diff options
| -rw-r--r-- | arch/riscv/kernel/entry.S | 4 | ||||
| -rw-r--r-- | arch/riscv/kernel/irq.c | 52 |
2 files changed, 45 insertions, 11 deletions
diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S index 9aaf6c986771..fa2c08e3c05e 100644 --- a/arch/riscv/kernel/entry.S +++ b/arch/riscv/kernel/entry.S @@ -168,8 +168,8 @@ ENTRY(handle_exception) /* Handle interrupts */ move a0, sp /* pt_regs */ - REG_L a1, handle_arch_irq - jr a1 + move a1, s4 /* scause */ + tail do_IRQ 1: /* Exceptions run with interrupts enabled */ csrs sstatus, SR_SIE diff --git a/arch/riscv/kernel/irq.c b/arch/riscv/kernel/irq.c index 7bcdaed15703..ab5f3e22c7cc 100644 --- a/arch/riscv/kernel/irq.c +++ b/arch/riscv/kernel/irq.c @@ -1,21 +1,55 @@ +// 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> +/* + * 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) { +#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(); |