58 lines
1.2 KiB
C
58 lines
1.2 KiB
C
/*
|
|
* arch/arm/mach-footbridge/isa-rtc.c
|
|
*
|
|
* Copyright (C) 1998 Russell King.
|
|
* Copyright (C) 1998 Phil Blundell
|
|
*
|
|
* CATS has a real-time clock, though the evaluation board doesn't.
|
|
*
|
|
* Changelog:
|
|
* 21-Mar-1998 RMK Created
|
|
* 27-Aug-1998 PJB CATS support
|
|
* 28-Dec-1998 APH Made leds optional
|
|
* 20-Jan-1999 RMK Started merge of EBSA285, CATS and NetWinder
|
|
* 16-Mar-1999 RMK More support for EBSA285-like machines with RTCs in
|
|
*/
|
|
|
|
#define RTC_PORT(x) (0x70+(x))
|
|
#define RTC_ALWAYS_BCD 0
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/mc146818rtc.h>
|
|
#include <linux/bcd.h>
|
|
#include <linux/io.h>
|
|
|
|
#include "common.h"
|
|
|
|
void __init isa_rtc_init(void)
|
|
{
|
|
int reg_d, reg_b;
|
|
|
|
/*
|
|
* Probe for the RTC.
|
|
*/
|
|
reg_d = CMOS_READ(RTC_REG_D);
|
|
|
|
/*
|
|
* make sure the divider is set
|
|
*/
|
|
CMOS_WRITE(RTC_REF_CLCK_32KHZ, RTC_REG_A);
|
|
|
|
/*
|
|
* Set control reg B
|
|
* (24 hour mode, update enabled)
|
|
*/
|
|
reg_b = CMOS_READ(RTC_REG_B) & 0x7f;
|
|
reg_b |= 2;
|
|
CMOS_WRITE(reg_b, RTC_REG_B);
|
|
|
|
if ((CMOS_READ(RTC_REG_A) & 0x7f) == RTC_REF_CLCK_32KHZ &&
|
|
CMOS_READ(RTC_REG_B) == reg_b) {
|
|
/*
|
|
* We have a RTC. Check the battery
|
|
*/
|
|
if ((reg_d & 0x80) == 0)
|
|
printk(KERN_WARNING "RTC: *** warning: CMOS battery bad\n");
|
|
}
|
|
}
|