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/*
* (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);
}
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