From 9fd85eb502a78bd812db58bd1f668b2a06ee30a5 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Fri, 6 Mar 2015 11:54:09 +0000 Subject: ARM: pmu: add support for interrupt-affinity property 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 Signed-off-by: Will Deacon --- arch/arm/kernel/perf_event_cpu.c | 69 ++++++++++++++++++++++++++++++++++++---- 1 file changed, 62 insertions(+), 7 deletions(-) (limited to 'arch/arm/kernel/perf_event_cpu.c') diff --git a/arch/arm/kernel/perf_event_cpu.c b/arch/arm/kernel/perf_event_cpu.c index 7eb86e294c68..91c7ba182dcd 100644 --- a/arch/arm/kernel/perf_event_cpu.c +++ b/arch/arm/kernel/perf_event_cpu.c @@ -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); } -- cgit v1.2.3-59-g8ed1b