[RFC PATCH 25/36] arm_mpam: Register and enable IRQs

[James Morse]

Hi Ben,

On 28/07/2025 11:49, Ben Horgan wrote:
> On 7/11/25 19:36, James Morse wrote:
>> Register and enable error IRQs. All the MPAM error interrupts indicate a
>> software bug, e.g. out of range partid. If the error interrupt is ever
>> signalled, attempt to disable MPAM.
>>
>> Only the irq handler accesses the ESR register, so no locking is needed.
>> The work to disable MPAM after an error needs to happen at process
>> context, use a threaded interrupt.
>>
>> There is no support for percpu threaded interrupts, for now schedule
>> the work to be done from the irq handler.
>>
>> Enabling the IRQs in the MSC may involve cross calling to a CPU that
>> can access the MSC.
>> diff --git a/drivers/platform/arm64/mpam/mpam_devices.c b/drivers/platform/arm64/mpam/
>> mpam_devices.c
>> index 145535cd4732..af19cc25d16e 100644
>> --- a/drivers/platform/arm64/mpam/mpam_devices.c
>> +++ b/drivers/platform/arm64/mpam/mpam_devices.c
>> @@ -1548,11 +1638,193 @@ static void mpam_enable_merge_features(struct list_head

>> +static int mpam_enable_msc_ecr(void *_msc)
>> +{
>> +    struct mpam_msc *msc = _msc;
>> +
>> +    __mpam_write_reg(msc, MPAMF_ECR, 1);
> You can use MPAMF_ECR_INTEN.

Sure,


>> +
>> +    return 0;
>> +}

>> @@ -1644,7 +1939,6 @@ void mpam_enable(struct work_struct *work)
>>       struct mpam_msc *msc;
>>       bool all_devices_probed = true;
>>   -    /* Have we probed all the hw devices? */
> Stray change. Keep the comment or remove it in the patch that introduced it.

Fixed.


Thanks,

James