Re: [PATCH] PCI: Extend Apple Thunderbolt power quirk to Alpine Ridge

[sashiko-bot@kernel.org]

> On Macs with an Alpine Ridge Thunderbolt 3 controller, suspending to RAM
> with anything plugged into a USB-C port leaves the PCIe link between the
> root port and the controller's upstream bridge permanently untrained on
> resume.  The link does not merely fall back to a lower speed: it never
> starts.  On a MacBookPro14,3 the root port reports
> 
>   LnkSta:  Speed 2.5GT/s, Width x0
>   LnkSta2: EqualizationComplete- EqualizationPhase1- Phase2- Phase3-
> 
> with no correctable, non-fatal or fatal errors logged, and the link
> training state machine stuck at its first state.  Both Thunderbolt
> controllers, both integrated xHCIs and all four USB-C ports are lost
> until reboot.  Measured 15 failures out of 15 with a device attached,
> against 5 successes out of 5 with the ports empty; it follows the device,
> not the port, and affects either controller.
> [ ... ]
>     and leaving it out is the conservative choice.
> 
> Tested on 6.18.49 on a MacBookPro14,3.
> 
> Signed-off-by: Francisco Beltrán Millalén <fbeltranmillalen@gmail.com>

Sashiko has reviewed this patch and found no issues. It looks great!

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Sashiko AI review · https://sashiko.dev/#/patchset/20260924132815.24430-1-fbeltranmillalen@gmail.com?part=1