/* linux/arch/sparc/kernel/time.c
*
* Copyright (C) 1995 David S. Miller (davem@davemloft.net)
* Copyright (C) 1996 Thomas K. Dyas (tdyas@eden.rutgers.edu)
*
* Chris Davis (cdavis@cois.on.ca) 03/27/1998
* Added support for the intersil on the sun4/4200
*
* Gleb Raiko (rajko@mech.math.msu.su) 08/18/1998
* Support for MicroSPARC-IIep, PCI CPU.
*
* This file handles the Sparc specific time handling details.
*
* 1997-09-10 Updated NTP code according to technical memorandum Jan '96
* "A Kernel Model for Precision Timekeeping" by Dave Mills
*/
#include <linux/errno.h>
#include <linux/module.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/rtc.h>
#include <linux/rtc/m48t59.h>
#include <linux/timex.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/ioport.h>
#include <linux/profile.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <asm/oplib.h>
#include <asm/timer.h>
#include <asm/system.h>
#include <asm/irq.h>
#include <asm/io.h>
#include <asm/idprom.h>
#include <asm/machines.h>
#include <asm/page.h>
#include <asm/pcic.h>
#include <asm/irq_regs.h>
#include "irq.h"
DEFINE_SPINLOCK(rtc_lock);
static int set_rtc_mmss(unsigned long);
static int sbus_do_settimeofday(struct timespec *tv);
unsigned long profile_pc(struct pt_regs *regs)
{
extern char __copy_user_begin[], __copy_user_end[];
extern char __atomic_begin[], __atomic_end[];
extern char __bzero_begin[], __bzero_end[];
unsigned long pc = regs->pc;
if (in_lock_functions(pc) ||
(pc >= (unsigned long) __copy_user_begin &&
pc < (unsigned long) __copy_user_end) ||
(pc >= (unsigned long) __atomic_begin &&
pc < (unsigned long) __atomic_end) ||
(pc >= (unsigned long) __bzero_begin &&
pc < (unsigned long) __bzero_end))
pc = regs->u_regs[UREG_RETPC];
return pc;
}
EXPORT_SYMBOL(profile_pc);
__volatile__ unsigned int *master_l10_counter;
/*
* timer_interrupt() needs to keep up the real-time clock,
* as well as call the "do_timer()" routine every clocktick
*/
#define TICK_SIZE (tick_nsec / 1000)
static irqreturn_t timer_interrupt(int dummy, void *dev_id)
{
/* last time the cmos clock got updated */
static long last_rtc_update;
#ifndef CONFIG_SMP
profile_tick(CPU_PROFILING);
#endif
/* Protect counter clear so that do_gettimeoffset works */
write_seqlock(&xtime_lock);
clear_clock_irq();
do_timer(1);
/* Determine when to update the Mostek clock. */
if (ntp_synced() &&
xtime.tv_sec > last_rtc_update + 660 &&
(xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 &&
(xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) {
if (set_rtc_mmss(xtime.tv_sec) == 0)
last_rtc_update = xtime.tv_sec;
else
last_rtc_update = xtime.tv_sec - 600; /* do it again in 60 s */
}
write_sequnlock(&xtime_lock);
#ifndef CONFIG_SMP
update_process_times(user_mode(get_irq_regs()));
#endif
return IRQ_HANDLED;
}
static unsigned char mostek_read_byte(struct device *dev, u32 ofs)
{
struct platform_device *pdev = to_platform_device(dev);
struct m48t59_plat_data *pdata = pdev->dev.platform_data;
void __iomem *regs = pdata->ioaddr;
unsigned char val = readb(regs + ofs);
/* the year 0 is 1968 */
if (ofs == pdata->offset + M48T59_YEAR) {
val += 0x68;
if ((val & 0xf) > 9)
val += 6;
}
return val;
}
static void mostek_write_byte(struct device *dev, u32 ofs, u8 val)
{
struct platform_device *pdev = to_platform_device(dev);
struct m48t59_plat_data *pdata = pdev->dev.platform_data;
void __iomem *regs = pdata->ioaddr;
if (ofs == pdata->offset + M48T59_YEAR) {
if (val < 0x68)
val += 0x32;
else
val -= 0x68;
if ((val & 0xf) > 9)
val += 6;
if ((val & 0xf0) > 0x9A)
val += 0x60;
}
writeb(val, regs + ofs);
}
static struct m48t59_plat_data m48t59_data = {
.read_byte = mostek_read_byte,
.write_byte = mostek_write_byte,
};
/* resource is set at runtime */
static struct platform_device m48t59_rtc = {
.name = "rtc-m48t59",
.id = 0,
.num_resources = 1,
.dev = {
.platform_data = &m48t59_data,
},
};
static int __devinit clock_probe(struct of_device *op, const struct of_device_id *match)
{
struct device_node *dp = op->node;
const char *model = of_get_property(dp, "model", NULL);
if (!model)
return -ENODEV;
m48t59_rtc.resource = &op->resource[0];
if (!strcmp(model, "mk48t02")) {
/* Map the clock register io area read-only */
m48t59_data.ioaddr = of_ioremap(&op->resource[0], 0,
2048, "rtc-m48t59");
m48t59_data.type = M48T59RTC_TYPE_M48T02;
} else if (!strcmp(model, "mk48t08")) {
m48t59_data.ioaddr = of_ioremap(&op->resource[0], 0,
8192, "rtc-m48t59");
m48t59_data.type = M48T59RTC_TYPE_M48T08;
} else
return -ENODEV;
if (platform_device_register(&m48t59_rtc) < 0)
printk(KERN_ERR "Registering RTC device failed\n");
return 0;
}
static struct of_device_id __initdata clock_match[] = {
{
.name = "eeprom",
},
{},
};
static struct of_platform_driver clock_driver = {
.match_table = clock_match,
.probe = clock_probe,
.driver = {
.name = "rtc",
},
};
/* Probe for the mostek real time clock chip. */
static int __init clock_init(void)
{
return of_register_driver(&clock_driver, &of_platform_bus_type);
}
/* Must be after subsys_initcall() so that busses are probed. Must
* be before device_initcall() because things like the RTC driver
* need to see the clock registers.
*/
fs_initcall(clock_init);
static void __init sbus_time_init(void)
{
BTFIXUPSET_CALL(bus_do_settimeofday, sbus_do_settimeofday, BTFIXUPCALL_NORM);
btfixup();
sparc_init_timers(timer_interrupt);
/* Now that OBP ticker has been silenced, it is safe to enable IRQ. */
local_irq_enable();
}
void __init time_init(void)
{
#ifdef CONFIG_PCI
extern void pci_time_init(void);
if (pcic_present()) {
pci_time_init();
return;
}
#endif
sbus_time_init();
}
static inline unsigned long do_gettimeoffset(void)
{
unsigned long val = *master_l10_counter;
unsigned long usec = (val >> 10) & 0x1fffff;
/* Limit hit? */
if (val & 0x80000000)
usec += 1000000 / HZ;
return usec;
}
/* Ok, my cute asm atomicity trick doesn't work anymore.
* There are just too many variables that need to be protected
* now (both members of xtime, et al.)
*/
void do_gettimeofday(struct timeval *tv)
{
unsigned long flags;
unsigned long seq;
unsigned long usec, sec;
unsigned long max_ntp_tick = tick_usec - tickadj;
do {
seq = read_seqbegin_irqsave(&xtime_lock, flags);
usec = do_gettimeoffset();
/*
* If time_adjust is negative then NTP is slowing the clock
* so make sure not to go into next possible interval.
* Better to lose some accuracy than have time go backwards..
*/
if (unlikely(time_adjust < 0))
usec = min(usec, max_ntp_tick);
sec = xtime.tv_sec;
usec += (xtime.tv_nsec / 1000);
} while (read_seqretry_irqrestore(&xtime_lock, seq, flags));
while (usec >= 1000000) {
usec -= 1000000;
sec++;
}
tv->tv_sec = sec;
tv->tv_usec = usec;
}
EXPORT_SYMBOL(do_gettimeofday);
int do_settimeofday(struct timespec *tv)
{
int ret;
write_seqlock_irq(&xtime_lock);
ret = bus_do_settimeofday(tv);
write_sequnlock_irq(&xtime_lock);
clock_was_set();
return ret;
}
EXPORT_SYMBOL(do_settimeofday);
static int sbus_do_settimeofday(struct timespec *tv)
{
time_t wtm_sec, sec = tv->tv_sec;
long wtm_nsec, nsec = tv->tv_nsec;
if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
return -EINVAL;
/*
* This is revolting. We need to set "xtime" correctly. However, the
* value in this location is the value at the most recent update of
* wall time. Discover what correction gettimeofday() would have
* made, and then undo it!
*/
nsec -= 1000 * do_gettimeoffset();
wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);
wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec);
set_normalized_timespec(&xtime, sec, nsec);
set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
ntp_clear();
return 0;
}
static int set_rtc_mmss(unsigned long secs)
{
struct rtc_device *rtc = rtc_class_open("rtc0");
int err = -1;
if (rtc) {
err = rtc_set_mmss(rtc, secs);
rtc_class_close(rtc);
}
return err;
}
