// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2012 Regents of the University of California * Copyright (C) 2017 SiFive * Copyright (C) 2018 Christoph Hellwig */ #include <linux/interrupt.h> #include <linux/irqchip.h> #include <linux/irqdomain.h> /* * Possible interrupt causes: */ #define INTERRUPT_CAUSE_SOFTWARE 1 #define INTERRUPT_CAUSE_TIMER 5 #define INTERRUPT_CAUSE_EXTERNAL 9 /* * The high order bit of the trap cause register is always set for * interrupts, which allows us to differentiate them from exceptions * quickly. The INTERRUPT_CAUSE_* macros don't contain that bit, so we * need to mask it off. */ #define INTERRUPT_CAUSE_FLAG (1UL << (__riscv_xlen - 1)) asmlinkage void __irq_entry do_IRQ(struct pt_regs *regs, unsigned long cause) { struct pt_regs *old_regs = set_irq_regs(regs); irq_enter(); switch (cause & ~INTERRUPT_CAUSE_FLAG) { case INTERRUPT_CAUSE_TIMER: riscv_timer_interrupt(); break; #ifdef CONFIG_SMP case INTERRUPT_CAUSE_SOFTWARE: /* * We only use software interrupts to pass IPIs, so if a non-SMP * system gets one, then we don't know what to do. */ riscv_software_interrupt(); break; #endif case INTERRUPT_CAUSE_EXTERNAL: handle_arch_irq(regs); break; default: panic("unexpected interrupt cause"); } irq_exit(); set_irq_regs(old_regs); } void __init init_IRQ(void) { irqchip_init(); }