> -----Original Message-----
> From: Hogander, Jouni <jouni.hogander@xxxxxxxxx>
> Sent: Monday, December 9, 2024 5:29 PM
> To: Manna, Animesh <animesh.manna@xxxxxxxxx>; intel-
> gfx@xxxxxxxxxxxxxxxxxxxxx
> Cc: Nikula, Jani <jani.nikula@xxxxxxxxx>; B, Jeevan <jeevan.b@xxxxxxxxx>
> Subject: Re: [PATCH v2 1/2] drm/i915/lobf: Add lobf enablement in post
> plane update
>
> On Mon, 2024-12-09 at 11:54 +0000, Manna, Animesh wrote:
> >
> >
> > > -----Original Message-----
> > > From: Hogander, Jouni <jouni.hogander@xxxxxxxxx>
> > > Sent: Monday, December 9, 2024 5:04 PM
> > > To: Manna, Animesh <animesh.manna@xxxxxxxxx>; intel-
> > > gfx@xxxxxxxxxxxxxxxxxxxxx
> > > Cc: Nikula, Jani <jani.nikula@xxxxxxxxx>; B, Jeevan
> > > <jeevan.b@xxxxxxxxx>
> > > Subject: Re: [PATCH v2 1/2] drm/i915/lobf: Add lobf enablement in
> > > post plane update
> > >
> > > On Mon, 2024-12-09 at 11:19 +0000, Manna, Animesh wrote:
> > > >
> > > >
> > > > > -----Original Message-----
> > > > > From: Hogander, Jouni <jouni.hogander@xxxxxxxxx>
> > > > > Sent: Monday, December 9, 2024 2:06 PM
> > > > > To: Manna, Animesh <animesh.manna@xxxxxxxxx>; intel-
> > > > > gfx@xxxxxxxxxxxxxxxxxxxxx
> > > > > Cc: Nikula, Jani <jani.nikula@xxxxxxxxx>; B, Jeevan
> > > > > <jeevan.b@xxxxxxxxx>
> > > > > Subject: Re: [PATCH v2 1/2] drm/i915/lobf: Add lobf enablement
> > > > > in post plane update
> > > > >
> > > > > On Wed, 2024-12-04 at 15:33 +0530, Animesh Manna wrote:
> > > > > > Enablement of LOBF is added in post plane update whenever
> > > > > > has_lobf flag is set. As LOBF can be enabled in non-psr case
> > > > > > as well so adding in post plane update. There is no change of
> > > > > > configuring alpm with psr path.
> > > > > >
> > > > > > v1: Initial version.
> > > > > > v2: Use encoder-mask to find the associated encoder from
> > > > > > crtc-
> > > > > > state.
> > > > > > [Jani]
> > > > > >
> > > > > > Signed-off-by: Animesh Manna <animesh.manna@xxxxxxxxx>
> > > > > > ---
> > > > > > drivers/gpu/drm/i915/display/intel_alpm.c | 25
> > > > > > ++++++++++++++++++++
> > > > > > drivers/gpu/drm/i915/display/intel_alpm.h | 4 ++++
> > > > > > drivers/gpu/drm/i915/display/intel_display.c | 3 +++
> > > > > > 3 files changed, 32 insertions(+)
> > > > > >
> > > > > > diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c
> > > > > > b/drivers/gpu/drm/i915/display/intel_alpm.c
> > > > > > index 55f3ae1e68c9..75063342a100 100644
> > > > > > --- a/drivers/gpu/drm/i915/display/intel_alpm.c
> > > > > > +++ b/drivers/gpu/drm/i915/display/intel_alpm.c
> > > > > > @@ -367,6 +367,31 @@ void intel_alpm_configure(struct intel_dp
> > > > > > *intel_dp,
> > > > > > lnl_alpm_configure(intel_dp, crtc_state);
> > > > > > }
> > > > > >
> > > > > > +void intel_alpm_post_plane_update(struct intel_atomic_state
> > > > > > *state,
> > > > > > + struct intel_crtc *crtc) {
> > > > > > + struct intel_display *display =
> > > > > > to_intel_display(state);
> > > > > > + const struct intel_crtc_state *crtc_state =
> > > > > > + intel_atomic_get_new_crtc_state(state, crtc);
> > > > > > + struct intel_encoder *encoder;
> > > > > > +
> > > > > > + if (!crtc_state->has_lobf)
> > > > > > + return;
> > > > > > +
> > > > > > + for_each_intel_encoder_mask(display->drm, encoder,
> > > > > > + crtc_state-
> > > > > > > uapi.encoder_mask) {
> > > > > > + struct intel_dp *intel_dp;
> > > > > > +
> > > > > > + if (!intel_encoder_is_dp(encoder))
> > > > > > + continue;
> > > > > > +
> > > > > > + intel_dp = enc_to_intel_dp(encoder);
> > > > > > +
> > > > > > + if (intel_dp_is_edp(intel_dp))
> > > > > > + intel_alpm_configure(intel_dp,
> > > > > > crtc_state);
> > > > >
> > > > > This is reconfiguring lobf even if it's already configured? Is
> > > > > that wanted?
> > > >
> > > > has_psr and has_lobf are mutually exclusive, so alpm_configure()
> > > > will be called once.
> > >
> > > has_psr is unrelated. Consider e.g. case where xe.enable_psr=0 is in
> > > bootcmd. has_psr is always false. ALPM_CTL is written with lobf
> > > enabled on every commit if has_lobf is true.
> >
> > Currently VRR fixed refresh mode check is not added in this patch
> > series which can take care of resetting the has_lobf flag as well,
> > thanks for catching, will add in next version.
> > Hope with the above change the below comments will be addressed.
>
> Please note that it is not about just resetting the flag. Someone has to reset
> lobf enable bit in ALPM_CTL as well.
Agree, will add a check for (old_crtc_state->has_lobf && !new_crtc_state->has_lobf) to clear the bitfield of ALPM_CTL.
Regards,
Animesh
>
> BR,
>
> Jouni Högander
>
> >
> > Regards,
> > Animesh
> >
> > >
> > > Another thing here is that lobf is never disabled after it gets
> > > enabled?
> > >
> > > Please also review cases where lobf needs to be disabled. E.g.
> > > refresh rate
> > > change. See bspec 71041.
> > >
> > > BR,
> > >
> > > Jouni Högander
> > > >
> > > > Regards,
> > > > Animesh
> > > >
> > > > >
> > > > > BR,
> > > > >
> > > > > Jouni Högander
> > > > > > + }
> > > > > > +}
> > > > > > +
> > > > > > static int i915_edp_lobf_info_show(struct seq_file *m, void
> > > > > > *data)
> > > > > > {
> > > > > > struct intel_connector *connector = m->private; diff
> > > > > > --
> > > > > > git a/drivers/gpu/drm/i915/display/intel_alpm.h
> > > > > > b/drivers/gpu/drm/i915/display/intel_alpm.h
> > > > > > index 8c409b10dce6..2f862b0476a8 100644
> > > > > > --- a/drivers/gpu/drm/i915/display/intel_alpm.h
> > > > > > +++ b/drivers/gpu/drm/i915/display/intel_alpm.h
> > > > > > @@ -12,6 +12,8 @@ struct intel_dp;
> > > > > > struct intel_crtc_state;
> > > > > > struct drm_connector_state;
> > > > > > struct intel_connector;
> > > > > > +struct intel_atomic_state;
> > > > > > +struct intel_crtc;
> > > > > >
> > > > > > void intel_alpm_init_dpcd(struct intel_dp *intel_dp);
> > > > > > bool intel_alpm_compute_params(struct intel_dp *intel_dp, @@
> > > > > > -
> > > > > > 21,6
> > > > > > +23,8 @@ void intel_alpm_lobf_compute_config(struct intel_dp
> > > > > > *intel_dp,
> > > > > > struct drm_connector_state
> > > > > > *conn_state);
> > > > > > void intel_alpm_configure(struct intel_dp *intel_dp,
> > > > > > const struct intel_crtc_state
> > > > > > *crtc_state);
> > > > > > +void intel_alpm_post_plane_update(struct intel_atomic_state
> > > > > > *state,
> > > > > > + struct intel_crtc *crtc);
> > > > > > void intel_alpm_lobf_debugfs_add(struct intel_connector
> > > > > > *connector);
> > > > > > bool intel_alpm_aux_wake_supported(struct intel_dp
> > > > > > *intel_dp);
> > > > > > bool intel_alpm_aux_less_wake_supported(struct intel_dp
> > > > > > *intel_dp); diff --git
> > > > > > a/drivers/gpu/drm/i915/display/intel_display.c
> > > > > > b/drivers/gpu/drm/i915/display/intel_display.c
> > > > > > index 4805bf682d43..ffd96b187e5e 100644
> > > > > > --- a/drivers/gpu/drm/i915/display/intel_display.c
> > > > > > +++ b/drivers/gpu/drm/i915/display/intel_display.c
> > > > > > @@ -55,6 +55,7 @@
> > > > > > #include "i9xx_plane.h"
> > > > > > #include "i9xx_plane_regs.h"
> > > > > > #include "i9xx_wm.h"
> > > > > > +#include "intel_alpm.h"
> > > > > > #include "intel_atomic.h"
> > > > > > #include "intel_atomic_plane.h"
> > > > > > #include "intel_audio.h"
> > > > > > @@ -1190,6 +1191,8 @@ static void
> > > > > > intel_post_plane_update(struct intel_atomic_state *state,
> > > > > >
> > > > > > intel_psr_post_plane_update(state, crtc);
> > > > > >
> > > > > > + intel_alpm_post_plane_update(state, crtc);
> > > > > > +
> > > > > > intel_frontbuffer_flip(dev_priv, new_crtc_state-
> > > > > > > fb_bits);
> > > > > >
> > > > > > if (new_crtc_state->update_wm_post && new_crtc_state-
> > > > > > > hw.active)
> > > >
> >
