Hi, On Mon, Feb 28, 2022 at 10:36:59PM +0000, Limonciello, Mario wrote: > [AMD Official Use Only] > > > -----Original Message----- > > From: Lukas Wunner <lukas@xxxxxxxxx> > > Sent: Monday, February 28, 2022 16:33 > > To: Bjorn Helgaas <helgaas@xxxxxxxxxx> > > Cc: Limonciello, Mario <Mario.Limonciello@xxxxxxx>; Mika Westerberg > > <mika.westerberg@xxxxxxxxxxxxxxx>; Michael Jamet > > <michael.jamet@xxxxxxxxx>; open list:PCI SUBSYSTEM <linux- > > pci@xxxxxxxxxxxxxxx>; open list:THUNDERBOLT DRIVER <linux- > > usb@xxxxxxxxxxxxxxx>; Yehezkel Bernat <YehezkelShB@xxxxxxxxx>; open > > list:DRM DRIVERS <dri-devel@xxxxxxxxxxxxxxxxxxxxx>; open list:X86 > > PLATFORM DRIVERS <platform-driver-x86@xxxxxxxxxxxxxxx>; Andreas > > Noever <andreas.noever@xxxxxxxxx>; open list:RADEON and AMDGPU > > DRM DRIVERS <amd-gfx@xxxxxxxxxxxxxxxxxxxxx>; open list:DRM DRIVER FOR > > NVIDIA GEFORCE/QUADRO GPUS <nouveau@xxxxxxxxxxxxxxxxxxxxx>; Bjorn > > Helgaas <bhelgaas@xxxxxxxxxx>; Deucher, Alexander > > <Alexander.Deucher@xxxxxxx> > > Subject: Re: [PATCH v5 3/7] PCI: Drop the `is_thunderbolt` attribute from PCI > > core > > > > On Mon, Feb 28, 2022 at 04:13:44PM -0600, Bjorn Helgaas wrote: > > > On Mon, Feb 28, 2022 at 03:33:13PM +0000, Limonciello, Mario wrote: > > > > > On Fri, Feb 25, 2022 at 11:42:24AM -0600, Bjorn Helgaas wrote: > > > > > > That would just leave the "PCI_VSEC_ID_INTEL_TBT implies external- > > > > > facing" > > > > > > assumption above. Not having a Thunderbolt spec, I have no idea > > how > > > > > > you deal with that. > > > > > > > > > > You can download the spec here: > > [...] > > > > > Inside the archive there is also the DVSEC spec with name "USB4 DVSEC > > > > > Version 1.0.pdf". > > > > > > > > The spec has Host_Router_indication (bits 18-19) as meaning external > > facing. > > > > I'll respin the patch 3 for using that. > > > > > > Thanks, please include the spec citation when you do. And probably > > > the URL, because it's not at all obvious how the casual reader would > > > get from "is_thunderbolt" to a recent add-on to the USB4 spec. > > > > PCI_VSEC_ID_INTEL_TBT is not mentioned at all in the USB4 spec, > > hence there's no connection between "is_thunderbolt" and the USB4 spec. > > > > It's a proprietary VSEC used by Intel and the only way to recognize > > pre-USB4 Thunderbolt devices that I know of. Its ID is also > > different from the DVSEC IDs given in the above-mentioned spec. > > > > Thanks, > > The USB4 DVSEC spec makes comments about DVSEC_ID of 0x8086 and also > DVSEC VENDOR_ID of 0x8086. Is that not also present on the Intel TBT3 controllers? > > My interpretation of this (and Mika's comment) was that rather than > looking at the Intel VSEC we should look at the USB4 DVSEC to detect > the Intel TBT3 controllers. For pre-USB4 controllers (TBT 1-3) we need to use the existing method (or a quirk based on device ID) as they don't have the USB4 DVSEC.
