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/*
* (C) Copyright 2007
* Sascha Hauer, Pengutronix
*
* (C) Copyright 2009 Freescale Semiconductor, Inc.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/io.h>
#include <div64.h>
#include <asm/arch/imx-regs.h>
#include <asm/arch/clock.h>
/* General purpose timers registers */
struct mxc_gpt {
unsigned int control;
unsigned int prescaler;
unsigned int status;
unsigned int nouse[6];
unsigned int counter;
};
static struct mxc_gpt *cur_gpt = (struct mxc_gpt *)GPT1_BASE_ADDR;
/* General purpose timers bitfields */
#define GPTCR_SWR (1 << 15) /* Software reset */
#define GPTCR_FRR (1 << 9) /* Freerun / restart */
#define GPTCR_CLKSOURCE_32 (4 << 6) /* Clock source */
#define GPTCR_TEN 1 /* Timer enable */
DECLARE_GLOBAL_DATA_PTR;
static inline unsigned long long tick_to_time(unsigned long long tick)
{
tick *= CONFIG_SYS_HZ;
do_div(tick, MXC_CLK32);
return tick;
}
static inline unsigned long long us_to_tick(unsigned long long usec)
{
usec = usec * MXC_CLK32 + 999999;
do_div(usec, 1000000);
return usec;
}
int timer_init(void)
{
int i;
/* setup GP Timer 1 */
__raw_writel(GPTCR_SWR, &cur_gpt->control);
/* We have no udelay by now */
for (i = 0; i < 100; i++)
__raw_writel(0, &cur_gpt->control);
__raw_writel(0, &cur_gpt->prescaler); /* 32Khz */
/* Freerun Mode, PERCLK1 input */
i = __raw_readl(&cur_gpt->control);
__raw_writel(i | GPTCR_CLKSOURCE_32 | GPTCR_TEN, &cur_gpt->control);
gd->arch.tbl = __raw_readl(&cur_gpt->counter);
gd->arch.tbu = 0;
return 0;
}
unsigned long long get_ticks(void)
{
ulong now = __raw_readl(&cur_gpt->counter); /* current tick value */
/* increment tbu if tbl has rolled over */
if (now < gd->arch.tbl)
gd->arch.tbu++;
gd->arch.tbl = now;
return (((unsigned long long)gd->arch.tbu) << 32) | gd->arch.tbl;
}
ulong get_timer_masked(void)
{
/*
* get_ticks() returns a long long (64 bit), it wraps in
* 2^64 / MXC_CLK32 = 2^64 / 2^15 = 2^49 ~ 5 * 10^14 (s) ~
* 5 * 10^9 days... and get_ticks() * CONFIG_SYS_HZ wraps in
* 5 * 10^6 days - long enough.
*/
return tick_to_time(get_ticks());
}
ulong get_timer(ulong base)
{
return get_timer_masked() - base;
}
/* delay x useconds AND preserve advance timstamp value */
void __udelay(unsigned long usec)
{
unsigned long long tmp;
ulong tmo;
tmo = us_to_tick(usec);
tmp = get_ticks() + tmo; /* get current timestamp */
while (get_ticks() < tmp) /* loop till event */
/*NOP*/;
}
/*
* 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 MXC_CLK32;
}
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