xref: /openbmc/qemu/hw/watchdog/wdt_aspeed.c (revision d0bf492f)
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 "sysemu/watchdog.h"
17 #include "hw/misc/aspeed_scu.h"
18 #include "hw/qdev-properties.h"
19 #include "hw/sysbus.h"
20 #include "hw/watchdog/wdt_aspeed.h"
21 #include "migration/vmstate.h"
22 #include "trace.h"
23 
24 #define WDT_STATUS                      (0x00 / 4)
25 #define WDT_RELOAD_VALUE                (0x04 / 4)
26 #define WDT_RESTART                     (0x08 / 4)
27 #define WDT_CTRL                        (0x0C / 4)
28 #define   WDT_CTRL_RESET_MODE_SOC       (0x00 << 5)
29 #define   WDT_CTRL_RESET_MODE_FULL_CHIP (0x01 << 5)
30 #define   WDT_CTRL_1MHZ_CLK             BIT(4)
31 #define   WDT_CTRL_WDT_EXT              BIT(3)
32 #define   WDT_CTRL_WDT_INTR             BIT(2)
33 #define   WDT_CTRL_RESET_SYSTEM         BIT(1)
34 #define   WDT_CTRL_ENABLE               BIT(0)
35 #define WDT_RESET_WIDTH                 (0x18 / 4)
36 #define   WDT_RESET_WIDTH_ACTIVE_HIGH   BIT(31)
37 #define     WDT_POLARITY_MASK           (0xFF << 24)
38 #define     WDT_ACTIVE_HIGH_MAGIC       (0xA5 << 24)
39 #define     WDT_ACTIVE_LOW_MAGIC        (0x5A << 24)
40 #define   WDT_RESET_WIDTH_PUSH_PULL     BIT(30)
41 #define     WDT_DRIVE_TYPE_MASK         (0xFF << 24)
42 #define     WDT_PUSH_PULL_MAGIC         (0xA8 << 24)
43 #define     WDT_OPEN_DRAIN_MAGIC        (0x8A << 24)
44 #define WDT_RESET_MASK1                 (0x1c / 4)
45 #define WDT_RESET_MASK2                 (0x20 / 4)
46 
47 #define WDT_SW_RESET_CTRL               (0x24 / 4)
48 #define WDT_SW_RESET_MASK1              (0x28 / 4)
49 #define WDT_SW_RESET_MASK2              (0x2c / 4)
50 
51 #define WDT_TIMEOUT_STATUS              (0x10 / 4)
52 #define WDT_TIMEOUT_CLEAR               (0x14 / 4)
53 
54 #define WDT_RESTART_MAGIC               0x4755
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_enabled(const AspeedWDTState *s)
61 {
62     return s->regs[WDT_CTRL] & WDT_CTRL_ENABLE;
63 }
64 
65 static uint64_t aspeed_wdt_read(void *opaque, hwaddr offset, unsigned size)
66 {
67     AspeedWDTState *s = ASPEED_WDT(opaque);
68 
69     trace_aspeed_wdt_read(offset, size);
70 
71     offset >>= 2;
72 
73     switch (offset) {
74     case WDT_STATUS:
75         return s->regs[WDT_STATUS];
76     case WDT_RELOAD_VALUE:
77         return s->regs[WDT_RELOAD_VALUE];
78     case WDT_RESTART:
79         qemu_log_mask(LOG_GUEST_ERROR,
80                       "%s: read from write-only reg at offset 0x%"
81                       HWADDR_PRIx "\n", __func__, offset);
82         return 0;
83     case WDT_CTRL:
84         return s->regs[WDT_CTRL];
85     case WDT_RESET_WIDTH:
86         return s->regs[WDT_RESET_WIDTH];
87     case WDT_RESET_MASK1:
88         return s->regs[WDT_RESET_MASK1];
89     case WDT_TIMEOUT_STATUS:
90     case WDT_TIMEOUT_CLEAR:
91     case WDT_RESET_MASK2:
92     case WDT_SW_RESET_CTRL:
93     case WDT_SW_RESET_MASK1:
94     case WDT_SW_RESET_MASK2:
95         qemu_log_mask(LOG_UNIMP,
96                       "%s: uninmplemented read at offset 0x%" HWADDR_PRIx "\n",
97                       __func__, offset);
98         return 0;
99     default:
100         qemu_log_mask(LOG_GUEST_ERROR,
101                       "%s: Out-of-bounds read at offset 0x%" HWADDR_PRIx "\n",
102                       __func__, offset);
103         return 0;
104     }
105 
106 }
107 
108 static void aspeed_wdt_reload(AspeedWDTState *s)
109 {
110     uint64_t reload;
111 
112     if (!(s->regs[WDT_CTRL] & WDT_CTRL_1MHZ_CLK)) {
113         reload = muldiv64(s->regs[WDT_RELOAD_VALUE], NANOSECONDS_PER_SECOND,
114                           s->pclk_freq);
115     } else {
116         reload = s->regs[WDT_RELOAD_VALUE] * 1000ULL;
117     }
118 
119     if (aspeed_wdt_is_enabled(s)) {
120         timer_mod(s->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + reload);
121     }
122 }
123 
124 static void aspeed_wdt_reload_1mhz(AspeedWDTState *s)
125 {
126     uint64_t reload = s->regs[WDT_RELOAD_VALUE] * 1000ULL;
127 
128     if (aspeed_wdt_is_enabled(s)) {
129         timer_mod(s->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + reload);
130     }
131 }
132 
133 static uint64_t aspeed_2400_sanitize_ctrl(uint64_t data)
134 {
135     return data & 0xffff;
136 }
137 
138 static uint64_t aspeed_2500_sanitize_ctrl(uint64_t data)
139 {
140     return (data & ~(0xfUL << 8)) | WDT_CTRL_1MHZ_CLK;
141 }
142 
143 static uint64_t aspeed_2600_sanitize_ctrl(uint64_t data)
144 {
145     return data & ~(0x7UL << 7);
146 }
147 
148 static void aspeed_wdt_write(void *opaque, hwaddr offset, uint64_t data,
149                              unsigned size)
150 {
151     AspeedWDTState *s = ASPEED_WDT(opaque);
152     AspeedWDTClass *awc = ASPEED_WDT_GET_CLASS(s);
153     bool enable;
154 
155     trace_aspeed_wdt_write(offset, size, data);
156 
157     offset >>= 2;
158 
159     switch (offset) {
160     case WDT_STATUS:
161         qemu_log_mask(LOG_GUEST_ERROR,
162                       "%s: write to read-only reg at offset 0x%"
163                       HWADDR_PRIx "\n", __func__, offset);
164         break;
165     case WDT_RELOAD_VALUE:
166         s->regs[WDT_RELOAD_VALUE] = data;
167         break;
168     case WDT_RESTART:
169         if ((data & 0xFFFF) == WDT_RESTART_MAGIC) {
170             s->regs[WDT_STATUS] = s->regs[WDT_RELOAD_VALUE];
171             awc->wdt_reload(s);
172         }
173         break;
174     case WDT_CTRL:
175         data = awc->sanitize_ctrl(data);
176         enable = data & WDT_CTRL_ENABLE;
177         if (enable && !aspeed_wdt_is_enabled(s)) {
178             s->regs[WDT_CTRL] = data;
179             awc->wdt_reload(s);
180         } else if (!enable && aspeed_wdt_is_enabled(s)) {
181             s->regs[WDT_CTRL] = data;
182             timer_del(s->timer);
183         } else {
184             s->regs[WDT_CTRL] = data;
185         }
186         break;
187     case WDT_RESET_WIDTH:
188         if (awc->reset_pulse) {
189             awc->reset_pulse(s, data & WDT_POLARITY_MASK);
190         }
191         s->regs[WDT_RESET_WIDTH] &= ~awc->ext_pulse_width_mask;
192         s->regs[WDT_RESET_WIDTH] |= data & awc->ext_pulse_width_mask;
193         break;
194 
195     case WDT_RESET_MASK1:
196         /* TODO: implement */
197         s->regs[WDT_RESET_MASK1] = data;
198         break;
199 
200     case WDT_TIMEOUT_STATUS:
201     case WDT_TIMEOUT_CLEAR:
202     case WDT_RESET_MASK2:
203     case WDT_SW_RESET_CTRL:
204     case WDT_SW_RESET_MASK1:
205     case WDT_SW_RESET_MASK2:
206         qemu_log_mask(LOG_UNIMP,
207                       "%s: uninmplemented write at offset 0x%" HWADDR_PRIx "\n",
208                       __func__, offset);
209         break;
210     default:
211         qemu_log_mask(LOG_GUEST_ERROR,
212                       "%s: Out-of-bounds write at offset 0x%" HWADDR_PRIx "\n",
213                       __func__, offset);
214     }
215     return;
216 }
217 
218 static const VMStateDescription vmstate_aspeed_wdt = {
219     .name = "vmstate_aspeed_wdt",
220     .version_id = 0,
221     .minimum_version_id = 0,
222     .fields = (VMStateField[]) {
223         VMSTATE_TIMER_PTR(timer, AspeedWDTState),
224         VMSTATE_UINT32_ARRAY(regs, AspeedWDTState, ASPEED_WDT_REGS_MAX),
225         VMSTATE_END_OF_LIST()
226     }
227 };
228 
229 static const MemoryRegionOps aspeed_wdt_ops = {
230     .read = aspeed_wdt_read,
231     .write = aspeed_wdt_write,
232     .endianness = DEVICE_LITTLE_ENDIAN,
233     .valid.min_access_size = 4,
234     .valid.max_access_size = 4,
235     .valid.unaligned = false,
236 };
237 
238 static void aspeed_wdt_reset(DeviceState *dev)
239 {
240     AspeedWDTState *s = ASPEED_WDT(dev);
241     AspeedWDTClass *awc = ASPEED_WDT_GET_CLASS(s);
242 
243     s->regs[WDT_STATUS] = awc->default_status;
244     s->regs[WDT_RELOAD_VALUE] = awc->default_reload_value;
245     s->regs[WDT_RESTART] = 0;
246     s->regs[WDT_CTRL] = awc->sanitize_ctrl(0);
247     s->regs[WDT_RESET_WIDTH] = 0xFF;
248 
249     timer_del(s->timer);
250 }
251 
252 static void aspeed_wdt_timer_expired(void *dev)
253 {
254     AspeedWDTState *s = ASPEED_WDT(dev);
255     uint32_t reset_ctrl_reg = ASPEED_WDT_GET_CLASS(s)->reset_ctrl_reg;
256 
257     /* Do not reset on SDRAM controller reset */
258     if (s->scu->regs[reset_ctrl_reg] & SCU_RESET_SDRAM) {
259         timer_del(s->timer);
260         s->regs[WDT_CTRL] = 0;
261         return;
262     }
263 
264     qemu_log_mask(CPU_LOG_RESET, "Watchdog timer %" HWADDR_PRIx " expired.\n",
265                   s->iomem.addr);
266     watchdog_perform_action();
267     timer_del(s->timer);
268 }
269 
270 #define PCLK_HZ 24000000
271 
272 static void aspeed_wdt_realize(DeviceState *dev, Error **errp)
273 {
274     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
275     AspeedWDTState *s = ASPEED_WDT(dev);
276     AspeedWDTClass *awc = ASPEED_WDT_GET_CLASS(dev);
277 
278     assert(s->scu);
279 
280     s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, aspeed_wdt_timer_expired, dev);
281 
282     /* FIXME: This setting should be derived from the SCU hw strapping
283      * register SCU70
284      */
285     s->pclk_freq = PCLK_HZ;
286 
287     memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_wdt_ops, s,
288                           TYPE_ASPEED_WDT, awc->iosize);
289     sysbus_init_mmio(sbd, &s->iomem);
290 }
291 
292 static Property aspeed_wdt_properties[] = {
293     DEFINE_PROP_LINK("scu", AspeedWDTState, scu, TYPE_ASPEED_SCU,
294                      AspeedSCUState *),
295     DEFINE_PROP_END_OF_LIST(),
296 };
297 
298 static void aspeed_wdt_class_init(ObjectClass *klass, void *data)
299 {
300     DeviceClass *dc = DEVICE_CLASS(klass);
301 
302     dc->desc = "ASPEED Watchdog Controller";
303     dc->realize = aspeed_wdt_realize;
304     dc->reset = aspeed_wdt_reset;
305     set_bit(DEVICE_CATEGORY_WATCHDOG, dc->categories);
306     dc->vmsd = &vmstate_aspeed_wdt;
307     device_class_set_props(dc, aspeed_wdt_properties);
308     dc->desc = "Aspeed watchdog device";
309 }
310 
311 static const TypeInfo aspeed_wdt_info = {
312     .parent = TYPE_SYS_BUS_DEVICE,
313     .name  = TYPE_ASPEED_WDT,
314     .instance_size  = sizeof(AspeedWDTState),
315     .class_init = aspeed_wdt_class_init,
316     .class_size    = sizeof(AspeedWDTClass),
317     .abstract      = true,
318 };
319 
320 static void aspeed_2400_wdt_class_init(ObjectClass *klass, void *data)
321 {
322     DeviceClass *dc = DEVICE_CLASS(klass);
323     AspeedWDTClass *awc = ASPEED_WDT_CLASS(klass);
324 
325     dc->desc = "ASPEED 2400 Watchdog Controller";
326     awc->iosize = 0x20;
327     awc->ext_pulse_width_mask = 0xff;
328     awc->reset_ctrl_reg = SCU_RESET_CONTROL1;
329     awc->wdt_reload = aspeed_wdt_reload;
330     awc->sanitize_ctrl = aspeed_2400_sanitize_ctrl;
331     awc->default_status = 0x03EF1480;
332     awc->default_reload_value = 0x03EF1480;
333 }
334 
335 static const TypeInfo aspeed_2400_wdt_info = {
336     .name = TYPE_ASPEED_2400_WDT,
337     .parent = TYPE_ASPEED_WDT,
338     .instance_size = sizeof(AspeedWDTState),
339     .class_init = aspeed_2400_wdt_class_init,
340 };
341 
342 static void aspeed_2500_wdt_reset_pulse(AspeedWDTState *s, uint32_t property)
343 {
344     if (property) {
345         if (property == WDT_ACTIVE_HIGH_MAGIC) {
346             s->regs[WDT_RESET_WIDTH] |= WDT_RESET_WIDTH_ACTIVE_HIGH;
347         } else if (property == WDT_ACTIVE_LOW_MAGIC) {
348             s->regs[WDT_RESET_WIDTH] &= ~WDT_RESET_WIDTH_ACTIVE_HIGH;
349         } else if (property == WDT_PUSH_PULL_MAGIC) {
350             s->regs[WDT_RESET_WIDTH] |= WDT_RESET_WIDTH_PUSH_PULL;
351         } else if (property == WDT_OPEN_DRAIN_MAGIC) {
352             s->regs[WDT_RESET_WIDTH] &= ~WDT_RESET_WIDTH_PUSH_PULL;
353         }
354     }
355 }
356 
357 static void aspeed_2500_wdt_class_init(ObjectClass *klass, void *data)
358 {
359     DeviceClass *dc = DEVICE_CLASS(klass);
360     AspeedWDTClass *awc = ASPEED_WDT_CLASS(klass);
361 
362     dc->desc = "ASPEED 2500 Watchdog Controller";
363     awc->iosize = 0x20;
364     awc->ext_pulse_width_mask = 0xfffff;
365     awc->reset_ctrl_reg = SCU_RESET_CONTROL1;
366     awc->reset_pulse = aspeed_2500_wdt_reset_pulse;
367     awc->wdt_reload = aspeed_wdt_reload_1mhz;
368     awc->sanitize_ctrl = aspeed_2500_sanitize_ctrl;
369     awc->default_status = 0x014FB180;
370     awc->default_reload_value = 0x014FB180;
371 }
372 
373 static const TypeInfo aspeed_2500_wdt_info = {
374     .name = TYPE_ASPEED_2500_WDT,
375     .parent = TYPE_ASPEED_WDT,
376     .instance_size = sizeof(AspeedWDTState),
377     .class_init = aspeed_2500_wdt_class_init,
378 };
379 
380 static void aspeed_2600_wdt_class_init(ObjectClass *klass, void *data)
381 {
382     DeviceClass *dc = DEVICE_CLASS(klass);
383     AspeedWDTClass *awc = ASPEED_WDT_CLASS(klass);
384 
385     dc->desc = "ASPEED 2600 Watchdog Controller";
386     awc->iosize = 0x40;
387     awc->ext_pulse_width_mask = 0xfffff; /* TODO */
388     awc->reset_ctrl_reg = AST2600_SCU_RESET_CONTROL1;
389     awc->reset_pulse = aspeed_2500_wdt_reset_pulse;
390     awc->wdt_reload = aspeed_wdt_reload_1mhz;
391     awc->sanitize_ctrl = aspeed_2600_sanitize_ctrl;
392     awc->default_status = 0x014FB180;
393     awc->default_reload_value = 0x014FB180;
394 }
395 
396 static const TypeInfo aspeed_2600_wdt_info = {
397     .name = TYPE_ASPEED_2600_WDT,
398     .parent = TYPE_ASPEED_WDT,
399     .instance_size = sizeof(AspeedWDTState),
400     .class_init = aspeed_2600_wdt_class_init,
401 };
402 
403 static void aspeed_1030_wdt_class_init(ObjectClass *klass, void *data)
404 {
405     DeviceClass *dc = DEVICE_CLASS(klass);
406     AspeedWDTClass *awc = ASPEED_WDT_CLASS(klass);
407 
408     dc->desc = "ASPEED 1030 Watchdog Controller";
409     awc->iosize = 0x80;
410     awc->ext_pulse_width_mask = 0xfffff; /* TODO */
411     awc->reset_ctrl_reg = AST2600_SCU_RESET_CONTROL1;
412     awc->reset_pulse = aspeed_2500_wdt_reset_pulse;
413     awc->wdt_reload = aspeed_wdt_reload_1mhz;
414     awc->sanitize_ctrl = aspeed_2600_sanitize_ctrl;
415     awc->default_status = 0x014FB180;
416     awc->default_reload_value = 0x014FB180;
417 }
418 
419 static const TypeInfo aspeed_1030_wdt_info = {
420     .name = TYPE_ASPEED_1030_WDT,
421     .parent = TYPE_ASPEED_WDT,
422     .instance_size = sizeof(AspeedWDTState),
423     .class_init = aspeed_1030_wdt_class_init,
424 };
425 
426 static void wdt_aspeed_register_types(void)
427 {
428     type_register_static(&aspeed_wdt_info);
429     type_register_static(&aspeed_2400_wdt_info);
430     type_register_static(&aspeed_2500_wdt_info);
431     type_register_static(&aspeed_2600_wdt_info);
432     type_register_static(&aspeed_1030_wdt_info);
433 }
434 
435 type_init(wdt_aspeed_register_types)
436