xref: /linux/arch/arm64/kernel/time.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
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/export.h>
22 #include <linux/kernel.h>
23 #include <linux/interrupt.h>
24 #include <linux/time.h>
25 #include <linux/init.h>
26 #include <linux/sched.h>
27 #include <linux/smp.h>
28 #include <linux/timex.h>
29 #include <linux/errno.h>
30 #include <linux/profile.h>
31 #include <linux/syscore_ops.h>
32 #include <linux/timer.h>
33 #include <linux/irq.h>
34 
35 #include <clocksource/arm_generic.h>
36 
37 #include <asm/thread_info.h>
38 #include <asm/stacktrace.h>
39 
40 #ifdef CONFIG_SMP
41 unsigned long profile_pc(struct pt_regs *regs)
42 {
43 	struct stackframe frame;
44 
45 	if (!in_lock_functions(regs->pc))
46 		return regs->pc;
47 
48 	frame.fp = regs->regs[29];
49 	frame.sp = regs->sp;
50 	frame.pc = regs->pc;
51 	do {
52 		int ret = unwind_frame(&frame);
53 		if (ret < 0)
54 			return 0;
55 	} while (in_lock_functions(frame.pc));
56 
57 	return frame.pc;
58 }
59 EXPORT_SYMBOL(profile_pc);
60 #endif
61 
62 void __init time_init(void)
63 {
64 	arm_generic_timer_init();
65 }
66