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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
33#include "fsyscall_gtod_data.h"
34
35static cycle_t itc_get_cycles(struct clocksource *cs);
36
37struct fsyscall_gtod_data_t fsyscall_gtod_data;
38
39struct itc_jitter_data_t itc_jitter_data;
40
41volatile int time_keeper_id = 0;
42
43#ifdef CONFIG_IA64_DEBUG_IRQ
44
45unsigned long last_cli_ip;
46EXPORT_SYMBOL(last_cli_ip);
47
48#endif
49
50#ifdef CONFIG_PARAVIRT
51
52
53unsigned long long sched_clock(void)
54{
55 return paravirt_sched_clock();
56}
57#endif
58
59#ifdef CONFIG_PARAVIRT
60static void
61paravirt_clocksource_resume(struct clocksource *cs)
62{
63 if (pv_time_ops.clocksource_resume)
64 pv_time_ops.clocksource_resume();
65}
66#endif
67
68static struct clocksource clocksource_itc = {
69 .name = "itc",
70 .rating = 350,
71 .read = itc_get_cycles,
72 .mask = CLOCKSOURCE_MASK(64),
73 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
74#ifdef CONFIG_PARAVIRT
75 .resume = paravirt_clocksource_resume,
76#endif
77};
78static struct clocksource *itc_clocksource;
79
80#ifdef CONFIG_VIRT_CPU_ACCOUNTING
81
82#include <linux/kernel_stat.h>
83
84extern cputime_t cycle_to_cputime(u64 cyc);
85
86
87
88
89
90
91void ia64_account_on_switch(struct task_struct *prev, struct task_struct *next)
92{
93 struct thread_info *pi = task_thread_info(prev);
94 struct thread_info *ni = task_thread_info(next);
95 cputime_t delta_stime, delta_utime;
96 __u64 now;
97
98 now = ia64_get_itc();
99
100 delta_stime = cycle_to_cputime(pi->ac_stime + (now - pi->ac_stamp));
101 if (idle_task(smp_processor_id()) != prev)
102 account_system_time(prev, 0, delta_stime, delta_stime);
103 else
104 account_idle_time(delta_stime);
105
106 if (pi->ac_utime) {
107 delta_utime = cycle_to_cputime(pi->ac_utime);
108 account_user_time(prev, delta_utime, delta_utime);
109 }
110
111 pi->ac_stamp = ni->ac_stamp = now;
112 ni->ac_stime = ni->ac_utime = 0;
113}
114
115
116
117
118
119void account_system_vtime(struct task_struct *tsk)
120{
121 struct thread_info *ti = task_thread_info(tsk);
122 unsigned long flags;
123 cputime_t delta_stime;
124 __u64 now;
125
126 local_irq_save(flags);
127
128 now = ia64_get_itc();
129
130 delta_stime = cycle_to_cputime(ti->ac_stime + (now - ti->ac_stamp));
131 if (irq_count() || idle_task(smp_processor_id()) != tsk)
132 account_system_time(tsk, 0, delta_stime, delta_stime);
133 else
134 account_idle_time(delta_stime);
135 ti->ac_stime = 0;
136
137 ti->ac_stamp = now;
138
139 local_irq_restore(flags);
140}
141EXPORT_SYMBOL_GPL(account_system_vtime);
142
143
144
145
146
147void account_process_tick(struct task_struct *p, int user_tick)
148{
149 struct thread_info *ti = task_thread_info(p);
150 cputime_t delta_utime;
151
152 if (ti->ac_utime) {
153 delta_utime = cycle_to_cputime(ti->ac_utime);
154 account_user_time(p, delta_utime, delta_utime);
155 ti->ac_utime = 0;
156 }
157}
158
159#endif
160
161static irqreturn_t
162timer_interrupt (int irq, void *dev_id)
163{
164 unsigned long new_itm;
165
166 if (cpu_is_offline(smp_processor_id())) {
167 return IRQ_HANDLED;
168 }
169
170 platform_timer_interrupt(irq, dev_id);
171
172 new_itm = local_cpu_data->itm_next;
173
174 if (!time_after(ia64_get_itc(), new_itm))
175 printk(KERN_ERR "Oops: timer tick before it's due (itc=%lx,itm=%lx)\n",
176 ia64_get_itc(), new_itm);
177
178 profile_tick(CPU_PROFILING);
179
180 if (paravirt_do_steal_accounting(&new_itm))
181 goto skip_process_time_accounting;
182
183 while (1) {
184 update_process_times(user_mode(get_irq_regs()));
185
186 new_itm += local_cpu_data->itm_delta;
187
188 if (smp_processor_id() == time_keeper_id)
189 xtime_update(1);
190
191 local_cpu_data->itm_next = new_itm;
192
193 if (time_after(new_itm, ia64_get_itc()))
194 break;
195
196
197
198
199 local_irq_enable();
200 local_irq_disable();
201 }
202
203skip_process_time_accounting:
204
205 do {
206
207
208
209
210
211
212
213
214
215 while (!time_after(new_itm, ia64_get_itc() + local_cpu_data->itm_delta/2))
216 new_itm += local_cpu_data->itm_delta;
217 ia64_set_itm(new_itm);
218
219 } while (time_after_eq(ia64_get_itc(), new_itm));
220 return IRQ_HANDLED;
221}
222
223
224
225
226void
227ia64_cpu_local_tick (void)
228{
229 int cpu = smp_processor_id();
230 unsigned long shift = 0, delta;
231
232
233 ia64_set_itv(IA64_TIMER_VECTOR);
234
235 delta = local_cpu_data->itm_delta;
236
237
238
239
240 if (cpu) {
241 unsigned long hi = 1UL << ia64_fls(cpu);
242 shift = (2*(cpu - hi) + 1) * delta/hi/2;
243 }
244 local_cpu_data->itm_next = ia64_get_itc() + delta + shift;
245 ia64_set_itm(local_cpu_data->itm_next);
246}
247
248static int nojitter;
249
250static int __init nojitter_setup(char *str)
251{
252 nojitter = 1;
253 printk("Jitter checking for ITC timers disabled\n");
254 return 1;
255}
256
257__setup("nojitter", nojitter_setup);
258
259
260void __devinit
261ia64_init_itm (void)
262{
263 unsigned long platform_base_freq, itc_freq;
264 struct pal_freq_ratio itc_ratio, proc_ratio;
265 long status, platform_base_drift, itc_drift;
266
267
268
269
270
271
272 status = ia64_sal_freq_base(SAL_FREQ_BASE_PLATFORM,
273 &platform_base_freq, &platform_base_drift);
274 if (status != 0) {
275 printk(KERN_ERR "SAL_FREQ_BASE_PLATFORM failed: %s\n", ia64_sal_strerror(status));
276 } else {
277 status = ia64_pal_freq_ratios(&proc_ratio, NULL, &itc_ratio);
278 if (status != 0)
279 printk(KERN_ERR "PAL_FREQ_RATIOS failed with status=%ld\n", status);
280 }
281 if (status != 0) {
282
283 printk(KERN_ERR
284 "SAL/PAL failed to obtain frequency info---inventing reasonable values\n");
285 platform_base_freq = 100000000;
286 platform_base_drift = -1;
287 itc_ratio.num = 3;
288 itc_ratio.den = 1;
289 }
290 if (platform_base_freq < 40000000) {
291 printk(KERN_ERR "Platform base frequency %lu bogus---resetting to 75MHz!\n",
292 platform_base_freq);
293 platform_base_freq = 75000000;
294 platform_base_drift = -1;
295 }
296 if (!proc_ratio.den)
297 proc_ratio.den = 1;
298 if (!itc_ratio.den)
299 itc_ratio.den = 1;
300
301 itc_freq = (platform_base_freq*itc_ratio.num)/itc_ratio.den;
302
303 local_cpu_data->itm_delta = (itc_freq + HZ/2) / HZ;
304 printk(KERN_DEBUG "CPU %d: base freq=%lu.%03luMHz, ITC ratio=%u/%u, "
305 "ITC freq=%lu.%03luMHz", smp_processor_id(),
306 platform_base_freq / 1000000, (platform_base_freq / 1000) % 1000,
307 itc_ratio.num, itc_ratio.den, itc_freq / 1000000, (itc_freq / 1000) % 1000);
308
309 if (platform_base_drift != -1) {
310 itc_drift = platform_base_drift*itc_ratio.num/itc_ratio.den;
311 printk("+/-%ldppm\n", itc_drift);
312 } else {
313 itc_drift = -1;
314 printk("\n");
315 }
316
317 local_cpu_data->proc_freq = (platform_base_freq*proc_ratio.num)/proc_ratio.den;
318 local_cpu_data->itc_freq = itc_freq;
319 local_cpu_data->cyc_per_usec = (itc_freq + USEC_PER_SEC/2) / USEC_PER_SEC;
320 local_cpu_data->nsec_per_cyc = ((NSEC_PER_SEC<<IA64_NSEC_PER_CYC_SHIFT)
321 + itc_freq/2)/itc_freq;
322
323 if (!(sal_platform_features & IA64_SAL_PLATFORM_FEATURE_ITC_DRIFT)) {
324#ifdef CONFIG_SMP
325
326
327
328
329
330
331
332
333
334
335 if (!nojitter)
336 itc_jitter_data.itc_jitter = 1;
337#endif
338 } else
339
340
341
342
343
344
345
346
347
348
349
350
351
352 clocksource_itc.rating = 50;
353
354 paravirt_init_missing_ticks_accounting(smp_processor_id());
355
356
357 touch_softlockup_watchdog();
358
359
360 ia64_cpu_local_tick();
361
362 if (!itc_clocksource) {
363 clocksource_register_hz(&clocksource_itc,
364 local_cpu_data->itc_freq);
365 itc_clocksource = &clocksource_itc;
366 }
367}
368
369static cycle_t itc_get_cycles(struct clocksource *cs)
370{
371 unsigned long lcycle, now, ret;
372
373 if (!itc_jitter_data.itc_jitter)
374 return get_cycles();
375
376 lcycle = itc_jitter_data.itc_lastcycle;
377 now = get_cycles();
378 if (lcycle && time_after(lcycle, now))
379 return lcycle;
380
381
382
383
384
385
386
387 ret = cmpxchg(&itc_jitter_data.itc_lastcycle, lcycle, now);
388 if (unlikely(ret != lcycle))
389 return ret;
390
391 return now;
392}
393
394
395static struct irqaction timer_irqaction = {
396 .handler = timer_interrupt,
397 .flags = IRQF_DISABLED | IRQF_IRQPOLL,
398 .name = "timer"
399};
400
401static struct platform_device rtc_efi_dev = {
402 .name = "rtc-efi",
403 .id = -1,
404};
405
406static int __init rtc_init(void)
407{
408 if (platform_device_register(&rtc_efi_dev) < 0)
409 printk(KERN_ERR "unable to register rtc device...\n");
410
411
412 return 0;
413}
414module_init(rtc_init);
415
416void read_persistent_clock(struct timespec *ts)
417{
418 efi_gettimeofday(ts);
419}
420
421void __init
422time_init (void)
423{
424 register_percpu_irq(IA64_TIMER_VECTOR, &timer_irqaction);
425 ia64_init_itm();
426}
427
428
429
430
431
432
433static void
434ia64_itc_udelay (unsigned long usecs)
435{
436 unsigned long start = ia64_get_itc();
437 unsigned long end = start + usecs*local_cpu_data->cyc_per_usec;
438
439 while (time_before(ia64_get_itc(), end))
440 cpu_relax();
441}
442
443void (*ia64_udelay)(unsigned long usecs) = &ia64_itc_udelay;
444
445void
446udelay (unsigned long usecs)
447{
448 (*ia64_udelay)(usecs);
449}
450EXPORT_SYMBOL(udelay);
451
452
453void update_vsyscall_tz(void)
454{
455}
456
457void update_vsyscall(struct timespec *wall, struct timespec *wtm,
458 struct clocksource *c, u32 mult)
459{
460 write_seqcount_begin(&fsyscall_gtod_data.seq);
461
462
463 fsyscall_gtod_data.clk_mask = c->mask;
464 fsyscall_gtod_data.clk_mult = mult;
465 fsyscall_gtod_data.clk_shift = c->shift;
466 fsyscall_gtod_data.clk_fsys_mmio = c->archdata.fsys_mmio;
467 fsyscall_gtod_data.clk_cycle_last = c->cycle_last;
468
469
470 fsyscall_gtod_data.wall_time.tv_sec = wall->tv_sec;
471 fsyscall_gtod_data.wall_time.tv_nsec = wall->tv_nsec;
472 fsyscall_gtod_data.monotonic_time.tv_sec = wtm->tv_sec
473 + wall->tv_sec;
474 fsyscall_gtod_data.monotonic_time.tv_nsec = wtm->tv_nsec
475 + wall->tv_nsec;
476
477
478 while (fsyscall_gtod_data.monotonic_time.tv_nsec >= NSEC_PER_SEC) {
479 fsyscall_gtod_data.monotonic_time.tv_nsec -= NSEC_PER_SEC;
480 fsyscall_gtod_data.monotonic_time.tv_sec++;
481 }
482
483 write_seqcount_end(&fsyscall_gtod_data.seq);
484}
485
486