On Mon, 2024-01-29 at 02:08 +0000, Murthy, Arun R wrote:
>
>
> > -----Original Message-----
> > From: Intel-gfx <intel-gfx-bounces@xxxxxxxxxxxxxxxxxxxxx> On Behalf
> > Of Jouni
> > Högander
> > Sent: Friday, January 5, 2024 7:45 PM
> > To: intel-gfx@xxxxxxxxxxxxxxxxxxxxx
> > Subject: [PATCH v2 3/4] drm/i915/alpm: Calculate ALPM Entry check
> >
> > ALPM Entry Check represents the number of lines needed to put the
> > main link
> > to sleep and keep it in the sleep state before it can be taken out
> > of the SLEEP
> > state (eDP requires the main link to be in the SLEEP state for a
> > minimum of
> > 5us).
> >
> > Bspec: 71477
> >
> > Signed-off-by: Jouni Högander <jouni.hogander@xxxxxxxxx>
> > ---
> > .../drm/i915/display/intel_display_types.h | 3 ++
> > drivers/gpu/drm/i915/display/intel_psr.c | 28
> > +++++++++++++++++++
> > 2 files changed, 31 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h
> > b/drivers/gpu/drm/i915/display/intel_display_types.h
> > index 889a8b34b7ac..7eddef859ff4 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> > @@ -1680,6 +1680,9 @@ struct intel_pps { struct alpm_parameters {
> > u8 io_wake_lines;
> > u8 fast_wake_lines;
> > +
> > + /* LNL and beyond */
> > + u8 check_entry_lines;
> > };
> >
> > struct intel_psr {
> > diff --git a/drivers/gpu/drm/i915/display/intel_psr.c
> > b/drivers/gpu/drm/i915/display/intel_psr.c
> > index 1709ebb31215..7fbd18f21c3b 100644
> > --- a/drivers/gpu/drm/i915/display/intel_psr.c
> > +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> > @@ -1099,6 +1099,28 @@ static bool
> > _compute_psr2_sdp_prior_scanline_indication(struct intel_dp
> > *intel_d
> > return true;
> > }
> >
> > +static bool _lnl_compute_alpm_params(struct intel_dp *intel_dp,
> > + struct intel_crtc_state
> > *crtc_state) {
> > + struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> > + struct alpm_parameters *alpm_params = &intel_dp-
> > >psr.alpm_params;
> > + int check_entry_lines;
> > +
> > + /* ALPM Entry Check = 2 + CEILING( 5us /tline ) */
> > + check_entry_lines = 2 +
> > + intel_usecs_to_scanlines(&crtc_state-
> > >hw.adjusted_mode, 5);
> > +
> > + if (check_entry_lines > 15)
> > + return false;
> > +
> > + if (i915->display.params.psr_safest_params)
> > + check_entry_lines = 15;
> > +
> > + alpm_params->check_entry_lines = check_entry_lines;
> > +
> > + return true;
> > +}
> > +
> > static bool _compute_alpm_params(struct intel_dp *intel_dp,
> > struct intel_crtc_state
> > *crtc_state) { @@ -
> > 1114,6 +1136,8 @@ static bool _compute_alpm_params(struct intel_dp
> > *intel_dp,
> > * it is not enough -> use 45 us.
> > */
> > fast_wake_time = 45;
> > +
> > + /* TODO: Check how we can use ALPM_CTL fast wake
> > extended
> > field */
> > max_wake_lines = 12;
> > } else {
> > io_wake_time = 50;
> > @@ -1130,6 +1154,10 @@ static bool _compute_alpm_params(struct
> > intel_dp
> > *intel_dp,
> > fast_wake_lines > max_wake_lines)
> > return false;
> >
> > + if (DISPLAY_VER(i915) >= 20 &&
> > !_lnl_compute_alpm_params(intel_dp,
> > +
> > crtc_state))
> The function name _lnl_*** indicates it should be display ver 20. So
> can this display ver check be moved to _lnl_*** ?
Yes, I can do that.
BR,
Jouni Högander
>
> Thanks and Regards,
> Arun R Murthy
> -------------------
> > + return false;
> > +
> > if (i915->display.params.psr_safest_params)
> > io_wake_lines = fast_wake_lines = max_wake_lines;
> >
> > --
> > 2.34.1
>
