root/kern/dev/generic/rtclock.c

DEFINITIONS

1. config_rtclock
2. gettime

   1 /*
   2  * Copyright (c) 2000, 2001, 2002, 2003, 2004, 2005, 2008, 2009
   3  *      The President and Fellows of Harvard College.
   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  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE UNIVERSITY AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE UNIVERSITY OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  30 /*
  31  * Machine-independent generic clock "device".
  32  *
  33  * Basically, all we do is remember something that can be used for
  34  * handling requests for the current time, and provide the gettime()
  35  * function to the rest of the kernel.
  36  *
  37  * The kernel config mechanism can be used to explicitly choose which
  38  * of the available clocks to use, if more than one is available.
  39  *
  40  * The system will panic if gettime() is called and there is no clock.
  41  */
  43 #include <types.h>
  44 #include <kern/errno.h>
  45 #include <lib.h>
  46 #include <clock.h>
  47 #include <generic/rtclock.h>
  48 #include "autoconf.h"
  50 static struct rtclock_softc *the_clock = NULL;
  52 int
  53 config_rtclock(struct rtclock_softc *rtc, int unit)
  54 {
  55         /* We use only the first clock device. */
  56         if (unit!=0) {
  57                 return ENODEV;
  58         }
KASSERT(the_clock==NULL);
the_clock = rtc;
  62         return 0;
  63 }
  65 void
gettime(time_t *secs, uint32_t *nsecs)
  67 {
KASSERT(the_clock!=NULL);
the_clock->rtc_gettime(the_clock->rtc_devdata, secs, nsecs);
  70 }