timer.c

来自「bootloader源代码」· C语言 代码 · 共 54 行

/*****************************************
 Copyright (c) 2001-2002 
 Sigma Designs, Inc. All Rights Reserved
 Proprietary and Confidential
 *****************************************/

/* This file is part of the boot loader */

/*
 * timer.c
 *
 * timer for ARM
 */

#include "util.h"
#include "uart.h"
#include "jasper.h"
#include "jasper_const.h"
#include "io.h"

static int g_ticks = 0;
static unsigned int g_last = 0;

void timer_init(void)
{
	__raw_writel(0xffff, JASPER_TIMER_BASE + TIMER_TMR0LOAD);
	__raw_writel(0xc8, JASPER_TIMER_BASE + TIMER_TMR0CTL);
}

unsigned int timer_getticks(void)
{
	unsigned int timerval = __raw_readl(JASPER_TIMER_BASE + TIMER_TMR0VAL);
	
	if ((g_last & 0x8000) != (timerval & 0x8000))
		++g_ticks;
	g_last = timerval;

	return g_ticks;
}

int timer_timeout(unsigned int startticks, int timeout)
{
	unsigned int ticks = timer_getticks();
	
	if (timeout == 0)
		return 1;
	else if (timeout > 0) {
		if ((ticks - startticks) > (timeout >> 8))
			return 1;
	}

	return 0;
}