> -----Original Message-----
> From: Hogander, Jouni <jouni.hogander@xxxxxxxxx>
> Sent: Monday, April 15, 2024 3:36 PM
> To: Manna, Animesh <animesh.manna@xxxxxxxxx>; intel-
> gfx@xxxxxxxxxxxxxxxxxxxxx
> Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx; Murthy, Arun R
> <arun.r.murthy@xxxxxxxxx>; Nikula, Jani <jani.nikula@xxxxxxxxx>
> Subject: Re: [PATCH v2 4/6] drm/i915/alpm: Add compute config for lobf
>
> On Fri, 2024-04-12 at 21:22 +0530, Animesh Manna wrote:
> > Link Off Between Active Frames, is a new feature for eDP that allows
> > the panel to go to lower power state after transmission of data. This
> > is a feature on top of ALPM, AS SDP.
> > Add compute config during atomic-check phase.
> >
> > v1: RFC version.
> > v2: Add separate flag for auxless-alpm. [Jani]
> >
> > Signed-off-by: Animesh Manna <animesh.manna@xxxxxxxxx>
> > ---
> > drivers/gpu/drm/i915/display/intel_alpm.c | 44
> > +++++++++++++++++++
> > drivers/gpu/drm/i915/display/intel_alpm.h | 5 +++
> > .../drm/i915/display/intel_display_types.h | 4 ++
> > drivers/gpu/drm/i915/display/intel_dp.c | 5 +++
> > 4 files changed, 58 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c
> > b/drivers/gpu/drm/i915/display/intel_alpm.c
> > index 13bac3e8c8fa..699f2f051766 100644
> > --- a/drivers/gpu/drm/i915/display/intel_alpm.c
> > +++ b/drivers/gpu/drm/i915/display/intel_alpm.c
> > @@ -11,6 +11,16 @@
> > #include "intel_dp_aux.h"
> > #include "intel_psr_regs.h"
> >
> > +bool intel_dp_get_aux_less_alpm_status(struct intel_dp *intel_dp) {
> > + u8 alpm_caps = 0;
> > +
> > + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_RECEIVER_ALPM_CAP,
> > + &alpm_caps) != 1)
> > + return false;
> > + return alpm_caps & DP_ALPM_AUX_LESS_CAP; }
> > +
> > /*
> > * See Bspec: 71632 for the table
> > *
> > @@ -242,6 +252,40 @@ bool intel_alpm_compute_params(struct intel_dp
> > *intel_dp,
> > return true;
> > }
> >
> > +void intel_alpm_compute_lobf_config(struct intel_dp *intel_dp,
> > + struct intel_crtc_state
> > *crtc_state,
> > + struct drm_connector_state
> > *conn_state)
> > +{
> > + struct drm_display_mode *adjusted_mode = &crtc_state-
> > >hw.adjusted_mode;
> > + int waketime_in_lines, first_sdp_position;
> > + int context_latency, guardband;
> > +
> > + intel_dp->lobf_supported = false;
> > +
> > + if (!intel_dp_is_edp(intel_dp))
> > + return;
> > +
> > + if (!intel_dp_as_sdp_supported(intel_dp))
> > + return;
> > +
> > + if (crtc_state->has_psr2 || crtc_state->has_panel_replay)
> > + return;
>
> LOBF is not supported with PSR1? I think checking crtc_state->has_psr is
> enough. That covers PSR1/2 and Panel Replay.
Ok.
>
> > +
> > + if (intel_alpm_compute_params(intel_dp, crtc_state)) {
> > + context_latency = adjusted_mode->crtc_vblank_start -
> > adjusted_mode->crtc_vdisplay;
> > + guardband = adjusted_mode->crtc_vtotal -
> > + adjusted_mode->crtc_vdisplay -
> > context_latency;
> > + first_sdp_position = adjusted_mode->crtc_vtotal -
> > adjusted_mode->crtc_vsync_start;
> > + if (intel_dp->alpm_parameters.auxless_alpm_supported)
> > + waketime_in_lines = intel_dp-
> > >alpm_parameters.io_wake_lines;
> > + else
> > + waketime_in_lines = intel_dp-
> > >alpm_parameters.fast_wake_lines;
> > +
> > + if ((context_latency + guardband) >
> > (first_sdp_position + waketime_in_lines))
> > + intel_dp->lobf_supported = true;
> > + }
>
> You are not checking display version here. This is supported only on LNL and
> onwards.
Sure will add, thought as-sdp-support will take care, but it has display_ver >= 13.
>
> > +}
> > +
> > static void lnl_alpm_configure(struct intel_dp *intel_dp)
> > {
> > struct drm_i915_private *dev_priv = dp_to_i915(intel_dp); diff
> > --git a/drivers/gpu/drm/i915/display/intel_alpm.h
> > b/drivers/gpu/drm/i915/display/intel_alpm.h
> > index c45d078e5a6b..c341d2c2b7f7 100644
> > --- a/drivers/gpu/drm/i915/display/intel_alpm.h
> > +++ b/drivers/gpu/drm/i915/display/intel_alpm.h
> > @@ -10,9 +10,14 @@
> >
> > struct intel_dp;
> > struct intel_crtc_state;
> > +struct drm_connector_state;
> >
> > +bool intel_dp_get_aux_less_alpm_status(struct intel_dp *intel_dp);
> > bool intel_alpm_compute_params(struct intel_dp *intel_dp,
> > struct intel_crtc_state *crtc_state);
> > +void intel_alpm_compute_lobf_config(struct intel_dp *intel_dp,
> > + struct intel_crtc_state
> > *crtc_state,
> > + struct drm_connector_state
> > *conn_state);
> > void intel_alpm_configure(struct intel_dp *intel_dp);
> >
> > #endif
> > diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h
> > b/drivers/gpu/drm/i915/display/intel_display_types.h
> > index 73197f014510..6116c383b543 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> > @@ -1876,10 +1876,14 @@ struct intel_dp {
> > u8 fast_wake_lines;
> >
> > /* LNL and beyond */
> > + bool auxless_alpm_supported;
> > u8 check_entry_lines;
> > u8 silence_period_sym_clocks;
> > u8 lfps_half_cycle_num_of_syms;
> > } alpm_parameters;
> > +
> > + /* LOBF flags*/
> > + bool lobf_supported;
>
> I think having it here and naming like this is misleading. How about
> intel_crtc_state->has_lobf?
How about "bool lobf_entry_criteria" ?
>
> > };
> >
> > enum lspcon_vendor {
> > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> > b/drivers/gpu/drm/i915/display/intel_dp.c
> > index 163da48bc406..12ec796568d9 100644
> > --- a/drivers/gpu/drm/i915/display/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> > @@ -48,6 +48,7 @@
> > #include "i915_drv.h"
> > #include "i915_irq.h"
> > #include "i915_reg.h"
> > +#include "intel_alpm.h"
> > #include "intel_atomic.h"
> > #include "intel_audio.h"
> > #include "intel_backlight.h"
> > @@ -3001,6 +3002,7 @@ intel_dp_compute_config(struct intel_encoder
> > *encoder,
> > intel_vrr_compute_config(pipe_config, conn_state);
> > intel_dp_compute_as_sdp(intel_dp, pipe_config);
> > intel_psr_compute_config(intel_dp, pipe_config, conn_state);
> > + intel_alpm_compute_lobf_config(intel_dp, pipe_config,
> > conn_state);
> > intel_dp_drrs_compute_config(connector, pipe_config,
> > link_bpp_x16);
> > intel_dp_compute_vsc_sdp(intel_dp, pipe_config, conn_state);
> > intel_dp_compute_hdr_metadata_infoframe_sdp(intel_dp,
> > pipe_config, conn_state);
> > @@ -6616,6 +6618,9 @@ static bool intel_edp_init_connector(struct
> > intel_dp *intel_dp,
> >
> > intel_pps_init_late(intel_dp);
> >
> > + if (intel_dp_get_aux_less_alpm_status(intel_dp))
> > + intel_dp->alpm_parameters.auxless_alpm_supported =
> > true;
> > +
>
> intel_dp->alpm_parameters.auxless_alpm_supported =
> intel_dp_get_aux_less_alpm_status(intel_dp);
Ok.
Regards,
Animesh
>
> BR,
>
> Jouni Högander
>
> > return true;
> >
> > out_vdd_off:
