159 lines
4.0 KiB
C
159 lines
4.0 KiB
C
/*
|
|
* Copyright (C) 1991, 1992, 1995 Linus Torvalds
|
|
*
|
|
* Adapted for PowerPC (PReP) by Gary Thomas
|
|
* Modified by Cort Dougan (cort@cs.nmt.edu).
|
|
* Copied and modified from arch/i386/kernel/time.c
|
|
*
|
|
*/
|
|
#include <linux/errno.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/param.h>
|
|
#include <linux/string.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/time.h>
|
|
#include <linux/timex.h>
|
|
#include <linux/kernel_stat.h>
|
|
#include <linux/mc146818rtc.h>
|
|
#include <linux/init.h>
|
|
#include <linux/bcd.h>
|
|
#include <linux/ioport.h>
|
|
|
|
#include <asm/io.h>
|
|
#include <asm/nvram.h>
|
|
#include <asm/prom.h>
|
|
#include <asm/sections.h>
|
|
#include <asm/time.h>
|
|
|
|
extern spinlock_t rtc_lock;
|
|
|
|
#define NVRAM_AS0 0x74
|
|
#define NVRAM_AS1 0x75
|
|
#define NVRAM_DATA 0x77
|
|
|
|
static int nvram_as1 = NVRAM_AS1;
|
|
static int nvram_as0 = NVRAM_AS0;
|
|
static int nvram_data = NVRAM_DATA;
|
|
|
|
long __init chrp_time_init(void)
|
|
{
|
|
struct device_node *rtcs;
|
|
struct resource r;
|
|
int base;
|
|
|
|
rtcs = of_find_compatible_node(NULL, "rtc", "pnpPNP,b00");
|
|
if (rtcs == NULL)
|
|
rtcs = of_find_compatible_node(NULL, "rtc", "ds1385-rtc");
|
|
if (rtcs == NULL)
|
|
return 0;
|
|
if (of_address_to_resource(rtcs, 0, &r)) {
|
|
of_node_put(rtcs);
|
|
return 0;
|
|
}
|
|
of_node_put(rtcs);
|
|
|
|
base = r.start;
|
|
nvram_as1 = 0;
|
|
nvram_as0 = base;
|
|
nvram_data = base + 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int chrp_cmos_clock_read(int addr)
|
|
{
|
|
if (nvram_as1 != 0)
|
|
outb(addr>>8, nvram_as1);
|
|
outb(addr, nvram_as0);
|
|
return (inb(nvram_data));
|
|
}
|
|
|
|
void chrp_cmos_clock_write(unsigned long val, int addr)
|
|
{
|
|
if (nvram_as1 != 0)
|
|
outb(addr>>8, nvram_as1);
|
|
outb(addr, nvram_as0);
|
|
outb(val, nvram_data);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Set the hardware clock. -- Cort
|
|
*/
|
|
int chrp_set_rtc_time(struct rtc_time *tmarg)
|
|
{
|
|
unsigned char save_control, save_freq_select;
|
|
struct rtc_time tm = *tmarg;
|
|
|
|
spin_lock(&rtc_lock);
|
|
|
|
save_control = chrp_cmos_clock_read(RTC_CONTROL); /* tell the clock it's being set */
|
|
|
|
chrp_cmos_clock_write((save_control|RTC_SET), RTC_CONTROL);
|
|
|
|
save_freq_select = chrp_cmos_clock_read(RTC_FREQ_SELECT); /* stop and reset prescaler */
|
|
|
|
chrp_cmos_clock_write((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT);
|
|
|
|
if (!(save_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
|
|
tm.tm_sec = bin2bcd(tm.tm_sec);
|
|
tm.tm_min = bin2bcd(tm.tm_min);
|
|
tm.tm_hour = bin2bcd(tm.tm_hour);
|
|
tm.tm_mon = bin2bcd(tm.tm_mon);
|
|
tm.tm_mday = bin2bcd(tm.tm_mday);
|
|
tm.tm_year = bin2bcd(tm.tm_year);
|
|
}
|
|
chrp_cmos_clock_write(tm.tm_sec,RTC_SECONDS);
|
|
chrp_cmos_clock_write(tm.tm_min,RTC_MINUTES);
|
|
chrp_cmos_clock_write(tm.tm_hour,RTC_HOURS);
|
|
chrp_cmos_clock_write(tm.tm_mon,RTC_MONTH);
|
|
chrp_cmos_clock_write(tm.tm_mday,RTC_DAY_OF_MONTH);
|
|
chrp_cmos_clock_write(tm.tm_year,RTC_YEAR);
|
|
|
|
/* The following flags have to be released exactly in this order,
|
|
* otherwise the DS12887 (popular MC146818A clone with integrated
|
|
* battery and quartz) will not reset the oscillator and will not
|
|
* update precisely 500 ms later. You won't find this mentioned in
|
|
* the Dallas Semiconductor data sheets, but who believes data
|
|
* sheets anyway ... -- Markus Kuhn
|
|
*/
|
|
chrp_cmos_clock_write(save_control, RTC_CONTROL);
|
|
chrp_cmos_clock_write(save_freq_select, RTC_FREQ_SELECT);
|
|
|
|
spin_unlock(&rtc_lock);
|
|
return 0;
|
|
}
|
|
|
|
void chrp_get_rtc_time(struct rtc_time *tm)
|
|
{
|
|
unsigned int year, mon, day, hour, min, sec;
|
|
|
|
do {
|
|
sec = chrp_cmos_clock_read(RTC_SECONDS);
|
|
min = chrp_cmos_clock_read(RTC_MINUTES);
|
|
hour = chrp_cmos_clock_read(RTC_HOURS);
|
|
day = chrp_cmos_clock_read(RTC_DAY_OF_MONTH);
|
|
mon = chrp_cmos_clock_read(RTC_MONTH);
|
|
year = chrp_cmos_clock_read(RTC_YEAR);
|
|
} while (sec != chrp_cmos_clock_read(RTC_SECONDS));
|
|
|
|
if (!(chrp_cmos_clock_read(RTC_CONTROL) & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
|
|
sec = bcd2bin(sec);
|
|
min = bcd2bin(min);
|
|
hour = bcd2bin(hour);
|
|
day = bcd2bin(day);
|
|
mon = bcd2bin(mon);
|
|
year = bcd2bin(year);
|
|
}
|
|
if (year < 70)
|
|
year += 100;
|
|
tm->tm_sec = sec;
|
|
tm->tm_min = min;
|
|
tm->tm_hour = hour;
|
|
tm->tm_mday = day;
|
|
tm->tm_mon = mon;
|
|
tm->tm_year = year;
|
|
}
|