ubuntu-linux-kernel/arch/riscv/kernel/time.c

62 lines
1.5 KiB
C

/*
* 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.
*/
#include <linux/clocksource.h>
#include <linux/clockchips.h>
#include <linux/delay.h>
#ifdef CONFIG_RISCV_TIMER
#include <linux/timer_riscv.h>
#endif
#include <asm/sbi.h>
unsigned long riscv_timebase;
DECLARE_PER_CPU(struct clock_event_device, riscv_clock_event);
void riscv_timer_interrupt(void)
{
#ifdef CONFIG_RISCV_TIMER
/*
* FIXME: This needs to be cleaned up along with the rest of the IRQ
* handling cleanup. See irq.c for more details.
*/
struct clock_event_device *evdev = this_cpu_ptr(&riscv_clock_event);
evdev->event_handler(evdev);
#endif
}
void __init init_clockevent(void)
{
timer_probe();
csr_set(sie, SIE_STIE);
}
void __init time_init(void)
{
struct device_node *cpu;
u32 prop;
cpu = of_find_node_by_path("/cpus");
if (!cpu || of_property_read_u32(cpu, "timebase-frequency", &prop))
panic(KERN_WARNING "RISC-V system with no 'timebase-frequency' in DTS\n");
riscv_timebase = prop;
lpj_fine = riscv_timebase / HZ;
init_clockevent();
}