blob: 3dff3d768d1ca8355ed1cd88267a5df3f21f452f (
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
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
|
// SPDX-License-Identifier: GPL-2.0+
/*
* Freescale i.MX28 timer driver
*
* Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
* on behalf of DENX Software Engineering GmbH
*
* Based on code from LTIB:
* (C) Copyright 2009-2010 Freescale Semiconductor, Inc.
*/
#include <common.h>
#include <init.h>
#include <time.h>
#include <asm/global_data.h>
#include <asm/io.h>
#include <asm/arch/imx-regs.h>
#include <asm/arch/sys_proto.h>
#include <linux/delay.h>
/* Maximum fixed count */
#if defined(CONFIG_MX23)
#define TIMER_LOAD_VAL 0xffff
#elif defined(CONFIG_MX28)
#define TIMER_LOAD_VAL 0xffffffff
#endif
DECLARE_GLOBAL_DATA_PTR;
#define timestamp (gd->arch.tbl)
#define lastdec (gd->arch.lastinc)
/*
* This driver uses 1kHz clock source.
*/
#define MXS_INCREMENTER_HZ 1000
static inline unsigned long tick_to_time(unsigned long tick)
{
return tick / (MXS_INCREMENTER_HZ / CONFIG_SYS_HZ);
}
static inline unsigned long time_to_tick(unsigned long time)
{
return time * (MXS_INCREMENTER_HZ / CONFIG_SYS_HZ);
}
/* Calculate how many ticks happen in "us" microseconds */
static inline unsigned long us_to_tick(unsigned long us)
{
return (us * MXS_INCREMENTER_HZ) / 1000000;
}
int timer_init(void)
{
struct mxs_timrot_regs *timrot_regs =
(struct mxs_timrot_regs *)MXS_TIMROT_BASE;
/* Reset Timers and Rotary Encoder module */
mxs_reset_block(&timrot_regs->hw_timrot_rotctrl_reg);
/* Set fixed_count to 0 */
#if defined(CONFIG_MX23)
writel(0, &timrot_regs->hw_timrot_timcount0);
#elif defined(CONFIG_MX28)
writel(0, &timrot_regs->hw_timrot_fixed_count0);
#endif
/* Set UPDATE bit and 1Khz frequency */
writel(TIMROT_TIMCTRLn_UPDATE | TIMROT_TIMCTRLn_RELOAD |
TIMROT_TIMCTRLn_SELECT_1KHZ_XTAL,
&timrot_regs->hw_timrot_timctrl0);
/* Set fixed_count to maximal value */
#if defined(CONFIG_MX23)
writel(TIMER_LOAD_VAL - 1, &timrot_regs->hw_timrot_timcount0);
#elif defined(CONFIG_MX28)
writel(TIMER_LOAD_VAL, &timrot_regs->hw_timrot_fixed_count0);
#endif
return 0;
}
unsigned long long get_ticks(void)
{
struct mxs_timrot_regs *timrot_regs =
(struct mxs_timrot_regs *)MXS_TIMROT_BASE;
uint32_t now;
/* Current tick value */
#if defined(CONFIG_MX23)
/* Upper bits are the valid ones. */
now = readl(&timrot_regs->hw_timrot_timcount0) >>
TIMROT_RUNNING_COUNTn_RUNNING_COUNT_OFFSET;
#elif defined(CONFIG_MX28)
now = readl(&timrot_regs->hw_timrot_running_count0);
#else
#error "Don't know how to read timrot_regs"
#endif
if (lastdec >= now) {
/*
* normal mode (non roll)
* move stamp forward with absolut diff ticks
*/
timestamp += (lastdec - now);
} else {
/* we have rollover of decrementer */
timestamp += (TIMER_LOAD_VAL - now) + lastdec;
}
lastdec = now;
return timestamp;
}
ulong get_timer(ulong base)
{
return tick_to_time(get_ticks()) - base;
}
/* We use the HW_DIGCTL_MICROSECONDS register for sub-millisecond timer. */
#define MXS_HW_DIGCTL_MICROSECONDS 0x8001c0c0
void __udelay(unsigned long usec)
{
uint32_t old, new, incr;
uint32_t counter = 0;
old = readl(MXS_HW_DIGCTL_MICROSECONDS);
while (counter < usec) {
new = readl(MXS_HW_DIGCTL_MICROSECONDS);
/* Check if the timer wrapped. */
if (new < old) {
incr = 0xffffffff - old;
incr += new;
} else {
incr = new - old;
}
/*
* Check if we are close to the maximum time and the counter
* would wrap if incremented. If that's the case, break out
* from the loop as the requested delay time passed.
*/
if (counter + incr < counter)
break;
counter += incr;
old = new;
}
}
ulong get_tbclk(void)
{
return MXS_INCREMENTER_HZ;
}
|
