diff options
Diffstat (limited to 'arch/blackfin/kernel/irqchip.c')
| -rw-r--r-- | arch/blackfin/kernel/irqchip.c | 163 |
1 files changed, 70 insertions, 93 deletions
diff --git a/arch/blackfin/kernel/irqchip.c b/arch/blackfin/kernel/irqchip.c index 73647c15877..0ba25764b8c 100644 --- a/arch/blackfin/kernel/irqchip.c +++ b/arch/blackfin/kernel/irqchip.c @@ -1,30 +1,7 @@ /* - * File: arch/blackfin/kernel/irqchip.c - * Based on: - * Author: + * Copyright 2005-2009 Analog Devices Inc. * - * Created: - * Description: This file contains the simple DMA Implementation for Blackfin - * - * Modified: - * Copyright 2004-2006 Analog Devices Inc. - * - * Bugs: Enter bugs at http://blackfin.uclinux.org/ - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * 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 the file COPYING, or write - * to the Free Software Foundation, Inc., - * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * Licensed under the GPL-2 or later */ #include <linux/kernel_stat.h> @@ -34,100 +11,108 @@ #include <linux/kallsyms.h> #include <linux/interrupt.h> #include <linux/irq.h> +#include <linux/seq_file.h> +#include <asm/irq_handler.h> #include <asm/trace.h> +#include <asm/pda.h> -static unsigned long irq_err_count; -static spinlock_t irq_controller_lock; - -/* - * Dummy mask/unmask handler - */ -void dummy_mask_unmask_irq(unsigned int irq) -{ -} - +static atomic_t irq_err_count; void ack_bad_irq(unsigned int irq) { - irq_err_count += 1; + atomic_inc(&irq_err_count); printk(KERN_ERR "IRQ: spurious interrupt %d\n", irq); } -EXPORT_SYMBOL(ack_bad_irq); - -static struct irq_chip bad_chip = { - .ack = dummy_mask_unmask_irq, - .mask = dummy_mask_unmask_irq, - .unmask = dummy_mask_unmask_irq, -}; static struct irq_desc bad_irq_desc = { - .chip = &bad_chip, .handle_irq = handle_bad_irq, - .depth = 1, + .lock = __RAW_SPIN_LOCK_UNLOCKED(bad_irq_desc.lock), }; -int show_interrupts(struct seq_file *p, void *v) +#ifdef CONFIG_CPUMASK_OFFSTACK +/* We are not allocating a variable-sized bad_irq_desc.affinity */ +#error "Blackfin architecture does not support CONFIG_CPUMASK_OFFSTACK." +#endif + +#ifdef CONFIG_PROC_FS +int arch_show_interrupts(struct seq_file *p, int prec) { - int i = *(loff_t *) v; - struct irqaction *action; - unsigned long flags; - - if (i < NR_IRQS) { - spin_lock_irqsave(&irq_desc[i].lock, flags); - action = irq_desc[i].action; - if (!action) - goto unlock; - - seq_printf(p, "%3d: %10u ", i, kstat_irqs(i)); - seq_printf(p, " %s", action->name); - for (action = action->next; action; action = action->next) - seq_printf(p, ", %s", action->name); - - seq_putc(p, '\n'); - unlock: - spin_unlock_irqrestore(&irq_desc[i].lock, flags); - } else if (i == NR_IRQS) { - seq_printf(p, "Err: %10lu\n", irq_err_count); - } + int j; + + seq_printf(p, "%*s: ", prec, "NMI"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", cpu_pda[j].__nmi_count); + seq_printf(p, " CORE Non Maskable Interrupt\n"); + seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count)); return 0; } +#endif + +#ifdef CONFIG_DEBUG_STACKOVERFLOW +static void check_stack_overflow(int irq) +{ + /* Debugging check for stack overflow: is there less than STACK_WARN free? */ + long sp = __get_SP() & (THREAD_SIZE - 1); + + if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) { + dump_stack(); + pr_emerg("irq%i: possible stack overflow only %ld bytes free\n", + irq, sp - sizeof(struct thread_info)); + } +} +#else +static inline void check_stack_overflow(int irq) { } +#endif + +#ifndef CONFIG_IPIPE +static void maybe_lower_to_irq14(void) +{ + unsigned short pending, other_ints; + + /* + * If we're the only interrupt running (ignoring IRQ15 which + * is for syscalls), lower our priority to IRQ14 so that + * softirqs run at that level. If there's another, + * lower-level interrupt, irq_exit will defer softirqs to + * that. If the interrupt pipeline is enabled, we are already + * running at IRQ14 priority, so we don't need this code. + */ + CSYNC(); + pending = bfin_read_IPEND() & ~0x8000; + other_ints = pending & (pending - 1); + if (other_ints == 0) + lower_to_irq14(); +} +#else +static inline void maybe_lower_to_irq14(void) { } +#endif /* * do_IRQ handles all hardware IRQs. Decoded IRQs should not * come via this function. Instead, they should provide their * own 'handler' */ - #ifdef CONFIG_DO_IRQ_L1 __attribute__((l1_text)) #endif asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs) { - struct pt_regs *old_regs; - struct irq_desc *desc = irq_desc + irq; - unsigned short pending, other_ints; + struct pt_regs *old_regs = set_irq_regs(regs); + + irq_enter(); - old_regs = set_irq_regs(regs); + check_stack_overflow(irq); /* * Some hardware gives randomly wrong interrupts. Rather * than crashing, do something sensible. */ if (irq >= NR_IRQS) - desc = &bad_irq_desc; + handle_bad_irq(irq, &bad_irq_desc); + else + generic_handle_irq(irq); - irq_enter(); + maybe_lower_to_irq14(); - generic_handle_irq(irq); - - /* If we're the only interrupt running (ignoring IRQ15 which is for - syscalls), lower our priority to IRQ14 so that softirqs run at - that level. If there's another, lower-level interrupt, irq_exit - will defer softirqs to that. */ - CSYNC(); - pending = bfin_read_IPEND() & ~0x8000; - other_ints = pending & (pending - 1); - if (other_ints == 0) - lower_to_irq14(); irq_exit(); set_irq_regs(old_regs); @@ -135,14 +120,6 @@ asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs) void __init init_IRQ(void) { - struct irq_desc *desc; - int irq; - - spin_lock_init(&irq_controller_lock); - for (irq = 0, desc = irq_desc; irq < NR_IRQS; irq++, desc++) { - *desc = bad_irq_desc; - } - init_arch_irq(); #ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND |
