blob: 3eee94f621ebd723195d326965cb6afc6998c85f [file] [log] [blame]
/*
* linux/arch/xtensa/kernel/irq.c
*
* Xtensa built-in interrupt controller and some generic functions copied
* from i386.
*
* Copyright (C) 2002 - 2013 Tensilica, Inc.
* Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
*
*
* Chris Zankel <chris@zankel.net>
* Kevin Chea
*
*/
#include <linux/module.h>
#include <linux/seq_file.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/kernel_stat.h>
#include <linux/irqchip.h>
#include <linux/irqchip/xtensa-mx.h>
#include <linux/irqchip/xtensa-pic.h>
#include <linux/irqdomain.h>
#include <linux/of.h>
#include <asm/mxregs.h>
#include <asm/uaccess.h>
#include <asm/platform.h>
atomic_t irq_err_count;
asmlinkage void do_IRQ(int hwirq, struct pt_regs *regs)
{
int irq = irq_find_mapping(NULL, hwirq);
if (hwirq >= NR_IRQS) {
printk(KERN_EMERG "%s: cannot handle IRQ %d\n",
__func__, hwirq);
}
#ifdef CONFIG_DEBUG_STACKOVERFLOW
/* Debugging check for stack overflow: is there less than 1KB free? */
{
unsigned long sp;
__asm__ __volatile__ ("mov %0, a1\n" : "=a" (sp));
sp &= THREAD_SIZE - 1;
if (unlikely(sp < (sizeof(thread_info) + 1024)))
printk("Stack overflow in do_IRQ: %ld\n",
sp - sizeof(struct thread_info));
}
#endif
generic_handle_irq(irq);
}
int arch_show_interrupts(struct seq_file *p, int prec)
{
#ifdef CONFIG_SMP
show_ipi_list(p, prec);
#endif
seq_printf(p, "%*s: ", prec, "ERR");
seq_printf(p, "%10u\n", atomic_read(&irq_err_count));
return 0;
}
int xtensa_irq_domain_xlate(const u32 *intspec, unsigned int intsize,
unsigned long int_irq, unsigned long ext_irq,
unsigned long *out_hwirq, unsigned int *out_type)
{
if (WARN_ON(intsize < 1 || intsize > 2))
return -EINVAL;
if (intsize == 2 && intspec[1] == 1) {
int_irq = xtensa_map_ext_irq(ext_irq);
if (int_irq < XCHAL_NUM_INTERRUPTS)
*out_hwirq = int_irq;
else
return -EINVAL;
} else {
*out_hwirq = int_irq;
}
*out_type = IRQ_TYPE_NONE;
return 0;
}
int xtensa_irq_map(struct irq_domain *d, unsigned int irq,
irq_hw_number_t hw)
{
struct irq_chip *irq_chip = d->host_data;
u32 mask = 1 << hw;
if (mask & XCHAL_INTTYPE_MASK_SOFTWARE) {
irq_set_chip_and_handler_name(irq, irq_chip,
handle_simple_irq, "level");
irq_set_status_flags(irq, IRQ_LEVEL);
} else if (mask & XCHAL_INTTYPE_MASK_EXTERN_EDGE) {
irq_set_chip_and_handler_name(irq, irq_chip,
handle_edge_irq, "edge");
irq_clear_status_flags(irq, IRQ_LEVEL);
} else if (mask & XCHAL_INTTYPE_MASK_EXTERN_LEVEL) {
irq_set_chip_and_handler_name(irq, irq_chip,
handle_level_irq, "level");
irq_set_status_flags(irq, IRQ_LEVEL);
} else if (mask & XCHAL_INTTYPE_MASK_TIMER) {
irq_set_chip_and_handler_name(irq, irq_chip,
handle_percpu_irq, "timer");
irq_clear_status_flags(irq, IRQ_LEVEL);
} else {/* XCHAL_INTTYPE_MASK_WRITE_ERROR */
/* XCHAL_INTTYPE_MASK_NMI */
irq_set_chip_and_handler_name(irq, irq_chip,
handle_level_irq, "level");
irq_set_status_flags(irq, IRQ_LEVEL);
}
return 0;
}
unsigned xtensa_map_ext_irq(unsigned ext_irq)
{
unsigned mask = XCHAL_INTTYPE_MASK_EXTERN_EDGE |
XCHAL_INTTYPE_MASK_EXTERN_LEVEL;
unsigned i;
for (i = 0; mask; ++i, mask >>= 1) {
if ((mask & 1) && ext_irq-- == 0)
return i;
}
return XCHAL_NUM_INTERRUPTS;
}
unsigned xtensa_get_ext_irq_no(unsigned irq)
{
unsigned mask = (XCHAL_INTTYPE_MASK_EXTERN_EDGE |
XCHAL_INTTYPE_MASK_EXTERN_LEVEL) &
((1u << irq) - 1);
return hweight32(mask);
}
void __init init_IRQ(void)
{
#ifdef CONFIG_OF
irqchip_init();
#else
#ifdef CONFIG_HAVE_SMP
xtensa_mx_init_legacy(NULL);
#else
xtensa_pic_init_legacy(NULL);
#endif
#endif
#ifdef CONFIG_SMP
ipi_init();
#endif
variant_init_irq();
}
#ifdef CONFIG_HOTPLUG_CPU
/*
* The 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.
*/
void migrate_irqs(void)
{
unsigned int i, cpu = smp_processor_id();
for_each_active_irq(i) {
struct irq_data *data = irq_get_irq_data(i);
unsigned int newcpu;
if (irqd_is_per_cpu(data))
continue;
if (!cpumask_test_cpu(cpu, data->affinity))
continue;
newcpu = cpumask_any_and(data->affinity, cpu_online_mask);
if (newcpu >= nr_cpu_ids) {
pr_info_ratelimited("IRQ%u no longer affine to CPU%u\n",
i, cpu);
cpumask_setall(data->affinity);
}
irq_set_affinity(i, data->affinity);
}
}
#endif /* CONFIG_HOTPLUG_CPU */