diff options
Diffstat (limited to 'arch/blackfin/kernel/irqchip.c')
| -rw-r--r-- | arch/blackfin/kernel/irqchip.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/arch/blackfin/kernel/irqchip.c b/arch/blackfin/kernel/irqchip.c new file mode 100644 index 00000000000..df5bf022cf7 --- /dev/null +++ b/arch/blackfin/kernel/irqchip.c @@ -0,0 +1,147 @@ +/* + * File: arch/blackfin/kernel/irqchip.c + * Based on: + * Author: + * + * 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 + */ + +#include <linux/kernel_stat.h> +#include <linux/module.h> +#include <linux/random.h> +#include <linux/seq_file.h> +#include <linux/kallsyms.h> +#include <linux/interrupt.h> +#include <linux/irq.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) +{ +} + +void ack_bad_irq(unsigned int irq) +{ + irq_err_count += 1; + 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, +}; + +int show_interrupts(struct seq_file *p, void *v) +{ + 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); + } + return 0; +} + +/* + * do_IRQ handles all hardware IRQ's. Decoded IRQs should not + * come via this function. Instead, they should provide their + * own 'handler' + */ + +#ifdef CONFIG_DO_IRQ_L1 +asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs)__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; + + old_regs = set_irq_regs(regs); + + /* + * Some hardware gives randomly wrong interrupts. Rather + * than crashing, do something sensible. + */ + if (irq >= NR_IRQS) + desc = &bad_irq_desc; + + irq_enter(); + + 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); +} + +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(); +} |