LXR linux/arch/mn10300/kernel/rtc.c

   1/* MN10300 RTC management
   2 *
   3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   4 * Written by David Howells (dhowells@redhat.com)
   5 *
   6 * This program is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU General Public Licence
   8 * as published by the Free Software Foundation; either version
   9 * 2 of the Licence, or (at your option) any later version.
  10 */
  11#include <linux/kernel.h>
  12#include <linux/module.h>
  13#include <linux/init.h>
  14#include <linux/mc146818rtc.h>
  15#include <linux/ioport.h>
  16#include <linux/platform_device.h>
  17
  18#include <asm/rtc-regs.h>
  19#include <asm/rtc.h>
  20
  21DEFINE_SPINLOCK(rtc_lock);
  22EXPORT_SYMBOL(rtc_lock);
  23
  24static const __initdata struct resource res[] = {
  25        DEFINE_RES_IO(RTC_PORT(0), RTC_IO_EXTENT),
  26        DEFINE_RES_IRQ(RTC_IRQ),
  27};
  28
  29/*
  30 * calibrate the TSC clock against the RTC
  31 */
  32void __init calibrate_clock(void)
  33{
  34        unsigned char status;
  35
  36        /* make sure the RTC is running and is set to operate in 24hr mode */
  37        status = RTSRC;
  38        RTCRB |= RTCRB_SET;
  39        RTCRB |= RTCRB_TM_24HR;
  40        RTCRB &= ~RTCRB_DM_BINARY;
  41        RTCRA |= RTCRA_DVR;
  42        RTCRA &= ~RTCRA_DVR;
  43        RTCRB &= ~RTCRB_SET;
  44
  45        platform_device_register_simple("rtc_cmos", -1, res, ARRAY_SIZE(res));
  46}
  47