/*
* Support for periodic interrupts (100 per second) and for getting
* the current time from the RTC on Power Macintoshes.
*
* We use the decrementer register for our periodic interrupts.
*
* Paul Mackerras August 1996.
* Copyright (C) 1996 Paul Mackerras.
* Copyright (C) 2003-2005 Benjamin Herrenschmidt.
*
*/
#include <linux/config.h>
#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/init.h>
#include <linux/time.h>
#include <linux/adb.h>
#include <linux/pmu.h>
#include <linux/interrupt.h>
#include <asm/sections.h>
#include <asm/prom.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/machdep.h>
#include <asm/time.h>
#include <asm/nvram.h>
#include <asm/smu.h>
#undef DEBUG
#ifdef DEBUG
#define DBG(x...) printk(x)
#else
#define DBG(x...)
#endif
/* Apparently the RTC stores seconds since 1 Jan 1904 */
#define RTC_OFFSET 2082844800
/*
* Calibrate the decrementer frequency with the VIA timer 1.
*/
#define VIA_TIMER_FREQ_6 4700000 /* time 1 frequency * 6 */
extern struct timezone sys_tz;
extern void to_tm(int tim, struct rtc_time * tm);
void __pmac pmac_get_rtc_time(struct rtc_time *tm)
{
switch(sys_ctrler) {
#ifdef CONFIG_ADB_PMU
case SYS_CTRLER_PMU: {
/* TODO: Move that to a function in the PMU driver */
struct adb_request req;
unsigned int now;
if (pmu_request(&req, NULL, 1, PMU_READ_RTC) < 0)
return;
pmu_wait_complete(&req);
if (req.reply_len != 4)
printk(KERN_ERR "pmac_get_rtc_time: PMU returned a %d"
" bytes reply\n", req.reply_len);
now = (req.reply[0] << 24) + (req.reply[1] << 16)
+ (req.reply[2] << 8) + req.reply[3];
DBG("get: %u -> %u\n", (int)now, (int)(now - RTC_OFFSET));
now -= RTC_OFFSET;
to_tm(now, tm);
tm->tm_year -= 1900;
tm->tm_mon -= 1;
DBG("-> tm_mday: %d, tm_mon: %d, tm_year: %d, %d:%02d:%02d\n",
tm->tm_mday, tm->tm_mon, tm->tm_year,
tm->tm_hour, tm->tm_min, tm->tm_sec);
break;
}
#endif /* CONFIG_ADB_PMU */
#ifdef CONFIG_PMAC_SMU
case SYS_CTRLER_SMU:
smu_get_rtc_time(tm);
break;
#endif /* CONFIG_PMAC_SMU */
default:
;
}
}
int __pmac pmac_set_rtc_time(struct rtc_time *tm)
{
switch(sys_ctrler) {
#ifdef CONFIG_ADB_PMU
case SYS_CTRLER_PMU: {
/* TODO: Move that to a function in the PMU driver */
struct adb_request req;
unsigned int nowtime;
DBG("set: tm_mday: %d, tm_mon: %d, tm_year: %d,"
" %d:%02d:%02d\n",
tm->tm_mday, tm->tm_mon, tm->tm_year,
tm->tm_hour, tm->tm_min, tm->tm_sec);
nowtime = mktime(tm->tm_year + 1900, tm->tm_mon + 1,
tm->tm_mday, tm->tm_hour, tm->tm_min,
tm->tm_sec);
DBG("-> %u -> %u\n", (int)nowtime,
(int)(nowtime + RTC_OFFSET));
nowtime += RTC_OFFSET;
if (pmu_request(&req, NULL, 5, PMU_SET_RTC,
nowtime >> 24, nowtime >> 16,
nowtime >> 8, nowtime) < 0)
return -ENXIO;
pmu_wait_complete(&req);
if (req.reply_len != 0)
printk(KERN_ERR "pmac_set_rtc_time: PMU returned a %d"
" bytes reply\n", req.reply_len);
return 0;
}
#endif /* CONFIG_ADB_PMU */
#ifdef CONFIG_PMAC_SMU
case SYS_CTRLER_SMU:
return smu_set_rtc_time(tm);
#endif /* CONFIG_PMAC_SMU */
default:
return -ENODEV;
}
}
void __init pmac_get_boot_time(struct rtc_time *tm)
{
pmac_get_rtc_time(tm);
#ifdef disabled__CONFIG_NVRAM
s32 delta = 0;
int dst;
delta = ((s32)pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0x9)) << 16;
delta |= ((s32)pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0xa)) << 8;
delta |= pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0xb);
if (delta & 0x00800000UL)
delta |= 0xFF000000UL;
dst = ((pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0x8) & 0x80) != 0);
printk("GMT Delta read from XPRAM: %d minutes, DST: %s\n", delta/60,
dst ? "on" : "off");
#endif
}
/*
* Query the OF and get the decr frequency.
* FIXME: merge this with generic_calibrate_decr
*/
void __init pmac_calibrate_decr(void)
{
struct device_node *cpu;
unsigned int freq, *fp;
struct div_result divres;
/*
* The cpu node should have a timebase-frequency property
* to tell us the rate at which the decrementer counts.
*/
cpu = find_type_devices("cpu");
if (cpu == 0)
panic("can't find cpu node in time_init");
fp = (unsigned int *) get_property(cpu, "timebase-frequency", NULL);
if (fp == 0)
panic("can't get cpu timebase frequency");
freq = *fp;
printk("time_init: decrementer frequency = %u.%.6u MHz\n",
freq/1000000, freq%1000000);
tb_ticks_per_jiffy = freq / HZ;
tb_ticks_per_sec = tb_ticks_per_jiffy * HZ;
tb_ticks_per_usec = freq / 1000000;
tb_to_us = mulhwu_scale_factor(freq, 1000000);
div128_by_32( 1024*1024, 0, tb_ticks_per_sec, &divres );
tb_to_xs = divres.result_low;
ppc_tb_freq = freq;
fp = (unsigned int *)get_property(cpu, "clock-frequency", NULL);
if (fp == 0)
panic("can't get cpu processor frequency");
ppc_proc_freq = *fp;
setup_default_decr();
}
