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8#include <linux/clk.h>
9#include <linux/clockchips.h>
10#include <linux/init.h>
11#include <linux/interrupt.h>
12#include <linux/irq.h>
13#include <linux/kernel.h>
14#include <linux/time.h>
15#include <linux/cpu.h>
16
17#include <asm/sysreg.h>
18
19#include <mach/pm.h>
20
21
22static cycle_t read_cycle_count(struct clocksource *cs)
23{
24 return (cycle_t)sysreg_read(COUNT);
25}
26
27
28
29
30
31
32
33
34static struct clocksource counter = {
35 .name = "avr32_counter",
36 .rating = 50,
37 .read = read_cycle_count,
38 .mask = CLOCKSOURCE_MASK(32),
39 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
40};
41
42static irqreturn_t timer_interrupt(int irq, void *dev_id)
43{
44 struct clock_event_device *evdev = dev_id;
45
46 if (unlikely(!(intc_get_pending(0) & 1)))
47 return IRQ_NONE;
48
49
50
51
52
53 sysreg_write(COMPARE, 0);
54
55 evdev->event_handler(evdev);
56 return IRQ_HANDLED;
57}
58
59static struct irqaction timer_irqaction = {
60 .handler = timer_interrupt,
61
62 .flags = IRQF_TIMER | IRQF_SHARED,
63 .name = "avr32_comparator",
64};
65
66static int comparator_next_event(unsigned long delta,
67 struct clock_event_device *evdev)
68{
69 unsigned long flags;
70
71 raw_local_irq_save(flags);
72
73
74
75
76 sysreg_write(COMPARE, (sysreg_read(COUNT) + delta) ? : 1);
77
78 raw_local_irq_restore(flags);
79
80 return 0;
81}
82
83static void comparator_mode(enum clock_event_mode mode,
84 struct clock_event_device *evdev)
85{
86 switch (mode) {
87 case CLOCK_EVT_MODE_ONESHOT:
88 pr_debug("%s: start\n", evdev->name);
89
90 case CLOCK_EVT_MODE_RESUME:
91
92
93
94
95 cpu_idle_poll_ctrl(true);
96 break;
97 case CLOCK_EVT_MODE_UNUSED:
98 case CLOCK_EVT_MODE_SHUTDOWN:
99 sysreg_write(COMPARE, 0);
100 pr_debug("%s: stop\n", evdev->name);
101 if (evdev->mode == CLOCK_EVT_MODE_ONESHOT ||
102 evdev->mode == CLOCK_EVT_MODE_RESUME) {
103
104
105
106
107 cpu_idle_poll_ctrl(false);
108 }
109 break;
110 default:
111 BUG();
112 }
113}
114
115static struct clock_event_device comparator = {
116 .name = "avr32_comparator",
117 .features = CLOCK_EVT_FEAT_ONESHOT,
118 .shift = 16,
119 .rating = 50,
120 .set_next_event = comparator_next_event,
121 .set_mode = comparator_mode,
122};
123
124void read_persistent_clock(struct timespec *ts)
125{
126 ts->tv_sec = mktime(2007, 1, 1, 0, 0, 0);
127 ts->tv_nsec = 0;
128}
129
130void __init time_init(void)
131{
132 unsigned long counter_hz;
133 int ret;
134
135
136 counter_hz = clk_get_rate(boot_cpu_data.clk);
137 ret = clocksource_register_hz(&counter, counter_hz);
138 if (ret)
139 pr_debug("timer: could not register clocksource: %d\n", ret);
140
141
142 comparator.mult = div_sc(counter_hz, NSEC_PER_SEC, comparator.shift);
143 comparator.max_delta_ns = clockevent_delta2ns((u32)~0, &comparator);
144 comparator.min_delta_ns = clockevent_delta2ns(50, &comparator) + 1;
145 comparator.cpumask = cpumask_of(0);
146
147 sysreg_write(COMPARE, 0);
148 timer_irqaction.dev_id = &comparator;
149
150 ret = setup_irq(0, &timer_irqaction);
151 if (ret)
152 pr_debug("timer: could not request IRQ 0: %d\n", ret);
153 else {
154 clockevents_register_device(&comparator);
155
156 pr_info("%s: irq 0, %lu.%03lu MHz\n", comparator.name,
157 ((counter_hz + 500) / 1000) / 1000,
158 ((counter_hz + 500) / 1000) % 1000);
159 }
160}
161