arm64: pmuv3: handle !PMUv3 when probing

[karo-tx-linux.git] / arch / arm64 / kernel / perf_event.c

diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c
index 57ae9d9ed9bb666e5bd20698f9dce2d1f25d731f..53f235465fc48b48663f0155e599e015e50dda5e 100644 (file)
--- a/arch/arm64/kernel/perf_event.c
+++ b/arch/arm64/kernel/perf_event.c
@@ -957,11 +957,26 @@ static int armv8_vulcan_map_event(struct perf_event *event)
                                ARMV8_PMU_EVTYPE_EVENT);
 }
 
+struct armv8pmu_probe_info {
+       struct arm_pmu *pmu;
+       bool present;
+};
+
 static void __armv8pmu_probe_pmu(void *info)
 {
-       struct arm_pmu *cpu_pmu = info;
+       struct armv8pmu_probe_info *probe = info;
+       struct arm_pmu *cpu_pmu = probe->pmu;
+       u64 dfr0, pmuver;
        u32 pmceid[2];
 
+       dfr0 = read_sysreg(id_aa64dfr0_el1);
+       pmuver = cpuid_feature_extract_unsigned_field(dfr0,
+                       ID_AA64DFR0_PMUVER_SHIFT);
+       if (pmuver != 1)
+               return;
+
+       probe->present = true;
+
        /* Read the nb of CNTx counters supported from PMNC */
        cpu_pmu->num_events = (armv8pmu_pmcr_read() >> ARMV8_PMU_PMCR_N_SHIFT)
                & ARMV8_PMU_PMCR_N_MASK;
@@ -979,13 +994,27 @@ static void __armv8pmu_probe_pmu(void *info)
 
 static int armv8pmu_probe_pmu(struct arm_pmu *cpu_pmu)
 {
-       return smp_call_function_any(&cpu_pmu->supported_cpus,
+       struct armv8pmu_probe_info probe = {
+               .pmu = cpu_pmu,
+               .present = false,
+       };
+       int ret;
+
+       ret = smp_call_function_any(&cpu_pmu->supported_cpus,
                                    __armv8pmu_probe_pmu,
-                                   cpu_pmu, 1);
+                                   &probe, 1);
+       if (ret)
+               return ret;
+
+       return probe.present ? 0 : -ENODEV;
 }
 
-static void armv8_pmu_init(struct arm_pmu *cpu_pmu)
+static int armv8_pmu_init(struct arm_pmu *cpu_pmu)
 {
+       int ret = armv8pmu_probe_pmu(cpu_pmu);
+       if (ret)
+               return ret;
+
        cpu_pmu->handle_irq             = armv8pmu_handle_irq,
        cpu_pmu->enable                 = armv8pmu_enable_event,
        cpu_pmu->disable                = armv8pmu_disable_event,
@@ -997,78 +1026,104 @@ static void armv8_pmu_init(struct arm_pmu *cpu_pmu)
        cpu_pmu->reset                  = armv8pmu_reset,
        cpu_pmu->max_period             = (1LLU << 32) - 1,
        cpu_pmu->set_event_filter       = armv8pmu_set_event_filter;
+
+       return 0;
 }
 
 static int armv8_pmuv3_init(struct arm_pmu *cpu_pmu)
 {
-       armv8_pmu_init(cpu_pmu);
+       int ret = armv8_pmu_init(cpu_pmu);
+       if (ret)
+               return ret;
+
        cpu_pmu->name                   = "armv8_pmuv3";
        cpu_pmu->map_event              = armv8_pmuv3_map_event;
        cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_EVENTS] =
                &armv8_pmuv3_events_attr_group;
        cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_FORMATS] =
                &armv8_pmuv3_format_attr_group;
-       return armv8pmu_probe_pmu(cpu_pmu);
+
+       return 0;
 }
 
 static int armv8_a53_pmu_init(struct arm_pmu *cpu_pmu)
 {
-       armv8_pmu_init(cpu_pmu);
+       int ret = armv8_pmu_init(cpu_pmu);
+       if (ret)
+               return ret;
+
        cpu_pmu->name                   = "armv8_cortex_a53";
        cpu_pmu->map_event              = armv8_a53_map_event;
        cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_EVENTS] =
                &armv8_pmuv3_events_attr_group;
        cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_FORMATS] =
                &armv8_pmuv3_format_attr_group;
-       return armv8pmu_probe_pmu(cpu_pmu);
+
+       return 0;
 }
 
 static int armv8_a57_pmu_init(struct arm_pmu *cpu_pmu)
 {
-       armv8_pmu_init(cpu_pmu);
+       int ret = armv8_pmu_init(cpu_pmu);
+       if (ret)
+               return ret;
+
        cpu_pmu->name                   = "armv8_cortex_a57";
        cpu_pmu->map_event              = armv8_a57_map_event;
        cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_EVENTS] =
                &armv8_pmuv3_events_attr_group;
        cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_FORMATS] =
                &armv8_pmuv3_format_attr_group;
-       return armv8pmu_probe_pmu(cpu_pmu);
+
+       return 0;
 }
 
 static int armv8_a72_pmu_init(struct arm_pmu *cpu_pmu)
 {
-       armv8_pmu_init(cpu_pmu);
+       int ret = armv8_pmu_init(cpu_pmu);
+       if (ret)
+               return ret;
+
        cpu_pmu->name                   = "armv8_cortex_a72";
        cpu_pmu->map_event              = armv8_a57_map_event;
        cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_EVENTS] =
                &armv8_pmuv3_events_attr_group;
        cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_FORMATS] =
                &armv8_pmuv3_format_attr_group;
-       return armv8pmu_probe_pmu(cpu_pmu);
+
+       return 0;
 }
 
 static int armv8_thunder_pmu_init(struct arm_pmu *cpu_pmu)
 {
-       armv8_pmu_init(cpu_pmu);
+       int ret = armv8_pmu_init(cpu_pmu);
+       if (ret)
+               return ret;
+
        cpu_pmu->name                   = "armv8_cavium_thunder";
        cpu_pmu->map_event              = armv8_thunder_map_event;
        cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_EVENTS] =
                &armv8_pmuv3_events_attr_group;
        cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_FORMATS] =
                &armv8_pmuv3_format_attr_group;
-       return armv8pmu_probe_pmu(cpu_pmu);
+
+       return 0;
 }
 
 static int armv8_vulcan_pmu_init(struct arm_pmu *cpu_pmu)
 {
-       armv8_pmu_init(cpu_pmu);
+       int ret = armv8_pmu_init(cpu_pmu);
+       if (ret)
+               return ret;
+
        cpu_pmu->name                   = "armv8_brcm_vulcan";
        cpu_pmu->map_event              = armv8_vulcan_map_event;
        cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_EVENTS] =
                &armv8_pmuv3_events_attr_group;
        cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_FORMATS] =
                &armv8_pmuv3_format_attr_group;
-       return armv8pmu_probe_pmu(cpu_pmu);
+
+       return 0;
 }
 
 static const struct of_device_id armv8_pmu_of_device_ids[] = {