1/*
2 * Based on arch/arm/kernel/time.c
3 *
4 * Copyright (C) 1991, 1992, 1995  Linus Torvalds
5 * Modifications for ARM (C) 1994-2001 Russell King
6 * Copyright (C) 2012 ARM Ltd.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
19 */
20
21#include <linux/clockchips.h>
22#include <linux/export.h>
23#include <linux/kernel.h>
24#include <linux/interrupt.h>
25#include <linux/time.h>
26#include <linux/init.h>
27#include <linux/sched.h>
28#include <linux/smp.h>
29#include <linux/timex.h>
30#include <linux/errno.h>
31#include <linux/profile.h>
32#include <linux/syscore_ops.h>
33#include <linux/timer.h>
34#include <linux/irq.h>
35#include <linux/delay.h>
36#include <linux/clocksource.h>
37#include <linux/clk-provider.h>
38#include <linux/acpi.h>
39
40#include <clocksource/arm_arch_timer.h>
41
42#include <asm/thread_info.h>
43#include <asm/stacktrace.h>
44
45#ifdef CONFIG_SMP
46unsigned long profile_pc(struct pt_regs *regs)
47{
48	struct stackframe frame;
49
50	if (!in_lock_functions(regs->pc))
51		return regs->pc;
52
53	frame.fp = regs->regs[29];
54	frame.sp = regs->sp;
55	frame.pc = regs->pc;
56	do {
57		int ret = unwind_frame(&frame);
58		if (ret < 0)
59			return 0;
60	} while (in_lock_functions(frame.pc));
61
62	return frame.pc;
63}
64EXPORT_SYMBOL(profile_pc);
65#endif
66
67void __init time_init(void)
68{
69	u32 arch_timer_rate;
70
71	of_clk_init(NULL);
72	clocksource_of_init();
73
74	tick_setup_hrtimer_broadcast();
75
76	/*
77	 * Since ACPI or FDT will only one be available in the system,
78	 * we can use acpi_generic_timer_init() here safely
79	 */
80	acpi_generic_timer_init();
81
82	arch_timer_rate = arch_timer_get_rate();
83	if (!arch_timer_rate)
84		panic("Unable to initialise architected timer.\n");
85
86	/* Calibrate the delay loop directly */
87	lpj_fine = arch_timer_rate / HZ;
88}
89