1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2015 Rockchip Electronics Co., Ltd
4  */
5 
6 #include <common.h>
7 #include <asm/arch/timer.h>
8 #include <asm/io.h>
9 #include <linux/types.h>
10 
11 struct rk_timer * const timer_ptr = (void *)CONFIG_SYS_TIMER_BASE;
12 
13 static uint64_t rockchip_get_ticks(void)
14 {
15 	uint64_t timebase_h, timebase_l;
16 
17 	timebase_l = readl(&timer_ptr->timer_curr_value0);
18 	timebase_h = readl(&timer_ptr->timer_curr_value1);
19 
20 	return timebase_h << 32 | timebase_l;
21 }
22 
23 static uint64_t usec_to_tick(unsigned int usec)
24 {
25 	uint64_t tick = usec;
26 	tick *= CONFIG_SYS_TIMER_RATE / (1000 * 1000);
27 	return tick;
28 }
29 
30 void rockchip_udelay(unsigned int usec)
31 {
32 	uint64_t tmp;
33 
34 	/* get timestamp */
35 	tmp = rockchip_get_ticks() + usec_to_tick(usec);
36 
37 	/* loop till event */
38 	while (rockchip_get_ticks() < tmp+1)
39 		;
40 }
41 
42 void rockchip_timer_init(void)
43 {
44 	writel(0xffffffff, &timer_ptr->timer_load_count0);
45 	writel(0xffffffff, &timer_ptr->timer_load_count1);
46 	writel(1, &timer_ptr->timer_ctrl_reg);
47 }
48