arch/x86/kernel/platform/i86pc/io/hardclk.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 /*      Copyright (c) 1990, 1991 UNIX System Laboratories, Inc. */
  28 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989, 1990 AT&T   */
  29 /*        All Rights Reserved   */
  30
  31 #include <sys/param.h>
  32 #include <sys/time.h>
  33 #include <sys/systm.h>
  34 #include <sys/archsystm.h>
  35 #include <sys/lockstat.h>
  36
  37 #include <sys/clock.h>
  38 #include <sys/debug.h>
  39 #include <sys/smp_impldefs.h>
  40 #include <sys/rtc.h>
  41
  42 /*
  43  * This file contains all generic part of clock and timer handling.
  44  * Specifics are now in separate files and may be overridden by TOD
  45  * modules.
  46  */
  47
  48 char *tod_module_name;          /* Settable in /etc/system */
  49
  50 extern void tod_set_prev(timestruc_t);
  51
  52 /*
  53  * Write the specified time into the clock chip.
  54  * Must be called with tod_lock held.
  55  */
  56 void
  57 tod_set(timestruc_t ts)
  58 {
  59         ASSERT(MUTEX_HELD(&tod_lock));
  60
  61         tod_set_prev(ts);               /* for tod_validate() */
  62         TODOP_SET(tod_ops, ts);
  63         tod_status_set(TOD_SET_DONE);   /* TOD was modified */
  64 }
  65
  66 /*
  67  * Read the current time from the clock chip and convert to UNIX form.
  68  * Assumes that the year in the clock chip is valid.
  69  * Must be called with tod_lock held.
  70  */
  71 timestruc_t
  72 tod_get(void)
  73 {
  74         timestruc_t ts;
  75
  76         ASSERT(MUTEX_HELD(&tod_lock));
  77
  78         ts = TODOP_GET(tod_ops);
  79         ts.tv_sec = tod_validate(ts.tv_sec);
  80         return (ts);
  81 }
  82
  83 /*
  84  * The following wrappers have been added so that locking
  85  * can be exported to platform-independent clock routines
  86  * (ie adjtime(), clock_setttime()), via a functional interface.
  87  */
  88 int
  89 hr_clock_lock(void)
  90 {
  91         ushort_t s;
  92
  93         CLOCK_LOCK(&s);
  94         return (s);
  95 }
  96
  97 void
  98 hr_clock_unlock(int s)
  99 {
 100         CLOCK_UNLOCK(s);
 101 }
 102
 103 /*
 104  * Support routines for horrid GMT lag handling
 105  */
 106
 107 static time_t gmt_lag;          /* offset in seconds of gmt to local time */
 108
 109 void
 110 sgmtl(time_t arg)
 111 {
 112         gmt_lag = arg;
 113 }
 114
 115 time_t
 116 ggmtl(void)
 117 {
 118         return (gmt_lag);
 119 }
 120
 121 /* rtcsync() - set 'time', assuming RTC and GMT lag are correct */
 122
 123 void
 124 rtcsync(void)
 125 {
 126         timestruc_t ts;
 127
 128         mutex_enter(&tod_lock);
 129         ts = TODOP_GET(tod_ops);
 130         set_hrestime(&ts);
 131         mutex_exit(&tod_lock);
 132 }