xref: /qemu/hw/watchdog/wdt_aspeed.c (revision 513823e7521a09ed7ad1e32e6454bac3b2cbf52d)
1 /*
2  * ASPEED Watchdog Controller
3  *
4  * Copyright (C) 2016-2017 IBM Corp.
5  *
6  * This code is licensed under the GPL version 2 or later. See the
7  * COPYING file in the top-level directory.
8  */
9 
10 #include "qemu/osdep.h"
11 
12 #include "qapi/error.h"
13 #include "qemu/log.h"
14 #include "qemu/module.h"
15 #include "qemu/timer.h"
16 #include "system/watchdog.h"
17 #include "hw/qdev-properties.h"
18 #include "hw/sysbus.h"
19 #include "hw/watchdog/wdt_aspeed.h"
20 #include "migration/vmstate.h"
21 #include "trace.h"
22 
23 #define WDT_STATUS                      (0x00 / 4)
24 #define WDT_RELOAD_VALUE                (0x04 / 4)
25 #define WDT_RESTART                     (0x08 / 4)
26 #define WDT_CTRL                        (0x0C / 4)
27 #define   WDT_CTRL_RESET_MODE_SOC       (0x00 << 5)
28 #define   WDT_CTRL_RESET_MODE_FULL_CHIP (0x01 << 5)
29 #define   WDT_CTRL_1MHZ_CLK             BIT(4)
30 #define   WDT_CTRL_WDT_EXT              BIT(3)
31 #define   WDT_CTRL_WDT_INTR             BIT(2)
32 #define   WDT_CTRL_RESET_SYSTEM         BIT(1)
33 #define   WDT_CTRL_ENABLE               BIT(0)
34 #define WDT_RESET_WIDTH                 (0x18 / 4)
35 #define   WDT_RESET_WIDTH_ACTIVE_HIGH   BIT(31)
36 #define     WDT_POLARITY_MASK           (0xFF << 24)
37 #define     WDT_ACTIVE_HIGH_MAGIC       (0xA5 << 24)
38 #define     WDT_ACTIVE_LOW_MAGIC        (0x5A << 24)
39 #define   WDT_RESET_WIDTH_PUSH_PULL     BIT(30)
40 #define     WDT_DRIVE_TYPE_MASK         (0xFF << 24)
41 #define     WDT_PUSH_PULL_MAGIC         (0xA8 << 24)
42 #define     WDT_OPEN_DRAIN_MAGIC        (0x8A << 24)
43 #define WDT_RESET_MASK1                 (0x1c / 4)
44 #define WDT_RESET_MASK2                 (0x20 / 4)
45 
46 #define WDT_SW_RESET_CTRL               (0x24 / 4)
47 #define WDT_SW_RESET_MASK1              (0x28 / 4)
48 #define WDT_SW_RESET_MASK2              (0x2c / 4)
49 
50 #define WDT_TIMEOUT_STATUS              (0x10 / 4)
51 #define WDT_TIMEOUT_CLEAR               (0x14 / 4)
52 
53 #define WDT_RESTART_MAGIC               0x4755
54 #define WDT_SW_RESET_ENABLE             0xAEEDF123
55 
56 #define AST2600_SCU_RESET_CONTROL1      (0x40 / 4)
57 #define SCU_RESET_CONTROL1              (0x04 / 4)
58 #define    SCU_RESET_SDRAM              BIT(0)
59 
60 static bool aspeed_wdt_is_soc_reset_mode(const AspeedWDTState *s)
61 {
62     uint32_t mode;
63 
64     mode = extract32(s->regs[WDT_CTRL], 5, 2);
65     return (mode == WDT_CTRL_RESET_MODE_SOC);
66 }
67 
68 static bool aspeed_wdt_is_enabled(const AspeedWDTState *s)
69 {
70     return s->regs[WDT_CTRL] & WDT_CTRL_ENABLE;
71 }
72 
73 static uint64_t aspeed_wdt_read(void *opaque, hwaddr offset, unsigned size)
74 {
75     AspeedWDTState *s = ASPEED_WDT(opaque);
76 
77     trace_aspeed_wdt_read(offset, size);
78 
79     offset >>= 2;
80 
81     switch (offset) {
82     case WDT_STATUS:
83         return s->regs[WDT_STATUS];
84     case WDT_RELOAD_VALUE:
85         return s->regs[WDT_RELOAD_VALUE];
86     case WDT_RESTART:
87         qemu_log_mask(LOG_GUEST_ERROR,
88                       "%s: read from write-only reg at offset 0x%"
89                       HWADDR_PRIx "\n", __func__, offset);
90         return 0;
91     case WDT_CTRL:
92         return s->regs[WDT_CTRL];
93     case WDT_RESET_WIDTH:
94         return s->regs[WDT_RESET_WIDTH];
95     case WDT_RESET_MASK1:
96         return s->regs[WDT_RESET_MASK1];
97     case WDT_TIMEOUT_STATUS:
98     case WDT_TIMEOUT_CLEAR:
99     case WDT_RESET_MASK2:
100     case WDT_SW_RESET_CTRL:
101     case WDT_SW_RESET_MASK1:
102     case WDT_SW_RESET_MASK2:
103         qemu_log_mask(LOG_UNIMP,
104                       "%s: uninmplemented read at offset 0x%" HWADDR_PRIx "\n",
105                       __func__, offset);
106         return 0;
107     default:
108         qemu_log_mask(LOG_GUEST_ERROR,
109                       "%s: Out-of-bounds read at offset 0x%" HWADDR_PRIx "\n",
110                       __func__, offset);
111         return 0;
112     }
113 
114 }
115 
116 static void aspeed_wdt_reload(AspeedWDTState *s)
117 {
118     uint64_t reload;
119 
120     if (!(s->regs[WDT_CTRL] & WDT_CTRL_1MHZ_CLK)) {
121         reload = muldiv64(s->regs[WDT_RELOAD_VALUE], NANOSECONDS_PER_SECOND,
122                           s->pclk_freq);
123     } else {
124         reload = s->regs[WDT_RELOAD_VALUE] * 1000ULL;
125     }
126 
127     if (aspeed_wdt_is_enabled(s)) {
128         timer_mod(s->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + reload);
129     }
130 }
131 
132 static void aspeed_wdt_reload_1mhz(AspeedWDTState *s)
133 {
134     uint64_t reload = s->regs[WDT_RELOAD_VALUE] * 1000ULL;
135 
136     if (aspeed_wdt_is_enabled(s)) {
137         timer_mod(s->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + reload);
138     }
139 }
140 
141 static uint64_t aspeed_2400_sanitize_ctrl(uint64_t data)
142 {
143     return data & 0xffff;
144 }
145 
146 static uint64_t aspeed_2500_sanitize_ctrl(uint64_t data)
147 {
148     return (data & ~(0xfUL << 8)) | WDT_CTRL_1MHZ_CLK;
149 }
150 
151 static uint64_t aspeed_2600_sanitize_ctrl(uint64_t data)
152 {
153     return data & ~(0x7UL << 7);
154 }
155 
156 static void aspeed_wdt_write(void *opaque, hwaddr offset, uint64_t data,
157                              unsigned size)
158 {
159     AspeedWDTState *s = ASPEED_WDT(opaque);
160     AspeedWDTClass *awc = ASPEED_WDT_GET_CLASS(s);
161     bool enable;
162 
163     trace_aspeed_wdt_write(offset, size, data);
164 
165     offset >>= 2;
166 
167     switch (offset) {
168     case WDT_STATUS:
169         qemu_log_mask(LOG_GUEST_ERROR,
170                       "%s: write to read-only reg at offset 0x%"
171                       HWADDR_PRIx "\n", __func__, offset);
172         break;
173     case WDT_RELOAD_VALUE:
174         s->regs[WDT_RELOAD_VALUE] = data;
175         break;
176     case WDT_RESTART:
177         if ((data & 0xFFFF) == WDT_RESTART_MAGIC) {
178             s->regs[WDT_STATUS] = s->regs[WDT_RELOAD_VALUE];
179             awc->wdt_reload(s);
180         }
181         break;
182     case WDT_CTRL:
183         data = awc->sanitize_ctrl(data);
184         enable = data & WDT_CTRL_ENABLE;
185         if (enable && !aspeed_wdt_is_enabled(s)) {
186             s->regs[WDT_CTRL] = data;
187             awc->wdt_reload(s);
188         } else if (!enable && aspeed_wdt_is_enabled(s)) {
189             s->regs[WDT_CTRL] = data;
190             timer_del(s->timer);
191         } else {
192             s->regs[WDT_CTRL] = data;
193         }
194         break;
195     case WDT_RESET_WIDTH:
196         if (awc->reset_pulse) {
197             awc->reset_pulse(s, data & WDT_POLARITY_MASK);
198         }
199         s->regs[WDT_RESET_WIDTH] &= ~awc->ext_pulse_width_mask;
200         s->regs[WDT_RESET_WIDTH] |= data & awc->ext_pulse_width_mask;
201         break;
202 
203     case WDT_RESET_MASK1:
204         /* TODO: implement */
205         s->regs[WDT_RESET_MASK1] = data;
206         break;
207 
208     case WDT_TIMEOUT_STATUS:
209     case WDT_TIMEOUT_CLEAR:
210     case WDT_RESET_MASK2:
211     case WDT_SW_RESET_MASK1:
212     case WDT_SW_RESET_MASK2:
213         qemu_log_mask(LOG_UNIMP,
214                       "%s: uninmplemented write at offset 0x%" HWADDR_PRIx "\n",
215                       __func__, offset);
216         break;
217     case WDT_SW_RESET_CTRL:
218         if (aspeed_wdt_is_soc_reset_mode(s) &&
219             (data == WDT_SW_RESET_ENABLE)) {
220             watchdog_perform_action();
221         }
222         break;
223     default:
224         qemu_log_mask(LOG_GUEST_ERROR,
225                       "%s: Out-of-bounds write at offset 0x%" HWADDR_PRIx "\n",
226                       __func__, offset);
227     }
228     return;
229 }
230 
231 static const VMStateDescription vmstate_aspeed_wdt = {
232     .name = "vmstate_aspeed_wdt",
233     .version_id = 0,
234     .minimum_version_id = 0,
235     .fields = (const VMStateField[]) {
236         VMSTATE_TIMER_PTR(timer, AspeedWDTState),
237         VMSTATE_UINT32_ARRAY(regs, AspeedWDTState, ASPEED_WDT_REGS_MAX),
238         VMSTATE_END_OF_LIST()
239     }
240 };
241 
242 static const MemoryRegionOps aspeed_wdt_ops = {
243     .read = aspeed_wdt_read,
244     .write = aspeed_wdt_write,
245     .endianness = DEVICE_LITTLE_ENDIAN,
246     .valid.min_access_size = 4,
247     .valid.max_access_size = 4,
248     .valid.unaligned = false,
249 };
250 
251 static void aspeed_wdt_reset(DeviceState *dev)
252 {
253     AspeedWDTState *s = ASPEED_WDT(dev);
254     AspeedWDTClass *awc = ASPEED_WDT_GET_CLASS(s);
255 
256     s->regs[WDT_STATUS] = awc->default_status;
257     s->regs[WDT_RELOAD_VALUE] = awc->default_reload_value;
258     s->regs[WDT_RESTART] = 0;
259     s->regs[WDT_CTRL] = awc->sanitize_ctrl(0);
260     s->regs[WDT_RESET_WIDTH] = 0xFF;
261 
262     timer_del(s->timer);
263 }
264 
265 static void aspeed_wdt_timer_expired(void *dev)
266 {
267     AspeedWDTState *s = ASPEED_WDT(dev);
268     uint32_t reset_ctrl_reg = ASPEED_WDT_GET_CLASS(s)->reset_ctrl_reg;
269 
270     /* Do not reset on SDRAM controller reset */
271     if (s->scu->regs[reset_ctrl_reg] & SCU_RESET_SDRAM) {
272         timer_del(s->timer);
273         s->regs[WDT_CTRL] = 0;
274         return;
275     }
276 
277     qemu_log_mask(CPU_LOG_RESET, "Watchdog timer %" HWADDR_PRIx " expired.\n",
278                   s->iomem.addr);
279     watchdog_perform_action();
280     timer_del(s->timer);
281 }
282 
283 #define PCLK_HZ 24000000
284 
285 static void aspeed_wdt_realize(DeviceState *dev, Error **errp)
286 {
287     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
288     AspeedWDTState *s = ASPEED_WDT(dev);
289     AspeedWDTClass *awc = ASPEED_WDT_GET_CLASS(dev);
290 
291     assert(s->scu);
292 
293     s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, aspeed_wdt_timer_expired, dev);
294 
295     /*
296      * FIXME: This setting should be derived from the SCU hw strapping
297      * register SCU70
298      */
299     s->pclk_freq = PCLK_HZ;
300 
301     memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_wdt_ops, s,
302                           TYPE_ASPEED_WDT, awc->iosize);
303     sysbus_init_mmio(sbd, &s->iomem);
304 }
305 
306 static const Property aspeed_wdt_properties[] = {
307     DEFINE_PROP_LINK("scu", AspeedWDTState, scu, TYPE_ASPEED_SCU,
308                      AspeedSCUState *),
309 };
310 
311 static void aspeed_wdt_class_init(ObjectClass *klass, void *data)
312 {
313     DeviceClass *dc = DEVICE_CLASS(klass);
314 
315     dc->desc = "ASPEED Watchdog Controller";
316     dc->realize = aspeed_wdt_realize;
317     device_class_set_legacy_reset(dc, aspeed_wdt_reset);
318     set_bit(DEVICE_CATEGORY_WATCHDOG, dc->categories);
319     dc->vmsd = &vmstate_aspeed_wdt;
320     device_class_set_props(dc, aspeed_wdt_properties);
321     dc->desc = "Aspeed watchdog device";
322 }
323 
324 static const TypeInfo aspeed_wdt_info = {
325     .parent = TYPE_SYS_BUS_DEVICE,
326     .name  = TYPE_ASPEED_WDT,
327     .instance_size  = sizeof(AspeedWDTState),
328     .class_init = aspeed_wdt_class_init,
329     .class_size    = sizeof(AspeedWDTClass),
330     .abstract      = true,
331 };
332 
333 static void aspeed_2400_wdt_class_init(ObjectClass *klass, void *data)
334 {
335     DeviceClass *dc = DEVICE_CLASS(klass);
336     AspeedWDTClass *awc = ASPEED_WDT_CLASS(klass);
337 
338     dc->desc = "ASPEED 2400 Watchdog Controller";
339     awc->iosize = 0x20;
340     awc->ext_pulse_width_mask = 0xff;
341     awc->reset_ctrl_reg = SCU_RESET_CONTROL1;
342     awc->wdt_reload = aspeed_wdt_reload;
343     awc->sanitize_ctrl = aspeed_2400_sanitize_ctrl;
344     awc->default_status = 0x03EF1480;
345     awc->default_reload_value = 0x03EF1480;
346 }
347 
348 static const TypeInfo aspeed_2400_wdt_info = {
349     .name = TYPE_ASPEED_2400_WDT,
350     .parent = TYPE_ASPEED_WDT,
351     .instance_size = sizeof(AspeedWDTState),
352     .class_init = aspeed_2400_wdt_class_init,
353 };
354 
355 static void aspeed_2500_wdt_reset_pulse(AspeedWDTState *s, uint32_t property)
356 {
357     if (property) {
358         if (property == WDT_ACTIVE_HIGH_MAGIC) {
359             s->regs[WDT_RESET_WIDTH] |= WDT_RESET_WIDTH_ACTIVE_HIGH;
360         } else if (property == WDT_ACTIVE_LOW_MAGIC) {
361             s->regs[WDT_RESET_WIDTH] &= ~WDT_RESET_WIDTH_ACTIVE_HIGH;
362         } else if (property == WDT_PUSH_PULL_MAGIC) {
363             s->regs[WDT_RESET_WIDTH] |= WDT_RESET_WIDTH_PUSH_PULL;
364         } else if (property == WDT_OPEN_DRAIN_MAGIC) {
365             s->regs[WDT_RESET_WIDTH] &= ~WDT_RESET_WIDTH_PUSH_PULL;
366         }
367     }
368 }
369 
370 static void aspeed_2500_wdt_class_init(ObjectClass *klass, void *data)
371 {
372     DeviceClass *dc = DEVICE_CLASS(klass);
373     AspeedWDTClass *awc = ASPEED_WDT_CLASS(klass);
374 
375     dc->desc = "ASPEED 2500 Watchdog Controller";
376     awc->iosize = 0x20;
377     awc->ext_pulse_width_mask = 0xfffff;
378     awc->reset_ctrl_reg = SCU_RESET_CONTROL1;
379     awc->reset_pulse = aspeed_2500_wdt_reset_pulse;
380     awc->wdt_reload = aspeed_wdt_reload_1mhz;
381     awc->sanitize_ctrl = aspeed_2500_sanitize_ctrl;
382     awc->default_status = 0x014FB180;
383     awc->default_reload_value = 0x014FB180;
384 }
385 
386 static const TypeInfo aspeed_2500_wdt_info = {
387     .name = TYPE_ASPEED_2500_WDT,
388     .parent = TYPE_ASPEED_WDT,
389     .instance_size = sizeof(AspeedWDTState),
390     .class_init = aspeed_2500_wdt_class_init,
391 };
392 
393 static void aspeed_2600_wdt_class_init(ObjectClass *klass, void *data)
394 {
395     DeviceClass *dc = DEVICE_CLASS(klass);
396     AspeedWDTClass *awc = ASPEED_WDT_CLASS(klass);
397 
398     dc->desc = "ASPEED 2600 Watchdog Controller";
399     awc->iosize = 0x40;
400     awc->ext_pulse_width_mask = 0xfffff; /* TODO */
401     awc->reset_ctrl_reg = AST2600_SCU_RESET_CONTROL1;
402     awc->reset_pulse = aspeed_2500_wdt_reset_pulse;
403     awc->wdt_reload = aspeed_wdt_reload_1mhz;
404     awc->sanitize_ctrl = aspeed_2600_sanitize_ctrl;
405     awc->default_status = 0x014FB180;
406     awc->default_reload_value = 0x014FB180;
407 }
408 
409 static const TypeInfo aspeed_2600_wdt_info = {
410     .name = TYPE_ASPEED_2600_WDT,
411     .parent = TYPE_ASPEED_WDT,
412     .instance_size = sizeof(AspeedWDTState),
413     .class_init = aspeed_2600_wdt_class_init,
414 };
415 
416 static void aspeed_1030_wdt_class_init(ObjectClass *klass, void *data)
417 {
418     DeviceClass *dc = DEVICE_CLASS(klass);
419     AspeedWDTClass *awc = ASPEED_WDT_CLASS(klass);
420 
421     dc->desc = "ASPEED 1030 Watchdog Controller";
422     awc->iosize = 0x80;
423     awc->ext_pulse_width_mask = 0xfffff; /* TODO */
424     awc->reset_ctrl_reg = AST2600_SCU_RESET_CONTROL1;
425     awc->reset_pulse = aspeed_2500_wdt_reset_pulse;
426     awc->wdt_reload = aspeed_wdt_reload_1mhz;
427     awc->sanitize_ctrl = aspeed_2600_sanitize_ctrl;
428     awc->default_status = 0x014FB180;
429     awc->default_reload_value = 0x014FB180;
430 }
431 
432 static const TypeInfo aspeed_1030_wdt_info = {
433     .name = TYPE_ASPEED_1030_WDT,
434     .parent = TYPE_ASPEED_WDT,
435     .instance_size = sizeof(AspeedWDTState),
436     .class_init = aspeed_1030_wdt_class_init,
437 };
438 
439 static void aspeed_2700_wdt_class_init(ObjectClass *klass, void *data)
440 {
441     DeviceClass *dc = DEVICE_CLASS(klass);
442     AspeedWDTClass *awc = ASPEED_WDT_CLASS(klass);
443 
444     dc->desc = "ASPEED 2700 Watchdog Controller";
445     awc->iosize = 0x80;
446     awc->ext_pulse_width_mask = 0xfffff; /* TODO */
447     awc->reset_ctrl_reg = AST2600_SCU_RESET_CONTROL1;
448     awc->reset_pulse = aspeed_2500_wdt_reset_pulse;
449     awc->wdt_reload = aspeed_wdt_reload_1mhz;
450     awc->sanitize_ctrl = aspeed_2600_sanitize_ctrl;
451     awc->default_status = 0x014FB180;
452     awc->default_reload_value = 0x014FB180;
453 }
454 
455 static const TypeInfo aspeed_2700_wdt_info = {
456     .name = TYPE_ASPEED_2700_WDT,
457     .parent = TYPE_ASPEED_WDT,
458     .instance_size = sizeof(AspeedWDTState),
459     .class_init = aspeed_2700_wdt_class_init,
460 };
461 
462 static void wdt_aspeed_register_types(void)
463 {
464     type_register_static(&aspeed_wdt_info);
465     type_register_static(&aspeed_2400_wdt_info);
466     type_register_static(&aspeed_2500_wdt_info);
467     type_register_static(&aspeed_2600_wdt_info);
468     type_register_static(&aspeed_2700_wdt_info);
469     type_register_static(&aspeed_1030_wdt_info);
470 }
471 
472 type_init(wdt_aspeed_register_types)
473