2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License version 2 as
4 * published by the Free Software Foundation.
6 * This program is distributed in the hope that it will be useful,
7 * but WITHOUT ANY WARRANTY; without even the implied warranty of
8 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
9 * GNU General Public License for more details.
11 * You should have received a copy of the GNU General Public License
12 * along with this program; if not, write to the Free Software
13 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
15 * Copyright (C) 2012 ARM Limited
17 * Author: Will Deacon <will.deacon@arm.com>
19 #define pr_fmt(fmt) "CPU PMU: " fmt
21 #include <linux/bitmap.h>
22 #include <linux/export.h>
23 #include <linux/kernel.h>
25 #include <linux/platform_device.h>
26 #include <linux/slab.h>
27 #include <linux/spinlock.h>
28 #include <linux/irq.h>
29 #include <linux/irqdesc.h>
31 #include <asm/cputype.h>
32 #include <asm/irq_regs.h>
35 /* Set at runtime when we know what CPU type we are. */
36 static struct arm_pmu *cpu_pmu;
38 static DEFINE_PER_CPU(struct arm_pmu *, percpu_pmu);
39 static DEFINE_PER_CPU(struct perf_event * [ARMPMU_MAX_HWEVENTS], hw_events);
40 static DEFINE_PER_CPU(unsigned long [BITS_TO_LONGS(ARMPMU_MAX_HWEVENTS)], used_mask);
41 static DEFINE_PER_CPU(struct pmu_hw_events, cpu_hw_events);
44 * Despite the names, these two functions are CPU-specific and are used
45 * by the OProfile/perf code.
47 const char *perf_pmu_name(void)
54 EXPORT_SYMBOL_GPL(perf_pmu_name);
56 int perf_num_counters(void)
61 max_events = cpu_pmu->num_events;
65 EXPORT_SYMBOL_GPL(perf_num_counters);
67 /* Include the PMU-specific implementations. */
68 #include "perf_event_xscale.c"
69 #include "perf_event_v6.c"
70 #include "perf_event_v7.c"
72 static struct pmu_hw_events *cpu_pmu_get_cpu_events(void)
74 return this_cpu_ptr(&cpu_hw_events);
77 static void cpu_pmu_enable_percpu_irq(void *data)
79 struct arm_pmu *cpu_pmu = data;
80 struct platform_device *pmu_device = cpu_pmu->plat_device;
81 int irq = platform_get_irq(pmu_device, 0);
83 enable_percpu_irq(irq, IRQ_TYPE_NONE);
84 cpumask_set_cpu(smp_processor_id(), &cpu_pmu->active_irqs);
87 static void cpu_pmu_disable_percpu_irq(void *data)
89 struct arm_pmu *cpu_pmu = data;
90 struct platform_device *pmu_device = cpu_pmu->plat_device;
91 int irq = platform_get_irq(pmu_device, 0);
93 cpumask_clear_cpu(smp_processor_id(), &cpu_pmu->active_irqs);
94 disable_percpu_irq(irq);
97 static void cpu_pmu_free_irq(struct arm_pmu *cpu_pmu)
100 struct platform_device *pmu_device = cpu_pmu->plat_device;
102 irqs = min(pmu_device->num_resources, num_possible_cpus());
104 irq = platform_get_irq(pmu_device, 0);
105 if (irq >= 0 && irq_is_percpu(irq)) {
106 on_each_cpu(cpu_pmu_disable_percpu_irq, cpu_pmu, 1);
107 free_percpu_irq(irq, &percpu_pmu);
109 for (i = 0; i < irqs; ++i) {
110 if (!cpumask_test_and_clear_cpu(i, &cpu_pmu->active_irqs))
112 irq = platform_get_irq(pmu_device, i);
114 free_irq(irq, cpu_pmu);
119 static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler)
121 int i, err, irq, irqs;
122 struct platform_device *pmu_device = cpu_pmu->plat_device;
127 irqs = min(pmu_device->num_resources, num_possible_cpus());
129 pr_err("no irqs for PMUs defined\n");
133 irq = platform_get_irq(pmu_device, 0);
134 if (irq >= 0 && irq_is_percpu(irq)) {
135 err = request_percpu_irq(irq, handler, "arm-pmu", &percpu_pmu);
137 pr_err("unable to request IRQ%d for ARM PMU counters\n",
141 on_each_cpu(cpu_pmu_enable_percpu_irq, cpu_pmu, 1);
143 for (i = 0; i < irqs; ++i) {
145 irq = platform_get_irq(pmu_device, i);
150 * If we have a single PMU interrupt that we can't shift,
151 * assume that we're running on a uniprocessor machine and
152 * continue. Otherwise, continue without this interrupt.
154 if (irq_set_affinity(irq, cpumask_of(i)) && irqs > 1) {
155 pr_warning("unable to set irq affinity (irq=%d, cpu=%u)\n",
160 err = request_irq(irq, handler,
161 IRQF_NOBALANCING | IRQF_NO_THREAD, "arm-pmu",
164 pr_err("unable to request IRQ%d for ARM PMU counters\n",
169 cpumask_set_cpu(i, &cpu_pmu->active_irqs);
176 static void cpu_pmu_init(struct arm_pmu *cpu_pmu)
179 for_each_possible_cpu(cpu) {
180 struct pmu_hw_events *events = &per_cpu(cpu_hw_events, cpu);
181 events->events = per_cpu(hw_events, cpu);
182 events->used_mask = per_cpu(used_mask, cpu);
183 raw_spin_lock_init(&events->pmu_lock);
184 per_cpu(percpu_pmu, cpu) = cpu_pmu;
187 cpu_pmu->get_hw_events = cpu_pmu_get_cpu_events;
188 cpu_pmu->request_irq = cpu_pmu_request_irq;
189 cpu_pmu->free_irq = cpu_pmu_free_irq;
191 /* Ensure the PMU has sane values out of reset. */
193 on_each_cpu(cpu_pmu->reset, cpu_pmu, 1);
197 * PMU hardware loses all context when a CPU goes offline.
198 * When a CPU is hotplugged back in, since some hardware registers are
199 * UNKNOWN at reset, the PMU must be explicitly reset to avoid reading
200 * junk values out of them.
202 static int cpu_pmu_notify(struct notifier_block *b, unsigned long action,
205 if ((action & ~CPU_TASKS_FROZEN) != CPU_STARTING)
208 if (cpu_pmu && cpu_pmu->reset)
209 cpu_pmu->reset(cpu_pmu);
216 static struct notifier_block cpu_pmu_hotplug_notifier = {
217 .notifier_call = cpu_pmu_notify,
221 * PMU platform driver and devicetree bindings.
223 static struct of_device_id cpu_pmu_of_device_ids[] = {
224 {.compatible = "arm,cortex-a17-pmu", .data = armv7_a17_pmu_init},
225 {.compatible = "arm,cortex-a15-pmu", .data = armv7_a15_pmu_init},
226 {.compatible = "arm,cortex-a12-pmu", .data = armv7_a12_pmu_init},
227 {.compatible = "arm,cortex-a9-pmu", .data = armv7_a9_pmu_init},
228 {.compatible = "arm,cortex-a8-pmu", .data = armv7_a8_pmu_init},
229 {.compatible = "arm,cortex-a7-pmu", .data = armv7_a7_pmu_init},
230 {.compatible = "arm,cortex-a5-pmu", .data = armv7_a5_pmu_init},
231 {.compatible = "arm,arm11mpcore-pmu", .data = armv6mpcore_pmu_init},
232 {.compatible = "arm,arm1176-pmu", .data = armv6pmu_init},
233 {.compatible = "arm,arm1136-pmu", .data = armv6pmu_init},
234 {.compatible = "qcom,krait-pmu", .data = krait_pmu_init},
238 static struct platform_device_id cpu_pmu_plat_device_ids[] = {
244 * CPU PMU identification and probing.
246 static int probe_current_pmu(struct arm_pmu *pmu)
249 unsigned long implementor = read_cpuid_implementor();
250 unsigned long part_number = read_cpuid_part_number();
253 pr_info("probing PMU on CPU %d\n", cpu);
256 if (implementor == ARM_CPU_IMP_ARM) {
257 switch (part_number) {
258 case ARM_CPU_PART_ARM1136:
259 case ARM_CPU_PART_ARM1156:
260 case ARM_CPU_PART_ARM1176:
261 ret = armv6pmu_init(pmu);
263 case ARM_CPU_PART_ARM11MPCORE:
264 ret = armv6mpcore_pmu_init(pmu);
266 case ARM_CPU_PART_CORTEX_A8:
267 ret = armv7_a8_pmu_init(pmu);
269 case ARM_CPU_PART_CORTEX_A9:
270 ret = armv7_a9_pmu_init(pmu);
273 /* Intel CPUs [xscale]. */
274 } else if (implementor == ARM_CPU_IMP_INTEL) {
275 switch (xscale_cpu_arch_version()) {
276 case ARM_CPU_XSCALE_ARCH_V1:
277 ret = xscale1pmu_init(pmu);
279 case ARM_CPU_XSCALE_ARCH_V2:
280 ret = xscale2pmu_init(pmu);
289 static int cpu_pmu_device_probe(struct platform_device *pdev)
291 const struct of_device_id *of_id;
292 const int (*init_fn)(struct arm_pmu *);
293 struct device_node *node = pdev->dev.of_node;
298 pr_info("attempt to register multiple PMU devices!");
302 pmu = kzalloc(sizeof(struct arm_pmu), GFP_KERNEL);
304 pr_info("failed to allocate PMU device!");
309 cpu_pmu->plat_device = pdev;
311 if (node && (of_id = of_match_node(cpu_pmu_of_device_ids, pdev->dev.of_node))) {
312 init_fn = of_id->data;
315 ret = probe_current_pmu(pmu);
319 pr_info("failed to probe PMU!");
323 cpu_pmu_init(cpu_pmu);
324 ret = armpmu_register(cpu_pmu, PERF_TYPE_RAW);
330 pr_info("failed to register PMU devices!");
335 static struct platform_driver cpu_pmu_driver = {
338 .pm = &armpmu_dev_pm_ops,
339 .of_match_table = cpu_pmu_of_device_ids,
341 .probe = cpu_pmu_device_probe,
342 .id_table = cpu_pmu_plat_device_ids,
345 static int __init register_pmu_driver(void)
349 err = register_cpu_notifier(&cpu_pmu_hotplug_notifier);
353 err = platform_driver_register(&cpu_pmu_driver);
355 unregister_cpu_notifier(&cpu_pmu_hotplug_notifier);
359 device_initcall(register_pmu_driver);