[PATCH 4/4] drm/i915/psr: Allow changing Panel Replay mode without full modeset

[Kahola, Mika]

> -----Original Message-----
> From: Intel-xe <intel-xe-bounces at lists.freedesktop.org> On Behalf Of Jouni
> Högander
> Sent: Thursday, 9 January 2025 12.36
> To: intel-gfx at lists.freedesktop.org; intel-xe at lists.freedesktop.org
> Cc: Hogander, Jouni <jouni.hogander at intel.com>
> Subject: [PATCH 4/4] drm/i915/psr: Allow changing Panel Replay mode without
> full modeset
> 
> Currently we are forcing full modeset if Panel Replay mode is changed. This is not
> necessary as long as we are not changing sink PANEL REPLAY ENABLE bit in
> PANEL REPLAY ENABLE AND CONFIGURATION 1 register. This can be achieved by
> entering Panel Replay inactive mode (Live Frame mode) when Panel Replay is
> disabled and keep PANEL REPLAY ENABLE bit in PANEL REPLAY ENABLE AND
> CONFIGURATION 1 enabled always if panel is just supporting Panel Replay.
> 

Reviewed-by: Mika Kahola <mika.kahola at intel.com>

> Signed-off-by: Jouni Högander <jouni.hogander at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_display.c | 14 -----------
>  drivers/gpu/drm/i915/display/intel_psr.c     | 25 +++++++++++++-------
>  2 files changed, 17 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c
> b/drivers/gpu/drm/i915/display/intel_display.c
> index 21319f753a34..35499eb296b3 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -5638,20 +5638,6 @@ intel_pipe_config_compare(const struct
> intel_crtc_state *current_config,
>  		PIPE_CONF_CHECK_CSC(output_csc);
>  	}
> 
> -	/*
> -	 * Panel replay has to be enabled before link training. PSR doesn't have
> -	 * this requirement -> check these only if using panel replay
> -	 */
> -	if (current_config->active_planes &&
> -	    (current_config->has_panel_replay ||
> -	     pipe_config->has_panel_replay)) {
> -		PIPE_CONF_CHECK_BOOL(has_psr);
> -		PIPE_CONF_CHECK_BOOL(has_sel_update);
> -		PIPE_CONF_CHECK_BOOL(enable_psr2_sel_fetch);
> -		PIPE_CONF_CHECK_BOOL(enable_psr2_su_region_et);
> -		PIPE_CONF_CHECK_BOOL(has_panel_replay);
> -	}
> -
>  	PIPE_CONF_CHECK_BOOL(double_wide);
> 
>  	if (dev_priv->display.dpll.mgr)
> diff --git a/drivers/gpu/drm/i915/display/intel_psr.c
> b/drivers/gpu/drm/i915/display/intel_psr.c
> index f969abc56256..3494620d1c44 100644
> --- a/drivers/gpu/drm/i915/display/intel_psr.c
> +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> @@ -1998,18 +1998,25 @@ static void intel_psr_enable_locked(struct intel_dp
> *intel_dp,
>  	if (!psr_interrupt_error_check(intel_dp))
>  		return;
> 
> -	if (intel_dp->psr.panel_replay_enabled) {
> +	if (intel_dp->psr.panel_replay_enabled)
>  		drm_dbg_kms(display->drm, "Enabling Panel Replay\n");
> -	} else {
> +	else
>  		drm_dbg_kms(display->drm, "Enabling PSR%s\n",
>  			    intel_dp->psr.sel_update_enabled ? "2" : "1");
> 
> -		/*
> -		 * Panel replay has to be enabled before link training: doing it
> -		 * only for PSR here.
> -		 */
> -		intel_psr_enable_sink(intel_dp, crtc_state);
> -	}
> +	/*
> +	 * Enabling here only for PSR. Panel Replay enable bit is already
> +	 * written at this point. See
> +	 * intel_psr_panel_replay_enable_sink. Modifiers/options:
> +	 *  - Selective Update
> +	 *  - Region Early Transport
> +	 *  - Selective Update Region Scanline Capture
> +	 *  - VSC_SDP_CRC
> +	 *  - HPD on different Errors
> +	 *  - CRC verification
> +	 * are written for PSR and Panel Replay here.
> +	 */
> +	intel_psr_enable_sink(intel_dp, crtc_state);
> 
>  	if (intel_dp_is_edp(intel_dp))
>  		intel_snps_phy_update_psr_power_state(&dig_port->base,
> true); @@ -2815,6 +2822,8 @@ void intel_psr_pre_plane_update(struct
> intel_atomic_state *state,
>  		needs_to_disable |= new_crtc_state->has_sel_update != psr-
> >sel_update_enabled;
>  		needs_to_disable |= new_crtc_state-
> >enable_psr2_su_region_et !=
>  			psr->su_region_et_enabled;
> +		needs_to_disable |= new_crtc_state->has_panel_replay !=
> +			psr->panel_replay_enabled;
>  		needs_to_disable |= DISPLAY_VER(i915) < 11 &&
>  			new_crtc_state->wm_level_disabled;
> 
> --
> 2.34.1