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Commit | Line | Data |
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1da177e4 | 1 | /* |
1da177e4 LT |
2 | * Common time routines among all ppc machines. |
3 | * | |
4 | * Written by Cort Dougan (cort@cs.nmt.edu) to merge | |
5 | * Paul Mackerras' version and mine for PReP and Pmac. | |
6 | * MPC8xx/MBX changes by Dan Malek (dmalek@jlc.net). | |
7 | * Converted for 64-bit by Mike Corrigan (mikejc@us.ibm.com) | |
8 | * | |
9 | * First round of bugfixes by Gabriel Paubert (paubert@iram.es) | |
10 | * to make clock more stable (2.4.0-test5). The only thing | |
11 | * that this code assumes is that the timebases have been synchronized | |
12 | * by firmware on SMP and are never stopped (never do sleep | |
13 | * on SMP then, nap and doze are OK). | |
14 | * | |
15 | * Speeded up do_gettimeofday by getting rid of references to | |
16 | * xtime (which required locks for consistency). (mikejc@us.ibm.com) | |
17 | * | |
18 | * TODO (not necessarily in this file): | |
19 | * - improve precision and reproducibility of timebase frequency | |
f5339277 | 20 | * measurement at boot time. |
1da177e4 LT |
21 | * - for astronomical applications: add a new function to get |
22 | * non ambiguous timestamps even around leap seconds. This needs | |
23 | * a new timestamp format and a good name. | |
24 | * | |
25 | * 1997-09-10 Updated NTP code according to technical memorandum Jan '96 | |
26 | * "A Kernel Model for Precision Timekeeping" by Dave Mills | |
27 | * | |
28 | * This program is free software; you can redistribute it and/or | |
29 | * modify it under the terms of the GNU General Public License | |
30 | * as published by the Free Software Foundation; either version | |
31 | * 2 of the License, or (at your option) any later version. | |
32 | */ | |
33 | ||
1da177e4 | 34 | #include <linux/errno.h> |
4b16f8e2 | 35 | #include <linux/export.h> |
1da177e4 LT |
36 | #include <linux/sched.h> |
37 | #include <linux/kernel.h> | |
38 | #include <linux/param.h> | |
39 | #include <linux/string.h> | |
40 | #include <linux/mm.h> | |
41 | #include <linux/interrupt.h> | |
42 | #include <linux/timex.h> | |
43 | #include <linux/kernel_stat.h> | |
1da177e4 LT |
44 | #include <linux/time.h> |
45 | #include <linux/init.h> | |
46 | #include <linux/profile.h> | |
47 | #include <linux/cpu.h> | |
48 | #include <linux/security.h> | |
f2783c15 PM |
49 | #include <linux/percpu.h> |
50 | #include <linux/rtc.h> | |
092b8f34 | 51 | #include <linux/jiffies.h> |
c6622f63 | 52 | #include <linux/posix-timers.h> |
7d12e780 | 53 | #include <linux/irq.h> |
177996e6 | 54 | #include <linux/delay.h> |
e360adbe | 55 | #include <linux/irq_work.h> |
6795b85c | 56 | #include <asm/trace.h> |
1da177e4 | 57 | |
1da177e4 LT |
58 | #include <asm/io.h> |
59 | #include <asm/processor.h> | |
60 | #include <asm/nvram.h> | |
61 | #include <asm/cache.h> | |
62 | #include <asm/machdep.h> | |
1da177e4 LT |
63 | #include <asm/uaccess.h> |
64 | #include <asm/time.h> | |
1da177e4 | 65 | #include <asm/prom.h> |
f2783c15 PM |
66 | #include <asm/irq.h> |
67 | #include <asm/div64.h> | |
2249ca9d | 68 | #include <asm/smp.h> |
a7f290da | 69 | #include <asm/vdso_datapage.h> |
1ababe11 | 70 | #include <asm/firmware.h> |
06b8e878 | 71 | #include <asm/cputime.h> |
1da177e4 | 72 | |
4a4cfe38 TB |
73 | /* powerpc clocksource/clockevent code */ |
74 | ||
d831d0b8 | 75 | #include <linux/clockchips.h> |
189374ae | 76 | #include <linux/timekeeper_internal.h> |
4a4cfe38 | 77 | |
8e19608e | 78 | static cycle_t rtc_read(struct clocksource *); |
4a4cfe38 TB |
79 | static struct clocksource clocksource_rtc = { |
80 | .name = "rtc", | |
81 | .rating = 400, | |
82 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | |
83 | .mask = CLOCKSOURCE_MASK(64), | |
4a4cfe38 TB |
84 | .read = rtc_read, |
85 | }; | |
86 | ||
8e19608e | 87 | static cycle_t timebase_read(struct clocksource *); |
4a4cfe38 TB |
88 | static struct clocksource clocksource_timebase = { |
89 | .name = "timebase", | |
90 | .rating = 400, | |
91 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | |
92 | .mask = CLOCKSOURCE_MASK(64), | |
4a4cfe38 TB |
93 | .read = timebase_read, |
94 | }; | |
95 | ||
d831d0b8 TB |
96 | #define DECREMENTER_MAX 0x7fffffff |
97 | ||
98 | static int decrementer_set_next_event(unsigned long evt, | |
99 | struct clock_event_device *dev); | |
100 | static void decrementer_set_mode(enum clock_event_mode mode, | |
101 | struct clock_event_device *dev); | |
102 | ||
6e35994d | 103 | struct clock_event_device decrementer_clockevent = { |
621692cb AB |
104 | .name = "decrementer", |
105 | .rating = 200, | |
106 | .irq = 0, | |
107 | .set_next_event = decrementer_set_next_event, | |
108 | .set_mode = decrementer_set_mode, | |
109 | .features = CLOCK_EVT_FEAT_ONESHOT, | |
d831d0b8 | 110 | }; |
6e35994d | 111 | EXPORT_SYMBOL(decrementer_clockevent); |
d831d0b8 | 112 | |
7df10275 AB |
113 | DEFINE_PER_CPU(u64, decrementers_next_tb); |
114 | static DEFINE_PER_CPU(struct clock_event_device, decrementers); | |
d831d0b8 | 115 | |
1da177e4 LT |
116 | #define XSEC_PER_SEC (1024*1024) |
117 | ||
f2783c15 PM |
118 | #ifdef CONFIG_PPC64 |
119 | #define SCALE_XSEC(xsec, max) (((xsec) * max) / XSEC_PER_SEC) | |
120 | #else | |
121 | /* compute ((xsec << 12) * max) >> 32 */ | |
122 | #define SCALE_XSEC(xsec, max) mulhwu((xsec) << 12, max) | |
123 | #endif | |
124 | ||
1da177e4 LT |
125 | unsigned long tb_ticks_per_jiffy; |
126 | unsigned long tb_ticks_per_usec = 100; /* sane default */ | |
127 | EXPORT_SYMBOL(tb_ticks_per_usec); | |
128 | unsigned long tb_ticks_per_sec; | |
2cf82c02 | 129 | EXPORT_SYMBOL(tb_ticks_per_sec); /* for cputime_t conversions */ |
092b8f34 | 130 | |
1da177e4 | 131 | DEFINE_SPINLOCK(rtc_lock); |
6ae3db11 | 132 | EXPORT_SYMBOL_GPL(rtc_lock); |
1da177e4 | 133 | |
fc9069fe TB |
134 | static u64 tb_to_ns_scale __read_mostly; |
135 | static unsigned tb_to_ns_shift __read_mostly; | |
364a1246 | 136 | static u64 boot_tb __read_mostly; |
1da177e4 | 137 | |
1da177e4 | 138 | extern struct timezone sys_tz; |
f2783c15 | 139 | static long timezone_offset; |
1da177e4 | 140 | |
10f7e7c1 | 141 | unsigned long ppc_proc_freq; |
55ec2fca | 142 | EXPORT_SYMBOL_GPL(ppc_proc_freq); |
10f7e7c1 | 143 | unsigned long ppc_tb_freq; |
55ec2fca | 144 | EXPORT_SYMBOL_GPL(ppc_tb_freq); |
96c44507 | 145 | |
abf917cd | 146 | #ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE |
c6622f63 PM |
147 | /* |
148 | * Factors for converting from cputime_t (timebase ticks) to | |
9f5072d4 | 149 | * jiffies, microseconds, seconds, and clock_t (1/USER_HZ seconds). |
c6622f63 PM |
150 | * These are all stored as 0.64 fixed-point binary fractions. |
151 | */ | |
152 | u64 __cputime_jiffies_factor; | |
2cf82c02 | 153 | EXPORT_SYMBOL(__cputime_jiffies_factor); |
9f5072d4 AS |
154 | u64 __cputime_usec_factor; |
155 | EXPORT_SYMBOL(__cputime_usec_factor); | |
c6622f63 | 156 | u64 __cputime_sec_factor; |
2cf82c02 | 157 | EXPORT_SYMBOL(__cputime_sec_factor); |
c6622f63 | 158 | u64 __cputime_clockt_factor; |
2cf82c02 | 159 | EXPORT_SYMBOL(__cputime_clockt_factor); |
06b8e878 MN |
160 | DEFINE_PER_CPU(unsigned long, cputime_last_delta); |
161 | DEFINE_PER_CPU(unsigned long, cputime_scaled_last_delta); | |
c6622f63 | 162 | |
a42548a1 SG |
163 | cputime_t cputime_one_jiffy; |
164 | ||
872e439a PM |
165 | void (*dtl_consumer)(struct dtl_entry *, u64); |
166 | ||
c6622f63 PM |
167 | static void calc_cputime_factors(void) |
168 | { | |
169 | struct div_result res; | |
170 | ||
171 | div128_by_32(HZ, 0, tb_ticks_per_sec, &res); | |
172 | __cputime_jiffies_factor = res.result_low; | |
9f5072d4 AS |
173 | div128_by_32(1000000, 0, tb_ticks_per_sec, &res); |
174 | __cputime_usec_factor = res.result_low; | |
c6622f63 PM |
175 | div128_by_32(1, 0, tb_ticks_per_sec, &res); |
176 | __cputime_sec_factor = res.result_low; | |
177 | div128_by_32(USER_HZ, 0, tb_ticks_per_sec, &res); | |
178 | __cputime_clockt_factor = res.result_low; | |
179 | } | |
180 | ||
181 | /* | |
cf9efce0 PM |
182 | * Read the SPURR on systems that have it, otherwise the PURR, |
183 | * or if that doesn't exist return the timebase value passed in. | |
c6622f63 | 184 | */ |
cf9efce0 | 185 | static u64 read_spurr(u64 tb) |
c6622f63 | 186 | { |
cf9efce0 PM |
187 | if (cpu_has_feature(CPU_FTR_SPURR)) |
188 | return mfspr(SPRN_SPURR); | |
c6622f63 PM |
189 | if (cpu_has_feature(CPU_FTR_PURR)) |
190 | return mfspr(SPRN_PURR); | |
cf9efce0 | 191 | return tb; |
c6622f63 PM |
192 | } |
193 | ||
cf9efce0 PM |
194 | #ifdef CONFIG_PPC_SPLPAR |
195 | ||
4603ac18 | 196 | /* |
cf9efce0 PM |
197 | * Scan the dispatch trace log and count up the stolen time. |
198 | * Should be called with interrupts disabled. | |
4603ac18 | 199 | */ |
cf9efce0 | 200 | static u64 scan_dispatch_log(u64 stop_tb) |
4603ac18 | 201 | { |
872e439a | 202 | u64 i = local_paca->dtl_ridx; |
cf9efce0 PM |
203 | struct dtl_entry *dtl = local_paca->dtl_curr; |
204 | struct dtl_entry *dtl_end = local_paca->dispatch_log_end; | |
205 | struct lppaca *vpa = local_paca->lppaca_ptr; | |
206 | u64 tb_delta; | |
207 | u64 stolen = 0; | |
208 | u64 dtb; | |
209 | ||
84ffae55 AB |
210 | if (!dtl) |
211 | return 0; | |
212 | ||
7ffcf8ec | 213 | if (i == be64_to_cpu(vpa->dtl_idx)) |
cf9efce0 | 214 | return 0; |
7ffcf8ec | 215 | while (i < be64_to_cpu(vpa->dtl_idx)) { |
7ffcf8ec AB |
216 | dtb = be64_to_cpu(dtl->timebase); |
217 | tb_delta = be32_to_cpu(dtl->enqueue_to_dispatch_time) + | |
218 | be32_to_cpu(dtl->ready_to_enqueue_time); | |
cf9efce0 | 219 | barrier(); |
7ffcf8ec | 220 | if (i + N_DISPATCH_LOG < be64_to_cpu(vpa->dtl_idx)) { |
cf9efce0 | 221 | /* buffer has overflowed */ |
7ffcf8ec | 222 | i = be64_to_cpu(vpa->dtl_idx) - N_DISPATCH_LOG; |
cf9efce0 PM |
223 | dtl = local_paca->dispatch_log + (i % N_DISPATCH_LOG); |
224 | continue; | |
225 | } | |
226 | if (dtb > stop_tb) | |
227 | break; | |
84b07386 AB |
228 | if (dtl_consumer) |
229 | dtl_consumer(dtl, i); | |
cf9efce0 PM |
230 | stolen += tb_delta; |
231 | ++i; | |
232 | ++dtl; | |
233 | if (dtl == dtl_end) | |
234 | dtl = local_paca->dispatch_log; | |
235 | } | |
236 | local_paca->dtl_ridx = i; | |
237 | local_paca->dtl_curr = dtl; | |
238 | return stolen; | |
4603ac18 MN |
239 | } |
240 | ||
cf9efce0 PM |
241 | /* |
242 | * Accumulate stolen time by scanning the dispatch trace log. | |
243 | * Called on entry from user mode. | |
244 | */ | |
245 | void accumulate_stolen_time(void) | |
246 | { | |
247 | u64 sst, ust; | |
248 | ||
b18ae08d | 249 | u8 save_soft_enabled = local_paca->soft_enabled; |
b18ae08d TH |
250 | |
251 | /* We are called early in the exception entry, before | |
252 | * soft/hard_enabled are sync'ed to the expected state | |
253 | * for the exception. We are hard disabled but the PACA | |
254 | * needs to reflect that so various debug stuff doesn't | |
255 | * complain | |
256 | */ | |
257 | local_paca->soft_enabled = 0; | |
b18ae08d TH |
258 | |
259 | sst = scan_dispatch_log(local_paca->starttime_user); | |
260 | ust = scan_dispatch_log(local_paca->starttime); | |
261 | local_paca->system_time -= sst; | |
262 | local_paca->user_time -= ust; | |
263 | local_paca->stolen_time += ust + sst; | |
264 | ||
265 | local_paca->soft_enabled = save_soft_enabled; | |
cf9efce0 PM |
266 | } |
267 | ||
268 | static inline u64 calculate_stolen_time(u64 stop_tb) | |
269 | { | |
270 | u64 stolen = 0; | |
271 | ||
7ffcf8ec | 272 | if (get_paca()->dtl_ridx != be64_to_cpu(get_lppaca()->dtl_idx)) { |
cf9efce0 PM |
273 | stolen = scan_dispatch_log(stop_tb); |
274 | get_paca()->system_time -= stolen; | |
275 | } | |
276 | ||
277 | stolen += get_paca()->stolen_time; | |
278 | get_paca()->stolen_time = 0; | |
279 | return stolen; | |
4603ac18 MN |
280 | } |
281 | ||
cf9efce0 PM |
282 | #else /* CONFIG_PPC_SPLPAR */ |
283 | static inline u64 calculate_stolen_time(u64 stop_tb) | |
284 | { | |
285 | return 0; | |
286 | } | |
287 | ||
288 | #endif /* CONFIG_PPC_SPLPAR */ | |
289 | ||
c6622f63 PM |
290 | /* |
291 | * Account time for a transition between system, hard irq | |
292 | * or soft irq state. | |
293 | */ | |
a7e1a9e3 FW |
294 | static u64 vtime_delta(struct task_struct *tsk, |
295 | u64 *sys_scaled, u64 *stolen) | |
c6622f63 | 296 | { |
a7e1a9e3 FW |
297 | u64 now, nowscaled, deltascaled; |
298 | u64 udelta, delta, user_scaled; | |
c6622f63 | 299 | |
1b2852b1 FW |
300 | WARN_ON_ONCE(!irqs_disabled()); |
301 | ||
cf9efce0 | 302 | now = mftb(); |
4603ac18 | 303 | nowscaled = read_spurr(now); |
cf9efce0 PM |
304 | get_paca()->system_time += now - get_paca()->starttime; |
305 | get_paca()->starttime = now; | |
4603ac18 MN |
306 | deltascaled = nowscaled - get_paca()->startspurr; |
307 | get_paca()->startspurr = nowscaled; | |
cf9efce0 | 308 | |
a7e1a9e3 | 309 | *stolen = calculate_stolen_time(now); |
cf9efce0 PM |
310 | |
311 | delta = get_paca()->system_time; | |
312 | get_paca()->system_time = 0; | |
313 | udelta = get_paca()->user_time - get_paca()->utime_sspurr; | |
314 | get_paca()->utime_sspurr = get_paca()->user_time; | |
315 | ||
316 | /* | |
317 | * Because we don't read the SPURR on every kernel entry/exit, | |
318 | * deltascaled includes both user and system SPURR ticks. | |
319 | * Apportion these ticks to system SPURR ticks and user | |
320 | * SPURR ticks in the same ratio as the system time (delta) | |
321 | * and user time (udelta) values obtained from the timebase | |
322 | * over the same interval. The system ticks get accounted here; | |
323 | * the user ticks get saved up in paca->user_time_scaled to be | |
324 | * used by account_process_tick. | |
325 | */ | |
a7e1a9e3 | 326 | *sys_scaled = delta; |
cf9efce0 PM |
327 | user_scaled = udelta; |
328 | if (deltascaled != delta + udelta) { | |
329 | if (udelta) { | |
a7e1a9e3 FW |
330 | *sys_scaled = deltascaled * delta / (delta + udelta); |
331 | user_scaled = deltascaled - *sys_scaled; | |
cf9efce0 | 332 | } else { |
a7e1a9e3 | 333 | *sys_scaled = deltascaled; |
cf9efce0 PM |
334 | } |
335 | } | |
336 | get_paca()->user_time_scaled += user_scaled; | |
337 | ||
a7e1a9e3 FW |
338 | return delta; |
339 | } | |
340 | ||
fd25b4c2 | 341 | void vtime_account_system(struct task_struct *tsk) |
a7e1a9e3 FW |
342 | { |
343 | u64 delta, sys_scaled, stolen; | |
344 | ||
345 | delta = vtime_delta(tsk, &sys_scaled, &stolen); | |
346 | account_system_time(tsk, 0, delta, sys_scaled); | |
347 | if (stolen) | |
348 | account_steal_time(stolen); | |
349 | } | |
c11f11fc | 350 | EXPORT_SYMBOL_GPL(vtime_account_system); |
a7e1a9e3 | 351 | |
fd25b4c2 | 352 | void vtime_account_idle(struct task_struct *tsk) |
a7e1a9e3 FW |
353 | { |
354 | u64 delta, sys_scaled, stolen; | |
355 | ||
356 | delta = vtime_delta(tsk, &sys_scaled, &stolen); | |
357 | account_idle_time(delta + stolen); | |
c6622f63 PM |
358 | } |
359 | ||
360 | /* | |
bcebdf84 FW |
361 | * Transfer the user time accumulated in the paca |
362 | * by the exception entry and exit code to the generic | |
363 | * process user time records. | |
c6622f63 | 364 | * Must be called with interrupts disabled. |
bcebdf84 FW |
365 | * Assumes that vtime_account_system/idle() has been called |
366 | * recently (i.e. since the last entry from usermode) so that | |
cf9efce0 | 367 | * get_paca()->user_time_scaled is up to date. |
c6622f63 | 368 | */ |
bcebdf84 | 369 | void vtime_account_user(struct task_struct *tsk) |
c6622f63 | 370 | { |
4603ac18 | 371 | cputime_t utime, utimescaled; |
c6622f63 PM |
372 | |
373 | utime = get_paca()->user_time; | |
cf9efce0 | 374 | utimescaled = get_paca()->user_time_scaled; |
c6622f63 | 375 | get_paca()->user_time = 0; |
cf9efce0 PM |
376 | get_paca()->user_time_scaled = 0; |
377 | get_paca()->utime_sspurr = 0; | |
457533a7 | 378 | account_user_time(tsk, utime, utimescaled); |
c6622f63 PM |
379 | } |
380 | ||
abf917cd | 381 | #else /* ! CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ |
c6622f63 | 382 | #define calc_cputime_factors() |
c6622f63 PM |
383 | #endif |
384 | ||
6defa38b PM |
385 | void __delay(unsigned long loops) |
386 | { | |
387 | unsigned long start; | |
388 | int diff; | |
389 | ||
390 | if (__USE_RTC()) { | |
391 | start = get_rtcl(); | |
392 | do { | |
393 | /* the RTCL register wraps at 1000000000 */ | |
394 | diff = get_rtcl() - start; | |
395 | if (diff < 0) | |
396 | diff += 1000000000; | |
397 | } while (diff < loops); | |
398 | } else { | |
399 | start = get_tbl(); | |
400 | while (get_tbl() - start < loops) | |
401 | HMT_low(); | |
402 | HMT_medium(); | |
403 | } | |
404 | } | |
405 | EXPORT_SYMBOL(__delay); | |
406 | ||
407 | void udelay(unsigned long usecs) | |
408 | { | |
409 | __delay(tb_ticks_per_usec * usecs); | |
410 | } | |
411 | EXPORT_SYMBOL(udelay); | |
412 | ||
1da177e4 LT |
413 | #ifdef CONFIG_SMP |
414 | unsigned long profile_pc(struct pt_regs *regs) | |
415 | { | |
416 | unsigned long pc = instruction_pointer(regs); | |
417 | ||
418 | if (in_lock_functions(pc)) | |
419 | return regs->link; | |
420 | ||
421 | return pc; | |
422 | } | |
423 | EXPORT_SYMBOL(profile_pc); | |
424 | #endif | |
425 | ||
e360adbe | 426 | #ifdef CONFIG_IRQ_WORK |
105988c0 | 427 | |
0fe1ac48 PM |
428 | /* |
429 | * 64-bit uses a byte in the PACA, 32-bit uses a per-cpu variable... | |
430 | */ | |
431 | #ifdef CONFIG_PPC64 | |
e360adbe | 432 | static inline unsigned long test_irq_work_pending(void) |
105988c0 | 433 | { |
0fe1ac48 PM |
434 | unsigned long x; |
435 | ||
436 | asm volatile("lbz %0,%1(13)" | |
437 | : "=r" (x) | |
e360adbe | 438 | : "i" (offsetof(struct paca_struct, irq_work_pending))); |
0fe1ac48 PM |
439 | return x; |
440 | } | |
441 | ||
e360adbe | 442 | static inline void set_irq_work_pending_flag(void) |
0fe1ac48 PM |
443 | { |
444 | asm volatile("stb %0,%1(13)" : : | |
445 | "r" (1), | |
e360adbe | 446 | "i" (offsetof(struct paca_struct, irq_work_pending))); |
0fe1ac48 PM |
447 | } |
448 | ||
e360adbe | 449 | static inline void clear_irq_work_pending(void) |
0fe1ac48 PM |
450 | { |
451 | asm volatile("stb %0,%1(13)" : : | |
452 | "r" (0), | |
e360adbe | 453 | "i" (offsetof(struct paca_struct, irq_work_pending))); |
105988c0 PM |
454 | } |
455 | ||
0fe1ac48 PM |
456 | #else /* 32-bit */ |
457 | ||
e360adbe | 458 | DEFINE_PER_CPU(u8, irq_work_pending); |
0fe1ac48 | 459 | |
e360adbe PZ |
460 | #define set_irq_work_pending_flag() __get_cpu_var(irq_work_pending) = 1 |
461 | #define test_irq_work_pending() __get_cpu_var(irq_work_pending) | |
462 | #define clear_irq_work_pending() __get_cpu_var(irq_work_pending) = 0 | |
105988c0 | 463 | |
0fe1ac48 PM |
464 | #endif /* 32 vs 64 bit */ |
465 | ||
4f8b50bb | 466 | void arch_irq_work_raise(void) |
0fe1ac48 PM |
467 | { |
468 | preempt_disable(); | |
e360adbe | 469 | set_irq_work_pending_flag(); |
0fe1ac48 PM |
470 | set_dec(1); |
471 | preempt_enable(); | |
472 | } | |
473 | ||
e360adbe | 474 | #else /* CONFIG_IRQ_WORK */ |
105988c0 | 475 | |
e360adbe PZ |
476 | #define test_irq_work_pending() 0 |
477 | #define clear_irq_work_pending() | |
105988c0 | 478 | |
e360adbe | 479 | #endif /* CONFIG_IRQ_WORK */ |
105988c0 | 480 | |
1da177e4 LT |
481 | /* |
482 | * timer_interrupt - gets called when the decrementer overflows, | |
483 | * with interrupts disabled. | |
484 | */ | |
c7aeffc4 | 485 | void timer_interrupt(struct pt_regs * regs) |
1da177e4 | 486 | { |
7d12e780 | 487 | struct pt_regs *old_regs; |
7df10275 AB |
488 | u64 *next_tb = &__get_cpu_var(decrementers_next_tb); |
489 | struct clock_event_device *evt = &__get_cpu_var(decrementers); | |
860aed25 | 490 | u64 now; |
d831d0b8 | 491 | |
963e5d3b BH |
492 | /* Ensure a positive value is written to the decrementer, or else |
493 | * some CPUs will continue to take decrementer exceptions. | |
494 | */ | |
495 | set_dec(DECREMENTER_MAX); | |
496 | ||
497 | /* Some implementations of hotplug will get timer interrupts while | |
689dfa89 TC |
498 | * offline, just ignore these and we also need to set |
499 | * decrementers_next_tb as MAX to make sure __check_irq_replay | |
500 | * don't replay timer interrupt when return, otherwise we'll trap | |
501 | * here infinitely :( | |
963e5d3b | 502 | */ |
689dfa89 TC |
503 | if (!cpu_online(smp_processor_id())) { |
504 | *next_tb = ~(u64)0; | |
963e5d3b | 505 | return; |
689dfa89 | 506 | } |
963e5d3b | 507 | |
7230c564 BH |
508 | /* Conditionally hard-enable interrupts now that the DEC has been |
509 | * bumped to its maximum value | |
510 | */ | |
511 | may_hard_irq_enable(); | |
512 | ||
89713ed1 | 513 | |
b0d278b7 | 514 | #if defined(CONFIG_PPC32) && defined(CONFIG_PMAC) |
f2783c15 PM |
515 | if (atomic_read(&ppc_n_lost_interrupts) != 0) |
516 | do_IRQ(regs); | |
517 | #endif | |
1da177e4 | 518 | |
7d12e780 | 519 | old_regs = set_irq_regs(regs); |
1da177e4 LT |
520 | irq_enter(); |
521 | ||
e72bbbab LZ |
522 | trace_timer_interrupt_entry(regs); |
523 | ||
e360adbe PZ |
524 | if (test_irq_work_pending()) { |
525 | clear_irq_work_pending(); | |
526 | irq_work_run(); | |
0fe1ac48 PM |
527 | } |
528 | ||
860aed25 PM |
529 | now = get_tb_or_rtc(); |
530 | if (now >= *next_tb) { | |
531 | *next_tb = ~(u64)0; | |
532 | if (evt->event_handler) | |
533 | evt->event_handler(evt); | |
c041cfa2 | 534 | __get_cpu_var(irq_stat).timer_irqs_event++; |
860aed25 PM |
535 | } else { |
536 | now = *next_tb - now; | |
537 | if (now <= DECREMENTER_MAX) | |
538 | set_dec((int)now); | |
0215f7d8 BH |
539 | /* We may have raced with new irq work */ |
540 | if (test_irq_work_pending()) | |
541 | set_dec(1); | |
c041cfa2 | 542 | __get_cpu_var(irq_stat).timer_irqs_others++; |
860aed25 | 543 | } |
1da177e4 | 544 | |
f2783c15 | 545 | #ifdef CONFIG_PPC64 |
8d15a3e5 | 546 | /* collect purr register values often, for accurate calculations */ |
1ababe11 | 547 | if (firmware_has_feature(FW_FEATURE_SPLPAR)) { |
1da177e4 LT |
548 | struct cpu_usage *cu = &__get_cpu_var(cpu_usage_array); |
549 | cu->current_tb = mfspr(SPRN_PURR); | |
550 | } | |
f2783c15 | 551 | #endif |
1da177e4 | 552 | |
e72bbbab LZ |
553 | trace_timer_interrupt_exit(regs); |
554 | ||
1da177e4 | 555 | irq_exit(); |
7d12e780 | 556 | set_irq_regs(old_regs); |
1da177e4 LT |
557 | } |
558 | ||
dabe859e PM |
559 | /* |
560 | * Hypervisor decrementer interrupts shouldn't occur but are sometimes | |
561 | * left pending on exit from a KVM guest. We don't need to do anything | |
562 | * to clear them, as they are edge-triggered. | |
563 | */ | |
564 | void hdec_interrupt(struct pt_regs *regs) | |
565 | { | |
566 | } | |
567 | ||
7ac5dde9 | 568 | #ifdef CONFIG_SUSPEND |
d75d68cf | 569 | static void generic_suspend_disable_irqs(void) |
7ac5dde9 | 570 | { |
7ac5dde9 SW |
571 | /* Disable the decrementer, so that it doesn't interfere |
572 | * with suspending. | |
573 | */ | |
574 | ||
621692cb | 575 | set_dec(DECREMENTER_MAX); |
7ac5dde9 | 576 | local_irq_disable(); |
621692cb | 577 | set_dec(DECREMENTER_MAX); |
7ac5dde9 SW |
578 | } |
579 | ||
d75d68cf | 580 | static void generic_suspend_enable_irqs(void) |
7ac5dde9 | 581 | { |
7ac5dde9 | 582 | local_irq_enable(); |
7ac5dde9 SW |
583 | } |
584 | ||
585 | /* Overrides the weak version in kernel/power/main.c */ | |
586 | void arch_suspend_disable_irqs(void) | |
587 | { | |
588 | if (ppc_md.suspend_disable_irqs) | |
589 | ppc_md.suspend_disable_irqs(); | |
590 | generic_suspend_disable_irqs(); | |
591 | } | |
592 | ||
593 | /* Overrides the weak version in kernel/power/main.c */ | |
594 | void arch_suspend_enable_irqs(void) | |
595 | { | |
596 | generic_suspend_enable_irqs(); | |
597 | if (ppc_md.suspend_enable_irqs) | |
598 | ppc_md.suspend_enable_irqs(); | |
599 | } | |
600 | #endif | |
601 | ||
1da177e4 LT |
602 | /* |
603 | * Scheduler clock - returns current time in nanosec units. | |
604 | * | |
605 | * Note: mulhdu(a, b) (multiply high double unsigned) returns | |
606 | * the high 64 bits of a * b, i.e. (a * b) >> 64, where a and b | |
607 | * are 64-bit unsigned numbers. | |
608 | */ | |
609 | unsigned long long sched_clock(void) | |
610 | { | |
96c44507 PM |
611 | if (__USE_RTC()) |
612 | return get_rtc(); | |
fc9069fe | 613 | return mulhdu(get_tb() - boot_tb, tb_to_ns_scale) << tb_to_ns_shift; |
1da177e4 LT |
614 | } |
615 | ||
0bb474a4 | 616 | static int __init get_freq(char *name, int cells, unsigned long *val) |
10f7e7c1 AB |
617 | { |
618 | struct device_node *cpu; | |
6f7aba7b | 619 | const __be32 *fp; |
0bb474a4 | 620 | int found = 0; |
10f7e7c1 | 621 | |
0bb474a4 | 622 | /* The cpu node should have timebase and clock frequency properties */ |
10f7e7c1 AB |
623 | cpu = of_find_node_by_type(NULL, "cpu"); |
624 | ||
d8a8188d | 625 | if (cpu) { |
e2eb6392 | 626 | fp = of_get_property(cpu, name, NULL); |
d8a8188d | 627 | if (fp) { |
0bb474a4 | 628 | found = 1; |
a4dc7ff0 | 629 | *val = of_read_ulong(fp, cells); |
10f7e7c1 | 630 | } |
0bb474a4 AB |
631 | |
632 | of_node_put(cpu); | |
10f7e7c1 | 633 | } |
0bb474a4 AB |
634 | |
635 | return found; | |
636 | } | |
637 | ||
77c0a700 BH |
638 | void start_cpu_decrementer(void) |
639 | { | |
640 | #if defined(CONFIG_BOOKE) || defined(CONFIG_40x) | |
641 | /* Clear any pending timer interrupts */ | |
642 | mtspr(SPRN_TSR, TSR_ENW | TSR_WIS | TSR_DIS | TSR_FIS); | |
643 | ||
644 | /* Enable decrementer interrupt */ | |
645 | mtspr(SPRN_TCR, TCR_DIE); | |
646 | #endif /* defined(CONFIG_BOOKE) || defined(CONFIG_40x) */ | |
647 | } | |
648 | ||
0bb474a4 AB |
649 | void __init generic_calibrate_decr(void) |
650 | { | |
651 | ppc_tb_freq = DEFAULT_TB_FREQ; /* hardcoded default */ | |
652 | ||
653 | if (!get_freq("ibm,extended-timebase-frequency", 2, &ppc_tb_freq) && | |
654 | !get_freq("timebase-frequency", 1, &ppc_tb_freq)) { | |
655 | ||
10f7e7c1 AB |
656 | printk(KERN_ERR "WARNING: Estimating decrementer frequency " |
657 | "(not found)\n"); | |
0bb474a4 | 658 | } |
10f7e7c1 | 659 | |
0bb474a4 AB |
660 | ppc_proc_freq = DEFAULT_PROC_FREQ; /* hardcoded default */ |
661 | ||
662 | if (!get_freq("ibm,extended-clock-frequency", 2, &ppc_proc_freq) && | |
663 | !get_freq("clock-frequency", 1, &ppc_proc_freq)) { | |
664 | ||
665 | printk(KERN_ERR "WARNING: Estimating processor frequency " | |
666 | "(not found)\n"); | |
10f7e7c1 | 667 | } |
10f7e7c1 | 668 | } |
10f7e7c1 | 669 | |
aa3be5f3 | 670 | int update_persistent_clock(struct timespec now) |
f2783c15 PM |
671 | { |
672 | struct rtc_time tm; | |
673 | ||
aa3be5f3 | 674 | if (!ppc_md.set_rtc_time) |
023f333a | 675 | return -ENODEV; |
aa3be5f3 TB |
676 | |
677 | to_tm(now.tv_sec + 1 + timezone_offset, &tm); | |
678 | tm.tm_year -= 1900; | |
679 | tm.tm_mon -= 1; | |
680 | ||
681 | return ppc_md.set_rtc_time(&tm); | |
682 | } | |
683 | ||
978d7eb3 | 684 | static void __read_persistent_clock(struct timespec *ts) |
aa3be5f3 TB |
685 | { |
686 | struct rtc_time tm; | |
687 | static int first = 1; | |
688 | ||
d90246cd | 689 | ts->tv_nsec = 0; |
aa3be5f3 TB |
690 | /* XXX this is a litle fragile but will work okay in the short term */ |
691 | if (first) { | |
692 | first = 0; | |
693 | if (ppc_md.time_init) | |
694 | timezone_offset = ppc_md.time_init(); | |
695 | ||
696 | /* get_boot_time() isn't guaranteed to be safe to call late */ | |
d90246cd MS |
697 | if (ppc_md.get_boot_time) { |
698 | ts->tv_sec = ppc_md.get_boot_time() - timezone_offset; | |
699 | return; | |
700 | } | |
701 | } | |
702 | if (!ppc_md.get_rtc_time) { | |
703 | ts->tv_sec = 0; | |
704 | return; | |
aa3be5f3 | 705 | } |
f2783c15 | 706 | ppc_md.get_rtc_time(&tm); |
978d7eb3 | 707 | |
d4f587c6 MS |
708 | ts->tv_sec = mktime(tm.tm_year+1900, tm.tm_mon+1, tm.tm_mday, |
709 | tm.tm_hour, tm.tm_min, tm.tm_sec); | |
f2783c15 PM |
710 | } |
711 | ||
978d7eb3 BH |
712 | void read_persistent_clock(struct timespec *ts) |
713 | { | |
714 | __read_persistent_clock(ts); | |
715 | ||
716 | /* Sanitize it in case real time clock is set below EPOCH */ | |
717 | if (ts->tv_sec < 0) { | |
718 | ts->tv_sec = 0; | |
719 | ts->tv_nsec = 0; | |
720 | } | |
721 | ||
722 | } | |
723 | ||
4a4cfe38 | 724 | /* clocksource code */ |
8e19608e | 725 | static cycle_t rtc_read(struct clocksource *cs) |
4a4cfe38 TB |
726 | { |
727 | return (cycle_t)get_rtc(); | |
728 | } | |
729 | ||
8e19608e | 730 | static cycle_t timebase_read(struct clocksource *cs) |
4a4cfe38 TB |
731 | { |
732 | return (cycle_t)get_tb(); | |
733 | } | |
734 | ||
70639421 | 735 | void update_vsyscall_old(struct timespec *wall_time, struct timespec *wtm, |
7615856e | 736 | struct clocksource *clock, u32 mult) |
4a4cfe38 | 737 | { |
b0797b60 | 738 | u64 new_tb_to_xs, new_stamp_xsec; |
47916be4 | 739 | u32 frac_sec; |
4a4cfe38 TB |
740 | |
741 | if (clock != &clocksource_timebase) | |
742 | return; | |
743 | ||
744 | /* Make userspace gettimeofday spin until we're done. */ | |
745 | ++vdso_data->tb_update_count; | |
746 | smp_mb(); | |
747 | ||
11b8633a AB |
748 | /* 19342813113834067 ~= 2^(20+64) / 1e9 */ |
749 | new_tb_to_xs = (u64) mult * (19342813113834067ULL >> clock->shift); | |
06d518e3 | 750 | new_stamp_xsec = (u64) wall_time->tv_nsec * XSEC_PER_SEC; |
b0797b60 | 751 | do_div(new_stamp_xsec, 1000000000); |
06d518e3 | 752 | new_stamp_xsec += (u64) wall_time->tv_sec * XSEC_PER_SEC; |
b0797b60 | 753 | |
47916be4 TG |
754 | BUG_ON(wall_time->tv_nsec >= NSEC_PER_SEC); |
755 | /* this is tv_nsec / 1e9 as a 0.32 fraction */ | |
756 | frac_sec = ((u64) wall_time->tv_nsec * 18446744073ULL) >> 32; | |
757 | ||
b0797b60 JS |
758 | /* |
759 | * tb_update_count is used to allow the userspace gettimeofday code | |
760 | * to assure itself that it sees a consistent view of the tb_to_xs and | |
761 | * stamp_xsec variables. It reads the tb_update_count, then reads | |
762 | * tb_to_xs and stamp_xsec and then reads tb_update_count again. If | |
763 | * the two values of tb_update_count match and are even then the | |
764 | * tb_to_xs and stamp_xsec values are consistent. If not, then it | |
765 | * loops back and reads them again until this criteria is met. | |
766 | * We expect the caller to have done the first increment of | |
767 | * vdso_data->tb_update_count already. | |
768 | */ | |
769 | vdso_data->tb_orig_stamp = clock->cycle_last; | |
770 | vdso_data->stamp_xsec = new_stamp_xsec; | |
771 | vdso_data->tb_to_xs = new_tb_to_xs; | |
7615856e JS |
772 | vdso_data->wtom_clock_sec = wtm->tv_sec; |
773 | vdso_data->wtom_clock_nsec = wtm->tv_nsec; | |
06d518e3 | 774 | vdso_data->stamp_xtime = *wall_time; |
0e469db8 | 775 | vdso_data->stamp_sec_fraction = frac_sec; |
b0797b60 JS |
776 | smp_wmb(); |
777 | ++(vdso_data->tb_update_count); | |
4a4cfe38 TB |
778 | } |
779 | ||
780 | void update_vsyscall_tz(void) | |
781 | { | |
4a4cfe38 TB |
782 | vdso_data->tz_minuteswest = sys_tz.tz_minuteswest; |
783 | vdso_data->tz_dsttime = sys_tz.tz_dsttime; | |
4a4cfe38 TB |
784 | } |
785 | ||
1c21a293 | 786 | static void __init clocksource_init(void) |
4a4cfe38 TB |
787 | { |
788 | struct clocksource *clock; | |
789 | ||
790 | if (__USE_RTC()) | |
791 | clock = &clocksource_rtc; | |
792 | else | |
793 | clock = &clocksource_timebase; | |
794 | ||
11b8633a | 795 | if (clocksource_register_hz(clock, tb_ticks_per_sec)) { |
4a4cfe38 TB |
796 | printk(KERN_ERR "clocksource: %s is already registered\n", |
797 | clock->name); | |
798 | return; | |
799 | } | |
800 | ||
801 | printk(KERN_INFO "clocksource: %s mult[%x] shift[%d] registered\n", | |
802 | clock->name, clock->mult, clock->shift); | |
803 | } | |
804 | ||
d831d0b8 TB |
805 | static int decrementer_set_next_event(unsigned long evt, |
806 | struct clock_event_device *dev) | |
807 | { | |
0215f7d8 BH |
808 | /* Don't adjust the decrementer if some irq work is pending */ |
809 | if (test_irq_work_pending()) | |
810 | return 0; | |
7df10275 | 811 | __get_cpu_var(decrementers_next_tb) = get_tb_or_rtc() + evt; |
d831d0b8 | 812 | set_dec(evt); |
0215f7d8 BH |
813 | |
814 | /* We may have raced with new irq work */ | |
815 | if (test_irq_work_pending()) | |
816 | set_dec(1); | |
817 | ||
d831d0b8 TB |
818 | return 0; |
819 | } | |
820 | ||
821 | static void decrementer_set_mode(enum clock_event_mode mode, | |
822 | struct clock_event_device *dev) | |
823 | { | |
824 | if (mode != CLOCK_EVT_MODE_ONESHOT) | |
825 | decrementer_set_next_event(DECREMENTER_MAX, dev); | |
826 | } | |
827 | ||
828 | static void register_decrementer_clockevent(int cpu) | |
829 | { | |
7df10275 | 830 | struct clock_event_device *dec = &per_cpu(decrementers, cpu); |
d831d0b8 TB |
831 | |
832 | *dec = decrementer_clockevent; | |
320ab2b0 | 833 | dec->cpumask = cpumask_of(cpu); |
d831d0b8 | 834 | |
b919ee82 AB |
835 | printk_once(KERN_DEBUG "clockevent: %s mult[%x] shift[%d] cpu[%d]\n", |
836 | dec->name, dec->mult, dec->shift, cpu); | |
d831d0b8 TB |
837 | |
838 | clockevents_register_device(dec); | |
839 | } | |
840 | ||
c481887f | 841 | static void __init init_decrementer_clockevent(void) |
d831d0b8 TB |
842 | { |
843 | int cpu = smp_processor_id(); | |
844 | ||
d8afc6fd AB |
845 | clockevents_calc_mult_shift(&decrementer_clockevent, ppc_tb_freq, 4); |
846 | ||
d831d0b8 TB |
847 | decrementer_clockevent.max_delta_ns = |
848 | clockevent_delta2ns(DECREMENTER_MAX, &decrementer_clockevent); | |
43875cc0 PM |
849 | decrementer_clockevent.min_delta_ns = |
850 | clockevent_delta2ns(2, &decrementer_clockevent); | |
d831d0b8 TB |
851 | |
852 | register_decrementer_clockevent(cpu); | |
853 | } | |
854 | ||
855 | void secondary_cpu_time_init(void) | |
856 | { | |
77c0a700 BH |
857 | /* Start the decrementer on CPUs that have manual control |
858 | * such as BookE | |
859 | */ | |
860 | start_cpu_decrementer(); | |
861 | ||
d831d0b8 TB |
862 | /* FIME: Should make unrelatred change to move snapshot_timebase |
863 | * call here ! */ | |
864 | register_decrementer_clockevent(smp_processor_id()); | |
865 | } | |
866 | ||
f2783c15 | 867 | /* This function is only called on the boot processor */ |
1da177e4 LT |
868 | void __init time_init(void) |
869 | { | |
1da177e4 | 870 | struct div_result res; |
d75d68cf | 871 | u64 scale; |
f2783c15 PM |
872 | unsigned shift; |
873 | ||
96c44507 PM |
874 | if (__USE_RTC()) { |
875 | /* 601 processor: dec counts down by 128 every 128ns */ | |
876 | ppc_tb_freq = 1000000000; | |
96c44507 PM |
877 | } else { |
878 | /* Normal PowerPC with timebase register */ | |
879 | ppc_md.calibrate_decr(); | |
224ad80a | 880 | printk(KERN_DEBUG "time_init: decrementer frequency = %lu.%.6lu MHz\n", |
96c44507 | 881 | ppc_tb_freq / 1000000, ppc_tb_freq % 1000000); |
224ad80a | 882 | printk(KERN_DEBUG "time_init: processor frequency = %lu.%.6lu MHz\n", |
96c44507 | 883 | ppc_proc_freq / 1000000, ppc_proc_freq % 1000000); |
96c44507 | 884 | } |
374e99d4 PM |
885 | |
886 | tb_ticks_per_jiffy = ppc_tb_freq / HZ; | |
092b8f34 | 887 | tb_ticks_per_sec = ppc_tb_freq; |
374e99d4 | 888 | tb_ticks_per_usec = ppc_tb_freq / 1000000; |
c6622f63 | 889 | calc_cputime_factors(); |
a42548a1 | 890 | setup_cputime_one_jiffy(); |
092b8f34 | 891 | |
1da177e4 LT |
892 | /* |
893 | * Compute scale factor for sched_clock. | |
894 | * The calibrate_decr() function has set tb_ticks_per_sec, | |
895 | * which is the timebase frequency. | |
896 | * We compute 1e9 * 2^64 / tb_ticks_per_sec and interpret | |
897 | * the 128-bit result as a 64.64 fixed-point number. | |
898 | * We then shift that number right until it is less than 1.0, | |
899 | * giving us the scale factor and shift count to use in | |
900 | * sched_clock(). | |
901 | */ | |
902 | div128_by_32(1000000000, 0, tb_ticks_per_sec, &res); | |
903 | scale = res.result_low; | |
904 | for (shift = 0; res.result_high != 0; ++shift) { | |
905 | scale = (scale >> 1) | (res.result_high << 63); | |
906 | res.result_high >>= 1; | |
907 | } | |
908 | tb_to_ns_scale = scale; | |
909 | tb_to_ns_shift = shift; | |
fc9069fe | 910 | /* Save the current timebase to pretty up CONFIG_PRINTK_TIME */ |
c27da339 | 911 | boot_tb = get_tb_or_rtc(); |
1da177e4 | 912 | |
092b8f34 | 913 | /* If platform provided a timezone (pmac), we correct the time */ |
621692cb | 914 | if (timezone_offset) { |
092b8f34 PM |
915 | sys_tz.tz_minuteswest = -timezone_offset / 60; |
916 | sys_tz.tz_dsttime = 0; | |
621692cb | 917 | } |
092b8f34 | 918 | |
a7f290da BH |
919 | vdso_data->tb_update_count = 0; |
920 | vdso_data->tb_ticks_per_sec = tb_ticks_per_sec; | |
1da177e4 | 921 | |
77c0a700 BH |
922 | /* Start the decrementer on CPUs that have manual control |
923 | * such as BookE | |
924 | */ | |
925 | start_cpu_decrementer(); | |
926 | ||
f5339277 SR |
927 | /* Register the clocksource */ |
928 | clocksource_init(); | |
4a4cfe38 | 929 | |
d831d0b8 | 930 | init_decrementer_clockevent(); |
1da177e4 LT |
931 | } |
932 | ||
1da177e4 | 933 | |
1da177e4 LT |
934 | #define FEBRUARY 2 |
935 | #define STARTOFTIME 1970 | |
936 | #define SECDAY 86400L | |
937 | #define SECYR (SECDAY * 365) | |
f2783c15 PM |
938 | #define leapyear(year) ((year) % 4 == 0 && \ |
939 | ((year) % 100 != 0 || (year) % 400 == 0)) | |
1da177e4 LT |
940 | #define days_in_year(a) (leapyear(a) ? 366 : 365) |
941 | #define days_in_month(a) (month_days[(a) - 1]) | |
942 | ||
943 | static int month_days[12] = { | |
944 | 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 | |
945 | }; | |
946 | ||
947 | /* | |
948 | * This only works for the Gregorian calendar - i.e. after 1752 (in the UK) | |
949 | */ | |
950 | void GregorianDay(struct rtc_time * tm) | |
951 | { | |
952 | int leapsToDate; | |
953 | int lastYear; | |
954 | int day; | |
955 | int MonthOffset[] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 }; | |
956 | ||
f2783c15 | 957 | lastYear = tm->tm_year - 1; |
1da177e4 LT |
958 | |
959 | /* | |
960 | * Number of leap corrections to apply up to end of last year | |
961 | */ | |
f2783c15 | 962 | leapsToDate = lastYear / 4 - lastYear / 100 + lastYear / 400; |
1da177e4 LT |
963 | |
964 | /* | |
965 | * This year is a leap year if it is divisible by 4 except when it is | |
966 | * divisible by 100 unless it is divisible by 400 | |
967 | * | |
f2783c15 | 968 | * e.g. 1904 was a leap year, 1900 was not, 1996 is, and 2000 was |
1da177e4 | 969 | */ |
f2783c15 | 970 | day = tm->tm_mon > 2 && leapyear(tm->tm_year); |
1da177e4 LT |
971 | |
972 | day += lastYear*365 + leapsToDate + MonthOffset[tm->tm_mon-1] + | |
973 | tm->tm_mday; | |
974 | ||
f2783c15 | 975 | tm->tm_wday = day % 7; |
1da177e4 LT |
976 | } |
977 | ||
978 | void to_tm(int tim, struct rtc_time * tm) | |
979 | { | |
980 | register int i; | |
981 | register long hms, day; | |
982 | ||
983 | day = tim / SECDAY; | |
984 | hms = tim % SECDAY; | |
985 | ||
986 | /* Hours, minutes, seconds are easy */ | |
987 | tm->tm_hour = hms / 3600; | |
988 | tm->tm_min = (hms % 3600) / 60; | |
989 | tm->tm_sec = (hms % 3600) % 60; | |
990 | ||
991 | /* Number of years in days */ | |
992 | for (i = STARTOFTIME; day >= days_in_year(i); i++) | |
993 | day -= days_in_year(i); | |
994 | tm->tm_year = i; | |
995 | ||
996 | /* Number of months in days left */ | |
997 | if (leapyear(tm->tm_year)) | |
998 | days_in_month(FEBRUARY) = 29; | |
999 | for (i = 1; day >= days_in_month(i); i++) | |
1000 | day -= days_in_month(i); | |
1001 | days_in_month(FEBRUARY) = 28; | |
1002 | tm->tm_mon = i; | |
1003 | ||
1004 | /* Days are what is left over (+1) from all that. */ | |
1005 | tm->tm_mday = day + 1; | |
1006 | ||
1007 | /* | |
1008 | * Determine the day of week | |
1009 | */ | |
1010 | GregorianDay(tm); | |
1011 | } | |
1012 | ||
1da177e4 LT |
1013 | /* |
1014 | * Divide a 128-bit dividend by a 32-bit divisor, leaving a 128 bit | |
1015 | * result. | |
1016 | */ | |
f2783c15 PM |
1017 | void div128_by_32(u64 dividend_high, u64 dividend_low, |
1018 | unsigned divisor, struct div_result *dr) | |
1da177e4 | 1019 | { |
f2783c15 PM |
1020 | unsigned long a, b, c, d; |
1021 | unsigned long w, x, y, z; | |
1022 | u64 ra, rb, rc; | |
1da177e4 LT |
1023 | |
1024 | a = dividend_high >> 32; | |
1025 | b = dividend_high & 0xffffffff; | |
1026 | c = dividend_low >> 32; | |
1027 | d = dividend_low & 0xffffffff; | |
1028 | ||
f2783c15 PM |
1029 | w = a / divisor; |
1030 | ra = ((u64)(a - (w * divisor)) << 32) + b; | |
1031 | ||
f2783c15 PM |
1032 | rb = ((u64) do_div(ra, divisor) << 32) + c; |
1033 | x = ra; | |
1da177e4 | 1034 | |
f2783c15 PM |
1035 | rc = ((u64) do_div(rb, divisor) << 32) + d; |
1036 | y = rb; | |
1037 | ||
1038 | do_div(rc, divisor); | |
1039 | z = rc; | |
1da177e4 | 1040 | |
f2783c15 PM |
1041 | dr->result_high = ((u64)w << 32) + x; |
1042 | dr->result_low = ((u64)y << 32) + z; | |
1da177e4 LT |
1043 | |
1044 | } | |
bcd68a70 | 1045 | |
177996e6 BH |
1046 | /* We don't need to calibrate delay, we use the CPU timebase for that */ |
1047 | void calibrate_delay(void) | |
1048 | { | |
1049 | /* Some generic code (such as spinlock debug) use loops_per_jiffy | |
1050 | * as the number of __delay(1) in a jiffy, so make it so | |
1051 | */ | |
1052 | loops_per_jiffy = tb_ticks_per_jiffy; | |
1053 | } | |
1054 | ||
bcd68a70 GU |
1055 | static int __init rtc_init(void) |
1056 | { | |
1057 | struct platform_device *pdev; | |
1058 | ||
1059 | if (!ppc_md.get_rtc_time) | |
1060 | return -ENODEV; | |
1061 | ||
1062 | pdev = platform_device_register_simple("rtc-generic", -1, NULL, 0); | |
bcd68a70 | 1063 | |
8c6ffba0 | 1064 | return PTR_ERR_OR_ZERO(pdev); |
bcd68a70 GU |
1065 | } |
1066 | ||
1067 | module_init(rtc_init); |