drm/i915/display: Fix shared dpll mismatch for bigjoiner slave

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@linux.intel.com>
Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Tested-by: Swati Sharma <swati2.sharma@intel.com>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210714223414.9849-1-manasi.d.navare@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 588b8ebe30207fe22c1c31e7a9b45a6d9d0a7e82..834d285b64773ca07d182875249db2b2e3f413af 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -9003,6 +9003,10 @@ verify_crtc_state(struct intel_crtc *crtc,
        if (!new_crtc_state->hw.active)
                return;
 
+       if (new_crtc_state->bigjoiner_slave)
+               /* No PLLs set for slave */
+               pipe_config->shared_dpll = NULL;
+
        intel_pipe_config_sanity_check(dev_priv, pipe_config);
 
        if (!intel_pipe_config_compare(new_crtc_state,