LXR linux/arch/mips/include/asm/irq.h

   1/*
   2 * This file is subject to the terms and conditions of the GNU General Public
   3 * License.  See the file "COPYING" in the main directory of this archive
   4 * for more details.
   5 *
   6 * Copyright (C) 1994 by Waldorf GMBH, written by Ralf Baechle
   7 * Copyright (C) 1995, 96, 97, 98, 99, 2000, 01, 02, 03 by Ralf Baechle
   8 */
   9#ifndef _ASM_IRQ_H
  10#define _ASM_IRQ_H
  11
  12#include <linux/linkage.h>
  13#include <linux/smp.h>
  14#include <linux/irqdomain.h>
  15
  16#include <asm/mipsmtregs.h>
  17
  18#include <irq.h>
  19
  20#define IRQ_STACK_SIZE                  THREAD_SIZE
  21#define IRQ_STACK_START                 (IRQ_STACK_SIZE - 16)
  22
  23extern void *irq_stack[NR_CPUS];
  24
  25/*
  26 * The highest address on the IRQ stack contains a dummy frame put down in
  27 * genex.S (handle_int & except_vec_vi_handler) which is structured as follows:
  28 *
  29 *   top ------------
  30 *       | task sp  | <- irq_stack[cpu] + IRQ_STACK_START
  31 *       ------------
  32 *       |          | <- First frame of IRQ context
  33 *       ------------
  34 *
  35 * task sp holds a copy of the task stack pointer where the struct pt_regs
  36 * from exception entry can be found.
  37 */
  38
  39static inline bool on_irq_stack(int cpu, unsigned long sp)
  40{
  41        unsigned long low = (unsigned long)irq_stack[cpu];
  42        unsigned long high = low + IRQ_STACK_SIZE;
  43
  44        return (low <= sp && sp <= high);
  45}
  46
  47#ifdef CONFIG_I8259
  48static inline int irq_canonicalize(int irq)
  49{
  50        return ((irq == I8259A_IRQ_BASE + 2) ? I8259A_IRQ_BASE + 9 : irq);
  51}
  52#else
  53#define irq_canonicalize(irq) (irq)     /* Sane hardware, sane code ... */
  54#endif
  55
  56asmlinkage void plat_irq_dispatch(void);
  57
  58extern void do_IRQ(unsigned int irq);
  59
  60extern void arch_init_irq(void);
  61extern void spurious_interrupt(void);
  62
  63extern int allocate_irqno(void);
  64extern void alloc_legacy_irqno(void);
  65extern void free_irqno(unsigned int irq);
  66
  67/*
  68 * Before R2 the timer and performance counter interrupts were both fixed to
  69 * IE7.  Since R2 their number has to be read from the c0_intctl register.
  70 */
  71#define CP0_LEGACY_COMPARE_IRQ 7
  72#define CP0_LEGACY_PERFCNT_IRQ 7
  73
  74extern int cp0_compare_irq;
  75extern int cp0_compare_irq_shift;
  76extern int cp0_perfcount_irq;
  77extern int cp0_fdc_irq;
  78
  79extern int get_c0_fdc_int(void);
  80
  81void arch_trigger_cpumask_backtrace(const struct cpumask *mask,
  82                                    bool exclude_self);
  83#define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace
  84
  85#endif /* _ASM_IRQ_H */
  86