blob: 8141f40d5c094b1755f1a0ec60f765f2c6046286 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
|
// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2009 Samsung Electronics
* Heungjun Kim <riverful.kim@samsung.com>
* Inki Dae <inki.dae@samsung.com>
* Minkyu Kang <mk7.kang@samsung.com>
*/
#include <common.h>
#include <div64.h>
#include <init.h>
#include <time.h>
#include <asm/global_data.h>
#include <asm/io.h>
#include <asm/arch/pwm.h>
#include <asm/arch/clk.h>
#include <linux/delay.h>
/* Use the old PWM interface for now */
#undef CONFIG_DM_PWM
#include <pwm.h>
DECLARE_GLOBAL_DATA_PTR;
unsigned long get_current_tick(void);
static void reset_timer_masked(void);
/* macro to read the 16 bit timer */
static inline struct s5p_timer *s5p_get_base_timer(void)
{
return (struct s5p_timer *)samsung_get_base_timer();
}
/**
* Read the countdown timer.
*
* This operates at 1MHz and counts downwards. It will wrap about every
* hour (2^32 microseconds).
*
* @return current value of timer
*/
static unsigned long timer_get_us_down(void)
{
struct s5p_timer *const timer = s5p_get_base_timer();
return readl(&timer->tcnto4);
}
int timer_init(void)
{
/* PWM Timer 4 */
pwm_init(4, MUX_DIV_4, 0);
pwm_config(4, 100000, 100000);
pwm_enable(4);
/* Use this as the current monotonic time in us */
gd->arch.timer_reset_value = 0;
/* Use this as the last timer value we saw */
gd->arch.lastinc = timer_get_us_down();
reset_timer_masked();
return 0;
}
/*
* timer without interrupts
*/
unsigned long get_timer(unsigned long base)
{
unsigned long long time_ms;
ulong now = timer_get_us_down();
/*
* Increment the time by the amount elapsed since the last read.
* The timer may have wrapped around, but it makes no difference to
* our arithmetic here.
*/
gd->arch.timer_reset_value += gd->arch.lastinc - now;
gd->arch.lastinc = now;
/* Divide by 1000 to convert from us to ms */
time_ms = gd->arch.timer_reset_value;
do_div(time_ms, 1000);
return time_ms - base;
}
unsigned long __attribute__((no_instrument_function)) timer_get_us(void)
{
static unsigned long base_time_us;
struct s5p_timer *const timer =
(struct s5p_timer *)samsung_get_base_timer();
unsigned long now_downward_us = readl(&timer->tcnto4);
if (!base_time_us)
base_time_us = now_downward_us;
/* Note that this timer counts downward. */
return base_time_us - now_downward_us;
}
/* delay x useconds */
void __udelay(unsigned long usec)
{
unsigned long count_value;
count_value = timer_get_us_down();
while ((int)(count_value - timer_get_us_down()) < (int)usec)
;
}
static void reset_timer_masked(void)
{
struct s5p_timer *const timer = s5p_get_base_timer();
/* reset time */
gd->arch.lastinc = readl(&timer->tcnto4);
gd->arch.tbl = 0;
}
/*
* 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.
*/
unsigned long get_tbclk(void)
{
return CONFIG_SYS_HZ;
}
|
