aboutsummaryrefslogtreecommitdiff
path: root/arch/mn10300/unit-asb2305/include/unit/timex.h
blob: cd8bc14e3ca38eeb54bf5cfede69cfcdf0a70ec1 (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
/* ASB2305-specific timer specifications
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public Licence
 * as published by the Free Software Foundation; either version
 * 2 of the Licence, or (at your option) any later version.
 */
#ifndef _ASM_UNIT_TIMEX_H
#define _ASM_UNIT_TIMEX_H

#ifndef __ASSEMBLY__
#include <linux/irq.h>
#endif /* __ASSEMBLY__ */

#include <asm/timer-regs.h>
#include <unit/clock.h>
#include <asm/param.h>

/*
 * jiffies counter specifications
 */

#define	TMJCBR_MAX		0xffff
#define	TMJCBC			TM01BC

#define	TMJCMD			TM01MD
#define	TMJCBR			TM01BR
#define	TMJCIRQ			TM1IRQ
#define	TMJCICR			TM1ICR

#ifndef __ASSEMBLY__

#define MN10300_SRC_IOCLK	MN10300_IOCLK

#ifndef HZ
# error HZ undeclared.
#endif /* !HZ */
/* use as little prescaling as possible to avoid losing accuracy */
#if (MN10300_SRC_IOCLK + HZ / 2) / HZ - 1 <= TMJCBR_MAX
# define IOCLK_PRESCALE		1
# define JC_TIMER_CLKSRC	TM0MD_SRC_IOCLK
# define TSC_TIMER_CLKSRC	TM4MD_SRC_IOCLK
#elif (MN10300_SRC_IOCLK / 8 + HZ / 2) / HZ - 1 <= TMJCBR_MAX
# define IOCLK_PRESCALE		8
# define JC_TIMER_CLKSRC	TM0MD_SRC_IOCLK_8
# define TSC_TIMER_CLKSRC	TM4MD_SRC_IOCLK_8
#elif (MN10300_SRC_IOCLK / 32 + HZ / 2) / HZ - 1 <= TMJCBR_MAX
# define IOCLK_PRESCALE		32
# define JC_TIMER_CLKSRC	TM0MD_SRC_IOCLK_32
# define TSC_TIMER_CLKSRC	TM4MD_SRC_IOCLK_32
#else
# error You lose.
#endif

#define MN10300_JCCLK		(MN10300_SRC_IOCLK / IOCLK_PRESCALE)
#define MN10300_TSCCLK		(MN10300_SRC_IOCLK / IOCLK_PRESCALE)

#define MN10300_JC_PER_HZ	((MN10300_JCCLK + HZ / 2) / HZ)
#define MN10300_TSC_PER_HZ	((MN10300_TSCCLK + HZ / 2) / HZ)

static inline void startup_jiffies_counter(void)
{
	u16 md, t16;

	md = JC_TIMER_CLKSRC;
	TMJCBR = MN10300_JC_PER_HZ - 1;
	t16 = TMJCBR;

	TMJCMD =
		md |
		TM1MD_SRC_TM0CASCADE << 8 |
		TM0MD_INIT_COUNTER |
		TM1MD_INIT_COUNTER << 8;

	TMJCMD =
		md |
		TM1MD_SRC_TM0CASCADE << 8 |
		TM0MD_COUNT_ENABLE |
		TM1MD_COUNT_ENABLE << 8;

	t16 = TMJCMD;

	TMJCICR |= GxICR_ENABLE | GxICR_DETECT | GxICR_REQUEST;
	t16 = TMJCICR;
}

static inline void shutdown_jiffies_counter(void)
{
}

#endif /* !__ASSEMBLY__ */


/*
 * timestamp counter specifications
 */

#define	TMTSCBR_MAX		0xffffffff
#define	TMTSCBC			TM45BC

#ifndef __ASSEMBLY__

static inline void startup_timestamp_counter(void)
{
	u32 t32;

	/* set up timer 4 & 5 cascaded as a 32-bit counter to count real time
	 * - count down from 4Gig-1 to 0 and wrap at IOCLK rate
	 */
	TM45BR = TMTSCBR_MAX;
	t32 = TM45BR;

	TM4MD = TSC_TIMER_CLKSRC;
	TM4MD |= TM4MD_INIT_COUNTER;
	TM4MD &= ~TM4MD_INIT_COUNTER;
	TM4ICR = 0;
	t32 = TM4ICR;

	TM5MD = TM5MD_SRC_TM4CASCADE;
	TM5MD |= TM5MD_INIT_COUNTER;
	TM5MD &= ~TM5MD_INIT_COUNTER;
	TM5ICR = 0;
	t32 = TM5ICR;

	TM5MD |= TM5MD_COUNT_ENABLE;
	TM4MD |= TM4MD_COUNT_ENABLE;
	t32 = TM5MD;
	t32 = TM4MD;
}

static inline void shutdown_timestamp_counter(void)
{
	u8 t8;
	TM4MD = 0;
	TM5MD = 0;
	t8 = TM4MD;
	t8 = TM5MD;
}

/*
 * we use a cascaded pair of 16-bit down-counting timers to count I/O
 * clock cycles for the purposes of time keeping
 */
typedef unsigned long cycles_t;

static inline cycles_t read_timestamp_counter(void)
{
	return (cycles_t)TMTSCBC;
}

#endif /* !__ASSEMBLY__ */

#endif /* _ASM_UNIT_TIMEX_H */