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8#include "hw/hw.h"
9#include "qemu/timer.h"
10#include "hw/ptimer.h"
11#include "qemu/host-utils.h"
12#include "sysemu/replay.h"
13
14struct ptimer_state
15{
16 uint8_t enabled;
17 uint64_t limit;
18 uint64_t delta;
19 uint32_t period_frac;
20 int64_t period;
21 int64_t last_event;
22 int64_t next_event;
23 QEMUBH *bh;
24 QEMUTimer *timer;
25};
26
27
28static void ptimer_trigger(ptimer_state *s)
29{
30 if (s->bh) {
31 replay_bh_schedule_event(s->bh);
32 }
33}
34
35static void ptimer_reload(ptimer_state *s)
36{
37 if (s->delta == 0) {
38 ptimer_trigger(s);
39 s->delta = s->limit;
40 }
41 if (s->delta == 0 || s->period == 0) {
42 fprintf(stderr, "Timer with period zero, disabling\n");
43 s->enabled = 0;
44 return;
45 }
46
47 s->last_event = s->next_event;
48 s->next_event = s->last_event + s->delta * s->period;
49 if (s->period_frac) {
50 s->next_event += ((int64_t)s->period_frac * s->delta) >> 32;
51 }
52 timer_mod(s->timer, s->next_event);
53}
54
55static void ptimer_tick(void *opaque)
56{
57 ptimer_state *s = (ptimer_state *)opaque;
58 ptimer_trigger(s);
59 s->delta = 0;
60 if (s->enabled == 2) {
61 s->enabled = 0;
62 } else {
63 ptimer_reload(s);
64 }
65}
66
67uint64_t ptimer_get_count(ptimer_state *s)
68{
69 int64_t now;
70 uint64_t counter;
71
72 if (s->enabled) {
73 now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
74
75 if (now - s->next_event > 0
76 || s->period == 0) {
77
78
79 counter = 0;
80 } else {
81 uint64_t rem;
82 uint64_t div;
83 int clz1, clz2;
84 int shift;
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95
96 rem = s->next_event - now;
97 div = s->period;
98
99 clz1 = clz64(rem);
100 clz2 = clz64(div);
101 shift = clz1 < clz2 ? clz1 : clz2;
102
103 rem <<= shift;
104 div <<= shift;
105 if (shift >= 32) {
106 div |= ((uint64_t)s->period_frac << (shift - 32));
107 } else {
108 if (shift != 0)
109 div |= (s->period_frac >> (32 - shift));
110
111
112 if ((uint32_t)(s->period_frac << shift))
113 div += 1;
114 }
115 counter = rem / div;
116 }
117 } else {
118 counter = s->delta;
119 }
120 return counter;
121}
122
123void ptimer_set_count(ptimer_state *s, uint64_t count)
124{
125 s->delta = count;
126 if (s->enabled) {
127 s->next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
128 ptimer_reload(s);
129 }
130}
131
132void ptimer_run(ptimer_state *s, int oneshot)
133{
134 if (s->enabled) {
135 return;
136 }
137 if (s->period == 0) {
138 fprintf(stderr, "Timer with period zero, disabling\n");
139 return;
140 }
141 s->enabled = oneshot ? 2 : 1;
142 s->next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
143 ptimer_reload(s);
144}
145
146
147
148void ptimer_stop(ptimer_state *s)
149{
150 if (!s->enabled)
151 return;
152
153 s->delta = ptimer_get_count(s);
154 timer_del(s->timer);
155 s->enabled = 0;
156}
157
158
159void ptimer_set_period(ptimer_state *s, int64_t period)
160{
161 s->period = period;
162 s->period_frac = 0;
163 if (s->enabled) {
164 s->next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
165 ptimer_reload(s);
166 }
167}
168
169
170void ptimer_set_freq(ptimer_state *s, uint32_t freq)
171{
172 s->period = 1000000000ll / freq;
173 s->period_frac = (1000000000ll << 32) / freq;
174 if (s->enabled) {
175 s->next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
176 ptimer_reload(s);
177 }
178}
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181
182void ptimer_set_limit(ptimer_state *s, uint64_t limit, int reload)
183{
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192
193 if (!use_icount && limit * s->period < 10000 && s->period) {
194 limit = 10000 / s->period;
195 }
196
197 s->limit = limit;
198 if (reload)
199 s->delta = limit;
200 if (s->enabled && reload) {
201 s->next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
202 ptimer_reload(s);
203 }
204}
205
206const VMStateDescription vmstate_ptimer = {
207 .name = "ptimer",
208 .version_id = 1,
209 .minimum_version_id = 1,
210 .fields = (VMStateField[]) {
211 VMSTATE_UINT8(enabled, ptimer_state),
212 VMSTATE_UINT64(limit, ptimer_state),
213 VMSTATE_UINT64(delta, ptimer_state),
214 VMSTATE_UINT32(period_frac, ptimer_state),
215 VMSTATE_INT64(period, ptimer_state),
216 VMSTATE_INT64(last_event, ptimer_state),
217 VMSTATE_INT64(next_event, ptimer_state),
218 VMSTATE_TIMER_PTR(timer, ptimer_state),
219 VMSTATE_END_OF_LIST()
220 }
221};
222
223ptimer_state *ptimer_init(QEMUBH *bh)
224{
225 ptimer_state *s;
226
227 s = (ptimer_state *)g_malloc0(sizeof(ptimer_state));
228 s->bh = bh;
229 s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, ptimer_tick, s);
230 return s;
231}
232