| /* |
| * Based on arch/arm/kernel/irq.c |
| * |
| * Copyright (C) 1992 Linus Torvalds |
| * Modifications for ARM processor Copyright (C) 1995-2000 Russell King. |
| * Support for Dynamic Tick Timer Copyright (C) 2004-2005 Nokia Corporation. |
| * Dynamic Tick Timer written by Tony Lindgren <tony@atomide.com> and |
| * Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>. |
| * Copyright (C) 2012 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. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #include <linux/kernel_stat.h> |
| #include <linux/irq.h> |
| #include <linux/smp.h> |
| #include <linux/init.h> |
| #include <linux/irqchip.h> |
| #include <linux/seq_file.h> |
| #include <linux/ratelimit.h> |
| |
| unsigned long irq_err_count; |
| |
| int arch_show_interrupts(struct seq_file *p, int prec) |
| { |
| #ifdef CONFIG_SMP |
| show_ipi_list(p, prec); |
| #endif |
| seq_printf(p, "%*s: %10lu\n", prec, "Err", irq_err_count); |
| return 0; |
| } |
| |
| /* |
| * handle_IRQ handles all hardware IRQ's. Decoded IRQs should |
| * not come via this function. Instead, they should provide their |
| * own 'handler'. Used by platform code implementing C-based 1st |
| * level decoding. |
| */ |
| void handle_IRQ(unsigned int irq, struct pt_regs *regs) |
| { |
| struct pt_regs *old_regs = set_irq_regs(regs); |
| |
| irq_enter(); |
| |
| /* |
| * Some hardware gives randomly wrong interrupts. Rather |
| * than crashing, do something sensible. |
| */ |
| if (unlikely(irq >= nr_irqs)) { |
| pr_warn_ratelimited("Bad IRQ%u\n", irq); |
| ack_bad_irq(irq); |
| } else { |
| generic_handle_irq(irq); |
| } |
| |
| irq_exit(); |
| set_irq_regs(old_regs); |
| } |
| |
| void __init set_handle_irq(void (*handle_irq)(struct pt_regs *)) |
| { |
| if (handle_arch_irq) |
| return; |
| |
| handle_arch_irq = handle_irq; |
| } |
| |
| void __init init_IRQ(void) |
| { |
| irqchip_init(); |
| if (!handle_arch_irq) |
| panic("No interrupt controller found."); |
| } |
| |
| #ifdef CONFIG_HOTPLUG_CPU |
| static bool migrate_one_irq(struct irq_desc *desc) |
| { |
| struct irq_data *d = irq_desc_get_irq_data(desc); |
| const struct cpumask *affinity = d->affinity; |
| |
| /* |
| * If this is a per-CPU interrupt, or the affinity does not |
| * include this CPU, then we have nothing to do. |
| */ |
| if (irqd_is_per_cpu(d) || !cpumask_test_cpu(smp_processor_id(), affinity)) |
| return false; |
| |
| if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) |
| affinity = cpu_online_mask; |
| return irq_set_affinity_locked(d, affinity, 0) == 0; |
| } |
| |
| /* |
| * The current CPU has been marked offline. Migrate IRQs off this CPU. |
| * If the affinity settings do not allow other CPUs, force them onto any |
| * available CPU. |
| * |
| * Note: we must iterate over all IRQs, whether they have an attached |
| * action structure or not, as we need to get chained interrupts too. |
| */ |
| void migrate_irqs(void) |
| { |
| unsigned int i; |
| struct irq_desc *desc; |
| unsigned long flags; |
| |
| local_irq_save(flags); |
| |
| for_each_irq_desc(i, desc) { |
| bool affinity_broken; |
| |
| raw_spin_lock(&desc->lock); |
| affinity_broken = migrate_one_irq(desc); |
| raw_spin_unlock(&desc->lock); |
| |
| if (affinity_broken) |
| pr_warn_ratelimited("IRQ%u no longer affine to CPU%u\n", |
| i, smp_processor_id()); |
| } |
| |
| local_irq_restore(flags); |
| } |
| #endif /* CONFIG_HOTPLUG_CPU */ |