diff options
Diffstat (limited to 'arch/mn10300/kernel/irq.c')
| -rw-r--r-- | arch/mn10300/kernel/irq.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/arch/mn10300/kernel/irq.c b/arch/mn10300/kernel/irq.c new file mode 100644 index 000000000000..761c434a2488 --- /dev/null +++ b/arch/mn10300/kernel/irq.c @@ -0,0 +1,235 @@ +/* MN10300 Arch-specific interrupt handling + * + * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/kernel_stat.h> +#include <linux/seq_file.h> +#include <asm/setup.h> + +unsigned long __mn10300_irq_enabled_epsw = EPSW_IE | EPSW_IM_7; +EXPORT_SYMBOL(__mn10300_irq_enabled_epsw); + +atomic_t irq_err_count; + +/* + * MN10300 INTC controller operations + */ +static void mn10300_cpupic_disable(unsigned int irq) +{ + u16 tmp = GxICR(irq); + GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_DETECT; + tmp = GxICR(irq); +} + +static void mn10300_cpupic_enable(unsigned int irq) +{ + u16 tmp = GxICR(irq); + GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_ENABLE; + tmp = GxICR(irq); +} + +static void mn10300_cpupic_ack(unsigned int irq) +{ + u16 tmp; + *(volatile u8 *) &GxICR(irq) = GxICR_DETECT; + tmp = GxICR(irq); +} + +static void mn10300_cpupic_mask(unsigned int irq) +{ + u16 tmp = GxICR(irq); + GxICR(irq) = (tmp & GxICR_LEVEL); + tmp = GxICR(irq); +} + +static void mn10300_cpupic_mask_ack(unsigned int irq) +{ + u16 tmp = GxICR(irq); + GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_DETECT; + tmp = GxICR(irq); +} + +static void mn10300_cpupic_unmask(unsigned int irq) +{ + u16 tmp = GxICR(irq); + GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_ENABLE | GxICR_DETECT; + tmp = GxICR(irq); +} + +static void mn10300_cpupic_end(unsigned int irq) +{ + u16 tmp = GxICR(irq); + GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_ENABLE; + tmp = GxICR(irq); +} + +static struct irq_chip mn10300_cpu_pic = { + .name = "cpu", + .disable = mn10300_cpupic_disable, + .enable = mn10300_cpupic_enable, + .ack = mn10300_cpupic_ack, + .mask = mn10300_cpupic_mask, + .mask_ack = mn10300_cpupic_mask_ack, + .unmask = mn10300_cpupic_unmask, + .end = mn10300_cpupic_end, +}; + +/* + * 'what should we do if we get a hw irq event on an illegal vector'. + * each architecture has to answer this themselves. + */ +void ack_bad_irq(int irq) +{ + printk(KERN_WARNING "unexpected IRQ trap at vector %02x\n", irq); +} + +/* + * change the level at which an IRQ executes + * - must not be called whilst interrupts are being processed! + */ +void set_intr_level(int irq, u16 level) +{ + u16 tmp; + + if (in_interrupt()) + BUG(); + + tmp = GxICR(irq); + GxICR(irq) = (tmp & GxICR_ENABLE) | level; + tmp = GxICR(irq); +} + +/* + * mark an interrupt to be ACK'd after interrupt handlers have been run rather + * than before + * - see Documentation/mn10300/features.txt + */ +void set_intr_postackable(int irq) +{ + set_irq_handler(irq, handle_level_irq); +} + +/* + * initialise the interrupt system + */ +void __init init_IRQ(void) +{ + int irq; + + for (irq = 0; irq < NR_IRQS; irq++) + if (irq_desc[irq].chip == &no_irq_type) + set_irq_chip_and_handler(irq, &mn10300_cpu_pic, + handle_edge_irq); + unit_init_IRQ(); +} + +/* + * handle normal device IRQs + */ +asmlinkage void do_IRQ(void) +{ + unsigned long sp, epsw, irq_disabled_epsw, old_irq_enabled_epsw; + int irq; + + sp = current_stack_pointer(); + if (sp - (sp & ~(THREAD_SIZE - 1)) < STACK_WARN) + BUG(); + + /* make sure local_irq_enable() doesn't muck up the interrupt priority + * setting in EPSW */ + old_irq_enabled_epsw = __mn10300_irq_enabled_epsw; + local_save_flags(epsw); + __mn10300_irq_enabled_epsw = EPSW_IE | (EPSW_IM & epsw); + irq_disabled_epsw = EPSW_IE | MN10300_CLI_LEVEL; + + __IRQ_STAT(smp_processor_id(), __irq_count)++; + + irq_enter(); + + for (;;) { + /* ask the interrupt controller for the next IRQ to process + * - the result we get depends on EPSW.IM + */ + irq = IAGR & IAGR_GN; + if (!irq) + break; + + local_irq_restore(irq_disabled_epsw); + + generic_handle_irq(irq >> 2); + + /* restore IRQ controls for IAGR access */ + local_irq_restore(epsw); + } + + __mn10300_irq_enabled_epsw = old_irq_enabled_epsw; + + irq_exit(); +} + +/* + * Display interrupt management information through /proc/interrupts + */ +int show_interrupts(struct seq_file *p, void *v) +{ + int i = *(loff_t *) v, j, cpu; + struct irqaction *action; + unsigned long flags; + + switch (i) { + /* display column title bar naming CPUs */ + case 0: + seq_printf(p, " "); + for (j = 0; j < NR_CPUS; j++) + if (cpu_online(j)) + seq_printf(p, "CPU%d ", j); + seq_putc(p, '\n'); + break; + + /* display information rows, one per active CPU */ + case 1 ... NR_IRQS - 1: + spin_lock_irqsave(&irq_desc[i].lock, flags); + + action = irq_desc[i].action; + if (action) { + seq_printf(p, "%3d: ", i); + for_each_present_cpu(cpu) + seq_printf(p, "%10u ", kstat_cpu(cpu).irqs[i]); + seq_printf(p, " %14s.%u", irq_desc[i].chip->name, + (GxICR(i) & GxICR_LEVEL) >> + GxICR_LEVEL_SHIFT); + seq_printf(p, " %s", action->name); + + for (action = action->next; + action; + action = action->next) + seq_printf(p, ", %s", action->name); + + seq_putc(p, '\n'); + } + + spin_unlock_irqrestore(&irq_desc[i].lock, flags); + break; + + /* polish off with NMI and error counters */ + case NR_IRQS: + seq_printf(p, "NMI: "); + for (j = 0; j < NR_CPUS; j++) + if (cpu_online(j)) + seq_printf(p, "%10u ", nmi_count(j)); + seq_putc(p, '\n'); + + seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count)); + break; + } + + return 0; +} |