1 files changed, 236 insertions, 64 deletions

diff --git a/drivers/perf/arm_pmu_acpi.c b/drivers/perf/arm_pmu_acpi.c
index 0a9b78705ee8..e80f76d95e68 100644
--- a/drivers/perf/arm_pmu_acpi.c
+++ b/drivers/perf/arm_pmu_acpi.c
@@ -1,19 +1,19 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * ACPI probing code for ARM performance counters.
  *
  * Copyright (C) 2017 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.
  */
 
 #include <linux/acpi.h>
 #include <linux/cpumask.h>
 #include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/irqdesc.h>
 #include <linux/percpu.h>
 #include <linux/perf/arm_pmu.h>
 
+#include <asm/cpu.h>
 #include <asm/cputype.h>
 
 static DEFINE_PER_CPU(struct arm_pmu *, probed_pmus);
@@ -25,8 +25,6 @@ static int arm_pmu_acpi_register_irq(int cpu)
 	int gsi, trigger;
 
 	gicc = acpi_cpu_get_madt_gicc(cpu);
-	if (WARN_ON(!gicc))
-		return -EINVAL;
 
 	gsi = gicc->performance_interrupt;
 
@@ -65,13 +63,140 @@ static void arm_pmu_acpi_unregister_irq(int cpu)
 	int gsi;
 
 	gicc = acpi_cpu_get_madt_gicc(cpu);
-	if (!gicc)
-		return;
 
 	gsi = gicc->performance_interrupt;
-	acpi_unregister_gsi(gsi);
+	if (gsi)
+		acpi_unregister_gsi(gsi);
+}
+
+static int __maybe_unused
+arm_acpi_register_pmu_device(struct platform_device *pdev, u8 len,
+			     u16 (*parse_gsi)(struct acpi_madt_generic_interrupt *))
+{
+	int cpu, this_hetid, hetid, irq, ret;
+	u16 this_gsi = 0, gsi = 0;
+
+	/*
+	 * Ensure that platform device must have IORESOURCE_IRQ
+	 * resource to hold gsi interrupt.
+	 */
+	if (pdev->num_resources != 1)
+		return -ENXIO;
+
+	if (pdev->resource[0].flags != IORESOURCE_IRQ)
+		return -ENXIO;
+
+	/*
+	 * Sanity check all the GICC tables for the same interrupt
+	 * number. For now, only support homogeneous ACPI machines.
+	 */
+	for_each_possible_cpu(cpu) {
+		struct acpi_madt_generic_interrupt *gicc;
+
+		gicc = acpi_cpu_get_madt_gicc(cpu);
+		if (gicc->header.length < len)
+			return gsi ? -ENXIO : 0;
+
+		this_gsi = parse_gsi(gicc);
+		this_hetid = find_acpi_cpu_topology_hetero_id(cpu);
+		if (!gsi) {
+			hetid = this_hetid;
+			gsi = this_gsi;
+		} else if (hetid != this_hetid || gsi != this_gsi) {
+			pr_warn("ACPI: %s: must be homogeneous\n", pdev->name);
+			return -ENXIO;
+		}
+	}
+
+	if (!this_gsi)
+		return 0;
+
+	irq = acpi_register_gsi(NULL, gsi, ACPI_LEVEL_SENSITIVE, ACPI_ACTIVE_HIGH);
+	if (irq < 0) {
+		pr_warn("ACPI: %s Unable to register interrupt: %d\n", pdev->name, gsi);
+		return -ENXIO;
+	}
+
+	pdev->resource[0].start = irq;
+	ret = platform_device_register(pdev);
+	if (ret)
+		acpi_unregister_gsi(gsi);
+
+	return ret;
 }
 
+#if IS_ENABLED(CONFIG_ARM_SPE_PMU)
+static struct resource spe_resources[] = {
+	{
+		/* irq */
+		.flags          = IORESOURCE_IRQ,
+	}
+};
+
+static struct platform_device spe_dev = {
+	.name = ARMV8_SPE_PDEV_NAME,
+	.id = -1,
+	.resource = spe_resources,
+	.num_resources = ARRAY_SIZE(spe_resources)
+};
+
+static u16 arm_spe_parse_gsi(struct acpi_madt_generic_interrupt *gicc)
+{
+	return gicc->spe_interrupt;
+}
+
+/*
+ * For lack of a better place, hook the normal PMU MADT walk
+ * and create a SPE device if we detect a recent MADT with
+ * a homogeneous PPI mapping.
+ */
+static void arm_spe_acpi_register_device(void)
+{
+	int ret = arm_acpi_register_pmu_device(&spe_dev, ACPI_MADT_GICC_SPE,
+					       arm_spe_parse_gsi);
+	if (ret)
+		pr_warn("ACPI: SPE: Unable to register device\n");
+}
+#else
+static inline void arm_spe_acpi_register_device(void)
+{
+}
+#endif /* CONFIG_ARM_SPE_PMU */
+
+#if IS_ENABLED(CONFIG_CORESIGHT_TRBE)
+static struct resource trbe_resources[] = {
+	{
+		/* irq */
+		.flags          = IORESOURCE_IRQ,
+	}
+};
+
+static struct platform_device trbe_dev = {
+	.name = ARMV8_TRBE_PDEV_NAME,
+	.id = -1,
+	.resource = trbe_resources,
+	.num_resources = ARRAY_SIZE(trbe_resources)
+};
+
+static u16 arm_trbe_parse_gsi(struct acpi_madt_generic_interrupt *gicc)
+{
+	return gicc->trbe_interrupt;
+}
+
+static void arm_trbe_acpi_register_device(void)
+{
+	int ret = arm_acpi_register_pmu_device(&trbe_dev, ACPI_MADT_GICC_TRBE,
+					       arm_trbe_parse_gsi);
+	if (ret)
+		pr_warn("ACPI: TRBE: Unable to register device\n");
+}
+#else
+static inline void arm_trbe_acpi_register_device(void)
+{
+
+}
+#endif /* CONFIG_CORESIGHT_TRBE */
+
 static int arm_pmu_acpi_parse_irqs(void)
 {
 	int irq, cpu, irq_cpu, err;
@@ -87,7 +212,15 @@ static int arm_pmu_acpi_parse_irqs(void)
 			pr_warn("No ACPI PMU IRQ for CPU%d\n", cpu);
 		}
 
+		/*
+		 * Log and request the IRQ so the core arm_pmu code can manage
+		 * it. We'll have to sanity-check IRQs later when we associate
+		 * them with their PMUs.
+		 */
 		per_cpu(pmu_irqs, cpu) = irq;
+		err = armpmu_request_irq(&probed_pmus, irq, cpu);
+		if (err)
+			goto out_err;
 	}
 
 	return 0;
@@ -113,7 +246,7 @@ out_err:
 	return err;
 }
 
-static struct arm_pmu *arm_pmu_acpi_find_alloc_pmu(void)
+static struct arm_pmu *arm_pmu_acpi_find_pmu(void)
 {
 	unsigned long cpuid = read_cpuid_id();
 	struct arm_pmu *pmu;
@@ -127,16 +260,52 @@ static struct arm_pmu *arm_pmu_acpi_find_alloc_pmu(void)
 		return pmu;
 	}
 
-	pmu = armpmu_alloc();
-	if (!pmu) {
-		pr_warn("Unable to allocate PMU for CPU%d\n",
-			smp_processor_id());
-		return NULL;
+	return NULL;
+}
+
+/*
+ * Check whether the new IRQ is compatible with those already associated with
+ * the PMU (e.g. we don't have mismatched PPIs).
+ */
+static bool pmu_irq_matches(struct arm_pmu *pmu, int irq)
+{
+	struct pmu_hw_events __percpu *hw_events = pmu->hw_events;
+	int cpu;
+
+	if (!irq)
+		return true;
+
+	for_each_cpu(cpu, &pmu->supported_cpus) {
+		int other_irq = per_cpu(hw_events->irq, cpu);
+		if (!other_irq)
+			continue;
+
+		if (irq == other_irq)
+			continue;
+		if (!irq_is_percpu_devid(irq) && !irq_is_percpu_devid(other_irq))
+			continue;
+
+		pr_warn("mismatched PPIs detected\n");
+		return false;
 	}
 
-	pmu->acpi_cpuid = cpuid;
+	return true;
+}
 
-	return pmu;
+static void arm_pmu_acpi_associate_pmu_cpu(struct arm_pmu *pmu,
+					   unsigned int cpu)
+{
+	int irq = per_cpu(pmu_irqs, cpu);
+
+	per_cpu(probed_pmus, cpu) = pmu;
+
+	if (pmu_irq_matches(pmu, irq)) {
+		struct pmu_hw_events __percpu *hw_events;
+		hw_events = pmu->hw_events;
+		per_cpu(hw_events->irq, cpu) = irq;
+	}
+
+	cpumask_set_cpu(cpu, &pmu->supported_cpus);
 }
 
 /*
@@ -151,50 +320,50 @@ static struct arm_pmu *arm_pmu_acpi_find_alloc_pmu(void)
 static int arm_pmu_acpi_cpu_starting(unsigned int cpu)
 {
 	struct arm_pmu *pmu;
-	struct pmu_hw_events __percpu *hw_events;
-	int irq;
 
 	/* If we've already probed this CPU, we have nothing to do */
 	if (per_cpu(probed_pmus, cpu))
 		return 0;
 
-	irq = per_cpu(pmu_irqs, cpu);
-
-	pmu = arm_pmu_acpi_find_alloc_pmu();
-	if (!pmu)
-		return -ENOMEM;
+	pmu = arm_pmu_acpi_find_pmu();
+	if (!pmu) {
+		pr_warn_ratelimited("Unable to associate CPU%d with a PMU\n",
+				    cpu);
+		return 0;
+	}
 
-	cpumask_set_cpu(cpu, &pmu->supported_cpus);
+	arm_pmu_acpi_associate_pmu_cpu(pmu, cpu);
+	return 0;
+}
 
-	per_cpu(probed_pmus, cpu) = pmu;
+static void arm_pmu_acpi_probe_matching_cpus(struct arm_pmu *pmu,
+					     unsigned long cpuid)
+{
+	int cpu;
 
-	/*
-	 * Log and request the IRQ so the core arm_pmu code can manage it.  In
-	 * some situations (e.g. mismatched PPIs), we may fail to request the
-	 * IRQ. However, it may be too late for us to do anything about it.
-	 * The common ARM PMU code will log a warning in this case.
-	 */
-	hw_events = pmu->hw_events;
-	per_cpu(hw_events->irq, cpu) = irq;
-	armpmu_request_irq(pmu, cpu);
+	for_each_online_cpu(cpu) {
+		unsigned long cpu_cpuid = per_cpu(cpu_data, cpu).reg_midr;
 
-	/*
-	 * Ideally, we'd probe the PMU here when we find the first matching
-	 * CPU. We can't do that for several reasons; see the comment in
-	 * arm_pmu_acpi_init().
-	 *
-	 * So for the time being, we're done.
-	 */
-	return 0;
+		if (cpu_cpuid == cpuid)
+			arm_pmu_acpi_associate_pmu_cpu(pmu, cpu);
+	}
 }
 
 int arm_pmu_acpi_probe(armpmu_init_fn init_fn)
 {
 	int pmu_idx = 0;
-	int cpu, ret;
+	unsigned int cpu;
+	int ret;
 
-	if (acpi_disabled)
-		return 0;
+	ret = arm_pmu_acpi_parse_irqs();
+	if (ret)
+		return ret;
+
+	ret = cpuhp_setup_state_nocalls(CPUHP_AP_PERF_ARM_ACPI_STARTING,
+					"perf/arm/pmu_acpi:starting",
+					arm_pmu_acpi_cpu_starting, NULL);
+	if (ret)
+		return ret;
 
 	/*
 	 * Initialise and register the set of PMUs which we know about right
@@ -209,13 +378,27 @@ int arm_pmu_acpi_probe(armpmu_init_fn init_fn)
 	 * For the moment, as with the platform/DT case, we need at least one
 	 * of a PMU's CPUs to be online at probe time.
 	 */
-	for_each_possible_cpu(cpu) {
+	for_each_online_cpu(cpu) {
 		struct arm_pmu *pmu = per_cpu(probed_pmus, cpu);
+		unsigned long cpuid;
 		char *base_name;
 
-		if (!pmu || pmu->name)
+		/* If we've already probed this CPU, we have nothing to do */
+		if (pmu)
 			continue;
 
+		pmu = armpmu_alloc();
+		if (!pmu) {
+			pr_warn("Unable to allocate PMU for CPU%d\n",
+				cpu);
+			return -ENOMEM;
+		}
+
+		cpuid = per_cpu(cpu_data, cpu).reg_midr;
+		pmu->acpi_cpuid = cpuid;
+
+		arm_pmu_acpi_probe_matching_cpus(pmu, cpuid);
+
 		ret = init_fn(pmu);
 		if (ret == -ENODEV) {
 			/* PMU not handled by this driver, or not present */
@@ -235,33 +418,22 @@ int arm_pmu_acpi_probe(armpmu_init_fn init_fn)
 		ret = armpmu_register(pmu);
 		if (ret) {
 			pr_warn("Failed to register PMU for CPU%d\n", cpu);
+			kfree(pmu->name);
 			return ret;
 		}
 	}
 
-	return 0;
+	return ret;
 }
 
 static int arm_pmu_acpi_init(void)
 {
-	int ret;
-
 	if (acpi_disabled)
 		return 0;
 
-	/*
-	 * We can't request IRQs yet, since we don't know the cookie value
-	 * until we know which CPUs share the same logical PMU. We'll handle
-	 * that in arm_pmu_acpi_cpu_starting().
-	 */
-	ret = arm_pmu_acpi_parse_irqs();
-	if (ret)
-		return ret;
-
-	ret = cpuhp_setup_state(CPUHP_AP_PERF_ARM_ACPI_STARTING,
-				"perf/arm/pmu_acpi:starting",
-				arm_pmu_acpi_cpu_starting, NULL);
+	arm_spe_acpi_register_device();
+	arm_trbe_acpi_register_device();
 
-	return ret;
+	return 0;
 }
 subsys_initcall(arm_pmu_acpi_init)