Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-26 22:21:42 +00:00
Code Issues Packages Projects Releases Wiki Activity

ARM: pmu: add support for interrupt-affinity property

Browse Source 
Historically, the PMU devicetree bindings have expected SPIs to be
listed in order of *logical* CPU number. This is problematic for
bootloaders, especially when the boot CPU (logical ID 0) isn't listed
first in the devicetree.

This patch adds a new optional property, interrupt-affinity, to the
PMU node which allows the interrupt affinity to be described using
a list of phandled to CPU nodes, with each entry in the list
corresponding to the SPI at the same index in the interrupts property.

Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Will Deacon 2015-03-06 11:54:09 +00:00
parent e429817b40
commit 9fd85eb502
2 changed files with 63 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
arch/arm/include/asm/pmu.h
View File

@ -92,6 +92,7 @@ struct pmu_hw_events {
struct arm_pmu {
struct pmu pmu;
cpumask_t active_irqs;
int *irq_affinity;
char *name;
irqreturn_t (*handle_irq)(int irq_num, void *dev);
void (*enable)(struct perf_event *event);

69
arch/arm/kernel/perf_event_cpu.c
View File

@ -92,11 +92,16 @@ static void cpu_pmu_free_irq(struct arm_pmu *cpu_pmu)
free_percpu_irq(irq, &hw_events->percpu_pmu);
} else {
for (i = 0; i < irqs; ++i) {
if (!cpumask_test_and_clear_cpu(i, &cpu_pmu->active_irqs))
int cpu = i;
if (cpu_pmu->irq_affinity)
cpu = cpu_pmu->irq_affinity[i];
if (!cpumask_test_and_clear_cpu(cpu, &cpu_pmu->active_irqs))
continue;
irq = platform_get_irq(pmu_device, i);
if (irq >= 0)
free_irq(irq, per_cpu_ptr(&hw_events->percpu_pmu, i));
free_irq(irq, per_cpu_ptr(&hw_events->percpu_pmu, cpu));
}
}
}
@ -128,32 +133,37 @@ static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler)
on_each_cpu(cpu_pmu_enable_percpu_irq, &irq, 1);
} else {
for (i = 0; i < irqs; ++i) {
int cpu = i;
err = 0;
irq = platform_get_irq(pmu_device, i);
if (irq < 0)
continue;
if (cpu_pmu->irq_affinity)
cpu = cpu_pmu->irq_affinity[i];
/*
* If we have a single PMU interrupt that we can't shift,
* assume that we're running on a uniprocessor machine and
* continue. Otherwise, continue without this interrupt.
*/
if (irq_set_affinity(irq, cpumask_of(i)) && irqs > 1) {
if (irq_set_affinity(irq, cpumask_of(cpu)) && irqs > 1) {
pr_warn("unable to set irq affinity (irq=%d, cpu=%u)\n",
irq, i);
irq, cpu);
continue;
}
err = request_irq(irq, handler,
IRQF_NOBALANCING | IRQF_NO_THREAD, "arm-pmu",
per_cpu_ptr(&hw_events->percpu_pmu, i));
per_cpu_ptr(&hw_events->percpu_pmu, cpu));
if (err) {
pr_err("unable to request IRQ%d for ARM PMU counters\n",
irq);
return err;
}
cpumask_set_cpu(i, &cpu_pmu->active_irqs);
cpumask_set_cpu(cpu, &cpu_pmu->active_irqs);
}
}
@ -291,6 +301,48 @@ static int probe_current_pmu(struct arm_pmu *pmu)
return ret;
}
static int of_pmu_irq_cfg(struct platform_device *pdev)
{
int i;
int *irqs = kcalloc(pdev->num_resources, sizeof(*irqs), GFP_KERNEL);
if (!irqs)
return -ENOMEM;
for (i = 0; i < pdev->num_resources; ++i) {
struct device_node *dn;
int cpu;
dn = of_parse_phandle(pdev->dev.of_node, "interrupt-affinity",
i);
if (!dn) {
pr_warn("Failed to parse %s/interrupt-affinity[%d]\n",
of_node_full_name(dn), i);
break;
}
for_each_possible_cpu(cpu)
if (arch_find_n_match_cpu_physical_id(dn, cpu, NULL))
break;
of_node_put(dn);
if (cpu >= nr_cpu_ids) {
pr_warn("Failed to find logical CPU for %s\n",
dn->name);
break;
}
irqs[i] = cpu;
}
if (i == pdev->num_resources)
cpu_pmu->irq_affinity = irqs;
else
kfree(irqs);
return 0;
}
static int cpu_pmu_device_probe(struct platform_device *pdev)
{
const struct of_device_id *of_id;
@ -315,7 +367,10 @@ static int cpu_pmu_device_probe(struct platform_device *pdev)
if (node && (of_id = of_match_node(cpu_pmu_of_device_ids, pdev->dev.of_node))) {
init_fn = of_id->data;
ret = init_fn(pmu);
ret = of_pmu_irq_cfg(pdev);
if (!ret)
ret = init_fn(pmu);
} else {
ret = probe_current_pmu(pmu);
}