[PATCH v4 6/8] drm/i915/lobf: Check for sink error and disable LOBF

[Animesh Manna]

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

v1: Initial version.
v2: Add centralized alpm error handling. [Jouni]

Signed-off-by: Animesh Manna <animesh.ma...@intel.com>
---
 drivers/gpu/drm/i915/display/intel_alpm.c | 25 +++++++++++++++++++++++
 drivers/gpu/drm/i915/display/intel_alpm.h |  1 +
 drivers/gpu/drm/i915/display/intel_dp.c   |  3 +++
 drivers/gpu/drm/i915/display/intel_psr.c  | 15 ++------------
 4 files changed, 31 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c 
b/drivers/gpu/drm/i915/display/intel_alpm.c
index 5c70677ac3c0..92ec03956755 100644
--- a/drivers/gpu/drm/i915/display/intel_alpm.c
+++ b/drivers/gpu/drm/i915/display/intel_alpm.c
@@ -532,3 +532,28 @@ void intel_alpm_disable(struct intel_dp *intel_dp)
                     PORT_ALPM_CTL(cpu_transcoder),
                     PORT_ALPM_CTL_ALPM_AUX_LESS_ENABLE, 0);
 }
+
+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, disabling ALPM\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 c6efd25c2062..22469fd4cba5 100644
--- a/drivers/gpu/drm/i915/display/intel_alpm.h
+++ b/drivers/gpu/drm/i915/display/intel_alpm.h
@@ -30,4 +30,5 @@ 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_dp.c 
b/drivers/gpu/drm/i915/display/intel_dp.c
index 03ca2e02ab02..24ad7680cdf2 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -5360,6 +5360,9 @@ 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);
+
        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 1d202f2eb356..fde9463d5ec9 100644
--- a/drivers/gpu/drm/i915/display/intel_psr.c
+++ b/drivers/gpu/drm/i915/display/intel_psr.c
@@ -3406,28 +3406,17 @@ 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;
+               intel_alpm_disable(intel_dp);
                drm_dbg_kms(display->drm,
                            "ALPM lock timeout error, disabling PSR\n");
-
-               /* Clearing error */
-               drm_dp_dpcd_writeb(aux, DP_RECEIVER_ALPM_STATUS, val);
        }
 }
 
-- 
2.29.0