linux_old1/arch/riscv/kernel/time.c

35 lines
1009 B
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/delay.h>
#include <asm/sbi.h>
unsigned long riscv_timebase;
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");
of_node_put(cpu);
riscv_timebase = prop;
lpj_fine = riscv_timebase / HZ;
timer_probe();
}