diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 8aecb072466b..dcc7ae6d4141 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -1334,10 +1334,16 @@ intel_dp_start_link_train(struct intel_dp *intel_dp) u32 reg; uint32_t DP = intel_dp->DP; - /* Enable output, wait for it to become active */ - I915_WRITE(intel_dp->output_reg, intel_dp->DP); - POSTING_READ(intel_dp->output_reg); - intel_wait_for_vblank(dev, intel_crtc->pipe); + /* + * On CPT we have to enable the port in training pattern 1, which + * will happen below in intel_dp_set_link_train. Otherwise, enable + * the port and wait for it to become active. + */ + if (!HAS_PCH_CPT(dev)) { + I915_WRITE(intel_dp->output_reg, intel_dp->DP); + POSTING_READ(intel_dp->output_reg); + intel_wait_for_vblank(dev, intel_crtc->pipe); + } /* Write the link configuration data */ intel_dp_aux_native_write(intel_dp, DP_LINK_BW_SET,