[PATCH v2 10/14] drm/i915: Use old mbus_join value when increasing CDCLK

[Ville Syrjala]

From: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>

In order to make sure we are not breaking the proper sequence
let's do updates step by step and don't change MBUS join value
during MDCLK/CDCLK programming stage.
MBUS join programming would be taken care by pre/post ddb hooks.

v2: - Reworded comment about using old mbus_join value in
      intel_set_cdclk(Ville Syrjälä)

Reviewed-by: Uma Shankar <uma.shankar at intel.com>
Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>
[v3: vsyrjala: rebase on top of cdclk changes, reword a bit more]
Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_cdclk.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_cdclk.c b/drivers/gpu/drm/i915/display/intel_cdclk.c
index ed8d9ee094b8..e0c69d85e733 100644
--- a/drivers/gpu/drm/i915/display/intel_cdclk.c
+++ b/drivers/gpu/drm/i915/display/intel_cdclk.c
@@ -2617,6 +2617,12 @@ intel_set_cdclk_pre_plane_update(struct intel_atomic_state *state)
 						 old_cdclk_state->actual.voltage_level);
 	}
 
+	/*
+	 * mbus joining will be changed later by
+	 * intel_dbuf_mbus_{pre,post}_ddb_update()
+	 */
+	cdclk_config.joined_mbus = old_cdclk_state->actual.joined_mbus;
+
 	drm_WARN_ON(&i915->drm, !new_cdclk_state->base.changed);
 
 	intel_set_cdclk(i915, &cdclk_config, pipe,
-- 
2.43.2