Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) client-ip=23.128.96.37;
Message-ID: <bb4d8fad-dced-4fed-9582-2db50643e868@amd.com>
Date:   Thu, 2 Nov 2023 10:26:31 -0500
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH 2/2] PCI: Ignore PCIe ports used for tunneling in
 pcie_bandwidth_available()
Content-Language: en-US
To:     Lukas Wunner <lukas@wunner.de>
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
References: <20231101225259.GA101390@bhelgaas>
 <928df647-5b20-406b-8da5-3199f5cfbb48@amd.com>
 <20231102152154.GA22270@wunner.de>
From:   Mario Limonciello <mario.limonciello@amd.com>
In-Reply-To: <20231102152154.GA22270@wunner.de>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?TzNkQVZ5M2oyVnI1dDI2TTRhN0hJeWRiWVlleDJBM2ZJRXByalNXemtuZDRv?=
 =?utf-8?B?R1A3VEtpcndqWVErcEN6TlJ2bXFCTjRwVWdZZVZKcUQrYlVYa09haitYbEVR?=
 =?utf-8?B?dVVOWnY4N3Rhb3lCalNxR3Q5bXJDU3ZEUnNiYjY2bVl5K0haOWxsTy9uZWNx?=
 =?utf-8?B?cXpCMkNJY0RnSGtDNUovR0FsSUJCVDN6UlNRYVl6bGt6SzUwY1V2OUsveXgy?=
 =?utf-8?B?TU9GT2ttV0RNS1U2cVVKWEdjR2wxczVwdVBuU2hJaXlDZ1lhZmRZQWh3VEcv?=
 =?utf-8?B?WllVeTAzYkRpYisyd1docGtoY0lVKzBVd0hobk11QVRtaFN2NEQ1Z1JNSHZZ?=
 =?utf-8?B?cVR6WG5YUGJCRjhKeVdqUXZaMnVyeUUzaGRvdGF0WkRFcFNiQnZscVNuUDBM?=
 =?utf-8?B?OTlvOXU3cWNnUUxRejN4dm9EL21pU1JjelV4Y0hpRTBwZ09JU3lxWjdoYmUx?=
 =?utf-8?B?bFRHaitxK1NOaWNneUQ0c1J4S2dXZWZac281VkVSeTFSK0pxN2RTSUM5eDEv?=
 =?utf-8?B?VmdOWmFDY0N5dk1tVUloODEyZEtiaGxGSXExZXRRcjBITzFJNU5nL0xWTU5o?=
 =?utf-8?B?K0FObTYrVDNIeFpSVUVjRVVVWDNMdlU4Qk1DOFRuR0syRXgzSlh6dW5qM1Fr?=
 =?utf-8?B?djBSMFZkM1Q4S0F5eFB5dE5LWGYxUlN0ZW9DZWp5ZjhHYUtYYjRtdGMrdTZH?=
 =?utf-8?B?TGx3TmVPMVk0dmFIYmk4ZGJrK2FQcWVxTFo5SVFaUXdhbW1nRHppR0VnZms3?=
 =?utf-8?B?bXhpQzFWZUZrYjFZMVF6UzIyYTdicE1HSERvVVljRzI3WGVjYXVGS1dKT0g5?=
 =?utf-8?B?TnlnVS8veWFVVnRsTGw2QVNEdG1qZTdrSURZeDVVdE1jV3dzV0l1Y21ZUDBS?=
 =?utf-8?B?YXJkNWZlQ2pjSm0yRlIyOS9CSXJ1ZkFHUnhqekdyR1o4ckpBdGdRRWtadHBL?=
 =?utf-8?B?eVd4cm9wVjVUdGt6T0FPQThlM2NIbW51cjFqbmdDTmUvdGZkWUZ5YUxuTlVE?=
 =?utf-8?B?L3B0UFN5U3JUT1MxbEZ3Wlc2ellIR0ZnK3BZVnBUOUF0RkNLblFobTcyYjhw?=
 =?utf-8?B?NjVMdkhCbEQzUyszMWNwcVkwS3FxWmFDRSs1UHcxV3hzUGNQMEhEWmRNWDNT?=
 =?utf-8?B?NGFxV2pKbXFqY245aUJibWJxbU5IZnZvMldxWnY3bkN2MVUrQUJMTCtwVk9x?=
 =?utf-8?B?QUtuSUZkVGcyUmtnbU9VOTdKcFlmNDJJMllnVGZzNU9lcURuZllnNzcvcWt1?=
 =?utf-8?B?bUFKOHhXaGhhOVhGQmVKQmZJTHl1VGhBVTVhcDI2V3B5R3Y3aGsySlMvTUdk?=
 =?utf-8?B?UUR5NnVoLzFvVktiZ1piM3k1Tk1mQjhoSUdJRlJZNXg2NzM5MmRmdWV1dFJw?=
 =?utf-8?B?cGdxVU9yTmhwQUdTdkpQUXlxZ1VrZnRLbW1UUm00OElHNStTYThEbVozc1RD?=
 =?utf-8?B?VlFuK0Q2SUU0WmFWSFpzNWtaajNPSUY2Nk04bEVLdzQ3dU1CM29lSTRuUjR6?=
 =?utf-8?B?TzdIcnNzY2xENmtyb2xDTEtGbzc1Ky9xQXYvdEErczRGcVlXUEdyK1JnNTJy?=
 =?utf-8?B?N1U5alFpbTNGMnNrS3BaajRSeUJEZE4zR3NUVmQ1em5CZlB0VmZPYkxnM0ND?=
 =?utf-8?B?eFNJWUp4dWVMT3VTS2p1K0NCMVlIclF6dnhhN1duZUtSajlkbDlra3l3MmVM?=
 =?utf-8?B?ODlLSS8vV2s2ZFVLWFFmdjIvRUFMdTlKM0lNUkRXMVBEbXlkdVRXeUpXTldI?=
 =?utf-8?B?c2ZtWlc5Ti90OG11VTVROW42L01PNlBPdTlhZGcrVEt0Q1F0M1ZTdDFBMnhv?=
 =?utf-8?B?VzhVMk1Ya254bGNBZWJzV2EvVjFMS25XQTJtVU03L0M5YXVQV20zV0J5QnA3?=
 =?utf-8?B?a0NIcGU4Z3NpOGwxTGVYTmlyTW5tRnRFYS9HMU9HV0g2bDNaRzh6WGd6bVUw?=
 =?utf-8?B?ZlZHQVNDNXZiQkE1SEVleEZ1dlMzdUExU0lsaWpTdWh1SjRvV1E1UmU5ZEJB?=
 =?utf-8?B?WEZKeEQyR2VHUndpTkNxeWFDZkdxQjVLOCtzdC9pN2xUZEF1WStmemtIN2Zl?=
 =?utf-8?B?ZTVZY1hOMTdaSUMzWkxpMGdxOS9WcTA0RUo4TXg2WFc5cmlCK0FNR0JyUXk4?=
 =?utf-8?Q?xfS9bYkmKj7AE4GQBA1nK2dyr?=
X-OriginatorOrg: amd.com
X-MS-Exchange-CrossTenant-Network-Message-Id: fcfa0864-37f7-4d6d-34dc-08dbdbb81871
X-MS-Exchange-CrossTenant-AuthSource: MN0PR12MB6101.namprd12.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Nov 2023 15:26:33.5035
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: JVKyBNk10PittUy9j44v1PVAh+dQAO5/reHI/yzqOJklUvrtkL9Oe3wNjneFMCp0xCRMARKcNFEbCmmX8NpAJA==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV3PR12MB9412
X-Spam-Status: No, score=-1.5 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,
        DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FORGED_SPF_HELO,
        RCVD_IN_DNSWL_BLOCKED,RCVD_IN_MSPIKE_H2,SPF_HELO_PASS,SPF_NONE,
        T_SCC_BODY_TEXT_LINE,URIBL_BLOCKED autolearn=no autolearn_force=no
        version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
        lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Thu, 02 Nov 2023 08:26:50 -0700 (PDT)

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.
> 
> Thanks,
> 
> Lukas

It's only for a device connected to an Intel TBT3 controller though; it 
won't apply to USB4.