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// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2014 Freescale Semiconductor, Inc.
*/
#include <init.h>
#include <time.h>
#include <asm/global_data.h>
#include <asm/io.h>
#include <div64.h>
#include <asm/arch/immap_ls102xa.h>
#include <asm/arch/clock.h>
#include <linux/delay.h>
DECLARE_GLOBAL_DATA_PTR;
/*
* This function is intended for SHORT delays only.
* It will overflow at around 10 seconds @ 400MHz,
* or 20 seconds @ 200MHz.
*/
unsigned long usec2ticks(unsigned long usec)
{
ulong ticks;
if (usec < 1000)
ticks = ((usec * (get_tbclk()/1000)) + 500) / 1000;
else
ticks = ((usec / 10) * (get_tbclk() / 100000));
return ticks;
}
static inline unsigned long long tick_to_time(unsigned long long tick)
{
unsigned long freq;
asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (freq));
tick *= CONFIG_SYS_HZ;
do_div(tick, freq);
return tick;
}
static inline unsigned long long us_to_tick(unsigned long long usec)
{
unsigned long freq;
asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (freq));
usec = usec * freq + 999999;
do_div(usec, 1000000);
return usec;
}
int timer_init(void)
{
struct sctr_regs *sctr = (struct sctr_regs *)SCTR_BASE_ADDR;
unsigned long ctrl, freq;
unsigned long long val;
/* Enable System Counter */
writel(SYS_COUNTER_CTRL_ENABLE, &sctr->cntcr);
freq = CONFIG_COUNTER_FREQUENCY;
asm("mcr p15, 0, %0, c14, c0, 0" : : "r" (freq));
/* Set PL1 Physical Timer Ctrl */
ctrl = ARCH_TIMER_CTRL_ENABLE;
asm("mcr p15, 0, %0, c14, c2, 1" : : "r" (ctrl));
/* Set PL1 Physical Comp Value */
val = TIMER_COMP_VAL;
asm("mcrr p15, 2, %Q0, %R0, c14" : : "r" (val));
gd->arch.tbl = 0;
gd->arch.tbu = 0;
return 0;
}
unsigned long long get_ticks(void)
{
unsigned long long now;
asm("mrrc p15, 0, %Q0, %R0, c14" : "=r" (now));
gd->arch.tbl = (unsigned long)(now & 0xffffffff);
gd->arch.tbu = (unsigned long)(now >> 32);
return now;
}
unsigned long get_timer(ulong base)
{
return tick_to_time(get_ticks()) - base;
}
/* delay x useconds and preserve advance timstamp value */
void __udelay(unsigned long usec)
{
unsigned long long start;
unsigned long tmo;
start = get_ticks(); /* get current timestamp */
tmo = us_to_tick(usec); /* convert usecs to ticks */
while ((get_ticks() - start) < tmo)
; /* loop till time has passed */
}
/*
* This function is derived from PowerPC code (timebase clock frequency).
* On ARM it returns the number of timer ticks per second.
*/
unsigned long get_tbclk(void)
{
unsigned long freq;
asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (freq));
return freq;
}
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