#ifndef lint
static	char sccsid[] = "@(#)clock.c 1.1 92/07/30 SMI";
#endif

/*
 * Copyright (c) 1988 by Sun Microsystems, Inc.
 */

#include <sys/param.h>
#include <sys/time.h>
#include <sys/kernel.h>

#include <machine/clock.h>
#include <machine/intreg.h>
#include <machine/pte.h>
#include <machine/cpu.h>

#include <sys/user.h>
#include <sys/proc.h>

#ifndef KADB
#include "percpu.h"

void mmu_getpte();
void mmu_setpte();

struct timeval todget();

/*
 * Machine-dependent clock routines.
 *
 * Startrtclock restarts the real-time clock, which provides
 * hardclock interrupts to kern_clock.c.
 *
 * Inittodr initializes the time of day hardware which provides
 * date functions. Its primary function is to use some file
 * system information in case the hardare clock lost state.
 *
 * Resettodr restores the time of day hardware after a time change.
 */

/*
 * These defines convert between binary and bcd representation. They only
 * work on 8 bit unsigned values.
 */
#define	bcdtob(x)	(((x) & 0xF) + 10 * ((x) >> 4))
#define	btobcd(x)	((((x) / 10) << 4) + ((x) % 10))

/*
 * Start the real-time clock.
 */
startrtclock()
{

	/*
	 * We will set things up to interrupt every 1/100 of a second.
	 */
	if (hz != 100)
		panic("startrtclock");
	/*
	 * Start counter in a loop to interrupt hz times/second.
	 * The counter register is initialized to 1 by the HW and not to zero.
	 * Therefore limit should be one more than the  computed number.
	 * Else we will lose 1us/10ms (bugid 1094383).
	 */
	COUNTER->limit10 = (((1000000 / hz) + 1) << CTR_USEC_SHIFT) & CTR_USEC_MASK;
	/*
	 * Turn on level 10 clock intr.
	 */
	set_clk_mode((u_long) IR_ENA_CLK10, (u_long) 0);
}

#endif KADB

/*
 * Enable/disable interrupts for level 10 and/or 14 clock.
 */

u_int	clk10_limit = 0;
u_int	clk14_config = 0;
u_int	clk14_lim[4];
/*
 * clk_state: exptected state at first call.
 */
u_int	clk_state = IR_ENA_CLK10 | IR_ENA_CLK14;

set_clk_mode(on, off)
	u_long on, off;
{
	register u_char dummy;
	register int s;
	int	cpuix, i;

#ifndef KADB
	s = spl7();
#endif

	on &= ~clk_state;	/* dont turn on stuff thats already on */
	off &= clk_state;	/* dont turn off stuff thats already off */
	clk_state ^= on ^ off;	/* modify clock state information */

	/*
	 * Turn off level 10 clock interrupts by setting limit to 0.
	 */
	if (off & IR_ENA_CLK10) {
		clk10_limit = COUNTER->limit10;
		COUNTER->limit10 = 0;
	}

	/*
	 * Turn off level 14 clock interrupts by making them user counters,
	 * and initialize the counters with a magic value.
	 *
	 * This magic value is the minimum double precision floating point
	 * value such that incrementing the tenth least significant bit
	 * corresponds to adding "1.0" to the number. Thus, users can fetch
	 * this value and use it directly as an unbased floating point number
	 * of microseconds. It is up to the user to handle the timer causing
	 * a carry beyond the mantissa, which happens when the system has
	 * been running for 4,398,046.511104 seconds, or just
	 * over seven weeks.
	 */
	if (off & IR_ENA_CLK14) {
		clk14_config = COUNTER->config;
		for (i=0; i<4; i++)
			clk14_lim[i] = COUNTER->cpu[i].timer_msw;
#ifndef	GPROF
		COUNTER->config = TMRALL_CONFIG;
		for (i=0; i<4; i++) {
			COUNTER->cpu[i].timer_lsw = 0x00000000;
			COUNTER->cpu[i].timer_msw = 0x42900000;
		}
#else	GPROF
/* for gprof, "off" means interrupt every millisecond */
		for (i=0; i<4; i++)
			COUNTER->cpu[i].timer_msw = 1000 << 10;
#endif	GPROF
	}

	/*
	 * Clear all interrupts.
	 */
	dummy = COUNTER->limit10;
	for(cpuix = 0;cpuix < 4;cpuix++)
		dummy = COUNTER->cpu[cpuix].timer_msw;
#ifdef lint
	dummy = dummy;
#endif lint

	/*
	 * Turn on level 10 clock interrupts by restoring limit.
	 * If the saved limit was zero, then leave the limit
	 * register alone, since we can't make it any better
	 * than it already is. Ugh.
	 */
	if (on & IR_ENA_CLK10) {
		COUNTER->limit10 = clk10_limit;
	}

	/*
	 * Turn on level 14 clock interrupts by restoring contiguration.
	 */
	if (on & IR_ENA_CLK14) {
		COUNTER->config = clk14_config;
		for (i=0; i<4; i++)
			COUNTER->cpu[i].timer_msw = clk14_lim[i];
	}
#ifndef KADB
	(void) splx(s);
#endif
}

#ifndef KADB			/* to EOF */

int dosynctodr = 1;		/* if true, sync UNIX time to TOD */
int clkdrift = 0;		/* if true, show UNIX & TOD sync differences */
int synctodrval = 30;		/* number of seconds between synctodr */
extern long timedelta;
extern int tickadj;
extern int tickdelta;

#ifndef	ABS
#define	ABS(x)	((x) < 0? -(x) : (x))
#endif	ABS

int	todsyncat = 0;

synctodr()
{
	struct timeval tv;
	int deltat, s;
	int sch = synctodrval * hz - 2;

/*
 * If timedelta is non-zero, assume someone who
 * knows better is already adjusting the time.
 * Don't assume that this nice person is going
 * to hang around forever, tho.
 */
	if (dosynctodr && timedelta == 0) {
		s = splclock();
		tv = todget();
/*
 * Sorry about the gotos, but in this case they are more clear than
 * nested conditionals or a do { ... } while (0); construct with
 * multiple break statements, or replication of the splx() and
 * timeout() code.  All of the gotos here branch down to the bottom of
 * the current conditional, just above where the priority is restored.
 */

/*
 * Several machines have clock chips that only give us
 * one second of precision; for them, we must hang out
 * until the clock changes. When this happens, we can
 * assume we are near (within 10ms) the beginning of
 * the second, and apply the normal algorithm.
 *
 * Systems with higher precision clocks are not hurt by
 * having this run, the overhead is nearly zero.
 */
		if (!todsyncat)
			todsyncat = tv.tv_sec;
		if (todsyncat == tv.tv_sec) {
			sch = 1;
			goto bottom;
		}
/*
 * Sanity check: if todget is returning zeros, bitch and turn off
 * clock synchronization. The old code would flail about madly.
 */
		if (tv.tv_sec == 0) {
			printf("synctodr: unable to read clock chip\n");
			dosynctodr = 0;
			goto bottom;
		}
/*
 * Sanity check: if the two clocks are out of sync by more than
 * about 2000 seconds, complain and turn off sync; continuing
 * would result in integer overflows resulting in synchronizing
 * to the wrong time.
 */
		deltat = tv.tv_sec - time.tv_sec;
		if (ABS(deltat) > 2000) {
			printf("synctodr: unable to sync, delta=%d\n", deltat);
			dosynctodr = 0;
			goto bottom;
		}
/*
 * Calculate how far off we are. If we are out by more than
 * one clock tick, set up timedelta and tickdelta so that
 * hardclock() will increment the software clock a bit fast
 * or a bit slow. How fast or how slow is determined by tickadj,
 * the number of microseconds of correction applied each tick.
 */
		deltat = deltat * 1000000 + tv.tv_usec - time.tv_usec;

		if (ABS(deltat) > 1000000 / hz) {
			timedelta = deltat;
			tickdelta = tickadj; /* standard slew rate */
			if (clkdrift)
				printf("<[%d]> ", deltat / 1000);
		}
		todsyncat = 0;
	bottom:
		(void) splx(s);
	} else
		todsyncat = 0;
	timeout(synctodr, (caddr_t)0, sch);
}

/*
 * Initialize the system time, based on the time base which is, e.g. from
 * a filesystem.  A base of -1 means the file system doesn't keep time.
 */
inittodr(base)
	time_t base;
{
	register long deltat;
	int s;

	s = splclock();
	time = todget();
	(void) splx(s);
	if (time.tv_sec < SECYR) {
		if (base == -1)
			time.tv_sec = (87 - YRREF) * SECYR;	/* ~1987 */
		else
			time.tv_sec = base;
		printf("WARNING: TOD clock not initialized");
		resettodr();
		goto check;
	}
	if (base == -1)
		goto out;
	if (base < (87 - YRREF) * SECYR) {			/* ~1987 */
		printf("WARNING: preposterous time in file system");
		goto check;
	}
	deltat = time.tv_sec - base;
	/*
	 * See if we gained/lost two or more days;
	 * if so, assume something is amiss.
	 */
	if (deltat < 0)
		deltat = -deltat;
	if (deltat < 2*SECDAY)
		goto out;
	printf("WARNING: clock %s %d days",
	    time.tv_sec < base ? "lost" : "gained", deltat / SECDAY);
check:
	printf(" -- CHECK AND RESET THE DATE!\n");
out:
	if (dosynctodr)
		timeout(synctodr, (caddr_t)0, synctodrval * hz);
}

/*
 * For Sun-4c, we use the Mostek 48T02 for the time-of-day device, and
 * a separate timer circuit for real time interrupts.
 */

static u_int monthsec[12] = {
	31 * SECDAY,	/* Jan */
	28 * SECDAY,	/* Feb */
	31 * SECDAY,	/* Mar */
	30 * SECDAY,	/* Apr */
	31 * SECDAY,	/* May */
	30 * SECDAY,	/* Jun */
	31 * SECDAY,	/* Jul */
	31 * SECDAY,	/* Aug */
	30 * SECDAY,	/* Sep */
	31 * SECDAY,	/* Oct */
	30 * SECDAY,	/* Nov */
	31 * SECDAY	/* Dec */
};

#define	MONTHSEC(mon, yr)	\
	(((((yr) % 4) == 0) && ((mon) == 2))? 29*SECDAY : monthsec[(mon) - 1])

/*
 * Set the TOD based on the argument value; used when the TOD
 * has a preposterous value and also when the time is reset
 * by the settimeofday system call. We run at splclock() to
 * avoid synctodr() from running and getting confused.
 */
resettodr()
{
	register int t;
	u_short sec, min, hour, day, mon, weekday, year;
	int s;
#if !defined(sun4m)
	struct pte pte;
	unsigned int saveprot;
#endif

	s = splclock();

	t = time.tv_sec;
	/*
	 * Figure out the weekday
	 */
	weekday = (t/(60*60*24) + 2) % 7 + 1;	/* 1..7 */
	/*
	 * Figure out the (adjusted) year
	 */
	for (year = (YRREF - YRBASE); t > SECYEAR(year); year++)
		t -= SECYEAR(year);

	/*
	 * Figure out what month this is by subtracting off
	 * time per month, adjust for leap year if appropriate.
	 */
	for (mon = 1; t >= 0; mon++)
		t -= MONTHSEC(mon, year);

	mon--;				/* back off one month */
	t += MONTHSEC(mon, year);

	sec = t % 60;			/* seconds */
	t /= 60;
	min = t % 60;			/* minutes */
	t /= 60;
	hour = t % 24;			/* hours (24 hour format) */
	day = t / 24;			/* day of the month */
	day++;				/* adjust to start at 1 */

#if !defined(sun4m)
	/* write-enable the eeprom */
	mmu_getpte((addr_t)CLOCK, &pte);
	saveprot = pte.AccessPermissions;
	pte.AccessPermissions = MMU_STD_SRWUR;
	mmu_setpte((addr_t)CLOCK, pte);
#endif
	CLOCK->clk_ctrl |= CLK_CTRL_WRITE;	/* allow writes */
	CLOCK->clk_sec = btobcd(sec) & CLK_SEC_MASK;
	CLOCK->clk_min = btobcd(min) & CLK_MIN_MASK;
	CLOCK->clk_hour = btobcd(hour) & CLK_HOUR_MASK;
	CLOCK->clk_weekday = btobcd(weekday) & CLK_WEEKDAY_MASK;
	CLOCK->clk_day = btobcd(day) & CLK_DAY_MASK;
	CLOCK->clk_month = btobcd(mon) & CLK_MONTH_MASK;
	CLOCK->clk_year = btobcd(year);
	CLOCK->clk_ctrl &= ~CLK_CTRL_WRITE;	/* load values */
#if !defined(sun4m)
	/* Now write protect it, preserving the new modify/ref bits */
	mmu_getpte((addr_t)CLOCK, &pte);
	pte.AccessPermissions = saveprot;
	mmu_setpte((addr_t)CLOCK, pte);
#endif

	timedelta = 0;		/* destroy any time delta */

	(void) splx(s);
}

/*
 * Read the current time from the clock chip and convert to UNIX form.
 * Assumes that the year in the clock chip is valid.
 * Assumes we're called at splclock().
 */
struct timeval
todget()
{
	struct timeval tv;
	struct mostek48T02 now;
	u_int usec;
	register int i, t = 0;
	u_short year;
#if !defined(sun4m)
	struct pte pte;
	unsigned int saveprot;
#endif

	/*
	 * Turn off updates so we can read the clock cleanly. Then read
	 * all the registers into a temp, and reenable updates.
	 */
#if !defined(sun4m)
	/* write-enable the eeprom */
	mmu_getpte((addr_t)CLOCK, &pte);
	saveprot = pte.AccessPermissions;
	pte.AccessPermissions = MMU_STD_SRWUR;
	mmu_setpte((addr_t)CLOCK, pte);
#endif
	CLOCK->clk_ctrl |= CLK_CTRL_READ;
	now.clk_sec = bcdtob(CLOCK->clk_sec & CLK_SEC_MASK);
	now.clk_min = bcdtob(CLOCK->clk_min & CLK_MIN_MASK);
	now.clk_hour = bcdtob(CLOCK->clk_hour & CLK_HOUR_MASK);
	now.clk_weekday = bcdtob(CLOCK->clk_weekday & CLK_WEEKDAY_MASK);
	now.clk_day = bcdtob(CLOCK->clk_day & CLK_DAY_MASK);
	now.clk_month = bcdtob(CLOCK->clk_month & CLK_MONTH_MASK);
	now.clk_year = bcdtob(CLOCK->clk_year);
	CLOCK->clk_ctrl &= ~CLK_CTRL_READ;
#if !defined(sun4m)
	/* Now write protect it, preserving the new modify/ref bits */
	mmu_getpte((addr_t)CLOCK, &pte);
	pte.AccessPermissions = saveprot;
	mmu_setpte((addr_t)CLOCK, pte);
#endif

	/*
	 * Note: since the chip only keeps time to the
	 * nearest second, we have no guess as to where
	 * within the second we actually fall. The sync
	 * algorithm has been modified to handle this.
	 */
	usec = 0;

	/*
	 * If any of the values are bogus, the tod is not initialized.
	 */
	if (now.clk_month < 1 || now.clk_month > 12 ||
	    now.clk_day < 1 || now.clk_day > 31 ||
	    now.clk_min > 59 || now.clk_sec > 59 ||
	    now.clk_year < (YRREF - YRBASE)) {
		tv.tv_sec = 0;
		tv.tv_usec = 0;
		return (tv);
	}

	/*
	 * Add the number of seconds for each year onto our time t.
	 * We start at YRREF - YRBASE (which is the chip's value
	 * for UNIX's YRREF year), and count up to the year value given
	 * by the chip, adding each years seconds value to the Unix
	 * time value we are calculating.
	 */
	for (year = YRREF - YRBASE; year < now.clk_year; year++)
		t += SECYEAR(year);

	/*
	 * Now add in the seconds for each month that has gone
	 * by this year, adjusting for leap year if appropriate.
	 */
	for (i = 1; i < now.clk_month; i++)
		t += MONTHSEC(i, year);

	t += (now.clk_day - 1) * SECDAY;
	t += now.clk_hour * (60*60);
	t += now.clk_min * 60;
	t += now.clk_sec;

	/*
	 * If t is negative, assume bogus time
	 * (year was too large) and use 0 seconds.
	 * XXX - tv_sec and tv_usec should be unsigned.
	 */
	if (t < 0) {
		tv.tv_sec = 0;
		tv.tv_usec = 0;
	} else {
		tv.tv_sec = t;
		tv.tv_usec = usec;
	}
	return (tv);
}

/************************************************************************
 *	From here down should really be an "led device driver".
 *
 * right four leds correspond to low four bits of data
 * and are used for "this cpu exists", one lite per cpu
 *
 * middle four leds correspond to next four bits of data
 * and are used for "system is running", rolling ball.
 * When the system is handling a lot of interrupts, the
 * ball rolls slower (we get this for free).
 *
 * left four leds correspond to next four bits of data
 * and are used for "this cpu busy", one lite per cpu
 */
unsigned	phasepattern[] = {
 	0x010,			/* .......#.... */
	0x020,			/* ......#..... */
	0x040,			/* .....#...... */
	0x080,			/* ....#....... */
	0x040,			/* .....#...... */
	0x020,			/* ......#..... */
};

#define	MAXPHASE	(sizeof phasepattern / sizeof phasepattern[0])

int	ledframespersec = 100;	/* led update frequency */
int	ledframesperstep = 10;	/* frames for each phase change */

#ifdef	MULTIPROCESSOR
#include <machine/psl.h>

extern	int	nmod;
#endif	MULTIPROCESSOR

int
ledping(ptr)
	int	       *ptr;
{
	extern void     set_diagled();
	extern int	cpu;
	static int      frame = 0;
	static int      step = 0;
	int             value;
	int		s;
#ifdef	MULTIPROCESSOR
	int		ix;
#endif	MULTIPROCESSOR

	s = splclock();
	untimeout(ledping, (caddr_t) 0);

	switch(cpu) {
#ifdef	SUN4M_690
	case CPU_SUN4M_690:
		if (ptr) {
			value = *ptr;
		} else {
			if (frame < 1) {
				frame = ledframesperstep;
				if (step < 1)
					step = MAXPHASE - 1;
				else
					step = step - 1;
			} else {
				frame--;
			}

			value = phasepattern[step];
#ifndef	MULTIPROCESSOR
			value |= 1;
#else	MULTIPROCESSOR
			for (ix = 0; ix < nmod; ++ix) {
				if (PerCPU[ix].cpu_exists) {
/*
 *	LED Layout for MULTIPROCESSOR mode:
 *
 *	DIAGNOSTIC LEDs
 *	@@@@ @@@@ @@@@
 *	|||| |||| ||||_ system mode (one per cpu, "3210")
 *	|||| ||||______ system is alive (bouncing LED)
 *	||||___________ user mode (one per cpu, "3210")
 *
 */
					if (PerCPU[ix].cpu_supv)
						value |= 0x001 << ix;
					else if (!PerCPU[ix].cpu_idle)
						value |= 0x100 << ix;
				}
			}
#endif	MULTIPROCESSOR
		}
		set_diagled(value);
		break;
#endif	SUN4M_690

#ifdef	SUN4M_50
	case CPU_SUN4M_50:
		if (ptr) {
			set_diagled(*ptr);	/* as requested ... */
		} else {
			set_diagled(1);		/* turn it on */
		}
		break;
#endif	SUN4M_50

	default:
		break;	/* unknown cpu, do nothing */
	}
	timeout(ledping, (caddr_t) 0, hz / ledframespersec);
	(void)splx(s);
}
#endif	KADB