NACK [SRU][OEM-5.14/J][PATCH 0/4] Fix DP tunneling issues on AMD Rembrandt

Mario Limonciello mario.limonciello at amd.com
Wed Aug 3 14:44:41 UTC 2022


On 8/1/22 03:43, Stefan Bader wrote:
> On 29.07.22 20:56, Mario Limonciello wrote:
>> BugLink: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1983143
>>
>> When a Thunderbolt monitor or Thunderbolt dock are connected to a USB4
>> port on AMD Yellow Carp (Rembrandt) a software connection manager works
>> with the hardware to initialize tunnels.
>>
>> One of those tunnels is for DP (display port). It was observed that
>> on both the OEM-5.14 as well as Jammy-5.15 kernel that DP tunneling
>> specifically when connecting to a Thunderbolt monitor fails.
>> This circumstance does not happen on OEM-5.17 or mainline kernels.
>>
>> This is due to a backport error on the USB4 patch series that went
>> into OEM-5.14 and moved forward to Jammy-5.15.  Patch 1/4 in this
>> series corrects that error as minimally as possible as a SAUCE patch.
>>
>> It was also observed that DP tunneling is not working for Thunderbolt
>> monitor connected at boot, but this is a different root cause.
>> The "Pre-OS" connection manager creates DP tunnels that are expected
>> to be re-used by the OS connection manager. The remaining patches in
>> this series enable this flow.
>>
>> For this whole flow to work an updated AMDGPU DMCUB firmware is also
>> needed.  This is already in process as part of:
>> https://bugs.launchpad.net/ubuntu/+source/linux-firmware/+bug/1981922
>>
>> Mario Limonciello (1):
>>    UBUNTU: SAUCE: drm/amd: Fix DP Tunneling with Thunderbolt monitors
> 
> Hi Mario,
> 
> while your patch contains good reasoning for why it is a non-upstream 
> patch, the other SAUCE patch is not that clear. From the s-o-b reference 
> it sounds like it might go upstream which makes one wonder why not 
> taking it from there.
> 
>>
>> Meenakshikumar Somasundaram (1):
>>    drm/amd/display: Fix for dmub outbox notification enable
>>
>> Sanjay R Mehta (1):
>>    UBUNTU: SAUCE: thunderbolt: Add DP out resource when DP tunnel is
>>      discovered.
>>
>> Stylon Wang (1):
>>    drm/amd/display: Fix new dmub notification enabling in DM
> 
> That one ^ I would rather declare a backport and annotate with short 
> hints about what was worked around. Like "use <name> instead of <other 
> name>". Mentioning which changes are missing is nice in addition but for 
> glancing over submissions it is much simpler to get told what to watch 
> out for.
> 
> To be clear I am not asking to re-submit. If we can clarify things we 
> can make the adjustments when we apply things.
> 
> -Stefan
> 
>>
>>   .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 24 +++++--
>>   drivers/gpu/drm/amd/display/dc/core/dc.c      | 66 +++++++++++++++++--
>>   drivers/gpu/drm/amd/display/dc/dc.h           |  3 +
>>   .../gpu/drm/amd/display/dc/dce/dmub_outbox.c  | 25 +++----
>>   .../gpu/drm/amd/display/dc/dce/dmub_outbox.h  |  4 +-
>>   .../amd/display/dc/dcn10/dcn10_hw_sequencer.c |  4 --
>>   .../drm/amd/display/dc/dcn20/dcn20_hwseq.c    |  4 ++
>>   .../drm/amd/display/dc/dcn31/dcn31_hwseq.c    |  2 +-
>>   drivers/thunderbolt/tb.c                      | 15 +++++
>>   drivers/thunderbolt/tb.h                      |  1 +
>>   drivers/thunderbolt/tunnel.c                  |  2 +
>>   11 files changed, 121 insertions(+), 29 deletions(-)
>>
> 

This series was resubmitted to fix a mistake in 1/4 and to adjust 
context for making 3/4 apply cleanly as backports.  Please NACK this 
series and lets follow discussion on v2.



More information about the kernel-team mailing list