Re: [PATCH v2 6/9] PCI: Rename is_thunderbolt to is_tunneled

[Mario Limonciello]

On 11/5/2023 11:39, Lukas Wunner wrote:
> On Fri, Nov 03, 2023 at 02:07:55PM -0500, Mario Limonciello wrote:
> > The `is_thunderbolt` bit has been used to indicate that a PCIe device
> > contained the Intel VSEC which is used by various parts of the kernel
> > to change behavior. To later allow usage with USB4 controllers as well,
> > rename this to `is_tunneled`.
>
> This doesn't seem to make sense.  is_thunderbolt indicates that a device
> is part of a Thunderbolt controller.  See the code comment:
>
> > -	unsigned int	is_thunderbolt:1;	/* Thunderbolt controller */
>
> A Thunderbolt controller is not necessarily tunneled.  The PCIe switch,
> NHI and XHCI of the Thunderbolt host controller are not tunneled at all.
>
> Thanks,
>
> Lukas

I could really use some clarification which PCIe devices actually 
contain the Intel VSEC.

Is it in all 3 of those PCIe devices and not just the switch?

If so, I think I would rather introduce a separate bit.  So after this 
series we would have:

is_tunneled:1
is_thunderbolt:1
no_command_complete:1

* TBT1 devices would set no_command_complete
  - The consumer would be pcie_init()
* All devices with the Intel VSEC would set is_thunderbolt and the two 
consumers would be:
 - apple-gmux.c
 - pci_bridge_d3_possible()
* USB4 devices and PCIe switches with the VSEC would set is_tunneled.