[thirdparty/u-boot.git] / arch / arm / cpu / arm926ejs / omap / timer.c

/*
 * (C) Copyright 2003
 * Texas Instruments <www.ti.com>
 *
 * (C) Copyright 2002
 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Marius Groeger <mgroeger@sysgo.de>
 *
 * (C) Copyright 2002
 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Alex Zuepke <azu@sysgo.de>
 *
 * (C) Copyright 2002-2004
 * Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
 *
 * (C) Copyright 2004
 * Philippe Robin, ARM Ltd. <philippe.robin@arm.com>
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <asm/io.h>

#define TIMER_CLOCK	(CONFIG_SYS_CLK_FREQ / (2 << CONFIG_SYS_PTV))
#define TIMER_LOAD_VAL	0xffffffff

/* macro to read the 32 bit timer */
#define READ_TIMER	readl(CONFIG_SYS_TIMERBASE+8) \
			/ (TIMER_CLOCK / CONFIG_SYS_HZ)

DECLARE_GLOBAL_DATA_PTR;

#define timestamp gd->arch.tbl
#define lastdec gd->arch.lastinc

int timer_init (void)
{
	int32_t val;

	/* Start the decrementer ticking down from 0xffffffff */
	*((int32_t *) (CONFIG_SYS_TIMERBASE + LOAD_TIM)) = TIMER_LOAD_VAL;
	val = MPUTIM_ST | MPUTIM_AR | MPUTIM_CLOCK_ENABLE | (CONFIG_SYS_PTV << MPUTIM_PTV_BIT);
	*((int32_t *) (CONFIG_SYS_TIMERBASE + CNTL_TIMER)) = val;

	/* init the timestamp and lastdec value */
	reset_timer_masked();

	return 0;
}

/*
 * timer without interrupts
 */
ulong get_timer (ulong base)
{
	return get_timer_masked () - base;
}

/* delay x useconds AND preserve advance timestamp value */
void __udelay (unsigned long usec)
{
	ulong tmo, tmp;

	if(usec >= 1000){		/* if "big" number, spread normalization to seconds */
		tmo = usec / 1000;	/* start to normalize for usec to ticks per sec */
		tmo *= CONFIG_SYS_HZ;	/* find number of "ticks" to wait to achieve target */
		tmo /= 1000;		/* finish normalize. */
	}else{				/* else small number, don't kill it prior to HZ multiply */
		tmo = usec * CONFIG_SYS_HZ;
		tmo /= (1000*1000);
	}

	tmp = get_timer (0);		/* get current timestamp */
	if( (tmo + tmp + 1) < tmp )	/* if setting this fordward will roll time stamp */
		reset_timer_masked ();	/* reset "advancing" timestamp to 0, set lastdec value */
	else
		tmo += tmp;		/* else, set advancing stamp wake up time */

	while (get_timer_masked () < tmo)/* loop till event */
		/*NOP*/;
}

void reset_timer_masked (void)
{
	/* reset time */
	lastdec = READ_TIMER;  /* capure current decrementer value time */
	timestamp = 0;	       /* start "advancing" time stamp from 0 */
}

ulong get_timer_masked (void)
{
	ulong now = READ_TIMER;		/* current tick value */

	if (lastdec >= now) {		/* normal mode (non roll) */
		/* normal mode */
		timestamp += lastdec - now; /* move stamp fordward with absoulte diff ticks */
	} else {			/* we have overflow of the count down timer */
		/* nts = ts + ld + (TLV - now)
		 * ts=old stamp, ld=time that passed before passing through -1
		 * (TLV-now) amount of time after passing though -1
		 * nts = new "advancing time stamp"...it could also roll and cause problems.
		 */
		timestamp += lastdec + (TIMER_LOAD_VAL / (TIMER_CLOCK /
					CONFIG_SYS_HZ)) - now;
	}
	lastdec = now;

	return timestamp;
}

/* waits specified delay value and resets timestamp */
void udelay_masked (unsigned long usec)
{
	ulong tmo;
	ulong endtime;
	signed long diff;

	if (usec >= 1000) {		/* if "big" number, spread normalization to seconds */
		tmo = usec / 1000;	/* start to normalize for usec to ticks per sec */
		tmo *= CONFIG_SYS_HZ;		/* find number of "ticks" to wait to achieve target */
		tmo /= 1000;		/* finish normalize. */
	} else {			/* else small number, don't kill it prior to HZ multiply */
		tmo = usec * CONFIG_SYS_HZ;
		tmo /= (1000*1000);
	}

	endtime = get_timer_masked () + tmo;

	do {
		ulong now = get_timer_masked ();
		diff = endtime - now;
	} while (diff >= 0);
}

/*
 * This function is derived from PowerPC code (read timebase as long long).
 * On ARM it just returns the timer value.
 */
unsigned long long get_ticks(void)
{
	return get_timer(0);
}

/*
 * This function is derived from PowerPC code (timebase clock frequency).
 * On ARM it returns the number of timer ticks per second.
 */
ulong get_tbclk (void)
{
	return CONFIG_SYS_HZ;
}
Commit	Line	Data
ff7fefe6 WD	1	/*
	2	* (C) Copyright 2003
	3	* Texas Instruments <www.ti.com>
	4	*
	5	* (C) Copyright 2002
	6	* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
	7	* Marius Groeger <mgroeger@sysgo.de>
	8	*
	9	* (C) Copyright 2002
	10	* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
	11	* Alex Zuepke <azu@sysgo.de>
	12	*
	13	* (C) Copyright 2002-2004
792a09eb	14	* Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
ff7fefe6 WD	15	*
	16	* (C) Copyright 2004
	17	* Philippe Robin, ARM Ltd. <philippe.robin@arm.com>
	18	*
3765b3e7	19	* SPDX-License-Identifier: GPL-2.0+
ff7fefe6 WD	20	*/
	21
	22	#include <common.h>
eef6da03	23	#include <asm/io.h>
ff7fefe6	24
eef6da03 JH	25	#define TIMER_CLOCK (CONFIG_SYS_CLK_FREQ / (2 << CONFIG_SYS_PTV))
eef6da03 JH	26	#define TIMER_LOAD_VAL 0xffffffff
ff7fefe6 WD	27
ff7fefe6 WD	28	/* macro to read the 32 bit timer */
eef6da03 JH	29	#define READ_TIMER readl(CONFIG_SYS_TIMERBASE+8) \
eef6da03 JH	30	/ (TIMER_CLOCK / CONFIG_SYS_HZ)
ff7fefe6	31
c9ac3ba1 HS	32	DECLARE_GLOBAL_DATA_PTR;
c9ac3ba1 HS	33
66ee6923	34	#define timestamp gd->arch.tbl
582601da	35	#define lastdec gd->arch.lastinc
ff7fefe6 WD	36
	37	int timer_init (void)
	38	{
	39	int32_t val;
	40
	41	/* Start the decrementer ticking down from 0xffffffff */
6d0f6bcf	42	((int32_t ) (CONFIG_SYS_TIMERBASE + LOAD_TIM)) = TIMER_LOAD_VAL;
81472d89	43	val = MPUTIM_ST \| MPUTIM_AR \| MPUTIM_CLOCK_ENABLE \| (CONFIG_SYS_PTV << MPUTIM_PTV_BIT);
6d0f6bcf	44	((int32_t ) (CONFIG_SYS_TIMERBASE + CNTL_TIMER)) = val;
ff7fefe6 WD	45
	46	/* init the timestamp and lastdec value */
	47	reset_timer_masked();
	48
	49	return 0;
	50	}
	51
	52	/*
	53	* timer without interrupts
	54	*/
ff7fefe6 WD	55	ulong get_timer (ulong base)
	56	{
	57	return get_timer_masked () - base;
	58	}
	59
92381c41	60	/* delay x useconds AND preserve advance timestamp value */
3eb90bad	61	void __udelay (unsigned long usec)
ff7fefe6 WD	62	{
	63	ulong tmo, tmp;
	64
	65	if(usec >= 1000){ /* if "big" number, spread normalization to seconds */
	66	tmo = usec / 1000; /* start to normalize for usec to ticks per sec */
92381c41	67	tmo = CONFIG_SYS_HZ; / find number of "ticks" to wait to achieve target */
ff7fefe6 WD	68	tmo /= 1000; /* finish normalize. */
ff7fefe6 WD	69	}else{ /* else small number, don't kill it prior to HZ multiply */
6d0f6bcf	70	tmo = usec * CONFIG_SYS_HZ;
ff7fefe6 WD	71	tmo /= (1000*1000);
	72	}
	73
	74	tmp = get_timer (0); /* get current timestamp */
	75	if( (tmo + tmp + 1) < tmp ) /* if setting this fordward will roll time stamp */
	76	reset_timer_masked (); /* reset "advancing" timestamp to 0, set lastdec value */
	77	else
	78	tmo += tmp; /* else, set advancing stamp wake up time */
	79
	80	while (get_timer_masked () < tmo)/* loop till event */
	81	/NOP/;
	82	}
	83
	84	void reset_timer_masked (void)
	85	{
	86	/* reset time */
	87	lastdec = READ_TIMER; /* capure current decrementer value time */
	88	timestamp = 0; /* start "advancing" time stamp from 0 */
	89	}
	90
	91	ulong get_timer_masked (void)
	92	{
	93	ulong now = READ_TIMER; /* current tick value */
	94
	95	if (lastdec >= now) { /* normal mode (non roll) */
	96	/* normal mode */
	97	timestamp += lastdec - now; /* move stamp fordward with absoulte diff ticks */
	98	} else { /* we have overflow of the count down timer */
	99	/* nts = ts + ld + (TLV - now)
	100	* ts=old stamp, ld=time that passed before passing through -1
	101	* (TLV-now) amount of time after passing though -1
	102	* nts = new "advancing time stamp"...it could also roll and cause problems.
	103	*/
eef6da03 JH	104	timestamp += lastdec + (TIMER_LOAD_VAL / (TIMER_CLOCK /
eef6da03 JH	105	CONFIG_SYS_HZ)) - now;
ff7fefe6 WD	106	}
	107	lastdec = now;
	108
	109	return timestamp;
	110	}
	111
	112	/* waits specified delay value and resets timestamp */
	113	void udelay_masked (unsigned long usec)
	114	{
	115	ulong tmo;
	116	ulong endtime;
	117	signed long diff;
	118
	119	if (usec >= 1000) { /* if "big" number, spread normalization to seconds */
	120	tmo = usec / 1000; /* start to normalize for usec to ticks per sec */
6d0f6bcf	121	tmo = CONFIG_SYS_HZ; / find number of "ticks" to wait to achieve target */
ff7fefe6 WD	122	tmo /= 1000; /* finish normalize. */
ff7fefe6 WD	123	} else { /* else small number, don't kill it prior to HZ multiply */
6d0f6bcf	124	tmo = usec * CONFIG_SYS_HZ;
ff7fefe6 WD	125	tmo /= (1000*1000);
	126	}
	127
	128	endtime = get_timer_masked () + tmo;
	129
	130	do {
	131	ulong now = get_timer_masked ();
	132	diff = endtime - now;
	133	} while (diff >= 0);
	134	}
	135
	136	/*
	137	* This function is derived from PowerPC code (read timebase as long long).
	138	* On ARM it just returns the timer value.
	139	*/
	140	unsigned long long get_ticks(void)
	141	{
	142	return get_timer(0);
	143	}
	144
	145	/*
	146	* This function is derived from PowerPC code (timebase clock frequency).
	147	* On ARM it returns the number of timer ticks per second.
	148	*/
	149	ulong get_tbclk (void)
	150	{
eef6da03	151	return CONFIG_SYS_HZ;
ff7fefe6	152	}