From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Currently we only consider the relationship of the old and new CDCLK frequencies when determining whether to do the repgramming from intel_set_cdclk_pre_plane_update() or intel_set_cdclk_post_plane_update(). It is technically possible to have a situation where the CDCLK frequency is decreasing, but the voltage_level is increasing due a DDI port. In this case we should bump the voltage level already in intel_set_cdclk_pre_plane_update() (so that the voltage_level will have been increased by the time the port gets enabled), while leaving the CDCLK frequency unchanged (as active planes/etc. may still depend on it). We can then reduce the CDCLK frequency to its final value from intel_set_cdclk_post_plane_update(). In order to handle that correctly we shall construct a suitable amalgam of the old and new cdclk states in intel_set_cdclk_pre_plane_update(). And we can simply call intel_set_cdclk() unconditionally in both places as it will not do anything if nothing actually changes vs. the current hw state. Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/display/intel_cdclk.c | 25 +++++++++++++--------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_cdclk.c b/drivers/gpu/drm/i915/display/intel_cdclk.c index 49e2f09a796a..ce60d10666a2 100644 --- a/drivers/gpu/drm/i915/display/intel_cdclk.c +++ b/drivers/gpu/drm/i915/display/intel_cdclk.c @@ -2600,6 +2600,7 @@ intel_set_cdclk_pre_plane_update(struct intel_atomic_state *state) intel_atomic_get_old_cdclk_state(state); const struct intel_cdclk_state *new_cdclk_state = intel_atomic_get_new_cdclk_state(state); + struct intel_cdclk_config cdclk_config; if (!intel_cdclk_changed(&old_cdclk_state->actual, &new_cdclk_state->actual)) @@ -2608,12 +2609,19 @@ intel_set_cdclk_pre_plane_update(struct intel_atomic_state *state) if (IS_DG2(i915)) intel_cdclk_pcode_pre_notify(state); - if (old_cdclk_state->actual.cdclk <= new_cdclk_state->actual.cdclk) { - drm_WARN_ON(&i915->drm, !new_cdclk_state->base.changed); + if (new_cdclk_state->actual.cdclk >= old_cdclk_state->actual.cdclk) + cdclk_config = new_cdclk_state->actual; + else + cdclk_config = old_cdclk_state->actual; - intel_set_cdclk(i915, &new_cdclk_state->actual, - new_cdclk_state->pipe); - } + cdclk_config.voltage_level = max(new_cdclk_state->actual.voltage_level, + old_cdclk_state->actual.voltage_level); + + cdclk_config.joined_mbus = new_cdclk_state->actual.joined_mbus; + + drm_WARN_ON(&i915->drm, !new_cdclk_state->base.changed); + + intel_set_cdclk(i915, &cdclk_config, new_cdclk_state->pipe); } /** @@ -2639,12 +2647,9 @@ intel_set_cdclk_post_plane_update(struct intel_atomic_state *state) if (IS_DG2(i915)) intel_cdclk_pcode_post_notify(state); - if (old_cdclk_state->actual.cdclk > new_cdclk_state->actual.cdclk) { - drm_WARN_ON(&i915->drm, !new_cdclk_state->base.changed); + drm_WARN_ON(&i915->drm, !new_cdclk_state->base.changed); - intel_set_cdclk(i915, &new_cdclk_state->actual, - new_cdclk_state->pipe); - } + intel_set_cdclk(i915, &new_cdclk_state->actual, new_cdclk_state->pipe); } static int intel_pixel_rate_to_cdclk(const struct intel_crtc_state *crtc_state) -- 2.43.2