From a308ccb3a93bc665ed0f6bc864960795e2955532 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Fri, 4 Dec 2015 22:22:50 +0200 Subject: [PATCH] drm/i915: Leave FDI running after failed link training on LPT-H MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Currently we disable some parts of FDI setup after a failed link training. But despite that we continue with the modeset as if everything is fine. This results in tons of noise from the state checker, and it means we're not following the proper modeset sequence for the rest of crtc enabling, nor for crtc disabling. Ideally we should abort the modeset and follow the proper disable sequence to shut off everything we enabled so far, but that would require a big rework of the modeset code. So instead just leave FDI up and running in its untrained state, and log an error. This is what we do on older platforms too. v2: Fix a typo in the commit message Signed-off-by: Ville Syrjälä Reviewed-by: Paulo Zanoni Link: http://patchwork.freedesktop.org/patch/msgid/1449260570-14670-1-git-send-email-ville.syrjala@linux.intel.com --- drivers/gpu/drm/i915/intel_ddi.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c index 7f618cf5289c..5d20c64d8566 100644 --- a/drivers/gpu/drm/i915/intel_ddi.c +++ b/drivers/gpu/drm/i915/intel_ddi.c @@ -675,15 +675,16 @@ void hsw_fdi_link_train(struct drm_crtc *crtc) temp = I915_READ(DP_TP_STATUS(PORT_E)); if (temp & DP_TP_STATUS_AUTOTRAIN_DONE) { DRM_DEBUG_KMS("FDI link training done on step %d\n", i); + break; + } - /* Enable normal pixel sending for FDI */ - I915_WRITE(DP_TP_CTL(PORT_E), - DP_TP_CTL_FDI_AUTOTRAIN | - DP_TP_CTL_LINK_TRAIN_NORMAL | - DP_TP_CTL_ENHANCED_FRAME_ENABLE | - DP_TP_CTL_ENABLE); - - return; + /* + * Leave things enabled even if we failed to train FDI. + * Results in less fireworks from the state checker. + */ + if (i == ARRAY_SIZE(hsw_ddi_translations_fdi) * 2 - 1) { + DRM_ERROR("FDI link training failed!\n"); + break; } temp = I915_READ(DDI_BUF_CTL(PORT_E)); @@ -712,7 +713,12 @@ void hsw_fdi_link_train(struct drm_crtc *crtc) POSTING_READ(FDI_RX_MISC(PIPE_A)); } - DRM_ERROR("FDI link training failed!\n"); + /* Enable normal pixel sending for FDI */ + I915_WRITE(DP_TP_CTL(PORT_E), + DP_TP_CTL_FDI_AUTOTRAIN | + DP_TP_CTL_LINK_TRAIN_NORMAL | + DP_TP_CTL_ENHANCED_FRAME_ENABLE | + DP_TP_CTL_ENABLE); } void intel_ddi_init_dp_buf_reg(struct intel_encoder *encoder) -- 2.11.0