[people/ms/u-boot.git] / cpu / arm925t / interrupts.c

/*
 * (C) Copyright 2009
 * 2N Telekomunikace, <www.2n.cz>
 *
 * (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
 * Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
 *
 * 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 <arm925t.h>
#include <configs/omap1510.h>
#include <asm/io.h>

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

static uint32_t timestamp;
static uint32_t lastdec;

/* nothing really to do with interrupts, just starts up a counter. */
int interrupt_init (void)
{
	/* Start the decrementer ticking down from 0xffffffff */
	__raw_writel(TIMER_LOAD_VAL, CONFIG_SYS_TIMERBASE + LOAD_TIM);
	__raw_writel(MPUTIM_ST | MPUTIM_AR | MPUTIM_CLOCK_ENABLE |
		(CONFIG_SYS_PTV << MPUTIM_PTV_BIT),
		CONFIG_SYS_TIMERBASE + CNTL_TIMER);

	/* 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 preserve advance timestamp value */
void udelay (unsigned long usec)
{
	int32_t tmo = usec * (TIMER_CLOCK / 1000) / 1000;
	uint32_t now, last = __raw_readl(CONFIG_SYS_TIMERBASE + READ_TIM);

	while (tmo > 0) {
		now = __raw_readl(CONFIG_SYS_TIMERBASE + READ_TIM);
		if (last < now) /* count down timer underflow */
			tmo -= TIMER_LOAD_VAL - now + last;
		else
			tmo -= last - now;
		last = now;
	}
}

void reset_timer_masked (void)
{
	/* reset time */
	lastdec = __raw_readl(CONFIG_SYS_TIMERBASE + READ_TIM) /
			(TIMER_CLOCK / CONFIG_SYS_HZ);
	timestamp = 0;	       /* start "advancing" time stamp from 0 */
}

ulong get_timer_masked (void)
{
	uint32_t now = __raw_readl(CONFIG_SYS_TIMERBASE + READ_TIM) /
			(TIMER_CLOCK / CONFIG_SYS_HZ);
	if (lastdec < now)	/* count down timer underflow */
		timestamp += TIMER_LOAD_VAL / (TIMER_CLOCK / CONFIG_SYS_HZ) -
				now + lastdec;
	else
		timestamp += lastdec - now;
	lastdec = now;

	return timestamp;
}

/*
 * 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
2e5983d2	1	/*
3791a118 LM	2	* (C) Copyright 2009
	3	* 2N Telekomunikace, <www.2n.cz>
	4	*
2e5983d2 WD	5	* (C) Copyright 2003
	6	* Texas Instruments, <www.ti.com>
	7	*
	8	* (C) Copyright 2002
	9	* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
	10	* Marius Groeger <mgroeger@sysgo.de>
	11	*
	12	* (C) Copyright 2002
	13	* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
	14	* Alex Zuepke <azu@sysgo.de>
	15	*
	16	* (C) Copyright 2002
792a09eb	17	* Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
2e5983d2 WD	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
232c150a	29	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
2e5983d2 WD	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 <arm925t.h>
	40	#include <configs/omap1510.h>
89c00fb1	41	#include <asm/io.h>
2e5983d2	42
3791a118 LM	43	#define TIMER_LOAD_VAL 0xffffffff
3791a118 LM	44	#define TIMER_CLOCK (CONFIG_SYS_CLK_FREQ / (2 << CONFIG_SYS_PTV))
2e5983d2	45
89c00fb1 LM	46	static uint32_t timestamp;
89c00fb1 LM	47	static uint32_t lastdec;
2e5983d2 WD	48
	49	/* nothing really to do with interrupts, just starts up a counter. */
	50	int interrupt_init (void)
	51	{
a3ad8e26	52	/* Start the decrementer ticking down from 0xffffffff */
89c00fb1 LM	53	__raw_writel(TIMER_LOAD_VAL, CONFIG_SYS_TIMERBASE + LOAD_TIM);
	54	__raw_writel(MPUTIM_ST \| MPUTIM_AR \| MPUTIM_CLOCK_ENABLE \|
	55	(CONFIG_SYS_PTV << MPUTIM_PTV_BIT),
	56	CONFIG_SYS_TIMERBASE + CNTL_TIMER);
a3ad8e26 WD	57
	58	/* init the timestamp and lastdec value */
	59	reset_timer_masked();
	60
fe672d60	61	return 0;
2e5983d2 WD	62	}
	63
	64	/*
	65	* timer without interrupts
	66	*/
	67
	68	void reset_timer (void)
	69	{
	70	reset_timer_masked ();
	71	}
	72
	73	ulong get_timer (ulong base)
	74	{
	75	return get_timer_masked () - base;
	76	}
	77
	78	void set_timer (ulong t)
	79	{
	80	timestamp = t;
	81	}
	82
0b8fa03b	83	/* delay x useconds AND preserve advance timestamp value */
2e5983d2 WD	84	void udelay (unsigned long usec)
2e5983d2 WD	85	{
3791a118 LM	86	int32_t tmo = usec * (TIMER_CLOCK / 1000) / 1000;
	87	uint32_t now, last = __raw_readl(CONFIG_SYS_TIMERBASE + READ_TIM);
	88
	89	while (tmo > 0) {
	90	now = __raw_readl(CONFIG_SYS_TIMERBASE + READ_TIM);
	91	if (last < now) /* count down timer underflow */
	92	tmo -= TIMER_LOAD_VAL - now + last;
	93	else
	94	tmo -= last - now;
	95	last = now;
a3ad8e26	96	}
2e5983d2 WD	97	}
	98
	99	void reset_timer_masked (void)
	100	{
	101	/* reset time */
3791a118 LM	102	lastdec = __raw_readl(CONFIG_SYS_TIMERBASE + READ_TIM) /
3791a118 LM	103	(TIMER_CLOCK / CONFIG_SYS_HZ);
232c150a	104	timestamp = 0; /* start "advancing" time stamp from 0 */
2e5983d2 WD	105	}
	106
	107	ulong get_timer_masked (void)
	108	{
3791a118 LM	109	uint32_t now = __raw_readl(CONFIG_SYS_TIMERBASE + READ_TIM) /
	110	(TIMER_CLOCK / CONFIG_SYS_HZ);
	111	if (lastdec < now) /* count down timer underflow */
	112	timestamp += TIMER_LOAD_VAL / (TIMER_CLOCK / CONFIG_SYS_HZ) -
	113	now + lastdec;
	114	else
	115	timestamp += lastdec - now;
2e5983d2 WD	116	lastdec = now;
	117
	118	return timestamp;
	119	}
	120
2e5983d2 WD	121	/*
	122	* This function is derived from PowerPC code (read timebase as long long).
	123	* On ARM it just returns the timer value.
	124	*/
	125	unsigned long long get_ticks(void)
	126	{
	127	return get_timer(0);
	128	}
	129
	130	/*
	131	* This function is derived from PowerPC code (timebase clock frequency).
	132	* On ARM it returns the number of timer ticks per second.
	133	*/
	134	ulong get_tbclk (void)
a3ad8e26	135	{
fe672d60	136	return CONFIG_SYS_HZ;
2e5983d2	137	}