summaryrefslogtreecommitdiff
path: root/lib_sh/time_sh2.c
blob: 789b46f0e0261273cfb2545f34bfc3254a7be29c (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
/*
 * Copyright (C) 2007,2008 Nobobuhiro Iwamatsu <iwamatsu@nigauri.org>
 * Copyright (C) 2008 Renesas Solutions Corp.
 *
 * (C) Copyright 2003
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */

#include <common.h>
#include <asm/io.h>
#include <asm/processor.h>

#define CMT_CMCSR_INIT	0x0001	/* PCLK/32 */
#define CMT_CMCSR_CALIB 0x0000
#define CMT_MAX_COUNTER (0xFFFFFFFF)
#define CMT_TIMER_RESET (0xFFFF)

static vu_long cmt0_timer;

static void cmt_timer_start(unsigned int timer)
{
	writew(readw(CMSTR) | 0x01, CMSTR);
}

static void cmt_timer_stop(unsigned int timer)
{
	writew(readw(CMSTR) & ~0x01, CMSTR);
}

int timer_init(void)
{
	cmt0_timer = 0;
	/* Divide clock by 32 */
	readw(CMCSR_0);
	writew(CMT_CMCSR_INIT, CMCSR_0);

	/* User Device 0 only */
	cmt_timer_stop(0);
	set_timer(CMT_TIMER_RESET);
	cmt_timer_start(0);

	return 0;
}

unsigned long long get_ticks(void)
{
	return cmt0_timer;
}

static vu_long cmcnt = 0;
static unsigned long get_usec (void)
{
	ulong data = readw(CMCNT_0);

	if (data >= cmcnt)
		cmcnt = data - cmcnt;
	else
		cmcnt = (CMT_TIMER_RESET - cmcnt) + data;

	if ((cmt0_timer + cmcnt) > CMT_MAX_COUNTER)
		cmt0_timer = ((cmt0_timer + cmcnt) - CMT_MAX_COUNTER);
	else
		cmt0_timer += cmcnt;

	cmcnt = data;
	return cmt0_timer;
}

/* return msec */
ulong get_timer(ulong base)
{
	return (get_usec() / 1000) - base;
}

void set_timer(ulong t)
{
	writew((u16) t, CMCOR_0);
}

void reset_timer(void)
{
	cmt_timer_stop(0);
	set_timer(CMT_TIMER_RESET);
	cmt0_timer = 0;
	cmt_timer_start(0);
}

void __udelay(unsigned long usec)
{
	unsigned long end = get_usec() + usec;

	while (get_usec() < end)
		continue;
}

unsigned long get_tbclk(void)
{
	return CONFIG_SYS_HZ;
}