libgloss/moxie/qemu-time.c

   1 /* qemu-time.c -- stubs so clock can be linked in.
   2  *
   3  * Copyright (c) 2008 Anthony Green
   4  *
   5  * The authors hereby grant permission to use, copy, modify, distribute,
   6  * and license this software and its documentation for any purpose, provided
   7  * that existing copyright notices are retained in all copies and that this
   8  * notice is included verbatim in any distributions. No written agreement,
   9  * license, or royalty fee is required for any of the authorized uses.
  10  * Modifications to this software may be copyrighted by their authors
  11  * and need not follow the licensing terms described here, provided that
  12  * the new terms are clearly indicated on the first page of each file where
  13  * they apply.
  14  */
  15 #include <errno.h>
  16 #include <time.h>
  17 #include <sys/time.h>
  18 #include <sys/times.h>
  19 #include "glue.h"
  20
  21 /* This is the base address of the mc146818 RTC i/o port. */
  22 #define RTC_PORT 0x400
  23
  24 #define RTC_SECONDS             0x00
  25 #define RTC_SECONDS_ALARM       0x01
  26 #define RTC_MINUTES             0x02
  27 #define RTC_MINUTES_ALARM       0x03
  28 #define RTC_HOURS               0x04
  29 #define RTC_HOURS_ALARM         0x05
  30 #define RTC_DAY_OF_WEEK         0x06
  31 #define RTC_DATE_OF_MONTH       0x07
  32 #define RTC_MONTH               0x08
  33 #define RTC_YEAR                0x09
  34 #define RTC_CONFIG_A            0x0A
  35 #define RTC_CONFIG_B            0x0B
  36 #define RTC_CONFIG_C            0x0C
  37 #define RTC_CONFIG_D            0x0D
  38
  39 /*
  40  * _times -- FIXME
  41  */
  42 int
  43 _times (struct tms *buf)
  44 {
  45   errno = EINVAL;
  46   return (-1);
  47 }
  48
  49 /* Read a value from the RTC port.  */
  50 static unsigned char
  51 rtc_read (unsigned char reg)
  52 {
  53   *(volatile unsigned char *)(RTC_PORT) = reg;
  54   return *(volatile unsigned char *)(RTC_PORT + 1);
  55 }
  56
  57 /* Write a value to the RTC port.  */
  58 static void
  59 rtc_write (unsigned char reg, unsigned char val)
  60 {
  61   *(volatile unsigned char *)(RTC_PORT) = reg;
  62   *(volatile unsigned char *)(RTC_PORT + 1) = val;
  63 }
  64
  65 /* Convert BCD to Decimal.  */
  66 #define BCD2DEC(BYTE) ((((BYTE >> 4) & 0xF) * 10) + (BYTE & 0xF))
  67
  68 /*
  69  * time -- return current time in seconds.
  70  */
  71 time_t
  72 time (time_t *t)
  73 {
  74   struct tm tm;
  75   time_t ret;
  76
  77   tm.tm_sec = BCD2DEC(rtc_read(RTC_SECONDS));
  78   tm.tm_min = BCD2DEC(rtc_read(RTC_MINUTES));
  79   tm.tm_hour = BCD2DEC(rtc_read(RTC_HOURS));
  80   tm.tm_wday = BCD2DEC(rtc_read(RTC_DAY_OF_WEEK)) - 1;
  81   tm.tm_mday = BCD2DEC(rtc_read(RTC_DATE_OF_MONTH));
  82   tm.tm_mon = BCD2DEC(rtc_read(RTC_MONTH)) - 1;
  83   tm.tm_year = BCD2DEC(rtc_read(RTC_YEAR)) + 100;
  84
  85   /* FIXME.  Not really sure how to handle this.  */
  86   tm.tm_isdst = 1;
  87
  88   ret = mktime(&tm);
  89
  90   if (t)
  91     *t = ret;
  92
  93   return ret;
  94 }
  95
  96 /*
  97  * _gettimeofday -- implement in terms of time, which means we can't
  98  * return the microseconds.
  99  */
 100 int
 101 _gettimeofday (struct timeval *tv,
 102         void *tzvp)
 103 {
 104   struct timezone *tz = tzvp;
 105   struct tm tm;
 106   if (tz)
 107     tz->tz_minuteswest = tz->tz_dsttime = 0;
 108
 109   tv->tv_usec = 0;
 110   tv->tv_sec = time(0);
 111
 112   return 0;
 113 }