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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 | 44 | #include <linux/time.h> |
0d948730 | 45 | #include <linux/clockchips.h> |
1da177e4 LT |
46 | #include <linux/init.h> |
47 | #include <linux/profile.h> | |
48 | #include <linux/cpu.h> | |
49 | #include <linux/security.h> | |
f2783c15 PM |
50 | #include <linux/percpu.h> |
51 | #include <linux/rtc.h> | |
092b8f34 | 52 | #include <linux/jiffies.h> |
c6622f63 | 53 | #include <linux/posix-timers.h> |
7d12e780 | 54 | #include <linux/irq.h> |
177996e6 | 55 | #include <linux/delay.h> |
e360adbe | 56 | #include <linux/irq_work.h> |
f0d37300 | 57 | #include <linux/clk-provider.h> |
6795b85c | 58 | #include <asm/trace.h> |
1da177e4 | 59 | |
1da177e4 LT |
60 | #include <asm/io.h> |
61 | #include <asm/processor.h> | |
62 | #include <asm/nvram.h> | |
63 | #include <asm/cache.h> | |
64 | #include <asm/machdep.h> | |
1da177e4 LT |
65 | #include <asm/uaccess.h> |
66 | #include <asm/time.h> | |
1da177e4 | 67 | #include <asm/prom.h> |
f2783c15 PM |
68 | #include <asm/irq.h> |
69 | #include <asm/div64.h> | |
2249ca9d | 70 | #include <asm/smp.h> |
a7f290da | 71 | #include <asm/vdso_datapage.h> |
1ababe11 | 72 | #include <asm/firmware.h> |
06b8e878 | 73 | #include <asm/cputime.h> |
1da177e4 | 74 | |
4a4cfe38 TB |
75 | /* powerpc clocksource/clockevent code */ |
76 | ||
d831d0b8 | 77 | #include <linux/clockchips.h> |
189374ae | 78 | #include <linux/timekeeper_internal.h> |
4a4cfe38 | 79 | |
8e19608e | 80 | static cycle_t rtc_read(struct clocksource *); |
4a4cfe38 TB |
81 | static struct clocksource clocksource_rtc = { |
82 | .name = "rtc", | |
83 | .rating = 400, | |
84 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | |
85 | .mask = CLOCKSOURCE_MASK(64), | |
4a4cfe38 TB |
86 | .read = rtc_read, |
87 | }; | |
88 | ||
8e19608e | 89 | static cycle_t timebase_read(struct clocksource *); |
4a4cfe38 TB |
90 | static struct clocksource clocksource_timebase = { |
91 | .name = "timebase", | |
92 | .rating = 400, | |
93 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | |
94 | .mask = CLOCKSOURCE_MASK(64), | |
4a4cfe38 TB |
95 | .read = timebase_read, |
96 | }; | |
97 | ||
d831d0b8 TB |
98 | #define DECREMENTER_MAX 0x7fffffff |
99 | ||
100 | static int decrementer_set_next_event(unsigned long evt, | |
101 | struct clock_event_device *dev); | |
37a13e78 | 102 | static int decrementer_shutdown(struct clock_event_device *evt); |
d831d0b8 | 103 | |
6e35994d | 104 | struct clock_event_device decrementer_clockevent = { |
37a13e78 VK |
105 | .name = "decrementer", |
106 | .rating = 200, | |
107 | .irq = 0, | |
108 | .set_next_event = decrementer_set_next_event, | |
109 | .set_state_shutdown = decrementer_shutdown, | |
110 | .tick_resume = decrementer_shutdown, | |
111 | .features = CLOCK_EVT_FEAT_ONESHOT | | |
112 | CLOCK_EVT_FEAT_C3STOP, | |
d831d0b8 | 113 | }; |
6e35994d | 114 | EXPORT_SYMBOL(decrementer_clockevent); |
d831d0b8 | 115 | |
7df10275 AB |
116 | DEFINE_PER_CPU(u64, decrementers_next_tb); |
117 | static DEFINE_PER_CPU(struct clock_event_device, decrementers); | |
d831d0b8 | 118 | |
1da177e4 LT |
119 | #define XSEC_PER_SEC (1024*1024) |
120 | ||
f2783c15 PM |
121 | #ifdef CONFIG_PPC64 |
122 | #define SCALE_XSEC(xsec, max) (((xsec) * max) / XSEC_PER_SEC) | |
123 | #else | |
124 | /* compute ((xsec << 12) * max) >> 32 */ | |
125 | #define SCALE_XSEC(xsec, max) mulhwu((xsec) << 12, max) | |
126 | #endif | |
127 | ||
1da177e4 LT |
128 | unsigned long tb_ticks_per_jiffy; |
129 | unsigned long tb_ticks_per_usec = 100; /* sane default */ | |
130 | EXPORT_SYMBOL(tb_ticks_per_usec); | |
131 | unsigned long tb_ticks_per_sec; | |
2cf82c02 | 132 | EXPORT_SYMBOL(tb_ticks_per_sec); /* for cputime_t conversions */ |
092b8f34 | 133 | |
1da177e4 | 134 | DEFINE_SPINLOCK(rtc_lock); |
6ae3db11 | 135 | EXPORT_SYMBOL_GPL(rtc_lock); |
1da177e4 | 136 | |
fc9069fe TB |
137 | static u64 tb_to_ns_scale __read_mostly; |
138 | static unsigned tb_to_ns_shift __read_mostly; | |
364a1246 | 139 | static u64 boot_tb __read_mostly; |
1da177e4 | 140 | |
1da177e4 | 141 | extern struct timezone sys_tz; |
f2783c15 | 142 | static long timezone_offset; |
1da177e4 | 143 | |
10f7e7c1 | 144 | unsigned long ppc_proc_freq; |
55ec2fca | 145 | EXPORT_SYMBOL_GPL(ppc_proc_freq); |
10f7e7c1 | 146 | unsigned long ppc_tb_freq; |
55ec2fca | 147 | EXPORT_SYMBOL_GPL(ppc_tb_freq); |
96c44507 | 148 | |
abf917cd | 149 | #ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE |
c6622f63 PM |
150 | /* |
151 | * Factors for converting from cputime_t (timebase ticks) to | |
9f5072d4 | 152 | * jiffies, microseconds, seconds, and clock_t (1/USER_HZ seconds). |
c6622f63 PM |
153 | * These are all stored as 0.64 fixed-point binary fractions. |
154 | */ | |
155 | u64 __cputime_jiffies_factor; | |
2cf82c02 | 156 | EXPORT_SYMBOL(__cputime_jiffies_factor); |
9f5072d4 AS |
157 | u64 __cputime_usec_factor; |
158 | EXPORT_SYMBOL(__cputime_usec_factor); | |
c6622f63 | 159 | u64 __cputime_sec_factor; |
2cf82c02 | 160 | EXPORT_SYMBOL(__cputime_sec_factor); |
c6622f63 | 161 | u64 __cputime_clockt_factor; |
2cf82c02 | 162 | EXPORT_SYMBOL(__cputime_clockt_factor); |
06b8e878 MN |
163 | DEFINE_PER_CPU(unsigned long, cputime_last_delta); |
164 | DEFINE_PER_CPU(unsigned long, cputime_scaled_last_delta); | |
c6622f63 | 165 | |
a42548a1 SG |
166 | cputime_t cputime_one_jiffy; |
167 | ||
872e439a PM |
168 | void (*dtl_consumer)(struct dtl_entry *, u64); |
169 | ||
c6622f63 PM |
170 | static void calc_cputime_factors(void) |
171 | { | |
172 | struct div_result res; | |
173 | ||
174 | div128_by_32(HZ, 0, tb_ticks_per_sec, &res); | |
175 | __cputime_jiffies_factor = res.result_low; | |
9f5072d4 AS |
176 | div128_by_32(1000000, 0, tb_ticks_per_sec, &res); |
177 | __cputime_usec_factor = res.result_low; | |
c6622f63 PM |
178 | div128_by_32(1, 0, tb_ticks_per_sec, &res); |
179 | __cputime_sec_factor = res.result_low; | |
180 | div128_by_32(USER_HZ, 0, tb_ticks_per_sec, &res); | |
181 | __cputime_clockt_factor = res.result_low; | |
182 | } | |
183 | ||
184 | /* | |
cf9efce0 PM |
185 | * Read the SPURR on systems that have it, otherwise the PURR, |
186 | * or if that doesn't exist return the timebase value passed in. | |
c6622f63 | 187 | */ |
cf9efce0 | 188 | static u64 read_spurr(u64 tb) |
c6622f63 | 189 | { |
cf9efce0 PM |
190 | if (cpu_has_feature(CPU_FTR_SPURR)) |
191 | return mfspr(SPRN_SPURR); | |
c6622f63 PM |
192 | if (cpu_has_feature(CPU_FTR_PURR)) |
193 | return mfspr(SPRN_PURR); | |
cf9efce0 | 194 | return tb; |
c6622f63 PM |
195 | } |
196 | ||
cf9efce0 PM |
197 | #ifdef CONFIG_PPC_SPLPAR |
198 | ||
4603ac18 | 199 | /* |
cf9efce0 PM |
200 | * Scan the dispatch trace log and count up the stolen time. |
201 | * Should be called with interrupts disabled. | |
4603ac18 | 202 | */ |
cf9efce0 | 203 | static u64 scan_dispatch_log(u64 stop_tb) |
4603ac18 | 204 | { |
872e439a | 205 | u64 i = local_paca->dtl_ridx; |
cf9efce0 PM |
206 | struct dtl_entry *dtl = local_paca->dtl_curr; |
207 | struct dtl_entry *dtl_end = local_paca->dispatch_log_end; | |
208 | struct lppaca *vpa = local_paca->lppaca_ptr; | |
209 | u64 tb_delta; | |
210 | u64 stolen = 0; | |
211 | u64 dtb; | |
212 | ||
84ffae55 AB |
213 | if (!dtl) |
214 | return 0; | |
215 | ||
7ffcf8ec | 216 | if (i == be64_to_cpu(vpa->dtl_idx)) |
cf9efce0 | 217 | return 0; |
7ffcf8ec | 218 | while (i < be64_to_cpu(vpa->dtl_idx)) { |
7ffcf8ec AB |
219 | dtb = be64_to_cpu(dtl->timebase); |
220 | tb_delta = be32_to_cpu(dtl->enqueue_to_dispatch_time) + | |
221 | be32_to_cpu(dtl->ready_to_enqueue_time); | |
cf9efce0 | 222 | barrier(); |
7ffcf8ec | 223 | if (i + N_DISPATCH_LOG < be64_to_cpu(vpa->dtl_idx)) { |
cf9efce0 | 224 | /* buffer has overflowed */ |
7ffcf8ec | 225 | i = be64_to_cpu(vpa->dtl_idx) - N_DISPATCH_LOG; |
cf9efce0 PM |
226 | dtl = local_paca->dispatch_log + (i % N_DISPATCH_LOG); |
227 | continue; | |
228 | } | |
229 | if (dtb > stop_tb) | |
230 | break; | |
84b07386 AB |
231 | if (dtl_consumer) |
232 | dtl_consumer(dtl, i); | |
cf9efce0 PM |
233 | stolen += tb_delta; |
234 | ++i; | |
235 | ++dtl; | |
236 | if (dtl == dtl_end) | |
237 | dtl = local_paca->dispatch_log; | |
238 | } | |
239 | local_paca->dtl_ridx = i; | |
240 | local_paca->dtl_curr = dtl; | |
241 | return stolen; | |
4603ac18 MN |
242 | } |
243 | ||
cf9efce0 PM |
244 | /* |
245 | * Accumulate stolen time by scanning the dispatch trace log. | |
246 | * Called on entry from user mode. | |
247 | */ | |
248 | void accumulate_stolen_time(void) | |
249 | { | |
250 | u64 sst, ust; | |
251 | ||
b18ae08d | 252 | u8 save_soft_enabled = local_paca->soft_enabled; |
b18ae08d TH |
253 | |
254 | /* We are called early in the exception entry, before | |
255 | * soft/hard_enabled are sync'ed to the expected state | |
256 | * for the exception. We are hard disabled but the PACA | |
257 | * needs to reflect that so various debug stuff doesn't | |
258 | * complain | |
259 | */ | |
260 | local_paca->soft_enabled = 0; | |
b18ae08d TH |
261 | |
262 | sst = scan_dispatch_log(local_paca->starttime_user); | |
263 | ust = scan_dispatch_log(local_paca->starttime); | |
264 | local_paca->system_time -= sst; | |
265 | local_paca->user_time -= ust; | |
266 | local_paca->stolen_time += ust + sst; | |
267 | ||
268 | local_paca->soft_enabled = save_soft_enabled; | |
cf9efce0 PM |
269 | } |
270 | ||
271 | static inline u64 calculate_stolen_time(u64 stop_tb) | |
272 | { | |
273 | u64 stolen = 0; | |
274 | ||
7ffcf8ec | 275 | if (get_paca()->dtl_ridx != be64_to_cpu(get_lppaca()->dtl_idx)) { |
cf9efce0 PM |
276 | stolen = scan_dispatch_log(stop_tb); |
277 | get_paca()->system_time -= stolen; | |
278 | } | |
279 | ||
280 | stolen += get_paca()->stolen_time; | |
281 | get_paca()->stolen_time = 0; | |
282 | return stolen; | |
4603ac18 MN |
283 | } |
284 | ||
cf9efce0 PM |
285 | #else /* CONFIG_PPC_SPLPAR */ |
286 | static inline u64 calculate_stolen_time(u64 stop_tb) | |
287 | { | |
288 | return 0; | |
289 | } | |
290 | ||
291 | #endif /* CONFIG_PPC_SPLPAR */ | |
292 | ||
c6622f63 PM |
293 | /* |
294 | * Account time for a transition between system, hard irq | |
295 | * or soft irq state. | |
296 | */ | |
a7e1a9e3 FW |
297 | static u64 vtime_delta(struct task_struct *tsk, |
298 | u64 *sys_scaled, u64 *stolen) | |
c6622f63 | 299 | { |
a7e1a9e3 FW |
300 | u64 now, nowscaled, deltascaled; |
301 | u64 udelta, delta, user_scaled; | |
c6622f63 | 302 | |
1b2852b1 FW |
303 | WARN_ON_ONCE(!irqs_disabled()); |
304 | ||
cf9efce0 | 305 | now = mftb(); |
4603ac18 | 306 | nowscaled = read_spurr(now); |
cf9efce0 PM |
307 | get_paca()->system_time += now - get_paca()->starttime; |
308 | get_paca()->starttime = now; | |
4603ac18 MN |
309 | deltascaled = nowscaled - get_paca()->startspurr; |
310 | get_paca()->startspurr = nowscaled; | |
cf9efce0 | 311 | |
a7e1a9e3 | 312 | *stolen = calculate_stolen_time(now); |
cf9efce0 PM |
313 | |
314 | delta = get_paca()->system_time; | |
315 | get_paca()->system_time = 0; | |
316 | udelta = get_paca()->user_time - get_paca()->utime_sspurr; | |
317 | get_paca()->utime_sspurr = get_paca()->user_time; | |
318 | ||
319 | /* | |
320 | * Because we don't read the SPURR on every kernel entry/exit, | |
321 | * deltascaled includes both user and system SPURR ticks. | |
322 | * Apportion these ticks to system SPURR ticks and user | |
323 | * SPURR ticks in the same ratio as the system time (delta) | |
324 | * and user time (udelta) values obtained from the timebase | |
325 | * over the same interval. The system ticks get accounted here; | |
326 | * the user ticks get saved up in paca->user_time_scaled to be | |
327 | * used by account_process_tick. | |
328 | */ | |
a7e1a9e3 | 329 | *sys_scaled = delta; |
cf9efce0 PM |
330 | user_scaled = udelta; |
331 | if (deltascaled != delta + udelta) { | |
332 | if (udelta) { | |
a7e1a9e3 FW |
333 | *sys_scaled = deltascaled * delta / (delta + udelta); |
334 | user_scaled = deltascaled - *sys_scaled; | |
cf9efce0 | 335 | } else { |
a7e1a9e3 | 336 | *sys_scaled = deltascaled; |
cf9efce0 PM |
337 | } |
338 | } | |
339 | get_paca()->user_time_scaled += user_scaled; | |
340 | ||
a7e1a9e3 FW |
341 | return delta; |
342 | } | |
343 | ||
fd25b4c2 | 344 | void vtime_account_system(struct task_struct *tsk) |
a7e1a9e3 FW |
345 | { |
346 | u64 delta, sys_scaled, stolen; | |
347 | ||
348 | delta = vtime_delta(tsk, &sys_scaled, &stolen); | |
349 | account_system_time(tsk, 0, delta, sys_scaled); | |
350 | if (stolen) | |
351 | account_steal_time(stolen); | |
352 | } | |
c11f11fc | 353 | EXPORT_SYMBOL_GPL(vtime_account_system); |
a7e1a9e3 | 354 | |
fd25b4c2 | 355 | void vtime_account_idle(struct task_struct *tsk) |
a7e1a9e3 FW |
356 | { |
357 | u64 delta, sys_scaled, stolen; | |
358 | ||
359 | delta = vtime_delta(tsk, &sys_scaled, &stolen); | |
360 | account_idle_time(delta + stolen); | |
c6622f63 PM |
361 | } |
362 | ||
363 | /* | |
bcebdf84 FW |
364 | * Transfer the user time accumulated in the paca |
365 | * by the exception entry and exit code to the generic | |
366 | * process user time records. | |
c6622f63 | 367 | * Must be called with interrupts disabled. |
bcebdf84 FW |
368 | * Assumes that vtime_account_system/idle() has been called |
369 | * recently (i.e. since the last entry from usermode) so that | |
cf9efce0 | 370 | * get_paca()->user_time_scaled is up to date. |
c6622f63 | 371 | */ |
bcebdf84 | 372 | void vtime_account_user(struct task_struct *tsk) |
c6622f63 | 373 | { |
4603ac18 | 374 | cputime_t utime, utimescaled; |
c6622f63 PM |
375 | |
376 | utime = get_paca()->user_time; | |
cf9efce0 | 377 | utimescaled = get_paca()->user_time_scaled; |
c6622f63 | 378 | get_paca()->user_time = 0; |
cf9efce0 PM |
379 | get_paca()->user_time_scaled = 0; |
380 | get_paca()->utime_sspurr = 0; | |
457533a7 | 381 | account_user_time(tsk, utime, utimescaled); |
c6622f63 PM |
382 | } |
383 | ||
abf917cd | 384 | #else /* ! CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ |
c6622f63 | 385 | #define calc_cputime_factors() |
c6622f63 PM |
386 | #endif |
387 | ||
6defa38b PM |
388 | void __delay(unsigned long loops) |
389 | { | |
390 | unsigned long start; | |
391 | int diff; | |
392 | ||
393 | if (__USE_RTC()) { | |
394 | start = get_rtcl(); | |
395 | do { | |
396 | /* the RTCL register wraps at 1000000000 */ | |
397 | diff = get_rtcl() - start; | |
398 | if (diff < 0) | |
399 | diff += 1000000000; | |
400 | } while (diff < loops); | |
401 | } else { | |
402 | start = get_tbl(); | |
403 | while (get_tbl() - start < loops) | |
404 | HMT_low(); | |
405 | HMT_medium(); | |
406 | } | |
407 | } | |
408 | EXPORT_SYMBOL(__delay); | |
409 | ||
410 | void udelay(unsigned long usecs) | |
411 | { | |
412 | __delay(tb_ticks_per_usec * usecs); | |
413 | } | |
414 | EXPORT_SYMBOL(udelay); | |
415 | ||
1da177e4 LT |
416 | #ifdef CONFIG_SMP |
417 | unsigned long profile_pc(struct pt_regs *regs) | |
418 | { | |
419 | unsigned long pc = instruction_pointer(regs); | |
420 | ||
421 | if (in_lock_functions(pc)) | |
422 | return regs->link; | |
423 | ||
424 | return pc; | |
425 | } | |
426 | EXPORT_SYMBOL(profile_pc); | |
427 | #endif | |
428 | ||
e360adbe | 429 | #ifdef CONFIG_IRQ_WORK |
105988c0 | 430 | |
0fe1ac48 PM |
431 | /* |
432 | * 64-bit uses a byte in the PACA, 32-bit uses a per-cpu variable... | |
433 | */ | |
434 | #ifdef CONFIG_PPC64 | |
e360adbe | 435 | static inline unsigned long test_irq_work_pending(void) |
105988c0 | 436 | { |
0fe1ac48 PM |
437 | unsigned long x; |
438 | ||
439 | asm volatile("lbz %0,%1(13)" | |
440 | : "=r" (x) | |
e360adbe | 441 | : "i" (offsetof(struct paca_struct, irq_work_pending))); |
0fe1ac48 PM |
442 | return x; |
443 | } | |
444 | ||
e360adbe | 445 | static inline void set_irq_work_pending_flag(void) |
0fe1ac48 PM |
446 | { |
447 | asm volatile("stb %0,%1(13)" : : | |
448 | "r" (1), | |
e360adbe | 449 | "i" (offsetof(struct paca_struct, irq_work_pending))); |
0fe1ac48 PM |
450 | } |
451 | ||
e360adbe | 452 | static inline void clear_irq_work_pending(void) |
0fe1ac48 PM |
453 | { |
454 | asm volatile("stb %0,%1(13)" : : | |
455 | "r" (0), | |
e360adbe | 456 | "i" (offsetof(struct paca_struct, irq_work_pending))); |
105988c0 PM |
457 | } |
458 | ||
0fe1ac48 PM |
459 | #else /* 32-bit */ |
460 | ||
e360adbe | 461 | DEFINE_PER_CPU(u8, irq_work_pending); |
0fe1ac48 | 462 | |
69111bac CL |
463 | #define set_irq_work_pending_flag() __this_cpu_write(irq_work_pending, 1) |
464 | #define test_irq_work_pending() __this_cpu_read(irq_work_pending) | |
465 | #define clear_irq_work_pending() __this_cpu_write(irq_work_pending, 0) | |
105988c0 | 466 | |
0fe1ac48 PM |
467 | #endif /* 32 vs 64 bit */ |
468 | ||
4f8b50bb | 469 | void arch_irq_work_raise(void) |
0fe1ac48 PM |
470 | { |
471 | preempt_disable(); | |
e360adbe | 472 | set_irq_work_pending_flag(); |
0fe1ac48 PM |
473 | set_dec(1); |
474 | preempt_enable(); | |
475 | } | |
476 | ||
e360adbe | 477 | #else /* CONFIG_IRQ_WORK */ |
105988c0 | 478 | |
e360adbe PZ |
479 | #define test_irq_work_pending() 0 |
480 | #define clear_irq_work_pending() | |
105988c0 | 481 | |
e360adbe | 482 | #endif /* CONFIG_IRQ_WORK */ |
105988c0 | 483 | |
e51df2c1 | 484 | static void __timer_interrupt(void) |
1b783955 PM |
485 | { |
486 | struct pt_regs *regs = get_irq_regs(); | |
69111bac CL |
487 | u64 *next_tb = this_cpu_ptr(&decrementers_next_tb); |
488 | struct clock_event_device *evt = this_cpu_ptr(&decrementers); | |
1b783955 PM |
489 | u64 now; |
490 | ||
491 | trace_timer_interrupt_entry(regs); | |
492 | ||
493 | if (test_irq_work_pending()) { | |
494 | clear_irq_work_pending(); | |
495 | irq_work_run(); | |
496 | } | |
497 | ||
498 | now = get_tb_or_rtc(); | |
499 | if (now >= *next_tb) { | |
500 | *next_tb = ~(u64)0; | |
501 | if (evt->event_handler) | |
502 | evt->event_handler(evt); | |
69111bac | 503 | __this_cpu_inc(irq_stat.timer_irqs_event); |
1b783955 PM |
504 | } else { |
505 | now = *next_tb - now; | |
506 | if (now <= DECREMENTER_MAX) | |
507 | set_dec((int)now); | |
508 | /* We may have raced with new irq work */ | |
509 | if (test_irq_work_pending()) | |
510 | set_dec(1); | |
69111bac | 511 | __this_cpu_inc(irq_stat.timer_irqs_others); |
1b783955 PM |
512 | } |
513 | ||
514 | #ifdef CONFIG_PPC64 | |
515 | /* collect purr register values often, for accurate calculations */ | |
516 | if (firmware_has_feature(FW_FEATURE_SPLPAR)) { | |
69111bac | 517 | struct cpu_usage *cu = this_cpu_ptr(&cpu_usage_array); |
1b783955 PM |
518 | cu->current_tb = mfspr(SPRN_PURR); |
519 | } | |
520 | #endif | |
521 | ||
522 | trace_timer_interrupt_exit(regs); | |
523 | } | |
524 | ||
1da177e4 LT |
525 | /* |
526 | * timer_interrupt - gets called when the decrementer overflows, | |
527 | * with interrupts disabled. | |
528 | */ | |
c7aeffc4 | 529 | void timer_interrupt(struct pt_regs * regs) |
1da177e4 | 530 | { |
7d12e780 | 531 | struct pt_regs *old_regs; |
69111bac | 532 | u64 *next_tb = this_cpu_ptr(&decrementers_next_tb); |
d831d0b8 | 533 | |
963e5d3b BH |
534 | /* Ensure a positive value is written to the decrementer, or else |
535 | * some CPUs will continue to take decrementer exceptions. | |
536 | */ | |
537 | set_dec(DECREMENTER_MAX); | |
538 | ||
539 | /* Some implementations of hotplug will get timer interrupts while | |
689dfa89 TC |
540 | * offline, just ignore these and we also need to set |
541 | * decrementers_next_tb as MAX to make sure __check_irq_replay | |
542 | * don't replay timer interrupt when return, otherwise we'll trap | |
543 | * here infinitely :( | |
963e5d3b | 544 | */ |
689dfa89 TC |
545 | if (!cpu_online(smp_processor_id())) { |
546 | *next_tb = ~(u64)0; | |
963e5d3b | 547 | return; |
689dfa89 | 548 | } |
963e5d3b | 549 | |
7230c564 BH |
550 | /* Conditionally hard-enable interrupts now that the DEC has been |
551 | * bumped to its maximum value | |
552 | */ | |
553 | may_hard_irq_enable(); | |
554 | ||
89713ed1 | 555 | |
6e0fdf9a | 556 | #if defined(CONFIG_PPC32) && defined(CONFIG_PPC_PMAC) |
f2783c15 PM |
557 | if (atomic_read(&ppc_n_lost_interrupts) != 0) |
558 | do_IRQ(regs); | |
559 | #endif | |
1da177e4 | 560 | |
7d12e780 | 561 | old_regs = set_irq_regs(regs); |
1da177e4 LT |
562 | irq_enter(); |
563 | ||
1b783955 | 564 | __timer_interrupt(); |
1da177e4 | 565 | irq_exit(); |
7d12e780 | 566 | set_irq_regs(old_regs); |
1da177e4 LT |
567 | } |
568 | ||
dabe859e PM |
569 | /* |
570 | * Hypervisor decrementer interrupts shouldn't occur but are sometimes | |
571 | * left pending on exit from a KVM guest. We don't need to do anything | |
572 | * to clear them, as they are edge-triggered. | |
573 | */ | |
574 | void hdec_interrupt(struct pt_regs *regs) | |
575 | { | |
576 | } | |
577 | ||
7ac5dde9 | 578 | #ifdef CONFIG_SUSPEND |
d75d68cf | 579 | static void generic_suspend_disable_irqs(void) |
7ac5dde9 | 580 | { |
7ac5dde9 SW |
581 | /* Disable the decrementer, so that it doesn't interfere |
582 | * with suspending. | |
583 | */ | |
584 | ||
621692cb | 585 | set_dec(DECREMENTER_MAX); |
7ac5dde9 | 586 | local_irq_disable(); |
621692cb | 587 | set_dec(DECREMENTER_MAX); |
7ac5dde9 SW |
588 | } |
589 | ||
d75d68cf | 590 | static void generic_suspend_enable_irqs(void) |
7ac5dde9 | 591 | { |
7ac5dde9 | 592 | local_irq_enable(); |
7ac5dde9 SW |
593 | } |
594 | ||
595 | /* Overrides the weak version in kernel/power/main.c */ | |
596 | void arch_suspend_disable_irqs(void) | |
597 | { | |
598 | if (ppc_md.suspend_disable_irqs) | |
599 | ppc_md.suspend_disable_irqs(); | |
600 | generic_suspend_disable_irqs(); | |
601 | } | |
602 | ||
603 | /* Overrides the weak version in kernel/power/main.c */ | |
604 | void arch_suspend_enable_irqs(void) | |
605 | { | |
606 | generic_suspend_enable_irqs(); | |
607 | if (ppc_md.suspend_enable_irqs) | |
608 | ppc_md.suspend_enable_irqs(); | |
609 | } | |
610 | #endif | |
611 | ||
b6c295df PM |
612 | unsigned long long tb_to_ns(unsigned long long ticks) |
613 | { | |
614 | return mulhdu(ticks, tb_to_ns_scale) << tb_to_ns_shift; | |
615 | } | |
616 | EXPORT_SYMBOL_GPL(tb_to_ns); | |
617 | ||
1da177e4 LT |
618 | /* |
619 | * Scheduler clock - returns current time in nanosec units. | |
620 | * | |
621 | * Note: mulhdu(a, b) (multiply high double unsigned) returns | |
622 | * the high 64 bits of a * b, i.e. (a * b) >> 64, where a and b | |
623 | * are 64-bit unsigned numbers. | |
624 | */ | |
625 | unsigned long long sched_clock(void) | |
626 | { | |
96c44507 PM |
627 | if (__USE_RTC()) |
628 | return get_rtc(); | |
fc9069fe | 629 | return mulhdu(get_tb() - boot_tb, tb_to_ns_scale) << tb_to_ns_shift; |
1da177e4 LT |
630 | } |
631 | ||
4be1b297 CB |
632 | |
633 | #ifdef CONFIG_PPC_PSERIES | |
634 | ||
635 | /* | |
636 | * Running clock - attempts to give a view of time passing for a virtualised | |
637 | * kernels. | |
638 | * Uses the VTB register if available otherwise a next best guess. | |
639 | */ | |
640 | unsigned long long running_clock(void) | |
641 | { | |
642 | /* | |
643 | * Don't read the VTB as a host since KVM does not switch in host | |
644 | * timebase into the VTB when it takes a guest off the CPU, reading the | |
645 | * VTB would result in reading 'last switched out' guest VTB. | |
646 | * | |
647 | * Host kernels are often compiled with CONFIG_PPC_PSERIES checked, it | |
648 | * would be unsafe to rely only on the #ifdef above. | |
649 | */ | |
650 | if (firmware_has_feature(FW_FEATURE_LPAR) && | |
651 | cpu_has_feature(CPU_FTR_ARCH_207S)) | |
652 | return mulhdu(get_vtb() - boot_tb, tb_to_ns_scale) << tb_to_ns_shift; | |
653 | ||
654 | /* | |
655 | * This is a next best approximation without a VTB. | |
656 | * On a host which is running bare metal there should never be any stolen | |
657 | * time and on a host which doesn't do any virtualisation TB *should* equal | |
658 | * VTB so it makes no difference anyway. | |
659 | */ | |
660 | return local_clock() - cputime_to_nsecs(kcpustat_this_cpu->cpustat[CPUTIME_STEAL]); | |
661 | } | |
662 | #endif | |
663 | ||
0bb474a4 | 664 | static int __init get_freq(char *name, int cells, unsigned long *val) |
10f7e7c1 AB |
665 | { |
666 | struct device_node *cpu; | |
6f7aba7b | 667 | const __be32 *fp; |
0bb474a4 | 668 | int found = 0; |
10f7e7c1 | 669 | |
0bb474a4 | 670 | /* The cpu node should have timebase and clock frequency properties */ |
10f7e7c1 AB |
671 | cpu = of_find_node_by_type(NULL, "cpu"); |
672 | ||
d8a8188d | 673 | if (cpu) { |
e2eb6392 | 674 | fp = of_get_property(cpu, name, NULL); |
d8a8188d | 675 | if (fp) { |
0bb474a4 | 676 | found = 1; |
a4dc7ff0 | 677 | *val = of_read_ulong(fp, cells); |
10f7e7c1 | 678 | } |
0bb474a4 AB |
679 | |
680 | of_node_put(cpu); | |
10f7e7c1 | 681 | } |
0bb474a4 AB |
682 | |
683 | return found; | |
684 | } | |
685 | ||
e51df2c1 | 686 | static void start_cpu_decrementer(void) |
77c0a700 BH |
687 | { |
688 | #if defined(CONFIG_BOOKE) || defined(CONFIG_40x) | |
689 | /* Clear any pending timer interrupts */ | |
690 | mtspr(SPRN_TSR, TSR_ENW | TSR_WIS | TSR_DIS | TSR_FIS); | |
691 | ||
692 | /* Enable decrementer interrupt */ | |
693 | mtspr(SPRN_TCR, TCR_DIE); | |
694 | #endif /* defined(CONFIG_BOOKE) || defined(CONFIG_40x) */ | |
695 | } | |
696 | ||
0bb474a4 AB |
697 | void __init generic_calibrate_decr(void) |
698 | { | |
699 | ppc_tb_freq = DEFAULT_TB_FREQ; /* hardcoded default */ | |
700 | ||
701 | if (!get_freq("ibm,extended-timebase-frequency", 2, &ppc_tb_freq) && | |
702 | !get_freq("timebase-frequency", 1, &ppc_tb_freq)) { | |
703 | ||
10f7e7c1 AB |
704 | printk(KERN_ERR "WARNING: Estimating decrementer frequency " |
705 | "(not found)\n"); | |
0bb474a4 | 706 | } |
10f7e7c1 | 707 | |
0bb474a4 AB |
708 | ppc_proc_freq = DEFAULT_PROC_FREQ; /* hardcoded default */ |
709 | ||
710 | if (!get_freq("ibm,extended-clock-frequency", 2, &ppc_proc_freq) && | |
711 | !get_freq("clock-frequency", 1, &ppc_proc_freq)) { | |
712 | ||
713 | printk(KERN_ERR "WARNING: Estimating processor frequency " | |
714 | "(not found)\n"); | |
10f7e7c1 | 715 | } |
10f7e7c1 | 716 | } |
10f7e7c1 | 717 | |
aa3be5f3 | 718 | int update_persistent_clock(struct timespec now) |
f2783c15 PM |
719 | { |
720 | struct rtc_time tm; | |
721 | ||
aa3be5f3 | 722 | if (!ppc_md.set_rtc_time) |
023f333a | 723 | return -ENODEV; |
aa3be5f3 TB |
724 | |
725 | to_tm(now.tv_sec + 1 + timezone_offset, &tm); | |
726 | tm.tm_year -= 1900; | |
727 | tm.tm_mon -= 1; | |
728 | ||
729 | return ppc_md.set_rtc_time(&tm); | |
730 | } | |
731 | ||
978d7eb3 | 732 | static void __read_persistent_clock(struct timespec *ts) |
aa3be5f3 TB |
733 | { |
734 | struct rtc_time tm; | |
735 | static int first = 1; | |
736 | ||
d90246cd | 737 | ts->tv_nsec = 0; |
aa3be5f3 TB |
738 | /* XXX this is a litle fragile but will work okay in the short term */ |
739 | if (first) { | |
740 | first = 0; | |
741 | if (ppc_md.time_init) | |
742 | timezone_offset = ppc_md.time_init(); | |
743 | ||
744 | /* get_boot_time() isn't guaranteed to be safe to call late */ | |
d90246cd MS |
745 | if (ppc_md.get_boot_time) { |
746 | ts->tv_sec = ppc_md.get_boot_time() - timezone_offset; | |
747 | return; | |
748 | } | |
749 | } | |
750 | if (!ppc_md.get_rtc_time) { | |
751 | ts->tv_sec = 0; | |
752 | return; | |
aa3be5f3 | 753 | } |
f2783c15 | 754 | ppc_md.get_rtc_time(&tm); |
978d7eb3 | 755 | |
d4f587c6 MS |
756 | ts->tv_sec = mktime(tm.tm_year+1900, tm.tm_mon+1, tm.tm_mday, |
757 | tm.tm_hour, tm.tm_min, tm.tm_sec); | |
f2783c15 PM |
758 | } |
759 | ||
978d7eb3 BH |
760 | void read_persistent_clock(struct timespec *ts) |
761 | { | |
762 | __read_persistent_clock(ts); | |
763 | ||
764 | /* Sanitize it in case real time clock is set below EPOCH */ | |
765 | if (ts->tv_sec < 0) { | |
766 | ts->tv_sec = 0; | |
767 | ts->tv_nsec = 0; | |
768 | } | |
769 | ||
770 | } | |
771 | ||
4a4cfe38 | 772 | /* clocksource code */ |
8e19608e | 773 | static cycle_t rtc_read(struct clocksource *cs) |
4a4cfe38 TB |
774 | { |
775 | return (cycle_t)get_rtc(); | |
776 | } | |
777 | ||
8e19608e | 778 | static cycle_t timebase_read(struct clocksource *cs) |
4a4cfe38 TB |
779 | { |
780 | return (cycle_t)get_tb(); | |
781 | } | |
782 | ||
70639421 | 783 | void update_vsyscall_old(struct timespec *wall_time, struct timespec *wtm, |
4a0e6377 | 784 | struct clocksource *clock, u32 mult, cycle_t cycle_last) |
4a4cfe38 | 785 | { |
b0797b60 | 786 | u64 new_tb_to_xs, new_stamp_xsec; |
47916be4 | 787 | u32 frac_sec; |
4a4cfe38 TB |
788 | |
789 | if (clock != &clocksource_timebase) | |
790 | return; | |
791 | ||
792 | /* Make userspace gettimeofday spin until we're done. */ | |
793 | ++vdso_data->tb_update_count; | |
794 | smp_mb(); | |
795 | ||
11b8633a AB |
796 | /* 19342813113834067 ~= 2^(20+64) / 1e9 */ |
797 | new_tb_to_xs = (u64) mult * (19342813113834067ULL >> clock->shift); | |
06d518e3 | 798 | new_stamp_xsec = (u64) wall_time->tv_nsec * XSEC_PER_SEC; |
b0797b60 | 799 | do_div(new_stamp_xsec, 1000000000); |
06d518e3 | 800 | new_stamp_xsec += (u64) wall_time->tv_sec * XSEC_PER_SEC; |
b0797b60 | 801 | |
47916be4 TG |
802 | BUG_ON(wall_time->tv_nsec >= NSEC_PER_SEC); |
803 | /* this is tv_nsec / 1e9 as a 0.32 fraction */ | |
804 | frac_sec = ((u64) wall_time->tv_nsec * 18446744073ULL) >> 32; | |
805 | ||
b0797b60 JS |
806 | /* |
807 | * tb_update_count is used to allow the userspace gettimeofday code | |
808 | * to assure itself that it sees a consistent view of the tb_to_xs and | |
809 | * stamp_xsec variables. It reads the tb_update_count, then reads | |
810 | * tb_to_xs and stamp_xsec and then reads tb_update_count again. If | |
811 | * the two values of tb_update_count match and are even then the | |
812 | * tb_to_xs and stamp_xsec values are consistent. If not, then it | |
813 | * loops back and reads them again until this criteria is met. | |
814 | * We expect the caller to have done the first increment of | |
815 | * vdso_data->tb_update_count already. | |
816 | */ | |
4a0e6377 | 817 | vdso_data->tb_orig_stamp = cycle_last; |
b0797b60 JS |
818 | vdso_data->stamp_xsec = new_stamp_xsec; |
819 | vdso_data->tb_to_xs = new_tb_to_xs; | |
7615856e JS |
820 | vdso_data->wtom_clock_sec = wtm->tv_sec; |
821 | vdso_data->wtom_clock_nsec = wtm->tv_nsec; | |
06d518e3 | 822 | vdso_data->stamp_xtime = *wall_time; |
0e469db8 | 823 | vdso_data->stamp_sec_fraction = frac_sec; |
b0797b60 JS |
824 | smp_wmb(); |
825 | ++(vdso_data->tb_update_count); | |
4a4cfe38 TB |
826 | } |
827 | ||
828 | void update_vsyscall_tz(void) | |
829 | { | |
4a4cfe38 TB |
830 | vdso_data->tz_minuteswest = sys_tz.tz_minuteswest; |
831 | vdso_data->tz_dsttime = sys_tz.tz_dsttime; | |
4a4cfe38 TB |
832 | } |
833 | ||
1c21a293 | 834 | static void __init clocksource_init(void) |
4a4cfe38 TB |
835 | { |
836 | struct clocksource *clock; | |
837 | ||
838 | if (__USE_RTC()) | |
839 | clock = &clocksource_rtc; | |
840 | else | |
841 | clock = &clocksource_timebase; | |
842 | ||
11b8633a | 843 | if (clocksource_register_hz(clock, tb_ticks_per_sec)) { |
4a4cfe38 TB |
844 | printk(KERN_ERR "clocksource: %s is already registered\n", |
845 | clock->name); | |
846 | return; | |
847 | } | |
848 | ||
849 | printk(KERN_INFO "clocksource: %s mult[%x] shift[%d] registered\n", | |
850 | clock->name, clock->mult, clock->shift); | |
851 | } | |
852 | ||
d831d0b8 TB |
853 | static int decrementer_set_next_event(unsigned long evt, |
854 | struct clock_event_device *dev) | |
855 | { | |
69111bac | 856 | __this_cpu_write(decrementers_next_tb, get_tb_or_rtc() + evt); |
d831d0b8 | 857 | set_dec(evt); |
0215f7d8 BH |
858 | |
859 | /* We may have raced with new irq work */ | |
860 | if (test_irq_work_pending()) | |
861 | set_dec(1); | |
862 | ||
d831d0b8 TB |
863 | return 0; |
864 | } | |
865 | ||
37a13e78 | 866 | static int decrementer_shutdown(struct clock_event_device *dev) |
d831d0b8 | 867 | { |
37a13e78 VK |
868 | decrementer_set_next_event(DECREMENTER_MAX, dev); |
869 | return 0; | |
d831d0b8 TB |
870 | } |
871 | ||
1b67bee1 SB |
872 | /* Interrupt handler for the timer broadcast IPI */ |
873 | void tick_broadcast_ipi_handler(void) | |
874 | { | |
69111bac | 875 | u64 *next_tb = this_cpu_ptr(&decrementers_next_tb); |
1b783955 PM |
876 | |
877 | *next_tb = get_tb_or_rtc(); | |
878 | __timer_interrupt(); | |
1b67bee1 SB |
879 | } |
880 | ||
d831d0b8 TB |
881 | static void register_decrementer_clockevent(int cpu) |
882 | { | |
7df10275 | 883 | struct clock_event_device *dec = &per_cpu(decrementers, cpu); |
d831d0b8 TB |
884 | |
885 | *dec = decrementer_clockevent; | |
320ab2b0 | 886 | dec->cpumask = cpumask_of(cpu); |
d831d0b8 | 887 | |
b919ee82 AB |
888 | printk_once(KERN_DEBUG "clockevent: %s mult[%x] shift[%d] cpu[%d]\n", |
889 | dec->name, dec->mult, dec->shift, cpu); | |
d831d0b8 TB |
890 | |
891 | clockevents_register_device(dec); | |
892 | } | |
893 | ||
c481887f | 894 | static void __init init_decrementer_clockevent(void) |
d831d0b8 TB |
895 | { |
896 | int cpu = smp_processor_id(); | |
897 | ||
d8afc6fd AB |
898 | clockevents_calc_mult_shift(&decrementer_clockevent, ppc_tb_freq, 4); |
899 | ||
d831d0b8 TB |
900 | decrementer_clockevent.max_delta_ns = |
901 | clockevent_delta2ns(DECREMENTER_MAX, &decrementer_clockevent); | |
43875cc0 PM |
902 | decrementer_clockevent.min_delta_ns = |
903 | clockevent_delta2ns(2, &decrementer_clockevent); | |
d831d0b8 TB |
904 | |
905 | register_decrementer_clockevent(cpu); | |
906 | } | |
907 | ||
908 | void secondary_cpu_time_init(void) | |
909 | { | |
77c0a700 BH |
910 | /* Start the decrementer on CPUs that have manual control |
911 | * such as BookE | |
912 | */ | |
913 | start_cpu_decrementer(); | |
914 | ||
d831d0b8 TB |
915 | /* FIME: Should make unrelatred change to move snapshot_timebase |
916 | * call here ! */ | |
917 | register_decrementer_clockevent(smp_processor_id()); | |
918 | } | |
919 | ||
f2783c15 | 920 | /* This function is only called on the boot processor */ |
1da177e4 LT |
921 | void __init time_init(void) |
922 | { | |
1da177e4 | 923 | struct div_result res; |
d75d68cf | 924 | u64 scale; |
f2783c15 PM |
925 | unsigned shift; |
926 | ||
96c44507 PM |
927 | if (__USE_RTC()) { |
928 | /* 601 processor: dec counts down by 128 every 128ns */ | |
929 | ppc_tb_freq = 1000000000; | |
96c44507 PM |
930 | } else { |
931 | /* Normal PowerPC with timebase register */ | |
932 | ppc_md.calibrate_decr(); | |
224ad80a | 933 | printk(KERN_DEBUG "time_init: decrementer frequency = %lu.%.6lu MHz\n", |
96c44507 | 934 | ppc_tb_freq / 1000000, ppc_tb_freq % 1000000); |
224ad80a | 935 | printk(KERN_DEBUG "time_init: processor frequency = %lu.%.6lu MHz\n", |
96c44507 | 936 | ppc_proc_freq / 1000000, ppc_proc_freq % 1000000); |
96c44507 | 937 | } |
374e99d4 PM |
938 | |
939 | tb_ticks_per_jiffy = ppc_tb_freq / HZ; | |
092b8f34 | 940 | tb_ticks_per_sec = ppc_tb_freq; |
374e99d4 | 941 | tb_ticks_per_usec = ppc_tb_freq / 1000000; |
c6622f63 | 942 | calc_cputime_factors(); |
a42548a1 | 943 | setup_cputime_one_jiffy(); |
092b8f34 | 944 | |
1da177e4 LT |
945 | /* |
946 | * Compute scale factor for sched_clock. | |
947 | * The calibrate_decr() function has set tb_ticks_per_sec, | |
948 | * which is the timebase frequency. | |
949 | * We compute 1e9 * 2^64 / tb_ticks_per_sec and interpret | |
950 | * the 128-bit result as a 64.64 fixed-point number. | |
951 | * We then shift that number right until it is less than 1.0, | |
952 | * giving us the scale factor and shift count to use in | |
953 | * sched_clock(). | |
954 | */ | |
955 | div128_by_32(1000000000, 0, tb_ticks_per_sec, &res); | |
956 | scale = res.result_low; | |
957 | for (shift = 0; res.result_high != 0; ++shift) { | |
958 | scale = (scale >> 1) | (res.result_high << 63); | |
959 | res.result_high >>= 1; | |
960 | } | |
961 | tb_to_ns_scale = scale; | |
962 | tb_to_ns_shift = shift; | |
fc9069fe | 963 | /* Save the current timebase to pretty up CONFIG_PRINTK_TIME */ |
c27da339 | 964 | boot_tb = get_tb_or_rtc(); |
1da177e4 | 965 | |
092b8f34 | 966 | /* If platform provided a timezone (pmac), we correct the time */ |
621692cb | 967 | if (timezone_offset) { |
092b8f34 PM |
968 | sys_tz.tz_minuteswest = -timezone_offset / 60; |
969 | sys_tz.tz_dsttime = 0; | |
621692cb | 970 | } |
092b8f34 | 971 | |
a7f290da BH |
972 | vdso_data->tb_update_count = 0; |
973 | vdso_data->tb_ticks_per_sec = tb_ticks_per_sec; | |
1da177e4 | 974 | |
77c0a700 BH |
975 | /* Start the decrementer on CPUs that have manual control |
976 | * such as BookE | |
977 | */ | |
978 | start_cpu_decrementer(); | |
979 | ||
f5339277 SR |
980 | /* Register the clocksource */ |
981 | clocksource_init(); | |
4a4cfe38 | 982 | |
d831d0b8 | 983 | init_decrementer_clockevent(); |
0d948730 | 984 | tick_setup_hrtimer_broadcast(); |
f0d37300 KH |
985 | |
986 | #ifdef CONFIG_COMMON_CLK | |
987 | of_clk_init(NULL); | |
988 | #endif | |
1da177e4 LT |
989 | } |
990 | ||
1da177e4 | 991 | |
1da177e4 LT |
992 | #define FEBRUARY 2 |
993 | #define STARTOFTIME 1970 | |
994 | #define SECDAY 86400L | |
995 | #define SECYR (SECDAY * 365) | |
f2783c15 PM |
996 | #define leapyear(year) ((year) % 4 == 0 && \ |
997 | ((year) % 100 != 0 || (year) % 400 == 0)) | |
1da177e4 LT |
998 | #define days_in_year(a) (leapyear(a) ? 366 : 365) |
999 | #define days_in_month(a) (month_days[(a) - 1]) | |
1000 | ||
1001 | static int month_days[12] = { | |
1002 | 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 | |
1003 | }; | |
1004 | ||
1da177e4 LT |
1005 | void to_tm(int tim, struct rtc_time * tm) |
1006 | { | |
1007 | register int i; | |
1008 | register long hms, day; | |
1009 | ||
1010 | day = tim / SECDAY; | |
1011 | hms = tim % SECDAY; | |
1012 | ||
1013 | /* Hours, minutes, seconds are easy */ | |
1014 | tm->tm_hour = hms / 3600; | |
1015 | tm->tm_min = (hms % 3600) / 60; | |
1016 | tm->tm_sec = (hms % 3600) % 60; | |
1017 | ||
1018 | /* Number of years in days */ | |
1019 | for (i = STARTOFTIME; day >= days_in_year(i); i++) | |
1020 | day -= days_in_year(i); | |
1021 | tm->tm_year = i; | |
1022 | ||
1023 | /* Number of months in days left */ | |
1024 | if (leapyear(tm->tm_year)) | |
1025 | days_in_month(FEBRUARY) = 29; | |
1026 | for (i = 1; day >= days_in_month(i); i++) | |
1027 | day -= days_in_month(i); | |
1028 | days_in_month(FEBRUARY) = 28; | |
1029 | tm->tm_mon = i; | |
1030 | ||
1031 | /* Days are what is left over (+1) from all that. */ | |
1032 | tm->tm_mday = day + 1; | |
1033 | ||
1034 | /* | |
00b912b0 | 1035 | * No-one uses the day of the week. |
1da177e4 | 1036 | */ |
00b912b0 | 1037 | tm->tm_wday = -1; |
1da177e4 | 1038 | } |
e1802b06 | 1039 | EXPORT_SYMBOL(to_tm); |
1da177e4 | 1040 | |
1da177e4 LT |
1041 | /* |
1042 | * Divide a 128-bit dividend by a 32-bit divisor, leaving a 128 bit | |
1043 | * result. | |
1044 | */ | |
f2783c15 PM |
1045 | void div128_by_32(u64 dividend_high, u64 dividend_low, |
1046 | unsigned divisor, struct div_result *dr) | |
1da177e4 | 1047 | { |
f2783c15 PM |
1048 | unsigned long a, b, c, d; |
1049 | unsigned long w, x, y, z; | |
1050 | u64 ra, rb, rc; | |
1da177e4 LT |
1051 | |
1052 | a = dividend_high >> 32; | |
1053 | b = dividend_high & 0xffffffff; | |
1054 | c = dividend_low >> 32; | |
1055 | d = dividend_low & 0xffffffff; | |
1056 | ||
f2783c15 PM |
1057 | w = a / divisor; |
1058 | ra = ((u64)(a - (w * divisor)) << 32) + b; | |
1059 | ||
f2783c15 PM |
1060 | rb = ((u64) do_div(ra, divisor) << 32) + c; |
1061 | x = ra; | |
1da177e4 | 1062 | |
f2783c15 PM |
1063 | rc = ((u64) do_div(rb, divisor) << 32) + d; |
1064 | y = rb; | |
1065 | ||
1066 | do_div(rc, divisor); | |
1067 | z = rc; | |
1da177e4 | 1068 | |
f2783c15 PM |
1069 | dr->result_high = ((u64)w << 32) + x; |
1070 | dr->result_low = ((u64)y << 32) + z; | |
1da177e4 LT |
1071 | |
1072 | } | |
bcd68a70 | 1073 | |
177996e6 BH |
1074 | /* We don't need to calibrate delay, we use the CPU timebase for that */ |
1075 | void calibrate_delay(void) | |
1076 | { | |
1077 | /* Some generic code (such as spinlock debug) use loops_per_jiffy | |
1078 | * as the number of __delay(1) in a jiffy, so make it so | |
1079 | */ | |
1080 | loops_per_jiffy = tb_ticks_per_jiffy; | |
1081 | } | |
1082 | ||
bcd68a70 GU |
1083 | static int __init rtc_init(void) |
1084 | { | |
1085 | struct platform_device *pdev; | |
1086 | ||
1087 | if (!ppc_md.get_rtc_time) | |
1088 | return -ENODEV; | |
1089 | ||
1090 | pdev = platform_device_register_simple("rtc-generic", -1, NULL, 0); | |
bcd68a70 | 1091 | |
8c6ffba0 | 1092 | return PTR_ERR_OR_ZERO(pdev); |
bcd68a70 GU |
1093 | } |
1094 | ||
8f6b9512 | 1095 | device_initcall(rtc_init); |