1 /*
2 * Copyright (c) 2006-2022 Ali Mashtizadeh
3 * All rights reserved.
4 */
5
6 #include <stdbool.h>
7 #include <stdint.h>
8
9 #include <sys/kassert.h>
10 #include <sys/kdebug.h>
11 #include <sys/ktime.h>
12 #include <sys/spinlock.h>
13
14 static Spinlock ktimeLock;
15 static uint64_t ktimeLastEpoch;
16 static uint64_t ktimeLastTSC;
17 uint64_t ticksPerSecond;
18
19 static const char *dayOfWeek[7] = { "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" };
20 static const char *months[12] = {
21 "Jan", "Feb", "Mar", "Apr", "May", "Jun",
22 "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
23 };
24
25 void
KTime_Init()26 KTime_Init()
27 {
28 Spinlock_Init(&ktimeLock, "KTime Lock", SPINLOCK_TYPE_NORMAL);
29 ktimeLastEpoch = 0;
30 ktimeLastTSC = 0;
31 ticksPerSecond = 0;
32 }
33
34 static bool
KTimeIsLeapYear(uint64_t year)35 KTimeIsLeapYear(uint64_t year)
36 {
37 if ((year % 4) != 0)
38 return false;
39 if ((year % 100) != 0)
40 return true;
41 if ((year % 400) != 0)
42 return false;
43 return true;
44 }
45
46 static int
KTimeDaysInMonth(uint64_t year,uint64_t month)47 KTimeDaysInMonth(uint64_t year, uint64_t month)
48 {
49 static const uint64_t days[12] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
50
51 if ((month == 2) && KTimeIsLeapYear(year))
52 return 29;
53 else
54 return days[month];
55 }
56
57 /*
58 * This function recomputes yday, mday or wday given other fields
59 */
60 void
KTime_Fixup(KTime * tm)61 KTime_Fixup(KTime *tm)
62 {
63 uint64_t m;
64
65 if (tm->yday == -1) {
66 uint64_t yday = 0;
67 for (m = 0; m < tm->month; m++) {
68 yday += KTimeDaysInMonth(tm->year, m);
69 }
70 yday += tm->mday;
71 tm->yday = yday;
72 }
73 }
74
75 UnixEpoch
KTime_ToEpoch(const KTime * tm)76 KTime_ToEpoch(const KTime *tm)
77 {
78 uint64_t days = 0;
79 uint64_t secs = 0;
80 uint64_t y, m;
81
82 // Convert to UNIX epoch
83 for (y = 1970; y < tm->year; y++) {
84 if (KTimeIsLeapYear(y))
85 days += 366;
86 else
87 days += 365;
88 }
89
90 if (tm->yday == -1) {
91 uint64_t yday = 0;
92 for (m = 0; m < tm->month; m++) {
93 yday += KTimeDaysInMonth(tm->year, m);
94 }
95 yday += tm->mday;
96 days += yday;
97 } else {
98 days += tm->yday;
99 }
100
101 secs = 24 * days + tm->hour;
102 secs = secs * 60 + tm->min;
103 secs = secs * 60 + tm->sec;
104
105 return secs;
106 }
107
108 void
KTime_FromEpoch(UnixEpoch epoch,KTime * tm)109 KTime_FromEpoch(UnixEpoch epoch, KTime *tm)
110 {
111 uint64_t secs, mins, hours;
112 uint64_t days;
113 uint64_t y, m;
114
115 // Compute seconds
116 secs = epoch % (60 * 60 * 24);
117 days = epoch / (60 * 60 * 24);
118 mins = secs / 60;
119 secs = secs % 60;
120
121 // Compute minutes
122 hours = mins / 60;
123 mins = mins % 60;
124
125 // Compute hours
126 hours = hours % 24;
127
128 tm->sec = secs;
129 tm->min = mins;
130 tm->hour = hours;
131
132 tm->wday = (days + 3) % 7;
133
134 for (y = 1970; ; y++) {
135 uint64_t daysOfYear;
136 if (KTimeIsLeapYear(y)) {
137 daysOfYear = 366;
138 } else {
139 daysOfYear = 365;
140 }
141
142 if (days < daysOfYear) {
143 tm->yday = days;
144 tm->year = y;
145 break;
146 }
147 days -= daysOfYear;
148 }
149
150 for (m = 0; ; m++) {
151 uint64_t daysOfMonth = KTimeDaysInMonth(tm->year, m);
152
153 if (days < daysOfMonth) {
154 tm->mday = days;
155 tm->month = m;
156 break;
157 }
158 days -= daysOfMonth;
159 }
160 }
161
162 void
KTime_SetTime(UnixEpoch epoch,uint64_t tsc,uint64_t tps)163 KTime_SetTime(UnixEpoch epoch, uint64_t tsc, uint64_t tps)
164 {
165 Spinlock_Lock(&ktimeLock);
166 ktimeLastEpoch = epoch;
167 ktimeLastTSC = tsc;
168 ticksPerSecond = tps;
169 Spinlock_Unlock(&ktimeLock);
170
171 }
172
173 void
KTime_GetTime(KTime * tm)174 KTime_GetTime(KTime *tm)
175 {
176 KTime_FromEpoch(KTime_GetEpoch(), tm);
177 }
178
179 UnixEpoch
KTime_GetEpoch()180 KTime_GetEpoch()
181 {
182 uint64_t tscDiff;
183 uint64_t epoch;
184
185 Spinlock_Lock(&ktimeLock);
186 tscDiff = Time_GetTSC() - ktimeLastTSC;
187 epoch = ktimeLastEpoch + tscDiff / ticksPerSecond;
188 Spinlock_Unlock(&ktimeLock);
189
190 return epoch;
191 }
192
193 UnixEpochNS
KTime_GetEpochNS()194 KTime_GetEpochNS()
195 {
196 uint64_t tscDiff;
197 uint64_t epoch;
198
199 Spinlock_Lock(&ktimeLock);
200 tscDiff = Time_GetTSC() - ktimeLastTSC;
201 /*
202 * This is ugly but it avoids overflowing tscDiff to time computation.
203 * Note that the bottom bits of ticksPerSecond are not significant so it is
204 * okay to discard them.
205 */
206 epoch = (ktimeLastEpoch * 1000000000ULL) + (tscDiff * 1000000ULL / ticksPerSecond * 1000ULL);
207 Spinlock_Unlock(&ktimeLock);
208
209 return epoch;
210 }
211
212 static void
Debug_Date()213 Debug_Date()
214 {
215 UnixEpoch epoch = KTime_GetEpoch();
216 KTime tm;
217
218 KTime_FromEpoch(epoch, &tm);
219
220 kprintf("%s %s %d %02d:%02d:%02d %04d\n",
221 dayOfWeek[tm.wday], months[tm.month],
222 tm.mday, tm.hour, tm.min, tm.sec, tm.year);
223
224 kprintf("Epoch: %lu\n", epoch);
225 }
226
227 REGISTER_DBGCMD(date, "Print date", Debug_Date);
228
229 static void
Debug_Ticks()230 Debug_Ticks()
231 {
232 kprintf("Ticks Per Second: %lu\n", ticksPerSecond);
233 }
234
235 REGISTER_DBGCMD(ticks, "Print ticks per second", Debug_Ticks);
236
237