perf/arm_cspmu: Improve APMT-based PMU naming

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On ACPI systems, it has not actually been possible for userspace to
reliably tell which PMU corresponds to which APMT entry for types
other than "ACPI device" - the evidence trail only leads from the
arbitrarily-numbered PMU device to its arbitrarily-numbered parent
platform device that has no distinguishing features either.

While we've now improved the platform device creation to associate the
actual APMT unique ID, we may as well also tweak the PMU devices to
substitute the arbitrary number with a different arbitrary number that
might be more directly meaningful based on the APMT definitions.

We don't have an equivalent for Devicetree, but in that case the
platform devices are at least identifiable via their sysfs-visible
of_node.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Ilkka Koskinen <ilkka@os.amperecomputing.com>
[will: Remove unneeded semicolon reported by coccinelle]
Signed-off-by: Will Deacon <will@kernel.org>

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Robin Murphy 2026-07-16 15:56:35 +01:00 • committed by Will Deacon

parent 04aa909b38

commit 745a724f9c

1 changed files with 19 additions and 14 deletions

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drivers/perf/arm_cspmu/arm_cspmu.c

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