The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/dev/ic/mm58167.c

Version: -  FREEBSD  -  FREEBSD-13-STABLE  -  FREEBSD-13-0  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  l41  -  OPENBSD  -  linux-2.6  -  MK84  -  PLAN9  -  xnu-8792 
SearchContext: -  none  -  3  -  10 

    1 /*      $NetBSD: mm58167.c,v 1.5 2005/02/27 00:27:02 perry Exp $        */
    2 
    3 /*
    4  * Copyright (c) 2001 The NetBSD Foundation, Inc.
    5  * All rights reserved.
    6  *
    7  * This code is derived from software contributed to The NetBSD Foundation
    8  * by Matthew Fredette.
    9  *
   10  * Redistribution and use in source and binary forms, with or without
   11  * modification, are permitted provided that the following conditions
   12  * are met:
   13  * 1. Redistributions of source code must retain the above copyright
   14  *    notice, this list of conditions and the following disclaimer.
   15  * 2. Redistributions in binary form must reproduce the above copyright
   16  *    notice, this list of conditions and the following disclaimer in the
   17  *    documentation and/or other materials provided with the distribution.
   18  * 3. All advertising materials mentioning features or use of this software
   19  *    must display the following acknowledgement:
   20  *        This product includes software developed by the NetBSD
   21  *        Foundation, Inc. and its contributors.
   22  * 4. Neither the name of The NetBSD Foundation nor the names of its
   23  *    contributors may be used to endorse or promote products derived
   24  *    from this software without specific prior written permission.
   25  *
   26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
   27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
   28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
   30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   36  * POSSIBILITY OF SUCH DAMAGE.
   37  */
   38 
   39 /*
   40  * National Semiconductor MM58167 time-of-day chip subroutines.
   41  */
   42 
   43 #include <sys/cdefs.h>
   44 __KERNEL_RCSID(0, "$NetBSD: mm58167.c,v 1.5 2005/02/27 00:27:02 perry Exp $");
   45 
   46 #include <sys/param.h>
   47 #include <sys/malloc.h>
   48 #include <sys/systm.h>
   49 #include <sys/errno.h>
   50 #include <sys/device.h>
   51 
   52 #include <machine/bus.h>
   53 #include <dev/clock_subr.h>
   54 #include <dev/ic/mm58167var.h>
   55 
   56 int mm58167_gettime(todr_chip_handle_t, struct timeval *);
   57 int mm58167_settime(todr_chip_handle_t, struct timeval *);
   58 int mm58167_getcal(todr_chip_handle_t, int *);
   59 int mm58167_setcal(todr_chip_handle_t, int);
   60 
   61 /*
   62  * To quote SunOS's todreg.h:
   63  * "This brain damaged chip insists on keeping the time in
   64  *  MM/DD HH:MM:SS format, even though it doesn't know about
   65  *  leap years and Feb. 29, thus making it nearly worthless."
   66  */
   67 #define mm58167_read(sc, r) bus_space_read_1(sc->mm58167_regt, sc->mm58167_regh, sc-> r)
   68 #define mm58167_write(sc, r, v) bus_space_write_1(sc->mm58167_regt, sc->mm58167_regh, sc-> r, v)
   69 
   70 todr_chip_handle_t
   71 mm58167_attach(sc)
   72         struct mm58167_softc *sc;
   73 {
   74         struct todr_chip_handle *handle;
   75 
   76         printf(": mm58167");
   77 
   78         handle = &sc->_mm58167_todr_handle;
   79         memset(handle, 0, sizeof(handle));
   80         handle->cookie = sc;
   81         handle->todr_gettime = mm58167_gettime;
   82         handle->todr_settime = mm58167_settime;
   83         handle->todr_getcal = mm58167_getcal;
   84         handle->todr_setcal = mm58167_setcal;
   85         return (handle);
   86 }
   87 
   88 /*
   89  * Set up the system's time, given a `reasonable' time value.
   90  */
   91 int
   92 mm58167_gettime(handle, tv)
   93         todr_chip_handle_t handle;
   94         struct timeval *tv;
   95 {
   96         struct mm58167_softc *sc = handle->cookie;
   97         struct clock_ymdhms dt_hardware;
   98         struct clock_ymdhms dt_reasonable;
   99         int s;
  100         u_int8_t byte_value;
  101         int leap_year, had_leap_day;
  102 
  103         /* First, read the date out of the chip. */
  104 
  105         /* No interrupts while we're in the chip. */
  106         s = splhigh();
  107 
  108         /* Reset the status bit: */
  109         byte_value = mm58167_read(sc, mm58167_status);
  110 
  111         /*
  112          * Read the date values until we get a coherent read (one
  113          * where the status stays zero, indicating no increment was
  114          * rippling through while we were reading).
  115          */
  116         do {
  117 #define _MM58167_GET(dt_f, mm_f) byte_value = mm58167_read(sc, mm_f); dt_hardware.dt_f = FROMBCD(byte_value)
  118                 _MM58167_GET(dt_mon, mm58167_mon);
  119                 _MM58167_GET(dt_day, mm58167_day);
  120                 _MM58167_GET(dt_hour, mm58167_hour);
  121                 _MM58167_GET(dt_min, mm58167_min);
  122                 _MM58167_GET(dt_sec, mm58167_sec);
  123 #undef _MM58167_GET
  124         } while ((mm58167_read(sc, mm58167_status) & 1) == 0);
  125 
  126         splx(s);
  127 
  128         /* Convert the reasonable time into a date: */
  129         clock_secs_to_ymdhms(tv->tv_sec, &dt_reasonable);
  130 
  131         /*
  132          * We need to fake a hardware year.  if the hardware MM/DD
  133          * HH:MM:SS date is less than the reasonable MM/DD
  134          * HH:MM:SS, call it the reasonable year plus one, else call
  135          * it the reasonable year.
  136          */
  137         if (dt_hardware.dt_mon < dt_reasonable.dt_mon ||
  138             (dt_hardware.dt_mon == dt_reasonable.dt_mon &&
  139                 (dt_hardware.dt_day < dt_reasonable.dt_day ||
  140                     (dt_hardware.dt_day == dt_reasonable.dt_day &&
  141                         (dt_hardware.dt_hour < dt_reasonable.dt_hour ||
  142                             (dt_hardware.dt_hour == dt_reasonable.dt_hour &&
  143                                 (dt_hardware.dt_min < dt_reasonable.dt_min ||
  144                                     (dt_hardware.dt_min == dt_reasonable.dt_min &&
  145                                         (dt_hardware.dt_sec < dt_reasonable.dt_sec))))))))) {
  146           dt_hardware.dt_year = dt_reasonable.dt_year + 1;
  147         } else {
  148           dt_hardware.dt_year = dt_reasonable.dt_year;
  149         }
  150 
  151         /* convert the hardware date into a time: */
  152         tv->tv_sec = clock_ymdhms_to_secs(&dt_hardware);
  153         tv->tv_usec = 0;
  154 
  155         /*
  156          * Make a reasonable effort to see if a leap day has passed
  157          * that we need to account for.  This does the right thing
  158          * only when the system was shut down before a leap day, and
  159          * it is now after that leap day.  It doesn't do the right
  160          * thing when a leap day happened while the machine was last
  161          * up.  When that happens, the hardware clock becomes
  162          * instantly wrong forever, until it gets fixed for some
  163          * reason.  Use NTP to deal.
  164          */
  165 
  166         /*
  167          * This may have happened if the hardware says we're into
  168          * March in the following year.  Check that following year for
  169          * a leap day.
  170          */
  171         if (dt_hardware.dt_year > dt_reasonable.dt_year &&
  172             dt_hardware.dt_mon >= 3) {
  173           leap_year = dt_hardware.dt_year;
  174         }
  175 
  176         /*
  177          * This may have happened if the hardware says we're in the
  178          * following year, and the system was shut down before March
  179          * the previous year.  check that previous year for a leap
  180          * day.
  181          */
  182         else if (dt_hardware.dt_year > dt_reasonable.dt_year &&
  183                  dt_reasonable.dt_mon < 3) {
  184           leap_year = dt_reasonable.dt_year;
  185         }
  186 
  187         /*
  188          * This may have happened if the hardware says we're in the
  189          * same year, but we weren't to March before, and we're in or
  190          * past March now.  Check this year for a leap day.
  191          */
  192         else if (dt_hardware.dt_year == dt_reasonable.dt_year
  193                  && dt_reasonable.dt_mon < 3
  194                  && dt_hardware.dt_mon >= 3) {
  195           leap_year = dt_reasonable.dt_year;
  196         }
  197 
  198         /*
  199          * Otherwise, no leap year to check.
  200          */
  201         else {
  202           leap_year = 0;
  203         }
  204 
  205         /* Do the real leap day check. */
  206         had_leap_day = 0;
  207         if (leap_year > 0) {
  208                 if ((leap_year & 3) == 0) {
  209                         had_leap_day = 1;
  210                         if ((leap_year % 100) == 0) {
  211                                 had_leap_day = 0;
  212                                 if ((leap_year % 400) == 0)
  213                                         had_leap_day = 1;
  214                         }
  215                 }
  216         }
  217 
  218         /*
  219          * If we had a leap day, adjust the value we will return, and
  220          * also update the hardware clock.
  221          */
  222         /*
  223          * XXX - Since this update just writes back a corrected
  224          * version of what we read out above, we lose whatever
  225          * amount of time the clock has advanced since that read.
  226          * Use NTP to deal.
  227          */
  228         if (had_leap_day) {
  229           tv->tv_sec += SECDAY;
  230           todr_settime(handle, tv);
  231         }
  232 
  233         return (0);
  234 }
  235 
  236 int
  237 mm58167_settime(handle, tv)
  238         todr_chip_handle_t handle;
  239         struct timeval *tv;
  240 {
  241         struct mm58167_softc *sc = handle->cookie;
  242         struct clock_ymdhms dt_hardware;
  243         int s;
  244         u_int8_t byte_value;
  245 
  246         /* Convert the seconds into ymdhms. */
  247         clock_secs_to_ymdhms(tv->tv_sec, &dt_hardware);
  248 
  249         /* No interrupts while we're in the chip. */
  250         s = splhigh();
  251 
  252         /*
  253          * Issue a GO command to reset everything less significant
  254          * than the minutes to zero.
  255          */
  256         mm58167_write(sc, mm58167_go, 0xFF);
  257 
  258         /* Load everything. */
  259 #define _MM58167_PUT(dt_f, mm_f) byte_value = TOBCD(dt_hardware.dt_f); mm58167_write(sc, mm_f, byte_value)
  260         _MM58167_PUT(dt_mon, mm58167_mon);
  261         _MM58167_PUT(dt_day, mm58167_day);
  262         _MM58167_PUT(dt_hour, mm58167_hour);
  263         _MM58167_PUT(dt_min, mm58167_min);
  264         _MM58167_PUT(dt_sec, mm58167_sec);
  265 #undef _MM58167_PUT
  266 
  267         splx(s);
  268         return (0);
  269 }
  270 
  271 int
  272 mm58167_getcal(handle, vp)
  273         todr_chip_handle_t handle;
  274         int *vp;
  275 {
  276         return (EOPNOTSUPP);
  277 }
  278 
  279 int
  280 mm58167_setcal(handle, v)
  281         todr_chip_handle_t handle;
  282         int v;
  283 {
  284         return (EOPNOTSUPP);
  285 }

Cache object: 4e6b1810e6cb86adf4e6273c33b6123c


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.