1 /*
2 * ARM PrimeCell Timer modules.
3 *
4 * Copyright (c) 2005-2006 CodeSourcery.
5 * Written by Paul Brook
6 *
7 * This code is licensed under the GPL.
8 */
9
10 #include "qemu/osdep.h"
11 #include "hw/sysbus.h"
12 #include "migration/vmstate.h"
13 #include "qemu/timer.h"
14 #include "hw/irq.h"
15 #include "hw/ptimer.h"
16 #include "hw/qdev-properties.h"
17 #include "qemu/module.h"
18 #include "qemu/log.h"
19 #include "qom/object.h"
20
21 /* Common timer implementation. */
22
23 #define TIMER_CTRL_ONESHOT (1 << 0)
24 #define TIMER_CTRL_32BIT (1 << 1)
25 #define TIMER_CTRL_DIV1 (0 << 2)
26 #define TIMER_CTRL_DIV16 (1 << 2)
27 #define TIMER_CTRL_DIV256 (2 << 2)
28 #define TIMER_CTRL_IE (1 << 5)
29 #define TIMER_CTRL_PERIODIC (1 << 6)
30 #define TIMER_CTRL_ENABLE (1 << 7)
31
32 typedef struct {
33 ptimer_state *timer;
34 uint32_t control;
35 uint32_t limit;
36 int freq;
37 int int_level;
38 qemu_irq irq;
39 } arm_timer_state;
40
41 /* Check all active timers, and schedule the next timer interrupt. */
42
arm_timer_update(arm_timer_state * s)43 static void arm_timer_update(arm_timer_state *s)
44 {
45 /* Update interrupts. */
46 if (s->int_level && (s->control & TIMER_CTRL_IE)) {
47 qemu_irq_raise(s->irq);
48 } else {
49 qemu_irq_lower(s->irq);
50 }
51 }
52
arm_timer_read(void * opaque,hwaddr offset)53 static uint32_t arm_timer_read(void *opaque, hwaddr offset)
54 {
55 arm_timer_state *s = (arm_timer_state *)opaque;
56
57 switch (offset >> 2) {
58 case 0: /* TimerLoad */
59 case 6: /* TimerBGLoad */
60 return s->limit;
61 case 1: /* TimerValue */
62 return ptimer_get_count(s->timer);
63 case 2: /* TimerControl */
64 return s->control;
65 case 4: /* TimerRIS */
66 return s->int_level;
67 case 5: /* TimerMIS */
68 if ((s->control & TIMER_CTRL_IE) == 0)
69 return 0;
70 return s->int_level;
71 default:
72 qemu_log_mask(LOG_GUEST_ERROR,
73 "%s: Bad offset %x\n", __func__, (int)offset);
74 return 0;
75 }
76 }
77
78 /*
79 * Reset the timer limit after settings have changed.
80 * May only be called from inside a ptimer transaction block.
81 */
arm_timer_recalibrate(arm_timer_state * s,int reload)82 static void arm_timer_recalibrate(arm_timer_state *s, int reload)
83 {
84 uint32_t limit;
85
86 if ((s->control & (TIMER_CTRL_PERIODIC | TIMER_CTRL_ONESHOT)) == 0) {
87 /* Free running. */
88 if (s->control & TIMER_CTRL_32BIT)
89 limit = 0xffffffff;
90 else
91 limit = 0xffff;
92 } else {
93 /* Periodic. */
94 limit = s->limit;
95 }
96 ptimer_set_limit(s->timer, limit, reload);
97 }
98
arm_timer_write(void * opaque,hwaddr offset,uint32_t value)99 static void arm_timer_write(void *opaque, hwaddr offset,
100 uint32_t value)
101 {
102 arm_timer_state *s = (arm_timer_state *)opaque;
103 int freq;
104
105 switch (offset >> 2) {
106 case 0: /* TimerLoad */
107 s->limit = value;
108 ptimer_transaction_begin(s->timer);
109 arm_timer_recalibrate(s, 1);
110 ptimer_transaction_commit(s->timer);
111 break;
112 case 1: /* TimerValue */
113 /* ??? Linux seems to want to write to this readonly register.
114 Ignore it. */
115 break;
116 case 2: /* TimerControl */
117 ptimer_transaction_begin(s->timer);
118 if (s->control & TIMER_CTRL_ENABLE) {
119 /* Pause the timer if it is running. This may cause some
120 inaccuracy dure to rounding, but avoids a whole lot of other
121 messyness. */
122 ptimer_stop(s->timer);
123 }
124 s->control = value;
125 freq = s->freq;
126 /* ??? Need to recalculate expiry time after changing divisor. */
127 switch ((value >> 2) & 3) {
128 case 1: freq >>= 4; break;
129 case 2: freq >>= 8; break;
130 }
131 arm_timer_recalibrate(s, s->control & TIMER_CTRL_ENABLE);
132 ptimer_set_freq(s->timer, freq);
133 if (s->control & TIMER_CTRL_ENABLE) {
134 /* Restart the timer if still enabled. */
135 ptimer_run(s->timer, (s->control & TIMER_CTRL_ONESHOT) != 0);
136 }
137 ptimer_transaction_commit(s->timer);
138 break;
139 case 3: /* TimerIntClr */
140 s->int_level = 0;
141 break;
142 case 6: /* TimerBGLoad */
143 s->limit = value;
144 ptimer_transaction_begin(s->timer);
145 arm_timer_recalibrate(s, 0);
146 ptimer_transaction_commit(s->timer);
147 break;
148 default:
149 qemu_log_mask(LOG_GUEST_ERROR,
150 "%s: Bad offset %x\n", __func__, (int)offset);
151 }
152 arm_timer_update(s);
153 }
154
arm_timer_tick(void * opaque)155 static void arm_timer_tick(void *opaque)
156 {
157 arm_timer_state *s = (arm_timer_state *)opaque;
158 s->int_level = 1;
159 arm_timer_update(s);
160 }
161
162 static const VMStateDescription vmstate_arm_timer = {
163 .name = "arm_timer",
164 .version_id = 1,
165 .minimum_version_id = 1,
166 .fields = (const VMStateField[]) {
167 VMSTATE_UINT32(control, arm_timer_state),
168 VMSTATE_UINT32(limit, arm_timer_state),
169 VMSTATE_INT32(int_level, arm_timer_state),
170 VMSTATE_PTIMER(timer, arm_timer_state),
171 VMSTATE_END_OF_LIST()
172 }
173 };
174
arm_timer_init(uint32_t freq)175 static arm_timer_state *arm_timer_init(uint32_t freq)
176 {
177 arm_timer_state *s;
178
179 s = g_new0(arm_timer_state, 1);
180 s->freq = freq;
181 s->control = TIMER_CTRL_IE;
182
183 s->timer = ptimer_init(arm_timer_tick, s, PTIMER_POLICY_LEGACY);
184 vmstate_register_any(NULL, &vmstate_arm_timer, s);
185 return s;
186 }
187
188 /*
189 * ARM PrimeCell SP804 dual timer module.
190 * Docs at
191 * https://developer.arm.com/documentation/ddi0271/latest/
192 */
193
194 #define TYPE_SP804 "sp804"
195 OBJECT_DECLARE_SIMPLE_TYPE(SP804State, SP804)
196
197 struct SP804State {
198 SysBusDevice parent_obj;
199
200 MemoryRegion iomem;
201 arm_timer_state *timer[2];
202 uint32_t freq0, freq1;
203 int level[2];
204 qemu_irq irq;
205 };
206
207 static const uint8_t sp804_ids[] = {
208 /* Timer ID */
209 0x04, 0x18, 0x14, 0,
210 /* PrimeCell ID */
211 0xd, 0xf0, 0x05, 0xb1
212 };
213
214 /* Merge the IRQs from the two component devices. */
sp804_set_irq(void * opaque,int irq,int level)215 static void sp804_set_irq(void *opaque, int irq, int level)
216 {
217 SP804State *s = (SP804State *)opaque;
218
219 s->level[irq] = level;
220 qemu_set_irq(s->irq, s->level[0] || s->level[1]);
221 }
222
sp804_read(void * opaque,hwaddr offset,unsigned size)223 static uint64_t sp804_read(void *opaque, hwaddr offset,
224 unsigned size)
225 {
226 SP804State *s = (SP804State *)opaque;
227
228 if (offset < 0x20) {
229 return arm_timer_read(s->timer[0], offset);
230 }
231 if (offset < 0x40) {
232 return arm_timer_read(s->timer[1], offset - 0x20);
233 }
234
235 /* TimerPeriphID */
236 if (offset >= 0xfe0 && offset <= 0xffc) {
237 return sp804_ids[(offset - 0xfe0) >> 2];
238 }
239
240 switch (offset) {
241 /* Integration Test control registers, which we won't support */
242 case 0xf00: /* TimerITCR */
243 case 0xf04: /* TimerITOP (strictly write only but..) */
244 qemu_log_mask(LOG_UNIMP,
245 "%s: integration test registers unimplemented\n",
246 __func__);
247 return 0;
248 }
249
250 qemu_log_mask(LOG_GUEST_ERROR,
251 "%s: Bad offset %x\n", __func__, (int)offset);
252 return 0;
253 }
254
sp804_write(void * opaque,hwaddr offset,uint64_t value,unsigned size)255 static void sp804_write(void *opaque, hwaddr offset,
256 uint64_t value, unsigned size)
257 {
258 SP804State *s = (SP804State *)opaque;
259
260 if (offset < 0x20) {
261 arm_timer_write(s->timer[0], offset, value);
262 return;
263 }
264
265 if (offset < 0x40) {
266 arm_timer_write(s->timer[1], offset - 0x20, value);
267 return;
268 }
269
270 /* Technically we could be writing to the Test Registers, but not likely */
271 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %x\n",
272 __func__, (int)offset);
273 }
274
275 static const MemoryRegionOps sp804_ops = {
276 .read = sp804_read,
277 .write = sp804_write,
278 .endianness = DEVICE_NATIVE_ENDIAN,
279 };
280
281 static const VMStateDescription vmstate_sp804 = {
282 .name = "sp804",
283 .version_id = 1,
284 .minimum_version_id = 1,
285 .fields = (const VMStateField[]) {
286 VMSTATE_INT32_ARRAY(level, SP804State, 2),
287 VMSTATE_END_OF_LIST()
288 }
289 };
290
sp804_init(Object * obj)291 static void sp804_init(Object *obj)
292 {
293 SP804State *s = SP804(obj);
294 SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
295
296 sysbus_init_irq(sbd, &s->irq);
297 memory_region_init_io(&s->iomem, obj, &sp804_ops, s,
298 "sp804", 0x1000);
299 sysbus_init_mmio(sbd, &s->iomem);
300 }
301
sp804_realize(DeviceState * dev,Error ** errp)302 static void sp804_realize(DeviceState *dev, Error **errp)
303 {
304 SP804State *s = SP804(dev);
305
306 s->timer[0] = arm_timer_init(s->freq0);
307 s->timer[1] = arm_timer_init(s->freq1);
308 s->timer[0]->irq = qemu_allocate_irq(sp804_set_irq, s, 0);
309 s->timer[1]->irq = qemu_allocate_irq(sp804_set_irq, s, 1);
310 }
311
312 /* Integrator/CP timer module. */
313
314 #define TYPE_INTEGRATOR_PIT "integrator_pit"
315 OBJECT_DECLARE_SIMPLE_TYPE(icp_pit_state, INTEGRATOR_PIT)
316
317 struct icp_pit_state {
318 SysBusDevice parent_obj;
319
320 MemoryRegion iomem;
321 arm_timer_state *timer[3];
322 };
323
icp_pit_read(void * opaque,hwaddr offset,unsigned size)324 static uint64_t icp_pit_read(void *opaque, hwaddr offset,
325 unsigned size)
326 {
327 icp_pit_state *s = (icp_pit_state *)opaque;
328 int n;
329
330 /* ??? Don't know the PrimeCell ID for this device. */
331 n = offset >> 8;
332 if (n > 2) {
333 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad timer %d\n", __func__, n);
334 return 0;
335 }
336
337 return arm_timer_read(s->timer[n], offset & 0xff);
338 }
339
icp_pit_write(void * opaque,hwaddr offset,uint64_t value,unsigned size)340 static void icp_pit_write(void *opaque, hwaddr offset,
341 uint64_t value, unsigned size)
342 {
343 icp_pit_state *s = (icp_pit_state *)opaque;
344 int n;
345
346 n = offset >> 8;
347 if (n > 2) {
348 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad timer %d\n", __func__, n);
349 return;
350 }
351
352 arm_timer_write(s->timer[n], offset & 0xff, value);
353 }
354
355 static const MemoryRegionOps icp_pit_ops = {
356 .read = icp_pit_read,
357 .write = icp_pit_write,
358 .endianness = DEVICE_NATIVE_ENDIAN,
359 };
360
icp_pit_init(Object * obj)361 static void icp_pit_init(Object *obj)
362 {
363 icp_pit_state *s = INTEGRATOR_PIT(obj);
364 SysBusDevice *dev = SYS_BUS_DEVICE(obj);
365
366 /* Timer 0 runs at the system clock speed (40MHz). */
367 s->timer[0] = arm_timer_init(40000000);
368 /* The other two timers run at 1MHz. */
369 s->timer[1] = arm_timer_init(1000000);
370 s->timer[2] = arm_timer_init(1000000);
371
372 sysbus_init_irq(dev, &s->timer[0]->irq);
373 sysbus_init_irq(dev, &s->timer[1]->irq);
374 sysbus_init_irq(dev, &s->timer[2]->irq);
375
376 memory_region_init_io(&s->iomem, obj, &icp_pit_ops, s,
377 "icp_pit", 0x1000);
378 sysbus_init_mmio(dev, &s->iomem);
379 /* This device has no state to save/restore. The component timers will
380 save themselves. */
381 }
382
383 static const TypeInfo icp_pit_info = {
384 .name = TYPE_INTEGRATOR_PIT,
385 .parent = TYPE_SYS_BUS_DEVICE,
386 .instance_size = sizeof(icp_pit_state),
387 .instance_init = icp_pit_init,
388 };
389
390 static Property sp804_properties[] = {
391 DEFINE_PROP_UINT32("freq0", SP804State, freq0, 1000000),
392 DEFINE_PROP_UINT32("freq1", SP804State, freq1, 1000000),
393 DEFINE_PROP_END_OF_LIST(),
394 };
395
sp804_class_init(ObjectClass * klass,void * data)396 static void sp804_class_init(ObjectClass *klass, void *data)
397 {
398 DeviceClass *k = DEVICE_CLASS(klass);
399
400 k->realize = sp804_realize;
401 device_class_set_props(k, sp804_properties);
402 k->vmsd = &vmstate_sp804;
403 }
404
405 static const TypeInfo sp804_info = {
406 .name = TYPE_SP804,
407 .parent = TYPE_SYS_BUS_DEVICE,
408 .instance_size = sizeof(SP804State),
409 .instance_init = sp804_init,
410 .class_init = sp804_class_init,
411 };
412
arm_timer_register_types(void)413 static void arm_timer_register_types(void)
414 {
415 type_register_static(&icp_pit_info);
416 type_register_static(&sp804_info);
417 }
418
419 type_init(arm_timer_register_types)
420