1 /*
2 * QEMU ETRAX Timers
3 *
4 * Copyright (c) 2007 Edgar E. Iglesias, Axis Communications AB.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
24 #include "qemu/osdep.h"
25 #include "hw/sysbus.h"
26 #include "sysemu/sysemu.h"
27 #include "qemu/timer.h"
28 #include "hw/ptimer.h"
29
30 #define D(x)
31
32 #define RW_TMR0_DIV 0x00
33 #define R_TMR0_DATA 0x04
34 #define RW_TMR0_CTRL 0x08
35 #define RW_TMR1_DIV 0x10
36 #define R_TMR1_DATA 0x14
37 #define RW_TMR1_CTRL 0x18
38 #define R_TIME 0x38
39 #define RW_WD_CTRL 0x40
40 #define R_WD_STAT 0x44
41 #define RW_INTR_MASK 0x48
42 #define RW_ACK_INTR 0x4c
43 #define R_INTR 0x50
44 #define R_MASKED_INTR 0x54
45
46 #define TYPE_ETRAX_FS_TIMER "etraxfs,timer"
47 #define ETRAX_TIMER(obj) \
48 OBJECT_CHECK(ETRAXTimerState, (obj), TYPE_ETRAX_FS_TIMER)
49
50 typedef struct ETRAXTimerState {
51 SysBusDevice parent_obj;
52
53 MemoryRegion mmio;
54 qemu_irq irq;
55 qemu_irq nmi;
56
57 QEMUBH *bh_t0;
58 QEMUBH *bh_t1;
59 QEMUBH *bh_wd;
60 ptimer_state *ptimer_t0;
61 ptimer_state *ptimer_t1;
62 ptimer_state *ptimer_wd;
63
64 int wd_hits;
65
66 /* Control registers. */
67 uint32_t rw_tmr0_div;
68 uint32_t r_tmr0_data;
69 uint32_t rw_tmr0_ctrl;
70
71 uint32_t rw_tmr1_div;
72 uint32_t r_tmr1_data;
73 uint32_t rw_tmr1_ctrl;
74
75 uint32_t rw_wd_ctrl;
76
77 uint32_t rw_intr_mask;
78 uint32_t rw_ack_intr;
79 uint32_t r_intr;
80 uint32_t r_masked_intr;
81 } ETRAXTimerState;
82
83 static uint64_t
timer_read(void * opaque,hwaddr addr,unsigned int size)84 timer_read(void *opaque, hwaddr addr, unsigned int size)
85 {
86 ETRAXTimerState *t = opaque;
87 uint32_t r = 0;
88
89 switch (addr) {
90 case R_TMR0_DATA:
91 r = ptimer_get_count(t->ptimer_t0);
92 break;
93 case R_TMR1_DATA:
94 r = ptimer_get_count(t->ptimer_t1);
95 break;
96 case R_TIME:
97 r = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) / 10;
98 break;
99 case RW_INTR_MASK:
100 r = t->rw_intr_mask;
101 break;
102 case R_MASKED_INTR:
103 r = t->r_intr & t->rw_intr_mask;
104 break;
105 default:
106 D(printf ("%s %x\n", __func__, addr));
107 break;
108 }
109 return r;
110 }
111
update_ctrl(ETRAXTimerState * t,int tnum)112 static void update_ctrl(ETRAXTimerState *t, int tnum)
113 {
114 unsigned int op;
115 unsigned int freq;
116 unsigned int freq_hz;
117 unsigned int div;
118 uint32_t ctrl;
119
120 ptimer_state *timer;
121
122 if (tnum == 0) {
123 ctrl = t->rw_tmr0_ctrl;
124 div = t->rw_tmr0_div;
125 timer = t->ptimer_t0;
126 } else {
127 ctrl = t->rw_tmr1_ctrl;
128 div = t->rw_tmr1_div;
129 timer = t->ptimer_t1;
130 }
131
132
133 op = ctrl & 3;
134 freq = ctrl >> 2;
135 freq_hz = 32000000;
136
137 switch (freq)
138 {
139 case 0:
140 case 1:
141 D(printf ("extern or disabled timer clock?\n"));
142 break;
143 case 4: freq_hz = 29493000; break;
144 case 5: freq_hz = 32000000; break;
145 case 6: freq_hz = 32768000; break;
146 case 7: freq_hz = 100000000; break;
147 default:
148 abort();
149 break;
150 }
151
152 D(printf ("freq_hz=%d div=%d\n", freq_hz, div));
153 ptimer_set_freq(timer, freq_hz);
154 ptimer_set_limit(timer, div, 0);
155
156 switch (op)
157 {
158 case 0:
159 /* Load. */
160 ptimer_set_limit(timer, div, 1);
161 break;
162 case 1:
163 /* Hold. */
164 ptimer_stop(timer);
165 break;
166 case 2:
167 /* Run. */
168 ptimer_run(timer, 0);
169 break;
170 default:
171 abort();
172 break;
173 }
174 }
175
timer_update_irq(ETRAXTimerState * t)176 static void timer_update_irq(ETRAXTimerState *t)
177 {
178 t->r_intr &= ~(t->rw_ack_intr);
179 t->r_masked_intr = t->r_intr & t->rw_intr_mask;
180
181 D(printf("%s: masked_intr=%x\n", __func__, t->r_masked_intr));
182 qemu_set_irq(t->irq, !!t->r_masked_intr);
183 }
184
timer0_hit(void * opaque)185 static void timer0_hit(void *opaque)
186 {
187 ETRAXTimerState *t = opaque;
188 t->r_intr |= 1;
189 timer_update_irq(t);
190 }
191
timer1_hit(void * opaque)192 static void timer1_hit(void *opaque)
193 {
194 ETRAXTimerState *t = opaque;
195 t->r_intr |= 2;
196 timer_update_irq(t);
197 }
198
watchdog_hit(void * opaque)199 static void watchdog_hit(void *opaque)
200 {
201 ETRAXTimerState *t = opaque;
202 if (t->wd_hits == 0) {
203 /* real hw gives a single tick before reseting but we are
204 a bit friendlier to compensate for our slower execution. */
205 ptimer_set_count(t->ptimer_wd, 10);
206 ptimer_run(t->ptimer_wd, 1);
207 qemu_irq_raise(t->nmi);
208 }
209 else
210 qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
211
212 t->wd_hits++;
213 }
214
timer_watchdog_update(ETRAXTimerState * t,uint32_t value)215 static inline void timer_watchdog_update(ETRAXTimerState *t, uint32_t value)
216 {
217 unsigned int wd_en = t->rw_wd_ctrl & (1 << 8);
218 unsigned int wd_key = t->rw_wd_ctrl >> 9;
219 unsigned int wd_cnt = t->rw_wd_ctrl & 511;
220 unsigned int new_key = value >> 9 & ((1 << 7) - 1);
221 unsigned int new_cmd = (value >> 8) & 1;
222
223 /* If the watchdog is enabled, they written key must match the
224 complement of the previous. */
225 wd_key = ~wd_key & ((1 << 7) - 1);
226
227 if (wd_en && wd_key != new_key)
228 return;
229
230 D(printf("en=%d new_key=%x oldkey=%x cmd=%d cnt=%d\n",
231 wd_en, new_key, wd_key, new_cmd, wd_cnt));
232
233 if (t->wd_hits)
234 qemu_irq_lower(t->nmi);
235
236 t->wd_hits = 0;
237
238 ptimer_set_freq(t->ptimer_wd, 760);
239 if (wd_cnt == 0)
240 wd_cnt = 256;
241 ptimer_set_count(t->ptimer_wd, wd_cnt);
242 if (new_cmd)
243 ptimer_run(t->ptimer_wd, 1);
244 else
245 ptimer_stop(t->ptimer_wd);
246
247 t->rw_wd_ctrl = value;
248 }
249
250 static void
timer_write(void * opaque,hwaddr addr,uint64_t val64,unsigned int size)251 timer_write(void *opaque, hwaddr addr,
252 uint64_t val64, unsigned int size)
253 {
254 ETRAXTimerState *t = opaque;
255 uint32_t value = val64;
256
257 switch (addr)
258 {
259 case RW_TMR0_DIV:
260 t->rw_tmr0_div = value;
261 break;
262 case RW_TMR0_CTRL:
263 D(printf ("RW_TMR0_CTRL=%x\n", value));
264 t->rw_tmr0_ctrl = value;
265 update_ctrl(t, 0);
266 break;
267 case RW_TMR1_DIV:
268 t->rw_tmr1_div = value;
269 break;
270 case RW_TMR1_CTRL:
271 D(printf ("RW_TMR1_CTRL=%x\n", value));
272 t->rw_tmr1_ctrl = value;
273 update_ctrl(t, 1);
274 break;
275 case RW_INTR_MASK:
276 D(printf ("RW_INTR_MASK=%x\n", value));
277 t->rw_intr_mask = value;
278 timer_update_irq(t);
279 break;
280 case RW_WD_CTRL:
281 timer_watchdog_update(t, value);
282 break;
283 case RW_ACK_INTR:
284 t->rw_ack_intr = value;
285 timer_update_irq(t);
286 t->rw_ack_intr = 0;
287 break;
288 default:
289 printf ("%s " TARGET_FMT_plx " %x\n",
290 __func__, addr, value);
291 break;
292 }
293 }
294
295 static const MemoryRegionOps timer_ops = {
296 .read = timer_read,
297 .write = timer_write,
298 .endianness = DEVICE_LITTLE_ENDIAN,
299 .valid = {
300 .min_access_size = 4,
301 .max_access_size = 4
302 }
303 };
304
etraxfs_timer_reset(void * opaque)305 static void etraxfs_timer_reset(void *opaque)
306 {
307 ETRAXTimerState *t = opaque;
308
309 ptimer_stop(t->ptimer_t0);
310 ptimer_stop(t->ptimer_t1);
311 ptimer_stop(t->ptimer_wd);
312 t->rw_wd_ctrl = 0;
313 t->r_intr = 0;
314 t->rw_intr_mask = 0;
315 qemu_irq_lower(t->irq);
316 }
317
etraxfs_timer_init(SysBusDevice * dev)318 static int etraxfs_timer_init(SysBusDevice *dev)
319 {
320 ETRAXTimerState *t = ETRAX_TIMER(dev);
321
322 t->bh_t0 = qemu_bh_new(timer0_hit, t);
323 t->bh_t1 = qemu_bh_new(timer1_hit, t);
324 t->bh_wd = qemu_bh_new(watchdog_hit, t);
325 t->ptimer_t0 = ptimer_init(t->bh_t0, PTIMER_POLICY_DEFAULT);
326 t->ptimer_t1 = ptimer_init(t->bh_t1, PTIMER_POLICY_DEFAULT);
327 t->ptimer_wd = ptimer_init(t->bh_wd, PTIMER_POLICY_DEFAULT);
328
329 sysbus_init_irq(dev, &t->irq);
330 sysbus_init_irq(dev, &t->nmi);
331
332 memory_region_init_io(&t->mmio, OBJECT(t), &timer_ops, t,
333 "etraxfs-timer", 0x5c);
334 sysbus_init_mmio(dev, &t->mmio);
335 qemu_register_reset(etraxfs_timer_reset, t);
336 return 0;
337 }
338
etraxfs_timer_class_init(ObjectClass * klass,void * data)339 static void etraxfs_timer_class_init(ObjectClass *klass, void *data)
340 {
341 SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
342
343 sdc->init = etraxfs_timer_init;
344 }
345
346 static const TypeInfo etraxfs_timer_info = {
347 .name = TYPE_ETRAX_FS_TIMER,
348 .parent = TYPE_SYS_BUS_DEVICE,
349 .instance_size = sizeof(ETRAXTimerState),
350 .class_init = etraxfs_timer_class_init,
351 };
352
etraxfs_timer_register_types(void)353 static void etraxfs_timer_register_types(void)
354 {
355 type_register_static(&etraxfs_timer_info);
356 }
357
358 type_init(etraxfs_timer_register_types)
359