drm/i915/dg2: Skip output init on PHY calibration failure

If one of our PHYs fails to complete calibration, we should skip the
general initialization of the corresponding output.  Most likely this is
going to happen on outputs that don't actually exist on the board; in
theory we should have already decided to skip this output based on the
VBT, but we can't always rely on the VBT being accurate.

Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220223165421.3949883-1-matthew.d.roper@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
index e4260806c2a40b336abe98b66a0ba2011a3bc4bd..1cd394b0585e271786e638f99da389724da93f6b 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_ddi.c
+++ b/drivers/gpu/drm/i915/display/intel_ddi.c
@@ -4308,6 +4308,14 @@ void intel_ddi_init(struct drm_i915_private *dev_priv, enum port port)
                return;
        }
 
+       if (intel_phy_is_snps(dev_priv, phy) &&
+           dev_priv->snps_phy_failed_calibration & BIT(phy)) {
+               drm_dbg_kms(&dev_priv->drm,
+                           "SNPS PHY %c failed to calibrate; output will not be used.\n",
+                           phy_name(phy));
+               return;
+       }
+
        dig_port = kzalloc(sizeof(*dig_port), GFP_KERNEL);
        if (!dig_port)
                return;

diff --git a/drivers/gpu/drm/i915/display/intel_snps_phy.c b/drivers/gpu/drm/i915/display/intel_snps_phy.c
index 7e6245b97fedab38898fa795a35d44411decfb83..0dd4775e8195eed62ed3e2eba732991811f5be3d 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_snps_phy.c
+++ b/drivers/gpu/drm/i915/display/intel_snps_phy.c
@@ -32,10 +32,14 @@ void intel_snps_phy_wait_for_calibration(struct drm_i915_private *i915)
                if (!intel_phy_is_snps(i915, phy))
                        continue;
 
+               /*
+                * If calibration does not complete successfully, we'll remember
+                * which phy was affected and skip setup of the corresponding
+                * output later.
+                */
                if (intel_de_wait_for_clear(i915, DG2_PHY_MISC(phy),
                                            DG2_PHY_DP_TX_ACK_MASK, 25))
-                       drm_err(&i915->drm, "SNPS PHY %c failed to calibrate after 25ms.\n",
-                               phy_name(phy));
+                       i915->snps_phy_failed_calibration |= BIT(phy);
        }
 }
 

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index e71dcd2701ca483cfa9611ae0e293691d6b1cf1c..5cfe69b308416ba7c3fa42699a8946993067085b 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -837,8 +837,16 @@ struct drm_i915_private {
 
        bool irq_enabled;
 
-       /* perform PHY state sanity checks? */
-       bool chv_phy_assert[2];
+       union {
+               /* perform PHY state sanity checks? */
+               bool chv_phy_assert[2];
+
+               /*
+                * DG2: Mask of PHYs that were not calibrated by the firmware
+                * and should not be used.
+                */
+               u8 snps_phy_failed_calibration;
+       };
 
        bool ipc_enabled;