Update version for v6.2.0-rc4 release
[qemu.git] / hw / timer / altera_timer.c
1 /*
2 * QEMU model of the Altera timer.
3 *
4 * Copyright (c) 2012 Chris Wulff <crwulff@gmail.com>
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see
18 * <http://www.gnu.org/licenses/lgpl-2.1.html>
19 */
20
21 #include "qemu/osdep.h"
22 #include "qemu/module.h"
23 #include "qapi/error.h"
24
25 #include "hw/sysbus.h"
26 #include "hw/irq.h"
27 #include "hw/ptimer.h"
28 #include "hw/qdev-properties.h"
29 #include "qom/object.h"
30
31 #define R_STATUS 0
32 #define R_CONTROL 1
33 #define R_PERIODL 2
34 #define R_PERIODH 3
35 #define R_SNAPL 4
36 #define R_SNAPH 5
37 #define R_MAX 6
38
39 #define STATUS_TO 0x0001
40 #define STATUS_RUN 0x0002
41
42 #define CONTROL_ITO 0x0001
43 #define CONTROL_CONT 0x0002
44 #define CONTROL_START 0x0004
45 #define CONTROL_STOP 0x0008
46
47 #define TYPE_ALTERA_TIMER "ALTR.timer"
48 OBJECT_DECLARE_SIMPLE_TYPE(AlteraTimer, ALTERA_TIMER)
49
50 struct AlteraTimer {
51 SysBusDevice busdev;
52 MemoryRegion mmio;
53 qemu_irq irq;
54 uint32_t freq_hz;
55 ptimer_state *ptimer;
56 uint32_t regs[R_MAX];
57 };
58
59 static int timer_irq_state(AlteraTimer *t)
60 {
61 bool irq = (t->regs[R_STATUS] & STATUS_TO) &&
62 (t->regs[R_CONTROL] & CONTROL_ITO);
63 return irq;
64 }
65
66 static uint64_t timer_read(void *opaque, hwaddr addr,
67 unsigned int size)
68 {
69 AlteraTimer *t = opaque;
70 uint64_t r = 0;
71
72 addr >>= 2;
73
74 switch (addr) {
75 case R_CONTROL:
76 r = t->regs[R_CONTROL] & (CONTROL_ITO | CONTROL_CONT);
77 break;
78
79 default:
80 if (addr < ARRAY_SIZE(t->regs)) {
81 r = t->regs[addr];
82 }
83 break;
84 }
85
86 return r;
87 }
88
89 static void timer_write(void *opaque, hwaddr addr,
90 uint64_t value, unsigned int size)
91 {
92 AlteraTimer *t = opaque;
93 uint64_t tvalue;
94 uint32_t count = 0;
95 int irqState = timer_irq_state(t);
96
97 addr >>= 2;
98
99 switch (addr) {
100 case R_STATUS:
101 /* The timeout bit is cleared by writing the status register. */
102 t->regs[R_STATUS] &= ~STATUS_TO;
103 break;
104
105 case R_CONTROL:
106 ptimer_transaction_begin(t->ptimer);
107 t->regs[R_CONTROL] = value & (CONTROL_ITO | CONTROL_CONT);
108 if ((value & CONTROL_START) &&
109 !(t->regs[R_STATUS] & STATUS_RUN)) {
110 ptimer_run(t->ptimer, 1);
111 t->regs[R_STATUS] |= STATUS_RUN;
112 }
113 if ((value & CONTROL_STOP) && (t->regs[R_STATUS] & STATUS_RUN)) {
114 ptimer_stop(t->ptimer);
115 t->regs[R_STATUS] &= ~STATUS_RUN;
116 }
117 ptimer_transaction_commit(t->ptimer);
118 break;
119
120 case R_PERIODL:
121 case R_PERIODH:
122 ptimer_transaction_begin(t->ptimer);
123 t->regs[addr] = value & 0xFFFF;
124 if (t->regs[R_STATUS] & STATUS_RUN) {
125 ptimer_stop(t->ptimer);
126 t->regs[R_STATUS] &= ~STATUS_RUN;
127 }
128 tvalue = (t->regs[R_PERIODH] << 16) | t->regs[R_PERIODL];
129 ptimer_set_limit(t->ptimer, tvalue + 1, 1);
130 ptimer_transaction_commit(t->ptimer);
131 break;
132
133 case R_SNAPL:
134 case R_SNAPH:
135 count = ptimer_get_count(t->ptimer);
136 t->regs[R_SNAPL] = count & 0xFFFF;
137 t->regs[R_SNAPH] = count >> 16;
138 break;
139
140 default:
141 break;
142 }
143
144 if (irqState != timer_irq_state(t)) {
145 qemu_set_irq(t->irq, timer_irq_state(t));
146 }
147 }
148
149 static const MemoryRegionOps timer_ops = {
150 .read = timer_read,
151 .write = timer_write,
152 .endianness = DEVICE_NATIVE_ENDIAN,
153 .valid = {
154 .min_access_size = 1,
155 .max_access_size = 4
156 }
157 };
158
159 static void timer_hit(void *opaque)
160 {
161 AlteraTimer *t = opaque;
162 const uint64_t tvalue = (t->regs[R_PERIODH] << 16) | t->regs[R_PERIODL];
163
164 t->regs[R_STATUS] |= STATUS_TO;
165
166 ptimer_set_limit(t->ptimer, tvalue + 1, 1);
167
168 if (!(t->regs[R_CONTROL] & CONTROL_CONT)) {
169 t->regs[R_STATUS] &= ~STATUS_RUN;
170 ptimer_set_count(t->ptimer, tvalue);
171 } else {
172 ptimer_run(t->ptimer, 1);
173 }
174
175 qemu_set_irq(t->irq, timer_irq_state(t));
176 }
177
178 static void altera_timer_realize(DeviceState *dev, Error **errp)
179 {
180 AlteraTimer *t = ALTERA_TIMER(dev);
181 SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
182
183 if (t->freq_hz == 0) {
184 error_setg(errp, "\"clock-frequency\" property must be provided.");
185 return;
186 }
187
188 t->ptimer = ptimer_init(timer_hit, t, PTIMER_POLICY_DEFAULT);
189 ptimer_transaction_begin(t->ptimer);
190 ptimer_set_freq(t->ptimer, t->freq_hz);
191 ptimer_transaction_commit(t->ptimer);
192
193 memory_region_init_io(&t->mmio, OBJECT(t), &timer_ops, t,
194 TYPE_ALTERA_TIMER, R_MAX * sizeof(uint32_t));
195 sysbus_init_mmio(sbd, &t->mmio);
196 }
197
198 static void altera_timer_init(Object *obj)
199 {
200 AlteraTimer *t = ALTERA_TIMER(obj);
201 SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
202
203 sysbus_init_irq(sbd, &t->irq);
204 }
205
206 static void altera_timer_reset(DeviceState *dev)
207 {
208 AlteraTimer *t = ALTERA_TIMER(dev);
209
210 ptimer_transaction_begin(t->ptimer);
211 ptimer_stop(t->ptimer);
212 ptimer_set_limit(t->ptimer, 0xffffffff, 1);
213 ptimer_transaction_commit(t->ptimer);
214 memset(t->regs, 0, sizeof(t->regs));
215 }
216
217 static Property altera_timer_properties[] = {
218 DEFINE_PROP_UINT32("clock-frequency", AlteraTimer, freq_hz, 0),
219 DEFINE_PROP_END_OF_LIST(),
220 };
221
222 static void altera_timer_class_init(ObjectClass *klass, void *data)
223 {
224 DeviceClass *dc = DEVICE_CLASS(klass);
225
226 dc->realize = altera_timer_realize;
227 device_class_set_props(dc, altera_timer_properties);
228 dc->reset = altera_timer_reset;
229 }
230
231 static const TypeInfo altera_timer_info = {
232 .name = TYPE_ALTERA_TIMER,
233 .parent = TYPE_SYS_BUS_DEVICE,
234 .instance_size = sizeof(AlteraTimer),
235 .instance_init = altera_timer_init,
236 .class_init = altera_timer_class_init,
237 };
238
239 static void altera_timer_register(void)
240 {
241 type_register_static(&altera_timer_info);
242 }
243
244 type_init(altera_timer_register)