Link training failure is handled by lowering the link rate first until it reaches the minimum and keeping the lane count maximum and then lowering the lane count until it reaches minimim. These fallback values are saved and hotplug uevent is sent to the userspace after setting the connector link status property to BAD. Userspace should triiger another modeset on a uevent and if link status property is BAD. This will retrain the link at fallback values. This is repeated until the link is successfully trained. This has been validated to pass DP compliance. Manasi Navare (5): drm: Add a new connector property for link status drm/i915: Set link status property for DP connector drm/i915: Update CRTC state if connector link status property changed drm/i915: Find fallback link rate/lane count drm/i915: Implement Link Rate fallback on Link training failure drivers/gpu/drm/drm_atomic_helper.c | 7 ++ drivers/gpu/drm/drm_connector.c | 17 ++++ drivers/gpu/drm/i915/intel_ddi.c | 21 +++- drivers/gpu/drm/i915/intel_dp.c | 138 +++++++++++++++++++++++++- drivers/gpu/drm/i915/intel_dp_link_training.c | 12 ++- drivers/gpu/drm/i915/intel_drv.h | 12 ++- include/drm/drm_connector.h | 7 +- include/drm/drm_crtc.h | 5 + include/uapi/drm/drm_mode.h | 4 + 9 files changed, 214 insertions(+), 9 deletions(-) -- 1.9.1 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
