diff options
Diffstat (limited to 'arch/v850/kernel/time.c')
-rw-r--r-- | arch/v850/kernel/time.c | 198 |
1 files changed, 198 insertions, 0 deletions
diff --git a/arch/v850/kernel/time.c b/arch/v850/kernel/time.c new file mode 100644 index 000000000000..f722a268238a --- /dev/null +++ b/arch/v850/kernel/time.c | |||
@@ -0,0 +1,198 @@ | |||
1 | /* | ||
2 | * linux/arch/v850/kernel/time.c -- Arch-dependent timer functions | ||
3 | * | ||
4 | * Copyright (C) 1991, 1992, 1995, 2001, 2002 Linus Torvalds | ||
5 | * | ||
6 | * This file contains the v850-specific time handling details. | ||
7 | * Most of the stuff is located in the machine specific files. | ||
8 | * | ||
9 | * 1997-09-10 Updated NTP code according to technical memorandum Jan '96 | ||
10 | * "A Kernel Model for Precision Timekeeping" by Dave Mills | ||
11 | */ | ||
12 | |||
13 | #include <linux/config.h> /* CONFIG_HEARTBEAT */ | ||
14 | #include <linux/errno.h> | ||
15 | #include <linux/kernel.h> | ||
16 | #include <linux/module.h> | ||
17 | #include <linux/param.h> | ||
18 | #include <linux/string.h> | ||
19 | #include <linux/mm.h> | ||
20 | #include <linux/interrupt.h> | ||
21 | #include <linux/time.h> | ||
22 | #include <linux/timex.h> | ||
23 | #include <linux/profile.h> | ||
24 | |||
25 | #include <asm/io.h> | ||
26 | |||
27 | #include "mach.h" | ||
28 | |||
29 | u64 jiffies_64 = INITIAL_JIFFIES; | ||
30 | |||
31 | EXPORT_SYMBOL(jiffies_64); | ||
32 | |||
33 | #define TICK_SIZE (tick_nsec / 1000) | ||
34 | |||
35 | /* | ||
36 | * Scheduler clock - returns current time in nanosec units. | ||
37 | */ | ||
38 | unsigned long long sched_clock(void) | ||
39 | { | ||
40 | return (unsigned long long)jiffies * (1000000000 / HZ); | ||
41 | } | ||
42 | |||
43 | /* | ||
44 | * timer_interrupt() needs to keep up the real-time clock, | ||
45 | * as well as call the "do_timer()" routine every clocktick | ||
46 | */ | ||
47 | static irqreturn_t timer_interrupt (int irq, void *dummy, struct pt_regs *regs) | ||
48 | { | ||
49 | #if 0 | ||
50 | /* last time the cmos clock got updated */ | ||
51 | static long last_rtc_update=0; | ||
52 | #endif | ||
53 | |||
54 | /* may need to kick the hardware timer */ | ||
55 | if (mach_tick) | ||
56 | mach_tick (); | ||
57 | |||
58 | do_timer (regs); | ||
59 | #ifndef CONFIG_SMP | ||
60 | update_process_times(user_mode(regs)); | ||
61 | #endif | ||
62 | profile_tick(CPU_PROFILING, regs); | ||
63 | #if 0 | ||
64 | /* | ||
65 | * If we have an externally synchronized Linux clock, then update | ||
66 | * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be | ||
67 | * called as close as possible to 500 ms before the new second starts. | ||
68 | */ | ||
69 | if ((time_status & STA_UNSYNC) == 0 && | ||
70 | xtime.tv_sec > last_rtc_update + 660 && | ||
71 | (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 && | ||
72 | (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) { | ||
73 | if (set_rtc_mmss (xtime.tv_sec) == 0) | ||
74 | last_rtc_update = xtime.tv_sec; | ||
75 | else | ||
76 | last_rtc_update = xtime.tv_sec - 600; /* do it again in 60 s */ | ||
77 | } | ||
78 | #ifdef CONFIG_HEARTBEAT | ||
79 | /* use power LED as a heartbeat instead -- much more useful | ||
80 | for debugging -- based on the version for PReP by Cort */ | ||
81 | /* acts like an actual heart beat -- ie thump-thump-pause... */ | ||
82 | if (mach_heartbeat) { | ||
83 | static unsigned cnt = 0, period = 0, dist = 0; | ||
84 | |||
85 | if (cnt == 0 || cnt == dist) | ||
86 | mach_heartbeat ( 1 ); | ||
87 | else if (cnt == 7 || cnt == dist+7) | ||
88 | mach_heartbeat ( 0 ); | ||
89 | |||
90 | if (++cnt > period) { | ||
91 | cnt = 0; | ||
92 | /* The hyperbolic function below modifies the heartbeat period | ||
93 | * length in dependency of the current (5min) load. It goes | ||
94 | * through the points f(0)=126, f(1)=86, f(5)=51, | ||
95 | * f(inf)->30. */ | ||
96 | period = ((672<<FSHIFT)/(5*avenrun[0]+(7<<FSHIFT))) + 30; | ||
97 | dist = period / 4; | ||
98 | } | ||
99 | } | ||
100 | #endif /* CONFIG_HEARTBEAT */ | ||
101 | #endif /* 0 */ | ||
102 | |||
103 | return IRQ_HANDLED; | ||
104 | } | ||
105 | |||
106 | /* | ||
107 | * This version of gettimeofday has near microsecond resolution. | ||
108 | */ | ||
109 | void do_gettimeofday (struct timeval *tv) | ||
110 | { | ||
111 | #if 0 /* DAVIDM later if possible */ | ||
112 | extern volatile unsigned long lost_ticks; | ||
113 | unsigned long lost; | ||
114 | #endif | ||
115 | unsigned long flags; | ||
116 | unsigned long usec, sec; | ||
117 | unsigned long seq; | ||
118 | |||
119 | do { | ||
120 | seq = read_seqbegin_irqsave(&xtime_lock, flags); | ||
121 | |||
122 | #if 0 | ||
123 | usec = mach_gettimeoffset ? mach_gettimeoffset () : 0; | ||
124 | #else | ||
125 | usec = 0; | ||
126 | #endif | ||
127 | #if 0 /* DAVIDM later if possible */ | ||
128 | lost = lost_ticks; | ||
129 | if (lost) | ||
130 | usec += lost * (1000000/HZ); | ||
131 | #endif | ||
132 | sec = xtime.tv_sec; | ||
133 | usec += xtime.tv_nsec / 1000; | ||
134 | } while (read_seqretry_irqrestore(&xtime_lock, seq, flags)); | ||
135 | |||
136 | while (usec >= 1000000) { | ||
137 | usec -= 1000000; | ||
138 | sec++; | ||
139 | } | ||
140 | |||
141 | tv->tv_sec = sec; | ||
142 | tv->tv_usec = usec; | ||
143 | } | ||
144 | |||
145 | EXPORT_SYMBOL(do_gettimeofday); | ||
146 | |||
147 | int do_settimeofday(struct timespec *tv) | ||
148 | { | ||
149 | if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC) | ||
150 | return -EINVAL; | ||
151 | |||
152 | write_seqlock_irq (&xtime_lock); | ||
153 | |||
154 | /* This is revolting. We need to set the xtime.tv_nsec | ||
155 | * correctly. However, the value in this location is | ||
156 | * is value at the last tick. | ||
157 | * Discover what correction gettimeofday | ||
158 | * would have done, and then undo it! | ||
159 | */ | ||
160 | #if 0 | ||
161 | tv->tv_nsec -= mach_gettimeoffset() * 1000; | ||
162 | #endif | ||
163 | |||
164 | while (tv->tv_nsec < 0) { | ||
165 | tv->tv_nsec += NSEC_PER_SEC; | ||
166 | tv->tv_sec--; | ||
167 | } | ||
168 | |||
169 | xtime.tv_sec = tv->tv_sec; | ||
170 | xtime.tv_nsec = tv->tv_nsec; | ||
171 | |||
172 | time_adjust = 0; /* stop active adjtime () */ | ||
173 | time_status |= STA_UNSYNC; | ||
174 | time_maxerror = NTP_PHASE_LIMIT; | ||
175 | time_esterror = NTP_PHASE_LIMIT; | ||
176 | |||
177 | write_sequnlock_irq (&xtime_lock); | ||
178 | clock_was_set(); | ||
179 | return 0; | ||
180 | } | ||
181 | |||
182 | EXPORT_SYMBOL(do_settimeofday); | ||
183 | |||
184 | static int timer_dev_id; | ||
185 | static struct irqaction timer_irqaction = { | ||
186 | timer_interrupt, | ||
187 | SA_INTERRUPT, | ||
188 | CPU_MASK_NONE, | ||
189 | "timer", | ||
190 | &timer_dev_id, | ||
191 | NULL | ||
192 | }; | ||
193 | |||
194 | void time_init (void) | ||
195 | { | ||
196 | mach_gettimeofday (&xtime); | ||
197 | mach_sched_init (&timer_irqaction); | ||
198 | } | ||