Re: [PATCH v2 2/4] thunderbolt: Separate out common NHI bits

[Konrad Dybcio]

On 5/12/26 3:20 PM, Mika Westerberg wrote:
> On Tue, May 12, 2026 at 03:06:58PM +0200, Konrad Dybcio wrote:
>> On 5/4/26 8:54 AM, Mika Westerberg wrote:
>>> Hi,

[...]

>>>> +/*
>>>> + * During suspend the Thunderbolt controller is reset and all PCIe
>>>> + * tunnels are lost. The NHI driver will try to reestablish all tunnels
>>>> + * during resume. This adds device links between the tunneled PCIe
>>>> + * downstream ports and the NHI so that the device core will make sure
>>>> + * NHI is resumed first before the rest.
>>>> + */
>>>> +bool tb_apple_add_links(struct tb_nhi *nhi)
>>>
>>> Okay you moved it here good. I think we can call it in nhi_pci_probe()
>>> directly so no need to expose outside.
>>
>> Yeah that seems like a good idea. It's already there, behind N calls
>> in the software CM case.
>>
>> Do we have to check the CM type though, or do you think it'd be fine
>> to just call it unconditionally? (either because there are presumably
>> no Apple machines with ICM or because these devlinks would be harmless?)
> 
> I think you can call it unconditionally. It only does something for TB1-2
> Apple systems.
> 
> For Apple TB3 we used to start ICM firmware but this was changed as the
> driver learned SW CM. However, we never setup any device links so this
> would not change anything.

OK. I'm keeping tb_acpi_add_link() as-is, since that's both bus- and
arch-independent.

However, doing just something like:

diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c
index cb5d028de3bc..f5ddc8ddb8bb 100644
--- a/drivers/thunderbolt/tb.c
+++ b/drivers/thunderbolt/tb.c
@@ -3327,7 +3327,7 @@ struct tb *tb_probe(struct tb_nhi *nhi)
         * before the PCIe/USB stack is resumed so complain here if we
         * found them missing.
         */
-       if (!tb_apple_add_links(nhi) && !tb_acpi_add_links(nhi))
+       if (!tb_acpi_add_links(nhi))
                tb_warn(tb, "device links to tunneled native ports are missing!\n");


diff --git a/drivers/thunderbolt/pci.c b/drivers/thunderbolt/pci.c
index ca50e3584cac..e0abd1d503c5 100644
--- a/drivers/thunderbolt/pci.c
+++ b/drivers/thunderbolt/pci.c
@@ -294,6 +294,8 @@ static int nhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 
        pci_set_master(pdev);
 
+       tb_apple_add_links(nhi)
+
        return nhi_probe(&nhi_pci->nhi);
 }


Will cause the warning to show up. And adding something like
`nhi->device_links_done` is a little ugly.. Ideas?

Konrad