summaryrefslogtreecommitdiffstats
path: root/target/linux/xburst/files-2.6.32/arch/mips/jz4740/time.c
blob: b811fcd446375a0423668e476129c38e5c0990e0 (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
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
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
/*
 *  Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
 *  	JZ4740 platform timer support
 *
 *  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.
 *
 *  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.,
 *  675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/time.h>
#include <linux/clockchips.h>
#include <linux/clk.h>

#include <asm/mach-jz4740/irq.h>
#include <asm/mach-jz4740/jz4740.h>
#include <asm/time.h>

#define JZ_REG_TIMER_STOP		0x1C
#define JZ_REG_TIMER_STOP_SET		0x2C
#define JZ_REG_TIMER_STOP_CLEAR		0x3C
#define JZ_REG_TIMER_ENABLE		0x10
#define JZ_REG_TIMER_ENABLE_SET		0x14
#define JZ_REG_TIMER_ENABLE_CLEAR	0x18
#define JZ_REG_TIMER_FLAG		0x20
#define JZ_REG_TIMER_FLAG_SET		0x24
#define JZ_REG_TIMER_FLAG_CLEAR		0x28
#define JZ_REG_TIMER_MASK		0x30
#define JZ_REG_TIMER_MASK_SET		0x34
#define JZ_REG_TIMER_MASK_CLEAR		0x38

#define JZ_REG_TIMER_DFR(x) (((x) * 0x10) + 0x40)
#define JZ_REG_TIMER_DHR(x) (((x) * 0x10) + 0x44)
#define JZ_REG_TIMER_CNT(x) (((x) * 0x10) + 0x48)
#define JZ_REG_TIMER_CTRL(x) (((x) * 0x10) + 0x4C)

#define JZ_TIMER_IRQ_HALF(x) BIT((x) + 0x10)
#define JZ_TIMER_IRQ_FULL(x) BIT(x)

#define JZ_TIMER_CTRL_PWM_ACTIVE_LOW	BIT(8)
#define JZ_TIMER_CTRL_PWM_ENABLE	BIT(7)
#define JZ_TIMER_CTRL_PRESCALE_MASK	0x1c
#define JZ_TIMER_CTRL_PRESCALE_OFFSET	0x3
#define JZ_TIMER_CTRL_PRESCALE_1	(0 << 3)
#define JZ_TIMER_CTRL_PRESCALE_4	(1 << 3)
#define JZ_TIMER_CTRL_PRESCALE_16	(2 << 3)
#define JZ_TIMER_CTRL_PRESCALE_64	(3 << 3)
#define JZ_TIMER_CTRL_PRESCALE_256	(4 << 3)
#define JZ_TIMER_CTRL_PRESCALE_1024	(5 << 3)

#define JZ_TIMER_CTRL_SRC_EXT		BIT(2)
#define JZ_TIMER_CTRL_SRC_RTC		BIT(1)
#define JZ_TIMER_CTRL_SRC_PCLK		BIT(0)

static void __iomem *jz4740_timer_base;
static uint16_t jz4740_jiffies_per_tick;

void jz4740_timer_enable_watchdog(void)
{
	writel(BIT(16), jz4740_timer_base + JZ_REG_TIMER_STOP_CLEAR);
}

void jz4740_timer_disable_watchdog(void)
{
	writel(BIT(16), jz4740_timer_base + JZ_REG_TIMER_STOP_SET);
}

static inline void jz4740_timer_set_period(unsigned int timer, uint16_t period)
{
	writew(period, jz4740_timer_base + JZ_REG_TIMER_DFR(timer));
}

static inline void jz4740_timer_set_duty(unsigned int timer, uint16_t duty)
{
	writew(duty, jz4740_timer_base + JZ_REG_TIMER_DHR(timer));
}

static void jz4740_init_timer(void)
{
	uint16_t val = 0;
	val |= JZ_TIMER_CTRL_PRESCALE_16;
	val |= JZ_TIMER_CTRL_SRC_EXT;

	writew(val, jz4740_timer_base + JZ_REG_TIMER_CTRL(0));
	writew(0xffff, jz4740_timer_base + JZ_REG_TIMER_DFR(0));
	writew(val, jz4740_timer_base + JZ_REG_TIMER_CTRL(1));
	writew(0xffff, jz4740_timer_base + JZ_REG_TIMER_DFR(1));
}

static void jz4740_timer_enable(unsigned int timer)
{
	writel(BIT(timer), jz4740_timer_base + JZ_REG_TIMER_STOP_CLEAR);
	writel(BIT(timer), jz4740_timer_base + JZ_REG_TIMER_ENABLE_SET);
}

static void jz4740_timer_disable(unsigned int timer)
{
	writel(BIT(timer), jz4740_timer_base + JZ_REG_TIMER_ENABLE_CLEAR);
	writel(BIT(timer), jz4740_timer_base + JZ_REG_TIMER_STOP_SET);
}

static void jz4740_timer_irq_full_enable(unsigned int timer)
{
	writel(JZ_TIMER_IRQ_FULL(timer), jz4740_timer_base + JZ_REG_TIMER_FLAG_CLEAR);
	writel(JZ_TIMER_IRQ_FULL(timer), jz4740_timer_base + JZ_REG_TIMER_MASK_CLEAR);
}

static int jz4740_timer_irq_full_is_enabled(unsigned int timer)
{
	return !(readl(jz4740_timer_base + JZ_REG_TIMER_MASK) &
	JZ_TIMER_IRQ_FULL(timer));
}

static void jz4740_timer_irq_full_disable(unsigned int timer)
{
	writel(JZ_TIMER_IRQ_FULL(timer), jz4740_timer_base + JZ_REG_TIMER_MASK_SET);
}

static void jz4740_timer_irq_half_enable(unsigned int timer)
{
	writel(JZ_TIMER_IRQ_HALF(timer), jz4740_timer_base + JZ_REG_TIMER_FLAG_CLEAR);
	writel(JZ_TIMER_IRQ_HALF(timer), jz4740_timer_base + JZ_REG_TIMER_MASK_CLEAR);
}

static void jz4740_timer_irq_half_disable(unsigned int timer)
{
	writel(JZ_TIMER_IRQ_HALF(timer), jz4740_timer_base + JZ_REG_TIMER_MASK_SET);
}

static cycle_t jz4740_clocksource_read(struct clocksource *cs)
{
    uint16_t val;
	val = readw(jz4740_timer_base + JZ_REG_TIMER_CNT(1));
	return val;
}

static struct clocksource jz4740_clocksource = {
	.name = "jz4740-timer",
	.rating = 200,
	.read = jz4740_clocksource_read,
	.mask = CLOCKSOURCE_MASK(16),
	.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};

static irqreturn_t jz4740_clockevent_irq(int irq, void *devid)
{
	struct clock_event_device *cd = devid;

	writel(JZ_TIMER_IRQ_FULL(0), jz4740_timer_base + JZ_REG_TIMER_FLAG_CLEAR);

	if (cd->mode != CLOCK_EVT_MODE_PERIODIC) {
		jz4740_timer_disable(0);
		cd->event_handler(cd);
	 } else {
		cd->event_handler(cd);
	}

    return IRQ_HANDLED;
}

static void jz4740_clockevent_set_mode(enum clock_event_mode mode,
				       struct clock_event_device *cd)
{
	switch(mode) {
	case CLOCK_EVT_MODE_PERIODIC:
		writew(0x0, jz4740_timer_base + JZ_REG_TIMER_CNT(0));
		writew(jz4740_jiffies_per_tick, jz4740_timer_base + JZ_REG_TIMER_DFR(0));
	case CLOCK_EVT_MODE_RESUME:
		jz4740_timer_irq_full_enable(0);
		jz4740_timer_enable(0);
		break;
	case CLOCK_EVT_MODE_ONESHOT:
	case CLOCK_EVT_MODE_SHUTDOWN:
		jz4740_timer_disable(0);
		break;
	default:
		break;
	}
}

static int jz4740_clockevent_set_next(unsigned long evt, struct
clock_event_device *cd)
{
	writew(0x0, jz4740_timer_base + JZ_REG_TIMER_CNT(0));
	writew(evt, jz4740_timer_base + JZ_REG_TIMER_DFR(0));
	jz4740_timer_enable(0);

	return 0;
}

static struct clock_event_device jz4740_clockevent = {
	.name = "jz4740-timer",
	.features = CLOCK_EVT_FEAT_PERIODIC,
	.set_next_event = jz4740_clockevent_set_next,
	.set_mode = jz4740_clockevent_set_mode,
	.rating = 200,
    .irq = JZ_IRQ_TCU0,
};

static struct irqaction jz_irqaction = {
	.handler	= jz4740_clockevent_irq,
	.flags		= IRQF_PERCPU | IRQF_TIMER | IRQF_DISABLED,
	.name		= "jz4740-timerirq",
    .dev_id      = &jz4740_clockevent,
};


void __init plat_time_init(void)
{
    int ret;
	uint32_t clk_rate;
	struct clk *ext_clk;

	jz4740_timer_base = ioremap(CPHYSADDR(TCU_BASE), 0x100);

	if (!jz4740_timer_base) {
	    printk(KERN_ERR "Failed to ioremap timer registers");
	    return;
	}

	/*ext_clk = clk_get(NULL, "ext");
	clk_rate = clk_get_rate(ext_clk) >> 4;
	clk_put(ext_clk);*/


	clk_rate = JZ_EXTAL >> 4;

    jz4740_jiffies_per_tick = DIV_ROUND_CLOSEST(clk_rate, HZ);

	clockevent_set_clock(&jz4740_clockevent, clk_rate);
	jz4740_clockevent.min_delta_ns = clockevent_delta2ns(100, &jz4740_clockevent);
	jz4740_clockevent.max_delta_ns = clockevent_delta2ns(0xffff, &jz4740_clockevent);
	jz4740_clockevent.cpumask = cpumask_of(0);

	clockevents_register_device(&jz4740_clockevent);

	clocksource_set_clock(&jz4740_clocksource, clk_rate);
	ret = clocksource_register(&jz4740_clocksource);

	if (ret)
	    printk(KERN_ERR "Failed to register clocksource: %d\n", ret);

	setup_irq(JZ_IRQ_TCU0, &jz_irqaction);

	jz4740_init_timer();
	writew(jz4740_jiffies_per_tick, jz4740_timer_base + JZ_REG_TIMER_DFR(0));
    jz4740_timer_irq_half_disable(0);
    jz4740_timer_irq_full_enable(0);
	jz4740_timer_enable(0);

    jz4740_timer_irq_half_disable(1);
    jz4740_timer_irq_full_disable(1);

	jz4740_timer_enable(1);
}