[PATCH 06/11] drm/i915/alpm: Add new interface to check if AUXLess ALPM is used

[Nautiyal, Ankit K]

On 5/2/2025 2:28 PM, Jouni Högander wrote:
> we need to know if AUXLess ALPM is used when preparing for link
> training. Add new interface for this and use it in existing code where
> possible.
>
> Signed-off-by: Jouni Högander <jouni.hogander at intel.com>
> ---
>   drivers/gpu/drm/i915/display/intel_alpm.c | 18 ++++++++++++++++--
>   drivers/gpu/drm/i915/display/intel_alpm.h |  2 ++
>   2 files changed, 18 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c b/drivers/gpu/drm/i915/display/intel_alpm.c
> index 5e5bc91ca7b76..4a8d4b34fa89e 100644
> --- a/drivers/gpu/drm/i915/display/intel_alpm.c
> +++ b/drivers/gpu/drm/i915/display/intel_alpm.c
> @@ -26,6 +26,21 @@ bool intel_alpm_aux_less_wake_supported(struct intel_dp *intel_dp)
>   	return intel_dp->alpm_dpcd & DP_ALPM_AUX_LESS_CAP;
>   }
>   
> +/**
> + * intel_alpm_is_alpm_aux_less - Check if AUXLess ALPM is used
> + * @intel_dp: Intel DP
> + * @crtc_state: CRTC status

crtc state


> + *
> + * Check if AUXLess ALPM is used by LOBF (Link Off Between Frames) or by PSR
> + * (Panel Self Refresh)

Similar to comment in previous patch lets use `Return:` in line with 
kernel doc.

Patch LGTM.

Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal at intel.com>

> + */
> +bool intel_alpm_is_alpm_aux_less(struct intel_dp *intel_dp,
> +				 const struct intel_crtc_state *crtc_state)
> +{
> +	return intel_psr_needs_alpm_aux_less(intel_dp, crtc_state) ||
> +		(crtc_state->has_lobf && intel_alpm_aux_less_wake_supported(intel_dp));
> +}
> +
>   void intel_alpm_init(struct intel_dp *intel_dp)
>   {
>   	u8 dpcd;
> @@ -341,8 +356,7 @@ static void lnl_alpm_configure(struct intel_dp *intel_dp,
>   	 * Panel Replay on eDP is always using ALPM aux less. I.e. no need to
>   	 * check panel support at this point.
>   	 */
> -	if ((crtc_state->has_panel_replay && intel_dp_is_edp(intel_dp)) ||
> -	    (crtc_state->has_lobf && intel_alpm_aux_less_wake_supported(intel_dp))) {
> +	if (intel_alpm_is_alpm_aux_less(intel_dp, crtc_state)) {
>   		alpm_ctl = ALPM_CTL_ALPM_ENABLE |
>   			ALPM_CTL_ALPM_AUX_LESS_ENABLE |
>   			ALPM_CTL_AUX_LESS_SLEEP_HOLD_TIME_50_SYMBOLS |
> diff --git a/drivers/gpu/drm/i915/display/intel_alpm.h b/drivers/gpu/drm/i915/display/intel_alpm.h
> index d7126d65b60fb..83bbe0b7ff100 100644
> --- a/drivers/gpu/drm/i915/display/intel_alpm.h
> +++ b/drivers/gpu/drm/i915/display/intel_alpm.h
> @@ -30,6 +30,8 @@ void intel_alpm_post_plane_update(struct intel_atomic_state *state,
>   void intel_alpm_lobf_debugfs_add(struct intel_connector *connector);
>   bool intel_alpm_aux_wake_supported(struct intel_dp *intel_dp);
>   bool intel_alpm_aux_less_wake_supported(struct intel_dp *intel_dp);
> +bool intel_alpm_is_alpm_aux_less(struct intel_dp *intel_dp,
> +				 const struct intel_crtc_state *crtc_state);
>   void intel_alpm_disable(struct intel_dp *intel_dp);
>   bool intel_alpm_get_error(struct intel_dp *intel_dp);
>   #endif