1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * linux/arch/m68k/kernel/time.c |
4 | * |
5 | * Copyright (C) 1991, 1992, 1995 Linus Torvalds |
6 | * |
7 | * This file contains the m68k-specific time handling details. |
8 | * Most of the stuff is located in the machine specific files. |
9 | * |
10 | * 1997-09-10 Updated NTP code according to technical memorandum Jan '96 |
11 | * "A Kernel Model for Precision Timekeeping" by Dave Mills |
12 | */ |
13 | |
14 | #include <linux/errno.h> |
15 | #include <linux/export.h> |
16 | #include <linux/module.h> |
17 | #include <linux/sched.h> |
18 | #include <linux/sched/loadavg.h> |
19 | #include <linux/kernel.h> |
20 | #include <linux/param.h> |
21 | #include <linux/string.h> |
22 | #include <linux/mm.h> |
23 | #include <linux/rtc.h> |
24 | #include <linux/platform_device.h> |
25 | |
26 | #include <asm/machdep.h> |
27 | #include <asm/io.h> |
28 | #include <asm/irq_regs.h> |
29 | |
30 | #include <linux/time.h> |
31 | #include <linux/timex.h> |
32 | #include <linux/profile.h> |
33 | |
34 | |
35 | unsigned long (*mach_random_get_entropy)(void); |
36 | EXPORT_SYMBOL_GPL(mach_random_get_entropy); |
37 | |
38 | #ifdef CONFIG_HEARTBEAT |
39 | void timer_heartbeat(void) |
40 | { |
41 | /* use power LED as a heartbeat instead -- much more useful |
42 | for debugging -- based on the version for PReP by Cort */ |
43 | /* acts like an actual heart beat -- ie thump-thump-pause... */ |
44 | if (mach_heartbeat) { |
45 | static unsigned cnt = 0, period = 0, dist = 0; |
46 | |
47 | if (cnt == 0 || cnt == dist) |
48 | mach_heartbeat( 1 ); |
49 | else if (cnt == 7 || cnt == dist+7) |
50 | mach_heartbeat( 0 ); |
51 | |
52 | if (++cnt > period) { |
53 | cnt = 0; |
54 | /* The hyperbolic function below modifies the heartbeat period |
55 | * length in dependency of the current (5min) load. It goes |
56 | * through the points f(0)=126, f(1)=86, f(5)=51, |
57 | * f(inf)->30. */ |
58 | period = ((672<<FSHIFT)/(5*avenrun[0]+(7<<FSHIFT))) + 30; |
59 | dist = period / 4; |
60 | } |
61 | } |
62 | } |
63 | #endif /* CONFIG_HEARTBEAT */ |
64 | |
65 | #ifdef CONFIG_M68KCLASSIC |
66 | /* machine dependent timer functions */ |
67 | int (*mach_hwclk) (int, struct rtc_time*); |
68 | EXPORT_SYMBOL(mach_hwclk); |
69 | |
70 | int (*mach_get_rtc_pll)(struct rtc_pll_info *); |
71 | int (*mach_set_rtc_pll)(struct rtc_pll_info *); |
72 | EXPORT_SYMBOL(mach_get_rtc_pll); |
73 | EXPORT_SYMBOL(mach_set_rtc_pll); |
74 | |
75 | #if !IS_BUILTIN(CONFIG_RTC_DRV_GENERIC) |
76 | void read_persistent_clock64(struct timespec64 *ts) |
77 | { |
78 | struct rtc_time time; |
79 | |
80 | ts->tv_sec = 0; |
81 | ts->tv_nsec = 0; |
82 | |
83 | if (!mach_hwclk) |
84 | return; |
85 | |
86 | mach_hwclk(0, &time); |
87 | |
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); |
90 | } |
91 | #endif |
92 | |
93 | #if IS_ENABLED(CONFIG_RTC_DRV_GENERIC) |
94 | static int rtc_generic_get_time(struct device *dev, struct rtc_time *tm) |
95 | { |
96 | mach_hwclk(0, tm); |
97 | return 0; |
98 | } |
99 | |
100 | static int rtc_generic_set_time(struct device *dev, struct rtc_time *tm) |
101 | { |
102 | if (mach_hwclk(1, tm) < 0) |
103 | return -EOPNOTSUPP; |
104 | return 0; |
105 | } |
106 | |
107 | static int rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) |
108 | { |
109 | struct rtc_pll_info pll; |
110 | struct rtc_pll_info __user *argp = (void __user *)arg; |
111 | |
112 | switch (cmd) { |
113 | case RTC_PLL_GET: |
114 | if (!mach_get_rtc_pll || mach_get_rtc_pll(&pll)) |
115 | return -EINVAL; |
116 | return copy_to_user(argp, &pll, sizeof pll) ? -EFAULT : 0; |
117 | |
118 | case RTC_PLL_SET: |
119 | if (!mach_set_rtc_pll) |
120 | return -EINVAL; |
121 | if (!capable(CAP_SYS_TIME)) |
122 | return -EACCES; |
123 | if (copy_from_user(&pll, argp, sizeof(pll))) |
124 | return -EFAULT; |
125 | return mach_set_rtc_pll(&pll); |
126 | } |
127 | |
128 | return -ENOIOCTLCMD; |
129 | } |
130 | |
131 | static const struct rtc_class_ops generic_rtc_ops = { |
132 | .ioctl = rtc_ioctl, |
133 | .read_time = rtc_generic_get_time, |
134 | .set_time = rtc_generic_set_time, |
135 | }; |
136 | |
137 | static int __init rtc_init(void) |
138 | { |
139 | struct platform_device *pdev; |
140 | |
141 | if (!mach_hwclk) |
142 | return -ENODEV; |
143 | |
144 | pdev = platform_device_register_data(NULL, "rtc-generic" , -1, |
145 | &generic_rtc_ops, |
146 | sizeof(generic_rtc_ops)); |
147 | return PTR_ERR_OR_ZERO(pdev); |
148 | } |
149 | |
150 | module_init(rtc_init); |
151 | #endif /* CONFIG_RTC_DRV_GENERIC */ |
152 | #endif /* CONFIG M68KCLASSIC */ |
153 | |
154 | void __init time_init(void) |
155 | { |
156 | mach_sched_init(); |
157 | } |
158 | |