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12#include <linux/cpu.h>
13#include <linux/init.h>
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/profile.h>
17#include <linux/sched.h>
18#include <linux/time.h>
19#include <linux/interrupt.h>
20#include <linux/efi.h>
21#include <linux/timex.h>
22#include <linux/clocksource.h>
23#include <linux/platform_device.h>
24
25#include <asm/machvec.h>
26#include <asm/delay.h>
27#include <asm/hw_irq.h>
28#include <asm/paravirt.h>
29#include <asm/ptrace.h>
30#include <asm/sal.h>
31#include <asm/sections.h>
32#include <asm/system.h>
33
34#include "fsyscall_gtod_data.h"
35
36static cycle_t itc_get_cycles(struct clocksource *cs);
37
38struct fsyscall_gtod_data_t fsyscall_gtod_data = {
39 .lock = SEQLOCK_UNLOCKED,
40};
41
42struct itc_jitter_data_t itc_jitter_data;
43
44volatile int time_keeper_id = 0;
45
46#ifdef CONFIG_IA64_DEBUG_IRQ
47
48unsigned long last_cli_ip;
49EXPORT_SYMBOL(last_cli_ip);
50
51#endif
52
53#ifdef CONFIG_PARAVIRT
54
55
56unsigned long long sched_clock(void)
57{
58 return paravirt_sched_clock();
59}
60#endif
61
62#ifdef CONFIG_PARAVIRT
63static void
64paravirt_clocksource_resume(void)
65{
66 if (pv_time_ops.clocksource_resume)
67 pv_time_ops.clocksource_resume();
68}
69#endif
70
71static struct clocksource clocksource_itc = {
72 .name = "itc",
73 .rating = 350,
74 .read = itc_get_cycles,
75 .mask = CLOCKSOURCE_MASK(64),
76 .mult = 0,
77 .shift = 16,
78 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
79#ifdef CONFIG_PARAVIRT
80 .resume = paravirt_clocksource_resume,
81#endif
82};
83static struct clocksource *itc_clocksource;
84
85#ifdef CONFIG_VIRT_CPU_ACCOUNTING
86
87#include <linux/kernel_stat.h>
88
89extern cputime_t cycle_to_cputime(u64 cyc);
90
91
92
93
94
95
96void ia64_account_on_switch(struct task_struct *prev, struct task_struct *next)
97{
98 struct thread_info *pi = task_thread_info(prev);
99 struct thread_info *ni = task_thread_info(next);
100 cputime_t delta_stime, delta_utime;
101 __u64 now;
102
103 now = ia64_get_itc();
104
105 delta_stime = cycle_to_cputime(pi->ac_stime + (now - pi->ac_stamp));
106 if (idle_task(smp_processor_id()) != prev)
107 account_system_time(prev, 0, delta_stime, delta_stime);
108 else
109 account_idle_time(delta_stime);
110
111 if (pi->ac_utime) {
112 delta_utime = cycle_to_cputime(pi->ac_utime);
113 account_user_time(prev, delta_utime, delta_utime);
114 }
115
116 pi->ac_stamp = ni->ac_stamp = now;
117 ni->ac_stime = ni->ac_utime = 0;
118}
119
120
121
122
123
124void account_system_vtime(struct task_struct *tsk)
125{
126 struct thread_info *ti = task_thread_info(tsk);
127 unsigned long flags;
128 cputime_t delta_stime;
129 __u64 now;
130
131 local_irq_save(flags);
132
133 now = ia64_get_itc();
134
135 delta_stime = cycle_to_cputime(ti->ac_stime + (now - ti->ac_stamp));
136 if (irq_count() || idle_task(smp_processor_id()) != tsk)
137 account_system_time(tsk, 0, delta_stime, delta_stime);
138 else
139 account_idle_time(delta_stime);
140 ti->ac_stime = 0;
141
142 ti->ac_stamp = now;
143
144 local_irq_restore(flags);
145}
146EXPORT_SYMBOL_GPL(account_system_vtime);
147
148
149
150
151
152void account_process_tick(struct task_struct *p, int user_tick)
153{
154 struct thread_info *ti = task_thread_info(p);
155 cputime_t delta_utime;
156
157 if (ti->ac_utime) {
158 delta_utime = cycle_to_cputime(ti->ac_utime);
159 account_user_time(p, delta_utime, delta_utime);
160 ti->ac_utime = 0;
161 }
162}
163
164#endif
165
166static irqreturn_t
167timer_interrupt (int irq, void *dev_id)
168{
169 unsigned long new_itm;
170
171 if (unlikely(cpu_is_offline(smp_processor_id()))) {
172 return IRQ_HANDLED;
173 }
174
175 platform_timer_interrupt(irq, dev_id);
176
177 new_itm = local_cpu_data->itm_next;
178
179 if (!time_after(ia64_get_itc(), new_itm))
180 printk(KERN_ERR "Oops: timer tick before it's due (itc=%lx,itm=%lx)\n",
181 ia64_get_itc(), new_itm);
182
183 profile_tick(CPU_PROFILING);
184
185 if (paravirt_do_steal_accounting(&new_itm))
186 goto skip_process_time_accounting;
187
188 while (1) {
189 update_process_times(user_mode(get_irq_regs()));
190
191 new_itm += local_cpu_data->itm_delta;
192
193 if (smp_processor_id() == time_keeper_id) {
194
195
196
197
198
199
200 write_seqlock(&xtime_lock);
201 do_timer(1);
202 local_cpu_data->itm_next = new_itm;
203 write_sequnlock(&xtime_lock);
204 } else
205 local_cpu_data->itm_next = new_itm;
206
207 if (time_after(new_itm, ia64_get_itc()))
208 break;
209
210
211
212
213 local_irq_enable();
214 local_irq_disable();
215 }
216
217skip_process_time_accounting:
218
219 do {
220
221
222
223
224
225
226
227
228
229 while (!time_after(new_itm, ia64_get_itc() + local_cpu_data->itm_delta/2))
230 new_itm += local_cpu_data->itm_delta;
231 ia64_set_itm(new_itm);
232
233 } while (time_after_eq(ia64_get_itc(), new_itm));
234 return IRQ_HANDLED;
235}
236
237
238
239
240void
241ia64_cpu_local_tick (void)
242{
243 int cpu = smp_processor_id();
244 unsigned long shift = 0, delta;
245
246
247 ia64_set_itv(IA64_TIMER_VECTOR);
248
249 delta = local_cpu_data->itm_delta;
250
251
252
253
254 if (cpu) {
255 unsigned long hi = 1UL << ia64_fls(cpu);
256 shift = (2*(cpu - hi) + 1) * delta/hi/2;
257 }
258 local_cpu_data->itm_next = ia64_get_itc() + delta + shift;
259 ia64_set_itm(local_cpu_data->itm_next);
260}
261
262static int nojitter;
263
264static int __init nojitter_setup(char *str)
265{
266 nojitter = 1;
267 printk("Jitter checking for ITC timers disabled\n");
268 return 1;
269}
270
271__setup("nojitter", nojitter_setup);
272
273
274void __devinit
275ia64_init_itm (void)
276{
277 unsigned long platform_base_freq, itc_freq;
278 struct pal_freq_ratio itc_ratio, proc_ratio;
279 long status, platform_base_drift, itc_drift;
280
281
282
283
284
285
286 status = ia64_sal_freq_base(SAL_FREQ_BASE_PLATFORM,
287 &platform_base_freq, &platform_base_drift);
288 if (status != 0) {
289 printk(KERN_ERR "SAL_FREQ_BASE_PLATFORM failed: %s\n", ia64_sal_strerror(status));
290 } else {
291 status = ia64_pal_freq_ratios(&proc_ratio, NULL, &itc_ratio);
292 if (status != 0)
293 printk(KERN_ERR "PAL_FREQ_RATIOS failed with status=%ld\n", status);
294 }
295 if (status != 0) {
296
297 printk(KERN_ERR
298 "SAL/PAL failed to obtain frequency info---inventing reasonable values\n");
299 platform_base_freq = 100000000;
300 platform_base_drift = -1;
301 itc_ratio.num = 3;
302 itc_ratio.den = 1;
303 }
304 if (platform_base_freq < 40000000) {
305 printk(KERN_ERR "Platform base frequency %lu bogus---resetting to 75MHz!\n",
306 platform_base_freq);
307 platform_base_freq = 75000000;
308 platform_base_drift = -1;
309 }
310 if (!proc_ratio.den)
311 proc_ratio.den = 1;
312 if (!itc_ratio.den)
313 itc_ratio.den = 1;
314
315 itc_freq = (platform_base_freq*itc_ratio.num)/itc_ratio.den;
316
317 local_cpu_data->itm_delta = (itc_freq + HZ/2) / HZ;
318 printk(KERN_DEBUG "CPU %d: base freq=%lu.%03luMHz, ITC ratio=%u/%u, "
319 "ITC freq=%lu.%03luMHz", smp_processor_id(),
320 platform_base_freq / 1000000, (platform_base_freq / 1000) % 1000,
321 itc_ratio.num, itc_ratio.den, itc_freq / 1000000, (itc_freq / 1000) % 1000);
322
323 if (platform_base_drift != -1) {
324 itc_drift = platform_base_drift*itc_ratio.num/itc_ratio.den;
325 printk("+/-%ldppm\n", itc_drift);
326 } else {
327 itc_drift = -1;
328 printk("\n");
329 }
330
331 local_cpu_data->proc_freq = (platform_base_freq*proc_ratio.num)/proc_ratio.den;
332 local_cpu_data->itc_freq = itc_freq;
333 local_cpu_data->cyc_per_usec = (itc_freq + USEC_PER_SEC/2) / USEC_PER_SEC;
334 local_cpu_data->nsec_per_cyc = ((NSEC_PER_SEC<<IA64_NSEC_PER_CYC_SHIFT)
335 + itc_freq/2)/itc_freq;
336
337 if (!(sal_platform_features & IA64_SAL_PLATFORM_FEATURE_ITC_DRIFT)) {
338#ifdef CONFIG_SMP
339
340
341
342
343
344
345
346
347
348
349 if (!nojitter)
350 itc_jitter_data.itc_jitter = 1;
351#endif
352 } else
353
354
355
356
357
358
359
360
361
362
363
364
365
366 clocksource_itc.rating = 50;
367
368 paravirt_init_missing_ticks_accounting(smp_processor_id());
369
370
371 touch_softlockup_watchdog();
372
373
374 ia64_cpu_local_tick();
375
376 if (!itc_clocksource) {
377
378 clocksource_itc.mult =
379 clocksource_hz2mult(local_cpu_data->itc_freq,
380 clocksource_itc.shift);
381 clocksource_register(&clocksource_itc);
382 itc_clocksource = &clocksource_itc;
383 }
384}
385
386static cycle_t itc_get_cycles(struct clocksource *cs)
387{
388 unsigned long lcycle, now, ret;
389
390 if (!itc_jitter_data.itc_jitter)
391 return get_cycles();
392
393 lcycle = itc_jitter_data.itc_lastcycle;
394 now = get_cycles();
395 if (lcycle && time_after(lcycle, now))
396 return lcycle;
397
398
399
400
401
402
403
404 ret = cmpxchg(&itc_jitter_data.itc_lastcycle, lcycle, now);
405 if (unlikely(ret != lcycle))
406 return ret;
407
408 return now;
409}
410
411
412static struct irqaction timer_irqaction = {
413 .handler = timer_interrupt,
414 .flags = IRQF_DISABLED | IRQF_IRQPOLL,
415 .name = "timer"
416};
417
418static struct platform_device rtc_efi_dev = {
419 .name = "rtc-efi",
420 .id = -1,
421};
422
423static int __init rtc_init(void)
424{
425 if (platform_device_register(&rtc_efi_dev) < 0)
426 printk(KERN_ERR "unable to register rtc device...\n");
427
428
429 return 0;
430}
431module_init(rtc_init);
432
433void __init
434time_init (void)
435{
436 register_percpu_irq(IA64_TIMER_VECTOR, &timer_irqaction);
437 efi_gettimeofday(&xtime);
438 ia64_init_itm();
439
440
441
442
443
444 set_normalized_timespec(&wall_to_monotonic, -xtime.tv_sec, -xtime.tv_nsec);
445}
446
447
448
449
450
451
452static void
453ia64_itc_udelay (unsigned long usecs)
454{
455 unsigned long start = ia64_get_itc();
456 unsigned long end = start + usecs*local_cpu_data->cyc_per_usec;
457
458 while (time_before(ia64_get_itc(), end))
459 cpu_relax();
460}
461
462void (*ia64_udelay)(unsigned long usecs) = &ia64_itc_udelay;
463
464void
465udelay (unsigned long usecs)
466{
467 (*ia64_udelay)(usecs);
468}
469EXPORT_SYMBOL(udelay);
470
471
472void update_vsyscall_tz(void)
473{
474}
475
476void update_vsyscall(struct timespec *wall, struct clocksource *c)
477{
478 unsigned long flags;
479
480 write_seqlock_irqsave(&fsyscall_gtod_data.lock, flags);
481
482
483 fsyscall_gtod_data.clk_mask = c->mask;
484 fsyscall_gtod_data.clk_mult = c->mult;
485 fsyscall_gtod_data.clk_shift = c->shift;
486 fsyscall_gtod_data.clk_fsys_mmio = c->fsys_mmio;
487 fsyscall_gtod_data.clk_cycle_last = c->cycle_last;
488
489
490 fsyscall_gtod_data.wall_time.tv_sec = wall->tv_sec;
491 fsyscall_gtod_data.wall_time.tv_nsec = wall->tv_nsec;
492 fsyscall_gtod_data.monotonic_time.tv_sec = wall_to_monotonic.tv_sec
493 + wall->tv_sec;
494 fsyscall_gtod_data.monotonic_time.tv_nsec = wall_to_monotonic.tv_nsec
495 + wall->tv_nsec;
496
497
498 while (fsyscall_gtod_data.monotonic_time.tv_nsec >= NSEC_PER_SEC) {
499 fsyscall_gtod_data.monotonic_time.tv_nsec -= NSEC_PER_SEC;
500 fsyscall_gtod_data.monotonic_time.tv_sec++;
501 }
502
503 write_sequnlock_irqrestore(&fsyscall_gtod_data.lock, flags);
504}
505
506