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Kai Vehmanen authored
Revert changes done in commit f6ec9483 ("drm/i915: extend audio CDCLK>=2*BCLK constraint to more platforms"). Audio drivers communicate with i915 over HDA bus multiple times during system boot-up and each of these transactions result in matching get_power/put_power calls to i915, and depending on the platform, a modeset change causing visible flicker. GLK is the only platform with minimum CDCLK significantly lower than BCLK, and thus for GLK setting a higher CDCLK is mandatory. For other platforms, minimum CDCLK is close but below 2*BCLK (e.g. on ICL, CDCLK=176.4kHz with BCLK=96kHz). Spec-wise the constraint should be set, but in practise no communication errors have been reported and the downside if set is the flicker observed at boot-time. Revert to old behaviour until better mechanism to manage probe-time clocks is available. The full CDCLK>=2*BCLK constraint is still enforced at pipe enable time in intel_crtc_compute_min_cdclk(). Bugzilla: https://gitlab.freedesktop.org/drm/intel/issues/913 Fixes: f6ec9483 ("drm/i915: extend audio CDCLK>=2*BCLK constraint to more platforms") Signed-off-by:
Kai Vehmanen <kai.vehmanen@linux.intel.com> Reviewed-by:
Matt Roper <matthew.d.roper@intel.com> Signed-off-by:
Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
f4b18892
