drivers/perf: arm_pmu: split out platform device probe logic

Now that we've split the pdev and DT probing logic from the runtime
management, let's move the former into its own file. We gain a few lines
due to the copyright header and includes, but this should keep the logic
clearly separated, and paves the way for adding ACPI support in a
similar fashion.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
[will: rename nr_irqs to avoid conflict with global variable]
Signed-off-by: Will Deacon <will.deacon@arm.com>

4 files changed, 247 insertions, 223 deletions

diff --git a/drivers/perf/Makefile b/drivers/perf/Makefile
index ef0c6b210345..925cd3903029 100644
--- a/drivers/perf/Makefile
+++ b/drivers/perf/Makefile
@@ -1,4 +1,4 @@
-obj-$(CONFIG_ARM_PMU) += arm_pmu.o
+obj-$(CONFIG_ARM_PMU) += arm_pmu.o arm_pmu_platform.o
 obj-$(CONFIG_QCOM_L2_PMU)       += qcom_l2_pmu.o
 obj-$(CONFIG_QCOM_L3_PMU) += qcom_l3_pmu.o
 obj-$(CONFIG_XGENE_PMU) += xgene_pmu.o
diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
index f387d6153099..b3bedfa512eb 100644
--- a/drivers/perf/arm_pmu.c
+++ b/drivers/perf/arm_pmu.c
@@ -16,7 +16,6 @@
 #include <linux/cpu_pm.h>
 #include <linux/export.h>
 #include <linux/kernel.h>
-#include <linux/of_device.h>
 #include <linux/perf/arm_pmu.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
@@ -25,7 +24,6 @@
 #include <linux/irq.h>
 #include <linux/irqdesc.h>
 
-#include <asm/cputype.h>
 #include <asm/irq_regs.h>
 
 static int
@@ -544,7 +542,7 @@ static void armpmu_free_irq(struct arm_pmu *armpmu, int cpu)
         free_irq(irq, per_cpu_ptr(&hw_events->percpu_pmu, cpu));
 }
 
-static void armpmu_free_irqs(struct arm_pmu *armpmu)
+void armpmu_free_irqs(struct arm_pmu *armpmu)
 {
         int cpu;
 
@@ -589,7 +587,7 @@ static int armpmu_request_irq(struct arm_pmu *armpmu, int cpu)
         return 0;
 }
 
-static int armpmu_request_irqs(struct arm_pmu *armpmu)
+int armpmu_request_irqs(struct arm_pmu *armpmu)
 {
         int cpu, err;
 
@@ -783,161 +781,7 @@ static void cpu_pmu_destroy(struct arm_pmu *cpu_pmu)
                                             &cpu_pmu->node);
 }
 
-/*
- * CPU PMU identification and probing.
- */
-static int probe_current_pmu(struct arm_pmu *pmu,
-                             const struct pmu_probe_info *info)
-{
-        int cpu = get_cpu();
-        unsigned int cpuid = read_cpuid_id();
-        int ret = -ENODEV;
-
-        pr_info("probing PMU on CPU %d\n", cpu);
-
-        for (; info->init != NULL; info++) {
-                if ((cpuid & info->mask) != info->cpuid)
-                        continue;
-                ret = info->init(pmu);
-                break;
-        }
-
-        put_cpu();
-        return ret;
-}
-
-static int pmu_parse_percpu_irq(struct arm_pmu *pmu, int irq)
-{
-        int cpu, ret;
-        struct pmu_hw_events __percpu *hw_events = pmu->hw_events;
-
-        ret = irq_get_percpu_devid_partition(irq, &pmu->supported_cpus);
-        if (ret)
-                return ret;
-
-        for_each_cpu(cpu, &pmu->supported_cpus)
-                per_cpu(hw_events->irq, cpu) = irq;
-
-        return 0;
-}
-
-static bool pmu_has_irq_affinity(struct device_node *node)
-{
-        return !!of_find_property(node, "interrupt-affinity", NULL);
-}
-
-static int pmu_parse_irq_affinity(struct device_node *node, int i)
-{
-        struct device_node *dn;
-        int cpu;
-
-        /*
-         * If we don't have an interrupt-affinity property, we guess irq
-         * affinity matches our logical CPU order, as we used to assume.
-         * This is fragile, so we'll warn in pmu_parse_irqs().
-         */
-        if (!pmu_has_irq_affinity(node))
-                return i;
-
-        dn = of_parse_phandle(node, "interrupt-affinity", i);
-        if (!dn) {
-                pr_warn("failed to parse interrupt-affinity[%d] for %s\n",
-                        i, node->name);
-                return -EINVAL;
-        }
-
-        /* Now look up the logical CPU number */
-        for_each_possible_cpu(cpu) {
-                struct device_node *cpu_dn;
-
-                cpu_dn = of_cpu_device_node_get(cpu);
-                of_node_put(cpu_dn);
-
-                if (dn == cpu_dn)
-                        break;
-        }
-
-        if (cpu >= nr_cpu_ids) {
-                pr_warn("failed to find logical CPU for %s\n", dn->name);
-        }
-
-        of_node_put(dn);
-
-        return cpu;
-}
-
-static int pmu_parse_irqs(struct arm_pmu *pmu)
-{
-        int i = 0, irqs;
-        struct platform_device *pdev = pmu->plat_device;
-        struct pmu_hw_events __percpu *hw_events = pmu->hw_events;
-
-        irqs = platform_irq_count(pdev);
-        if (irqs < 0) {
-                pr_err("unable to count PMU IRQs\n");
-                return irqs;
-        }
-
-        /*
-         * In this case we have no idea which CPUs are covered by the PMU.
-         * To match our prior behaviour, we assume all CPUs in this case.
-         */
-        if (irqs == 0) {
-                pr_warn("no irqs for PMU, sampling events not supported\n");
-                pmu->pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT;
-                cpumask_setall(&pmu->supported_cpus);
-                return 0;
-        }
-
-        if (irqs == 1) {
-                int irq = platform_get_irq(pdev, 0);
-                if (irq && irq_is_percpu(irq))
-                        return pmu_parse_percpu_irq(pmu, irq);
-        }
-
-        if (!pmu_has_irq_affinity(pdev->dev.of_node)) {
-                pr_warn("no interrupt-affinity property for %s, guessing.\n",
-                        of_node_full_name(pdev->dev.of_node));
-        }
-
-        /*
-         * Some platforms have all PMU IRQs OR'd into a single IRQ, with a
-         * special platdata function that attempts to demux them.
-         */
-        if (dev_get_platdata(&pdev->dev))
-                cpumask_setall(&pmu->supported_cpus);
-
-        for (i = 0; i < irqs; i++) {
-                int cpu, irq;
-
-                irq = platform_get_irq(pdev, i);
-                if (WARN_ON(irq <= 0))
-                        continue;
-
-                if (irq_is_percpu(irq)) {
-                        pr_warn("multiple PPIs or mismatched SPI/PPI detected\n");
-                        return -EINVAL;
-                }
-
-                cpu = pmu_parse_irq_affinity(pdev->dev.of_node, i);
-                if (cpu < 0)
-                        return cpu;
-                if (cpu >= nr_cpu_ids)
-                        continue;
-
-                if (per_cpu(hw_events->irq, cpu)) {
-                        pr_warn("multiple PMU IRQs for the same CPU detected\n");
-                        return -EINVAL;
-                }
-
-                per_cpu(hw_events->irq, cpu) = irq;
-                cpumask_set_cpu(cpu, &pmu->supported_cpus);
-        }
-
-        return 0;
-}
-
-static struct arm_pmu *armpmu_alloc(void)
+struct arm_pmu *armpmu_alloc(void)
 {
         struct arm_pmu *pmu;
         int cpu;
@@ -994,7 +838,7 @@ out:
         return NULL;
 }
 
-static void armpmu_free(struct arm_pmu *pmu)
+void armpmu_free(struct arm_pmu *pmu)
 {
         free_percpu(pmu->hw_events);
         kfree(pmu);
@@ -1025,68 +869,6 @@ out_destroy:
         return ret;
 }
 
-int arm_pmu_device_probe(struct platform_device *pdev,
-                         const struct of_device_id *of_table,
-                         const struct pmu_probe_info *probe_table)
-{
-        const struct of_device_id *of_id;
-        armpmu_init_fn init_fn;
-        struct device_node *node = pdev->dev.of_node;
-        struct arm_pmu *pmu;
-        int ret = -ENODEV;
-
-        pmu = armpmu_alloc();
-        if (!pmu)
-                return -ENOMEM;
-
-        pmu->plat_device = pdev;
-
-        ret = pmu_parse_irqs(pmu);
-        if (ret)
-                goto out_free;
-
-        if (node && (of_id = of_match_node(of_table, pdev->dev.of_node))) {
-                init_fn = of_id->data;
-
-                pmu->secure_access = of_property_read_bool(pdev->dev.of_node,
-                                                           "secure-reg-access");
-
-                /* arm64 systems boot only as non-secure */
-                if (IS_ENABLED(CONFIG_ARM64) && pmu->secure_access) {
-                        pr_warn("ignoring \"secure-reg-access\" property for arm64\n");
-                        pmu->secure_access = false;
-                }
-
-                ret = init_fn(pmu);
-        } else if (probe_table) {
-                cpumask_setall(&pmu->supported_cpus);
-                ret = probe_current_pmu(pmu, probe_table);
-        }
-
-        if (ret) {
-                pr_info("%s: failed to probe PMU!\n", of_node_full_name(node));
-                goto out_free;
-        }
-
-        ret = armpmu_request_irqs(pmu);
-        if (ret)
-                goto out_free_irqs;
-
-        ret = armpmu_register(pmu);
-        if (ret)
-                goto out_free;
-
-        return 0;
-
-out_free_irqs:
-        armpmu_free_irqs(pmu);
-out_free:
-        pr_info("%s: failed to register PMU devices!\n",
-                of_node_full_name(node));
-        armpmu_free(pmu);
-        return ret;
-}
-
 static int arm_pmu_hp_init(void)
 {
         int ret;
diff --git a/drivers/perf/arm_pmu_platform.c b/drivers/perf/arm_pmu_platform.c
new file mode 100644
index 000000000000..69255f53057a
--- /dev/null
+++ b/drivers/perf/arm_pmu_platform.c
@@ -0,0 +1,235 @@
+/*
+ * platform_device probing code for ARM performance counters.
+ *
+ * Copyright (C) 2009 picoChip Designs, Ltd., Jamie Iles
+ * Copyright (C) 2010 ARM Ltd., Will Deacon <will.deacon@arm.com>
+ */
+#define pr_fmt(fmt) "hw perfevents: " fmt
+
+#include <linux/bug.h>
+#include <linux/cpumask.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/irq.h>
+#include <linux/irqdesc.h>
+#include <linux/kconfig.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/percpu.h>
+#include <linux/perf/arm_pmu.h>
+#include <linux/platform_device.h>
+#include <linux/printk.h>
+#include <linux/smp.h>
+
+static int probe_current_pmu(struct arm_pmu *pmu,
+                             const struct pmu_probe_info *info)
+{
+        int cpu = get_cpu();
+        unsigned int cpuid = read_cpuid_id();
+        int ret = -ENODEV;
+
+        pr_info("probing PMU on CPU %d\n", cpu);
+
+        for (; info->init != NULL; info++) {
+                if ((cpuid & info->mask) != info->cpuid)
+                        continue;
+                ret = info->init(pmu);
+                break;
+        }
+
+        put_cpu();
+        return ret;
+}
+
+static int pmu_parse_percpu_irq(struct arm_pmu *pmu, int irq)
+{
+        int cpu, ret;
+        struct pmu_hw_events __percpu *hw_events = pmu->hw_events;
+
+        ret = irq_get_percpu_devid_partition(irq, &pmu->supported_cpus);
+        if (ret)
+                return ret;
+
+        for_each_cpu(cpu, &pmu->supported_cpus)
+                per_cpu(hw_events->irq, cpu) = irq;
+
+        return 0;
+}
+
+static bool pmu_has_irq_affinity(struct device_node *node)
+{
+        return !!of_find_property(node, "interrupt-affinity", NULL);
+}
+
+static int pmu_parse_irq_affinity(struct device_node *node, int i)
+{
+        struct device_node *dn;
+        int cpu;
+
+        /*
+         * If we don't have an interrupt-affinity property, we guess irq
+         * affinity matches our logical CPU order, as we used to assume.
+         * This is fragile, so we'll warn in pmu_parse_irqs().
+         */
+        if (!pmu_has_irq_affinity(node))
+                return i;
+
+        dn = of_parse_phandle(node, "interrupt-affinity", i);
+        if (!dn) {
+                pr_warn("failed to parse interrupt-affinity[%d] for %s\n",
+                        i, node->name);
+                return -EINVAL;
+        }
+
+        /* Now look up the logical CPU number */
+        for_each_possible_cpu(cpu) {
+                struct device_node *cpu_dn;
+
+                cpu_dn = of_cpu_device_node_get(cpu);
+                of_node_put(cpu_dn);
+
+                if (dn == cpu_dn)
+                        break;
+        }
+
+        if (cpu >= nr_cpu_ids) {
+                pr_warn("failed to find logical CPU for %s\n", dn->name);
+        }
+
+        of_node_put(dn);
+
+        return cpu;
+}
+
+static int pmu_parse_irqs(struct arm_pmu *pmu)
+{
+        int i = 0, num_irqs;
+        struct platform_device *pdev = pmu->plat_device;
+        struct pmu_hw_events __percpu *hw_events = pmu->hw_events;
+
+        num_irqs = platform_irq_count(pdev);
+        if (num_irqs < 0) {
+                pr_err("unable to count PMU IRQs\n");
+                return num_irqs;
+        }
+
+        /*
+         * In this case we have no idea which CPUs are covered by the PMU.
+         * To match our prior behaviour, we assume all CPUs in this case.
+         */
+        if (num_irqs == 0) {
+                pr_warn("no irqs for PMU, sampling events not supported\n");
+                pmu->pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT;
+                cpumask_setall(&pmu->supported_cpus);
+                return 0;
+        }
+
+        if (num_irqs == 1) {
+                int irq = platform_get_irq(pdev, 0);
+                if (irq && irq_is_percpu(irq))
+                        return pmu_parse_percpu_irq(pmu, irq);
+        }
+
+        if (!pmu_has_irq_affinity(pdev->dev.of_node)) {
+                pr_warn("no interrupt-affinity property for %s, guessing.\n",
+                        of_node_full_name(pdev->dev.of_node));
+        }
+
+        /*
+         * Some platforms have all PMU IRQs OR'd into a single IRQ, with a
+         * special platdata function that attempts to demux them.
+         */
+        if (dev_get_platdata(&pdev->dev))
+                cpumask_setall(&pmu->supported_cpus);
+
+        for (i = 0; i < num_irqs; i++) {
+                int cpu, irq;
+
+                irq = platform_get_irq(pdev, i);
+                if (WARN_ON(irq <= 0))
+                        continue;
+
+                if (irq_is_percpu(irq)) {
+                        pr_warn("multiple PPIs or mismatched SPI/PPI detected\n");
+                        return -EINVAL;
+                }
+
+                cpu = pmu_parse_irq_affinity(pdev->dev.of_node, i);
+                if (cpu < 0)
+                        return cpu;
+                if (cpu >= nr_cpu_ids)
+                        continue;
+
+                if (per_cpu(hw_events->irq, cpu)) {
+                        pr_warn("multiple PMU IRQs for the same CPU detected\n");
+                        return -EINVAL;
+                }
+
+                per_cpu(hw_events->irq, cpu) = irq;
+                cpumask_set_cpu(cpu, &pmu->supported_cpus);
+        }
+
+        return 0;
+}
+
+int arm_pmu_device_probe(struct platform_device *pdev,
+                         const struct of_device_id *of_table,
+                         const struct pmu_probe_info *probe_table)
+{
+        const struct of_device_id *of_id;
+        armpmu_init_fn init_fn;
+        struct device_node *node = pdev->dev.of_node;
+        struct arm_pmu *pmu;
+        int ret = -ENODEV;
+
+        pmu = armpmu_alloc();
+        if (!pmu)
+                return -ENOMEM;
+
+        pmu->plat_device = pdev;
+
+        ret = pmu_parse_irqs(pmu);
+        if (ret)
+                goto out_free;
+
+        if (node && (of_id = of_match_node(of_table, pdev->dev.of_node))) {
+                init_fn = of_id->data;
+
+                pmu->secure_access = of_property_read_bool(pdev->dev.of_node,
+                                                           "secure-reg-access");
+
+                /* arm64 systems boot only as non-secure */
+                if (IS_ENABLED(CONFIG_ARM64) && pmu->secure_access) {
+                        pr_warn("ignoring \"secure-reg-access\" property for arm64\n");
+                        pmu->secure_access = false;
+                }
+
+                ret = init_fn(pmu);
+        } else if (probe_table) {
+                cpumask_setall(&pmu->supported_cpus);
+                ret = probe_current_pmu(pmu, probe_table);
+        }
+
+        if (ret) {
+                pr_info("%s: failed to probe PMU!\n", of_node_full_name(node));
+                goto out_free;
+        }
+
+        ret = armpmu_request_irqs(pmu);
+        if (ret)
+                goto out_free_irqs;
+
+        ret = armpmu_register(pmu);
+        if (ret)
+                goto out_free;
+
+        return 0;
+
+out_free_irqs:
+        armpmu_free_irqs(pmu);
+out_free:
+        pr_info("%s: failed to register PMU devices!\n",
+                of_node_full_name(node));
+        armpmu_free(pmu);
+        return ret;
+}
diff --git a/include/linux/perf/arm_pmu.h b/include/linux/perf/arm_pmu.h
index 4249914315a4..25556ebb1c7b 100644
--- a/include/linux/perf/arm_pmu.h
+++ b/include/linux/perf/arm_pmu.h
@@ -159,6 +159,13 @@ int arm_pmu_device_probe(struct platform_device *pdev,
                          const struct of_device_id *of_table,
                          const struct pmu_probe_info *probe_table);
 
+/* Internal functions only for core arm_pmu code */
+struct arm_pmu *armpmu_alloc(void);
+void armpmu_free(struct arm_pmu *pmu);
+int armpmu_register(struct arm_pmu *pmu);
+int armpmu_request_irqs(struct arm_pmu *armpmu);
+void armpmu_free_irqs(struct arm_pmu *armpmu);
+
 #define ARMV8_PMU_PDEV_NAME "armv8-pmu"
 
 #endif /* CONFIG_ARM_PMU */