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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. /* Pointers to public variables with time */
  51. struct {
  52.     volatile sysarg_t seconds1;
  53.     volatile sysarg_t useconds;
  54.     volatile sysarg_t seconds2;
  55. } *ktime = NULL;
  56.  
  57.  
  58. /** POSIX gettimeofday
  59.  *
  60.  * The time variables are memory mapped(RO) from kernel, which updates
  61.  * them periodically. As it is impossible to read 2 values atomically, we
  62.  * use a trick: First read a seconds, then read microseconds, then
  63.  * read seconds again. If a second elapsed in the meantime, set it to zero.
  64.  * This provides assurance, that at least the
  65.  * sequence of subsequent gettimeofday calls is ordered.
  66.  */
  67. int gettimeofday(struct timeval *tv, struct timezone *tz)
  68. {
  69.     void *mapping;
  70.     sysarg_t s1, s2;
  71.     sysarg_t rights;
  72.     int res;
  73.  
  74.     if (!ktime) {
  75.         mapping = as_get_mappable_page(PAGE_SIZE);
  76.         /* Get the mapping of kernel clock */
  77.         res = ipc_call_sync_3(PHONE_NS, IPC_M_AS_AREA_RECV,
  78.             (sysarg_t) mapping, PAGE_SIZE, SERVICE_MEM_REALTIME, NULL,
  79.             &rights, NULL);
  80.         if (res) {
  81.             printf("Failed to initialize timeofday memarea\n");
  82.             _exit(1);
  83.         }
  84.         if (! (rights & AS_AREA_READ)) {
  85.             printf("Received bad rights on time area: %X\n",
  86.                    rights);
  87.             as_area_destroy(mapping);
  88.             _exit(1);
  89.         }
  90.         ktime = mapping;
  91.     }
  92.     if (tz) {
  93.         tz->tz_minuteswest = 0;
  94.         tz->tz_dsttime = DST_NONE;
  95.     }
  96.  
  97.     s2 = ktime->seconds2;
  98.     read_barrier();
  99.     tv->tv_usec = ktime->useconds;
  100.     read_barrier();
  101.     s1 = ktime->seconds1;
  102.     if (s1 != s2) {
  103.         tv->tv_usec = 0;
  104.         tv->tv_sec = s1 > s2 ? s1 : s2;
  105.     } else
  106.         tv->tv_sec = s1;
  107.  
  108.     return 0;
  109. }
  110.  
  111. /** Wait unconditionally for specified number of microseconds */
  112. void usleep(unsigned long usec)
  113. {
  114.     atomic_t futex = FUTEX_INITIALIZER;
  115.  
  116.     futex_initialize(&futex, 0);
  117.     futex_down_timeout(&futex, usec, 0);
  118. }
  119.  
  120. /** Wait unconditionally for specified number of seconds */
  121. unsigned int sleep(unsigned int seconds)
  122. {
  123.     atomic_t futex = FUTEX_INITIALIZER;
  124.  
  125.     futex_initialize(&futex, 0);
  126.    
  127.     /* Sleep in 1000 second steps to support
  128.        full argument range */
  129.     while (seconds > 0) {
  130.         unsigned int period = (seconds > 1000) ? 1000 : seconds;
  131.    
  132.         futex_down_timeout(&futex, period * 1000000, 0);
  133.         seconds -= period;
  134.     }
  135. }
  136.  
  137. /** @}
  138.  */
  139.