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/acpi.h>
8#include <linux/of_clk.h>
9#include <linux/clockchips.h>
10#include <linux/clocksource.h>
11#include <linux/delay.h>
12#include <asm/sbi.h>
13#include <asm/processor.h>
14#include <asm/timex.h>
15#include <asm/paravirt.h>
16
17unsigned long riscv_timebase __ro_after_init;
18EXPORT_SYMBOL_GPL(riscv_timebase);
19
20void __init time_init(void)
21{
22	struct device_node *cpu;
23	struct acpi_table_rhct *rhct;
24	acpi_status status;
25	u32 prop;
26
27	if (acpi_disabled) {
28		cpu = of_find_node_by_path("/cpus");
29		if (!cpu || of_property_read_u32(cpu, "timebase-frequency", &prop))
30			panic("RISC-V system with no 'timebase-frequency' in DTS\n");
31
32		of_node_put(cpu);
33		riscv_timebase = prop;
34		of_clk_init(NULL);
35	} else {
36		status = acpi_get_table(ACPI_SIG_RHCT, 0, (struct acpi_table_header **)&rhct);
37		if (ACPI_FAILURE(status))
38			panic("RISC-V ACPI system with no RHCT table\n");
39
40		riscv_timebase = rhct->time_base_freq;
41		acpi_put_table((struct acpi_table_header *)rhct);
42	}
43
44	lpj_fine = riscv_timebase / HZ;
45
46	timer_probe();
47
48	tick_setup_hrtimer_broadcast();
49
50	pv_time_init();
51}
52