Ubuntu
linux-oem-5.10 package

  1. Focal (20.04)
  2. Bug #1913372
  3. Comment #0

Comment 0 for bug 1913372

Revision history for this message
koba (kobako) wrote :

[Impact]
WD19TB would report the number of lane(2-lane) and it works well on Type-C port of TGL platform.
Change the LTTPR mode to non-transparent mode, WD19TB would report the larger number of lane(4-lane). It's over the type-c port's bandwidth.

[Fix]
The patch is provided by Imre(https://patchwork.freedesktop.org/series/86267/).
Calculate the PBN divider value based on the rate and lane count link parameters
that the driver uses for all other computation.

[Test Case]
1. Connected the WD19TB with the TGL platform's Type-C port and
connected the external monitor on WD19TB with HDMI/Displayport.
2. Cold boot the TGL platform.
4. Check the monitor can be blinked and the video can output to the monitor.

[Where problems could occur]
It's more reasonable to calculate the PBN divider based on the source's rate and lane count,
not the mst's capability.