mirror of
https://github.com/u-boot/u-boot.git
synced 2024-11-29 07:33:29 +08:00
1045315df0
This function belongs in time.h so move it over and add a comment. Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Tom Rini <trini@konsulko.com>
164 lines
3.7 KiB
C
164 lines
3.7 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* (C) Copyright 2002
|
|
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
|
|
* Marius Groeger <mgroeger@sysgo.de>
|
|
*
|
|
* (C) Copyright 2002
|
|
* David Mueller, ELSOFT AG, <d.mueller@elsoft.ch>
|
|
*
|
|
* (C) Copyright 2003
|
|
* Texas Instruments, <www.ti.com>
|
|
* Kshitij Gupta <Kshitij@ti.com>
|
|
*
|
|
* (C) Copyright 2004
|
|
* ARM Ltd.
|
|
* Philippe Robin, <philippe.robin@arm.com>
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <div64.h>
|
|
#include <time.h>
|
|
|
|
#ifdef CONFIG_ARCH_CINTEGRATOR
|
|
#define DIV_CLOCK_INIT 1
|
|
#define TIMER_LOAD_VAL 0xFFFFFFFFL
|
|
#else
|
|
#define DIV_CLOCK_INIT 256
|
|
#define TIMER_LOAD_VAL 0x0000FFFFL
|
|
#endif
|
|
/* The Integrator/CP timer1 is clocked at 1MHz
|
|
* can be divided by 16 or 256
|
|
* and can be set up as a 32-bit timer
|
|
*/
|
|
/* U-Boot expects a 32 bit timer, running at CONFIG_SYS_HZ */
|
|
/* Keep total timer count to avoid losing decrements < div_timer */
|
|
static unsigned long long total_count = 0;
|
|
static unsigned long long lastdec; /* Timer reading at last call */
|
|
/* Divisor applied to timer clock */
|
|
static unsigned long long div_clock = DIV_CLOCK_INIT;
|
|
static unsigned long long div_timer = 1; /* Divisor to convert timer reading
|
|
* change to U-Boot ticks
|
|
*/
|
|
/* CONFIG_SYS_HZ = CONFIG_SYS_HZ_CLOCK/(div_clock * div_timer) */
|
|
static ulong timestamp; /* U-Boot ticks since startup */
|
|
|
|
#define READ_TIMER (*(volatile ulong *)(CONFIG_SYS_TIMERBASE+4))
|
|
|
|
/* all function return values in U-Boot ticks i.e. (1/CONFIG_SYS_HZ) sec
|
|
* - unless otherwise stated
|
|
*/
|
|
|
|
/* starts up a counter
|
|
* - the Integrator/CP timer can be set up to issue an interrupt */
|
|
int timer_init (void)
|
|
{
|
|
/* Load timer with initial value */
|
|
*(volatile ulong *)(CONFIG_SYS_TIMERBASE + 0) = TIMER_LOAD_VAL;
|
|
#ifdef CONFIG_ARCH_CINTEGRATOR
|
|
/* Set timer to be
|
|
* enabled 1
|
|
* periodic 1
|
|
* no interrupts 0
|
|
* X 0
|
|
* divider 1 00 == less rounding error
|
|
* 32 bit 1
|
|
* wrapping 0
|
|
*/
|
|
*(volatile ulong *)(CONFIG_SYS_TIMERBASE + 8) = 0x000000C2;
|
|
#else
|
|
/* Set timer to be
|
|
* enabled 1
|
|
* free-running 0
|
|
* XX 00
|
|
* divider 256 10
|
|
* XX 00
|
|
*/
|
|
*(volatile ulong *)(CONFIG_SYS_TIMERBASE + 8) = 0x00000088;
|
|
#endif
|
|
|
|
/* init the timestamp */
|
|
total_count = 0ULL;
|
|
/* capure current decrementer value */
|
|
lastdec = READ_TIMER;
|
|
/* start "advancing" time stamp from 0 */
|
|
timestamp = 0L;
|
|
|
|
div_timer = CONFIG_SYS_HZ_CLOCK;
|
|
do_div(div_timer, CONFIG_SYS_HZ);
|
|
do_div(div_timer, div_clock);
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* timer without interrupts
|
|
*/
|
|
|
|
/* converts the timer reading to U-Boot ticks */
|
|
/* the timestamp is the number of ticks since reset */
|
|
static ulong get_timer_masked (void)
|
|
{
|
|
/* get current count */
|
|
unsigned long long now = READ_TIMER;
|
|
|
|
if(now > lastdec) {
|
|
/* Must have wrapped */
|
|
total_count += lastdec + TIMER_LOAD_VAL + 1 - now;
|
|
} else {
|
|
total_count += lastdec - now;
|
|
}
|
|
lastdec = now;
|
|
|
|
/* Reuse "now" */
|
|
now = total_count;
|
|
do_div(now, div_timer);
|
|
timestamp = now;
|
|
|
|
return timestamp;
|
|
}
|
|
|
|
ulong get_timer (ulong base_ticks)
|
|
{
|
|
return get_timer_masked () - base_ticks;
|
|
}
|
|
|
|
/* delay usec useconds */
|
|
void __udelay (unsigned long usec)
|
|
{
|
|
ulong tmo, tmp;
|
|
|
|
/* Convert to U-Boot ticks */
|
|
tmo = usec * CONFIG_SYS_HZ;
|
|
tmo /= (1000000L);
|
|
|
|
tmp = get_timer_masked(); /* get current timestamp */
|
|
tmo += tmp; /* form target timestamp */
|
|
|
|
while (get_timer_masked () < tmo) {/* loop till event */
|
|
/*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);
|
|
}
|
|
|
|
/*
|
|
* Return the timebase clock frequency
|
|
* i.e. how often the timer decrements
|
|
*/
|
|
ulong get_tbclk (void)
|
|
{
|
|
unsigned long long tmp = CONFIG_SYS_HZ_CLOCK;
|
|
|
|
do_div(tmp, div_clock);
|
|
|
|
return tmp;
|
|
}
|