Re: USB4/TBT3 support [related side note?]

Mohammad Noureldin <mohammad_at_thelightbird.com> wrote on
Date: Fri, 20 Dec 2024 16:04:20 UTC

> . . .

This is more a note about a context that may in some ways be somewhat
analogous, despite TBT3+ and USB4+ not being involved.

The example that I have access to is a Windows DevKit 2023. It has
3 USB-A ports and 2 USB-C ports. FreeBSD works with the USB-A ones
but not with the USB-C ones. (The FreeBSD loader work for all --via
the UEFI/ACPI, of course.)

What seems to be unique that might contribute is that the 2 USB-C
ports also support HBR3 Transmission Mode (4 lane x 8.1 Gbps/lane)
that has support for:

SST: 5120x2880 @ 60Hz,
SST: 4096x2160 @ 60Hz,
MST: (x2) 3840x2160 @ 60Hz (RB2),
MST: (x2) 2560x1600 @ 60Hz (CVT, RB)

(Not that I use the USB-C ports at all. I stick to the USB-A
USB ports.)

I'm not proposing that you make the Windows DevKit 2023 USB-C
ports work. I just do not not know how common such a combination
is for USB-C. It may be more of an aarch64 specific combination
rather than anything generalizing much to amd64.

The Windows DevKit 2023 also has a mDP HBR2 port that I do use.

===
Mark Millard
marklmi at yahoo.com