aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-ns9xxx/time-ns9360.c
blob: 77281260358a504f3f5be293074636b8502deed8 (plain) (blame)
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
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
/*
 * arch/arm/mach-ns9xxx/time-ns9360.c
 *
 * Copyright (C) 2006,2007 by Digi International Inc.
 * All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 */
#include <linux/jiffies.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/stringify.h>
#include <linux/clocksource.h>
#include <linux/clockchips.h>

#include <mach/processor-ns9360.h>
#include <mach/regs-sys-ns9360.h>
#include <mach/irqs.h>
#include <mach/system.h>
#include "generic.h"

#define TIMER_CLOCKSOURCE 0
#define TIMER_CLOCKEVENT 1
static u32 latch;

static cycle_t ns9360_clocksource_read(struct clocksource *cs)
{
	return __raw_readl(SYS_TR(TIMER_CLOCKSOURCE));
}

static struct clocksource ns9360_clocksource = {
	.name	= "ns9360-timer" __stringify(TIMER_CLOCKSOURCE),
	.rating	= 300,
	.read	= ns9360_clocksource_read,
	.mask	= CLOCKSOURCE_MASK(32),
	.shift	= 20,
	.flags	= CLOCK_SOURCE_IS_CONTINUOUS,
};

static void ns9360_clockevent_setmode(enum clock_event_mode mode,
		struct clock_event_device *clk)
{
	u32 tc = __raw_readl(SYS_TC(TIMER_CLOCKEVENT));

	switch (mode) {
	case CLOCK_EVT_MODE_PERIODIC:
		__raw_writel(latch, SYS_TRC(TIMER_CLOCKEVENT));
		REGSET(tc, SYS_TCx, REN, EN);
		REGSET(tc, SYS_TCx, INTS, EN);
		REGSET(tc, SYS_TCx, TEN, EN);
		break;

	case CLOCK_EVT_MODE_ONESHOT:
		REGSET(tc, SYS_TCx, REN, DIS);
		REGSET(tc, SYS_TCx, INTS, EN);

		/* fall through */

	case CLOCK_EVT_MODE_UNUSED:
	case CLOCK_EVT_MODE_SHUTDOWN:
	case CLOCK_EVT_MODE_RESUME:
	default:
		REGSET(tc, SYS_TCx, TEN, DIS);
		break;
	}

	__raw_writel(tc, SYS_TC(TIMER_CLOCKEVENT));
}

static int ns9360_clockevent_setnextevent(unsigned long evt,
		struct clock_event_device *clk)
{
	u32 tc = __raw_readl(SYS_TC(TIMER_CLOCKEVENT));

	if (REGGET(tc, SYS_TCx, TEN)) {
		REGSET(tc, SYS_TCx, TEN, DIS);
		__raw_writel(tc, SYS_TC(TIMER_CLOCKEVENT));
	}

	REGSET(tc, SYS_TCx, TEN, EN);

	__raw_writel(evt, SYS_TRC(TIMER_CLOCKEVENT));

	__raw_writel(tc, SYS_TC(TIMER_CLOCKEVENT));

	return 0;
}

static struct clock_event_device ns9360_clockevent_device = {
	.name		= "ns9360-timer" __stringify(TIMER_CLOCKEVENT),
	.shift		= 20,
	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
	.set_mode	= ns9360_clockevent_setmode,
	.set_next_event	= ns9360_clockevent_setnextevent,
};

static irqreturn_t ns9360_clockevent_handler(int irq, void *dev_id)
{
	int timerno = irq - IRQ_NS9360_TIMER0;
	u32 tc;

	struct clock_event_device *evt = &ns9360_clockevent_device;

	/* clear irq */
	tc = __raw_readl(SYS_TC(timerno));
	if (REGGET(tc, SYS_TCx, REN) == SYS_TCx_REN_DIS) {
		REGSET(tc, SYS_TCx, TEN, DIS);
		__raw_writel(tc, SYS_TC(timerno));
	}
	REGSET(tc, SYS_TCx, INTC, SET);
	__raw_writel(tc, SYS_TC(timerno));
	REGSET(tc, SYS_TCx, INTC, UNSET);
	__raw_writel(tc, SYS_TC(timerno));

	evt->event_handler(evt);

	return IRQ_HANDLED;
}

static struct irqaction ns9360_clockevent_action = {
	.name		= "ns9360-timer" __stringify(TIMER_CLOCKEVENT),
	.flags		= IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
	.handler	= ns9360_clockevent_handler,
};

static void __init ns9360_timer_init(void)
{
	int tc;

	tc = __raw_readl(SYS_TC(TIMER_CLOCKSOURCE));
	if (REGGET(tc, SYS_TCx, TEN)) {
		REGSET(tc, SYS_TCx, TEN, DIS);
		__raw_writel(tc, SYS_TC(TIMER_CLOCKSOURCE));
	}

	__raw_writel(0, SYS_TRC(TIMER_CLOCKSOURCE));

	REGSET(tc, SYS_TCx, TEN, EN);
	REGSET(tc, SYS_TCx, TDBG, STOP);
	REGSET(tc, SYS_TCx, TLCS, CPU);
	REGSET(tc, SYS_TCx, TM, IEE);
	REGSET(tc, SYS_TCx, INTS, DIS);
	REGSET(tc, SYS_TCx, UDS, UP);
	REGSET(tc, SYS_TCx, TSZ, 32);
	REGSET(tc, SYS_TCx, REN, EN);

	__raw_writel(tc, SYS_TC(TIMER_CLOCKSOURCE));

	ns9360_clocksource.mult = clocksource_hz2mult(ns9360_cpuclock(),
			ns9360_clocksource.shift);

	clocksource_register(&ns9360_clocksource);

	latch = SH_DIV(ns9360_cpuclock(), HZ, 0);

	tc = __raw_readl(SYS_TC(TIMER_CLOCKEVENT));
	REGSET(tc, SYS_TCx, TEN, DIS);
	REGSET(tc, SYS_TCx, TDBG, STOP);
	REGSET(tc, SYS_TCx, TLCS, CPU);
	REGSET(tc, SYS_TCx, TM, IEE);
	REGSET(tc, SYS_TCx, INTS, DIS);
	REGSET(tc, SYS_TCx, UDS, DOWN);
	REGSET(tc, SYS_TCx, TSZ, 32);
	REGSET(tc, SYS_TCx, REN, EN);
	__raw_writel(tc, SYS_TC(TIMER_CLOCKEVENT));

	ns9360_clockevent_device.mult = div_sc(ns9360_cpuclock(),
			NSEC_PER_SEC, ns9360_clockevent_device.shift);
	ns9360_clockevent_device.max_delta_ns =
		clockevent_delta2ns(-1, &ns9360_clockevent_device);
	ns9360_clockevent_device.min_delta_ns =
		clockevent_delta2ns(1, &ns9360_clockevent_device);

	ns9360_clockevent_device.cpumask = cpumask_of(0);
	clockevents_register_device(&ns9360_clockevent_device);

	setup_irq(IRQ_NS9360_TIMER0 + TIMER_CLOCKEVENT,
			&ns9360_clockevent_action);
}

struct sys_timer ns9360_timer = {
	.init = ns9360_timer_init,
};