lkml.org 
[lkml]   [2016]   [Apr]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4/4] arm64: pmu: add A72 cpu type, support multiple PMU types
Date
ARM big/little machines can have PMU's with differing PMU counters.
ACPI systems should be able to support this as well. Also add support
for A72 PMU counters.

Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
---
arch/arm64/include/asm/cputype.h | 1 +
arch/arm64/kernel/perf_event.c | 1 +
drivers/perf/arm_pmu.c | 54 +++++++--
drivers/perf/arm_pmu_acpi.c | 229 +++++++++++++++++++++++++++------------
4 files changed, 204 insertions(+), 81 deletions(-)

diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h
index 87e1985..1e40799 100644
--- a/arch/arm64/include/asm/cputype.h
+++ b/arch/arm64/include/asm/cputype.h
@@ -74,6 +74,7 @@

#define ARM_CPU_PART_AEM_V8 0xD0F
#define ARM_CPU_PART_FOUNDATION 0xD00
+#define ARM_CPU_PART_CORTEX_A72 0xD08
#define ARM_CPU_PART_CORTEX_A57 0xD07
#define ARM_CPU_PART_CORTEX_A53 0xD03

diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c
index 8f12eac..1893f77 100644
--- a/arch/arm64/kernel/perf_event.c
+++ b/arch/arm64/kernel/perf_event.c
@@ -870,6 +870,7 @@ static const struct of_device_id armv8_pmu_of_device_ids[] = {
static const struct pmu_probe_info armv8_pmu_probe_table[] = {
ARMV8_PMU_PART_PROBE(ARM_CPU_PART_CORTEX_A53, armv8_a53_pmu_init),
ARMV8_PMU_PART_PROBE(ARM_CPU_PART_CORTEX_A57, armv8_a57_pmu_init),
+ ARMV8_PMU_PART_PROBE(ARM_CPU_PART_CORTEX_A72, armv8_a72_pmu_init),
PMU_PROBE(0, 0, armv8_pmuv3_init), /* if all else fails... */
{ /* sentinel value */ }
};
diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
index 49fa845..ffca517 100644
--- a/drivers/perf/arm_pmu.c
+++ b/drivers/perf/arm_pmu.c
@@ -11,6 +11,7 @@
*/
#define pr_fmt(fmt) "hw perfevents: " fmt

+#include <linux/acpi.h>
#include <linux/bitmap.h>
#include <linux/cpumask.h>
#include <linux/cpu_pm.h>
@@ -24,6 +25,7 @@
#include <linux/irq.h>
#include <linux/irqdesc.h>

+#include <asm/cpu.h>
#include <asm/cputype.h>
#include <asm/irq_regs.h>

@@ -853,25 +855,51 @@ static void cpu_pmu_destroy(struct arm_pmu *cpu_pmu)
}

/*
- * CPU PMU identification and probing.
+ * CPU PMU identification and probing. Its possible to have
+ * multiple CPU types in an ARM machine. Assure that we are
+ * picking the right PMU types based on the CPU in question
*/
-static int probe_current_pmu(struct arm_pmu *pmu,
- const struct pmu_probe_info *info)
+static int probe_plat_pmu(struct arm_pmu *pmu,
+ const struct pmu_probe_info *info,
+ unsigned int pmuid)
{
- int cpu = get_cpu();
- unsigned int cpuid = read_cpuid_id();
int ret = -ENODEV;
+ int cpu;
+ int aff_ctr = 0;
+ struct platform_device *pdev = pmu->plat_device;
+ int irq = platform_get_irq(pdev, 0);

- pr_info("probing PMU on CPU %d\n", cpu);
+ if (irq >= 0 && !irq_is_percpu(irq)) {
+ pmu->irq_affinity = kcalloc(pdev->num_resources, sizeof(int),
+ GFP_KERNEL);
+ if (!pmu->irq_affinity)
+ return -ENOMEM;
+ }

+ for_each_possible_cpu(cpu) {
+ struct cpuinfo_arm64 *cinfo = per_cpu_ptr(&cpu_data, cpu);
+ unsigned int cpuid = cinfo->reg_midr;
+
+ if (cpuid == pmuid) {
+ cpumask_set_cpu(cpu, &pmu->supported_cpus);
+ pr_devel("enable pmu on cpu %d\n", cpu);
+ if (pmu->irq_affinity) {
+ pmu->irq_affinity[aff_ctr] = cpu;
+ aff_ctr++;
+ }
+ }
+ }
+
+ pr_debug("probing PMU %X\n", pmuid);
+ /* find the type of PMU given the CPU */
for (; info->init != NULL; info++) {
- if ((cpuid & info->mask) != info->cpuid)
+ if ((pmuid & info->mask) != info->cpuid)
continue;
+ pr_devel("Found PMU\n");
ret = info->init(pmu);
break;
}

- put_cpu();
return ret;
}

@@ -997,8 +1025,14 @@ int arm_pmu_device_probe(struct platform_device *pdev,
if (!ret)
ret = init_fn(pmu);
} else {
- cpumask_setall(&pmu->supported_cpus);
- ret = probe_current_pmu(pmu, probe_table);
+ if (acpi_disabled) {
+ /* use the boot cpu. */
+ struct cpuinfo_arm64 *cinfo = per_cpu_ptr(&cpu_data, 0);
+ unsigned int cpuid = cinfo->reg_midr;
+
+ ret = probe_plat_pmu(pmu, probe_table, cpuid);
+ } else
+ ret = probe_plat_pmu(pmu, probe_table, pdev->id);
}

if (ret) {
diff --git a/drivers/perf/arm_pmu_acpi.c b/drivers/perf/arm_pmu_acpi.c
index 722f4ca..793092c 100644
--- a/drivers/perf/arm_pmu_acpi.c
+++ b/drivers/perf/arm_pmu_acpi.c
@@ -2,6 +2,7 @@
* PMU support
*
* Copyright (C) 2015 Red Hat Inc.
+ * Copyright (C) 2016 ARM Ltd.
* Author: Mark Salter <msalter@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
@@ -9,21 +10,35 @@
*
*/

+#define pr_fmt(fmt) "ACPI-PMU: " fmt
#include <linux/perf/arm_pmu.h>
#include <linux/platform_device.h>
#include <linux/acpi.h>
#include <linux/irq.h>
#include <linux/irqdesc.h>

+#include <asm/cpu.h>
+
#define PMU_PDEV_NAME "armv8-pmu"

struct pmu_irq {
- int gsi;
- int trigger;
+ int gsi;
+ int trigger;
+ bool registered;
+};
+
+struct pmu_types {
+ int cpu_type;
+ int cpu_count;
};

static struct pmu_irq pmu_irqs[NR_CPUS] __initdata;

+/*
+ * called from acpi_map_gic_cpu_interface()'s MADT parsing callback during boot
+ * this routine saves off the GSI's and their trigger state for use when we are
+ * ready to build the PMU platform device.
+*/
void __init arm_pmu_parse_acpi(int cpu, struct acpi_madt_generic_interrupt *gic)
{
pmu_irqs[cpu].gsi = gic->performance_interrupt;
@@ -31,95 +46,167 @@ void __init arm_pmu_parse_acpi(int cpu, struct acpi_madt_generic_interrupt *gic)
pmu_irqs[cpu].trigger = ACPI_EDGE_SENSITIVE;
else
pmu_irqs[cpu].trigger = ACPI_LEVEL_SENSITIVE;
+ pr_info("Assign CPU %d girq %d level %d\n", cpu, pmu_irqs[cpu].gsi,
+ pmu_irqs[cpu].trigger);
}

-#ifndef CONFIG_SMP
-/*
- * In !SMP case, we parse for boot CPU IRQ here.
- */
-static int __init acpi_parse_pmu_irqs(struct acpi_subtable_header *header,
- const unsigned long end)
-{
- struct acpi_madt_generic_interrupt *gic;
-
- gic = (struct acpi_madt_generic_interrupt *)header;
-
- if (cpu_logical_map(0) == (gic->arm_mpidr & MPIDR_HWID_BITMASK))
- arm_pmu_parse_acpi(0, gic);
-
- return 0;
-}
-
-static void __init acpi_parse_boot_cpu(void)
+/* count number and type of CPU's in system */
+static void __init arm_pmu_acpi_determine_cpu_types(struct pmu_types *pmus)
{
- count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
- acpi_parse_pmu_irqs, 0);
+ int i, j;
+
+ for_each_possible_cpu(i) {
+ struct cpuinfo_arm64 *cinfo = per_cpu_ptr(&cpu_data, i);
+
+ pr_devel("Present CPU %d is a %X\n", i,
+ MIDR_PARTNUM(cinfo->reg_midr));
+ for (j = 0; j < NR_CPUS; j++) {
+ if (pmus[j].cpu_type == MIDR_PARTNUM(cinfo->reg_midr)) {
+ pmus[j].cpu_count++;
+ break;
+ }
+ if (pmus[j].cpu_count == 0) {
+ pmus[j].cpu_type = MIDR_PARTNUM(cinfo->reg_midr);
+ pmus[j].cpu_count++;
+ break;
+ }
+ }
+ }
}
-#else
-#define acpi_parse_boot_cpu() do {} while (0)
-#endif

-static int __init pmu_acpi_init(void)
+static int __init arm_pmu_acpi_register_pmu(int count, struct resource *res,
+ int last_cpu_id)
{
- struct platform_device *pdev;
- struct pmu_irq *pirq = pmu_irqs;
- struct resource *res, *r;
+ int i;
int err = -ENOMEM;
- int i, count, irq;
+ bool free_gsi = false;
+ struct platform_device *pdev;

- if (acpi_disabled)
- return 0;
+ if (count) {
+ pdev = platform_device_alloc(PMU_PDEV_NAME, last_cpu_id);
+
+ if (pdev) {
+ err = platform_device_add_resources(pdev,
+ res, count);
+ if (!err) {
+ err = platform_device_add(pdev);
+ if (err) {
+ pr_warn("Unable to register PMU device\n");
+ free_gsi = true;
+ }
+ } else {
+ pr_warn("Unable to add resources to device\n");
+ free_gsi = true;
+ platform_device_put(pdev);
+ }
+ } else {
+ pr_warn("Unable to allocate platform device\n");
+ free_gsi = true;
+ }
+ }

- acpi_parse_boot_cpu();
+ /* unmark (and possibly unregister) registered GSIs */
+ for_each_possible_cpu(i) {
+ if (pmu_irqs[i].registered) {
+ if (free_gsi)
+ acpi_unregister_gsi(pmu_irqs[i].gsi);
+ pmu_irqs[i].registered = false;
+ }
+ }

- /* Must have irq for boot boot cpu, at least */
- if (pirq->gsi == 0)
- return -EINVAL;
+ return err;
+}

- irq = acpi_register_gsi(NULL, pirq->gsi, pirq->trigger,
- ACPI_ACTIVE_HIGH);
+/*
+ * For the given cpu/pmu type, walk all known GSIs, register them, and add
+ * them to the resource structure. Return the number of GSI's contained
+ * in the res structure, and the id of the last CPU/PMU we added.
+ */
+static int __init arm_pmu_acpi_gsi_res(struct pmu_types *pmus,
+ struct resource *res, int *last_cpu_id)
+{
+ int i, count;
+ int irq;
+
+ pr_info("Setting up %d PMUs for CPU type %X\n", pmus->cpu_count,
+ pmus->cpu_type);
+ /* lets group all the PMU's from similar CPU's together */
+ count = 0;
+ for_each_possible_cpu(i) {
+ struct cpuinfo_arm64 *cinfo = per_cpu_ptr(&cpu_data, i);
+
+ if (pmus->cpu_type == MIDR_PARTNUM(cinfo->reg_midr)) {
+ pr_devel("Setting up CPU %d\n", i);
+ if (pmu_irqs[i].gsi == 0)
+ continue;
+
+ irq = acpi_register_gsi(NULL, pmu_irqs[i].gsi,
+ pmu_irqs[i].trigger,
+ ACPI_ACTIVE_HIGH);

- if (irq_is_percpu(irq))
- count = 1;
- else
- for (i = 1, count = 1; i < NR_CPUS; i++)
- if (pmu_irqs[i].gsi)
- ++count;
+ res[count].start = res[count].end = irq;
+ res[count].flags = IORESOURCE_IRQ;

- pdev = platform_device_alloc(PMU_PDEV_NAME, -1);
- if (!pdev)
- goto err_free_gsi;
+ if (pmu_irqs[i].trigger == ACPI_EDGE_SENSITIVE)
+ res[count].flags |= IORESOURCE_IRQ_HIGHEDGE;
+ else
+ res[count].flags |= IORESOURCE_IRQ_HIGHLEVEL;

- res = kcalloc(count, sizeof(*res), GFP_KERNEL);
- if (!res)
- goto err_free_device;
+ pmu_irqs[i].registered = true;
+ count++;
+ (*last_cpu_id) = cinfo->reg_midr;

- for (i = 0, r = res; i < count; i++, pirq++, r++) {
- if (i)
- irq = acpi_register_gsi(NULL, pirq->gsi, pirq->trigger,
- ACPI_ACTIVE_HIGH);
- r->start = r->end = irq;
- r->flags = IORESOURCE_IRQ;
- if (pirq->trigger == ACPI_EDGE_SENSITIVE)
- r->flags |= IORESOURCE_IRQ_HIGHEDGE;
- else
- r->flags |= IORESOURCE_IRQ_HIGHLEVEL;
+ if (irq_is_percpu(irq))
+ pr_debug("PPI detected\n");
+ }
}
+ return count;
+}

- err = platform_device_add_resources(pdev, res, count);
- if (!err)
- err = platform_device_add(pdev);
- kfree(res);
- if (!err)
- return 0;
+static int __init pmu_acpi_init(void)
+{
+ struct resource *res;
+ int err = -ENOMEM;
+ int count;
+ int j, last_cpu_id;
+ struct pmu_types *pmus;

-err_free_device:
- platform_device_put(pdev);
+ pr_debug("Prepare registration\n");
+ if (acpi_disabled)
+ return 0;

-err_free_gsi:
- for (i = 0; i < count; i++)
- acpi_unregister_gsi(pmu_irqs[i].gsi);
+ pmus = kcalloc(NR_CPUS, sizeof(struct pmu_types), GFP_KERNEL);
+
+ if (pmus) {
+ arm_pmu_acpi_determine_cpu_types(pmus);
+
+ for (j = 0; pmus[j].cpu_count; j++) {
+ pr_devel("CPU type %d, count %d\n", pmus[j].cpu_type,
+ pmus[j].cpu_count);
+ res = kcalloc(pmus[j].cpu_count,
+ sizeof(struct resource), GFP_KERNEL);
+
+ /* for a given PMU type collect all the GSIs. */
+ if (res) {
+ count = arm_pmu_acpi_gsi_res(&pmus[j], res,
+ &last_cpu_id);
+ /*
+ * register this set of interrupts
+ * with a new PMU device
+ */
+ err = arm_pmu_acpi_register_pmu(count,
+ res,
+ last_cpu_id);
+ kfree(res);
+ } else
+ pr_warn("PMU unable to allocate interrupt resource space\n");
+ }
+
+ kfree(pmus);
+ } else
+ pr_warn("PMU: Unable to allocate pmu count structures\n");

return err;
}
+
arch_initcall(pmu_acpi_init);
--
2.4.3
\
 
 \ /
  Last update: 2016-04-09 00:21    [W:0.066 / U:0.044 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site