Re: [PATCH v6 10/10] arm_mpam: detect and enable MPAM-Fb PCC support

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

Hi Ben,

On 7/30/26 18:13, Ben Horgan wrote:
> Hi Andre,
> 
> On 7/30/26 16:25, Andre Przywara wrote:
>> The Arm MPAM-Fb specification [1] describes a protocol to access MSC
>> registers through a firmware interface. This requires a shared memory
>> region to hold the message, and a mailbox to trigger the access.
>> For ACPI this is wrapped as a PCC channel, described using existing
>> ACPI abstractions.
>>
>> Add code to parse those PCC table descriptions associated with an MSC,
>> and store the parsed information in the MSC struct.
>> There can be multiple PCC channels, and each channel can serve multiple
>> MSCs, so we need to keep track of the channel usage, using a list and
>> a refcount.
>>
>> This will be used by the MPAM-Fb access wrapper code.
>>
>> [1] https://developer.arm.com/documentation/den0144/latest
>>
>> Signed-off-by: Andre Przywara <andre.przywara@arm.com>
>> Tested-by: Ritwick Sharma <ritwick.sharma@arm.com>
> Ritwick gave his Tested-by for the series on v5. Any reason to just add the tag on this patch?

submitting-patches.rst says:
"Both Tested-by and Reviewed-by tags, once received on mailing list from 
tester or reviewer, should be added by author to the *applicable* 
patches when sending next versions."

I think this system relies on MPAM-Fb, so he couldn't test each patch in 
isolation, but "just" that MPAM-Fb works, which is what only patch 10/10 
enables.

So I find tags given for the whole series always tricky to handle, but 
in this case I figured patch 10/10 would be the right target.

> I guess patch 9 has significant enough changes to drop tags but I don't see it for the others.

Well, even smaller changes could ruin a whole thing, but IIUC in this 
case Ritwick's setup doesn't even enable error IRQs, so this part wasn't 
tested anyway.

Cheers,
Andre.