xref: /openbmc/linux/arch/riscv/kernel/time.c (revision 2022ca0a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012 Regents of the University of California
4  * Copyright (C) 2017 SiFive
5  */
6 
7 #include <linux/clocksource.h>
8 #include <linux/delay.h>
9 #include <asm/sbi.h>
10 
11 unsigned long riscv_timebase;
12 EXPORT_SYMBOL_GPL(riscv_timebase);
13 
14 void __init time_init(void)
15 {
16 	struct device_node *cpu;
17 	u32 prop;
18 
19 	cpu = of_find_node_by_path("/cpus");
20 	if (!cpu || of_property_read_u32(cpu, "timebase-frequency", &prop))
21 		panic(KERN_WARNING "RISC-V system with no 'timebase-frequency' in DTS\n");
22 	of_node_put(cpu);
23 	riscv_timebase = prop;
24 
25 	lpj_fine = riscv_timebase / HZ;
26 	timer_probe();
27 }
28