Commit | Line | Data |
---|---|---|
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 | |
20 | * measurement at boot time. (for iSeries, we calibrate the timebase | |
21 | * against the Titan chip's clock.) | |
22 | * - for astronomical applications: add a new function to get | |
23 | * non ambiguous timestamps even around leap seconds. This needs | |
24 | * a new timestamp format and a good name. | |
25 | * | |
26 | * 1997-09-10 Updated NTP code according to technical memorandum Jan '96 | |
27 | * "A Kernel Model for Precision Timekeeping" by Dave Mills | |
28 | * | |
29 | * This program is free software; you can redistribute it and/or | |
30 | * modify it under the terms of the GNU General Public License | |
31 | * as published by the Free Software Foundation; either version | |
32 | * 2 of the License, or (at your option) any later version. | |
33 | */ | |
34 | ||
1da177e4 LT |
35 | #include <linux/errno.h> |
36 | #include <linux/module.h> | |
37 | #include <linux/sched.h> | |
38 | #include <linux/kernel.h> | |
39 | #include <linux/param.h> | |
40 | #include <linux/string.h> | |
41 | #include <linux/mm.h> | |
42 | #include <linux/interrupt.h> | |
43 | #include <linux/timex.h> | |
44 | #include <linux/kernel_stat.h> | |
1da177e4 LT |
45 | #include <linux/time.h> |
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> |
6795b85c | 57 | #include <asm/trace.h> |
1da177e4 | 58 | |
1da177e4 LT |
59 | #include <asm/io.h> |
60 | #include <asm/processor.h> | |
61 | #include <asm/nvram.h> | |
62 | #include <asm/cache.h> | |
63 | #include <asm/machdep.h> | |
1da177e4 LT |
64 | #include <asm/uaccess.h> |
65 | #include <asm/time.h> | |
1da177e4 | 66 | #include <asm/prom.h> |
f2783c15 PM |
67 | #include <asm/irq.h> |
68 | #include <asm/div64.h> | |
2249ca9d | 69 | #include <asm/smp.h> |
a7f290da | 70 | #include <asm/vdso_datapage.h> |
1ababe11 | 71 | #include <asm/firmware.h> |
06b8e878 | 72 | #include <asm/cputime.h> |
f2783c15 | 73 | #ifdef CONFIG_PPC_ISERIES |
8875ccfb | 74 | #include <asm/iseries/it_lp_queue.h> |
8021b8a7 | 75 | #include <asm/iseries/hv_call_xm.h> |
f2783c15 | 76 | #endif |
1da177e4 | 77 | |
4a4cfe38 TB |
78 | /* powerpc clocksource/clockevent code */ |
79 | ||
d831d0b8 | 80 | #include <linux/clockchips.h> |
4a4cfe38 TB |
81 | #include <linux/clocksource.h> |
82 | ||
8e19608e | 83 | static cycle_t rtc_read(struct clocksource *); |
4a4cfe38 TB |
84 | static struct clocksource clocksource_rtc = { |
85 | .name = "rtc", | |
86 | .rating = 400, | |
87 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | |
88 | .mask = CLOCKSOURCE_MASK(64), | |
89 | .shift = 22, | |
90 | .mult = 0, /* To be filled in */ | |
91 | .read = rtc_read, | |
92 | }; | |
93 | ||
8e19608e | 94 | static cycle_t timebase_read(struct clocksource *); |
4a4cfe38 TB |
95 | static struct clocksource clocksource_timebase = { |
96 | .name = "timebase", | |
97 | .rating = 400, | |
98 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | |
99 | .mask = CLOCKSOURCE_MASK(64), | |
100 | .shift = 22, | |
101 | .mult = 0, /* To be filled in */ | |
102 | .read = timebase_read, | |
103 | }; | |
104 | ||
d831d0b8 TB |
105 | #define DECREMENTER_MAX 0x7fffffff |
106 | ||
107 | static int decrementer_set_next_event(unsigned long evt, | |
108 | struct clock_event_device *dev); | |
109 | static void decrementer_set_mode(enum clock_event_mode mode, | |
110 | struct clock_event_device *dev); | |
111 | ||
112 | static struct clock_event_device decrementer_clockevent = { | |
113 | .name = "decrementer", | |
114 | .rating = 200, | |
8d165db1 | 115 | .shift = 0, /* To be filled in */ |
d831d0b8 TB |
116 | .mult = 0, /* To be filled in */ |
117 | .irq = 0, | |
118 | .set_next_event = decrementer_set_next_event, | |
119 | .set_mode = decrementer_set_mode, | |
120 | .features = CLOCK_EVT_FEAT_ONESHOT, | |
121 | }; | |
122 | ||
6e6b44e8 MM |
123 | struct decrementer_clock { |
124 | struct clock_event_device event; | |
125 | u64 next_tb; | |
126 | }; | |
127 | ||
128 | static DEFINE_PER_CPU(struct decrementer_clock, decrementers); | |
d831d0b8 | 129 | |
1da177e4 | 130 | #ifdef CONFIG_PPC_ISERIES |
71712b45 TB |
131 | static unsigned long __initdata iSeries_recal_titan; |
132 | static signed long __initdata iSeries_recal_tb; | |
4a4cfe38 TB |
133 | |
134 | /* Forward declaration is only needed for iSereis compiles */ | |
1c21a293 | 135 | static void __init clocksource_init(void); |
1da177e4 LT |
136 | #endif |
137 | ||
138 | #define XSEC_PER_SEC (1024*1024) | |
139 | ||
f2783c15 PM |
140 | #ifdef CONFIG_PPC64 |
141 | #define SCALE_XSEC(xsec, max) (((xsec) * max) / XSEC_PER_SEC) | |
142 | #else | |
143 | /* compute ((xsec << 12) * max) >> 32 */ | |
144 | #define SCALE_XSEC(xsec, max) mulhwu((xsec) << 12, max) | |
145 | #endif | |
146 | ||
1da177e4 LT |
147 | unsigned long tb_ticks_per_jiffy; |
148 | unsigned long tb_ticks_per_usec = 100; /* sane default */ | |
149 | EXPORT_SYMBOL(tb_ticks_per_usec); | |
150 | unsigned long tb_ticks_per_sec; | |
2cf82c02 | 151 | EXPORT_SYMBOL(tb_ticks_per_sec); /* for cputime_t conversions */ |
092b8f34 | 152 | |
1da177e4 | 153 | DEFINE_SPINLOCK(rtc_lock); |
6ae3db11 | 154 | EXPORT_SYMBOL_GPL(rtc_lock); |
1da177e4 | 155 | |
fc9069fe TB |
156 | static u64 tb_to_ns_scale __read_mostly; |
157 | static unsigned tb_to_ns_shift __read_mostly; | |
364a1246 | 158 | static u64 boot_tb __read_mostly; |
1da177e4 | 159 | |
1da177e4 | 160 | extern struct timezone sys_tz; |
f2783c15 | 161 | static long timezone_offset; |
1da177e4 | 162 | |
10f7e7c1 | 163 | unsigned long ppc_proc_freq; |
55ec2fca | 164 | EXPORT_SYMBOL_GPL(ppc_proc_freq); |
10f7e7c1 | 165 | unsigned long ppc_tb_freq; |
55ec2fca | 166 | EXPORT_SYMBOL_GPL(ppc_tb_freq); |
96c44507 | 167 | |
c6622f63 PM |
168 | #ifdef CONFIG_VIRT_CPU_ACCOUNTING |
169 | /* | |
170 | * Factors for converting from cputime_t (timebase ticks) to | |
171 | * jiffies, milliseconds, seconds, and clock_t (1/USER_HZ seconds). | |
172 | * These are all stored as 0.64 fixed-point binary fractions. | |
173 | */ | |
174 | u64 __cputime_jiffies_factor; | |
2cf82c02 | 175 | EXPORT_SYMBOL(__cputime_jiffies_factor); |
c6622f63 | 176 | u64 __cputime_msec_factor; |
2cf82c02 | 177 | EXPORT_SYMBOL(__cputime_msec_factor); |
c6622f63 | 178 | u64 __cputime_sec_factor; |
2cf82c02 | 179 | EXPORT_SYMBOL(__cputime_sec_factor); |
c6622f63 | 180 | u64 __cputime_clockt_factor; |
2cf82c02 | 181 | EXPORT_SYMBOL(__cputime_clockt_factor); |
06b8e878 MN |
182 | DEFINE_PER_CPU(unsigned long, cputime_last_delta); |
183 | DEFINE_PER_CPU(unsigned long, cputime_scaled_last_delta); | |
c6622f63 | 184 | |
a42548a1 SG |
185 | cputime_t cputime_one_jiffy; |
186 | ||
872e439a PM |
187 | void (*dtl_consumer)(struct dtl_entry *, u64); |
188 | ||
c6622f63 PM |
189 | static void calc_cputime_factors(void) |
190 | { | |
191 | struct div_result res; | |
192 | ||
193 | div128_by_32(HZ, 0, tb_ticks_per_sec, &res); | |
194 | __cputime_jiffies_factor = res.result_low; | |
195 | div128_by_32(1000, 0, tb_ticks_per_sec, &res); | |
196 | __cputime_msec_factor = res.result_low; | |
197 | div128_by_32(1, 0, tb_ticks_per_sec, &res); | |
198 | __cputime_sec_factor = res.result_low; | |
199 | div128_by_32(USER_HZ, 0, tb_ticks_per_sec, &res); | |
200 | __cputime_clockt_factor = res.result_low; | |
201 | } | |
202 | ||
203 | /* | |
cf9efce0 PM |
204 | * Read the SPURR on systems that have it, otherwise the PURR, |
205 | * or if that doesn't exist return the timebase value passed in. | |
c6622f63 | 206 | */ |
cf9efce0 | 207 | static u64 read_spurr(u64 tb) |
c6622f63 | 208 | { |
cf9efce0 PM |
209 | if (cpu_has_feature(CPU_FTR_SPURR)) |
210 | return mfspr(SPRN_SPURR); | |
c6622f63 PM |
211 | if (cpu_has_feature(CPU_FTR_PURR)) |
212 | return mfspr(SPRN_PURR); | |
cf9efce0 | 213 | return tb; |
c6622f63 PM |
214 | } |
215 | ||
cf9efce0 PM |
216 | #ifdef CONFIG_PPC_SPLPAR |
217 | ||
4603ac18 | 218 | /* |
cf9efce0 PM |
219 | * Scan the dispatch trace log and count up the stolen time. |
220 | * Should be called with interrupts disabled. | |
4603ac18 | 221 | */ |
cf9efce0 | 222 | static u64 scan_dispatch_log(u64 stop_tb) |
4603ac18 | 223 | { |
872e439a | 224 | u64 i = local_paca->dtl_ridx; |
cf9efce0 PM |
225 | struct dtl_entry *dtl = local_paca->dtl_curr; |
226 | struct dtl_entry *dtl_end = local_paca->dispatch_log_end; | |
227 | struct lppaca *vpa = local_paca->lppaca_ptr; | |
228 | u64 tb_delta; | |
229 | u64 stolen = 0; | |
230 | u64 dtb; | |
231 | ||
232 | if (i == vpa->dtl_idx) | |
233 | return 0; | |
234 | while (i < vpa->dtl_idx) { | |
872e439a PM |
235 | if (dtl_consumer) |
236 | dtl_consumer(dtl, i); | |
cf9efce0 PM |
237 | dtb = dtl->timebase; |
238 | tb_delta = dtl->enqueue_to_dispatch_time + | |
239 | dtl->ready_to_enqueue_time; | |
240 | barrier(); | |
241 | if (i + N_DISPATCH_LOG < vpa->dtl_idx) { | |
242 | /* buffer has overflowed */ | |
243 | i = vpa->dtl_idx - N_DISPATCH_LOG; | |
244 | dtl = local_paca->dispatch_log + (i % N_DISPATCH_LOG); | |
245 | continue; | |
246 | } | |
247 | if (dtb > stop_tb) | |
248 | break; | |
249 | stolen += tb_delta; | |
250 | ++i; | |
251 | ++dtl; | |
252 | if (dtl == dtl_end) | |
253 | dtl = local_paca->dispatch_log; | |
254 | } | |
255 | local_paca->dtl_ridx = i; | |
256 | local_paca->dtl_curr = dtl; | |
257 | return stolen; | |
4603ac18 MN |
258 | } |
259 | ||
cf9efce0 PM |
260 | /* |
261 | * Accumulate stolen time by scanning the dispatch trace log. | |
262 | * Called on entry from user mode. | |
263 | */ | |
264 | void accumulate_stolen_time(void) | |
265 | { | |
266 | u64 sst, ust; | |
267 | ||
b18ae08d TH |
268 | u8 save_soft_enabled = local_paca->soft_enabled; |
269 | u8 save_hard_enabled = local_paca->hard_enabled; | |
270 | ||
271 | /* We are called early in the exception entry, before | |
272 | * soft/hard_enabled are sync'ed to the expected state | |
273 | * for the exception. We are hard disabled but the PACA | |
274 | * needs to reflect that so various debug stuff doesn't | |
275 | * complain | |
276 | */ | |
277 | local_paca->soft_enabled = 0; | |
278 | local_paca->hard_enabled = 0; | |
279 | ||
280 | sst = scan_dispatch_log(local_paca->starttime_user); | |
281 | ust = scan_dispatch_log(local_paca->starttime); | |
282 | local_paca->system_time -= sst; | |
283 | local_paca->user_time -= ust; | |
284 | local_paca->stolen_time += ust + sst; | |
285 | ||
286 | local_paca->soft_enabled = save_soft_enabled; | |
287 | local_paca->hard_enabled = save_hard_enabled; | |
cf9efce0 PM |
288 | } |
289 | ||
290 | static inline u64 calculate_stolen_time(u64 stop_tb) | |
291 | { | |
292 | u64 stolen = 0; | |
293 | ||
294 | if (get_paca()->dtl_ridx != get_paca()->lppaca_ptr->dtl_idx) { | |
295 | stolen = scan_dispatch_log(stop_tb); | |
296 | get_paca()->system_time -= stolen; | |
297 | } | |
298 | ||
299 | stolen += get_paca()->stolen_time; | |
300 | get_paca()->stolen_time = 0; | |
301 | return stolen; | |
4603ac18 MN |
302 | } |
303 | ||
cf9efce0 PM |
304 | #else /* CONFIG_PPC_SPLPAR */ |
305 | static inline u64 calculate_stolen_time(u64 stop_tb) | |
306 | { | |
307 | return 0; | |
308 | } | |
309 | ||
310 | #endif /* CONFIG_PPC_SPLPAR */ | |
311 | ||
c6622f63 PM |
312 | /* |
313 | * Account time for a transition between system, hard irq | |
314 | * or soft irq state. | |
315 | */ | |
316 | void account_system_vtime(struct task_struct *tsk) | |
317 | { | |
cf9efce0 | 318 | u64 now, nowscaled, delta, deltascaled; |
c6622f63 | 319 | unsigned long flags; |
cf9efce0 | 320 | u64 stolen, udelta, sys_scaled, user_scaled; |
c6622f63 PM |
321 | |
322 | local_irq_save(flags); | |
cf9efce0 | 323 | now = mftb(); |
4603ac18 | 324 | nowscaled = read_spurr(now); |
cf9efce0 PM |
325 | get_paca()->system_time += now - get_paca()->starttime; |
326 | get_paca()->starttime = now; | |
4603ac18 MN |
327 | deltascaled = nowscaled - get_paca()->startspurr; |
328 | get_paca()->startspurr = nowscaled; | |
cf9efce0 PM |
329 | |
330 | stolen = calculate_stolen_time(now); | |
331 | ||
332 | delta = get_paca()->system_time; | |
333 | get_paca()->system_time = 0; | |
334 | udelta = get_paca()->user_time - get_paca()->utime_sspurr; | |
335 | get_paca()->utime_sspurr = get_paca()->user_time; | |
336 | ||
337 | /* | |
338 | * Because we don't read the SPURR on every kernel entry/exit, | |
339 | * deltascaled includes both user and system SPURR ticks. | |
340 | * Apportion these ticks to system SPURR ticks and user | |
341 | * SPURR ticks in the same ratio as the system time (delta) | |
342 | * and user time (udelta) values obtained from the timebase | |
343 | * over the same interval. The system ticks get accounted here; | |
344 | * the user ticks get saved up in paca->user_time_scaled to be | |
345 | * used by account_process_tick. | |
346 | */ | |
347 | sys_scaled = delta; | |
348 | user_scaled = udelta; | |
349 | if (deltascaled != delta + udelta) { | |
350 | if (udelta) { | |
351 | sys_scaled = deltascaled * delta / (delta + udelta); | |
352 | user_scaled = deltascaled - sys_scaled; | |
353 | } else { | |
354 | sys_scaled = deltascaled; | |
355 | } | |
356 | } | |
357 | get_paca()->user_time_scaled += user_scaled; | |
358 | ||
359 | if (in_irq() || idle_task(smp_processor_id()) != tsk) { | |
360 | account_system_time(tsk, 0, delta, sys_scaled); | |
361 | if (stolen) | |
362 | account_steal_time(stolen); | |
363 | } else { | |
364 | account_idle_time(delta + stolen); | |
c6622f63 | 365 | } |
c6622f63 PM |
366 | local_irq_restore(flags); |
367 | } | |
4ab79aa8 | 368 | EXPORT_SYMBOL_GPL(account_system_vtime); |
c6622f63 PM |
369 | |
370 | /* | |
371 | * Transfer the user and system times accumulated in the paca | |
372 | * by the exception entry and exit code to the generic process | |
373 | * user and system time records. | |
374 | * Must be called with interrupts disabled. | |
cf9efce0 PM |
375 | * Assumes that account_system_vtime() has been called recently |
376 | * (i.e. since the last entry from usermode) so that | |
377 | * get_paca()->user_time_scaled is up to date. | |
c6622f63 | 378 | */ |
fa13a5a1 | 379 | void account_process_tick(struct task_struct *tsk, int user_tick) |
c6622f63 | 380 | { |
4603ac18 | 381 | cputime_t utime, utimescaled; |
c6622f63 PM |
382 | |
383 | utime = get_paca()->user_time; | |
cf9efce0 | 384 | utimescaled = get_paca()->user_time_scaled; |
c6622f63 | 385 | get_paca()->user_time = 0; |
cf9efce0 PM |
386 | get_paca()->user_time_scaled = 0; |
387 | get_paca()->utime_sspurr = 0; | |
457533a7 | 388 | account_user_time(tsk, utime, utimescaled); |
c6622f63 PM |
389 | } |
390 | ||
c6622f63 PM |
391 | #else /* ! CONFIG_VIRT_CPU_ACCOUNTING */ |
392 | #define calc_cputime_factors() | |
c6622f63 PM |
393 | #endif |
394 | ||
6defa38b PM |
395 | void __delay(unsigned long loops) |
396 | { | |
397 | unsigned long start; | |
398 | int diff; | |
399 | ||
400 | if (__USE_RTC()) { | |
401 | start = get_rtcl(); | |
402 | do { | |
403 | /* the RTCL register wraps at 1000000000 */ | |
404 | diff = get_rtcl() - start; | |
405 | if (diff < 0) | |
406 | diff += 1000000000; | |
407 | } while (diff < loops); | |
408 | } else { | |
409 | start = get_tbl(); | |
410 | while (get_tbl() - start < loops) | |
411 | HMT_low(); | |
412 | HMT_medium(); | |
413 | } | |
414 | } | |
415 | EXPORT_SYMBOL(__delay); | |
416 | ||
417 | void udelay(unsigned long usecs) | |
418 | { | |
419 | __delay(tb_ticks_per_usec * usecs); | |
420 | } | |
421 | EXPORT_SYMBOL(udelay); | |
422 | ||
1da177e4 LT |
423 | #ifdef CONFIG_SMP |
424 | unsigned long profile_pc(struct pt_regs *regs) | |
425 | { | |
426 | unsigned long pc = instruction_pointer(regs); | |
427 | ||
428 | if (in_lock_functions(pc)) | |
429 | return regs->link; | |
430 | ||
431 | return pc; | |
432 | } | |
433 | EXPORT_SYMBOL(profile_pc); | |
434 | #endif | |
435 | ||
436 | #ifdef CONFIG_PPC_ISERIES | |
437 | ||
438 | /* | |
439 | * This function recalibrates the timebase based on the 49-bit time-of-day | |
440 | * value in the Titan chip. The Titan is much more accurate than the value | |
441 | * returned by the service processor for the timebase frequency. | |
442 | */ | |
443 | ||
71712b45 | 444 | static int __init iSeries_tb_recal(void) |
1da177e4 | 445 | { |
1da177e4 | 446 | unsigned long titan, tb; |
71712b45 TB |
447 | |
448 | /* Make sure we only run on iSeries */ | |
449 | if (!firmware_has_feature(FW_FEATURE_ISERIES)) | |
450 | return -ENODEV; | |
451 | ||
1da177e4 LT |
452 | tb = get_tb(); |
453 | titan = HvCallXm_loadTod(); | |
454 | if ( iSeries_recal_titan ) { | |
455 | unsigned long tb_ticks = tb - iSeries_recal_tb; | |
456 | unsigned long titan_usec = (titan - iSeries_recal_titan) >> 12; | |
457 | unsigned long new_tb_ticks_per_sec = (tb_ticks * USEC_PER_SEC)/titan_usec; | |
14ea58ad JL |
458 | unsigned long new_tb_ticks_per_jiffy = |
459 | DIV_ROUND_CLOSEST(new_tb_ticks_per_sec, HZ); | |
1da177e4 LT |
460 | long tick_diff = new_tb_ticks_per_jiffy - tb_ticks_per_jiffy; |
461 | char sign = '+'; | |
462 | /* make sure tb_ticks_per_sec and tb_ticks_per_jiffy are consistent */ | |
463 | new_tb_ticks_per_sec = new_tb_ticks_per_jiffy * HZ; | |
464 | ||
465 | if ( tick_diff < 0 ) { | |
466 | tick_diff = -tick_diff; | |
467 | sign = '-'; | |
468 | } | |
469 | if ( tick_diff ) { | |
470 | if ( tick_diff < tb_ticks_per_jiffy/25 ) { | |
471 | printk( "Titan recalibrate: new tb_ticks_per_jiffy = %lu (%c%ld)\n", | |
472 | new_tb_ticks_per_jiffy, sign, tick_diff ); | |
473 | tb_ticks_per_jiffy = new_tb_ticks_per_jiffy; | |
474 | tb_ticks_per_sec = new_tb_ticks_per_sec; | |
c6622f63 | 475 | calc_cputime_factors(); |
a7f290da | 476 | vdso_data->tb_ticks_per_sec = tb_ticks_per_sec; |
a42548a1 | 477 | setup_cputime_one_jiffy(); |
1da177e4 LT |
478 | } |
479 | else { | |
480 | printk( "Titan recalibrate: FAILED (difference > 4 percent)\n" | |
481 | " new tb_ticks_per_jiffy = %lu\n" | |
482 | " old tb_ticks_per_jiffy = %lu\n", | |
483 | new_tb_ticks_per_jiffy, tb_ticks_per_jiffy ); | |
484 | } | |
485 | } | |
486 | } | |
487 | iSeries_recal_titan = titan; | |
488 | iSeries_recal_tb = tb; | |
71712b45 | 489 | |
4a4cfe38 TB |
490 | /* Called here as now we know accurate values for the timebase */ |
491 | clocksource_init(); | |
71712b45 | 492 | return 0; |
1da177e4 | 493 | } |
71712b45 TB |
494 | late_initcall(iSeries_tb_recal); |
495 | ||
496 | /* Called from platform early init */ | |
497 | void __init iSeries_time_init_early(void) | |
498 | { | |
499 | iSeries_recal_tb = get_tb(); | |
500 | iSeries_recal_titan = HvCallXm_loadTod(); | |
501 | } | |
502 | #endif /* CONFIG_PPC_ISERIES */ | |
1da177e4 | 503 | |
e360adbe | 504 | #ifdef CONFIG_IRQ_WORK |
105988c0 | 505 | |
0fe1ac48 PM |
506 | /* |
507 | * 64-bit uses a byte in the PACA, 32-bit uses a per-cpu variable... | |
508 | */ | |
509 | #ifdef CONFIG_PPC64 | |
e360adbe | 510 | static inline unsigned long test_irq_work_pending(void) |
105988c0 | 511 | { |
0fe1ac48 PM |
512 | unsigned long x; |
513 | ||
514 | asm volatile("lbz %0,%1(13)" | |
515 | : "=r" (x) | |
e360adbe | 516 | : "i" (offsetof(struct paca_struct, irq_work_pending))); |
0fe1ac48 PM |
517 | return x; |
518 | } | |
519 | ||
e360adbe | 520 | static inline void set_irq_work_pending_flag(void) |
0fe1ac48 PM |
521 | { |
522 | asm volatile("stb %0,%1(13)" : : | |
523 | "r" (1), | |
e360adbe | 524 | "i" (offsetof(struct paca_struct, irq_work_pending))); |
0fe1ac48 PM |
525 | } |
526 | ||
e360adbe | 527 | static inline void clear_irq_work_pending(void) |
0fe1ac48 PM |
528 | { |
529 | asm volatile("stb %0,%1(13)" : : | |
530 | "r" (0), | |
e360adbe | 531 | "i" (offsetof(struct paca_struct, irq_work_pending))); |
105988c0 PM |
532 | } |
533 | ||
0fe1ac48 PM |
534 | #else /* 32-bit */ |
535 | ||
e360adbe | 536 | DEFINE_PER_CPU(u8, irq_work_pending); |
0fe1ac48 | 537 | |
e360adbe PZ |
538 | #define set_irq_work_pending_flag() __get_cpu_var(irq_work_pending) = 1 |
539 | #define test_irq_work_pending() __get_cpu_var(irq_work_pending) | |
540 | #define clear_irq_work_pending() __get_cpu_var(irq_work_pending) = 0 | |
105988c0 | 541 | |
0fe1ac48 PM |
542 | #endif /* 32 vs 64 bit */ |
543 | ||
e360adbe | 544 | void set_irq_work_pending(void) |
0fe1ac48 PM |
545 | { |
546 | preempt_disable(); | |
e360adbe | 547 | set_irq_work_pending_flag(); |
0fe1ac48 PM |
548 | set_dec(1); |
549 | preempt_enable(); | |
550 | } | |
551 | ||
e360adbe | 552 | #else /* CONFIG_IRQ_WORK */ |
105988c0 | 553 | |
e360adbe PZ |
554 | #define test_irq_work_pending() 0 |
555 | #define clear_irq_work_pending() | |
105988c0 | 556 | |
e360adbe | 557 | #endif /* CONFIG_IRQ_WORK */ |
105988c0 | 558 | |
1da177e4 LT |
559 | /* |
560 | * For iSeries shared processors, we have to let the hypervisor | |
561 | * set the hardware decrementer. We set a virtual decrementer | |
562 | * in the lppaca and call the hypervisor if the virtual | |
563 | * decrementer is less than the current value in the hardware | |
564 | * decrementer. (almost always the new decrementer value will | |
565 | * be greater than the current hardware decementer so the hypervisor | |
566 | * call will not be needed) | |
567 | */ | |
568 | ||
1da177e4 LT |
569 | /* |
570 | * timer_interrupt - gets called when the decrementer overflows, | |
571 | * with interrupts disabled. | |
572 | */ | |
c7aeffc4 | 573 | void timer_interrupt(struct pt_regs * regs) |
1da177e4 | 574 | { |
7d12e780 | 575 | struct pt_regs *old_regs; |
6e6b44e8 MM |
576 | struct decrementer_clock *decrementer = &__get_cpu_var(decrementers); |
577 | struct clock_event_device *evt = &decrementer->event; | |
d968014b | 578 | u64 now; |
d831d0b8 | 579 | |
6795b85c AB |
580 | trace_timer_interrupt_entry(regs); |
581 | ||
89713ed1 AB |
582 | __get_cpu_var(irq_stat).timer_irqs++; |
583 | ||
d831d0b8 TB |
584 | /* Ensure a positive value is written to the decrementer, or else |
585 | * some CPUs will continuue to take decrementer exceptions */ | |
586 | set_dec(DECREMENTER_MAX); | |
f2783c15 | 587 | |
b0d278b7 | 588 | #if defined(CONFIG_PPC32) && defined(CONFIG_PMAC) |
f2783c15 PM |
589 | if (atomic_read(&ppc_n_lost_interrupts) != 0) |
590 | do_IRQ(regs); | |
591 | #endif | |
1da177e4 | 592 | |
7d12e780 | 593 | old_regs = set_irq_regs(regs); |
1da177e4 LT |
594 | irq_enter(); |
595 | ||
e360adbe PZ |
596 | if (test_irq_work_pending()) { |
597 | clear_irq_work_pending(); | |
598 | irq_work_run(); | |
0fe1ac48 PM |
599 | } |
600 | ||
f2783c15 | 601 | #ifdef CONFIG_PPC_ISERIES |
501b6d29 SR |
602 | if (firmware_has_feature(FW_FEATURE_ISERIES)) |
603 | get_lppaca()->int_dword.fields.decr_int = 0; | |
f2783c15 PM |
604 | #endif |
605 | ||
b0d278b7 PM |
606 | now = get_tb_or_rtc(); |
607 | if (now >= decrementer->next_tb) { | |
608 | decrementer->next_tb = ~(u64)0; | |
609 | if (evt->event_handler) | |
610 | evt->event_handler(evt); | |
611 | } else { | |
612 | now = decrementer->next_tb - now; | |
613 | if (now <= DECREMENTER_MAX) | |
614 | set_dec((int)now); | |
615 | } | |
1da177e4 LT |
616 | |
617 | #ifdef CONFIG_PPC_ISERIES | |
501b6d29 | 618 | if (firmware_has_feature(FW_FEATURE_ISERIES) && hvlpevent_is_pending()) |
35a84c2f | 619 | process_hvlpevents(); |
1da177e4 LT |
620 | #endif |
621 | ||
f2783c15 | 622 | #ifdef CONFIG_PPC64 |
8d15a3e5 | 623 | /* collect purr register values often, for accurate calculations */ |
1ababe11 | 624 | if (firmware_has_feature(FW_FEATURE_SPLPAR)) { |
1da177e4 LT |
625 | struct cpu_usage *cu = &__get_cpu_var(cpu_usage_array); |
626 | cu->current_tb = mfspr(SPRN_PURR); | |
627 | } | |
f2783c15 | 628 | #endif |
1da177e4 LT |
629 | |
630 | irq_exit(); | |
7d12e780 | 631 | set_irq_regs(old_regs); |
6795b85c AB |
632 | |
633 | trace_timer_interrupt_exit(regs); | |
1da177e4 LT |
634 | } |
635 | ||
7ac5dde9 | 636 | #ifdef CONFIG_SUSPEND |
d75d68cf | 637 | static void generic_suspend_disable_irqs(void) |
7ac5dde9 | 638 | { |
7ac5dde9 SW |
639 | /* Disable the decrementer, so that it doesn't interfere |
640 | * with suspending. | |
641 | */ | |
642 | ||
643 | set_dec(0x7fffffff); | |
644 | local_irq_disable(); | |
645 | set_dec(0x7fffffff); | |
646 | } | |
647 | ||
d75d68cf | 648 | static void generic_suspend_enable_irqs(void) |
7ac5dde9 | 649 | { |
7ac5dde9 | 650 | local_irq_enable(); |
7ac5dde9 SW |
651 | } |
652 | ||
653 | /* Overrides the weak version in kernel/power/main.c */ | |
654 | void arch_suspend_disable_irqs(void) | |
655 | { | |
656 | if (ppc_md.suspend_disable_irqs) | |
657 | ppc_md.suspend_disable_irqs(); | |
658 | generic_suspend_disable_irqs(); | |
659 | } | |
660 | ||
661 | /* Overrides the weak version in kernel/power/main.c */ | |
662 | void arch_suspend_enable_irqs(void) | |
663 | { | |
664 | generic_suspend_enable_irqs(); | |
665 | if (ppc_md.suspend_enable_irqs) | |
666 | ppc_md.suspend_enable_irqs(); | |
667 | } | |
668 | #endif | |
669 | ||
1da177e4 LT |
670 | /* |
671 | * Scheduler clock - returns current time in nanosec units. | |
672 | * | |
673 | * Note: mulhdu(a, b) (multiply high double unsigned) returns | |
674 | * the high 64 bits of a * b, i.e. (a * b) >> 64, where a and b | |
675 | * are 64-bit unsigned numbers. | |
676 | */ | |
677 | unsigned long long sched_clock(void) | |
678 | { | |
96c44507 PM |
679 | if (__USE_RTC()) |
680 | return get_rtc(); | |
fc9069fe | 681 | return mulhdu(get_tb() - boot_tb, tb_to_ns_scale) << tb_to_ns_shift; |
1da177e4 LT |
682 | } |
683 | ||
0bb474a4 | 684 | static int __init get_freq(char *name, int cells, unsigned long *val) |
10f7e7c1 AB |
685 | { |
686 | struct device_node *cpu; | |
a7f67bdf | 687 | const unsigned int *fp; |
0bb474a4 | 688 | int found = 0; |
10f7e7c1 | 689 | |
0bb474a4 | 690 | /* The cpu node should have timebase and clock frequency properties */ |
10f7e7c1 AB |
691 | cpu = of_find_node_by_type(NULL, "cpu"); |
692 | ||
d8a8188d | 693 | if (cpu) { |
e2eb6392 | 694 | fp = of_get_property(cpu, name, NULL); |
d8a8188d | 695 | if (fp) { |
0bb474a4 | 696 | found = 1; |
a4dc7ff0 | 697 | *val = of_read_ulong(fp, cells); |
10f7e7c1 | 698 | } |
0bb474a4 AB |
699 | |
700 | of_node_put(cpu); | |
10f7e7c1 | 701 | } |
0bb474a4 AB |
702 | |
703 | return found; | |
704 | } | |
705 | ||
77c0a700 BH |
706 | /* should become __cpuinit when secondary_cpu_time_init also is */ |
707 | void start_cpu_decrementer(void) | |
708 | { | |
709 | #if defined(CONFIG_BOOKE) || defined(CONFIG_40x) | |
710 | /* Clear any pending timer interrupts */ | |
711 | mtspr(SPRN_TSR, TSR_ENW | TSR_WIS | TSR_DIS | TSR_FIS); | |
712 | ||
713 | /* Enable decrementer interrupt */ | |
714 | mtspr(SPRN_TCR, TCR_DIE); | |
715 | #endif /* defined(CONFIG_BOOKE) || defined(CONFIG_40x) */ | |
716 | } | |
717 | ||
0bb474a4 AB |
718 | void __init generic_calibrate_decr(void) |
719 | { | |
720 | ppc_tb_freq = DEFAULT_TB_FREQ; /* hardcoded default */ | |
721 | ||
722 | if (!get_freq("ibm,extended-timebase-frequency", 2, &ppc_tb_freq) && | |
723 | !get_freq("timebase-frequency", 1, &ppc_tb_freq)) { | |
724 | ||
10f7e7c1 AB |
725 | printk(KERN_ERR "WARNING: Estimating decrementer frequency " |
726 | "(not found)\n"); | |
0bb474a4 | 727 | } |
10f7e7c1 | 728 | |
0bb474a4 AB |
729 | ppc_proc_freq = DEFAULT_PROC_FREQ; /* hardcoded default */ |
730 | ||
731 | if (!get_freq("ibm,extended-clock-frequency", 2, &ppc_proc_freq) && | |
732 | !get_freq("clock-frequency", 1, &ppc_proc_freq)) { | |
733 | ||
734 | printk(KERN_ERR "WARNING: Estimating processor frequency " | |
735 | "(not found)\n"); | |
10f7e7c1 | 736 | } |
10f7e7c1 | 737 | } |
10f7e7c1 | 738 | |
aa3be5f3 | 739 | int update_persistent_clock(struct timespec now) |
f2783c15 PM |
740 | { |
741 | struct rtc_time tm; | |
742 | ||
aa3be5f3 TB |
743 | if (!ppc_md.set_rtc_time) |
744 | return 0; | |
745 | ||
746 | to_tm(now.tv_sec + 1 + timezone_offset, &tm); | |
747 | tm.tm_year -= 1900; | |
748 | tm.tm_mon -= 1; | |
749 | ||
750 | return ppc_md.set_rtc_time(&tm); | |
751 | } | |
752 | ||
978d7eb3 | 753 | static void __read_persistent_clock(struct timespec *ts) |
aa3be5f3 TB |
754 | { |
755 | struct rtc_time tm; | |
756 | static int first = 1; | |
757 | ||
d90246cd | 758 | ts->tv_nsec = 0; |
aa3be5f3 TB |
759 | /* XXX this is a litle fragile but will work okay in the short term */ |
760 | if (first) { | |
761 | first = 0; | |
762 | if (ppc_md.time_init) | |
763 | timezone_offset = ppc_md.time_init(); | |
764 | ||
765 | /* get_boot_time() isn't guaranteed to be safe to call late */ | |
d90246cd MS |
766 | if (ppc_md.get_boot_time) { |
767 | ts->tv_sec = ppc_md.get_boot_time() - timezone_offset; | |
768 | return; | |
769 | } | |
770 | } | |
771 | if (!ppc_md.get_rtc_time) { | |
772 | ts->tv_sec = 0; | |
773 | return; | |
aa3be5f3 | 774 | } |
f2783c15 | 775 | ppc_md.get_rtc_time(&tm); |
978d7eb3 | 776 | |
d4f587c6 MS |
777 | ts->tv_sec = mktime(tm.tm_year+1900, tm.tm_mon+1, tm.tm_mday, |
778 | tm.tm_hour, tm.tm_min, tm.tm_sec); | |
f2783c15 PM |
779 | } |
780 | ||
978d7eb3 BH |
781 | void read_persistent_clock(struct timespec *ts) |
782 | { | |
783 | __read_persistent_clock(ts); | |
784 | ||
785 | /* Sanitize it in case real time clock is set below EPOCH */ | |
786 | if (ts->tv_sec < 0) { | |
787 | ts->tv_sec = 0; | |
788 | ts->tv_nsec = 0; | |
789 | } | |
790 | ||
791 | } | |
792 | ||
4a4cfe38 | 793 | /* clocksource code */ |
8e19608e | 794 | static cycle_t rtc_read(struct clocksource *cs) |
4a4cfe38 TB |
795 | { |
796 | return (cycle_t)get_rtc(); | |
797 | } | |
798 | ||
8e19608e | 799 | static cycle_t timebase_read(struct clocksource *cs) |
4a4cfe38 TB |
800 | { |
801 | return (cycle_t)get_tb(); | |
802 | } | |
803 | ||
7615856e JS |
804 | void update_vsyscall(struct timespec *wall_time, struct timespec *wtm, |
805 | struct clocksource *clock, u32 mult) | |
4a4cfe38 | 806 | { |
b0797b60 | 807 | u64 new_tb_to_xs, new_stamp_xsec; |
47916be4 | 808 | u32 frac_sec; |
4a4cfe38 TB |
809 | |
810 | if (clock != &clocksource_timebase) | |
811 | return; | |
812 | ||
813 | /* Make userspace gettimeofday spin until we're done. */ | |
814 | ++vdso_data->tb_update_count; | |
815 | smp_mb(); | |
816 | ||
817 | /* XXX this assumes clock->shift == 22 */ | |
818 | /* 4611686018 ~= 2^(20+64-22) / 1e9 */ | |
b0797b60 | 819 | new_tb_to_xs = (u64) mult * 4611686018ULL; |
06d518e3 | 820 | new_stamp_xsec = (u64) wall_time->tv_nsec * XSEC_PER_SEC; |
b0797b60 | 821 | do_div(new_stamp_xsec, 1000000000); |
06d518e3 | 822 | new_stamp_xsec += (u64) wall_time->tv_sec * XSEC_PER_SEC; |
b0797b60 | 823 | |
47916be4 TG |
824 | BUG_ON(wall_time->tv_nsec >= NSEC_PER_SEC); |
825 | /* this is tv_nsec / 1e9 as a 0.32 fraction */ | |
826 | frac_sec = ((u64) wall_time->tv_nsec * 18446744073ULL) >> 32; | |
827 | ||
b0797b60 JS |
828 | /* |
829 | * tb_update_count is used to allow the userspace gettimeofday code | |
830 | * to assure itself that it sees a consistent view of the tb_to_xs and | |
831 | * stamp_xsec variables. It reads the tb_update_count, then reads | |
832 | * tb_to_xs and stamp_xsec and then reads tb_update_count again. If | |
833 | * the two values of tb_update_count match and are even then the | |
834 | * tb_to_xs and stamp_xsec values are consistent. If not, then it | |
835 | * loops back and reads them again until this criteria is met. | |
836 | * We expect the caller to have done the first increment of | |
837 | * vdso_data->tb_update_count already. | |
838 | */ | |
839 | vdso_data->tb_orig_stamp = clock->cycle_last; | |
840 | vdso_data->stamp_xsec = new_stamp_xsec; | |
841 | vdso_data->tb_to_xs = new_tb_to_xs; | |
7615856e JS |
842 | vdso_data->wtom_clock_sec = wtm->tv_sec; |
843 | vdso_data->wtom_clock_nsec = wtm->tv_nsec; | |
06d518e3 | 844 | vdso_data->stamp_xtime = *wall_time; |
0e469db8 | 845 | vdso_data->stamp_sec_fraction = frac_sec; |
b0797b60 JS |
846 | smp_wmb(); |
847 | ++(vdso_data->tb_update_count); | |
4a4cfe38 TB |
848 | } |
849 | ||
850 | void update_vsyscall_tz(void) | |
851 | { | |
852 | /* Make userspace gettimeofday spin until we're done. */ | |
853 | ++vdso_data->tb_update_count; | |
854 | smp_mb(); | |
855 | vdso_data->tz_minuteswest = sys_tz.tz_minuteswest; | |
856 | vdso_data->tz_dsttime = sys_tz.tz_dsttime; | |
857 | smp_mb(); | |
858 | ++vdso_data->tb_update_count; | |
859 | } | |
860 | ||
1c21a293 | 861 | static void __init clocksource_init(void) |
4a4cfe38 TB |
862 | { |
863 | struct clocksource *clock; | |
864 | ||
865 | if (__USE_RTC()) | |
866 | clock = &clocksource_rtc; | |
867 | else | |
868 | clock = &clocksource_timebase; | |
869 | ||
870 | clock->mult = clocksource_hz2mult(tb_ticks_per_sec, clock->shift); | |
871 | ||
872 | if (clocksource_register(clock)) { | |
873 | printk(KERN_ERR "clocksource: %s is already registered\n", | |
874 | clock->name); | |
875 | return; | |
876 | } | |
877 | ||
878 | printk(KERN_INFO "clocksource: %s mult[%x] shift[%d] registered\n", | |
879 | clock->name, clock->mult, clock->shift); | |
880 | } | |
881 | ||
d831d0b8 TB |
882 | static int decrementer_set_next_event(unsigned long evt, |
883 | struct clock_event_device *dev) | |
884 | { | |
6e6b44e8 | 885 | __get_cpu_var(decrementers).next_tb = get_tb_or_rtc() + evt; |
d831d0b8 TB |
886 | set_dec(evt); |
887 | return 0; | |
888 | } | |
889 | ||
890 | static void decrementer_set_mode(enum clock_event_mode mode, | |
891 | struct clock_event_device *dev) | |
892 | { | |
893 | if (mode != CLOCK_EVT_MODE_ONESHOT) | |
894 | decrementer_set_next_event(DECREMENTER_MAX, dev); | |
895 | } | |
896 | ||
3e7b4843 SR |
897 | static inline uint64_t div_sc64(unsigned long ticks, unsigned long nsec, |
898 | int shift) | |
899 | { | |
900 | uint64_t tmp = ((uint64_t)ticks) << shift; | |
901 | ||
902 | do_div(tmp, nsec); | |
903 | return tmp; | |
904 | } | |
905 | ||
8d165db1 AB |
906 | static void __init setup_clockevent_multiplier(unsigned long hz) |
907 | { | |
908 | u64 mult, shift = 32; | |
909 | ||
910 | while (1) { | |
3e7b4843 | 911 | mult = div_sc64(hz, NSEC_PER_SEC, shift); |
8d165db1 AB |
912 | if (mult && (mult >> 32UL) == 0UL) |
913 | break; | |
914 | ||
915 | shift--; | |
916 | } | |
917 | ||
918 | decrementer_clockevent.shift = shift; | |
919 | decrementer_clockevent.mult = mult; | |
920 | } | |
921 | ||
d831d0b8 TB |
922 | static void register_decrementer_clockevent(int cpu) |
923 | { | |
6e6b44e8 | 924 | struct clock_event_device *dec = &per_cpu(decrementers, cpu).event; |
d831d0b8 TB |
925 | |
926 | *dec = decrementer_clockevent; | |
320ab2b0 | 927 | dec->cpumask = cpumask_of(cpu); |
d831d0b8 | 928 | |
b919ee82 AB |
929 | printk_once(KERN_DEBUG "clockevent: %s mult[%x] shift[%d] cpu[%d]\n", |
930 | dec->name, dec->mult, dec->shift, cpu); | |
d831d0b8 TB |
931 | |
932 | clockevents_register_device(dec); | |
933 | } | |
934 | ||
c481887f | 935 | static void __init init_decrementer_clockevent(void) |
d831d0b8 TB |
936 | { |
937 | int cpu = smp_processor_id(); | |
938 | ||
8d165db1 | 939 | setup_clockevent_multiplier(ppc_tb_freq); |
d831d0b8 TB |
940 | decrementer_clockevent.max_delta_ns = |
941 | clockevent_delta2ns(DECREMENTER_MAX, &decrementer_clockevent); | |
43875cc0 PM |
942 | decrementer_clockevent.min_delta_ns = |
943 | clockevent_delta2ns(2, &decrementer_clockevent); | |
d831d0b8 TB |
944 | |
945 | register_decrementer_clockevent(cpu); | |
946 | } | |
947 | ||
948 | void secondary_cpu_time_init(void) | |
949 | { | |
77c0a700 BH |
950 | /* Start the decrementer on CPUs that have manual control |
951 | * such as BookE | |
952 | */ | |
953 | start_cpu_decrementer(); | |
954 | ||
d831d0b8 TB |
955 | /* FIME: Should make unrelatred change to move snapshot_timebase |
956 | * call here ! */ | |
957 | register_decrementer_clockevent(smp_processor_id()); | |
958 | } | |
959 | ||
f2783c15 | 960 | /* This function is only called on the boot processor */ |
1da177e4 LT |
961 | void __init time_init(void) |
962 | { | |
1da177e4 | 963 | struct div_result res; |
d75d68cf | 964 | u64 scale; |
f2783c15 PM |
965 | unsigned shift; |
966 | ||
96c44507 PM |
967 | if (__USE_RTC()) { |
968 | /* 601 processor: dec counts down by 128 every 128ns */ | |
969 | ppc_tb_freq = 1000000000; | |
96c44507 PM |
970 | } else { |
971 | /* Normal PowerPC with timebase register */ | |
972 | ppc_md.calibrate_decr(); | |
224ad80a | 973 | printk(KERN_DEBUG "time_init: decrementer frequency = %lu.%.6lu MHz\n", |
96c44507 | 974 | ppc_tb_freq / 1000000, ppc_tb_freq % 1000000); |
224ad80a | 975 | printk(KERN_DEBUG "time_init: processor frequency = %lu.%.6lu MHz\n", |
96c44507 | 976 | ppc_proc_freq / 1000000, ppc_proc_freq % 1000000); |
96c44507 | 977 | } |
374e99d4 PM |
978 | |
979 | tb_ticks_per_jiffy = ppc_tb_freq / HZ; | |
092b8f34 | 980 | tb_ticks_per_sec = ppc_tb_freq; |
374e99d4 | 981 | tb_ticks_per_usec = ppc_tb_freq / 1000000; |
c6622f63 | 982 | calc_cputime_factors(); |
a42548a1 | 983 | setup_cputime_one_jiffy(); |
092b8f34 | 984 | |
1da177e4 LT |
985 | /* |
986 | * Compute scale factor for sched_clock. | |
987 | * The calibrate_decr() function has set tb_ticks_per_sec, | |
988 | * which is the timebase frequency. | |
989 | * We compute 1e9 * 2^64 / tb_ticks_per_sec and interpret | |
990 | * the 128-bit result as a 64.64 fixed-point number. | |
991 | * We then shift that number right until it is less than 1.0, | |
992 | * giving us the scale factor and shift count to use in | |
993 | * sched_clock(). | |
994 | */ | |
995 | div128_by_32(1000000000, 0, tb_ticks_per_sec, &res); | |
996 | scale = res.result_low; | |
997 | for (shift = 0; res.result_high != 0; ++shift) { | |
998 | scale = (scale >> 1) | (res.result_high << 63); | |
999 | res.result_high >>= 1; | |
1000 | } | |
1001 | tb_to_ns_scale = scale; | |
1002 | tb_to_ns_shift = shift; | |
fc9069fe | 1003 | /* Save the current timebase to pretty up CONFIG_PRINTK_TIME */ |
c27da339 | 1004 | boot_tb = get_tb_or_rtc(); |
1da177e4 | 1005 | |
092b8f34 PM |
1006 | /* If platform provided a timezone (pmac), we correct the time */ |
1007 | if (timezone_offset) { | |
1008 | sys_tz.tz_minuteswest = -timezone_offset / 60; | |
1009 | sys_tz.tz_dsttime = 0; | |
092b8f34 PM |
1010 | } |
1011 | ||
a7f290da BH |
1012 | vdso_data->tb_update_count = 0; |
1013 | vdso_data->tb_ticks_per_sec = tb_ticks_per_sec; | |
1da177e4 | 1014 | |
77c0a700 BH |
1015 | /* Start the decrementer on CPUs that have manual control |
1016 | * such as BookE | |
1017 | */ | |
1018 | start_cpu_decrementer(); | |
1019 | ||
4a4cfe38 TB |
1020 | /* Register the clocksource, if we're not running on iSeries */ |
1021 | if (!firmware_has_feature(FW_FEATURE_ISERIES)) | |
1022 | clocksource_init(); | |
1023 | ||
d831d0b8 | 1024 | init_decrementer_clockevent(); |
1da177e4 LT |
1025 | } |
1026 | ||
1da177e4 | 1027 | |
1da177e4 LT |
1028 | #define FEBRUARY 2 |
1029 | #define STARTOFTIME 1970 | |
1030 | #define SECDAY 86400L | |
1031 | #define SECYR (SECDAY * 365) | |
f2783c15 PM |
1032 | #define leapyear(year) ((year) % 4 == 0 && \ |
1033 | ((year) % 100 != 0 || (year) % 400 == 0)) | |
1da177e4 LT |
1034 | #define days_in_year(a) (leapyear(a) ? 366 : 365) |
1035 | #define days_in_month(a) (month_days[(a) - 1]) | |
1036 | ||
1037 | static int month_days[12] = { | |
1038 | 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 | |
1039 | }; | |
1040 | ||
1041 | /* | |
1042 | * This only works for the Gregorian calendar - i.e. after 1752 (in the UK) | |
1043 | */ | |
1044 | void GregorianDay(struct rtc_time * tm) | |
1045 | { | |
1046 | int leapsToDate; | |
1047 | int lastYear; | |
1048 | int day; | |
1049 | int MonthOffset[] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 }; | |
1050 | ||
f2783c15 | 1051 | lastYear = tm->tm_year - 1; |
1da177e4 LT |
1052 | |
1053 | /* | |
1054 | * Number of leap corrections to apply up to end of last year | |
1055 | */ | |
f2783c15 | 1056 | leapsToDate = lastYear / 4 - lastYear / 100 + lastYear / 400; |
1da177e4 LT |
1057 | |
1058 | /* | |
1059 | * This year is a leap year if it is divisible by 4 except when it is | |
1060 | * divisible by 100 unless it is divisible by 400 | |
1061 | * | |
f2783c15 | 1062 | * e.g. 1904 was a leap year, 1900 was not, 1996 is, and 2000 was |
1da177e4 | 1063 | */ |
f2783c15 | 1064 | day = tm->tm_mon > 2 && leapyear(tm->tm_year); |
1da177e4 LT |
1065 | |
1066 | day += lastYear*365 + leapsToDate + MonthOffset[tm->tm_mon-1] + | |
1067 | tm->tm_mday; | |
1068 | ||
f2783c15 | 1069 | tm->tm_wday = day % 7; |
1da177e4 LT |
1070 | } |
1071 | ||
1072 | void to_tm(int tim, struct rtc_time * tm) | |
1073 | { | |
1074 | register int i; | |
1075 | register long hms, day; | |
1076 | ||
1077 | day = tim / SECDAY; | |
1078 | hms = tim % SECDAY; | |
1079 | ||
1080 | /* Hours, minutes, seconds are easy */ | |
1081 | tm->tm_hour = hms / 3600; | |
1082 | tm->tm_min = (hms % 3600) / 60; | |
1083 | tm->tm_sec = (hms % 3600) % 60; | |
1084 | ||
1085 | /* Number of years in days */ | |
1086 | for (i = STARTOFTIME; day >= days_in_year(i); i++) | |
1087 | day -= days_in_year(i); | |
1088 | tm->tm_year = i; | |
1089 | ||
1090 | /* Number of months in days left */ | |
1091 | if (leapyear(tm->tm_year)) | |
1092 | days_in_month(FEBRUARY) = 29; | |
1093 | for (i = 1; day >= days_in_month(i); i++) | |
1094 | day -= days_in_month(i); | |
1095 | days_in_month(FEBRUARY) = 28; | |
1096 | tm->tm_mon = i; | |
1097 | ||
1098 | /* Days are what is left over (+1) from all that. */ | |
1099 | tm->tm_mday = day + 1; | |
1100 | ||
1101 | /* | |
1102 | * Determine the day of week | |
1103 | */ | |
1104 | GregorianDay(tm); | |
1105 | } | |
1106 | ||
1da177e4 LT |
1107 | /* |
1108 | * Divide a 128-bit dividend by a 32-bit divisor, leaving a 128 bit | |
1109 | * result. | |
1110 | */ | |
f2783c15 PM |
1111 | void div128_by_32(u64 dividend_high, u64 dividend_low, |
1112 | unsigned divisor, struct div_result *dr) | |
1da177e4 | 1113 | { |
f2783c15 PM |
1114 | unsigned long a, b, c, d; |
1115 | unsigned long w, x, y, z; | |
1116 | u64 ra, rb, rc; | |
1da177e4 LT |
1117 | |
1118 | a = dividend_high >> 32; | |
1119 | b = dividend_high & 0xffffffff; | |
1120 | c = dividend_low >> 32; | |
1121 | d = dividend_low & 0xffffffff; | |
1122 | ||
f2783c15 PM |
1123 | w = a / divisor; |
1124 | ra = ((u64)(a - (w * divisor)) << 32) + b; | |
1125 | ||
f2783c15 PM |
1126 | rb = ((u64) do_div(ra, divisor) << 32) + c; |
1127 | x = ra; | |
1da177e4 | 1128 | |
f2783c15 PM |
1129 | rc = ((u64) do_div(rb, divisor) << 32) + d; |
1130 | y = rb; | |
1131 | ||
1132 | do_div(rc, divisor); | |
1133 | z = rc; | |
1da177e4 | 1134 | |
f2783c15 PM |
1135 | dr->result_high = ((u64)w << 32) + x; |
1136 | dr->result_low = ((u64)y << 32) + z; | |
1da177e4 LT |
1137 | |
1138 | } | |
bcd68a70 | 1139 | |
177996e6 BH |
1140 | /* We don't need to calibrate delay, we use the CPU timebase for that */ |
1141 | void calibrate_delay(void) | |
1142 | { | |
1143 | /* Some generic code (such as spinlock debug) use loops_per_jiffy | |
1144 | * as the number of __delay(1) in a jiffy, so make it so | |
1145 | */ | |
1146 | loops_per_jiffy = tb_ticks_per_jiffy; | |
1147 | } | |
1148 | ||
bcd68a70 GU |
1149 | static int __init rtc_init(void) |
1150 | { | |
1151 | struct platform_device *pdev; | |
1152 | ||
1153 | if (!ppc_md.get_rtc_time) | |
1154 | return -ENODEV; | |
1155 | ||
1156 | pdev = platform_device_register_simple("rtc-generic", -1, NULL, 0); | |
1157 | if (IS_ERR(pdev)) | |
1158 | return PTR_ERR(pdev); | |
1159 | ||
1160 | return 0; | |
1161 | } | |
1162 | ||
1163 | module_init(rtc_init); |