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// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2007-2011
* Allwinner Technology Co., Ltd. <www.allwinnertech.com>
* Tom Cubie <tangliang@allwinnertech.com>
*/
#include <common.h>
#include <init.h>
#include <time.h>
#include <asm/io.h>
#include <asm/arch/timer.h>
#include <linux/delay.h>
DECLARE_GLOBAL_DATA_PTR;
#define TIMER_MODE (0x0 << 7) /* continuous mode */
#define TIMER_DIV (0x0 << 4) /* pre scale 1 */
#define TIMER_SRC (0x1 << 2) /* osc24m */
#define TIMER_RELOAD (0x1 << 1) /* reload internal value */
#define TIMER_EN (0x1 << 0) /* enable timer */
#define TIMER_CLOCK (24 * 1000 * 1000)
#define COUNT_TO_USEC(x) ((x) / 24)
#define USEC_TO_COUNT(x) ((x) * 24)
#define TICKS_PER_HZ (TIMER_CLOCK / CONFIG_SYS_HZ)
#define TICKS_TO_HZ(x) ((x) / TICKS_PER_HZ)
#define TIMER_LOAD_VAL 0xffffffff
#define TIMER_NUM 0 /* we use timer 0 */
/* read the 32-bit timer */
static ulong read_timer(void)
{
struct sunxi_timer_reg *timers =
(struct sunxi_timer_reg *)SUNXI_TIMER_BASE;
struct sunxi_timer *timer = &timers->timer[TIMER_NUM];
/*
* The hardware timer counts down, therefore we invert to
* produce an incrementing timer.
*/
return ~readl(&timer->val);
}
/* init timer register */
int timer_init(void)
{
struct sunxi_timer_reg *timers =
(struct sunxi_timer_reg *)SUNXI_TIMER_BASE;
struct sunxi_timer *timer = &timers->timer[TIMER_NUM];
writel(TIMER_LOAD_VAL, &timer->inter);
writel(TIMER_MODE | TIMER_DIV | TIMER_SRC | TIMER_RELOAD | TIMER_EN,
&timer->ctl);
return 0;
}
/* timer without interrupts */
static ulong get_timer_masked(void)
{
/* current tick value */
ulong now = TICKS_TO_HZ(read_timer());
if (now >= gd->arch.lastinc) /* normal (non rollover) */
gd->arch.tbl += (now - gd->arch.lastinc);
else {
/* rollover */
gd->arch.tbl += (TICKS_TO_HZ(TIMER_LOAD_VAL)
- gd->arch.lastinc) + now;
}
gd->arch.lastinc = now;
return gd->arch.tbl;
}
ulong get_timer(ulong base)
{
return get_timer_masked() - base;
}
/* delay x useconds */
void __udelay(unsigned long usec)
{
long tmo = USEC_TO_COUNT(usec);
ulong now, last = read_timer();
while (tmo > 0) {
now = read_timer();
if (now > last) /* normal (non rollover) */
tmo -= now - last;
else /* rollover */
tmo -= TIMER_LOAD_VAL - last + now;
last = now;
}
}
/*
* 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;
}
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