From 71efb063f4a145ae420be054f5a91dcf7c19b375 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Fri, 18 Feb 2011 16:21:06 +0100 Subject: ARM: 6742/1: pmu: avoid setting IRQ affinity on UP systems Now that we can execute a CONFIG_SMP kernel on a uniprocessor system, extra care has to be taken in the PMU IRQ affinity setting code to ensure that we don't always fail to initialise. This patch changes the CPU PMU initialisation code so that when we only have a single IRQ, whose affinity can not be changed at the controller, we report success (0) rather than -EINVAL. Reported-by: Avik Sil Acked-by: Jamie Iles Signed-off-by: Will Deacon Signed-off-by: Russell King --- arch/arm/kernel/pmu.c | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/arch/arm/kernel/pmu.c b/arch/arm/kernel/pmu.c index b8af96ea62e6..2c79eec19262 100644 --- a/arch/arm/kernel/pmu.c +++ b/arch/arm/kernel/pmu.c @@ -97,28 +97,34 @@ set_irq_affinity(int irq, irq, cpu); return err; #else - return 0; + return -EINVAL; #endif } static int init_cpu_pmu(void) { - int i, err = 0; + int i, irqs, err = 0; struct platform_device *pdev = pmu_devices[ARM_PMU_DEVICE_CPU]; - if (!pdev) { - err = -ENODEV; - goto out; - } + if (!pdev) + return -ENODEV; + + irqs = pdev->num_resources; + + /* + * If we have a single PMU interrupt that we can't shift, assume that + * we're running on a uniprocessor machine and continue. + */ + if (irqs == 1 && !irq_can_set_affinity(platform_get_irq(pdev, 0))) + return 0; - for (i = 0; i < pdev->num_resources; ++i) { + for (i = 0; i < irqs; ++i) { err = set_irq_affinity(platform_get_irq(pdev, i), i); if (err) break; } -out: return err; } -- cgit v1.2.2