[PATCH v8 02/10] drm/i915/vrr: Restrict CMRR enable condition to VRR-TG-default platforms

[Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>]

CMRR is currently advertised on all HAS_CMRR platforms, but it depends
on the VRR timing generator being the default timing generator, which
currently only applies to DISPLAY_VER >= 30.

Gate the CMRR enable condition and readout accordingly so CMRR is only
reported on supported platforms.

No functional change.

--v2:
- Create a separate function to check if CMRR possible

--v3:
- Simplify commit message (Chaitanya)
- Remove redundant outer parenthesis (Chaitanya)

Signed-off-by: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
Reviewed-by: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
---
 drivers/gpu/drm/i915/display/intel_vrr.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c
index 51e4f3309b8b..b0c9101e6ed3 100644
--- a/drivers/gpu/drm/i915/display/intel_vrr.c
+++ b/drivers/gpu/drm/i915/display/intel_vrr.c
@@ -187,15 +187,21 @@ int intel_vrr_vmax_vblank_start(const struct intel_crtc_state *crtc_state)
 	return intel_vrr_vmax_vtotal(crtc_state) - crtc_state->vrr.guardband;
 }
 
+static bool intel_vrr_cmrr_possible(const struct intel_crtc_state *crtc_state)
+{
+	struct intel_display *display = to_intel_display(crtc_state);
+
+	return HAS_CMRR(display) && intel_vrr_always_use_vrr_tg(display);
+}
+
 static bool
 is_cmrr_frac_required(struct intel_crtc_state *crtc_state)
 {
-	struct intel_display *display = to_intel_display(crtc_state);
 	int calculated_refresh_k, actual_refresh_k, pixel_clock_per_line;
 	struct drm_display_mode *adjusted_mode = &crtc_state->hw.adjusted_mode;
 
 	/* Avoid CMRR for now till we have VRR with fixed timings working */
-	if (!HAS_CMRR(display) || true)
+	if (!intel_vrr_cmrr_possible(crtc_state) || true)
 		return false;
 
 	actual_refresh_k =
@@ -1066,7 +1072,7 @@ void intel_vrr_get_config(struct intel_crtc_state *crtc_state)
 	trans_vrr_ctl = intel_de_read(display,
 				      TRANS_VRR_CTL(display, cpu_transcoder));
 
-	if (HAS_CMRR(display))
+	if (intel_vrr_cmrr_possible(crtc_state))
 		crtc_state->cmrr.enable = (trans_vrr_ctl & VRR_CTL_CMRR_ENABLE);
 
 	if (crtc_state->cmrr.enable) {
-- 
2.48.1