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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> |
7f92bc56 | 58 | #include <linux/suspend.h> |
169047f4 | 59 | #include <linux/rtc.h> |
6795b85c | 60 | #include <asm/trace.h> |
1da177e4 | 61 | |
1da177e4 LT |
62 | #include <asm/io.h> |
63 | #include <asm/processor.h> | |
64 | #include <asm/nvram.h> | |
65 | #include <asm/cache.h> | |
66 | #include <asm/machdep.h> | |
1da177e4 LT |
67 | #include <asm/uaccess.h> |
68 | #include <asm/time.h> | |
1da177e4 | 69 | #include <asm/prom.h> |
f2783c15 PM |
70 | #include <asm/irq.h> |
71 | #include <asm/div64.h> | |
2249ca9d | 72 | #include <asm/smp.h> |
a7f290da | 73 | #include <asm/vdso_datapage.h> |
1ababe11 | 74 | #include <asm/firmware.h> |
06b8e878 | 75 | #include <asm/cputime.h> |
1da177e4 | 76 | |
4a4cfe38 TB |
77 | /* powerpc clocksource/clockevent code */ |
78 | ||
d831d0b8 | 79 | #include <linux/clockchips.h> |
189374ae | 80 | #include <linux/timekeeper_internal.h> |
4a4cfe38 | 81 | |
8e19608e | 82 | static cycle_t rtc_read(struct clocksource *); |
4a4cfe38 TB |
83 | static struct clocksource clocksource_rtc = { |
84 | .name = "rtc", | |
85 | .rating = 400, | |
86 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | |
87 | .mask = CLOCKSOURCE_MASK(64), | |
4a4cfe38 TB |
88 | .read = rtc_read, |
89 | }; | |
90 | ||
8e19608e | 91 | static cycle_t timebase_read(struct clocksource *); |
4a4cfe38 TB |
92 | static struct clocksource clocksource_timebase = { |
93 | .name = "timebase", | |
94 | .rating = 400, | |
95 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | |
96 | .mask = CLOCKSOURCE_MASK(64), | |
4a4cfe38 TB |
97 | .read = timebase_read, |
98 | }; | |
99 | ||
79901024 OH |
100 | #define DECREMENTER_DEFAULT_MAX 0x7FFFFFFF |
101 | u64 decrementer_max = DECREMENTER_DEFAULT_MAX; | |
d831d0b8 TB |
102 | |
103 | static int decrementer_set_next_event(unsigned long evt, | |
104 | struct clock_event_device *dev); | |
37a13e78 | 105 | static int decrementer_shutdown(struct clock_event_device *evt); |
d831d0b8 | 106 | |
6e35994d | 107 | struct clock_event_device decrementer_clockevent = { |
37a13e78 VK |
108 | .name = "decrementer", |
109 | .rating = 200, | |
110 | .irq = 0, | |
111 | .set_next_event = decrementer_set_next_event, | |
112 | .set_state_shutdown = decrementer_shutdown, | |
113 | .tick_resume = decrementer_shutdown, | |
114 | .features = CLOCK_EVT_FEAT_ONESHOT | | |
115 | CLOCK_EVT_FEAT_C3STOP, | |
d831d0b8 | 116 | }; |
6e35994d | 117 | EXPORT_SYMBOL(decrementer_clockevent); |
d831d0b8 | 118 | |
7df10275 AB |
119 | DEFINE_PER_CPU(u64, decrementers_next_tb); |
120 | static DEFINE_PER_CPU(struct clock_event_device, decrementers); | |
d831d0b8 | 121 | |
1da177e4 LT |
122 | #define XSEC_PER_SEC (1024*1024) |
123 | ||
f2783c15 PM |
124 | #ifdef CONFIG_PPC64 |
125 | #define SCALE_XSEC(xsec, max) (((xsec) * max) / XSEC_PER_SEC) | |
126 | #else | |
127 | /* compute ((xsec << 12) * max) >> 32 */ | |
128 | #define SCALE_XSEC(xsec, max) mulhwu((xsec) << 12, max) | |
129 | #endif | |
130 | ||
1da177e4 LT |
131 | unsigned long tb_ticks_per_jiffy; |
132 | unsigned long tb_ticks_per_usec = 100; /* sane default */ | |
133 | EXPORT_SYMBOL(tb_ticks_per_usec); | |
134 | unsigned long tb_ticks_per_sec; | |
2cf82c02 | 135 | EXPORT_SYMBOL(tb_ticks_per_sec); /* for cputime_t conversions */ |
092b8f34 | 136 | |
1da177e4 | 137 | DEFINE_SPINLOCK(rtc_lock); |
6ae3db11 | 138 | EXPORT_SYMBOL_GPL(rtc_lock); |
1da177e4 | 139 | |
fc9069fe TB |
140 | static u64 tb_to_ns_scale __read_mostly; |
141 | static unsigned tb_to_ns_shift __read_mostly; | |
364a1246 | 142 | static u64 boot_tb __read_mostly; |
1da177e4 | 143 | |
1da177e4 | 144 | extern struct timezone sys_tz; |
f2783c15 | 145 | static long timezone_offset; |
1da177e4 | 146 | |
10f7e7c1 | 147 | unsigned long ppc_proc_freq; |
55ec2fca | 148 | EXPORT_SYMBOL_GPL(ppc_proc_freq); |
10f7e7c1 | 149 | unsigned long ppc_tb_freq; |
55ec2fca | 150 | EXPORT_SYMBOL_GPL(ppc_tb_freq); |
96c44507 | 151 | |
abf917cd | 152 | #ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE |
c6622f63 PM |
153 | /* |
154 | * Factors for converting from cputime_t (timebase ticks) to | |
9f5072d4 | 155 | * jiffies, microseconds, seconds, and clock_t (1/USER_HZ seconds). |
c6622f63 PM |
156 | * These are all stored as 0.64 fixed-point binary fractions. |
157 | */ | |
158 | u64 __cputime_jiffies_factor; | |
2cf82c02 | 159 | EXPORT_SYMBOL(__cputime_jiffies_factor); |
9f5072d4 AS |
160 | u64 __cputime_usec_factor; |
161 | EXPORT_SYMBOL(__cputime_usec_factor); | |
c6622f63 | 162 | u64 __cputime_sec_factor; |
2cf82c02 | 163 | EXPORT_SYMBOL(__cputime_sec_factor); |
c6622f63 | 164 | u64 __cputime_clockt_factor; |
2cf82c02 | 165 | EXPORT_SYMBOL(__cputime_clockt_factor); |
06b8e878 MN |
166 | DEFINE_PER_CPU(unsigned long, cputime_last_delta); |
167 | DEFINE_PER_CPU(unsigned long, cputime_scaled_last_delta); | |
c6622f63 | 168 | |
a42548a1 SG |
169 | cputime_t cputime_one_jiffy; |
170 | ||
c223c903 | 171 | #ifdef CONFIG_PPC_SPLPAR |
872e439a | 172 | void (*dtl_consumer)(struct dtl_entry *, u64); |
c223c903 CL |
173 | #endif |
174 | ||
175 | #ifdef CONFIG_PPC64 | |
176 | #define get_accounting(tsk) (&get_paca()->accounting) | |
177 | #else | |
178 | #define get_accounting(tsk) (&task_thread_info(tsk)->accounting) | |
179 | #endif | |
872e439a | 180 | |
c6622f63 PM |
181 | static void calc_cputime_factors(void) |
182 | { | |
183 | struct div_result res; | |
184 | ||
185 | div128_by_32(HZ, 0, tb_ticks_per_sec, &res); | |
186 | __cputime_jiffies_factor = res.result_low; | |
9f5072d4 AS |
187 | div128_by_32(1000000, 0, tb_ticks_per_sec, &res); |
188 | __cputime_usec_factor = res.result_low; | |
c6622f63 PM |
189 | div128_by_32(1, 0, tb_ticks_per_sec, &res); |
190 | __cputime_sec_factor = res.result_low; | |
191 | div128_by_32(USER_HZ, 0, tb_ticks_per_sec, &res); | |
192 | __cputime_clockt_factor = res.result_low; | |
193 | } | |
194 | ||
195 | /* | |
cf9efce0 PM |
196 | * Read the SPURR on systems that have it, otherwise the PURR, |
197 | * or if that doesn't exist return the timebase value passed in. | |
c6622f63 | 198 | */ |
c223c903 | 199 | static unsigned long read_spurr(unsigned long tb) |
c6622f63 | 200 | { |
cf9efce0 PM |
201 | if (cpu_has_feature(CPU_FTR_SPURR)) |
202 | return mfspr(SPRN_SPURR); | |
c6622f63 PM |
203 | if (cpu_has_feature(CPU_FTR_PURR)) |
204 | return mfspr(SPRN_PURR); | |
cf9efce0 | 205 | return tb; |
c6622f63 PM |
206 | } |
207 | ||
cf9efce0 PM |
208 | #ifdef CONFIG_PPC_SPLPAR |
209 | ||
4603ac18 | 210 | /* |
cf9efce0 PM |
211 | * Scan the dispatch trace log and count up the stolen time. |
212 | * Should be called with interrupts disabled. | |
4603ac18 | 213 | */ |
cf9efce0 | 214 | static u64 scan_dispatch_log(u64 stop_tb) |
4603ac18 | 215 | { |
872e439a | 216 | u64 i = local_paca->dtl_ridx; |
cf9efce0 PM |
217 | struct dtl_entry *dtl = local_paca->dtl_curr; |
218 | struct dtl_entry *dtl_end = local_paca->dispatch_log_end; | |
219 | struct lppaca *vpa = local_paca->lppaca_ptr; | |
220 | u64 tb_delta; | |
221 | u64 stolen = 0; | |
222 | u64 dtb; | |
223 | ||
84ffae55 AB |
224 | if (!dtl) |
225 | return 0; | |
226 | ||
7ffcf8ec | 227 | if (i == be64_to_cpu(vpa->dtl_idx)) |
cf9efce0 | 228 | return 0; |
7ffcf8ec | 229 | while (i < be64_to_cpu(vpa->dtl_idx)) { |
7ffcf8ec AB |
230 | dtb = be64_to_cpu(dtl->timebase); |
231 | tb_delta = be32_to_cpu(dtl->enqueue_to_dispatch_time) + | |
232 | be32_to_cpu(dtl->ready_to_enqueue_time); | |
cf9efce0 | 233 | barrier(); |
7ffcf8ec | 234 | if (i + N_DISPATCH_LOG < be64_to_cpu(vpa->dtl_idx)) { |
cf9efce0 | 235 | /* buffer has overflowed */ |
7ffcf8ec | 236 | i = be64_to_cpu(vpa->dtl_idx) - N_DISPATCH_LOG; |
cf9efce0 PM |
237 | dtl = local_paca->dispatch_log + (i % N_DISPATCH_LOG); |
238 | continue; | |
239 | } | |
240 | if (dtb > stop_tb) | |
241 | break; | |
84b07386 AB |
242 | if (dtl_consumer) |
243 | dtl_consumer(dtl, i); | |
cf9efce0 PM |
244 | stolen += tb_delta; |
245 | ++i; | |
246 | ++dtl; | |
247 | if (dtl == dtl_end) | |
248 | dtl = local_paca->dispatch_log; | |
249 | } | |
250 | local_paca->dtl_ridx = i; | |
251 | local_paca->dtl_curr = dtl; | |
252 | return stolen; | |
4603ac18 MN |
253 | } |
254 | ||
cf9efce0 PM |
255 | /* |
256 | * Accumulate stolen time by scanning the dispatch trace log. | |
257 | * Called on entry from user mode. | |
258 | */ | |
259 | void accumulate_stolen_time(void) | |
260 | { | |
261 | u64 sst, ust; | |
b18ae08d | 262 | u8 save_soft_enabled = local_paca->soft_enabled; |
c223c903 | 263 | struct cpu_accounting_data *acct = &local_paca->accounting; |
b18ae08d TH |
264 | |
265 | /* We are called early in the exception entry, before | |
266 | * soft/hard_enabled are sync'ed to the expected state | |
267 | * for the exception. We are hard disabled but the PACA | |
268 | * needs to reflect that so various debug stuff doesn't | |
269 | * complain | |
270 | */ | |
271 | local_paca->soft_enabled = 0; | |
b18ae08d | 272 | |
c223c903 CL |
273 | sst = scan_dispatch_log(acct->starttime_user); |
274 | ust = scan_dispatch_log(acct->starttime); | |
275 | acct->system_time -= sst; | |
276 | acct->user_time -= ust; | |
b18ae08d TH |
277 | local_paca->stolen_time += ust + sst; |
278 | ||
279 | local_paca->soft_enabled = save_soft_enabled; | |
cf9efce0 PM |
280 | } |
281 | ||
282 | static inline u64 calculate_stolen_time(u64 stop_tb) | |
283 | { | |
284 | u64 stolen = 0; | |
285 | ||
7ffcf8ec | 286 | if (get_paca()->dtl_ridx != be64_to_cpu(get_lppaca()->dtl_idx)) { |
cf9efce0 | 287 | stolen = scan_dispatch_log(stop_tb); |
c223c903 | 288 | get_paca()->accounting.system_time -= stolen; |
cf9efce0 PM |
289 | } |
290 | ||
291 | stolen += get_paca()->stolen_time; | |
292 | get_paca()->stolen_time = 0; | |
293 | return stolen; | |
4603ac18 MN |
294 | } |
295 | ||
cf9efce0 PM |
296 | #else /* CONFIG_PPC_SPLPAR */ |
297 | static inline u64 calculate_stolen_time(u64 stop_tb) | |
298 | { | |
299 | return 0; | |
300 | } | |
301 | ||
302 | #endif /* CONFIG_PPC_SPLPAR */ | |
303 | ||
c6622f63 PM |
304 | /* |
305 | * Account time for a transition between system, hard irq | |
306 | * or soft irq state. | |
307 | */ | |
c223c903 CL |
308 | static unsigned long vtime_delta(struct task_struct *tsk, |
309 | unsigned long *sys_scaled, | |
310 | unsigned long *stolen) | |
c6622f63 | 311 | { |
c223c903 CL |
312 | unsigned long now, nowscaled, deltascaled; |
313 | unsigned long udelta, delta, user_scaled; | |
314 | struct cpu_accounting_data *acct = get_accounting(tsk); | |
c6622f63 | 315 | |
1b2852b1 FW |
316 | WARN_ON_ONCE(!irqs_disabled()); |
317 | ||
cf9efce0 | 318 | now = mftb(); |
4603ac18 | 319 | nowscaled = read_spurr(now); |
c223c903 CL |
320 | acct->system_time += now - acct->starttime; |
321 | acct->starttime = now; | |
322 | deltascaled = nowscaled - acct->startspurr; | |
323 | acct->startspurr = nowscaled; | |
cf9efce0 | 324 | |
a7e1a9e3 | 325 | *stolen = calculate_stolen_time(now); |
cf9efce0 | 326 | |
c223c903 CL |
327 | delta = acct->system_time; |
328 | acct->system_time = 0; | |
329 | udelta = acct->user_time - acct->utime_sspurr; | |
330 | acct->utime_sspurr = acct->user_time; | |
cf9efce0 PM |
331 | |
332 | /* | |
333 | * Because we don't read the SPURR on every kernel entry/exit, | |
334 | * deltascaled includes both user and system SPURR ticks. | |
335 | * Apportion these ticks to system SPURR ticks and user | |
336 | * SPURR ticks in the same ratio as the system time (delta) | |
337 | * and user time (udelta) values obtained from the timebase | |
338 | * over the same interval. The system ticks get accounted here; | |
339 | * the user ticks get saved up in paca->user_time_scaled to be | |
340 | * used by account_process_tick. | |
341 | */ | |
a7e1a9e3 | 342 | *sys_scaled = delta; |
cf9efce0 PM |
343 | user_scaled = udelta; |
344 | if (deltascaled != delta + udelta) { | |
345 | if (udelta) { | |
a7e1a9e3 FW |
346 | *sys_scaled = deltascaled * delta / (delta + udelta); |
347 | user_scaled = deltascaled - *sys_scaled; | |
cf9efce0 | 348 | } else { |
a7e1a9e3 | 349 | *sys_scaled = deltascaled; |
cf9efce0 PM |
350 | } |
351 | } | |
c223c903 | 352 | acct->user_time_scaled += user_scaled; |
cf9efce0 | 353 | |
a7e1a9e3 FW |
354 | return delta; |
355 | } | |
356 | ||
fd25b4c2 | 357 | void vtime_account_system(struct task_struct *tsk) |
a7e1a9e3 | 358 | { |
c223c903 | 359 | unsigned long delta, sys_scaled, stolen; |
a7e1a9e3 FW |
360 | |
361 | delta = vtime_delta(tsk, &sys_scaled, &stolen); | |
362 | account_system_time(tsk, 0, delta, sys_scaled); | |
363 | if (stolen) | |
364 | account_steal_time(stolen); | |
365 | } | |
c11f11fc | 366 | EXPORT_SYMBOL_GPL(vtime_account_system); |
a7e1a9e3 | 367 | |
fd25b4c2 | 368 | void vtime_account_idle(struct task_struct *tsk) |
a7e1a9e3 | 369 | { |
c223c903 | 370 | unsigned long delta, sys_scaled, stolen; |
a7e1a9e3 FW |
371 | |
372 | delta = vtime_delta(tsk, &sys_scaled, &stolen); | |
373 | account_idle_time(delta + stolen); | |
c6622f63 PM |
374 | } |
375 | ||
376 | /* | |
bcebdf84 FW |
377 | * Transfer the user time accumulated in the paca |
378 | * by the exception entry and exit code to the generic | |
379 | * process user time records. | |
c6622f63 | 380 | * Must be called with interrupts disabled. |
bcebdf84 FW |
381 | * Assumes that vtime_account_system/idle() has been called |
382 | * recently (i.e. since the last entry from usermode) so that | |
cf9efce0 | 383 | * get_paca()->user_time_scaled is up to date. |
c6622f63 | 384 | */ |
bcebdf84 | 385 | void vtime_account_user(struct task_struct *tsk) |
c6622f63 | 386 | { |
4603ac18 | 387 | cputime_t utime, utimescaled; |
c223c903 | 388 | struct cpu_accounting_data *acct = get_accounting(tsk); |
c6622f63 | 389 | |
c223c903 CL |
390 | utime = acct->user_time; |
391 | utimescaled = acct->user_time_scaled; | |
392 | acct->user_time = 0; | |
393 | acct->user_time_scaled = 0; | |
394 | acct->utime_sspurr = 0; | |
457533a7 | 395 | account_user_time(tsk, utime, utimescaled); |
c6622f63 PM |
396 | } |
397 | ||
c223c903 CL |
398 | #ifdef CONFIG_PPC32 |
399 | /* | |
400 | * Called from the context switch with interrupts disabled, to charge all | |
401 | * accumulated times to the current process, and to prepare accounting on | |
402 | * the next process. | |
403 | */ | |
404 | void arch_vtime_task_switch(struct task_struct *prev) | |
405 | { | |
406 | struct cpu_accounting_data *acct = get_accounting(current); | |
407 | ||
408 | acct->starttime = get_accounting(prev)->starttime; | |
409 | acct->system_time = 0; | |
410 | acct->user_time = 0; | |
411 | } | |
412 | #endif /* CONFIG_PPC32 */ | |
413 | ||
abf917cd | 414 | #else /* ! CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ |
c6622f63 | 415 | #define calc_cputime_factors() |
c6622f63 PM |
416 | #endif |
417 | ||
6defa38b PM |
418 | void __delay(unsigned long loops) |
419 | { | |
420 | unsigned long start; | |
421 | int diff; | |
422 | ||
423 | if (__USE_RTC()) { | |
424 | start = get_rtcl(); | |
425 | do { | |
426 | /* the RTCL register wraps at 1000000000 */ | |
427 | diff = get_rtcl() - start; | |
428 | if (diff < 0) | |
429 | diff += 1000000000; | |
430 | } while (diff < loops); | |
431 | } else { | |
432 | start = get_tbl(); | |
433 | while (get_tbl() - start < loops) | |
434 | HMT_low(); | |
435 | HMT_medium(); | |
436 | } | |
437 | } | |
438 | EXPORT_SYMBOL(__delay); | |
439 | ||
440 | void udelay(unsigned long usecs) | |
441 | { | |
442 | __delay(tb_ticks_per_usec * usecs); | |
443 | } | |
444 | EXPORT_SYMBOL(udelay); | |
445 | ||
1da177e4 LT |
446 | #ifdef CONFIG_SMP |
447 | unsigned long profile_pc(struct pt_regs *regs) | |
448 | { | |
449 | unsigned long pc = instruction_pointer(regs); | |
450 | ||
451 | if (in_lock_functions(pc)) | |
452 | return regs->link; | |
453 | ||
454 | return pc; | |
455 | } | |
456 | EXPORT_SYMBOL(profile_pc); | |
457 | #endif | |
458 | ||
e360adbe | 459 | #ifdef CONFIG_IRQ_WORK |
105988c0 | 460 | |
0fe1ac48 PM |
461 | /* |
462 | * 64-bit uses a byte in the PACA, 32-bit uses a per-cpu variable... | |
463 | */ | |
464 | #ifdef CONFIG_PPC64 | |
e360adbe | 465 | static inline unsigned long test_irq_work_pending(void) |
105988c0 | 466 | { |
0fe1ac48 PM |
467 | unsigned long x; |
468 | ||
469 | asm volatile("lbz %0,%1(13)" | |
470 | : "=r" (x) | |
e360adbe | 471 | : "i" (offsetof(struct paca_struct, irq_work_pending))); |
0fe1ac48 PM |
472 | return x; |
473 | } | |
474 | ||
e360adbe | 475 | static inline void set_irq_work_pending_flag(void) |
0fe1ac48 PM |
476 | { |
477 | asm volatile("stb %0,%1(13)" : : | |
478 | "r" (1), | |
e360adbe | 479 | "i" (offsetof(struct paca_struct, irq_work_pending))); |
0fe1ac48 PM |
480 | } |
481 | ||
e360adbe | 482 | static inline void clear_irq_work_pending(void) |
0fe1ac48 PM |
483 | { |
484 | asm volatile("stb %0,%1(13)" : : | |
485 | "r" (0), | |
e360adbe | 486 | "i" (offsetof(struct paca_struct, irq_work_pending))); |
105988c0 PM |
487 | } |
488 | ||
0fe1ac48 PM |
489 | #else /* 32-bit */ |
490 | ||
e360adbe | 491 | DEFINE_PER_CPU(u8, irq_work_pending); |
0fe1ac48 | 492 | |
69111bac CL |
493 | #define set_irq_work_pending_flag() __this_cpu_write(irq_work_pending, 1) |
494 | #define test_irq_work_pending() __this_cpu_read(irq_work_pending) | |
495 | #define clear_irq_work_pending() __this_cpu_write(irq_work_pending, 0) | |
105988c0 | 496 | |
0fe1ac48 PM |
497 | #endif /* 32 vs 64 bit */ |
498 | ||
4f8b50bb | 499 | void arch_irq_work_raise(void) |
0fe1ac48 PM |
500 | { |
501 | preempt_disable(); | |
e360adbe | 502 | set_irq_work_pending_flag(); |
0fe1ac48 PM |
503 | set_dec(1); |
504 | preempt_enable(); | |
505 | } | |
506 | ||
e360adbe | 507 | #else /* CONFIG_IRQ_WORK */ |
105988c0 | 508 | |
e360adbe PZ |
509 | #define test_irq_work_pending() 0 |
510 | #define clear_irq_work_pending() | |
105988c0 | 511 | |
e360adbe | 512 | #endif /* CONFIG_IRQ_WORK */ |
105988c0 | 513 | |
e51df2c1 | 514 | static void __timer_interrupt(void) |
1b783955 PM |
515 | { |
516 | struct pt_regs *regs = get_irq_regs(); | |
69111bac CL |
517 | u64 *next_tb = this_cpu_ptr(&decrementers_next_tb); |
518 | struct clock_event_device *evt = this_cpu_ptr(&decrementers); | |
1b783955 PM |
519 | u64 now; |
520 | ||
521 | trace_timer_interrupt_entry(regs); | |
522 | ||
523 | if (test_irq_work_pending()) { | |
524 | clear_irq_work_pending(); | |
525 | irq_work_run(); | |
526 | } | |
527 | ||
528 | now = get_tb_or_rtc(); | |
529 | if (now >= *next_tb) { | |
530 | *next_tb = ~(u64)0; | |
531 | if (evt->event_handler) | |
532 | evt->event_handler(evt); | |
69111bac | 533 | __this_cpu_inc(irq_stat.timer_irqs_event); |
1b783955 PM |
534 | } else { |
535 | now = *next_tb - now; | |
79901024 OH |
536 | if (now <= decrementer_max) |
537 | set_dec(now); | |
1b783955 PM |
538 | /* We may have raced with new irq work */ |
539 | if (test_irq_work_pending()) | |
540 | set_dec(1); | |
69111bac | 541 | __this_cpu_inc(irq_stat.timer_irqs_others); |
1b783955 PM |
542 | } |
543 | ||
544 | #ifdef CONFIG_PPC64 | |
545 | /* collect purr register values often, for accurate calculations */ | |
546 | if (firmware_has_feature(FW_FEATURE_SPLPAR)) { | |
69111bac | 547 | struct cpu_usage *cu = this_cpu_ptr(&cpu_usage_array); |
1b783955 PM |
548 | cu->current_tb = mfspr(SPRN_PURR); |
549 | } | |
550 | #endif | |
551 | ||
552 | trace_timer_interrupt_exit(regs); | |
553 | } | |
554 | ||
1da177e4 LT |
555 | /* |
556 | * timer_interrupt - gets called when the decrementer overflows, | |
557 | * with interrupts disabled. | |
558 | */ | |
c7aeffc4 | 559 | void timer_interrupt(struct pt_regs * regs) |
1da177e4 | 560 | { |
7d12e780 | 561 | struct pt_regs *old_regs; |
69111bac | 562 | u64 *next_tb = this_cpu_ptr(&decrementers_next_tb); |
d831d0b8 | 563 | |
963e5d3b BH |
564 | /* Ensure a positive value is written to the decrementer, or else |
565 | * some CPUs will continue to take decrementer exceptions. | |
566 | */ | |
79901024 | 567 | set_dec(decrementer_max); |
963e5d3b BH |
568 | |
569 | /* Some implementations of hotplug will get timer interrupts while | |
689dfa89 TC |
570 | * offline, just ignore these and we also need to set |
571 | * decrementers_next_tb as MAX to make sure __check_irq_replay | |
572 | * don't replay timer interrupt when return, otherwise we'll trap | |
573 | * here infinitely :( | |
963e5d3b | 574 | */ |
689dfa89 TC |
575 | if (!cpu_online(smp_processor_id())) { |
576 | *next_tb = ~(u64)0; | |
963e5d3b | 577 | return; |
689dfa89 | 578 | } |
963e5d3b | 579 | |
7230c564 BH |
580 | /* Conditionally hard-enable interrupts now that the DEC has been |
581 | * bumped to its maximum value | |
582 | */ | |
583 | may_hard_irq_enable(); | |
584 | ||
89713ed1 | 585 | |
6e0fdf9a | 586 | #if defined(CONFIG_PPC32) && defined(CONFIG_PPC_PMAC) |
f2783c15 PM |
587 | if (atomic_read(&ppc_n_lost_interrupts) != 0) |
588 | do_IRQ(regs); | |
589 | #endif | |
1da177e4 | 590 | |
7d12e780 | 591 | old_regs = set_irq_regs(regs); |
1da177e4 LT |
592 | irq_enter(); |
593 | ||
1b783955 | 594 | __timer_interrupt(); |
1da177e4 | 595 | irq_exit(); |
7d12e780 | 596 | set_irq_regs(old_regs); |
1da177e4 LT |
597 | } |
598 | ||
dabe859e PM |
599 | /* |
600 | * Hypervisor decrementer interrupts shouldn't occur but are sometimes | |
601 | * left pending on exit from a KVM guest. We don't need to do anything | |
602 | * to clear them, as they are edge-triggered. | |
603 | */ | |
604 | void hdec_interrupt(struct pt_regs *regs) | |
605 | { | |
606 | } | |
607 | ||
7ac5dde9 | 608 | #ifdef CONFIG_SUSPEND |
d75d68cf | 609 | static void generic_suspend_disable_irqs(void) |
7ac5dde9 | 610 | { |
7ac5dde9 SW |
611 | /* Disable the decrementer, so that it doesn't interfere |
612 | * with suspending. | |
613 | */ | |
614 | ||
79901024 | 615 | set_dec(decrementer_max); |
7ac5dde9 | 616 | local_irq_disable(); |
79901024 | 617 | set_dec(decrementer_max); |
7ac5dde9 SW |
618 | } |
619 | ||
d75d68cf | 620 | static void generic_suspend_enable_irqs(void) |
7ac5dde9 | 621 | { |
7ac5dde9 | 622 | local_irq_enable(); |
7ac5dde9 SW |
623 | } |
624 | ||
625 | /* Overrides the weak version in kernel/power/main.c */ | |
626 | void arch_suspend_disable_irqs(void) | |
627 | { | |
628 | if (ppc_md.suspend_disable_irqs) | |
629 | ppc_md.suspend_disable_irqs(); | |
630 | generic_suspend_disable_irqs(); | |
631 | } | |
632 | ||
633 | /* Overrides the weak version in kernel/power/main.c */ | |
634 | void arch_suspend_enable_irqs(void) | |
635 | { | |
636 | generic_suspend_enable_irqs(); | |
637 | if (ppc_md.suspend_enable_irqs) | |
638 | ppc_md.suspend_enable_irqs(); | |
639 | } | |
640 | #endif | |
641 | ||
b6c295df PM |
642 | unsigned long long tb_to_ns(unsigned long long ticks) |
643 | { | |
644 | return mulhdu(ticks, tb_to_ns_scale) << tb_to_ns_shift; | |
645 | } | |
646 | EXPORT_SYMBOL_GPL(tb_to_ns); | |
647 | ||
1da177e4 LT |
648 | /* |
649 | * Scheduler clock - returns current time in nanosec units. | |
650 | * | |
651 | * Note: mulhdu(a, b) (multiply high double unsigned) returns | |
652 | * the high 64 bits of a * b, i.e. (a * b) >> 64, where a and b | |
653 | * are 64-bit unsigned numbers. | |
654 | */ | |
655 | unsigned long long sched_clock(void) | |
656 | { | |
96c44507 PM |
657 | if (__USE_RTC()) |
658 | return get_rtc(); | |
fc9069fe | 659 | return mulhdu(get_tb() - boot_tb, tb_to_ns_scale) << tb_to_ns_shift; |
1da177e4 LT |
660 | } |
661 | ||
4be1b297 CB |
662 | |
663 | #ifdef CONFIG_PPC_PSERIES | |
664 | ||
665 | /* | |
666 | * Running clock - attempts to give a view of time passing for a virtualised | |
667 | * kernels. | |
668 | * Uses the VTB register if available otherwise a next best guess. | |
669 | */ | |
670 | unsigned long long running_clock(void) | |
671 | { | |
672 | /* | |
673 | * Don't read the VTB as a host since KVM does not switch in host | |
674 | * timebase into the VTB when it takes a guest off the CPU, reading the | |
675 | * VTB would result in reading 'last switched out' guest VTB. | |
676 | * | |
677 | * Host kernels are often compiled with CONFIG_PPC_PSERIES checked, it | |
678 | * would be unsafe to rely only on the #ifdef above. | |
679 | */ | |
680 | if (firmware_has_feature(FW_FEATURE_LPAR) && | |
681 | cpu_has_feature(CPU_FTR_ARCH_207S)) | |
682 | return mulhdu(get_vtb() - boot_tb, tb_to_ns_scale) << tb_to_ns_shift; | |
683 | ||
684 | /* | |
685 | * This is a next best approximation without a VTB. | |
686 | * On a host which is running bare metal there should never be any stolen | |
687 | * time and on a host which doesn't do any virtualisation TB *should* equal | |
688 | * VTB so it makes no difference anyway. | |
689 | */ | |
690 | return local_clock() - cputime_to_nsecs(kcpustat_this_cpu->cpustat[CPUTIME_STEAL]); | |
691 | } | |
692 | #endif | |
693 | ||
0bb474a4 | 694 | static int __init get_freq(char *name, int cells, unsigned long *val) |
10f7e7c1 AB |
695 | { |
696 | struct device_node *cpu; | |
6f7aba7b | 697 | const __be32 *fp; |
0bb474a4 | 698 | int found = 0; |
10f7e7c1 | 699 | |
0bb474a4 | 700 | /* The cpu node should have timebase and clock frequency properties */ |
10f7e7c1 AB |
701 | cpu = of_find_node_by_type(NULL, "cpu"); |
702 | ||
d8a8188d | 703 | if (cpu) { |
e2eb6392 | 704 | fp = of_get_property(cpu, name, NULL); |
d8a8188d | 705 | if (fp) { |
0bb474a4 | 706 | found = 1; |
a4dc7ff0 | 707 | *val = of_read_ulong(fp, cells); |
10f7e7c1 | 708 | } |
0bb474a4 AB |
709 | |
710 | of_node_put(cpu); | |
10f7e7c1 | 711 | } |
0bb474a4 AB |
712 | |
713 | return found; | |
714 | } | |
715 | ||
e51df2c1 | 716 | static void start_cpu_decrementer(void) |
77c0a700 BH |
717 | { |
718 | #if defined(CONFIG_BOOKE) || defined(CONFIG_40x) | |
719 | /* Clear any pending timer interrupts */ | |
720 | mtspr(SPRN_TSR, TSR_ENW | TSR_WIS | TSR_DIS | TSR_FIS); | |
721 | ||
722 | /* Enable decrementer interrupt */ | |
723 | mtspr(SPRN_TCR, TCR_DIE); | |
724 | #endif /* defined(CONFIG_BOOKE) || defined(CONFIG_40x) */ | |
725 | } | |
726 | ||
0bb474a4 AB |
727 | void __init generic_calibrate_decr(void) |
728 | { | |
729 | ppc_tb_freq = DEFAULT_TB_FREQ; /* hardcoded default */ | |
730 | ||
731 | if (!get_freq("ibm,extended-timebase-frequency", 2, &ppc_tb_freq) && | |
732 | !get_freq("timebase-frequency", 1, &ppc_tb_freq)) { | |
733 | ||
10f7e7c1 AB |
734 | printk(KERN_ERR "WARNING: Estimating decrementer frequency " |
735 | "(not found)\n"); | |
0bb474a4 | 736 | } |
10f7e7c1 | 737 | |
0bb474a4 AB |
738 | ppc_proc_freq = DEFAULT_PROC_FREQ; /* hardcoded default */ |
739 | ||
740 | if (!get_freq("ibm,extended-clock-frequency", 2, &ppc_proc_freq) && | |
741 | !get_freq("clock-frequency", 1, &ppc_proc_freq)) { | |
742 | ||
743 | printk(KERN_ERR "WARNING: Estimating processor frequency " | |
744 | "(not found)\n"); | |
10f7e7c1 | 745 | } |
10f7e7c1 | 746 | } |
10f7e7c1 | 747 | |
aa3be5f3 | 748 | int update_persistent_clock(struct timespec now) |
f2783c15 PM |
749 | { |
750 | struct rtc_time tm; | |
751 | ||
aa3be5f3 | 752 | if (!ppc_md.set_rtc_time) |
023f333a | 753 | return -ENODEV; |
aa3be5f3 TB |
754 | |
755 | to_tm(now.tv_sec + 1 + timezone_offset, &tm); | |
756 | tm.tm_year -= 1900; | |
757 | tm.tm_mon -= 1; | |
758 | ||
759 | return ppc_md.set_rtc_time(&tm); | |
760 | } | |
761 | ||
978d7eb3 | 762 | static void __read_persistent_clock(struct timespec *ts) |
aa3be5f3 TB |
763 | { |
764 | struct rtc_time tm; | |
765 | static int first = 1; | |
766 | ||
d90246cd | 767 | ts->tv_nsec = 0; |
aa3be5f3 TB |
768 | /* XXX this is a litle fragile but will work okay in the short term */ |
769 | if (first) { | |
770 | first = 0; | |
771 | if (ppc_md.time_init) | |
772 | timezone_offset = ppc_md.time_init(); | |
773 | ||
774 | /* get_boot_time() isn't guaranteed to be safe to call late */ | |
d90246cd MS |
775 | if (ppc_md.get_boot_time) { |
776 | ts->tv_sec = ppc_md.get_boot_time() - timezone_offset; | |
777 | return; | |
778 | } | |
779 | } | |
780 | if (!ppc_md.get_rtc_time) { | |
781 | ts->tv_sec = 0; | |
782 | return; | |
aa3be5f3 | 783 | } |
f2783c15 | 784 | ppc_md.get_rtc_time(&tm); |
978d7eb3 | 785 | |
d4f587c6 MS |
786 | ts->tv_sec = mktime(tm.tm_year+1900, tm.tm_mon+1, tm.tm_mday, |
787 | tm.tm_hour, tm.tm_min, tm.tm_sec); | |
f2783c15 PM |
788 | } |
789 | ||
978d7eb3 BH |
790 | void read_persistent_clock(struct timespec *ts) |
791 | { | |
792 | __read_persistent_clock(ts); | |
793 | ||
794 | /* Sanitize it in case real time clock is set below EPOCH */ | |
795 | if (ts->tv_sec < 0) { | |
796 | ts->tv_sec = 0; | |
797 | ts->tv_nsec = 0; | |
798 | } | |
799 | ||
800 | } | |
801 | ||
4a4cfe38 | 802 | /* clocksource code */ |
8e19608e | 803 | static cycle_t rtc_read(struct clocksource *cs) |
4a4cfe38 TB |
804 | { |
805 | return (cycle_t)get_rtc(); | |
806 | } | |
807 | ||
8e19608e | 808 | static cycle_t timebase_read(struct clocksource *cs) |
4a4cfe38 TB |
809 | { |
810 | return (cycle_t)get_tb(); | |
811 | } | |
812 | ||
70639421 | 813 | void update_vsyscall_old(struct timespec *wall_time, struct timespec *wtm, |
4a0e6377 | 814 | struct clocksource *clock, u32 mult, cycle_t cycle_last) |
4a4cfe38 | 815 | { |
b0797b60 | 816 | u64 new_tb_to_xs, new_stamp_xsec; |
47916be4 | 817 | u32 frac_sec; |
4a4cfe38 TB |
818 | |
819 | if (clock != &clocksource_timebase) | |
820 | return; | |
821 | ||
822 | /* Make userspace gettimeofday spin until we're done. */ | |
823 | ++vdso_data->tb_update_count; | |
824 | smp_mb(); | |
825 | ||
11b8633a AB |
826 | /* 19342813113834067 ~= 2^(20+64) / 1e9 */ |
827 | new_tb_to_xs = (u64) mult * (19342813113834067ULL >> clock->shift); | |
06d518e3 | 828 | new_stamp_xsec = (u64) wall_time->tv_nsec * XSEC_PER_SEC; |
b0797b60 | 829 | do_div(new_stamp_xsec, 1000000000); |
06d518e3 | 830 | new_stamp_xsec += (u64) wall_time->tv_sec * XSEC_PER_SEC; |
b0797b60 | 831 | |
47916be4 TG |
832 | BUG_ON(wall_time->tv_nsec >= NSEC_PER_SEC); |
833 | /* this is tv_nsec / 1e9 as a 0.32 fraction */ | |
834 | frac_sec = ((u64) wall_time->tv_nsec * 18446744073ULL) >> 32; | |
835 | ||
b0797b60 JS |
836 | /* |
837 | * tb_update_count is used to allow the userspace gettimeofday code | |
838 | * to assure itself that it sees a consistent view of the tb_to_xs and | |
839 | * stamp_xsec variables. It reads the tb_update_count, then reads | |
840 | * tb_to_xs and stamp_xsec and then reads tb_update_count again. If | |
841 | * the two values of tb_update_count match and are even then the | |
842 | * tb_to_xs and stamp_xsec values are consistent. If not, then it | |
843 | * loops back and reads them again until this criteria is met. | |
844 | * We expect the caller to have done the first increment of | |
845 | * vdso_data->tb_update_count already. | |
846 | */ | |
4a0e6377 | 847 | vdso_data->tb_orig_stamp = cycle_last; |
b0797b60 JS |
848 | vdso_data->stamp_xsec = new_stamp_xsec; |
849 | vdso_data->tb_to_xs = new_tb_to_xs; | |
7615856e JS |
850 | vdso_data->wtom_clock_sec = wtm->tv_sec; |
851 | vdso_data->wtom_clock_nsec = wtm->tv_nsec; | |
06d518e3 | 852 | vdso_data->stamp_xtime = *wall_time; |
0e469db8 | 853 | vdso_data->stamp_sec_fraction = frac_sec; |
b0797b60 JS |
854 | smp_wmb(); |
855 | ++(vdso_data->tb_update_count); | |
4a4cfe38 TB |
856 | } |
857 | ||
858 | void update_vsyscall_tz(void) | |
859 | { | |
4a4cfe38 TB |
860 | vdso_data->tz_minuteswest = sys_tz.tz_minuteswest; |
861 | vdso_data->tz_dsttime = sys_tz.tz_dsttime; | |
4a4cfe38 TB |
862 | } |
863 | ||
1c21a293 | 864 | static void __init clocksource_init(void) |
4a4cfe38 TB |
865 | { |
866 | struct clocksource *clock; | |
867 | ||
868 | if (__USE_RTC()) | |
869 | clock = &clocksource_rtc; | |
870 | else | |
871 | clock = &clocksource_timebase; | |
872 | ||
11b8633a | 873 | if (clocksource_register_hz(clock, tb_ticks_per_sec)) { |
4a4cfe38 TB |
874 | printk(KERN_ERR "clocksource: %s is already registered\n", |
875 | clock->name); | |
876 | return; | |
877 | } | |
878 | ||
879 | printk(KERN_INFO "clocksource: %s mult[%x] shift[%d] registered\n", | |
880 | clock->name, clock->mult, clock->shift); | |
881 | } | |
882 | ||
d831d0b8 TB |
883 | static int decrementer_set_next_event(unsigned long evt, |
884 | struct clock_event_device *dev) | |
885 | { | |
69111bac | 886 | __this_cpu_write(decrementers_next_tb, get_tb_or_rtc() + evt); |
d831d0b8 | 887 | set_dec(evt); |
0215f7d8 BH |
888 | |
889 | /* We may have raced with new irq work */ | |
890 | if (test_irq_work_pending()) | |
891 | set_dec(1); | |
892 | ||
d831d0b8 TB |
893 | return 0; |
894 | } | |
895 | ||
37a13e78 | 896 | static int decrementer_shutdown(struct clock_event_device *dev) |
d831d0b8 | 897 | { |
79901024 | 898 | decrementer_set_next_event(decrementer_max, dev); |
37a13e78 | 899 | return 0; |
d831d0b8 TB |
900 | } |
901 | ||
1b67bee1 SB |
902 | /* Interrupt handler for the timer broadcast IPI */ |
903 | void tick_broadcast_ipi_handler(void) | |
904 | { | |
69111bac | 905 | u64 *next_tb = this_cpu_ptr(&decrementers_next_tb); |
1b783955 PM |
906 | |
907 | *next_tb = get_tb_or_rtc(); | |
908 | __timer_interrupt(); | |
1b67bee1 SB |
909 | } |
910 | ||
d831d0b8 TB |
911 | static void register_decrementer_clockevent(int cpu) |
912 | { | |
7df10275 | 913 | struct clock_event_device *dec = &per_cpu(decrementers, cpu); |
d831d0b8 TB |
914 | |
915 | *dec = decrementer_clockevent; | |
320ab2b0 | 916 | dec->cpumask = cpumask_of(cpu); |
d831d0b8 | 917 | |
b919ee82 AB |
918 | printk_once(KERN_DEBUG "clockevent: %s mult[%x] shift[%d] cpu[%d]\n", |
919 | dec->name, dec->mult, dec->shift, cpu); | |
d831d0b8 TB |
920 | |
921 | clockevents_register_device(dec); | |
922 | } | |
923 | ||
79901024 OH |
924 | static void enable_large_decrementer(void) |
925 | { | |
926 | if (!cpu_has_feature(CPU_FTR_ARCH_300)) | |
927 | return; | |
928 | ||
929 | if (decrementer_max <= DECREMENTER_DEFAULT_MAX) | |
930 | return; | |
931 | ||
932 | /* | |
933 | * If we're running as the hypervisor we need to enable the LD manually | |
934 | * otherwise firmware should have done it for us. | |
935 | */ | |
936 | if (cpu_has_feature(CPU_FTR_HVMODE)) | |
937 | mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) | LPCR_LD); | |
938 | } | |
939 | ||
940 | static void __init set_decrementer_max(void) | |
941 | { | |
942 | struct device_node *cpu; | |
943 | u32 bits = 32; | |
944 | ||
945 | /* Prior to ISAv3 the decrementer is always 32 bit */ | |
946 | if (!cpu_has_feature(CPU_FTR_ARCH_300)) | |
947 | return; | |
948 | ||
949 | cpu = of_find_node_by_type(NULL, "cpu"); | |
950 | ||
951 | if (of_property_read_u32(cpu, "ibm,dec-bits", &bits) == 0) { | |
952 | if (bits > 64 || bits < 32) { | |
953 | pr_warn("time_init: firmware supplied invalid ibm,dec-bits"); | |
954 | bits = 32; | |
955 | } | |
956 | ||
957 | /* calculate the signed maximum given this many bits */ | |
958 | decrementer_max = (1ul << (bits - 1)) - 1; | |
959 | } | |
960 | ||
961 | of_node_put(cpu); | |
962 | ||
963 | pr_info("time_init: %u bit decrementer (max: %llx)\n", | |
964 | bits, decrementer_max); | |
965 | } | |
966 | ||
c481887f | 967 | static void __init init_decrementer_clockevent(void) |
d831d0b8 TB |
968 | { |
969 | int cpu = smp_processor_id(); | |
970 | ||
d8afc6fd AB |
971 | clockevents_calc_mult_shift(&decrementer_clockevent, ppc_tb_freq, 4); |
972 | ||
d831d0b8 | 973 | decrementer_clockevent.max_delta_ns = |
79901024 | 974 | clockevent_delta2ns(decrementer_max, &decrementer_clockevent); |
43875cc0 PM |
975 | decrementer_clockevent.min_delta_ns = |
976 | clockevent_delta2ns(2, &decrementer_clockevent); | |
d831d0b8 TB |
977 | |
978 | register_decrementer_clockevent(cpu); | |
979 | } | |
980 | ||
981 | void secondary_cpu_time_init(void) | |
982 | { | |
79901024 OH |
983 | /* Enable and test the large decrementer for this cpu */ |
984 | enable_large_decrementer(); | |
985 | ||
77c0a700 BH |
986 | /* Start the decrementer on CPUs that have manual control |
987 | * such as BookE | |
988 | */ | |
989 | start_cpu_decrementer(); | |
990 | ||
d831d0b8 TB |
991 | /* FIME: Should make unrelatred change to move snapshot_timebase |
992 | * call here ! */ | |
993 | register_decrementer_clockevent(smp_processor_id()); | |
994 | } | |
995 | ||
f2783c15 | 996 | /* This function is only called on the boot processor */ |
1da177e4 LT |
997 | void __init time_init(void) |
998 | { | |
1da177e4 | 999 | struct div_result res; |
d75d68cf | 1000 | u64 scale; |
f2783c15 PM |
1001 | unsigned shift; |
1002 | ||
96c44507 PM |
1003 | if (__USE_RTC()) { |
1004 | /* 601 processor: dec counts down by 128 every 128ns */ | |
1005 | ppc_tb_freq = 1000000000; | |
96c44507 PM |
1006 | } else { |
1007 | /* Normal PowerPC with timebase register */ | |
1008 | ppc_md.calibrate_decr(); | |
224ad80a | 1009 | printk(KERN_DEBUG "time_init: decrementer frequency = %lu.%.6lu MHz\n", |
96c44507 | 1010 | ppc_tb_freq / 1000000, ppc_tb_freq % 1000000); |
224ad80a | 1011 | printk(KERN_DEBUG "time_init: processor frequency = %lu.%.6lu MHz\n", |
96c44507 | 1012 | ppc_proc_freq / 1000000, ppc_proc_freq % 1000000); |
96c44507 | 1013 | } |
374e99d4 PM |
1014 | |
1015 | tb_ticks_per_jiffy = ppc_tb_freq / HZ; | |
092b8f34 | 1016 | tb_ticks_per_sec = ppc_tb_freq; |
374e99d4 | 1017 | tb_ticks_per_usec = ppc_tb_freq / 1000000; |
c6622f63 | 1018 | calc_cputime_factors(); |
a42548a1 | 1019 | setup_cputime_one_jiffy(); |
092b8f34 | 1020 | |
1da177e4 LT |
1021 | /* |
1022 | * Compute scale factor for sched_clock. | |
1023 | * The calibrate_decr() function has set tb_ticks_per_sec, | |
1024 | * which is the timebase frequency. | |
1025 | * We compute 1e9 * 2^64 / tb_ticks_per_sec and interpret | |
1026 | * the 128-bit result as a 64.64 fixed-point number. | |
1027 | * We then shift that number right until it is less than 1.0, | |
1028 | * giving us the scale factor and shift count to use in | |
1029 | * sched_clock(). | |
1030 | */ | |
1031 | div128_by_32(1000000000, 0, tb_ticks_per_sec, &res); | |
1032 | scale = res.result_low; | |
1033 | for (shift = 0; res.result_high != 0; ++shift) { | |
1034 | scale = (scale >> 1) | (res.result_high << 63); | |
1035 | res.result_high >>= 1; | |
1036 | } | |
1037 | tb_to_ns_scale = scale; | |
1038 | tb_to_ns_shift = shift; | |
fc9069fe | 1039 | /* Save the current timebase to pretty up CONFIG_PRINTK_TIME */ |
c27da339 | 1040 | boot_tb = get_tb_or_rtc(); |
1da177e4 | 1041 | |
092b8f34 | 1042 | /* If platform provided a timezone (pmac), we correct the time */ |
621692cb | 1043 | if (timezone_offset) { |
092b8f34 PM |
1044 | sys_tz.tz_minuteswest = -timezone_offset / 60; |
1045 | sys_tz.tz_dsttime = 0; | |
621692cb | 1046 | } |
092b8f34 | 1047 | |
a7f290da BH |
1048 | vdso_data->tb_update_count = 0; |
1049 | vdso_data->tb_ticks_per_sec = tb_ticks_per_sec; | |
1da177e4 | 1050 | |
79901024 OH |
1051 | /* initialise and enable the large decrementer (if we have one) */ |
1052 | set_decrementer_max(); | |
1053 | enable_large_decrementer(); | |
1054 | ||
77c0a700 BH |
1055 | /* Start the decrementer on CPUs that have manual control |
1056 | * such as BookE | |
1057 | */ | |
1058 | start_cpu_decrementer(); | |
1059 | ||
f5339277 SR |
1060 | /* Register the clocksource */ |
1061 | clocksource_init(); | |
4a4cfe38 | 1062 | |
d831d0b8 | 1063 | init_decrementer_clockevent(); |
0d948730 | 1064 | tick_setup_hrtimer_broadcast(); |
f0d37300 KH |
1065 | |
1066 | #ifdef CONFIG_COMMON_CLK | |
1067 | of_clk_init(NULL); | |
1068 | #endif | |
1da177e4 LT |
1069 | } |
1070 | ||
1da177e4 | 1071 | |
1da177e4 LT |
1072 | #define FEBRUARY 2 |
1073 | #define STARTOFTIME 1970 | |
1074 | #define SECDAY 86400L | |
1075 | #define SECYR (SECDAY * 365) | |
f2783c15 PM |
1076 | #define leapyear(year) ((year) % 4 == 0 && \ |
1077 | ((year) % 100 != 0 || (year) % 400 == 0)) | |
1da177e4 LT |
1078 | #define days_in_year(a) (leapyear(a) ? 366 : 365) |
1079 | #define days_in_month(a) (month_days[(a) - 1]) | |
1080 | ||
1081 | static int month_days[12] = { | |
1082 | 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 | |
1083 | }; | |
1084 | ||
1da177e4 LT |
1085 | void to_tm(int tim, struct rtc_time * tm) |
1086 | { | |
1087 | register int i; | |
1088 | register long hms, day; | |
1089 | ||
1090 | day = tim / SECDAY; | |
1091 | hms = tim % SECDAY; | |
1092 | ||
1093 | /* Hours, minutes, seconds are easy */ | |
1094 | tm->tm_hour = hms / 3600; | |
1095 | tm->tm_min = (hms % 3600) / 60; | |
1096 | tm->tm_sec = (hms % 3600) % 60; | |
1097 | ||
1098 | /* Number of years in days */ | |
1099 | for (i = STARTOFTIME; day >= days_in_year(i); i++) | |
1100 | day -= days_in_year(i); | |
1101 | tm->tm_year = i; | |
1102 | ||
1103 | /* Number of months in days left */ | |
1104 | if (leapyear(tm->tm_year)) | |
1105 | days_in_month(FEBRUARY) = 29; | |
1106 | for (i = 1; day >= days_in_month(i); i++) | |
1107 | day -= days_in_month(i); | |
1108 | days_in_month(FEBRUARY) = 28; | |
1109 | tm->tm_mon = i; | |
1110 | ||
1111 | /* Days are what is left over (+1) from all that. */ | |
1112 | tm->tm_mday = day + 1; | |
1113 | ||
1114 | /* | |
00b912b0 | 1115 | * No-one uses the day of the week. |
1da177e4 | 1116 | */ |
00b912b0 | 1117 | tm->tm_wday = -1; |
1da177e4 | 1118 | } |
e1802b06 | 1119 | EXPORT_SYMBOL(to_tm); |
1da177e4 | 1120 | |
1da177e4 LT |
1121 | /* |
1122 | * Divide a 128-bit dividend by a 32-bit divisor, leaving a 128 bit | |
1123 | * result. | |
1124 | */ | |
f2783c15 PM |
1125 | void div128_by_32(u64 dividend_high, u64 dividend_low, |
1126 | unsigned divisor, struct div_result *dr) | |
1da177e4 | 1127 | { |
f2783c15 PM |
1128 | unsigned long a, b, c, d; |
1129 | unsigned long w, x, y, z; | |
1130 | u64 ra, rb, rc; | |
1da177e4 LT |
1131 | |
1132 | a = dividend_high >> 32; | |
1133 | b = dividend_high & 0xffffffff; | |
1134 | c = dividend_low >> 32; | |
1135 | d = dividend_low & 0xffffffff; | |
1136 | ||
f2783c15 PM |
1137 | w = a / divisor; |
1138 | ra = ((u64)(a - (w * divisor)) << 32) + b; | |
1139 | ||
f2783c15 PM |
1140 | rb = ((u64) do_div(ra, divisor) << 32) + c; |
1141 | x = ra; | |
1da177e4 | 1142 | |
f2783c15 PM |
1143 | rc = ((u64) do_div(rb, divisor) << 32) + d; |
1144 | y = rb; | |
1145 | ||
1146 | do_div(rc, divisor); | |
1147 | z = rc; | |
1da177e4 | 1148 | |
f2783c15 PM |
1149 | dr->result_high = ((u64)w << 32) + x; |
1150 | dr->result_low = ((u64)y << 32) + z; | |
1da177e4 LT |
1151 | |
1152 | } | |
bcd68a70 | 1153 | |
177996e6 BH |
1154 | /* We don't need to calibrate delay, we use the CPU timebase for that */ |
1155 | void calibrate_delay(void) | |
1156 | { | |
1157 | /* Some generic code (such as spinlock debug) use loops_per_jiffy | |
1158 | * as the number of __delay(1) in a jiffy, so make it so | |
1159 | */ | |
1160 | loops_per_jiffy = tb_ticks_per_jiffy; | |
1161 | } | |
1162 | ||
169047f4 AB |
1163 | #if IS_ENABLED(CONFIG_RTC_DRV_GENERIC) |
1164 | static int rtc_generic_get_time(struct device *dev, struct rtc_time *tm) | |
1165 | { | |
1166 | ppc_md.get_rtc_time(tm); | |
1167 | return rtc_valid_tm(tm); | |
1168 | } | |
1169 | ||
1170 | static int rtc_generic_set_time(struct device *dev, struct rtc_time *tm) | |
1171 | { | |
1172 | if (!ppc_md.set_rtc_time) | |
1173 | return -EOPNOTSUPP; | |
1174 | ||
1175 | if (ppc_md.set_rtc_time(tm) < 0) | |
1176 | return -EOPNOTSUPP; | |
1177 | ||
1178 | return 0; | |
1179 | } | |
1180 | ||
1181 | static const struct rtc_class_ops rtc_generic_ops = { | |
1182 | .read_time = rtc_generic_get_time, | |
1183 | .set_time = rtc_generic_set_time, | |
1184 | }; | |
1185 | ||
bcd68a70 GU |
1186 | static int __init rtc_init(void) |
1187 | { | |
1188 | struct platform_device *pdev; | |
1189 | ||
1190 | if (!ppc_md.get_rtc_time) | |
1191 | return -ENODEV; | |
1192 | ||
169047f4 AB |
1193 | pdev = platform_device_register_data(NULL, "rtc-generic", -1, |
1194 | &rtc_generic_ops, | |
1195 | sizeof(rtc_generic_ops)); | |
bcd68a70 | 1196 | |
8c6ffba0 | 1197 | return PTR_ERR_OR_ZERO(pdev); |
bcd68a70 GU |
1198 | } |
1199 | ||
8f6b9512 | 1200 | device_initcall(rtc_init); |
169047f4 | 1201 | #endif |