Re: [PATCH 1/2] drm/i915/psr: Simplify the conditions for SCL computation

[Jani Nikula <jani.nikula@linux.intel.com>]

On Fri, 15 May 2026, Ankit Nautiyal <ankit.k.nautiyal@intel.com> wrote:
> The SCL condition checks can be combined into one expression.
> needs_sel_update is common for both display version branches, so check it
> once and keep the version specific checks together.
>
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_psr.c | 13 +++++--------
>  1 file changed, 5 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
> index 8f70b7dcd881..5bf1d782188c 100644
> --- a/drivers/gpu/drm/i915/display/intel_psr.c
> +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> @@ -1477,15 +1477,12 @@ int _intel_psr_min_set_context_latency(const struct intel_crtc_state *crtc_state
>  	 * SRD_STATUS is used by PSR1 and Panel Replay DP on LunarLake.
>  	 */
>  
> -	if (DISPLAY_VER(display) >= 30 && (needs_panel_replay ||
> -					   needs_sel_update))
> +	if (needs_sel_update ||
> +	    (DISPLAY_VER(display) >= 30 && needs_panel_replay) ||
> +	    (DISPLAY_VER(display) < 30 && intel_crtc_has_type(crtc_state, INTEL_OUTPUT_EDP)))
>  		return 0;
> -	else if (DISPLAY_VER(display) < 30 && (needs_sel_update ||
> -					       intel_crtc_has_type(crtc_state,
> -								   INTEL_OUTPUT_EDP)))
> -		return 0;
> -	else
> -		return 1;

The function has a bunch of simple "if foo return bar" statements.

Please don't combine more stuff together, but rather split them up.

	if (needs_sel_update)
		return 0;

	if (DISPLAY_VER(display) < 30 && intel_crtc_has_type(crtc_state, INTEL_OUTPUT_EDP))
		return 0;

	if (DISPLAY_VER(display) >= 30 && needs_panel_reply)
		return 0;

Please consider which one is easier and faster to read and understand.

BR,
Jani.


> +
> +	return 1;
>  }
>  
>  static bool _wake_lines_fit_into_vblank(const struct intel_crtc_state *crtc_state,

-- 
Jani Nikula, Intel