diff options
Diffstat (limited to 'arch/arm/cpu/tegra20-common/timer.c')
| -rw-r--r-- | arch/arm/cpu/tegra20-common/timer.c | 111 | 
1 files changed, 111 insertions, 0 deletions
| diff --git a/arch/arm/cpu/tegra20-common/timer.c b/arch/arm/cpu/tegra20-common/timer.c new file mode 100644 index 000000000..562e41401 --- /dev/null +++ b/arch/arm/cpu/tegra20-common/timer.c @@ -0,0 +1,111 @@ +/* + * (C) Copyright 2010,2011 + * NVIDIA Corporation <www.nvidia.com> + * + * (C) Copyright 2008 + * Texas Instruments + * + * Richard Woodruff <r-woodruff2@ti.com> + * Syed Moahmmed Khasim <khasim@ti.com> + * + * (C) Copyright 2002 + * Sysgo Real-Time Solutions, GmbH <www.elinos.com> + * Marius Groeger <mgroeger@sysgo.de> + * 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 <asm/io.h> +#include <asm/arch/tegra20.h> +#include <asm/arch/timer.h> + +DECLARE_GLOBAL_DATA_PTR; + +/* counter runs at 1MHz */ +#define TIMER_CLK	1000000 +#define TIMER_LOAD_VAL	0xffffffff + +/* timer without interrupts */ +ulong get_timer(ulong base) +{ +	return get_timer_masked() - base; +} + +/* delay x useconds */ +void __udelay(unsigned long usec) +{ +	long tmo = usec * (TIMER_CLK / 1000) / 1000; +	unsigned long now, last = timer_get_us(); + +	while (tmo > 0) { +		now = timer_get_us(); +		if (last > now) /* count up timer overflow */ +			tmo -= TIMER_LOAD_VAL - last + now; +		else +			tmo -= now - last; +		last = now; +	} +} + +ulong get_timer_masked(void) +{ +	ulong now; + +	/* current tick value */ +	now = timer_get_us() / (TIMER_CLK / CONFIG_SYS_HZ); + +	if (now >= gd->lastinc)	/* normal mode (non roll) */ +		/* move stamp forward with absolute diff ticks */ +		gd->tbl += (now - gd->lastinc); +	else	/* we have rollover of incrementer */ +		gd->tbl += ((TIMER_LOAD_VAL / (TIMER_CLK / CONFIG_SYS_HZ)) +				- gd->lastinc) + now; +	gd->lastinc = now; +	return gd->tbl; +} + +/* + * 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; +} + +unsigned long timer_get_us(void) +{ +	struct timerus *timer_base = (struct timerus *)NV_PA_TMRUS_BASE; + +	return readl(&timer_base->cntr_1us); +} |