Re: [PATCH 13/19] thunderbolt: Add QUIRK_NO_DMA_PORT

[Sven Peter]

On 9/1/26 11:04, Mika Westerberg wrote:
> Hi,
>
> On Sun, Aug 30, 2026 at 10:19:31PM +0200, Sven Peter wrote:
> > Apple Silicon machines load and update the host router firmware with a
> > separate, proprietary mechanism and have no DMA port. Add a quirk to
> > skip its initialization.
> DMA port is Intel Thunderbolt 1-3 thing and not expected to found on USB4
> routers. The current code should not even be trying to find it, if it does
> then that's a bug that should be fixed.
>
> USB4 router firmware upgrades use the standard operations and if those are
> not supported then we just don't expose the corresponding NVMem nodes.

Yeah, you're right, I can just drop this and everything still works.
I think this may have been broken back in 2023 when I brought this all 
up for the first time (and still had trouble with the Type-C PHY and PD 
controller which is why I didn't try to upstream any of this back then)


Sven