perf: arm_pmu: Move PMUv3-specific data

A few fields in struct arm_pmu are only used with PMUv3, and soon we
will need to add more for BRBE. Group the fields together so that we
have a logical place to add more data in future.

At the same time, remove the comment for reg_pmmir as it doesn't convey
anything useful.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Tested-by: James Clark <james.clark@linaro.org>
Link: https://lore.kernel.org/r/20250218-arm-brbe-v19-v20-7-4e9922fc2e8e@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

include/linux/perf/arm_pmu.h

@@ -84,7 +84,6 @@ struct arm_pmu {
 	struct pmu	pmu;
 	cpumask_t	supported_cpus;
 	char		*name;
-	int		pmuver;
 	irqreturn_t	(*handle_irq)(struct arm_pmu *pmu);
 	void		(*enable)(struct perf_event *event);
 	void		(*disable)(struct perf_event *event);
@@ -102,18 +101,20 @@ struct arm_pmu {
 	int		(*map_event)(struct perf_event *event);
 	DECLARE_BITMAP(cntr_mask, ARMPMU_MAX_HWEVENTS);
 	bool		secure_access; /* 32-bit ARM only */
-#define ARMV8_PMUV3_MAX_COMMON_EVENTS		0x40
-	DECLARE_BITMAP(pmceid_bitmap, ARMV8_PMUV3_MAX_COMMON_EVENTS);
-#define ARMV8_PMUV3_EXT_COMMON_EVENT_BASE	0x4000
-	DECLARE_BITMAP(pmceid_ext_bitmap, ARMV8_PMUV3_MAX_COMMON_EVENTS);
 	struct platform_device	*plat_device;
 	struct pmu_hw_events	__percpu *hw_events;
 	struct hlist_node	node;
 	struct notifier_block	cpu_pm_nb;
 	/* the attr_groups array must be NULL-terminated */
 	const struct attribute_group *attr_groups[ARMPMU_NR_ATTR_GROUPS + 1];
-	/* store the PMMIR_EL1 to expose slots */
+
+	/* PMUv3 only */
+	int		pmuver;
 	u64		reg_pmmir;
+#define ARMV8_PMUV3_MAX_COMMON_EVENTS		0x40
+	DECLARE_BITMAP(pmceid_bitmap, ARMV8_PMUV3_MAX_COMMON_EVENTS);
+#define ARMV8_PMUV3_EXT_COMMON_EVENT_BASE	0x4000
+	DECLARE_BITMAP(pmceid_ext_bitmap, ARMV8_PMUV3_MAX_COMMON_EVENTS);
 
 	/* Only to be used by ACPI probing code */
 	unsigned long acpi_cpuid;