Re: [v4,01/14] drm/i915: Fix PIPEDMC disabling for a bigjoiner configuration

[Imre Deak <imre.deak@intel.com>]

On Tue, May 30, 2023 at 01:49:07PM +0000, Rudi Heitbaum wrote:
Hi Rudi,

Could you open a ticket at
https://gitlab.freedesktop.org/drm/intel/-/issues/new

attaching a dmesg log after booting with drm.debug=0xe, with the
messages from boot-up until the issue happens?

Thanks,
Imre

> Hi Imre/Dave,
> 
> Ref: [v4,01/14] drm/i915: Fix PIPEDMC disabling for a bigjoiner configuration
>      [git pull] drm fixes for 6.4-rc4
>      drm-fixes-2023-05-26:
>      drm fixes for 6.4-rc4
> 
> This patch has caused a regression between 6.4-rc3 and 6.4-rc4. Other
> tested kernels include 6.3.4 work fine. Dropping the patch allows the decode
> playback of media via Kodi. Without dropping the patch - the media
> starts and stutters then ceases to play.
> 
> There is an additional issue that 6.4-rc4 audio playback is also failing
> (where 6.4-rc3 was fine), I have not yet tracked this down.
> 
> This is all on:
> DMI: Intel(R) Client Systems NUC12WSKi7/NUC12WSBi7, BIOS WSADL357.0087.2023.0306.1931 03/06/2023
> 12th Gen Intel(R) Core(TM) i7-1260P (family: 0x6, model: 0x9a, stepping: 0x3)
> microcode: updated early: 0x429 -> 0x42a, date = 2023-02-14
> 
> Regards
> 
> Rudi
> 
> On Wed, May 10, 2023 at 01:31:18PM +0300, Imre Deak wrote:
> > For a bigjoiner configuration display->crtc_disable() will be called
> > first for the slave CRTCs and then for the master CRTC. However slave
> > CRTCs will be actually disabled only after the master CRTC is disabled
> > (from the encoder disable hooks called with the master CRTC state).
> > Hence the slave PIPEDMCs can be disabled only after the master CRTC is
> > disabled, make this so.
> > 
> > intel_encoders_post_pll_disable() must be called only for the master
> > CRTC, as for the other two encoder disable hooks. While at it fix this
> > up as well. This didn't cause a problem, since
> > intel_encoders_post_pll_disable() will call the corresponding hook only
> > for an encoder/connector connected to the given CRTC, however slave
> > CRTCs will have no associated encoder/connector.
> > 
> > Fixes: 3af2ff0840be ("drm/i915: Enable a PIPEDMC whenever its corresponding pipe is enabled")
> > Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> > Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > Signed-off-by: Imre Deak <imre.deak@intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_display.c | 12 ++++++++++--
> >  1 file changed, 10 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> > index 1d5d42a408035..116fa52290b84 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display.c
> > +++ b/drivers/gpu/drm/i915/display/intel_display.c
> > @@ -1702,9 +1702,17 @@ static void hsw_crtc_disable(struct intel_atomic_state *state,
> >  
> >  	intel_disable_shared_dpll(old_crtc_state);
> >  
> > -	intel_encoders_post_pll_disable(state, crtc);
> > +	if (!intel_crtc_is_bigjoiner_slave(old_crtc_state)) {
> > +		struct intel_crtc *slave_crtc;
> > +
> > +		intel_encoders_post_pll_disable(state, crtc);
> >  
> > -	intel_dmc_disable_pipe(i915, crtc->pipe);
> > +		intel_dmc_disable_pipe(i915, crtc->pipe);
> > +
> > +		for_each_intel_crtc_in_pipe_mask(&i915->drm, slave_crtc,
> > +						 intel_crtc_bigjoiner_slave_pipes(old_crtc_state))
> > +			intel_dmc_disable_pipe(i915, slave_crtc->pipe);
> > +	}
> >  }
> >  
> >  static void i9xx_pfit_enable(const struct intel_crtc_state *crtc_state)