arm64: Performance counters support

This patch adds support for the AArch64 performance counters.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>

1 files changed, 82 insertions, 0 deletions

diff --git a/arch/arm64/include/asm/pmu.h b/arch/arm64/include/asm/pmu.h
new file mode 100644
index 000000000000..e6f087806aaf
--- /dev/null
+++ b/arch/arm64/include/asm/pmu.h
@@ -0,0 +1,82 @@
+/*
+ * Based on arch/arm/include/asm/pmu.h
+ *
+ * Copyright (C) 2009 picoChip Designs Ltd, Jamie Iles
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_PMU_H
+#define __ASM_PMU_H
+
+#ifdef CONFIG_HW_PERF_EVENTS
+
+/* The events for a given PMU register set. */
+struct pmu_hw_events {
+        /*
+         * The events that are active on the PMU for the given index.
+         */
+        struct perf_event       **events;
+
+        /*
+         * A 1 bit for an index indicates that the counter is being used for
+         * an event. A 0 means that the counter can be used.
+         */
+        unsigned long           *used_mask;
+
+        /*
+         * Hardware lock to serialize accesses to PMU registers. Needed for the
+         * read/modify/write sequences.
+         */
+        raw_spinlock_t          pmu_lock;
+};
+
+struct arm_pmu {
+        struct pmu              pmu;
+        cpumask_t               active_irqs;
+        const char              *name;
+        irqreturn_t             (*handle_irq)(int irq_num, void *dev);
+        void                    (*enable)(struct hw_perf_event *evt, int idx);
+        void                    (*disable)(struct hw_perf_event *evt, int idx);
+        int                     (*get_event_idx)(struct pmu_hw_events *hw_events,
+                                                 struct hw_perf_event *hwc);
+        int                     (*set_event_filter)(struct hw_perf_event *evt,
+                                                    struct perf_event_attr *attr);
+        u32                     (*read_counter)(int idx);
+        void                    (*write_counter)(int idx, u32 val);
+        void                    (*start)(void);
+        void                    (*stop)(void);
+        void                    (*reset)(void *);
+        int                     (*map_event)(struct perf_event *event);
+        int                     num_events;
+        atomic_t                active_events;
+        struct mutex            reserve_mutex;
+        u64                     max_period;
+        struct platform_device  *plat_device;
+        struct pmu_hw_events    *(*get_hw_events)(void);
+};
+
+#define to_arm_pmu(p) (container_of(p, struct arm_pmu, pmu))
+
+int __init armpmu_register(struct arm_pmu *armpmu, char *name, int type);
+
+u64 armpmu_event_update(struct perf_event *event,
+                        struct hw_perf_event *hwc,
+                        int idx);
+
+int armpmu_event_set_period(struct perf_event *event,
+                            struct hw_perf_event *hwc,
+                            int idx);
+
+#endif /* CONFIG_HW_PERF_EVENTS */
+#endif /* __ASM_PMU_H */