Re: [PATCH] PCI/ASPM: Enable L0s/L1 for removable devices when BIOS didn't configure ASPM

[Mario Limonciello <mario.limonciello@amd.com>]

On 5/6/26 10:27, Bjorn Helgaas wrote:
> On Wed, May 06, 2026 at 10:10:47AM -0500, Mario Limonciello wrote:
>> On 5/5/26 23:53, Mika Westerberg wrote:
>>> On Tue, May 05, 2026 at 08:09:22PM +0200, Rafael J. Wysocki wrote:
>>>> On Tue, May 5, 2026 at 12:53 AM Mario Limonciello
>>>> <mario.limonciello@amd.com> wrote:
>> ...
> 
>>>>> +        * For devicetree platforms, enable L0s and L1 by default.
>>>>> +        *
>>>>> +        * For removable devices (e.g., Thunderbolt/USB4), enable L0s and L1
>>>>> +        * by default if BIOS didn't configure any ASPM states. This handles
>>>>> +        * hotplugged devices where firmware may not have configured ASPM.
>>>>> +        */
>>>
>>> Only L1 is supported over TB/USB4 tunnel (no L0s, no L1 substates). The
>>> PCIe endpoint and the downstream port it connects to of course can support
>>> the full range as that's a real PCIe link.
>>
>> OK - the comment should be updated but I do expect that below code
>> (link->aspm_support) should remain OK.
> 
> TB/USB4 are examples of removable devices but they're not the only
> ones, so I think it's OK for the comment to mention L0s.  In fact, it
> *should* mention L0s since the code below includes L0s, and mentioning
> only L1 would just be confusing.
> 
It sounds like you're suggesting no changes to this proposal then, right?