[J-u-boot.git] / cpu / arm946es / interrupts.c

/*
 * (C) Copyright 2003
 * Texas Instruments <www.ti.com>
 *
 * (C) Copyright 2002
 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Marius Groeger <[email protected]>
 *
 * (C) Copyright 2002
 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Alex Zuepke <[email protected]>
 *
 * (C) Copyright 2002-2004
 * Gary Jennejohn, DENX Software Engineering, <[email protected]>
 *
 * (C) Copyright 2004
 * Philippe Robin, ARM Ltd. <[email protected]>
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */

#include <common.h>
#include <arm946es.h>

#define TIMER_LOAD_VAL 0xffffffff
extern void reset_cpu(ulong addr);

#ifdef CONFIG_INTEGRATOR
	/* Timer functionality supplied by Integrator board (AP or CP) */
#else

static ulong timestamp;
static ulong lastdec;

/* nothing really to do with interrupts, just starts up a counter. */
int interrupt_init (void)
{
	/* init the timestamp and lastdec value */
	reset_timer_masked();

	return (0);
}

/*
 * timer without interrupts
 */

void reset_timer (void)
{
	reset_timer_masked ();
}

ulong get_timer (ulong base)
{
	return get_timer_masked () - base;
}

void set_timer (ulong t)
{
	timestamp = t;
}

/* delay x useconds AND perserve advance timstamp value */
void udelay(unsigned long usec)
{
	udelay_masked(usec);
}

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_raw (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 - now;
	}
	lastdec = now;

	return timestamp;
}

ulong get_timer_masked (void)
{
	return get_timer_raw() / TIMER_LOAD_VAL;
}

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

	if(usec >= 1000){               /* if "big" number, spread normalization to seconds */
		tmo = usec / 1000;      /* start to normalize for usec to ticks per sec */
		tmo *= CFG_HZ_CLOCK;    /* 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 * CFG_HZ_CLOCK;
		tmo /= (1000*1000);
	}

	reset_timer_masked ();	/* set "advancing" timestamp to 0, set lastdec vaule */

	while (get_timer_raw () < tmo) /* wait for time stamp to overtake tick number.*/
		/*NOP*/;
}

/*
 * 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)
{
	ulong tbclk;

	tbclk = CFG_HZ;
	return tbclk;
}

#endif /* CONFIG_INTEGRATOR */
Commit	Line	Data
74f4304e 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 <[email protected]>
	8	*
	9	* (C) Copyright 2002
	10	* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
	11	* Alex Zuepke <[email protected]>
	12	*
	13	* (C) Copyright 2002-2004
	14	* Gary Jennejohn, DENX Software Engineering, <[email protected]>
	15	*
	16	* (C) Copyright 2004
	17	* Philippe Robin, ARM Ltd. <[email protected]>
	18	*
	19	* See file CREDITS for list of people who contributed to this
	20	* project.
	21	*
	22	* This program is free software; you can redistribute it and/or
	23	* modify it under the terms of the GNU General Public License as
	24	* published by the Free Software Foundation; either version 2 of
	25	* the License, or (at your option) any later version.
	26	*
	27	* This program is distributed in the hope that it will be useful,
	28	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	29	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	30	* GNU General Public License for more details.
	31	*
	32	* You should have received a copy of the GNU General Public License
	33	* along with this program; if not, write to the Free Software
	34	* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
	35	* MA 02111-1307 USA
	36	*/
	37
	38	#include <common.h>
	39	#include <arm946es.h>
74f4304e WD	40
	41	#define TIMER_LOAD_VAL 0xffffffff
	42	extern void reset_cpu(ulong addr);
	43
74f4304e WD	44	#ifdef CONFIG_INTEGRATOR
	45	/* Timer functionality supplied by Integrator board (AP or CP) */
	46	#else
	47
	48	static ulong timestamp;
	49	static ulong lastdec;
	50
	51	/* nothing really to do with interrupts, just starts up a counter. */
	52	int interrupt_init (void)
	53	{
	54	/* init the timestamp and lastdec value */
	55	reset_timer_masked();
	56
	57	return (0);
	58	}
	59
	60	/*
	61	* timer without interrupts
	62	*/
	63
	64	void reset_timer (void)
	65	{
	66	reset_timer_masked ();
	67	}
	68
	69	ulong get_timer (ulong base)
	70	{
	71	return get_timer_masked () - base;
	72	}
	73
	74	void set_timer (ulong t)
	75	{
	76	timestamp = t;
	77	}
	78
	79	/* delay x useconds AND perserve advance timstamp value */
	80	void udelay(unsigned long usec)
	81	{
	82	udelay_masked(usec);
	83	}
	84
	85	void reset_timer_masked (void)
	86	{
	87	/* reset time */
	88	lastdec = READ_TIMER; /* capure current decrementer value time */
	89	timestamp = 0; /* start "advancing" time stamp from 0 */
	90	}
	91
	92	ulong get_timer_raw (void)
	93	{
	94	ulong now = READ_TIMER; /* current tick value */
	95
	96	if (lastdec >= now) { /* normal mode (non roll) */
	97	/* normal mode */
	98	timestamp += lastdec - now; /* move stamp fordward with absoulte diff ticks */
	99	} else { /* we have overflow of the count down timer */
	100	/* nts = ts + ld + (TLV - now)
	101	* ts=old stamp, ld=time that passed before passing through -1
	102	* (TLV-now) amount of time after passing though -1
	103	* nts = new "advancing time stamp"...it could also roll and cause problems.
	104	*/
	105	timestamp += lastdec + TIMER_LOAD_VAL - now;
	106	}
	107	lastdec = now;
108
109	return timestamp;
110	}
111
112	ulong get_timer_masked (void)
113	{
114	return get_timer_raw() / TIMER_LOAD_VAL;
115	}
116
117	/* waits specified delay value and resets timestamp */
118	void udelay_masked (unsigned long usec)
119	{
120	ulong tmo;
121
122	if(usec >= 1000){ /* if "big" number, spread normalization to seconds */
123	tmo = usec / 1000; /* start to normalize for usec to ticks per sec */
124	tmo = CFG_HZ_CLOCK; / find number of "ticks" to wait to achieve target */
125	tmo /= 1000; /* finish normalize. */
126	}else{ /* else small number, don't kill it prior to HZ multiply */
127	tmo = usec * CFG_HZ_CLOCK;
128	tmo /= (1000*1000);
129	}
130
131	reset_timer_masked (); /* set "advancing" timestamp to 0, set lastdec vaule */
132
133	while (get_timer_raw () < tmo) /* wait for time stamp to overtake tick number.*/
134	/NOP/;
135	}
136
137	/*
138	* This function is derived from PowerPC code (read timebase as long long).
139	* On ARM it just returns the timer value.
140	*/
141	unsigned long long get_ticks(void)
142	{
143	return get_timer(0);
144	}
145
146	/*
147	* This function is derived from PowerPC code (timebase clock frequency).
148	* On ARM it returns the number of timer ticks per second.
149	*/
150	ulong get_tbclk (void)
151	{
152	ulong tbclk;
153
154	tbclk = CFG_HZ;
155	return tbclk;
156	}
157
158	#endif /* CONFIG_INTEGRATOR */