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Date:   Thu, 2 Nov 2023 16:33:45 +0100
From:   Lukas Wunner <lukas@wunner.de>
To:     Mario Limonciello <mario.limonciello@amd.com>
Cc:     Bjorn Helgaas <helgaas@kernel.org>, bhelgaas@google.com,
        mika.westerberg@linux.intel.com, andreas.noever@gmail.com,
        michael.jamet@intel.com, YehezkelShB@gmail.com,
        linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-usb@vger.kernel.org, Alexander.Deucher@amd.com
Subject: Re: [PATCH 2/2] PCI: Ignore PCIe ports used for tunneling in
 pcie_bandwidth_available()
Message-ID: <20231102153345.GA30347@wunner.de>
References: <20231101225259.GA101390@bhelgaas>
 <928df647-5b20-406b-8da5-3199f5cfbb48@amd.com>
 <20231102152154.GA22270@wunner.de>
 <bb4d8fad-dced-4fed-9582-2db50643e868@amd.com>
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On Thu, Nov 02, 2023 at 10:26:31AM -0500, Mario Limonciello wrote:
> On 11/2/2023 10:21, Lukas Wunner wrote:
> > On Wed, Nov 01, 2023 at 08:14:31PM -0500, Mario Limonciello wrote:
> > > Considering this I think it's a good idea to move that creation of the
> > > device link into drivers/pci/pci-acpi.c and store a bit in struct
> > > pci_device to indicate it's a tunneled port.
> > > 
> > > Then 'thunderbolt' can look for this directly instead of walking all
> > > the FW nodes.
> > > 
> > > pcie_bandwidth_available() can just look at the tunneled port bit
> > > instead of the existence of the device link.
> > 
> > pci_is_thunderbolt_attached() should already be doing exactly what
> > you want to achieve with the new bit.  It tells you whether a PCI
> > device is behind a Thunderbolt tunnel.  So I don't think a new bit
> > is actually needed.
> 
> It's only for a device connected to an Intel TBT3 controller though; it
> won't apply to USB4.

Time to resurrect this patch here...? :)

https://lore.kernel.org/all/20220204182820.130339-3-mario.limonciello@amd.com/