[Intel-gfx] [PATCH] drm/i915/display: Fix shared dpll mismatch for bigjoiner slave

[Manasi Navare]

Currently when we do the HW state readout, we dont set the shared dpll to NULL
for the bigjoiner slave which should not have a DPLL assigned. So it has
some garbage while the HW state readout is NULL. So explicitly reset
the shared dpll for bigjoiner slave pipe.

Bug: https://gitlab.freedesktop.org/drm/intel/-/issues/3465
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Cc: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
Signed-off-by: Manasi Navare <manasi.d.navare at intel.com>
---
 drivers/gpu/drm/i915/display/intel_display.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 6be1b31af07b..606b9107d1cf 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -8971,8 +8971,10 @@ verify_crtc_state(struct intel_crtc *crtc,
 			"(expected %i, found %i)\n",
 			new_crtc_state->hw.active, crtc->active);
 
-	if (new_crtc_state->bigjoiner_slave)
+	if (new_crtc_state->bigjoiner_slave) {
+		pipe_config->shared_dpll = NULL;
 		master = new_crtc_state->bigjoiner_linked_crtc;
+	}
 
 	for_each_encoder_on_crtc(dev, &master->base, encoder) {
 		enum pipe pipe;
-- 
2.19.1