drm/i915/lobf: Check for sink error and disable LOBF

Disable LOBF/ALPM for any erroneous condition from sink side.

v1: Initial version.
v2: Add centralized alpm error handling. [Jouni]
v3: Improve debug print. [Jouni]
v4: Disable alpm permanently for sink error. [Jouni]

Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
Link: https://lore.kernel.org/r/20250423092334.2294483-10-animesh.manna@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c b/drivers/gpu/drm/i915/display/intel_alpm.c
index 606cb3e5f30d1d99e2ea4ae13dc1ad8f6cadbab9..24b666e6d8f9b9a4d9276aa80bb8383eca22d3fd 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_alpm.c
+++ b/drivers/gpu/drm/i915/display/intel_alpm.c
@@ -284,6 +284,9 @@ void intel_alpm_lobf_compute_config(struct intel_dp *intel_dp,
                return;
        }
 
+       if (intel_dp->alpm_parameters.sink_alpm_error)
+               return;
+
        if (!intel_dp_is_edp(intel_dp))
                return;
 
@@ -546,5 +549,30 @@ void intel_alpm_disable(struct intel_dp *intel_dp)
                     PORT_ALPM_CTL(cpu_transcoder),
                     PORT_ALPM_CTL_ALPM_AUX_LESS_ENABLE, 0);
 
+       drm_dbg_kms(display->drm, "Disabling ALPM\n");
        mutex_unlock(&intel_dp->alpm_parameters.lock);
 }
+
+bool intel_alpm_get_error(struct intel_dp *intel_dp)
+{
+       struct intel_display *display = to_intel_display(intel_dp);
+       struct drm_dp_aux *aux = &intel_dp->aux;
+       u8 val;
+       int r;
+
+       r = drm_dp_dpcd_readb(aux, DP_RECEIVER_ALPM_STATUS, &val);
+       if (r != 1) {
+               drm_err(display->drm, "Error reading ALPM status\n");
+               return true;
+       }
+
+       if (val & DP_ALPM_LOCK_TIMEOUT_ERROR) {
+               drm_dbg_kms(display->drm, "ALPM lock timeout error\n");
+
+               /* Clearing error */
+               drm_dp_dpcd_writeb(aux, DP_RECEIVER_ALPM_STATUS, val);
+               return true;
+       }
+
+       return false;
+}

diff --git a/drivers/gpu/drm/i915/display/intel_alpm.h b/drivers/gpu/drm/i915/display/intel_alpm.h
index c043a071f84f3124a11f0f15a0d8d6990c0e9e17..d7126d65b60fb1625d1d569dbe88814c55ffb31b 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_alpm.h
+++ b/drivers/gpu/drm/i915/display/intel_alpm.h
@@ -31,4 +31,5 @@ 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);
 void intel_alpm_disable(struct intel_dp *intel_dp);
+bool intel_alpm_get_error(struct intel_dp *intel_dp);
 #endif

diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
index 878f378577ab64e554bb728a7b3aa8bf44e8e201..7415564d058a2e9db7eb3377349eada7fdb037ea 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_display_types.h
+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
@@ -1817,6 +1817,7 @@ struct intel_dp {
                u8 silence_period_sym_clocks;
                u8 lfps_half_cycle_num_of_syms;
                bool lobf_disable_debug;
+               bool sink_alpm_error;
        } alpm_parameters;
 
        u8 alpm_dpcd;

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index ece787bb3335750da7c14577209588ea48c91415..607aea1bf6fa28842bce5f67100b95e2baa18975 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -5392,6 +5392,11 @@ intel_dp_short_pulse(struct intel_dp *intel_dp)
 
        intel_psr_short_pulse(intel_dp);
 
+       if (intel_alpm_get_error(intel_dp)) {
+               intel_alpm_disable(intel_dp);
+               intel_dp->alpm_parameters.sink_alpm_error = true;
+       }
+
        if (intel_dp_test_short_pulse(intel_dp))
                reprobe_needed = true;
 

diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
index b3d324bd5eff194bfeb356abde276df53d1469bc..a6b925d2b7b44a14dad3a1b4e80228a65e6a0b24 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_psr.c
+++ b/drivers/gpu/drm/i915/display/intel_psr.c
@@ -3465,29 +3465,15 @@ static int psr_get_status_and_error_status(struct intel_dp *intel_dp,
 
 static void psr_alpm_check(struct intel_dp *intel_dp)
 {
-       struct intel_display *display = to_intel_display(intel_dp);
-       struct drm_dp_aux *aux = &intel_dp->aux;
        struct intel_psr *psr = &intel_dp->psr;
-       u8 val;
-       int r;
 
        if (!psr->sel_update_enabled)
                return;
 
-       r = drm_dp_dpcd_readb(aux, DP_RECEIVER_ALPM_STATUS, &val);
-       if (r != 1) {
-               drm_err(display->drm, "Error reading ALPM status\n");
-               return;
-       }
-
-       if (val & DP_ALPM_LOCK_TIMEOUT_ERROR) {
+       if (intel_alpm_get_error(intel_dp)) {
                intel_psr_disable_locked(intel_dp);
                psr->sink_not_reliable = true;
-               drm_dbg_kms(display->drm,
-                           "ALPM lock timeout error, disabling PSR\n");
-
-               /* Clearing error */
-               drm_dp_dpcd_writeb(aux, DP_RECEIVER_ALPM_STATUS, val);
+               intel_alpm_disable(intel_dp);
        }
 }