On Wed, 18 Apr 2018, Jani Nikula <jani.nikula@xxxxxxxxx> wrote: > From: Abhay Kumar <abhay.kumar@xxxxxxxxx> > > In GLK when the device boots with only 1366x768 panel without audio, HDA > codec doesn't come up. In this case, the CDCLK is less than twice the > BCLK. Even though audio isn't being enabled, having a too low CDCLK > leads to audio probe failing altogether. > > Require CDCLK to be at least twice the BLCK regardless of audio. This is > a minimal fix to improve things. Unfortunately, this a) leads to too > high CDCLK being used when audio is not used, and b) is still not enough > to fix audio probe when no outputs are connected at probe time. > > The proper fix would be to increase CDCLK dynamically from the audio > component hooks. > > v2: > - Address comment (Jani) > - New design approach > v3: - Typo fix on top of v1 > > v4 by Jani: rewrite commit message, add comment in code > > Cc: stable@xxxxxxxxxxxxxxx > Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@xxxxxxxxx> > Cc: Wenkai Du <wenkai.du@xxxxxxxxx> > Reviewed-by: Wenkai Du <wenkai.du@xxxxxxxxx> > Tested-by: Wenkai Du <wenkai.du@xxxxxxxxx> > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102937 > Signed-off-by: Abhay Kumar <abhay.kumar@xxxxxxxxx> > Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx> Pushed to dinq with Ville's Ack on another thread. BR, Jani. > --- > drivers/gpu/drm/i915/intel_cdclk.c | 16 ++++++++++++++-- > 1 file changed, 14 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/i915/intel_cdclk.c b/drivers/gpu/drm/i915/intel_cdclk.c > index fc8b2c6e3508..32d24c69da3c 100644 > --- a/drivers/gpu/drm/i915/intel_cdclk.c > +++ b/drivers/gpu/drm/i915/intel_cdclk.c > @@ -2140,10 +2140,22 @@ int intel_crtc_compute_min_cdclk(const struct intel_crtc_state *crtc_state) > } > } > > - /* According to BSpec, "The CD clock frequency must be at least twice > + /* > + * According to BSpec, "The CD clock frequency must be at least twice > * the frequency of the Azalia BCLK." and BCLK is 96 MHz by default. > + * > + * FIXME: Check the actual, not default, BCLK being used. > + * > + * FIXME: This does not depend on ->has_audio because the higher CDCLK > + * is required for audio probe, also when there are no audio capable > + * displays connected at probe time. This leads to unnecessarily high > + * CDCLK when audio is not required. > + * > + * FIXME: This limit is only applied when there are displays connected > + * at probe time. If we probe without displays, we'll still end up using > + * the platform minimum CDCLK, failing audio probe. > */ > - if (crtc_state->has_audio && INTEL_GEN(dev_priv) >= 9) > + if (INTEL_GEN(dev_priv) >= 9) > min_cdclk = max(2 * 96000, min_cdclk); > > /* -- Jani Nikula, Intel Open Source Technology Center _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
