[PATCH 6/8] perf/arm-cmn: Refactor DTC PMU register access

Robin Murphy robin.murphy at arm.com
Mon Aug 19 09:41:30 PDT 2024


On 16/08/2024 11:29 am, Mark Rutland wrote:
> On Fri, Aug 09, 2024 at 08:15:45PM +0100, Robin Murphy wrote:
>> Annoyingly, we're soon going to have to cope with PMU registers moving
>> about. This will mostly be straightforward, except for the hard-coding
>> of CMN_PMU_OFFSET for the DTC PMU registers. As a first step, refactor
>> those accessors to allow for encapsulating a variable offset without
>> making a big mess all over.
>>
>> Signed-off-by: Robin Murphy <robin.murphy at arm.com>
>> ---
>>   drivers/perf/arm-cmn.c | 64 ++++++++++++++++++++++++------------------
>>   1 file changed, 36 insertions(+), 28 deletions(-)
> 
> Aside from a minoe comment below this looks fine to me.
> 
>>   struct arm_cmn_dtc {
>>   	void __iomem *base;
>> +	void __iomem *pmu_base;
>>   	int irq;
>> -	int irq_friend;
>> +	s8 irq_friend;
> 
> Unrelated change?
> 
> AFAICT there's no reason for 'irq_friend' to change from 'int' to 's8',
> and nothing in the commit message explains it.

Oops, I had meant to note in the commit message that this is a little 
structure repacking where there was a hole already, to compensate for 
adding the new member... I shall un-forget that for v2.

> Otherwise this all looks fine to me.

Thanks,
Robin.

> 
> Mark.



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