diff options
Diffstat (limited to 'arch/riscv/kernel/irq.c')
| -rw-r--r-- | arch/riscv/kernel/irq.c | 55 |
1 files changed, 44 insertions, 11 deletions
diff --git a/arch/riscv/kernel/irq.c b/arch/riscv/kernel/irq.c index b74cbfbce2d0..0cfac48a1272 100644 --- a/arch/riscv/kernel/irq.c +++ b/arch/riscv/kernel/irq.c @@ -1,24 +1,57 @@ +// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2012 Regents of the University of California * Copyright (C) 2017 SiFive - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation, version 2. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. + * Copyright (C) 2018 Christoph Hellwig */ #include <linux/interrupt.h> #include <linux/irqchip.h> #include <linux/irqdomain.h> -#ifdef CONFIG_RISCV_INTC -#include <linux/irqchip/irq-riscv-intc.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) { |