root/arch/riscv/kernel/irq.c

DEFINITIONS

1. arch_show_interrupts
2. do_IRQ
3. init_IRQ

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2012 Regents of the University of California
   4  * Copyright (C) 2017 SiFive
   5  * Copyright (C) 2018 Christoph Hellwig
   6  */
   7 
   8 #include <linux/interrupt.h>
   9 #include <linux/irqchip.h>
  10 #include <linux/irqdomain.h>
  11 #include <linux/seq_file.h>
  12 #include <asm/smp.h>
  13 
  14 /*
  15  * Possible interrupt causes:
  16  */
  17 #define INTERRUPT_CAUSE_SOFTWARE        IRQ_S_SOFT
  18 #define INTERRUPT_CAUSE_TIMER           IRQ_S_TIMER
  19 #define INTERRUPT_CAUSE_EXTERNAL        IRQ_S_EXT
  20 
  21 int arch_show_interrupts(struct seq_file *p, int prec)
  22 {
  23         show_ipi_stats(p, prec);
  24         return 0;
  25 }
  26 
  27 asmlinkage __visible void __irq_entry do_IRQ(struct pt_regs *regs)
  28 {
  29         struct pt_regs *old_regs = set_irq_regs(regs);
  30 
  31         irq_enter();
  32         switch (regs->scause & ~SCAUSE_IRQ_FLAG) {
  33         case INTERRUPT_CAUSE_TIMER:
  34                 riscv_timer_interrupt();
  35                 break;
  36 #ifdef CONFIG_SMP
  37         case INTERRUPT_CAUSE_SOFTWARE:
  38                 /*
  39                  * We only use software interrupts to pass IPIs, so if a non-SMP
  40                  * system gets one, then we don't know what to do.
  41                  */
  42                 riscv_software_interrupt();
  43                 break;
  44 #endif
  45         case INTERRUPT_CAUSE_EXTERNAL:
  46                 handle_arch_irq(regs);
  47                 break;
  48         default:
  49                 pr_alert("unexpected interrupt cause 0x%lx", regs->scause);
  50                 BUG();
  51         }
  52         irq_exit();
  53 
  54         set_irq_regs(old_regs);
  55 }
  56 
  57 void __init init_IRQ(void)
  58 {
  59         irqchip_init();
  60 }