1 // SPDX-License-Identifier: GPL-2.0-or-later <<
2 /* 1 /*
3 * Copyright 2001 MontaVista Software Inc. !! 2 * linux/arch/m68k/kernel/time.c
4 * Author: Jun Sun, jsun@mvista.com or jsun@ju <<
5 * Copyright (c) 2003, 2004 Maciej W. Rozycki <<
6 * 3 *
7 * Common time service routines for MIPS machi !! 4 * Copyright (C) 1991, 1992, 1995 Linus Torvalds
>> 5 *
>> 6 * This file contains the m68k-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
8 */ 11 */
9 #include <linux/bug.h> !! 12
10 #include <linux/clockchips.h> !! 13 #include <linux/config.h> /* CONFIG_HEARTBEAT */
11 #include <linux/types.h> !! 14 #include <linux/errno.h>
12 #include <linux/kernel.h> <<
13 #include <linux/init.h> <<
14 #include <linux/sched.h> 15 #include <linux/sched.h>
>> 16 #include <linux/kernel.h>
15 #include <linux/param.h> 17 #include <linux/param.h>
16 #include <linux/time.h> !! 18 #include <linux/string.h>
17 #include <linux/timex.h> !! 19 #include <linux/mm.h>
18 #include <linux/smp.h> <<
19 #include <linux/spinlock.h> <<
20 #include <linux/export.h> <<
21 #include <linux/cpufreq.h> <<
22 #include <linux/delay.h> <<
23 <<
24 #include <asm/cpu-features.h> <<
25 #include <asm/cpu-type.h> <<
26 #include <asm/div64.h> <<
27 #include <asm/time.h> <<
28 <<
29 #ifdef CONFIG_CPU_FREQ <<
30 <<
31 static DEFINE_PER_CPU(unsigned long, pcp_lpj_r <<
32 static DEFINE_PER_CPU(unsigned long, pcp_lpj_r <<
33 static unsigned long glb_lpj_ref; <<
34 static unsigned long glb_lpj_ref_freq; <<
35 <<
36 static int cpufreq_callback(struct notifier_bl <<
37 unsigned long val, <<
38 { <<
39 struct cpufreq_freqs *freq = data; <<
40 struct cpumask *cpus = freq->policy->c <<
41 unsigned long lpj; <<
42 int cpu; <<
43 <<
44 /* <<
45 * Skip lpj numbers adjustment if the <<
46 * the loops delay. (Is this possible? <<
47 */ <<
48 if (freq->flags & CPUFREQ_CONST_LOOPS) <<
49 return NOTIFY_OK; <<
50 20
51 /* Save the initial values of the lpje !! 21 #include <asm/machdep.h>
52 if (!glb_lpj_ref) { !! 22 #include <asm/io.h>
53 glb_lpj_ref = boot_cpu_data.ud <<
54 glb_lpj_ref_freq = freq->old; <<
55 <<
56 for_each_online_cpu(cpu) { <<
57 per_cpu(pcp_lpj_ref, c <<
58 cpu_data[cpu]. <<
59 per_cpu(pcp_lpj_ref_fr <<
60 } <<
61 } <<
62 <<
63 /* <<
64 * Adjust global lpj variable and per- <<
65 * accordance with the new CPU frequen <<
66 */ <<
67 if ((val == CPUFREQ_PRECHANGE && freq <<
68 (val == CPUFREQ_POSTCHANGE && freq <<
69 loops_per_jiffy = cpufreq_scal <<
70 <<
71 <<
72 <<
73 for_each_cpu(cpu, cpus) { <<
74 lpj = cpufreq_scale(pe <<
75 pe <<
76 fr <<
77 cpu_data[cpu].udelay_v <<
78 } <<
79 } <<
80 23
81 return NOTIFY_OK; !! 24 #include <linux/timex.h>
82 } <<
83 25
84 static struct notifier_block cpufreq_notifier <<
85 .notifier_call = cpufreq_callback, <<
86 }; <<
87 26
88 static int __init register_cpufreq_notifier(vo !! 27 static inline int set_rtc_mmss(unsigned long nowtime)
89 { 28 {
90 return cpufreq_register_notifier(&cpuf !! 29 if (mach_set_clock_mmss)
91 CPUFR !! 30 return mach_set_clock_mmss (nowtime);
>> 31 return -1;
92 } 32 }
93 core_initcall(register_cpufreq_notifier); <<
94 33
95 #endif /* CONFIG_CPU_FREQ */ !! 34 static inline void do_profile (unsigned long pc)
>> 35 {
>> 36 if (prof_buffer && current->pid) {
>> 37 extern int _stext;
>> 38 pc -= (unsigned long) &_stext;
>> 39 pc >>= prof_shift;
>> 40 if (pc < prof_len)
>> 41 ++prof_buffer[pc];
>> 42 else
>> 43 /*
>> 44 * Don't ignore out-of-bounds PC values silently,
>> 45 * put them into the last histogram slot, so if
>> 46 * present, they will show up as a sharp peak.
>> 47 */
>> 48 ++prof_buffer[prof_len-1];
>> 49 }
>> 50 }
96 51
97 /* 52 /*
98 * forward reference !! 53 * timer_interrupt() needs to keep up the real-time clock,
>> 54 * as well as call the "do_timer()" routine every clocktick
99 */ 55 */
100 DEFINE_SPINLOCK(rtc_lock); !! 56 static void timer_interrupt(int irq, void *dummy, struct pt_regs * regs)
101 EXPORT_SYMBOL(rtc_lock); <<
102 <<
103 static int null_perf_irq(void) <<
104 { 57 {
105 return 0; !! 58 do_timer(regs);
>> 59
>> 60 if (!user_mode(regs))
>> 61 do_profile(regs->pc);
>> 62
>> 63 #ifdef CONFIG_HEARTBEAT
>> 64 /* use power LED as a heartbeat instead -- much more useful
>> 65 for debugging -- based on the version for PReP by Cort */
>> 66 /* acts like an actual heart beat -- ie thump-thump-pause... */
>> 67 if (mach_heartbeat) {
>> 68 static unsigned cnt = 0, period = 0, dist = 0;
>> 69
>> 70 if (cnt == 0 || cnt == dist)
>> 71 mach_heartbeat( 1 );
>> 72 else if (cnt == 7 || cnt == dist+7)
>> 73 mach_heartbeat( 0 );
>> 74
>> 75 if (++cnt > period) {
>> 76 cnt = 0;
>> 77 /* The hyperbolic function below modifies the heartbeat period
>> 78 * length in dependency of the current (5min) load. It goes
>> 79 * through the points f(0)=126, f(1)=86, f(5)=51,
>> 80 * f(inf)->30. */
>> 81 period = ((672<<FSHIFT)/(5*avenrun[0]+(7<<FSHIFT))) + 30;
>> 82 dist = period / 4;
>> 83 }
>> 84 }
>> 85 #endif /* CONFIG_HEARTBEAT */
106 } 86 }
107 87
108 int (*perf_irq)(void) = null_perf_irq; !! 88 void time_init(void)
>> 89 {
>> 90 unsigned int year, mon, day, hour, min, sec;
109 91
110 EXPORT_SYMBOL(perf_irq); !! 92 extern void arch_gettod(int *year, int *mon, int *day, int *hour,
>> 93 int *min, int *sec);
111 94
112 /* !! 95 arch_gettod (&year, &mon, &day, &hour, &min, &sec);
113 * time_init() - it does the following things. <<
114 * <<
115 * 1) plat_time_init() - <<
116 * a) (optional) set up RTC routines, <<
117 * b) (optional) calibrate and set the mi <<
118 * (only needed if you intended to us <<
119 * source) <<
120 * 2) calculate a couple of cached variables f <<
121 */ <<
122 96
123 unsigned int mips_hpt_frequency; !! 97 if ((year += 1900) < 1970)
124 EXPORT_SYMBOL_GPL(mips_hpt_frequency); !! 98 year += 100;
>> 99 xtime.tv_sec = mktime(year, mon, day, hour, min, sec);
>> 100 xtime.tv_usec = 0;
125 101
126 static __init int cpu_has_mfc0_count_bug(void) !! 102 mach_sched_init(timer_interrupt);
127 { !! 103 }
128 switch (current_cpu_type()) { <<
129 case CPU_R4000PC: <<
130 case CPU_R4000SC: <<
131 case CPU_R4000MC: <<
132 /* <<
133 * V3.0 is documented as suffe <<
134 * Afaik this is the last vers <<
135 * were marketed as R4400. <<
136 */ <<
137 return 1; <<
138 104
139 case CPU_R4400PC: !! 105 extern rwlock_t xtime_lock;
140 case CPU_R4400SC: !! 106
141 case CPU_R4400MC: !! 107 /*
142 /* !! 108 * This version of gettimeofday has near microsecond resolution.
143 * The published errata for th !! 109 */
144 * has the mfc0 from count bug !! 110 void do_gettimeofday(struct timeval *tv)
145 * produced. !! 111 {
146 */ !! 112 extern unsigned long wall_jiffies;
147 return 1; !! 113 unsigned long flags;
>> 114 unsigned long usec, sec, lost;
>> 115
>> 116 read_lock_irqsave(&xtime_lock, flags);
>> 117 usec = mach_gettimeoffset();
>> 118 lost = jiffies - wall_jiffies;
>> 119 if (lost)
>> 120 usec += lost * (1000000/HZ);
>> 121 sec = xtime.tv_sec;
>> 122 usec += xtime.tv_usec;
>> 123 read_unlock_irqrestore(&xtime_lock, flags);
>> 124
>> 125 while (usec >= 1000000) {
>> 126 usec -= 1000000;
>> 127 sec++;
148 } 128 }
149 129
150 return 0; !! 130 tv->tv_sec = sec;
>> 131 tv->tv_usec = usec;
151 } 132 }
152 133
153 void __init time_init(void) !! 134 void do_settimeofday(struct timeval *tv)
154 { 135 {
155 plat_time_init(); !! 136 write_lock_irq(&xtime_lock);
156 !! 137 /* This is revolting. We need to set the xtime.tv_usec
157 /* !! 138 * correctly. However, the value in this location is
158 * The use of the R4k timer as a clock !! 139 * is value at the last tick.
159 * if reading the Count register might !! 140 * Discover what correction gettimeofday
160 * interrupt, then we don't use the ti !! 141 * would have done, and then undo it!
161 * We may still use the timer as a clo <<
162 * timer interrupt isn't reliable; the <<
163 * matter then, because we don't use t <<
164 */ 142 */
165 if (mips_clockevent_init() != 0 || !cp !! 143 tv->tv_usec -= mach_gettimeoffset();
166 init_mips_clocksource(); !! 144
>> 145 while (tv->tv_usec < 0) {
>> 146 tv->tv_usec += 1000000;
>> 147 tv->tv_sec--;
>> 148 }
>> 149
>> 150 xtime = *tv;
>> 151 time_adjust = 0; /* stop active adjtime() */
>> 152 time_status |= STA_UNSYNC;
>> 153 time_maxerror = NTP_PHASE_LIMIT;
>> 154 time_esterror = NTP_PHASE_LIMIT;
>> 155 write_unlock_irq(&xtime_lock);
167 } 156 }
168 157
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