1 /*
2  * linux/arch/cris/kernel/fasttimer.c
3  *
4  * Fast timers for ETRAX100/ETRAX100LX
5  *
6  * Copyright (C) 2000-2007 Axis Communications AB, Lund, Sweden
7  */
8 
9 #include <linux/errno.h>
10 #include <linux/sched.h>
11 #include <linux/kernel.h>
12 #include <linux/param.h>
13 #include <linux/string.h>
14 #include <linux/mm.h>
15 #include <linux/vmalloc.h>
16 #include <linux/interrupt.h>
17 #include <linux/time.h>
18 #include <linux/delay.h>
19 
20 #include <asm/segment.h>
21 #include <asm/io.h>
22 #include <asm/irq.h>
23 #include <asm/delay.h>
24 #include <asm/rtc.h>
25 
26 
27 #include <arch/svinto.h>
28 #include <asm/fasttimer.h>
29 #include <linux/proc_fs.h>
30 
31 
32 #define DEBUG_LOG_INCLUDED
33 #define FAST_TIMER_LOG
34 /* #define FAST_TIMER_TEST */
35 
36 #define FAST_TIMER_SANITY_CHECKS
37 
38 #ifdef FAST_TIMER_SANITY_CHECKS
39 static int sanity_failed;
40 #endif
41 
42 #define D1(x)
43 #define D2(x)
44 #define DP(x)
45 
46 static unsigned int fast_timer_running;
47 static unsigned int fast_timers_added;
48 static unsigned int fast_timers_started;
49 static unsigned int fast_timers_expired;
50 static unsigned int fast_timers_deleted;
51 static unsigned int fast_timer_is_init;
52 static unsigned int fast_timer_ints;
53 
54 struct fast_timer *fast_timer_list = NULL;
55 
56 #ifdef DEBUG_LOG_INCLUDED
57 #define DEBUG_LOG_MAX 128
58 static const char * debug_log_string[DEBUG_LOG_MAX];
59 static unsigned long debug_log_value[DEBUG_LOG_MAX];
60 static unsigned int debug_log_cnt;
61 static unsigned int debug_log_cnt_wrapped;
62 
63 #define DEBUG_LOG(string, value) \
64 { \
65   unsigned long log_flags; \
66   local_irq_save(log_flags); \
67   debug_log_string[debug_log_cnt] = (string); \
68   debug_log_value[debug_log_cnt] = (unsigned long)(value); \
69   if (++debug_log_cnt >= DEBUG_LOG_MAX) \
70   { \
71     debug_log_cnt = debug_log_cnt % DEBUG_LOG_MAX; \
72     debug_log_cnt_wrapped = 1; \
73   } \
74   local_irq_restore(log_flags); \
75 }
76 #else
77 #define DEBUG_LOG(string, value)
78 #endif
79 
80 
81 /* The frequencies for index = clkselx number in R_TIMER_CTRL */
82 #define NUM_TIMER_FREQ 15
83 #define MAX_USABLE_TIMER_FREQ 7
84 #define MAX_DELAY_US  853333L
85 const unsigned long timer_freq_100[NUM_TIMER_FREQ] =
86 {
87   3,   /* 0 3333 - 853333 us */
88   6,   /* 1 1666 - 426666 us */
89   12,  /* 2  833 - 213333 us */
90   24,  /* 3  416 - 106666 us */
91   48,  /* 4  208 -  53333 us */
92   96,  /* 5  104 -  26666 us */
93   192, /* 6   52 -  13333 us */
94   384, /* 7   26 -   6666 us */
95   576,
96   1152,
97   2304,
98   4608,
99   9216,
100   18432,
101   62500,
102   /* 15 = cascade */
103 };
104 #define NUM_TIMER_STATS 16
105 #ifdef FAST_TIMER_LOG
106 struct fast_timer timer_added_log[NUM_TIMER_STATS];
107 struct fast_timer timer_started_log[NUM_TIMER_STATS];
108 struct fast_timer timer_expired_log[NUM_TIMER_STATS];
109 #endif
110 
111 int timer_div_settings[NUM_TIMER_STATS];
112 int timer_freq_settings[NUM_TIMER_STATS];
113 int timer_delay_settings[NUM_TIMER_STATS];
114 
115 /* Not true gettimeofday, only checks the jiffies (uptime) + useconds */
do_gettimeofday_fast(struct fasttime_t * tv)116 inline void do_gettimeofday_fast(struct fasttime_t *tv)
117 {
118 	tv->tv_jiff = jiffies;
119 	tv->tv_usec = GET_JIFFIES_USEC();
120 }
121 
fasttime_cmp(struct fasttime_t * t0,struct fasttime_t * t1)122 inline int fasttime_cmp(struct fasttime_t *t0, struct fasttime_t *t1)
123 {
124 	/* Compare jiffies. Takes care of wrapping */
125 	if (time_before(t0->tv_jiff, t1->tv_jiff))
126 		return -1;
127 	else if (time_after(t0->tv_jiff, t1->tv_jiff))
128 		return 1;
129 
130 	/* Compare us */
131 	if (t0->tv_usec < t1->tv_usec)
132 		return -1;
133 	else if (t0->tv_usec > t1->tv_usec)
134 		return 1;
135 	return 0;
136 }
137 
start_timer1(unsigned long delay_us)138 inline void start_timer1(unsigned long delay_us)
139 {
140   int freq_index = 0; /* This is the lowest resolution */
141   unsigned long upper_limit = MAX_DELAY_US;
142 
143   unsigned long div;
144   /* Start/Restart the timer to the new shorter value */
145   /* t = 1/freq = 1/19200 = 53us
146    * T=div*t,  div = T/t = delay_us*freq/1000000
147    */
148 #if 1 /* Adaptive timer settings */
149   while (delay_us < upper_limit && freq_index < MAX_USABLE_TIMER_FREQ)
150   {
151     freq_index++;
152     upper_limit >>= 1; /* Divide by 2 using shift */
153   }
154   if (freq_index > 0)
155   {
156     freq_index--;
157   }
158 #else
159   freq_index = 6;
160 #endif
161   div = delay_us * timer_freq_100[freq_index]/10000;
162   if (div < 2)
163   {
164     /* Maybe increase timer freq? */
165     div = 2;
166   }
167   if (div > 255)
168   {
169     div = 0; /* This means 256, the max the timer takes */
170     /* If a longer timeout than the timer can handle is used,
171      * then we must restart it when it goes off.
172      */
173   }
174 
175   timer_div_settings[fast_timers_started % NUM_TIMER_STATS] = div;
176   timer_freq_settings[fast_timers_started % NUM_TIMER_STATS] = freq_index;
177   timer_delay_settings[fast_timers_started % NUM_TIMER_STATS] = delay_us;
178 
179 	D1(printk(KERN_DEBUG "start_timer1 : %d us freq: %i div: %i\n",
180             delay_us, freq_index, div));
181   /* Clear timer1 irq */
182   *R_IRQ_MASK0_CLR = IO_STATE(R_IRQ_MASK0_CLR, timer1, clr);
183 
184   /* Set timer values */
185   *R_TIMER_CTRL = r_timer_ctrl_shadow =
186     (r_timer_ctrl_shadow &
187      ~IO_MASK(R_TIMER_CTRL, timerdiv1) &
188      ~IO_MASK(R_TIMER_CTRL, tm1) &
189      ~IO_MASK(R_TIMER_CTRL, clksel1)) |
190     IO_FIELD(R_TIMER_CTRL, timerdiv1, div) |
191     IO_STATE(R_TIMER_CTRL, tm1, stop_ld) |
192     IO_FIELD(R_TIMER_CTRL, clksel1, freq_index ); /* 6=c19k2Hz */
193 
194   /* Ack interrupt */
195   *R_TIMER_CTRL =  r_timer_ctrl_shadow |
196     IO_STATE(R_TIMER_CTRL, i1, clr);
197 
198   /* Start timer */
199   *R_TIMER_CTRL = r_timer_ctrl_shadow =
200     (r_timer_ctrl_shadow & ~IO_MASK(R_TIMER_CTRL, tm1)) |
201     IO_STATE(R_TIMER_CTRL, tm1, run);
202 
203   /* Enable timer1 irq */
204   *R_IRQ_MASK0_SET = IO_STATE(R_IRQ_MASK0_SET, timer1, set);
205   fast_timers_started++;
206   fast_timer_running = 1;
207 }
208 
209 /* In version 1.4 this function takes 27 - 50 us */
start_one_shot_timer(struct fast_timer * t,fast_timer_function_type * function,unsigned long data,unsigned long delay_us,const char * name)210 void start_one_shot_timer(struct fast_timer *t,
211                           fast_timer_function_type *function,
212                           unsigned long data,
213                           unsigned long delay_us,
214                           const char *name)
215 {
216   unsigned long flags;
217   struct fast_timer *tmp;
218 
219   D1(printk("sft %s %d us\n", name, delay_us));
220 
221   local_irq_save(flags);
222 
223   do_gettimeofday_fast(&t->tv_set);
224   tmp = fast_timer_list;
225 
226 #ifdef FAST_TIMER_SANITY_CHECKS
227 	/* Check so this is not in the list already... */
228 	while (tmp != NULL) {
229 		if (tmp == t) {
230 			printk(KERN_WARNING "timer name: %s data: "
231 				"0x%08lX already in list!\n", name, data);
232 			sanity_failed++;
233 			goto done;
234 		} else
235 			tmp = tmp->next;
236 	}
237 	tmp = fast_timer_list;
238 #endif
239 
240   t->delay_us = delay_us;
241   t->function = function;
242   t->data = data;
243   t->name = name;
244 
245   t->tv_expires.tv_usec = t->tv_set.tv_usec + delay_us % 1000000;
246 	t->tv_expires.tv_jiff = t->tv_set.tv_jiff + delay_us / 1000000 / HZ;
247   if (t->tv_expires.tv_usec > 1000000)
248   {
249     t->tv_expires.tv_usec -= 1000000;
250 		t->tv_expires.tv_jiff += HZ;
251   }
252 #ifdef FAST_TIMER_LOG
253   timer_added_log[fast_timers_added % NUM_TIMER_STATS] = *t;
254 #endif
255   fast_timers_added++;
256 
257   /* Check if this should timeout before anything else */
258 	if (tmp == NULL || fasttime_cmp(&t->tv_expires, &tmp->tv_expires) < 0)
259   {
260     /* Put first in list and modify the timer value */
261     t->prev = NULL;
262     t->next = fast_timer_list;
263     if (fast_timer_list)
264     {
265       fast_timer_list->prev = t;
266     }
267     fast_timer_list = t;
268 #ifdef FAST_TIMER_LOG
269     timer_started_log[fast_timers_started % NUM_TIMER_STATS] = *t;
270 #endif
271     start_timer1(delay_us);
272   } else {
273     /* Put in correct place in list */
274 		while (tmp->next && fasttime_cmp(&t->tv_expires,
275 				&tmp->next->tv_expires) > 0)
276     {
277       tmp = tmp->next;
278     }
279     /* Insert t after tmp */
280     t->prev = tmp;
281     t->next = tmp->next;
282     if (tmp->next)
283     {
284       tmp->next->prev = t;
285     }
286     tmp->next = t;
287   }
288 
289   D2(printk("start_one_shot_timer: %d us done\n", delay_us));
290 
291 done:
292   local_irq_restore(flags);
293 } /* start_one_shot_timer */
294 
fast_timer_pending(const struct fast_timer * t)295 static inline int fast_timer_pending (const struct fast_timer * t)
296 {
297   return (t->next != NULL) || (t->prev != NULL) || (t == fast_timer_list);
298 }
299 
detach_fast_timer(struct fast_timer * t)300 static inline int detach_fast_timer (struct fast_timer *t)
301 {
302   struct fast_timer *next, *prev;
303   if (!fast_timer_pending(t))
304     return 0;
305   next = t->next;
306   prev = t->prev;
307   if (next)
308     next->prev = prev;
309   if (prev)
310     prev->next = next;
311   else
312     fast_timer_list = next;
313   fast_timers_deleted++;
314   return 1;
315 }
316 
del_fast_timer(struct fast_timer * t)317 int del_fast_timer(struct fast_timer * t)
318 {
319   unsigned long flags;
320   int ret;
321 
322   local_irq_save(flags);
323   ret = detach_fast_timer(t);
324   t->next = t->prev = NULL;
325   local_irq_restore(flags);
326   return ret;
327 } /* del_fast_timer */
328 
329 
330 /* Interrupt routines or functions called in interrupt context */
331 
332 /* Timer 1 interrupt handler */
333 
334 static irqreturn_t
timer1_handler(int irq,void * dev_id)335 timer1_handler(int irq, void *dev_id)
336 {
337   struct fast_timer *t;
338   unsigned long flags;
339 
340 	/* We keep interrupts disabled not only when we modify the
341 	 * fast timer list, but any time we hold a reference to a
342 	 * timer in the list, since del_fast_timer may be called
343 	 * from (another) interrupt context.  Thus, the only time
344 	 * when interrupts are enabled is when calling the timer
345 	 * callback function.
346 	 */
347   local_irq_save(flags);
348 
349   /* Clear timer1 irq */
350   *R_IRQ_MASK0_CLR = IO_STATE(R_IRQ_MASK0_CLR, timer1, clr);
351 
352   /* First stop timer, then ack interrupt */
353   /* Stop timer */
354   *R_TIMER_CTRL = r_timer_ctrl_shadow =
355     (r_timer_ctrl_shadow & ~IO_MASK(R_TIMER_CTRL, tm1)) |
356     IO_STATE(R_TIMER_CTRL, tm1, stop_ld);
357 
358   /* Ack interrupt */
359   *R_TIMER_CTRL =  r_timer_ctrl_shadow | IO_STATE(R_TIMER_CTRL, i1, clr);
360 
361   fast_timer_running = 0;
362   fast_timer_ints++;
363 
364   t = fast_timer_list;
365   while (t)
366   {
367 		struct fasttime_t tv;
368 		fast_timer_function_type *f;
369 		unsigned long d;
370 
371     /* Has it really expired? */
372     do_gettimeofday_fast(&tv);
373 		D1(printk(KERN_DEBUG "t: %is %06ius\n",
374 			tv.tv_jiff, tv.tv_usec));
375 
376 		if (fasttime_cmp(&t->tv_expires, &tv) <= 0)
377     {
378       /* Yes it has expired */
379 #ifdef FAST_TIMER_LOG
380       timer_expired_log[fast_timers_expired % NUM_TIMER_STATS] = *t;
381 #endif
382       fast_timers_expired++;
383 
384       /* Remove this timer before call, since it may reuse the timer */
385       if (t->prev)
386       {
387         t->prev->next = t->next;
388       }
389       else
390       {
391         fast_timer_list = t->next;
392       }
393       if (t->next)
394       {
395         t->next->prev = t->prev;
396       }
397       t->prev = NULL;
398       t->next = NULL;
399 
400 			/* Save function callback data before enabling
401 			 * interrupts, since the timer may be removed and
402 			 * we don't know how it was allocated
403 			 * (e.g. ->function and ->data may become overwritten
404 			 * after deletion if the timer was stack-allocated).
405 			 */
406 			f = t->function;
407 			d = t->data;
408 
409 			if (f != NULL) {
410 				/* Run callback with interrupts enabled. */
411 				local_irq_restore(flags);
412 				f(d);
413 				local_irq_save(flags);
414 			} else
415         DEBUG_LOG("!timer1 %i function==NULL!\n", fast_timer_ints);
416     }
417     else
418     {
419       /* Timer is to early, let's set it again using the normal routines */
420       D1(printk(".\n"));
421     }
422 
423     if ((t = fast_timer_list) != NULL)
424     {
425       /* Start next timer.. */
426 			long us = 0;
427 			struct fasttime_t tv;
428 
429       do_gettimeofday_fast(&tv);
430 
431 			/* time_after_eq takes care of wrapping */
432 			if (time_after_eq(t->tv_expires.tv_jiff, tv.tv_jiff))
433 				us = ((t->tv_expires.tv_jiff - tv.tv_jiff) *
434 					1000000 / HZ + t->tv_expires.tv_usec -
435 					tv.tv_usec);
436 
437       if (us > 0)
438       {
439         if (!fast_timer_running)
440         {
441 #ifdef FAST_TIMER_LOG
442           timer_started_log[fast_timers_started % NUM_TIMER_STATS] = *t;
443 #endif
444           start_timer1(us);
445         }
446         break;
447       }
448       else
449       {
450         /* Timer already expired, let's handle it better late than never.
451          * The normal loop handles it
452          */
453         D1(printk("e! %d\n", us));
454       }
455     }
456   }
457 
458 	local_irq_restore(flags);
459 
460   if (!t)
461   {
462     D1(printk("t1 stop!\n"));
463   }
464 
465   return IRQ_HANDLED;
466 }
467 
wake_up_func(unsigned long data)468 static void wake_up_func(unsigned long data)
469 {
470   wait_queue_head_t *sleep_wait_p = (wait_queue_head_t *)data;
471   wake_up(sleep_wait_p);
472 }
473 
474 
475 /* Useful API */
476 
schedule_usleep(unsigned long us)477 void schedule_usleep(unsigned long us)
478 {
479   struct fast_timer t;
480   wait_queue_head_t sleep_wait;
481   init_waitqueue_head(&sleep_wait);
482 
483   D1(printk("schedule_usleep(%d)\n", us));
484   start_one_shot_timer(&t, wake_up_func, (unsigned long)&sleep_wait, us,
485                        "usleep");
486 	/* Uninterruptible sleep on the fast timer. (The condition is somewhat
487 	 * redundant since the timer is what wakes us up.) */
488 	wait_event(sleep_wait, !fast_timer_pending(&t));
489 
490   D1(printk("done schedule_usleep(%d)\n", us));
491 }
492 
493 #ifdef CONFIG_PROC_FS
494 static int proc_fasttimer_read(char *buf, char **start, off_t offset, int len
495                        ,int *eof, void *data_unused);
496 static struct proc_dir_entry *fasttimer_proc_entry;
497 #endif /* CONFIG_PROC_FS */
498 
499 #ifdef CONFIG_PROC_FS
500 
501 /* This value is very much based on testing */
502 #define BIG_BUF_SIZE (500 + NUM_TIMER_STATS * 300)
503 
proc_fasttimer_read(char * buf,char ** start,off_t offset,int len,int * eof,void * data_unused)504 static int proc_fasttimer_read(char *buf, char **start, off_t offset, int len
505                        ,int *eof, void *data_unused)
506 {
507   unsigned long flags;
508   int i = 0;
509   int num_to_show;
510 	struct fasttime_t tv;
511   struct fast_timer *t, *nextt;
512   static char *bigbuf = NULL;
513   static unsigned long used;
514 
515   if (!bigbuf && !(bigbuf = vmalloc(BIG_BUF_SIZE)))
516   {
517     used = 0;
518 	if (buf)
519 		buf[0] = '\0';
520     return 0;
521   }
522 
523   if (!offset || !used)
524   {
525     do_gettimeofday_fast(&tv);
526 
527     used = 0;
528     used += sprintf(bigbuf + used, "Fast timers added:     %i\n",
529                     fast_timers_added);
530     used += sprintf(bigbuf + used, "Fast timers started:   %i\n",
531                     fast_timers_started);
532     used += sprintf(bigbuf + used, "Fast timer interrupts: %i\n",
533                     fast_timer_ints);
534     used += sprintf(bigbuf + used, "Fast timers expired:   %i\n",
535                     fast_timers_expired);
536     used += sprintf(bigbuf + used, "Fast timers deleted:   %i\n",
537                     fast_timers_deleted);
538     used += sprintf(bigbuf + used, "Fast timer running:    %s\n",
539                     fast_timer_running ? "yes" : "no");
540     used += sprintf(bigbuf + used, "Current time:          %lu.%06lu\n",
541 			(unsigned long)tv.tv_jiff,
542                     (unsigned long)tv.tv_usec);
543 #ifdef FAST_TIMER_SANITY_CHECKS
544     used += sprintf(bigbuf + used, "Sanity failed:         %i\n",
545                     sanity_failed);
546 #endif
547     used += sprintf(bigbuf + used, "\n");
548 
549 #ifdef DEBUG_LOG_INCLUDED
550     {
551       int end_i = debug_log_cnt;
552       i = 0;
553 
554       if (debug_log_cnt_wrapped)
555       {
556         i = debug_log_cnt;
557       }
558 
559       while ((i != end_i || (debug_log_cnt_wrapped && !used)) &&
560              used+100 < BIG_BUF_SIZE)
561       {
562         used += sprintf(bigbuf + used, debug_log_string[i],
563                         debug_log_value[i]);
564         i = (i+1) % DEBUG_LOG_MAX;
565       }
566     }
567     used += sprintf(bigbuf + used, "\n");
568 #endif
569 
570     num_to_show = (fast_timers_started < NUM_TIMER_STATS ? fast_timers_started:
571                    NUM_TIMER_STATS);
572     used += sprintf(bigbuf + used, "Timers started: %i\n", fast_timers_started);
573     for (i = 0; i < num_to_show && (used+100 < BIG_BUF_SIZE) ; i++)
574     {
575       int cur = (fast_timers_started - i - 1) % NUM_TIMER_STATS;
576 
577 #if 1 //ndef FAST_TIMER_LOG
578       used += sprintf(bigbuf + used, "div: %i freq: %i delay: %i"
579                       "\n",
580                       timer_div_settings[cur],
581                       timer_freq_settings[cur],
582                       timer_delay_settings[cur]
583                       );
584 #endif
585 #ifdef FAST_TIMER_LOG
586       t = &timer_started_log[cur];
587       used += sprintf(bigbuf + used, "%-14s s: %6lu.%06lu e: %6lu.%06lu "
588                       "d: %6li us data: 0x%08lX"
589                       "\n",
590                       t->name,
591 			(unsigned long)t->tv_set.tv_jiff,
592                       (unsigned long)t->tv_set.tv_usec,
593 			(unsigned long)t->tv_expires.tv_jiff,
594                       (unsigned long)t->tv_expires.tv_usec,
595                       t->delay_us,
596                       t->data
597                       );
598 #endif
599     }
600     used += sprintf(bigbuf + used, "\n");
601 
602 #ifdef FAST_TIMER_LOG
603     num_to_show = (fast_timers_added < NUM_TIMER_STATS ? fast_timers_added:
604                    NUM_TIMER_STATS);
605     used += sprintf(bigbuf + used, "Timers added: %i\n", fast_timers_added);
606     for (i = 0; i < num_to_show && (used+100 < BIG_BUF_SIZE); i++)
607     {
608       t = &timer_added_log[(fast_timers_added - i - 1) % NUM_TIMER_STATS];
609       used += sprintf(bigbuf + used, "%-14s s: %6lu.%06lu e: %6lu.%06lu "
610                       "d: %6li us data: 0x%08lX"
611                       "\n",
612                       t->name,
613 			(unsigned long)t->tv_set.tv_jiff,
614                       (unsigned long)t->tv_set.tv_usec,
615 			(unsigned long)t->tv_expires.tv_jiff,
616                       (unsigned long)t->tv_expires.tv_usec,
617                       t->delay_us,
618                       t->data
619                       );
620     }
621     used += sprintf(bigbuf + used, "\n");
622 
623     num_to_show = (fast_timers_expired < NUM_TIMER_STATS ? fast_timers_expired:
624                    NUM_TIMER_STATS);
625     used += sprintf(bigbuf + used, "Timers expired: %i\n", fast_timers_expired);
626     for (i = 0; i < num_to_show && (used+100 < BIG_BUF_SIZE); i++)
627     {
628       t = &timer_expired_log[(fast_timers_expired - i - 1) % NUM_TIMER_STATS];
629       used += sprintf(bigbuf + used, "%-14s s: %6lu.%06lu e: %6lu.%06lu "
630                       "d: %6li us data: 0x%08lX"
631                       "\n",
632                       t->name,
633 			(unsigned long)t->tv_set.tv_jiff,
634                       (unsigned long)t->tv_set.tv_usec,
635 			(unsigned long)t->tv_expires.tv_jiff,
636                       (unsigned long)t->tv_expires.tv_usec,
637                       t->delay_us,
638                       t->data
639                       );
640     }
641     used += sprintf(bigbuf + used, "\n");
642 #endif
643 
644     used += sprintf(bigbuf + used, "Active timers:\n");
645     local_irq_save(flags);
646     t = fast_timer_list;
647     while (t != NULL && (used+100 < BIG_BUF_SIZE))
648     {
649       nextt = t->next;
650       local_irq_restore(flags);
651       used += sprintf(bigbuf + used, "%-14s s: %6lu.%06lu e: %6lu.%06lu "
652                       "d: %6li us data: 0x%08lX"
653 /*                      " func: 0x%08lX" */
654                       "\n",
655                       t->name,
656 			(unsigned long)t->tv_set.tv_jiff,
657                       (unsigned long)t->tv_set.tv_usec,
658 			(unsigned long)t->tv_expires.tv_jiff,
659                       (unsigned long)t->tv_expires.tv_usec,
660                       t->delay_us,
661                       t->data
662 /*                      , t->function */
663                       );
664 	local_irq_save(flags);
665       if (t->next != nextt)
666       {
667         printk(KERN_WARNING "timer removed!\n");
668       }
669       t = nextt;
670     }
671     local_irq_restore(flags);
672   }
673 
674   if (used - offset < len)
675   {
676     len = used - offset;
677   }
678 
679   memcpy(buf, bigbuf + offset, len);
680   *start = buf;
681   *eof = 1;
682 
683   return len;
684 }
685 #endif /* PROC_FS */
686 
687 #ifdef FAST_TIMER_TEST
688 static volatile unsigned long i = 0;
689 static volatile int num_test_timeout = 0;
690 static struct fast_timer tr[10];
691 static int exp_num[10];
692 
693 static struct fasttime_t tv_exp[100];
694 
test_timeout(unsigned long data)695 static void test_timeout(unsigned long data)
696 {
697   do_gettimeofday_fast(&tv_exp[data]);
698   exp_num[data] = num_test_timeout;
699 
700   num_test_timeout++;
701 }
702 
test_timeout1(unsigned long data)703 static void test_timeout1(unsigned long data)
704 {
705   do_gettimeofday_fast(&tv_exp[data]);
706   exp_num[data] = num_test_timeout;
707   if (data < 7)
708   {
709     start_one_shot_timer(&tr[i], test_timeout1, i, 1000, "timeout1");
710     i++;
711   }
712   num_test_timeout++;
713 }
714 
715 DP(
716 static char buf0[2000];
717 static char buf1[2000];
718 static char buf2[2000];
719 static char buf3[2000];
720 static char buf4[2000];
721 );
722 
723 static char buf5[6000];
724 static int j_u[1000];
725 
fast_timer_test(void)726 static void fast_timer_test(void)
727 {
728   int prev_num;
729   int j;
730 
731 	struct fasttime_t tv, tv0, tv1, tv2;
732 
733   printk("fast_timer_test() start\n");
734   do_gettimeofday_fast(&tv);
735 
736   for (j = 0; j < 1000; j++)
737   {
738     j_u[j] = GET_JIFFIES_USEC();
739   }
740   for (j = 0; j < 100; j++)
741   {
742     do_gettimeofday_fast(&tv_exp[j]);
743   }
744 	printk(KERN_DEBUG "fast_timer_test() %is %06i\n",
745 		tv.tv_jiff, tv.tv_usec);
746 
747   for (j = 0; j < 1000; j++)
748   {
749     printk("%i %i %i %i %i\n",j_u[j], j_u[j+1], j_u[j+2], j_u[j+3], j_u[j+4]);
750     j += 4;
751   }
752   for (j = 0; j < 100; j++)
753   {
754 		printk(KERN_DEBUG "%i.%i %i.%i %i.%i %i.%i %i.%i\n",
755 			tv_exp[j].tv_jiff, tv_exp[j].tv_usec,
756 			tv_exp[j+1].tv_jiff, tv_exp[j+1].tv_usec,
757 			tv_exp[j+2].tv_jiff, tv_exp[j+2].tv_usec,
758 			tv_exp[j+3].tv_jiff, tv_exp[j+3].tv_usec,
759 			tv_exp[j+4].tv_jiff, tv_exp[j+4].tv_usec);
760     j += 4;
761   }
762   do_gettimeofday_fast(&tv0);
763   start_one_shot_timer(&tr[i], test_timeout, i, 50000, "test0");
764   DP(proc_fasttimer_read(buf0, NULL, 0, 0, 0));
765   i++;
766   start_one_shot_timer(&tr[i], test_timeout, i, 70000, "test1");
767   DP(proc_fasttimer_read(buf1, NULL, 0, 0, 0));
768   i++;
769   start_one_shot_timer(&tr[i], test_timeout, i, 40000, "test2");
770   DP(proc_fasttimer_read(buf2, NULL, 0, 0, 0));
771   i++;
772   start_one_shot_timer(&tr[i], test_timeout, i, 60000, "test3");
773   DP(proc_fasttimer_read(buf3, NULL, 0, 0, 0));
774   i++;
775   start_one_shot_timer(&tr[i], test_timeout1, i, 55000, "test4xx");
776   DP(proc_fasttimer_read(buf4, NULL, 0, 0, 0));
777   i++;
778   do_gettimeofday_fast(&tv1);
779 
780   proc_fasttimer_read(buf5, NULL, 0, 0, 0);
781 
782   prev_num = num_test_timeout;
783   while (num_test_timeout < i)
784   {
785     if (num_test_timeout != prev_num)
786     {
787       prev_num = num_test_timeout;
788     }
789   }
790   do_gettimeofday_fast(&tv2);
791 	printk(KERN_DEBUG "Timers started    %is %06i\n",
792 		tv0.tv_jiff, tv0.tv_usec);
793 	printk(KERN_DEBUG "Timers started at %is %06i\n",
794 		tv1.tv_jiff, tv1.tv_usec);
795 	printk(KERN_DEBUG "Timers done       %is %06i\n",
796 		tv2.tv_jiff, tv2.tv_usec);
797   DP(printk("buf0:\n");
798      printk(buf0);
799      printk("buf1:\n");
800      printk(buf1);
801      printk("buf2:\n");
802      printk(buf2);
803      printk("buf3:\n");
804      printk(buf3);
805      printk("buf4:\n");
806      printk(buf4);
807   );
808   printk("buf5:\n");
809   printk(buf5);
810 
811   printk("timers set:\n");
812   for(j = 0; j<i; j++)
813   {
814     struct fast_timer *t = &tr[j];
815     printk("%-10s set: %6is %06ius exp: %6is %06ius "
816            "data: 0x%08X func: 0x%08X\n",
817            t->name,
818 			t->tv_set.tv_jiff,
819            t->tv_set.tv_usec,
820 			t->tv_expires.tv_jiff,
821            t->tv_expires.tv_usec,
822            t->data,
823            t->function
824            );
825 
826     printk("           del: %6ius     did exp: %6is %06ius as #%i error: %6li\n",
827            t->delay_us,
828 			tv_exp[j].tv_jiff,
829            tv_exp[j].tv_usec,
830            exp_num[j],
831 			(tv_exp[j].tv_jiff - t->tv_expires.tv_jiff) *
832 				1000000 + tv_exp[j].tv_usec -
833 				t->tv_expires.tv_usec);
834   }
835   proc_fasttimer_read(buf5, NULL, 0, 0, 0);
836   printk("buf5 after all done:\n");
837   printk(buf5);
838   printk("fast_timer_test() done\n");
839 }
840 #endif
841 
842 
fast_timer_init(void)843 int fast_timer_init(void)
844 {
845   /* For some reason, request_irq() hangs when called froom time_init() */
846   if (!fast_timer_is_init)
847   {
848 #if 0 && defined(FAST_TIMER_TEST)
849     int i;
850 #endif
851 
852     printk(KERN_INFO "fast_timer_init()\n");
853 
854 #if 0 && defined(FAST_TIMER_TEST)
855     for (i = 0; i <= TIMER0_DIV; i++)
856     {
857       /* We must be careful not to get overflow... */
858       printk("%3i %6u\n", i, timer0_value_us[i]);
859     }
860 #endif
861 #ifdef CONFIG_PROC_FS
862    if ((fasttimer_proc_entry = create_proc_entry( "fasttimer", 0, 0 )))
863      fasttimer_proc_entry->read_proc = proc_fasttimer_read;
864 #endif /* PROC_FS */
865     if(request_irq(TIMER1_IRQ_NBR, timer1_handler, 0,
866                    "fast timer int", NULL))
867     {
868       printk("err: timer1 irq\n");
869     }
870     fast_timer_is_init = 1;
871 #ifdef FAST_TIMER_TEST
872     printk("do test\n");
873     fast_timer_test();
874 #endif
875   }
876 	return 0;
877 }
878 __initcall(fast_timer_init);
879