Loading...
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/arch/arm/kernel/time.c
4 *
5 * Copyright (C) 1991, 1992, 1995 Linus Torvalds
6 * Modifications for ARM (C) 1994-2001 Russell King
7 *
8 * This file contains the ARM-specific time handling details:
9 * reading the RTC at bootup, etc...
10 */
11#include <linux/clockchips.h>
12#include <linux/clocksource.h>
13#include <linux/errno.h>
14#include <linux/export.h>
15#include <linux/init.h>
16#include <linux/interrupt.h>
17#include <linux/irq.h>
18#include <linux/kernel.h>
19#include <linux/of_clk.h>
20#include <linux/profile.h>
21#include <linux/sched.h>
22#include <linux/sched_clock.h>
23#include <linux/smp.h>
24#include <linux/time.h>
25#include <linux/timex.h>
26#include <linux/timer.h>
27
28#include <asm/mach/arch.h>
29#include <asm/mach/time.h>
30#include <asm/stacktrace.h>
31#include <asm/thread_info.h>
32
33#if defined(CONFIG_RTC_DRV_CMOS) || defined(CONFIG_RTC_DRV_CMOS_MODULE) || \
34 defined(CONFIG_NVRAM) || defined(CONFIG_NVRAM_MODULE)
35/* this needs a better home */
36DEFINE_SPINLOCK(rtc_lock);
37EXPORT_SYMBOL(rtc_lock);
38#endif /* pc-style 'CMOS' RTC support */
39
40/* change this if you have some constant time drift */
41#define USECS_PER_JIFFY (1000000/HZ)
42
43#ifdef CONFIG_SMP
44unsigned long profile_pc(struct pt_regs *regs)
45{
46 struct stackframe frame;
47
48 if (!in_lock_functions(regs->ARM_pc))
49 return regs->ARM_pc;
50
51 arm_get_current_stackframe(regs, &frame);
52 do {
53 int ret = unwind_frame(&frame);
54 if (ret < 0)
55 return 0;
56 } while (in_lock_functions(frame.pc));
57
58 return frame.pc;
59}
60EXPORT_SYMBOL(profile_pc);
61#endif
62
63static void dummy_clock_access(struct timespec64 *ts)
64{
65 ts->tv_sec = 0;
66 ts->tv_nsec = 0;
67}
68
69static clock_access_fn __read_persistent_clock = dummy_clock_access;
70
71void read_persistent_clock64(struct timespec64 *ts)
72{
73 __read_persistent_clock(ts);
74}
75
76int __init register_persistent_clock(clock_access_fn read_persistent)
77{
78 /* Only allow the clockaccess functions to be registered once */
79 if (__read_persistent_clock == dummy_clock_access) {
80 if (read_persistent)
81 __read_persistent_clock = read_persistent;
82 return 0;
83 }
84
85 return -EINVAL;
86}
87
88void __init time_init(void)
89{
90 if (machine_desc->init_time) {
91 machine_desc->init_time();
92 } else {
93#ifdef CONFIG_COMMON_CLK
94 of_clk_init(NULL);
95#endif
96 timer_probe();
97 tick_setup_hrtimer_broadcast();
98 }
99}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/arch/arm/kernel/time.c
4 *
5 * Copyright (C) 1991, 1992, 1995 Linus Torvalds
6 * Modifications for ARM (C) 1994-2001 Russell King
7 *
8 * This file contains the ARM-specific time handling details:
9 * reading the RTC at bootup, etc...
10 */
11#include <linux/clk-provider.h>
12#include <linux/clocksource.h>
13#include <linux/errno.h>
14#include <linux/export.h>
15#include <linux/init.h>
16#include <linux/interrupt.h>
17#include <linux/irq.h>
18#include <linux/kernel.h>
19#include <linux/profile.h>
20#include <linux/sched.h>
21#include <linux/sched_clock.h>
22#include <linux/smp.h>
23#include <linux/time.h>
24#include <linux/timex.h>
25#include <linux/timer.h>
26
27#include <asm/mach/arch.h>
28#include <asm/mach/time.h>
29#include <asm/stacktrace.h>
30#include <asm/thread_info.h>
31
32#if defined(CONFIG_RTC_DRV_CMOS) || defined(CONFIG_RTC_DRV_CMOS_MODULE) || \
33 defined(CONFIG_NVRAM) || defined(CONFIG_NVRAM_MODULE)
34/* this needs a better home */
35DEFINE_SPINLOCK(rtc_lock);
36EXPORT_SYMBOL(rtc_lock);
37#endif /* pc-style 'CMOS' RTC support */
38
39/* change this if you have some constant time drift */
40#define USECS_PER_JIFFY (1000000/HZ)
41
42#ifdef CONFIG_SMP
43unsigned long profile_pc(struct pt_regs *regs)
44{
45 struct stackframe frame;
46
47 if (!in_lock_functions(regs->ARM_pc))
48 return regs->ARM_pc;
49
50 arm_get_current_stackframe(regs, &frame);
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}
59EXPORT_SYMBOL(profile_pc);
60#endif
61
62#ifndef CONFIG_GENERIC_CLOCKEVENTS
63/*
64 * Kernel system timer support.
65 */
66void timer_tick(void)
67{
68 profile_tick(CPU_PROFILING);
69 xtime_update(1);
70#ifndef CONFIG_SMP
71 update_process_times(user_mode(get_irq_regs()));
72#endif
73}
74#endif
75
76static void dummy_clock_access(struct timespec64 *ts)
77{
78 ts->tv_sec = 0;
79 ts->tv_nsec = 0;
80}
81
82static clock_access_fn __read_persistent_clock = dummy_clock_access;
83
84void read_persistent_clock64(struct timespec64 *ts)
85{
86 __read_persistent_clock(ts);
87}
88
89int __init register_persistent_clock(clock_access_fn read_persistent)
90{
91 /* Only allow the clockaccess functions to be registered once */
92 if (__read_persistent_clock == dummy_clock_access) {
93 if (read_persistent)
94 __read_persistent_clock = read_persistent;
95 return 0;
96 }
97
98 return -EINVAL;
99}
100
101void __init time_init(void)
102{
103 if (machine_desc->init_time) {
104 machine_desc->init_time();
105 } else {
106#ifdef CONFIG_COMMON_CLK
107 of_clk_init(NULL);
108#endif
109 timer_probe();
110 }
111}