[PATCH 1/5] dt-bindings: PCI: Add STM32MP25 PCIe root complex bindings

Christian Bruel christian.bruel at foss.st.com
Fri Nov 15 00:27:05 PST 2024



On 11/12/24 19:28, Bjorn Helgaas wrote:
> On Tue, Nov 12, 2024 at 05:19:21PM +0100, Christian Bruel wrote:
>> Document the bindings for STM32MP25 PCIe Controller configured in
>> root complex mode.
>> Supports 4 legacy interrupts and MSI interrupts from the ARM
>> GICv2m controller.
>>
>> Allow tuning to change payload (default 128B) thanks to the
>> st,max-payload-size entry.
>> Can also limit the Maximum Read Request Size on downstream devices to the
>> minimum possible value between 128B and 256B.
>>
>> STM32 PCIE may be in a power domain which is the case for the STM32MP25
>> based boards.
>> Supports wake# from wake-gpios
> 
>> +  st,limit-mrrs:
>> +    description: If present limit downstream MRRS to 256B
>> +    type: boolean
>> +
>> +  st,max-payload-size:
>> +    description: Maximum Payload size to use
>> +    $ref: /schemas/types.yaml#/definitions/uint32
>> +    enum: [128, 256]
>> +    default: 128
> 
> MRRS and MPS are not specific to this device.  Not sure why you need
> them, but if you do need them, I think they should be generic.

Agree. On a second thought, this was to fix an old errata and can be 
dropped now, as well as the associated quirks.

Will re-post as generic if needed later on

thanks,

Christian



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