[PATCH v2 19/22] thunderbolt: Add Apple Silicon support

Sven Peter sven at kernel.org
Wed Sep 9 08:25:32 PDT 2026


On 09.09.26 17:20, Sven Peter wrote:
> Hi,
> 
> On 09.09.26 08:06, Mika Westerberg wrote:
> 
> [...]
> 
>>
>> If it is possible, I suggest to use the same way we do in ACPI side here:
>>
>> https://learn.microsoft.com/en-us/windows-hardware/drivers/pci/dsd- 
>> for-pcie-root-ports#map-native-protocols-pcie-displayport-tunneled- 
>> through-usb4-to-usb4-host-routers
>>
>> It was specifically designed so that it should support DT as well (that's
>> why it uses the device properties _DSD).
> 
> Oh, nice, I didn't know those existed. Konrad already has a PR open to 
> add these to dt-schema [1] and a PR that already makes use of these for 
> dwc3 [2].
> I can just write generic code similar to the ACPI one then to add the 
> device links and split it off from this series, though I think that dt- 
> schema PR must be merged before we're allowed to use that representation.
> I'll adjust the dt-bindings here for v3 to just drop the representation 
> as OF ports/endpoints as well.
> For the PCIe/DP tunnel notifications I should be able to use the same 
> representation, possibly with an additional usb4-adapter-index property 
> or similar to differentiate between the two DP IN adapters, once I get 
> to that then.

Though now that I read it again: do you know what PortInstance# in

Package () { "usb4-port-number", PortInstance#}, // PortInstance# is 
unused and can be 0
       }

refers to? Is that meant to e.g. by 0 for the first DP IN adapter and 1 
for the second? Or is that meant to be used when the NHI handles 
multiple Type-C ports? The description isn't clear to me...



Sven




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