xref: /openbmc/qemu/hw/timer/allwinner-a10-pit.c (revision 4a66d3bf)
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 "hw/sysbus.h"
19 #include "sysemu/sysemu.h"
20 #include "hw/timer/allwinner-a10-pit.h"
21 
22 static void a10_pit_update_irq(AwA10PITState *s)
23 {
24     int i;
25 
26     for (i = 0; i < AW_A10_PIT_TIMER_NR; i++) {
27         qemu_set_irq(s->irq[i], !!(s->irq_status & s->irq_enable & (1 << i)));
28     }
29 }
30 
31 static uint64_t a10_pit_read(void *opaque, hwaddr offset, unsigned size)
32 {
33     AwA10PITState *s = AW_A10_PIT(opaque);
34     uint8_t index;
35 
36     switch (offset) {
37     case AW_A10_PIT_TIMER_IRQ_EN:
38         return s->irq_enable;
39     case AW_A10_PIT_TIMER_IRQ_ST:
40         return s->irq_status;
41     case AW_A10_PIT_TIMER_BASE ... AW_A10_PIT_TIMER_BASE_END:
42         index = offset & 0xf0;
43         index >>= 4;
44         index -= 1;
45         switch (offset & 0x0f) {
46         case AW_A10_PIT_TIMER_CONTROL:
47             return s->control[index];
48         case AW_A10_PIT_TIMER_INTERVAL:
49             return s->interval[index];
50         case AW_A10_PIT_TIMER_COUNT:
51             s->count[index] = ptimer_get_count(s->timer[index]);
52             return s->count[index];
53         default:
54             qemu_log_mask(LOG_GUEST_ERROR,
55                           "%s: Bad offset 0x%x\n",  __func__, (int)offset);
56             break;
57         }
58     case AW_A10_PIT_WDOG_CONTROL:
59         break;
60     case AW_A10_PIT_WDOG_MODE:
61         break;
62     case AW_A10_PIT_COUNT_LO:
63         return s->count_lo;
64     case AW_A10_PIT_COUNT_HI:
65         return s->count_hi;
66     case AW_A10_PIT_COUNT_CTL:
67         return s->count_ctl;
68     default:
69         qemu_log_mask(LOG_GUEST_ERROR,
70                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
71         break;
72     }
73 
74     return 0;
75 }
76 
77 static void a10_pit_set_freq(AwA10PITState *s, int index)
78 {
79     uint32_t prescaler, source, source_freq;
80 
81     prescaler = 1 << extract32(s->control[index], 4, 3);
82     source = extract32(s->control[index], 2, 2);
83     source_freq = s->clk_freq[source];
84 
85     if (source_freq) {
86         ptimer_set_freq(s->timer[index], source_freq / prescaler);
87     } else {
88         qemu_log_mask(LOG_GUEST_ERROR, "%s: Invalid clock source %u\n",
89                       __func__, source);
90     }
91 }
92 
93 static void a10_pit_write(void *opaque, hwaddr offset, uint64_t value,
94                             unsigned size)
95 {
96      AwA10PITState *s = AW_A10_PIT(opaque);
97      uint8_t index;
98 
99     switch (offset) {
100     case AW_A10_PIT_TIMER_IRQ_EN:
101         s->irq_enable = value;
102         a10_pit_update_irq(s);
103         break;
104     case AW_A10_PIT_TIMER_IRQ_ST:
105         s->irq_status &= ~value;
106         a10_pit_update_irq(s);
107         break;
108     case AW_A10_PIT_TIMER_BASE ... AW_A10_PIT_TIMER_BASE_END:
109         index = offset & 0xf0;
110         index >>= 4;
111         index -= 1;
112         switch (offset & 0x0f) {
113         case AW_A10_PIT_TIMER_CONTROL:
114             s->control[index] = value;
115             a10_pit_set_freq(s, index);
116             if (s->control[index] & AW_A10_PIT_TIMER_RELOAD) {
117                 ptimer_set_count(s->timer[index], s->interval[index]);
118             }
119             if (s->control[index] & AW_A10_PIT_TIMER_EN) {
120                 int oneshot = 0;
121                 if (s->control[index] & AW_A10_PIT_TIMER_MODE) {
122                     oneshot = 1;
123                 }
124                 ptimer_run(s->timer[index], oneshot);
125             } else {
126                 ptimer_stop(s->timer[index]);
127             }
128             break;
129         case AW_A10_PIT_TIMER_INTERVAL:
130             s->interval[index] = value;
131             ptimer_set_limit(s->timer[index], s->interval[index], 1);
132             break;
133         case AW_A10_PIT_TIMER_COUNT:
134             s->count[index] = value;
135             break;
136         default:
137             qemu_log_mask(LOG_GUEST_ERROR,
138                           "%s: Bad offset 0x%x\n",  __func__, (int)offset);
139         }
140         break;
141     case AW_A10_PIT_WDOG_CONTROL:
142         s->watch_dog_control = value;
143         break;
144     case AW_A10_PIT_WDOG_MODE:
145         s->watch_dog_mode = value;
146         break;
147     case AW_A10_PIT_COUNT_LO:
148         s->count_lo = value;
149         break;
150     case AW_A10_PIT_COUNT_HI:
151         s->count_hi = value;
152         break;
153     case AW_A10_PIT_COUNT_CTL:
154         s->count_ctl = value;
155         if (s->count_ctl & AW_A10_PIT_COUNT_RL_EN) {
156             uint64_t  tmp_count = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
157 
158             s->count_lo = tmp_count;
159             s->count_hi = tmp_count >> 32;
160             s->count_ctl &= ~AW_A10_PIT_COUNT_RL_EN;
161         }
162         if (s->count_ctl & AW_A10_PIT_COUNT_CLR_EN) {
163             s->count_lo = 0;
164             s->count_hi = 0;
165             s->count_ctl &= ~AW_A10_PIT_COUNT_CLR_EN;
166         }
167         break;
168     default:
169         qemu_log_mask(LOG_GUEST_ERROR,
170                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
171         break;
172     }
173 }
174 
175 static const MemoryRegionOps a10_pit_ops = {
176     .read = a10_pit_read,
177     .write = a10_pit_write,
178     .endianness = DEVICE_NATIVE_ENDIAN,
179 };
180 
181 static Property a10_pit_properties[] = {
182     DEFINE_PROP_UINT32("clk0-freq", AwA10PITState, clk_freq[0], 0),
183     DEFINE_PROP_UINT32("clk1-freq", AwA10PITState, clk_freq[1], 0),
184     DEFINE_PROP_UINT32("clk2-freq", AwA10PITState, clk_freq[2], 0),
185     DEFINE_PROP_UINT32("clk3-freq", AwA10PITState, clk_freq[3], 0),
186     DEFINE_PROP_END_OF_LIST(),
187 };
188 
189 static const VMStateDescription vmstate_a10_pit = {
190     .name = "a10.pit",
191     .version_id = 1,
192     .minimum_version_id = 1,
193     .minimum_version_id_old = 1,
194     .fields = (VMStateField[]) {
195         VMSTATE_UINT32(irq_enable, AwA10PITState),
196         VMSTATE_UINT32(irq_status, AwA10PITState),
197         VMSTATE_UINT32_ARRAY(control, AwA10PITState, AW_A10_PIT_TIMER_NR),
198         VMSTATE_UINT32_ARRAY(interval, AwA10PITState, AW_A10_PIT_TIMER_NR),
199         VMSTATE_UINT32_ARRAY(count, AwA10PITState, AW_A10_PIT_TIMER_NR),
200         VMSTATE_UINT32(watch_dog_mode, AwA10PITState),
201         VMSTATE_UINT32(watch_dog_control, AwA10PITState),
202         VMSTATE_UINT32(count_lo, AwA10PITState),
203         VMSTATE_UINT32(count_hi, AwA10PITState),
204         VMSTATE_UINT32(count_ctl, AwA10PITState),
205         VMSTATE_PTIMER_ARRAY(timer, AwA10PITState, AW_A10_PIT_TIMER_NR),
206         VMSTATE_END_OF_LIST()
207     }
208 };
209 
210 static void a10_pit_reset(DeviceState *dev)
211 {
212     AwA10PITState *s = AW_A10_PIT(dev);
213     uint8_t i;
214 
215     s->irq_enable = 0;
216     s->irq_status = 0;
217     a10_pit_update_irq(s);
218 
219     for (i = 0; i < 6; i++) {
220         s->control[i] = AW_A10_PIT_DEFAULT_CLOCK;
221         s->interval[i] = 0;
222         s->count[i] = 0;
223         ptimer_stop(s->timer[i]);
224         a10_pit_set_freq(s, i);
225     }
226     s->watch_dog_mode = 0;
227     s->watch_dog_control = 0;
228     s->count_lo = 0;
229     s->count_hi = 0;
230     s->count_ctl = 0;
231 }
232 
233 static void a10_pit_timer_cb(void *opaque)
234 {
235     AwA10TimerContext *tc = opaque;
236     AwA10PITState *s = tc->container;
237     uint8_t i = tc->index;
238 
239     if (s->control[i] & AW_A10_PIT_TIMER_EN) {
240         s->irq_status |= 1 << i;
241         if (s->control[i] & AW_A10_PIT_TIMER_MODE) {
242             ptimer_stop(s->timer[i]);
243             s->control[i] &= ~AW_A10_PIT_TIMER_EN;
244         }
245         a10_pit_update_irq(s);
246     }
247 }
248 
249 static void a10_pit_init(Object *obj)
250 {
251     AwA10PITState *s = AW_A10_PIT(obj);
252     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
253     QEMUBH * bh[AW_A10_PIT_TIMER_NR];
254     uint8_t i;
255 
256     for (i = 0; i < AW_A10_PIT_TIMER_NR; i++) {
257         sysbus_init_irq(sbd, &s->irq[i]);
258     }
259     memory_region_init_io(&s->iomem, OBJECT(s), &a10_pit_ops, s,
260                           TYPE_AW_A10_PIT, 0x400);
261     sysbus_init_mmio(sbd, &s->iomem);
262 
263     for (i = 0; i < AW_A10_PIT_TIMER_NR; i++) {
264         AwA10TimerContext *tc = &s->timer_context[i];
265 
266         tc->container = s;
267         tc->index = i;
268         bh[i] = qemu_bh_new(a10_pit_timer_cb, tc);
269         s->timer[i] = ptimer_init(bh[i]);
270     }
271 }
272 
273 static void a10_pit_class_init(ObjectClass *klass, void *data)
274 {
275     DeviceClass *dc = DEVICE_CLASS(klass);
276 
277     dc->reset = a10_pit_reset;
278     dc->props = a10_pit_properties;
279     dc->desc = "allwinner a10 timer";
280     dc->vmsd = &vmstate_a10_pit;
281 }
282 
283 static const TypeInfo a10_pit_info = {
284     .name = TYPE_AW_A10_PIT,
285     .parent = TYPE_SYS_BUS_DEVICE,
286     .instance_size = sizeof(AwA10PITState),
287     .instance_init = a10_pit_init,
288     .class_init = a10_pit_class_init,
289 };
290 
291 static void a10_register_types(void)
292 {
293     type_register_static(&a10_pit_info);
294 }
295 
296 type_init(a10_register_types);
297