drm/i915/dp: Read ALPM caps after DPCD init

For eDP read the ALPM DPCD caps after DPCD initalization and just before
the PSR init.

v2: Move intel_alpm_init to intel_edp_init_dpcd (Jouni)
v3: Add Fixes with commit-id (Jouni)
v4: Separated the alpm dpcd read caps from alpm_init and moved to
intel_edp_init_dpcd.
v5: Read alpm_caps always for eDP irrespective of the eDP version (Jouni)
v6: replace drm_dp_dpcd_readb with drm_dp_dpcd_read_byte (Jouni)

Fixes: 15438b325987 ("drm/i915/alpm: Add compute config for lobf")
Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com>
Reviewed-by: Animesh Manna <animesh.manna@intel.com>
Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Link: https://patch.msgid.link/20260304072157.1123283-1-arun.r.murthy@intel.com
(cherry picked from commit 88442ba208dd5d3405de3f5000cf5b2c86876ae3)
Signed-off-by: Tvrtko Ursulin <tursulin@ursulin.net>

diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c b/drivers/gpu/drm/i915/display/intel_alpm.c
index 07ffee38974b07bde6a06c0f657f43d248102f45..f4f1b68f75435fbd14cf8ad62cfc7be2abf8cfef 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_alpm.c
+++ b/drivers/gpu/drm/i915/display/intel_alpm.c
@@ -43,12 +43,6 @@ bool intel_alpm_is_alpm_aux_less(struct intel_dp *intel_dp,
 
 void intel_alpm_init(struct intel_dp *intel_dp)
 {
-       u8 dpcd;
-
-       if (drm_dp_dpcd_readb(&intel_dp->aux, DP_RECEIVER_ALPM_CAP, &dpcd) < 0)
-               return;
-
-       intel_dp->alpm_dpcd = dpcd;
        mutex_init(&intel_dp->alpm.lock);
 }
 

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 559cf3bb23fdfd40de2bbf7040880bcbc492cc87..696edf40b2436128463cd36903f6ffe6918522f7 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -4577,6 +4577,7 @@ static bool
 intel_edp_init_dpcd(struct intel_dp *intel_dp, struct intel_connector *connector)
 {
        struct intel_display *display = to_intel_display(intel_dp);
+       int ret;
 
        /* this function is meant to be called only once */
        drm_WARN_ON(display->drm, intel_dp->dpcd[DP_DPCD_REV] != 0);
@@ -4616,6 +4617,12 @@ intel_edp_init_dpcd(struct intel_dp *intel_dp, struct intel_connector *connector
         */
        intel_dp_init_source_oui(intel_dp);
 
+       /* Read the ALPM DPCD caps */
+       ret = drm_dp_dpcd_read_byte(&intel_dp->aux, DP_RECEIVER_ALPM_CAP,
+                                   &intel_dp->alpm_dpcd);
+       if (ret < 0)
+               return false;
+
        /*
         * This has to be called after intel_dp->edp_dpcd is filled, PSR checks
         * for SET_POWER_CAPABLE bit in intel_dp->edp_dpcd[1]