xref: /openbmc/qemu/hw/timer/allwinner-a10-pit.c (revision effd60c8)
1 /*
2  * Allwinner A10 timer device emulation
3  *
4  * Copyright (C) 2013 Li Guang
5  * Written by Li Guang <lig.fnst@cn.fujitsu.com>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License as published by the
9  * Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful, but WITHOUT
13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15  * for more details.
16  */
17 
18 #include "qemu/osdep.h"
19 #include "hw/irq.h"
20 #include "hw/qdev-properties.h"
21 #include "hw/sysbus.h"
22 #include "hw/timer/allwinner-a10-pit.h"
23 #include "migration/vmstate.h"
24 #include "qemu/log.h"
25 #include "qemu/module.h"
26 
27 static void a10_pit_update_irq(AwA10PITState *s)
28 {
29     int i;
30 
31     for (i = 0; i < AW_A10_PIT_TIMER_NR; i++) {
32         qemu_set_irq(s->irq[i], !!(s->irq_status & s->irq_enable & (1 << i)));
33     }
34 }
35 
36 static uint64_t a10_pit_read(void *opaque, hwaddr offset, unsigned size)
37 {
38     AwA10PITState *s = AW_A10_PIT(opaque);
39     uint8_t index;
40 
41     switch (offset) {
42     case AW_A10_PIT_TIMER_IRQ_EN:
43         return s->irq_enable;
44     case AW_A10_PIT_TIMER_IRQ_ST:
45         return s->irq_status;
46     case AW_A10_PIT_TIMER_BASE ... AW_A10_PIT_TIMER_BASE_END:
47         index = offset & 0xf0;
48         index >>= 4;
49         index -= 1;
50         switch (offset & 0x0f) {
51         case AW_A10_PIT_TIMER_CONTROL:
52             return s->control[index];
53         case AW_A10_PIT_TIMER_INTERVAL:
54             return s->interval[index];
55         case AW_A10_PIT_TIMER_COUNT:
56             s->count[index] = ptimer_get_count(s->timer[index]);
57             return s->count[index];
58         default:
59             qemu_log_mask(LOG_GUEST_ERROR,
60                           "%s: Bad offset 0x%x\n",  __func__, (int)offset);
61             break;
62         }
63     case AW_A10_PIT_WDOG_CONTROL:
64         break;
65     case AW_A10_PIT_WDOG_MODE:
66         break;
67     case AW_A10_PIT_COUNT_LO:
68         return s->count_lo;
69     case AW_A10_PIT_COUNT_HI:
70         return s->count_hi;
71     case AW_A10_PIT_COUNT_CTL:
72         return s->count_ctl;
73     default:
74         qemu_log_mask(LOG_GUEST_ERROR,
75                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
76         break;
77     }
78 
79     return 0;
80 }
81 
82 /* Must be called inside a ptimer transaction block for s->timer[index] */
83 static void a10_pit_set_freq(AwA10PITState *s, int index)
84 {
85     uint32_t prescaler, source, source_freq;
86 
87     prescaler = 1 << extract32(s->control[index], 4, 3);
88     source = extract32(s->control[index], 2, 2);
89     source_freq = s->clk_freq[source];
90 
91     if (source_freq) {
92         ptimer_set_freq(s->timer[index], source_freq / prescaler);
93     } else {
94         qemu_log_mask(LOG_GUEST_ERROR, "%s: Invalid clock source %u\n",
95                       __func__, source);
96     }
97 }
98 
99 static void a10_pit_write(void *opaque, hwaddr offset, uint64_t value,
100                             unsigned size)
101 {
102      AwA10PITState *s = AW_A10_PIT(opaque);
103      uint8_t index;
104 
105     switch (offset) {
106     case AW_A10_PIT_TIMER_IRQ_EN:
107         s->irq_enable = value;
108         a10_pit_update_irq(s);
109         break;
110     case AW_A10_PIT_TIMER_IRQ_ST:
111         s->irq_status &= ~value;
112         a10_pit_update_irq(s);
113         break;
114     case AW_A10_PIT_TIMER_BASE ... AW_A10_PIT_TIMER_BASE_END:
115         index = offset & 0xf0;
116         index >>= 4;
117         index -= 1;
118         switch (offset & 0x0f) {
119         case AW_A10_PIT_TIMER_CONTROL:
120             s->control[index] = value;
121             ptimer_transaction_begin(s->timer[index]);
122             a10_pit_set_freq(s, index);
123             if (s->control[index] & AW_A10_PIT_TIMER_RELOAD) {
124                 ptimer_set_count(s->timer[index], s->interval[index]);
125             }
126             if (s->control[index] & AW_A10_PIT_TIMER_EN) {
127                 int oneshot = 0;
128                 if (s->control[index] & AW_A10_PIT_TIMER_MODE) {
129                     oneshot = 1;
130                 }
131                 ptimer_run(s->timer[index], oneshot);
132             } else {
133                 ptimer_stop(s->timer[index]);
134             }
135             ptimer_transaction_commit(s->timer[index]);
136             break;
137         case AW_A10_PIT_TIMER_INTERVAL:
138             s->interval[index] = value;
139             ptimer_transaction_begin(s->timer[index]);
140             ptimer_set_limit(s->timer[index], s->interval[index], 1);
141             ptimer_transaction_commit(s->timer[index]);
142             break;
143         case AW_A10_PIT_TIMER_COUNT:
144             s->count[index] = value;
145             break;
146         default:
147             qemu_log_mask(LOG_GUEST_ERROR,
148                           "%s: Bad offset 0x%x\n",  __func__, (int)offset);
149         }
150         break;
151     case AW_A10_PIT_WDOG_CONTROL:
152         s->watch_dog_control = value;
153         break;
154     case AW_A10_PIT_WDOG_MODE:
155         s->watch_dog_mode = value;
156         break;
157     case AW_A10_PIT_COUNT_LO:
158         s->count_lo = value;
159         break;
160     case AW_A10_PIT_COUNT_HI:
161         s->count_hi = value;
162         break;
163     case AW_A10_PIT_COUNT_CTL:
164         s->count_ctl = value;
165         if (s->count_ctl & AW_A10_PIT_COUNT_RL_EN) {
166             uint64_t  tmp_count = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
167 
168             s->count_lo = tmp_count;
169             s->count_hi = tmp_count >> 32;
170             s->count_ctl &= ~AW_A10_PIT_COUNT_RL_EN;
171         }
172         if (s->count_ctl & AW_A10_PIT_COUNT_CLR_EN) {
173             s->count_lo = 0;
174             s->count_hi = 0;
175             s->count_ctl &= ~AW_A10_PIT_COUNT_CLR_EN;
176         }
177         break;
178     default:
179         qemu_log_mask(LOG_GUEST_ERROR,
180                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
181         break;
182     }
183 }
184 
185 static const MemoryRegionOps a10_pit_ops = {
186     .read = a10_pit_read,
187     .write = a10_pit_write,
188     .endianness = DEVICE_NATIVE_ENDIAN,
189 };
190 
191 static Property a10_pit_properties[] = {
192     DEFINE_PROP_UINT32("clk0-freq", AwA10PITState, clk_freq[0], 0),
193     DEFINE_PROP_UINT32("clk1-freq", AwA10PITState, clk_freq[1], 0),
194     DEFINE_PROP_UINT32("clk2-freq", AwA10PITState, clk_freq[2], 0),
195     DEFINE_PROP_UINT32("clk3-freq", AwA10PITState, clk_freq[3], 0),
196     DEFINE_PROP_END_OF_LIST(),
197 };
198 
199 static const VMStateDescription vmstate_a10_pit = {
200     .name = "a10.pit",
201     .version_id = 1,
202     .minimum_version_id = 1,
203     .fields = (const VMStateField[]) {
204         VMSTATE_UINT32(irq_enable, AwA10PITState),
205         VMSTATE_UINT32(irq_status, AwA10PITState),
206         VMSTATE_UINT32_ARRAY(control, AwA10PITState, AW_A10_PIT_TIMER_NR),
207         VMSTATE_UINT32_ARRAY(interval, AwA10PITState, AW_A10_PIT_TIMER_NR),
208         VMSTATE_UINT32_ARRAY(count, AwA10PITState, AW_A10_PIT_TIMER_NR),
209         VMSTATE_UINT32(watch_dog_mode, AwA10PITState),
210         VMSTATE_UINT32(watch_dog_control, AwA10PITState),
211         VMSTATE_UINT32(count_lo, AwA10PITState),
212         VMSTATE_UINT32(count_hi, AwA10PITState),
213         VMSTATE_UINT32(count_ctl, AwA10PITState),
214         VMSTATE_PTIMER_ARRAY(timer, AwA10PITState, AW_A10_PIT_TIMER_NR),
215         VMSTATE_END_OF_LIST()
216     }
217 };
218 
219 static void a10_pit_reset(DeviceState *dev)
220 {
221     AwA10PITState *s = AW_A10_PIT(dev);
222     uint8_t i;
223 
224     s->irq_enable = 0;
225     s->irq_status = 0;
226     a10_pit_update_irq(s);
227 
228     for (i = 0; i < 6; i++) {
229         s->control[i] = AW_A10_PIT_DEFAULT_CLOCK;
230         s->interval[i] = 0;
231         s->count[i] = 0;
232         ptimer_transaction_begin(s->timer[i]);
233         ptimer_stop(s->timer[i]);
234         a10_pit_set_freq(s, i);
235         ptimer_transaction_commit(s->timer[i]);
236     }
237     s->watch_dog_mode = 0;
238     s->watch_dog_control = 0;
239     s->count_lo = 0;
240     s->count_hi = 0;
241     s->count_ctl = 0;
242 }
243 
244 static void a10_pit_timer_cb(void *opaque)
245 {
246     AwA10TimerContext *tc = opaque;
247     AwA10PITState *s = tc->container;
248     uint8_t i = tc->index;
249 
250     if (s->control[i] & AW_A10_PIT_TIMER_EN) {
251         s->irq_status |= 1 << i;
252         if (s->control[i] & AW_A10_PIT_TIMER_MODE) {
253             ptimer_stop(s->timer[i]);
254             s->control[i] &= ~AW_A10_PIT_TIMER_EN;
255         }
256         a10_pit_update_irq(s);
257     }
258 }
259 
260 static void a10_pit_init(Object *obj)
261 {
262     AwA10PITState *s = AW_A10_PIT(obj);
263     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
264     uint8_t i;
265 
266     for (i = 0; i < AW_A10_PIT_TIMER_NR; i++) {
267         sysbus_init_irq(sbd, &s->irq[i]);
268     }
269     memory_region_init_io(&s->iomem, OBJECT(s), &a10_pit_ops, s,
270                           TYPE_AW_A10_PIT, 0x400);
271     sysbus_init_mmio(sbd, &s->iomem);
272 
273     for (i = 0; i < AW_A10_PIT_TIMER_NR; i++) {
274         AwA10TimerContext *tc = &s->timer_context[i];
275 
276         tc->container = s;
277         tc->index = i;
278         s->timer[i] = ptimer_init(a10_pit_timer_cb, tc, PTIMER_POLICY_LEGACY);
279     }
280 }
281 
282 static void a10_pit_finalize(Object *obj)
283 {
284     AwA10PITState *s = AW_A10_PIT(obj);
285     int i;
286 
287     for (i = 0; i < AW_A10_PIT_TIMER_NR; i++) {
288         ptimer_free(s->timer[i]);
289     }
290 }
291 
292 static void a10_pit_class_init(ObjectClass *klass, void *data)
293 {
294     DeviceClass *dc = DEVICE_CLASS(klass);
295 
296     dc->reset = a10_pit_reset;
297     device_class_set_props(dc, a10_pit_properties);
298     dc->desc = "allwinner a10 timer";
299     dc->vmsd = &vmstate_a10_pit;
300 }
301 
302 static const TypeInfo a10_pit_info = {
303     .name = TYPE_AW_A10_PIT,
304     .parent = TYPE_SYS_BUS_DEVICE,
305     .instance_size = sizeof(AwA10PITState),
306     .instance_init = a10_pit_init,
307     .instance_finalize = a10_pit_finalize,
308     .class_init = a10_pit_class_init,
309 };
310 
311 static void a10_register_types(void)
312 {
313     type_register_static(&a10_pit_info);
314 }
315 
316 type_init(a10_register_types);
317