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  1. /*
  2.  * Copyright (c) 2006 Ondrej Palkovsky
  3.  * All rights reserved.
  4.  *
  5.  * Redistribution and use in source and binary forms, with or without
  6.  * modification, are permitted provided that the following conditions
  7.  * are met:
  8.  *
  9.  * - Redistributions of source code must retain the above copyright
  10.  *   notice, this list of conditions and the following disclaimer.
  11.  * - Redistributions in binary form must reproduce the above copyright
  12.  *   notice, this list of conditions and the following disclaimer in the
  13.  *   documentation and/or other materials provided with the distribution.
  14.  * - The name of the author may not be used to endorse or promote products
  15.  *   derived from this software without specific prior written permission.
  16.  *
  17.  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18.  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19.  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20.  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21.  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22.  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23.  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24.  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25.  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26.  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27.  */
  28.  
  29. /** @addtogroup libc
  30.  * @{
  31.  */
  32. /** @file
  33.  */
  34.  
  35. #include <sys/time.h>
  36. #include <unistd.h>
  37. #include <ipc/ipc.h>
  38. #include <stdio.h>
  39. #include <arch/barrier.h>
  40. #include <unistd.h>
  41. #include <atomic.h>
  42. #include <futex.h>
  43. #include <sysinfo.h>
  44. #include <ipc/services.h>
  45.  
  46. #include <sysinfo.h>
  47. #include <as.h>
  48. #include <ddi.h>
  49.  
  50. #include <time.h>
  51.  
  52. /* Pointers to public variables with time */
  53. struct {
  54.     volatile sysarg_t seconds1;
  55.     volatile sysarg_t useconds;
  56.     volatile sysarg_t seconds2;
  57. } *ktime = NULL;
  58.  
  59. /** Add microseconds to given timeval.
  60.  *
  61.  * @param tv        Destination timeval.
  62.  * @param usecs     Number of microseconds to add.
  63.  */
  64. void tv_add(struct timeval *tv, suseconds_t usecs)
  65. {
  66.     tv->tv_sec += usecs / 1000000;
  67.     tv->tv_usec += usecs % 1000000;
  68.     if (tv->tv_usec > 1000000) {
  69.         tv->tv_sec++;
  70.         tv->tv_usec -= 1000000;
  71.     }
  72. }
  73.  
  74. /** Subtract two timevals.
  75.  *
  76.  * @param tv1       First timeval.
  77.  * @param tv2       Second timeval.
  78.  *
  79.  * @return      Return difference between tv1 and tv2 (tv1 - tv2) in
  80.  *          microseconds.
  81.  */
  82. suseconds_t tv_sub(struct timeval *tv1, struct timeval *tv2)
  83. {
  84.     suseconds_t result;
  85.  
  86.     result = tv1->tv_usec - tv2->tv_usec;
  87.     result += (tv1->tv_sec - tv2->tv_sec) * 1000000;
  88.  
  89.     return result;
  90. }
  91.  
  92. /** Decide if one timeval is greater than the other.
  93.  *
  94.  * @param t1        First timeval.
  95.  * @param t2        Second timeval.
  96.  *
  97.  * @return      Return true tv1 is greater than tv2. Otherwise return
  98.  *          false.
  99.  */
  100. int tv_gt(struct timeval *tv1, struct timeval *tv2)
  101. {
  102.     if (tv1->tv_sec > tv2->tv_sec)
  103.         return 1;
  104.     if (tv1->tv_sec == tv2->tv_sec && tv1->tv_usec > tv2->tv_usec)
  105.         return 1;
  106.     return 0;
  107. }
  108.  
  109. /** Decide if one timeval is greater than or equal to the other.
  110.  *
  111.  * @param tv1       First timeval.
  112.  * @param tv2       Second timeval.
  113.  *
  114.  * @return      Return true if tv1 is greater than or equal to tv2.
  115.  *          Otherwise return false.
  116.  */
  117. int tv_gteq(struct timeval *tv1, struct timeval *tv2)
  118. {
  119.     if (tv1->tv_sec > tv2->tv_sec)
  120.         return 1;
  121.     if (tv1->tv_sec == tv2->tv_sec && tv1->tv_usec >= tv2->tv_usec)
  122.         return 1;
  123.     return 0;
  124. }
  125.  
  126.  
  127. /** POSIX gettimeofday
  128.  *
  129.  * The time variables are memory mapped(RO) from kernel, which updates
  130.  * them periodically. As it is impossible to read 2 values atomically, we
  131.  * use a trick: First read a seconds, then read microseconds, then
  132.  * read seconds again. If a second elapsed in the meantime, set it to zero.
  133.  * This provides assurance, that at least the
  134.  * sequence of subsequent gettimeofday calls is ordered.
  135.  */
  136. int gettimeofday(struct timeval *tv, struct timezone *tz)
  137. {
  138.     void *mapping;
  139.     sysarg_t s1, s2;
  140.     int rights;
  141.     int res;
  142.  
  143.     if (!ktime) {
  144.         mapping = as_get_mappable_page(PAGE_SIZE);
  145.         /* Get the mapping of kernel clock */
  146.         res = ipc_share_in_start_1_1(PHONE_NS, mapping, PAGE_SIZE,
  147.             SERVICE_MEM_REALTIME, &rights);
  148.         if (res) {
  149.             printf("Failed to initialize timeofday memarea\n");
  150.             _exit(1);
  151.         }
  152.         if (!(rights & AS_AREA_READ)) {
  153.             printf("Received bad rights on time area: %X\n",
  154.                 rights);
  155.             as_area_destroy(mapping);
  156.             _exit(1);
  157.         }
  158.         ktime = mapping;
  159.     }
  160.     if (tz) {
  161.         tz->tz_minuteswest = 0;
  162.         tz->tz_dsttime = DST_NONE;
  163.     }
  164.  
  165.     s2 = ktime->seconds2;
  166.     read_barrier();
  167.     tv->tv_usec = ktime->useconds;
  168.     read_barrier();
  169.     s1 = ktime->seconds1;
  170.     if (s1 != s2) {
  171.         tv->tv_usec = 0;
  172.         tv->tv_sec = s1 > s2 ? s1 : s2;
  173.     } else
  174.         tv->tv_sec = s1;
  175.  
  176.     return 0;
  177. }
  178.  
  179. time_t time(time_t *tloc)
  180. {
  181.     struct timeval tv;
  182.  
  183.     if (gettimeofday(&tv, NULL))
  184.         return (time_t) -1;
  185.     if (tloc)
  186.         *tloc = tv.tv_sec;
  187.     return tv.tv_sec;
  188. }
  189.  
  190. /** Wait unconditionally for specified number of microseconds */
  191. int usleep(unsigned long usec)
  192. {
  193.     atomic_t futex = FUTEX_INITIALIZER;
  194.  
  195.     futex_initialize(&futex, 0);
  196.     futex_down_timeout(&futex, usec, 0);
  197.     return 0;
  198. }
  199.  
  200. /** Wait unconditionally for specified number of seconds */
  201. unsigned int sleep(unsigned int seconds)
  202. {
  203.     atomic_t futex = FUTEX_INITIALIZER;
  204.  
  205.     futex_initialize(&futex, 0);
  206.    
  207.     /* Sleep in 1000 second steps to support
  208.        full argument range */
  209.     while (seconds > 0) {
  210.         unsigned int period = (seconds > 1000) ? 1000 : seconds;
  211.    
  212.         futex_down_timeout(&futex, period * 1000000, 0);
  213.         seconds -= period;
  214.     }
  215.     return 0;
  216. }
  217.  
  218. /** @}
  219.  */
  220.