We are seeing "dmesg-warn/abort - *ERROR* PHY * failed after 3 retries" since we started configuring LFPS sending. According to Bspec Configuring LFPS sending is needed only when using AUXLess ALPM. This patch avoids these failures by configuring LFPS sending only when using AUXLess ALPM.
Addition to PHY failure fix this patch set contains some additions that were seen missing during review: 1. Ensure phy is accessible on lfps configuration 2. Set C10_VDR_CTRL_MSGBUS_ACCESS before phy reg read Also one optimization is added to avoid unnecessarily calling intel_cx0_get_owned_lane_mask. v3: - add Bpsec references - set C10_VDR_CTRL_MSGBUS_ACCESS once for all owned lanes v2: - split as a patch set - add ensuring phy is accessible on lfps configuration - set C10_VDR_CTRL_MSGBUS_ACCESS before phy reg read Jouni Högander (4): drm/i915/display: Write PHY_CMN1_CONTROL only when using AUXLess ALPM drm/i915/display: Avoid unnecessarily calling intel_cx0_get_owned_lane_mask drm/i915/display: Ensure phy is accessible on lfps configuration drm/i915/display: Set C10_VDR_CTRL_MSGBUS_ACCESS before phy reg read drivers/gpu/drm/i915/display/intel_cx0_phy.c | 21 ++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) -- 2.43.0