[PATCH] drm/i915/pps: debug log the remaining power cycle delay to wait

[Borah, Chaitanya Kumar]

> -----Original Message-----
> From: Intel-gfx <intel-gfx-bounces at lists.freedesktop.org> On Behalf Of Jani
> Nikula
> Sent: Wednesday, December 4, 2024 9:31 PM
> To: intel-gfx at lists.freedesktop.org; intel-xe at lists.freedesktop.org
> Cc: Nikula, Jani <jani.nikula at intel.com>; Paul Menzel
> <pmenzel at molgen.mpg.de>
> Subject: [PATCH] drm/i915/pps: debug log the remaining power cycle delay to
> wait
> 
> While pps_init_delays() debug logs the power cycle delay, also debug log the
> actual remaining time to wait in wait_panel_power_cycle().
> 
> Note that this still isn't the full picture; the power sequencer may still wait after
> this one.
> 
> Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/13007
> Signed-off-by: Jani Nikula <jani.nikula at intel.com>

LGTM
Reviewed-by: Chaitanya Kumar Borah <chaitanya.kumar.borah at intel.com>



> 
> ---
> 
> Cc: Paul Menzel <pmenzel at molgen.mpg.de>
> ---
>  drivers/gpu/drm/i915/display/intel_pps.c | 19 ++++++++++---------
>  1 file changed, 10 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_pps.c
> b/drivers/gpu/drm/i915/display/intel_pps.c
> index 7784b3b760db..bfda52850150 100644
> --- a/drivers/gpu/drm/i915/display/intel_pps.c
> +++ b/drivers/gpu/drm/i915/display/intel_pps.c
> @@ -668,23 +668,24 @@ static void wait_panel_power_cycle(struct intel_dp
> *intel_dp)
>  	struct intel_display *display = to_intel_display(intel_dp);
>  	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
>  	ktime_t panel_power_on_time;
> -	s64 panel_power_off_duration;
> -
> -	drm_dbg_kms(display->drm,
> -		    "[ENCODER:%d:%s] %s wait for panel power cycle\n",
> -		    dig_port->base.base.base.id, dig_port->base.base.name,
> -		    pps_name(intel_dp));
> +	s64 panel_power_off_duration, remaining;
> 
>  	/* take the difference of current time and panel power off time
>  	 * and then make panel wait for power_cycle if needed. */
>  	panel_power_on_time = ktime_get_boottime();
>  	panel_power_off_duration = ktime_ms_delta(panel_power_on_time,
> intel_dp->pps.panel_power_off_time);
> 
> +	remaining = max(0, intel_dp->pps.panel_power_cycle_delay -
> +panel_power_off_duration);
> +
> +	drm_dbg_kms(display->drm,
> +		    "[ENCODER:%d:%s] %s wait for panel power cycle (%lld ms
> remaining)\n",
> +		    dig_port->base.base.base.id, dig_port->base.base.name,
> +		    pps_name(intel_dp), remaining);
> +
>  	/* When we disable the VDD override bit last we have to do the
> manual
>  	 * wait. */
> -	if (panel_power_off_duration < (s64)intel_dp-
> >pps.panel_power_cycle_delay)
> -		wait_remaining_ms_from_jiffies(jiffies,
> -				       intel_dp->pps.panel_power_cycle_delay -
> panel_power_off_duration);
> +	if (remaining)
> +		wait_remaining_ms_from_jiffies(jiffies, remaining);
> 
>  	wait_panel_status(intel_dp, IDLE_CYCLE_MASK, IDLE_CYCLE_VALUE);
> }
> --
> 2.39.5