[PATCH 8/8] drm/i915/display: Prepare for vblank_delay for LRR

[Ankit Nautiyal <ankit.k.nautiyal@intel.com>]

Update allow_vblank_delay_fastset() to permit vblank delay adjustments
during with LRR when VRR TG is always active.

Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
---
 drivers/gpu/drm/i915/display/intel_display.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index cd499e58bed3..1426218c01d2 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -4958,9 +4958,15 @@ static bool allow_vblank_delay_fastset(const struct intel_crtc_state *old_crtc_s
 	 * Allow fastboot to fix up vblank delay (handled via LRR
 	 * codepaths), a bit dodgy as the registers aren't
 	 * double buffered but seems to be working more or less...
+	 *
+	 * Also allow this when the VRR timing generator is always on,
+	 * and optimized guardband is used. In such cases,
+	 * vblank delay may vary even without inherited state, but it's
+	 * still safe as VRR guardband is still same.
 	 */
-	return HAS_LRR(display) && old_crtc_state->inherited &&
-		!intel_crtc_has_type(old_crtc_state, INTEL_OUTPUT_DSI);
+	return HAS_LRR(display) &&
+	       (old_crtc_state->inherited || intel_vrr_always_use_vrr_tg(display)) &&
+	       !intel_crtc_has_type(old_crtc_state, INTEL_OUTPUT_DSI);
 }
 
 bool
-- 
2.45.2