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24#include "qemu/osdep.h"
25#include "hw/hw.h"
26#include "hw/sysbus.h"
27#include "trace.h"
28#include "qemu/timer.h"
29#include "hw/ptimer.h"
30#include "qemu/error-report.h"
31#include "qemu/main-loop.h"
32
33#define DEFAULT_FREQUENCY (50*1000000)
34
35enum {
36 R_SR = 0,
37 R_CR,
38 R_PERIOD,
39 R_SNAPSHOT,
40 R_MAX
41};
42
43enum {
44 SR_TO = (1 << 0),
45 SR_RUN = (1 << 1),
46};
47
48enum {
49 CR_ITO = (1 << 0),
50 CR_CONT = (1 << 1),
51 CR_START = (1 << 2),
52 CR_STOP = (1 << 3),
53};
54
55#define TYPE_LM32_TIMER "lm32-timer"
56#define LM32_TIMER(obj) OBJECT_CHECK(LM32TimerState, (obj), TYPE_LM32_TIMER)
57
58struct LM32TimerState {
59 SysBusDevice parent_obj;
60
61 MemoryRegion iomem;
62
63 QEMUBH *bh;
64 ptimer_state *ptimer;
65
66 qemu_irq irq;
67 uint32_t freq_hz;
68
69 uint32_t regs[R_MAX];
70};
71typedef struct LM32TimerState LM32TimerState;
72
73static void timer_update_irq(LM32TimerState *s)
74{
75 int state = (s->regs[R_SR] & SR_TO) && (s->regs[R_CR] & CR_ITO);
76
77 trace_lm32_timer_irq_state(state);
78 qemu_set_irq(s->irq, state);
79}
80
81static uint64_t timer_read(void *opaque, hwaddr addr, unsigned size)
82{
83 LM32TimerState *s = opaque;
84 uint32_t r = 0;
85
86 addr >>= 2;
87 switch (addr) {
88 case R_SR:
89 case R_CR:
90 case R_PERIOD:
91 r = s->regs[addr];
92 break;
93 case R_SNAPSHOT:
94 r = (uint32_t)ptimer_get_count(s->ptimer);
95 break;
96 default:
97 error_report("lm32_timer: read access to unknown register 0x"
98 TARGET_FMT_plx, addr << 2);
99 break;
100 }
101
102 trace_lm32_timer_memory_read(addr << 2, r);
103 return r;
104}
105
106static void timer_write(void *opaque, hwaddr addr,
107 uint64_t value, unsigned size)
108{
109 LM32TimerState *s = opaque;
110
111 trace_lm32_timer_memory_write(addr, value);
112
113 addr >>= 2;
114 switch (addr) {
115 case R_SR:
116 s->regs[R_SR] &= ~SR_TO;
117 break;
118 case R_CR:
119 s->regs[R_CR] = value;
120 if (s->regs[R_CR] & CR_START) {
121 ptimer_run(s->ptimer, 1);
122 }
123 if (s->regs[R_CR] & CR_STOP) {
124 ptimer_stop(s->ptimer);
125 }
126 break;
127 case R_PERIOD:
128 s->regs[R_PERIOD] = value;
129 ptimer_set_count(s->ptimer, value);
130 break;
131 case R_SNAPSHOT:
132 error_report("lm32_timer: write access to read only register 0x"
133 TARGET_FMT_plx, addr << 2);
134 break;
135 default:
136 error_report("lm32_timer: write access to unknown register 0x"
137 TARGET_FMT_plx, addr << 2);
138 break;
139 }
140 timer_update_irq(s);
141}
142
143static const MemoryRegionOps timer_ops = {
144 .read = timer_read,
145 .write = timer_write,
146 .endianness = DEVICE_NATIVE_ENDIAN,
147 .valid = {
148 .min_access_size = 4,
149 .max_access_size = 4,
150 },
151};
152
153static void timer_hit(void *opaque)
154{
155 LM32TimerState *s = opaque;
156
157 trace_lm32_timer_hit();
158
159 s->regs[R_SR] |= SR_TO;
160
161 if (s->regs[R_CR] & CR_CONT) {
162 ptimer_set_count(s->ptimer, s->regs[R_PERIOD]);
163 ptimer_run(s->ptimer, 1);
164 }
165 timer_update_irq(s);
166}
167
168static void timer_reset(DeviceState *d)
169{
170 LM32TimerState *s = LM32_TIMER(d);
171 int i;
172
173 for (i = 0; i < R_MAX; i++) {
174 s->regs[i] = 0;
175 }
176 ptimer_stop(s->ptimer);
177}
178
179static void lm32_timer_init(Object *obj)
180{
181 LM32TimerState *s = LM32_TIMER(obj);
182 SysBusDevice *dev = SYS_BUS_DEVICE(obj);
183
184 sysbus_init_irq(dev, &s->irq);
185
186 s->bh = qemu_bh_new(timer_hit, s);
187 s->ptimer = ptimer_init(s->bh, PTIMER_POLICY_DEFAULT);
188
189 memory_region_init_io(&s->iomem, obj, &timer_ops, s,
190 "timer", R_MAX * 4);
191 sysbus_init_mmio(dev, &s->iomem);
192}
193
194static void lm32_timer_realize(DeviceState *dev, Error **errp)
195{
196 LM32TimerState *s = LM32_TIMER(dev);
197
198 ptimer_set_freq(s->ptimer, s->freq_hz);
199}
200
201static const VMStateDescription vmstate_lm32_timer = {
202 .name = "lm32-timer",
203 .version_id = 1,
204 .minimum_version_id = 1,
205 .fields = (VMStateField[]) {
206 VMSTATE_PTIMER(ptimer, LM32TimerState),
207 VMSTATE_UINT32(freq_hz, LM32TimerState),
208 VMSTATE_UINT32_ARRAY(regs, LM32TimerState, R_MAX),
209 VMSTATE_END_OF_LIST()
210 }
211};
212
213static Property lm32_timer_properties[] = {
214 DEFINE_PROP_UINT32("frequency", LM32TimerState, freq_hz, DEFAULT_FREQUENCY),
215 DEFINE_PROP_END_OF_LIST(),
216};
217
218static void lm32_timer_class_init(ObjectClass *klass, void *data)
219{
220 DeviceClass *dc = DEVICE_CLASS(klass);
221
222 dc->realize = lm32_timer_realize;
223 dc->reset = timer_reset;
224 dc->vmsd = &vmstate_lm32_timer;
225 dc->props = lm32_timer_properties;
226}
227
228static const TypeInfo lm32_timer_info = {
229 .name = TYPE_LM32_TIMER,
230 .parent = TYPE_SYS_BUS_DEVICE,
231 .instance_size = sizeof(LM32TimerState),
232 .instance_init = lm32_timer_init,
233 .class_init = lm32_timer_class_init,
234};
235
236static void lm32_timer_register_types(void)
237{
238 type_register_static(&lm32_timer_info);
239}
240
241type_init(lm32_timer_register_types)
242