drm/i915/dp_mst - wait longer during the clock recovery for Display port

[koba]

[Impact]
For some TGL platform, connect with the external monitor on the docking station(SC),
after cold/warm boot, the external monitor can't output the video and need to hotplug the docking station.

[Fix]
On the link-training phase, Wait longer during the clock recovery.

[test]
With the patch, The TGL-machine connect with the external monitor on docking station(SC) and
can output the video to the external monitor on docking station after cold/warm boot.

[Regression Potential]
Medium, it may not the root cause.

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:

apport-collect 1902861

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-focal' to 'verification-done-focal'. If the problem still exists, change the tag 'verification-needed-focal' to 'verification-failed-focal'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[koba (kobako)]

For 5.8, we will backport the real solution from linux-next.

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux-oem-5.6 - 5.6.0-1035.37

---------------
linux-oem-5.6 (5.6.0-1035.37) focal; urgency=medium

  * focal/linux-oem-5.6: 5.6.0-1035.37 -proposed tracker (LP: #1903149)

  * Packaging resync (LP: #1786013)
    - update dkms package versions

  * drm/i915/dp_mst - wait longer during the clock recovery for Display port
    (LP: #1902861)
    - SAUCE: drm/i915/dp_mst: wait longer during the clock recovery

  * Remove NVMe suspend-to-idle workaround (LP: #1897227)
    - Revert "UBUTU: SAUCE: pci: prevent Intel NVMe SSDPEKKF from entering D3"
    - Revert "UBUNTU: SAUCE: pci: prevent sk hynix nvme from entering D3"

  * Tiger Lake PMC core driver fixes (LP: #1899883)
    - x86/devicetable: Move x86 specific macro out of generic code
    - x86/cpu: Add consistent CPU match macros
    - platform/x86: Convert to new CPU match macros
    - platform/x86: intel_pmc_core: Add Atom based Jasper Lake (JSL) platform
      support
    - platform/x86: intel_pmc_core: Add debugfs entry to access sub-state
      residencies
    - platform/x86: intel_pmc_core: Add debugfs entry for low power mode status
      registers
    - platform/x86: intel_pmc_core: Refactor the driver by removing redundant code
    - platform/x86: intel_pmc_core: Remove slp_s0 attributes from tgl_reg_map
    - platform/x86: intel_pmc_core: Add an additional parameter to
      pmc_core_lpm_display()
    - platform/x86: intel_pmc_core: Dump low power status registers on an S0ix.y
      failure
    - platform/x86: intel_pmc_core: Add debugfs support to access live status
      registers
    - platform/x86: intel_pmc_core: Relocate pmc_core_*_display() to outside of
      CONFIG_DEBUG_FS
    - platform/x86: intel_pmc_core: Remove duplicate 'if' to create debugfs entry
    - platform/x86: intel_pmc_core: Add slp_s0_offset attribute back to
      tgl_reg_map
    - platform/x86: intel_pmc_core: Make pmc_core_lpm_display() generic for
      platforms that support sub-states
    - platform/x86: intel_pmc_core: Make pmc_core_substate_res_show() generic
    - platform/x86: intel_pmc_core: Change Jasper Lake S0ix debug reg map back to
      ICL
    - platform/x86: intel_pmc_core: avoid unused-function warnings
    - platform/x86: intel_pmc_core: update TGL's LPM0 reg bit map name
    - platform/x86: intel_pmc_core: fix bound check in pmc_core_mphy_pg_show()
    - platform/x86: pmc_core: Use descriptive names for LPM registers
    - platform/x86: intel_pmc_core: Fix TigerLake power gating status map
    - platform/x86: intel_pmc_core: Fix the slp_s0 counter displayed value

  * [SRU][OEM-5.6]Fix no video out from some monitors on amdgpu (LP: #1901135)
    - drm/amd/display: Retry AUX write when fail occurs

  * drm/i915/dp_mst - only read the base capability in DPCD. (LP: #1902613)
    - Revert "UBUNTU: SAUCE: drm/dp_mst: Retrieve extended DPCD caps for topology
      manager"

  * TGL system automatically resumes from s2idle when connecting to a docking
    station with a monitor (LP: #1902577)
    - SAUCE: ACPI: avoid auto-wakeup with an _OSI string

  * Fix non-working NVMe after S3 (LP: #1895718)
    - SAUCE: PCI: Enable ACS quirk on all CML root ports

  * drm...