2 * linux/arch/m68k/kernel/time.c
4 * Copyright (C) 1991, 1992, 1995 Linus Torvalds
6 * This file contains the m68k-specific time handling details.
7 * Most of the stuff is located in the machine specific files.
9 * 1997-09-10 Updated NTP code according to technical memorandum Jan '96
10 * "A Kernel Model for Precision Timekeeping" by Dave Mills
13 #include <linux/errno.h>
14 #include <linux/export.h>
15 #include <linux/module.h>
16 #include <linux/sched.h>
17 #include <linux/sched/loadavg.h>
18 #include <linux/kernel.h>
19 #include <linux/param.h>
20 #include <linux/string.h>
22 #include <linux/rtc.h>
23 #include <linux/platform_device.h>
25 #include <asm/machdep.h>
27 #include <asm/irq_regs.h>
29 #include <linux/time.h>
30 #include <linux/timex.h>
31 #include <linux/profile.h>
34 unsigned long (*mach_random_get_entropy
)(void);
35 EXPORT_SYMBOL_GPL(mach_random_get_entropy
);
39 * timer_interrupt() needs to keep up the real-time clock,
40 * as well as call the "xtime_update()" routine every clocktick
42 static irqreturn_t
timer_interrupt(int irq
, void *dummy
)
45 update_process_times(user_mode(get_irq_regs()));
46 profile_tick(CPU_PROFILING
);
48 #ifdef CONFIG_HEARTBEAT
49 /* use power LED as a heartbeat instead -- much more useful
50 for debugging -- based on the version for PReP by Cort */
51 /* acts like an actual heart beat -- ie thump-thump-pause... */
53 static unsigned cnt
= 0, period
= 0, dist
= 0;
55 if (cnt
== 0 || cnt
== dist
)
57 else if (cnt
== 7 || cnt
== dist
+7)
62 /* The hyperbolic function below modifies the heartbeat period
63 * length in dependency of the current (5min) load. It goes
64 * through the points f(0)=126, f(1)=86, f(5)=51,
66 period
= ((672<<FSHIFT
)/(5*avenrun
[0]+(7<<FSHIFT
))) + 30;
70 #endif /* CONFIG_HEARTBEAT */
74 #ifdef CONFIG_M68KCLASSIC
75 #if !IS_BUILTIN(CONFIG_RTC_DRV_GENERIC)
76 void read_persistent_clock64(struct timespec64
*ts
)
88 ts
->tv_sec
= mktime64(time
.tm_year
+ 1900, time
.tm_mon
+ 1, time
.tm_mday
,
89 time
.tm_hour
, time
.tm_min
, time
.tm_sec
);
93 #if IS_ENABLED(CONFIG_RTC_DRV_GENERIC)
94 static int rtc_generic_get_time(struct device
*dev
, struct rtc_time
*tm
)
100 static int rtc_generic_set_time(struct device
*dev
, struct rtc_time
*tm
)
102 if (mach_hwclk(1, tm
) < 0)
107 static int rtc_ioctl(struct device
*dev
, unsigned int cmd
, unsigned long arg
)
109 struct rtc_pll_info pll
;
110 struct rtc_pll_info __user
*argp
= (void __user
*)arg
;
114 if (!mach_get_rtc_pll
|| mach_get_rtc_pll(&pll
))
116 return copy_to_user(argp
, &pll
, sizeof pll
) ? -EFAULT
: 0;
119 if (!mach_set_rtc_pll
)
121 if (!capable(CAP_SYS_TIME
))
123 if (copy_from_user(&pll
, argp
, sizeof(pll
)))
125 return mach_set_rtc_pll(&pll
);
131 static const struct rtc_class_ops generic_rtc_ops
= {
133 .read_time
= rtc_generic_get_time
,
134 .set_time
= rtc_generic_set_time
,
137 static int __init
rtc_init(void)
139 struct platform_device
*pdev
;
144 pdev
= platform_device_register_data(NULL
, "rtc-generic", -1,
146 sizeof(generic_rtc_ops
));
147 return PTR_ERR_OR_ZERO(pdev
);
150 module_init(rtc_init
);
151 #endif /* CONFIG_RTC_DRV_GENERIC */
152 #endif /* CONFIG M68KCLASSIC */
154 void __init
time_init(void)
156 mach_sched_init(timer_interrupt
);