Re: [PATCH RFC v2 03/10] dt-bindings: arm: Add MPAM MSC binding

[Andre Przywara <andre.przywara@arm.com>]

Hi,

On 9/14/26 16:41, Andre Przywara wrote:
> Hi,
> 
> On 9/14/26 11:37, Yin Li wrote:
>> From: Rob Herring <robh@kernel.org>
>>
>> The binding is designed around the assumption that an MSC will be a
>> sub-block of something else such as a memory controller, cache 
>> controller,
>> or IOMMU. However, it's certainly possible a design does not have that
>> association or has a mixture of both, so the binding illustrates how 
>> we can
>> support that with RIS child nodes.
>>
>> A key part of MPAM is we need to know about all of the MSCs in the system
>> before it can be enabled. This drives the need for the genericish
>> 'arm,mpam-msc' compatible. Though we can't assume an MSC is accessible
>> until a h/w specific driver potentially enables the h/w.
>>
>> Cc: James Morse <james.morse@arm.com>
>> Signed-off-by: Rob Herring <robh@kernel.org>
>> Signed-off-by: James Morse <james.morse@arm.com>
>> Signed-off-by: Yin Li <yin.li@oss.qualcomm.com>
>> ---
>>   .../devicetree/bindings/arm/arm,mpam-msc.yaml      | 199 +++++++++++ 
>> ++++++++++
>>   1 file changed, 199 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/arm/arm,mpam-msc.yaml 
>> b/Documentation/devicetree/bindings/arm/arm,mpam-msc.yaml
>> new file mode 100644
>> index 000000000000..53a6fdbbf05f
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/arm/arm,mpam-msc.yaml
>> @@ -0,0 +1,199 @@
>> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/arm/arm,mpam-msc.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: Arm Memory System Resource Partitioning and Monitoring (MPAM)
>> +
>> +description: |
>> +  The Arm MPAM specification can be found here:
>> +
>> +  https://developer.arm.com/documentation/ddi0598/latest
>> +
>> +maintainers:
>> +  - Rob Herring <robh@kernel.org>
>> +
>> +properties:
>> +  compatible:
>> +    items:
>> +      - const: arm,mpam-msc                   # Further details are 
>> discoverable
>> +      - const: arm,mpam-memory-controller-msc
> 
> But that doesn't match the examples below, does it? Don't we want to 
> allow just "arm,mpam-msc", but also the memory controller string, with 
> "arm,mpam-msc" as a fallback?
> I guess the pattern should then look similar to interrupt-names below?

Just seeing that you fix this and other things up in patch 08/10 later.
I think it's confusing to have this split now for a v2 still. I wouldn't 
be aware of previous review of this original patch, so it doesn't really 
matter. Please squash them.

So I think you should merge 07/10 and 08/10 into their original patches, 
otherwise reviewers might just get confused.

But you might wait for a bit with a repost, to see if there are more 
generic comments on DT support.

Cheers,
Andre