u-boot/arch/arm/cpu/armv7/sunxi/timer.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

112 lines
2.6 KiB
C

// 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 <asm/io.h>
#include <asm/arch/timer.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 */
ulong get_timer(ulong base)
{
return get_timer_masked() - base;
}
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;
}
/* 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;
}