2 * Copyright (C) 2009 Samsung Electronics
3 * Heungjun Kim <riverful.kim@samsung.com>
4 * Inki Dae <inki.dae@samsung.com>
5 * Minkyu Kang <mk7.kang@samsung.com>
7 * SPDX-License-Identifier: GPL-2.0+
13 #include <asm/arch/pwm.h>
14 #include <asm/arch/clk.h>
17 DECLARE_GLOBAL_DATA_PTR;
19 unsigned long get_current_tick(void);
21 /* macro to read the 16 bit timer */
22 static inline struct s5p_timer *s5p_get_base_timer(void)
24 return (struct s5p_timer *)samsung_get_base_timer();
28 * Read the countdown timer.
30 * This operates at 1MHz and counts downwards. It will wrap about every
31 * hour (2^32 microseconds).
33 * @return current value of timer
35 static unsigned long timer_get_us_down(void)
37 struct s5p_timer *const timer = s5p_get_base_timer();
39 return readl(&timer->tcnto4);
45 pwm_init(4, MUX_DIV_4, 0);
46 pwm_config(4, 100000, 100000);
49 /* Use this as the current monotonic time in us */
50 gd->arch.timer_reset_value = 0;
52 /* Use this as the last timer value we saw */
53 gd->arch.lastinc = timer_get_us_down();
60 * timer without interrupts
62 unsigned long get_timer(unsigned long base)
64 unsigned long long time_ms;
66 ulong now = timer_get_us_down();
69 * Increment the time by the amount elapsed since the last read.
70 * The timer may have wrapped around, but it makes no difference to
71 * our arithmetic here.
73 gd->arch.timer_reset_value += gd->arch.lastinc - now;
74 gd->arch.lastinc = now;
76 /* Divide by 1000 to convert from us to ms */
77 time_ms = gd->arch.timer_reset_value;
78 do_div(time_ms, 1000);
79 return time_ms - base;
82 unsigned long __attribute__((no_instrument_function)) timer_get_us(void)
84 static unsigned long base_time_us;
86 struct s5p_timer *const timer =
87 (struct s5p_timer *)samsung_get_base_timer();
88 unsigned long now_downward_us = readl(&timer->tcnto4);
91 base_time_us = now_downward_us;
93 /* Note that this timer counts downward. */
94 return base_time_us - now_downward_us;
97 /* delay x useconds */
98 void __udelay(unsigned long usec)
100 unsigned long count_value;
102 count_value = timer_get_us_down();
103 while ((int)(count_value - timer_get_us_down()) < (int)usec)
107 void reset_timer_masked(void)
109 struct s5p_timer *const timer = s5p_get_base_timer();
112 gd->arch.lastinc = readl(&timer->tcnto4);
117 * This function is derived from PowerPC code (read timebase as long long).
118 * On ARM it just returns the timer value.
120 unsigned long long get_ticks(void)
126 * This function is derived from PowerPC code (timebase clock frequency).
127 * On ARM it returns the number of timer ticks per second.
129 unsigned long get_tbclk(void)
131 return CONFIG_SYS_HZ;