const struct intel_crtc_state *old_crtc_state);
+void intel_vrr_get_config(struct intel_crtc *crtc,
+			  struct intel_crtc_state *crtc_state);
 
 #endif /* __INTEL_VRR_H__ */