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| author | Kai Vehmanen <kai.vehmanen@linux.intel.com> | 2019-12-31 17:00:07 +0300 |
|---|---|---|
| committer | Joonas Lahtinen <joonas.lahtinen@linux.intel.com> | 2020-01-07 13:50:00 +0300 |
| commit | f4b18892dca8e629e0ce192b233579505f8ed343 (patch) | |
| tree | 88ed7f31dde36a85f678c66dca8914f12fbb2200 /drivers/gpu | |
| parent | 1325008f5c8dbc84aa835d98af8447fa0569bc4d (diff) | |
| download | linux-f4b18892dca8e629e0ce192b233579505f8ed343.tar.xz | |
drm/i915: Limit audio CDCLK>=2*BCLK constraint back to GLK only
Revert changes done in commit f6ec9483091f ("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: f6ec9483091f ("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: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191231140007.31728-1-kai.vehmanen@linux.intel.com
(cherry picked from commit 1ee48a61aa57dbdbc3cd2808d8b28df40d938e44)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_audio.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_audio.c b/drivers/gpu/drm/i915/display/intel_audio.c index 85e6b2bbb34f..3a5ac13d5801 100644 --- a/drivers/gpu/drm/i915/display/intel_audio.c +++ b/drivers/gpu/drm/i915/display/intel_audio.c @@ -856,7 +856,7 @@ static unsigned long i915_audio_component_get_power(struct device *kdev) } /* Force CDCLK to 2*BCLK as long as we need audio powered. */ - if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv)) + if (IS_GEMINILAKE(dev_priv)) glk_force_audio_cdclk(dev_priv, true); if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv)) @@ -875,7 +875,7 @@ static void i915_audio_component_put_power(struct device *kdev, /* Stop forcing CDCLK to 2*BCLK if no need for audio to be powered. */ if (--dev_priv->audio_power_refcount == 0) - if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv)) + if (IS_GEMINILAKE(dev_priv)) glk_force_audio_cdclk(dev_priv, false); intel_display_power_put(dev_priv, POWER_DOMAIN_AUDIO, cookie); |