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 #include <asm/processor.h> 11 12 unsigned long riscv_timebase; 13 EXPORT_SYMBOL_GPL(riscv_timebase); 14 15 void __init time_init(void) 16 { 17 struct device_node *cpu; 18 u32 prop; 19 20 cpu = of_find_node_by_path("/cpus"); 21 if (!cpu || of_property_read_u32(cpu, "timebase-frequency", &prop)) 22 panic(KERN_WARNING "RISC-V system with no 'timebase-frequency' in DTS\n"); 23 of_node_put(cpu); 24 riscv_timebase = prop; 25 26 lpj_fine = riscv_timebase / HZ; 27 timer_probe(); 28 } 29