time.c

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00001 /*
00002  * Copyright (C) 2006 Ondrej Palkovsky
00003  * All rights reserved.
00004  *
00005  * Redistribution and use in source and binary forms, with or without
00006  * modification, are permitted provided that the following conditions
00007  * are met:
00008  *
00009  * - Redistributions of source code must retain the above copyright
00010  *   notice, this list of conditions and the following disclaimer.
00011  * - Redistributions in binary form must reproduce the above copyright
00012  *   notice, this list of conditions and the following disclaimer in the
00013  *   documentation and/or other materials provided with the distribution.
00014  * - The name of the author may not be used to endorse or promote products
00015  *   derived from this software without specific prior written permission.
00016  *
00017  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
00018  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
00019  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
00020  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
00021  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
00022  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
00023  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
00024  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
00025  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
00026  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00027  */
00028 
00035 #include <sys/time.h>
00036 #include <unistd.h>
00037 #include <ipc/ipc.h>
00038 #include <stdio.h>
00039 #include <arch/barrier.h>
00040 #include <unistd.h>
00041 #include <atomic.h>
00042 #include <futex.h>
00043 #include <ipc/services.h>
00044 
00045 #include <sysinfo.h>
00046 #include <as.h>
00047 #include <ddi.h>
00048 
00049 /* Pointers to public variables with time */
00050 struct {
00051         volatile sysarg_t seconds1;
00052         volatile sysarg_t useconds;
00053         volatile sysarg_t seconds2;
00054 } *ktime = NULL;
00055 
00056 
00066 int gettimeofday(struct timeval *tv, struct timezone *tz)
00067 {
00068         void *mapping;
00069         sysarg_t s1, s2;
00070         sysarg_t rights;
00071         int res;
00072 
00073         if (!ktime) {
00074                 mapping = as_get_mappable_page(PAGE_SIZE);
00075                 /* Get the mapping of kernel clock */
00076                 res = ipc_call_sync_3(PHONE_NS, IPC_M_AS_AREA_RECV, (sysarg_t) mapping, PAGE_SIZE, SERVICE_MEM_REALTIME, NULL, &rights, NULL);
00077                 if (res) {
00078                         printf("Failed to initialize timeofday memarea\n");
00079                         _exit(1);
00080                 }
00081                 if (! (rights & AS_AREA_READ)) {
00082                         printf("Received bad rights on time area: %X\n",
00083                                rights);
00084                         as_area_destroy(mapping);
00085                         _exit(1);
00086                 }
00087                 ktime = mapping;
00088         }
00089         if (tz) {
00090                 tz->tz_minuteswest = 0;
00091                 tz->tz_dsttime = DST_NONE;
00092         }
00093 
00094         s2 = ktime->seconds2;
00095         read_barrier();
00096         tv->tv_usec = ktime->useconds;
00097         read_barrier();
00098         s1 = ktime->seconds1;
00099         if (s1 != s2) {
00100                 tv->tv_usec = 0;
00101                 tv->tv_sec = s1 > s2 ? s1 : s2;
00102         } else
00103                 tv->tv_sec = s1;
00104 
00105         return 0;
00106 }
00107 
00109 void usleep(unsigned long usec)
00110 {
00111         atomic_t futex = FUTEX_INITIALIZER;
00112 
00113         futex_initialize(&futex,0);
00114         futex_down_timeout(&futex, usec, 0);
00115 }
00116 
00117 

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