linux/arch/cris/arch-v32/kernel/fasttimer.c
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   1/*
   2 * linux/arch/cris/kernel/fasttimer.c
   3 *
   4 * Fast timers for ETRAX FS
   5 *
   6 * Copyright (C) 2000-2006 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/vmalloc.h>
  15#include <linux/interrupt.h>
  16#include <linux/time.h>
  17#include <linux/delay.h>
  18
  19#include <asm/irq.h>
  20
  21#include <hwregs/reg_map.h>
  22#include <hwregs/reg_rdwr.h>
  23#include <hwregs/timer_defs.h>
  24#include <asm/fasttimer.h>
  25#include <linux/proc_fs.h>
  26
  27/*
  28 * timer0 is running at 100MHz and generating jiffies timer ticks
  29 * at 100 or 1000 HZ.
  30 * fasttimer gives an API that gives timers that expire "between" the jiffies
  31 * giving microsecond resolution (10 ns).
  32 * fasttimer uses reg_timer_rw_trig register to get interrupt when
  33 * r_time reaches a certain value.
  34 */
  35
  36
  37#define DEBUG_LOG_INCLUDED
  38#define FAST_TIMER_LOG
  39/* #define FAST_TIMER_TEST */
  40
  41#define FAST_TIMER_SANITY_CHECKS
  42
  43#ifdef FAST_TIMER_SANITY_CHECKS
  44static int sanity_failed;
  45#endif
  46
  47#define D1(x)
  48#define D2(x)
  49#define DP(x)
  50
  51static unsigned int fast_timer_running;
  52static unsigned int fast_timers_added;
  53static unsigned int fast_timers_started;
  54static unsigned int fast_timers_expired;
  55static unsigned int fast_timers_deleted;
  56static unsigned int fast_timer_is_init;
  57static unsigned int fast_timer_ints;
  58
  59struct fast_timer *fast_timer_list = NULL;
  60
  61#ifdef DEBUG_LOG_INCLUDED
  62#define DEBUG_LOG_MAX 128
  63static const char * debug_log_string[DEBUG_LOG_MAX];
  64static unsigned long debug_log_value[DEBUG_LOG_MAX];
  65static unsigned int debug_log_cnt;
  66static unsigned int debug_log_cnt_wrapped;
  67
  68#define DEBUG_LOG(string, value) \
  69{ \
  70  unsigned long log_flags; \
  71  local_irq_save(log_flags); \
  72  debug_log_string[debug_log_cnt] = (string); \
  73  debug_log_value[debug_log_cnt] = (unsigned long)(value); \
  74  if (++debug_log_cnt >= DEBUG_LOG_MAX) \
  75  { \
  76    debug_log_cnt = debug_log_cnt % DEBUG_LOG_MAX; \
  77    debug_log_cnt_wrapped = 1; \
  78  } \
  79  local_irq_restore(log_flags); \
  80}
  81#else
  82#define DEBUG_LOG(string, value)
  83#endif
  84
  85
  86#define NUM_TIMER_STATS 16
  87#ifdef FAST_TIMER_LOG
  88struct fast_timer timer_added_log[NUM_TIMER_STATS];
  89struct fast_timer timer_started_log[NUM_TIMER_STATS];
  90struct fast_timer timer_expired_log[NUM_TIMER_STATS];
  91#endif
  92
  93int timer_div_settings[NUM_TIMER_STATS];
  94int timer_delay_settings[NUM_TIMER_STATS];
  95
  96struct work_struct fast_work;
  97
  98static void
  99timer_trig_handler(struct work_struct *work);
 100
 101
 102
 103/* Not true gettimeofday, only checks the jiffies (uptime) + useconds */
 104inline void do_gettimeofday_fast(struct fasttime_t *tv)
 105{
 106        tv->tv_jiff = jiffies;
 107        tv->tv_usec = GET_JIFFIES_USEC();
 108}
 109
 110inline int fasttime_cmp(struct fasttime_t *t0, struct fasttime_t *t1)
 111{
 112        /* Compare jiffies. Takes care of wrapping */
 113        if (time_before(t0->tv_jiff, t1->tv_jiff))
 114                return -1;
 115        else if (time_after(t0->tv_jiff, t1->tv_jiff))
 116                return 1;
 117
 118        /* Compare us */
 119        if (t0->tv_usec < t1->tv_usec)
 120                return -1;
 121        else if (t0->tv_usec > t1->tv_usec)
 122                return 1;
 123        return 0;
 124}
 125
 126/* Called with ints off */
 127inline void start_timer_trig(unsigned long delay_us)
 128{
 129  reg_timer_rw_ack_intr ack_intr = { 0 };
 130  reg_timer_rw_intr_mask intr_mask;
 131  reg_timer_rw_trig trig;
 132  reg_timer_rw_trig_cfg trig_cfg = { 0 };
 133        reg_timer_r_time r_time0;
 134        reg_timer_r_time r_time1;
 135        unsigned char trig_wrap;
 136        unsigned char time_wrap;
 137
 138        r_time0 = REG_RD(timer, regi_timer0, r_time);
 139
 140  D1(printk("start_timer_trig : %d us freq: %i div: %i\n",
 141            delay_us, freq_index, div));
 142  /* Clear trig irq */
 143        intr_mask = REG_RD(timer, regi_timer0, rw_intr_mask);
 144  intr_mask.trig = 0;
 145        REG_WR(timer, regi_timer0, rw_intr_mask, intr_mask);
 146
 147        /* Set timer values and check if trigger wraps. */
 148        /* r_time is 100MHz (10 ns resolution) */
 149        trig_wrap = (trig = r_time0 + delay_us*(1000/10)) < r_time0;
 150
 151  timer_div_settings[fast_timers_started % NUM_TIMER_STATS] = trig;
 152  timer_delay_settings[fast_timers_started % NUM_TIMER_STATS] = delay_us;
 153
 154  /* Ack interrupt */
 155  ack_intr.trig = 1;
 156        REG_WR(timer, regi_timer0, rw_ack_intr, ack_intr);
 157
 158  /* Start timer */
 159        REG_WR(timer, regi_timer0, rw_trig, trig);
 160  trig_cfg.tmr = regk_timer_time;
 161        REG_WR(timer, regi_timer0, rw_trig_cfg, trig_cfg);
 162
 163  /* Check if we have already passed the trig time */
 164        r_time1 = REG_RD(timer, regi_timer0, r_time);
 165        time_wrap = r_time1 < r_time0;
 166
 167        if ((trig_wrap && !time_wrap) || (r_time1 < trig)) {
 168    /* No, Enable trig irq */
 169                intr_mask = REG_RD(timer, regi_timer0, rw_intr_mask);
 170    intr_mask.trig = 1;
 171                REG_WR(timer, regi_timer0, rw_intr_mask, intr_mask);
 172    fast_timers_started++;
 173    fast_timer_running = 1;
 174        } else {
 175    /* We have passed the time, disable trig point, ack intr */
 176    trig_cfg.tmr = regk_timer_off;
 177                REG_WR(timer, regi_timer0, rw_trig_cfg, trig_cfg);
 178                REG_WR(timer, regi_timer0, rw_ack_intr, ack_intr);
 179                /* call the int routine */
 180                INIT_WORK(&fast_work, timer_trig_handler);
 181                schedule_work(&fast_work);
 182  }
 183
 184}
 185
 186/* In version 1.4 this function takes 27 - 50 us */
 187void start_one_shot_timer(struct fast_timer *t,
 188                          fast_timer_function_type *function,
 189                          unsigned long data,
 190                          unsigned long delay_us,
 191                          const char *name)
 192{
 193  unsigned long flags;
 194  struct fast_timer *tmp;
 195
 196  D1(printk("sft %s %d us\n", name, delay_us));
 197
 198  local_irq_save(flags);
 199
 200  do_gettimeofday_fast(&t->tv_set);
 201  tmp = fast_timer_list;
 202
 203#ifdef FAST_TIMER_SANITY_CHECKS
 204        /* Check so this is not in the list already... */
 205        while (tmp != NULL) {
 206                if (tmp == t) {
 207                        printk(KERN_DEBUG
 208                                "timer name: %s data: 0x%08lX already "
 209                                "in list!\n", name, data);
 210                        sanity_failed++;
 211                        goto done;
 212                } else
 213                        tmp = tmp->next;
 214        }
 215        tmp = fast_timer_list;
 216#endif
 217
 218  t->delay_us = delay_us;
 219  t->function = function;
 220  t->data = data;
 221  t->name = name;
 222
 223  t->tv_expires.tv_usec = t->tv_set.tv_usec + delay_us % 1000000;
 224        t->tv_expires.tv_jiff = t->tv_set.tv_jiff + delay_us / 1000000 / HZ;
 225        if (t->tv_expires.tv_usec > 1000000) {
 226    t->tv_expires.tv_usec -= 1000000;
 227                t->tv_expires.tv_jiff += HZ;
 228  }
 229#ifdef FAST_TIMER_LOG
 230  timer_added_log[fast_timers_added % NUM_TIMER_STATS] = *t;
 231#endif
 232  fast_timers_added++;
 233
 234  /* Check if this should timeout before anything else */
 235  if (tmp == NULL || fasttime_cmp(&t->tv_expires, &tmp->tv_expires) < 0) {
 236    /* Put first in list and modify the timer value */
 237    t->prev = NULL;
 238    t->next = fast_timer_list;
 239    if (fast_timer_list)
 240      fast_timer_list->prev = t;
 241    fast_timer_list = t;
 242#ifdef FAST_TIMER_LOG
 243    timer_started_log[fast_timers_started % NUM_TIMER_STATS] = *t;
 244#endif
 245    start_timer_trig(delay_us);
 246  } else {
 247    /* Put in correct place in list */
 248    while (tmp->next &&
 249        fasttime_cmp(&t->tv_expires, &tmp->next->tv_expires) > 0)
 250      tmp = tmp->next;
 251    /* Insert t after tmp */
 252    t->prev = tmp;
 253    t->next = tmp->next;
 254    if (tmp->next)
 255    {
 256      tmp->next->prev = t;
 257    }
 258    tmp->next = t;
 259  }
 260
 261  D2(printk("start_one_shot_timer: %d us done\n", delay_us));
 262
 263done:
 264  local_irq_restore(flags);
 265} /* start_one_shot_timer */
 266
 267static inline int fast_timer_pending (const struct fast_timer * t)
 268{
 269  return (t->next != NULL) || (t->prev != NULL) || (t == fast_timer_list);
 270}
 271
 272static inline int detach_fast_timer (struct fast_timer *t)
 273{
 274  struct fast_timer *next, *prev;
 275  if (!fast_timer_pending(t))
 276    return 0;
 277  next = t->next;
 278  prev = t->prev;
 279  if (next)
 280    next->prev = prev;
 281  if (prev)
 282    prev->next = next;
 283  else
 284    fast_timer_list = next;
 285  fast_timers_deleted++;
 286  return 1;
 287}
 288
 289int del_fast_timer(struct fast_timer * t)
 290{
 291  unsigned long flags;
 292  int ret;
 293
 294  local_irq_save(flags);
 295  ret = detach_fast_timer(t);
 296  t->next = t->prev = NULL;
 297  local_irq_restore(flags);
 298  return ret;
 299} /* del_fast_timer */
 300
 301
 302/* Interrupt routines or functions called in interrupt context */
 303
 304/* Timer interrupt handler for trig interrupts */
 305
 306static irqreturn_t
 307timer_trig_interrupt(int irq, void *dev_id)
 308{
 309  reg_timer_r_masked_intr masked_intr;
 310  /* Check if the timer interrupt is for us (a trig int) */
 311        masked_intr = REG_RD(timer, regi_timer0, r_masked_intr);
 312  if (!masked_intr.trig)
 313    return IRQ_NONE;
 314        timer_trig_handler(NULL);
 315  return IRQ_HANDLED;
 316}
 317
 318static void timer_trig_handler(struct work_struct *work)
 319{
 320  reg_timer_rw_ack_intr ack_intr = { 0 };
 321  reg_timer_rw_intr_mask intr_mask;
 322  reg_timer_rw_trig_cfg trig_cfg = { 0 };
 323  struct fast_timer *t;
 324  unsigned long flags;
 325
 326        /* We keep interrupts disabled not only when we modify the
 327         * fast timer list, but any time we hold a reference to a
 328         * timer in the list, since del_fast_timer may be called
 329         * from (another) interrupt context.  Thus, the only time
 330         * when interrupts are enabled is when calling the timer
 331         * callback function.
 332         */
 333  local_irq_save(flags);
 334
 335  /* Clear timer trig interrupt */
 336        intr_mask = REG_RD(timer, regi_timer0, rw_intr_mask);
 337  intr_mask.trig = 0;
 338  REG_WR(timer, regi_timer0, rw_intr_mask, intr_mask);
 339
 340  /* First stop timer, then ack interrupt */
 341  /* Stop timer */
 342  trig_cfg.tmr = regk_timer_off;
 343        REG_WR(timer, regi_timer0, rw_trig_cfg, trig_cfg);
 344
 345  /* Ack interrupt */
 346  ack_intr.trig = 1;
 347        REG_WR(timer, regi_timer0, rw_ack_intr, ack_intr);
 348
 349  fast_timer_running = 0;
 350  fast_timer_ints++;
 351
 352        fast_timer_function_type *f;
 353        unsigned long d;
 354
 355  t = fast_timer_list;
 356        while (t) {
 357                struct fasttime_t tv;
 358
 359    /* Has it really expired? */
 360    do_gettimeofday_fast(&tv);
 361                D1(printk(KERN_DEBUG
 362                        "t: %is %06ius\n", tv.tv_jiff, tv.tv_usec));
 363
 364                if (fasttime_cmp(&t->tv_expires, &tv) <= 0) {
 365      /* Yes it has expired */
 366#ifdef FAST_TIMER_LOG
 367      timer_expired_log[fast_timers_expired % NUM_TIMER_STATS] = *t;
 368#endif
 369      fast_timers_expired++;
 370
 371      /* Remove this timer before call, since it may reuse the timer */
 372      if (t->prev)
 373        t->prev->next = t->next;
 374      else
 375        fast_timer_list = t->next;
 376      if (t->next)
 377        t->next->prev = t->prev;
 378      t->prev = NULL;
 379      t->next = NULL;
 380
 381                        /* Save function callback data before enabling
 382                         * interrupts, since the timer may be removed and we
 383                         * don't know how it was allocated (e.g. ->function
 384                         * and ->data may become overwritten after deletion
 385                         * if the timer was stack-allocated).
 386                         */
 387                        f = t->function;
 388                        d = t->data;
 389
 390                        if (f != NULL) {
 391                                /* Run the callback function with interrupts
 392                                 * enabled. */
 393                                local_irq_restore(flags);
 394                                f(d);
 395                                local_irq_save(flags);
 396                        } else
 397        DEBUG_LOG("!trimertrig %i function==NULL!\n", fast_timer_ints);
 398                } else {
 399      /* Timer is to early, let's set it again using the normal routines */
 400      D1(printk(".\n"));
 401    }
 402
 403                t = fast_timer_list;
 404                if (t != NULL) {
 405      /* Start next timer.. */
 406                        long us = 0;
 407                        struct fasttime_t tv;
 408
 409      do_gettimeofday_fast(&tv);
 410
 411                        /* time_after_eq takes care of wrapping */
 412                        if (time_after_eq(t->tv_expires.tv_jiff, tv.tv_jiff))
 413                                us = ((t->tv_expires.tv_jiff - tv.tv_jiff) *
 414                                        1000000 / HZ + t->tv_expires.tv_usec -
 415                                        tv.tv_usec);
 416
 417                        if (us > 0) {
 418                                if (!fast_timer_running) {
 419#ifdef FAST_TIMER_LOG
 420          timer_started_log[fast_timers_started % NUM_TIMER_STATS] = *t;
 421#endif
 422          start_timer_trig(us);
 423        }
 424        break;
 425                        } else {
 426        /* Timer already expired, let's handle it better late than never.
 427         * The normal loop handles it
 428         */
 429        D1(printk("e! %d\n", us));
 430      }
 431    }
 432  }
 433
 434        local_irq_restore(flags);
 435
 436        if (!t)
 437    D1(printk("ttrig stop!\n"));
 438}
 439
 440static void wake_up_func(unsigned long data)
 441{
 442  wait_queue_head_t  *sleep_wait_p = (wait_queue_head_t*)data;
 443  wake_up(sleep_wait_p);
 444}
 445
 446
 447/* Useful API */
 448
 449void schedule_usleep(unsigned long us)
 450{
 451  struct fast_timer t;
 452  wait_queue_head_t sleep_wait;
 453  init_waitqueue_head(&sleep_wait);
 454
 455  D1(printk("schedule_usleep(%d)\n", us));
 456  start_one_shot_timer(&t, wake_up_func, (unsigned long)&sleep_wait, us,
 457                       "usleep");
 458        /* Uninterruptible sleep on the fast timer. (The condition is
 459         * somewhat redundant since the timer is what wakes us up.) */
 460        wait_event(sleep_wait, !fast_timer_pending(&t));
 461
 462  D1(printk("done schedule_usleep(%d)\n", us));
 463}
 464
 465#ifdef CONFIG_PROC_FS
 466static int proc_fasttimer_read(char *buf, char **start, off_t offset, int len
 467                       ,int *eof, void *data_unused);
 468static struct proc_dir_entry *fasttimer_proc_entry;
 469#endif /* CONFIG_PROC_FS */
 470
 471#ifdef CONFIG_PROC_FS
 472
 473/* This value is very much based on testing */
 474#define BIG_BUF_SIZE (500 + NUM_TIMER_STATS * 300)
 475
 476static int proc_fasttimer_read(char *buf, char **start, off_t offset, int len
 477                       ,int *eof, void *data_unused)
 478{
 479  unsigned long flags;
 480  int i = 0;
 481  int num_to_show;
 482        struct fasttime_t tv;
 483  struct fast_timer *t, *nextt;
 484  static char *bigbuf = NULL;
 485  static unsigned long used;
 486
 487        if (!bigbuf) {
 488                bigbuf = vmalloc(BIG_BUF_SIZE);
 489                if (!bigbuf) {
 490                        used = 0;
 491                        if (buf)
 492                                buf[0] = '\0';
 493                        return 0;
 494                }
 495        }
 496
 497        if (!offset || !used) {
 498    do_gettimeofday_fast(&tv);
 499
 500    used = 0;
 501    used += sprintf(bigbuf + used, "Fast timers added:     %i\n",
 502                    fast_timers_added);
 503    used += sprintf(bigbuf + used, "Fast timers started:   %i\n",
 504                    fast_timers_started);
 505    used += sprintf(bigbuf + used, "Fast timer interrupts: %i\n",
 506                    fast_timer_ints);
 507    used += sprintf(bigbuf + used, "Fast timers expired:   %i\n",
 508                    fast_timers_expired);
 509    used += sprintf(bigbuf + used, "Fast timers deleted:   %i\n",
 510                    fast_timers_deleted);
 511    used += sprintf(bigbuf + used, "Fast timer running:    %s\n",
 512                    fast_timer_running ? "yes" : "no");
 513    used += sprintf(bigbuf + used, "Current time:          %lu.%06lu\n",
 514                        (unsigned long)tv.tv_jiff,
 515                    (unsigned long)tv.tv_usec);
 516#ifdef FAST_TIMER_SANITY_CHECKS
 517    used += sprintf(bigbuf + used, "Sanity failed:         %i\n",
 518                    sanity_failed);
 519#endif
 520    used += sprintf(bigbuf + used, "\n");
 521
 522#ifdef DEBUG_LOG_INCLUDED
 523    {
 524      int end_i = debug_log_cnt;
 525      i = 0;
 526
 527                        if (debug_log_cnt_wrapped)
 528        i = debug_log_cnt;
 529
 530      while ((i != end_i || (debug_log_cnt_wrapped && !used)) &&
 531             used+100 < BIG_BUF_SIZE)
 532      {
 533        used += sprintf(bigbuf + used, debug_log_string[i],
 534                        debug_log_value[i]);
 535        i = (i+1) % DEBUG_LOG_MAX;
 536      }
 537    }
 538    used += sprintf(bigbuf + used, "\n");
 539#endif
 540
 541    num_to_show = (fast_timers_started < NUM_TIMER_STATS ? fast_timers_started:
 542                   NUM_TIMER_STATS);
 543    used += sprintf(bigbuf + used, "Timers started: %i\n", fast_timers_started);
 544    for (i = 0; i < num_to_show && (used+100 < BIG_BUF_SIZE) ; i++)
 545    {
 546      int cur = (fast_timers_started - i - 1) % NUM_TIMER_STATS;
 547
 548#if 1 //ndef FAST_TIMER_LOG
 549      used += sprintf(bigbuf + used, "div: %i delay: %i"
 550                      "\n",
 551                      timer_div_settings[cur],
 552                      timer_delay_settings[cur]
 553                      );
 554#endif
 555#ifdef FAST_TIMER_LOG
 556      t = &timer_started_log[cur];
 557      used += sprintf(bigbuf + used, "%-14s s: %6lu.%06lu e: %6lu.%06lu "
 558                      "d: %6li us data: 0x%08lX"
 559                      "\n",
 560                      t->name,
 561                                (unsigned long)t->tv_set.tv_jiff,
 562                      (unsigned long)t->tv_set.tv_usec,
 563                                (unsigned long)t->tv_expires.tv_jiff,
 564                      (unsigned long)t->tv_expires.tv_usec,
 565                      t->delay_us,
 566                      t->data
 567                      );
 568#endif
 569    }
 570    used += sprintf(bigbuf + used, "\n");
 571
 572#ifdef FAST_TIMER_LOG
 573    num_to_show = (fast_timers_added < NUM_TIMER_STATS ? fast_timers_added:
 574                   NUM_TIMER_STATS);
 575    used += sprintf(bigbuf + used, "Timers added: %i\n", fast_timers_added);
 576    for (i = 0; i < num_to_show && (used+100 < BIG_BUF_SIZE); i++)
 577    {
 578      t = &timer_added_log[(fast_timers_added - i - 1) % NUM_TIMER_STATS];
 579      used += sprintf(bigbuf + used, "%-14s s: %6lu.%06lu e: %6lu.%06lu "
 580                      "d: %6li us data: 0x%08lX"
 581                      "\n",
 582                      t->name,
 583                                (unsigned long)t->tv_set.tv_jiff,
 584                      (unsigned long)t->tv_set.tv_usec,
 585                                (unsigned long)t->tv_expires.tv_jiff,
 586                      (unsigned long)t->tv_expires.tv_usec,
 587                      t->delay_us,
 588                      t->data
 589                      );
 590    }
 591    used += sprintf(bigbuf + used, "\n");
 592
 593    num_to_show = (fast_timers_expired < NUM_TIMER_STATS ? fast_timers_expired:
 594                   NUM_TIMER_STATS);
 595    used += sprintf(bigbuf + used, "Timers expired: %i\n", fast_timers_expired);
 596    for (i = 0; i < num_to_show && (used+100 < BIG_BUF_SIZE); i++)
 597    {
 598      t = &timer_expired_log[(fast_timers_expired - i - 1) % NUM_TIMER_STATS];
 599      used += sprintf(bigbuf + used, "%-14s s: %6lu.%06lu e: %6lu.%06lu "
 600                      "d: %6li us data: 0x%08lX"
 601                      "\n",
 602                      t->name,
 603                                (unsigned long)t->tv_set.tv_jiff,
 604                      (unsigned long)t->tv_set.tv_usec,
 605                                (unsigned long)t->tv_expires.tv_jiff,
 606                      (unsigned long)t->tv_expires.tv_usec,
 607                      t->delay_us,
 608                      t->data
 609                      );
 610    }
 611    used += sprintf(bigbuf + used, "\n");
 612#endif
 613
 614    used += sprintf(bigbuf + used, "Active timers:\n");
 615    local_irq_save(flags);
 616    t = fast_timer_list;
 617    while (t != NULL && (used+100 < BIG_BUF_SIZE))
 618    {
 619      nextt = t->next;
 620      local_irq_restore(flags);
 621      used += sprintf(bigbuf + used, "%-14s s: %6lu.%06lu e: %6lu.%06lu "
 622                        "d: %6li us data: 0x%08lX"
 623/*                      " func: 0x%08lX" */
 624                        "\n",
 625                        t->name,
 626                        (unsigned long)t->tv_set.tv_jiff,
 627                        (unsigned long)t->tv_set.tv_usec,
 628                        (unsigned long)t->tv_expires.tv_jiff,
 629                        (unsigned long)t->tv_expires.tv_usec,
 630                      t->delay_us,
 631                      t->data
 632/*                      , t->function */
 633                      );
 634                        local_irq_save(flags);
 635      if (t->next != nextt)
 636      {
 637        printk("timer removed!\n");
 638      }
 639      t = nextt;
 640    }
 641    local_irq_restore(flags);
 642  }
 643
 644  if (used - offset < len)
 645  {
 646    len = used - offset;
 647  }
 648
 649  memcpy(buf, bigbuf + offset, len);
 650  *start = buf;
 651  *eof = 1;
 652
 653  return len;
 654}
 655#endif /* PROC_FS */
 656
 657#ifdef FAST_TIMER_TEST
 658static volatile unsigned long i = 0;
 659static volatile int num_test_timeout = 0;
 660static struct fast_timer tr[10];
 661static int exp_num[10];
 662
 663static struct fasttime_t tv_exp[100];
 664
 665static void test_timeout(unsigned long data)
 666{
 667  do_gettimeofday_fast(&tv_exp[data]);
 668  exp_num[data] = num_test_timeout;
 669
 670  num_test_timeout++;
 671}
 672
 673static void test_timeout1(unsigned long data)
 674{
 675  do_gettimeofday_fast(&tv_exp[data]);
 676  exp_num[data] = num_test_timeout;
 677  if (data < 7)
 678  {
 679    start_one_shot_timer(&tr[i], test_timeout1, i, 1000, "timeout1");
 680    i++;
 681  }
 682  num_test_timeout++;
 683}
 684
 685DP(
 686static char buf0[2000];
 687static char buf1[2000];
 688static char buf2[2000];
 689static char buf3[2000];
 690static char buf4[2000];
 691);
 692
 693static char buf5[6000];
 694static int j_u[1000];
 695
 696static void fast_timer_test(void)
 697{
 698  int prev_num;
 699  int j;
 700
 701        struct fasttime_t tv, tv0, tv1, tv2;
 702
 703  printk("fast_timer_test() start\n");
 704  do_gettimeofday_fast(&tv);
 705
 706  for (j = 0; j < 1000; j++)
 707  {
 708    j_u[j] = GET_JIFFIES_USEC();
 709  }
 710  for (j = 0; j < 100; j++)
 711  {
 712    do_gettimeofday_fast(&tv_exp[j]);
 713  }
 714  printk(KERN_DEBUG "fast_timer_test() %is %06i\n", tv.tv_jiff, tv.tv_usec);
 715
 716  for (j = 0; j < 1000; j++)
 717  {
 718    printk(KERN_DEBUG "%i %i %i %i %i\n",
 719      j_u[j], j_u[j+1], j_u[j+2], j_u[j+3], j_u[j+4]);
 720    j += 4;
 721  }
 722  for (j = 0; j < 100; j++)
 723  {
 724    printk(KERN_DEBUG "%i.%i %i.%i %i.%i %i.%i %i.%i\n",
 725                        tv_exp[j].tv_jiff, tv_exp[j].tv_usec,
 726                        tv_exp[j+1].tv_jiff, tv_exp[j+1].tv_usec,
 727                        tv_exp[j+2].tv_jiff, tv_exp[j+2].tv_usec,
 728                        tv_exp[j+3].tv_jiff, tv_exp[j+3].tv_usec,
 729                        tv_exp[j+4].tv_jiff, tv_exp[j+4].tv_usec);
 730    j += 4;
 731  }
 732  do_gettimeofday_fast(&tv0);
 733  start_one_shot_timer(&tr[i], test_timeout, i, 50000, "test0");
 734  DP(proc_fasttimer_read(buf0, NULL, 0, 0, 0));
 735  i++;
 736  start_one_shot_timer(&tr[i], test_timeout, i, 70000, "test1");
 737  DP(proc_fasttimer_read(buf1, NULL, 0, 0, 0));
 738  i++;
 739  start_one_shot_timer(&tr[i], test_timeout, i, 40000, "test2");
 740  DP(proc_fasttimer_read(buf2, NULL, 0, 0, 0));
 741  i++;
 742  start_one_shot_timer(&tr[i], test_timeout, i, 60000, "test3");
 743  DP(proc_fasttimer_read(buf3, NULL, 0, 0, 0));
 744  i++;
 745  start_one_shot_timer(&tr[i], test_timeout1, i, 55000, "test4xx");
 746  DP(proc_fasttimer_read(buf4, NULL, 0, 0, 0));
 747  i++;
 748  do_gettimeofday_fast(&tv1);
 749
 750  proc_fasttimer_read(buf5, NULL, 0, 0, 0);
 751
 752  prev_num = num_test_timeout;
 753  while (num_test_timeout < i)
 754  {
 755    if (num_test_timeout != prev_num)
 756      prev_num = num_test_timeout;
 757  }
 758  do_gettimeofday_fast(&tv2);
 759        printk(KERN_INFO "Timers started    %is %06i\n",
 760                tv0.tv_jiff, tv0.tv_usec);
 761        printk(KERN_INFO "Timers started at %is %06i\n",
 762                tv1.tv_jiff, tv1.tv_usec);
 763        printk(KERN_INFO "Timers done       %is %06i\n",
 764                tv2.tv_jiff, tv2.tv_usec);
 765  DP(printk("buf0:\n");
 766     printk(buf0);
 767     printk("buf1:\n");
 768     printk(buf1);
 769     printk("buf2:\n");
 770     printk(buf2);
 771     printk("buf3:\n");
 772     printk(buf3);
 773     printk("buf4:\n");
 774     printk(buf4);
 775  );
 776  printk("buf5:\n");
 777  printk(buf5);
 778
 779  printk("timers set:\n");
 780  for(j = 0; j<i; j++)
 781  {
 782    struct fast_timer *t = &tr[j];
 783    printk("%-10s set: %6is %06ius exp: %6is %06ius "
 784           "data: 0x%08X func: 0x%08X\n",
 785           t->name,
 786                        t->tv_set.tv_jiff,
 787           t->tv_set.tv_usec,
 788                        t->tv_expires.tv_jiff,
 789           t->tv_expires.tv_usec,
 790           t->data,
 791           t->function
 792           );
 793
 794    printk("           del: %6ius     did exp: %6is %06ius as #%i error: %6li\n",
 795           t->delay_us,
 796                        tv_exp[j].tv_jiff,
 797           tv_exp[j].tv_usec,
 798           exp_num[j],
 799                        (tv_exp[j].tv_jiff - t->tv_expires.tv_jiff) *
 800                                1000000 + tv_exp[j].tv_usec -
 801                                t->tv_expires.tv_usec);
 802  }
 803  proc_fasttimer_read(buf5, NULL, 0, 0, 0);
 804  printk("buf5 after all done:\n");
 805  printk(buf5);
 806  printk("fast_timer_test() done\n");
 807}
 808#endif
 809
 810
 811int fast_timer_init(void)
 812{
 813  /* For some reason, request_irq() hangs when called froom time_init() */
 814  if (!fast_timer_is_init)
 815  {
 816    printk("fast_timer_init()\n");
 817
 818#ifdef CONFIG_PROC_FS
 819    fasttimer_proc_entry = create_proc_entry("fasttimer", 0, 0);
 820    if (fasttimer_proc_entry)
 821      fasttimer_proc_entry->read_proc = proc_fasttimer_read;
 822#endif /* PROC_FS */
 823                if (request_irq(TIMER0_INTR_VECT, timer_trig_interrupt,
 824                                IRQF_SHARED | IRQF_DISABLED,
 825                                "fast timer int", &fast_timer_list))
 826                        printk(KERN_ERR "err: fasttimer irq\n");
 827    fast_timer_is_init = 1;
 828#ifdef FAST_TIMER_TEST
 829    printk("do test\n");
 830    fast_timer_test();
 831#endif
 832  }
 833        return 0;
 834}
 835__initcall(fast_timer_init);
 836