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8#include "qemu/osdep.h"
9#include "hw/hw.h"
10#include "qemu/timer.h"
11#include "hw/ptimer.h"
12#include "qemu/host-utils.h"
13#include "sysemu/replay.h"
14
15struct ptimer_state
16{
17 uint8_t enabled;
18 uint64_t limit;
19 uint64_t delta;
20 uint32_t period_frac;
21 int64_t period;
22 int64_t last_event;
23 int64_t next_event;
24 QEMUBH *bh;
25 QEMUTimer *timer;
26};
27
28
29static void ptimer_trigger(ptimer_state *s)
30{
31 if (s->bh) {
32 replay_bh_schedule_event(s->bh);
33 }
34}
35
36static void ptimer_reload(ptimer_state *s)
37{
38 if (s->delta == 0) {
39 ptimer_trigger(s);
40 s->delta = s->limit;
41 }
42 if (s->delta == 0 || s->period == 0) {
43 fprintf(stderr, "Timer with period zero, disabling\n");
44 s->enabled = 0;
45 return;
46 }
47
48 s->last_event = s->next_event;
49 s->next_event = s->last_event + s->delta * s->period;
50 if (s->period_frac) {
51 s->next_event += ((int64_t)s->period_frac * s->delta) >> 32;
52 }
53 timer_mod(s->timer, s->next_event);
54}
55
56static void ptimer_tick(void *opaque)
57{
58 ptimer_state *s = (ptimer_state *)opaque;
59 ptimer_trigger(s);
60 s->delta = 0;
61 if (s->enabled == 2) {
62 s->enabled = 0;
63 } else {
64 ptimer_reload(s);
65 }
66}
67
68uint64_t ptimer_get_count(ptimer_state *s)
69{
70 int64_t now;
71 uint64_t counter;
72
73 if (s->enabled) {
74 now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
75
76 if (now - s->next_event > 0
77 || s->period == 0) {
78
79
80 counter = 0;
81 } else {
82 uint64_t rem;
83 uint64_t div;
84 int clz1, clz2;
85 int shift;
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97 rem = s->next_event - now;
98 div = s->period;
99
100 clz1 = clz64(rem);
101 clz2 = clz64(div);
102 shift = clz1 < clz2 ? clz1 : clz2;
103
104 rem <<= shift;
105 div <<= shift;
106 if (shift >= 32) {
107 div |= ((uint64_t)s->period_frac << (shift - 32));
108 } else {
109 if (shift != 0)
110 div |= (s->period_frac >> (32 - shift));
111
112
113 if ((uint32_t)(s->period_frac << shift))
114 div += 1;
115 }
116 counter = rem / div;
117 }
118 } else {
119 counter = s->delta;
120 }
121 return counter;
122}
123
124void ptimer_set_count(ptimer_state *s, uint64_t count)
125{
126 s->delta = count;
127 if (s->enabled) {
128 s->next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
129 ptimer_reload(s);
130 }
131}
132
133void ptimer_run(ptimer_state *s, int oneshot)
134{
135 if (s->enabled) {
136 return;
137 }
138 if (s->period == 0) {
139 fprintf(stderr, "Timer with period zero, disabling\n");
140 return;
141 }
142 s->enabled = oneshot ? 2 : 1;
143 s->next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
144 ptimer_reload(s);
145}
146
147
148
149void ptimer_stop(ptimer_state *s)
150{
151 if (!s->enabled)
152 return;
153
154 s->delta = ptimer_get_count(s);
155 timer_del(s->timer);
156 s->enabled = 0;
157}
158
159
160void ptimer_set_period(ptimer_state *s, int64_t period)
161{
162 s->period = period;
163 s->period_frac = 0;
164 if (s->enabled) {
165 s->next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
166 ptimer_reload(s);
167 }
168}
169
170
171void ptimer_set_freq(ptimer_state *s, uint32_t freq)
172{
173 s->period = 1000000000ll / freq;
174 s->period_frac = (1000000000ll << 32) / freq;
175 if (s->enabled) {
176 s->next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
177 ptimer_reload(s);
178 }
179}
180
181
182
183void ptimer_set_limit(ptimer_state *s, uint64_t limit, int reload)
184{
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193
194 if (!use_icount && limit * s->period < 10000 && s->period) {
195 limit = 10000 / s->period;
196 }
197
198 s->limit = limit;
199 if (reload)
200 s->delta = limit;
201 if (s->enabled && reload) {
202 s->next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
203 ptimer_reload(s);
204 }
205}
206
207const VMStateDescription vmstate_ptimer = {
208 .name = "ptimer",
209 .version_id = 1,
210 .minimum_version_id = 1,
211 .fields = (VMStateField[]) {
212 VMSTATE_UINT8(enabled, ptimer_state),
213 VMSTATE_UINT64(limit, ptimer_state),
214 VMSTATE_UINT64(delta, ptimer_state),
215 VMSTATE_UINT32(period_frac, ptimer_state),
216 VMSTATE_INT64(period, ptimer_state),
217 VMSTATE_INT64(last_event, ptimer_state),
218 VMSTATE_INT64(next_event, ptimer_state),
219 VMSTATE_TIMER_PTR(timer, ptimer_state),
220 VMSTATE_END_OF_LIST()
221 }
222};
223
224ptimer_state *ptimer_init(QEMUBH *bh)
225{
226 ptimer_state *s;
227
228 s = (ptimer_state *)g_malloc0(sizeof(ptimer_state));
229 s->bh = bh;
230 s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, ptimer_tick, s);
231 return s;
232}
233