Re: [PATCH v2 6/7] dt-bindings: PCI: intel,lgm-pcie: Make atu resource mandatory

[Florian Eckert <fe@dev.tdt.de>]

On 2026-03-31 17:21, Rob Herring wrote:
> On Mon, Mar 30, 2026 at 11:07:16AM +0200, Florian Eckert wrote:
>> The ATU information is already set in the dwc core if it is specified 
>> in
>> the DTS. The driver uses its own value here [1]. This information is
>> hardware specific and should therefore be maintained in the DTS rather
>> than in the source.
>> 
>> Backwards compatibility is not an issue here [5], as the driver is
>> exclusively used by Maxlinear.
>> 
>> Old DTS entry for PCIe:
>> 
>> reg = <0xd1000000 0x1000>,
>>       <0xd3000000 0x20000>,
>>       <0xd0c41000.0x1000>;
>> reg-names = "dbi", "config", "app";
>> 
>> New DTS entry for PCIe:
>> 
>> reg = <0xd1000000 0x1000>,
>>       <0xd10c0000 0x1000>,
>>       <0xd3000000 0x20000>,
>>      <0xd0c41000.0x1000>;
>> reg-names = "dbi", "atu", "config", "app";
>> 
>> [1] 
>> https://elixir.bootlin.com/linux/v6.19.10/source/drivers/pci/controller/dwc/pcie-intel-gw.c#L301
>> [2] 
>> https://lore.kernel.org/all/BY3PR19MB507667CE7531D863E1E5F8AEBDD82@BY3PR19MB5076.namprd19.prod.outlook.com/
>> 
>> Signed-off-by: Florian Eckert <fe@dev.tdt.de>
>> ---
>>  Documentation/devicetree/bindings/pci/intel-gw-pcie.yaml | 5 ++++-
>>  1 file changed, 4 insertions(+), 1 deletion(-)
>> 
>> diff --git a/Documentation/devicetree/bindings/pci/intel-gw-pcie.yaml 
>> b/Documentation/devicetree/bindings/pci/intel-gw-pcie.yaml
>> index 
>> 54e2890ae6314ac6847fc23f49440d05d66d87d4..e4b781f57e8ae84a3ffc33635a421e1a5761587e 
>> 100644
>> --- a/Documentation/devicetree/bindings/pci/intel-gw-pcie.yaml
>> +++ b/Documentation/devicetree/bindings/pci/intel-gw-pcie.yaml
>> @@ -29,12 +29,14 @@ properties:
>>    reg:
>>      items:
>>        - description: Controller control and status registers.
>> +      - description: Internal Address Translation Unit (iATU) 
>> registers.
>>        - description: PCIe configuration registers.
>>        - description: Controller application registers.
>> 
>>    reg-names:
>>      items:
>>        - const: dbi
>> +      - const: atu
> 
> Put this at the end and add 'minItems: 3' and you avoid any ABI issues.

Unfortunately, I misunderstood what you meant. This is still wrong in v3 
[1]
I send to day. I’ve only changed it in the documentation. I forgot to do
that in the example, as I didn’t realize that we can not always access
resources by name, but also by index. That’s why the order matters. I’ve 
got
it now.

Thanks!

My mistake – I’ll change that in v4 tomorrow so that your bot is happy 
too.

--
Florian

[1] 
https://lore.kernel.org/all/20260401-pcie-intel-gw-v3-0-63b008c5b7b2@dev.tdt.de/T/#t

> 
>>        - const: config
>>        - const: app
>>