xref: /openbmc/qemu/hw/watchdog/wdt_aspeed.c (revision ffe98631)
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 
46 #define WDT_TIMEOUT_STATUS              (0x10 / 4)
47 #define WDT_TIMEOUT_CLEAR               (0x14 / 4)
48 
49 #define WDT_RESTART_MAGIC               0x4755
50 
51 #define AST2600_SCU_RESET_CONTROL1      (0x40 / 4)
52 #define SCU_RESET_CONTROL1              (0x04 / 4)
53 #define    SCU_RESET_SDRAM              BIT(0)
54 
55 static bool aspeed_wdt_is_enabled(const AspeedWDTState *s)
56 {
57     return s->regs[WDT_CTRL] & WDT_CTRL_ENABLE;
58 }
59 
60 static uint64_t aspeed_wdt_read(void *opaque, hwaddr offset, unsigned size)
61 {
62     AspeedWDTState *s = ASPEED_WDT(opaque);
63 
64     trace_aspeed_wdt_read(offset, size);
65 
66     offset >>= 2;
67 
68     switch (offset) {
69     case WDT_STATUS:
70         return s->regs[WDT_STATUS];
71     case WDT_RELOAD_VALUE:
72         return s->regs[WDT_RELOAD_VALUE];
73     case WDT_RESTART:
74         qemu_log_mask(LOG_GUEST_ERROR,
75                       "%s: read from write-only reg at offset 0x%"
76                       HWADDR_PRIx "\n", __func__, offset);
77         return 0;
78     case WDT_CTRL:
79         return s->regs[WDT_CTRL];
80     case WDT_RESET_WIDTH:
81         return s->regs[WDT_RESET_WIDTH];
82     case WDT_RESET_MASK1:
83         return s->regs[WDT_RESET_MASK1];
84     case WDT_TIMEOUT_STATUS:
85     case WDT_TIMEOUT_CLEAR:
86         qemu_log_mask(LOG_UNIMP,
87                       "%s: uninmplemented read at offset 0x%" HWADDR_PRIx "\n",
88                       __func__, offset);
89         return 0;
90     default:
91         qemu_log_mask(LOG_GUEST_ERROR,
92                       "%s: Out-of-bounds read at offset 0x%" HWADDR_PRIx "\n",
93                       __func__, offset);
94         return 0;
95     }
96 
97 }
98 
99 static void aspeed_wdt_reload(AspeedWDTState *s)
100 {
101     uint64_t reload;
102 
103     if (!(s->regs[WDT_CTRL] & WDT_CTRL_1MHZ_CLK)) {
104         reload = muldiv64(s->regs[WDT_RELOAD_VALUE], NANOSECONDS_PER_SECOND,
105                           s->pclk_freq);
106     } else {
107         reload = s->regs[WDT_RELOAD_VALUE] * 1000ULL;
108     }
109 
110     if (aspeed_wdt_is_enabled(s)) {
111         timer_mod(s->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + reload);
112     }
113 }
114 
115 static void aspeed_wdt_reload_1mhz(AspeedWDTState *s)
116 {
117     uint64_t reload = s->regs[WDT_RELOAD_VALUE] * 1000ULL;
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 uint64_t aspeed_2400_sanitize_ctrl(uint64_t data)
125 {
126     return data & 0xffff;
127 }
128 
129 static uint64_t aspeed_2500_sanitize_ctrl(uint64_t data)
130 {
131     return (data & ~(0xfUL << 8)) | WDT_CTRL_1MHZ_CLK;
132 }
133 
134 static uint64_t aspeed_2600_sanitize_ctrl(uint64_t data)
135 {
136     return data & ~(0x7UL << 7);
137 }
138 
139 static void aspeed_wdt_write(void *opaque, hwaddr offset, uint64_t data,
140                              unsigned size)
141 {
142     AspeedWDTState *s = ASPEED_WDT(opaque);
143     AspeedWDTClass *awc = ASPEED_WDT_GET_CLASS(s);
144     bool enable;
145 
146     trace_aspeed_wdt_write(offset, size, data);
147 
148     offset >>= 2;
149 
150     switch (offset) {
151     case WDT_STATUS:
152         qemu_log_mask(LOG_GUEST_ERROR,
153                       "%s: write to read-only reg at offset 0x%"
154                       HWADDR_PRIx "\n", __func__, offset);
155         break;
156     case WDT_RELOAD_VALUE:
157         s->regs[WDT_RELOAD_VALUE] = data;
158         break;
159     case WDT_RESTART:
160         if ((data & 0xFFFF) == WDT_RESTART_MAGIC) {
161             s->regs[WDT_STATUS] = s->regs[WDT_RELOAD_VALUE];
162             awc->wdt_reload(s);
163         }
164         break;
165     case WDT_CTRL:
166         data = awc->sanitize_ctrl(data);
167         enable = data & WDT_CTRL_ENABLE;
168         if (enable && !aspeed_wdt_is_enabled(s)) {
169             s->regs[WDT_CTRL] = data;
170             awc->wdt_reload(s);
171         } else if (!enable && aspeed_wdt_is_enabled(s)) {
172             s->regs[WDT_CTRL] = data;
173             timer_del(s->timer);
174         } else {
175             s->regs[WDT_CTRL] = data;
176         }
177         break;
178     case WDT_RESET_WIDTH:
179         if (awc->reset_pulse) {
180             awc->reset_pulse(s, data & WDT_POLARITY_MASK);
181         }
182         s->regs[WDT_RESET_WIDTH] &= ~awc->ext_pulse_width_mask;
183         s->regs[WDT_RESET_WIDTH] |= data & awc->ext_pulse_width_mask;
184         break;
185 
186     case WDT_RESET_MASK1:
187         /* TODO: implement */
188         s->regs[WDT_RESET_MASK1] = data;
189         break;
190 
191     case WDT_TIMEOUT_STATUS:
192     case WDT_TIMEOUT_CLEAR:
193         qemu_log_mask(LOG_UNIMP,
194                       "%s: uninmplemented write at offset 0x%" HWADDR_PRIx "\n",
195                       __func__, offset);
196         break;
197     default:
198         qemu_log_mask(LOG_GUEST_ERROR,
199                       "%s: Out-of-bounds write at offset 0x%" HWADDR_PRIx "\n",
200                       __func__, offset);
201     }
202     return;
203 }
204 
205 static const VMStateDescription vmstate_aspeed_wdt = {
206     .name = "vmstate_aspeed_wdt",
207     .version_id = 0,
208     .minimum_version_id = 0,
209     .fields = (VMStateField[]) {
210         VMSTATE_TIMER_PTR(timer, AspeedWDTState),
211         VMSTATE_UINT32_ARRAY(regs, AspeedWDTState, ASPEED_WDT_REGS_MAX),
212         VMSTATE_END_OF_LIST()
213     }
214 };
215 
216 static const MemoryRegionOps aspeed_wdt_ops = {
217     .read = aspeed_wdt_read,
218     .write = aspeed_wdt_write,
219     .endianness = DEVICE_LITTLE_ENDIAN,
220     .valid.min_access_size = 4,
221     .valid.max_access_size = 4,
222     .valid.unaligned = false,
223 };
224 
225 static void aspeed_wdt_reset(DeviceState *dev)
226 {
227     AspeedWDTState *s = ASPEED_WDT(dev);
228     AspeedWDTClass *awc = ASPEED_WDT_GET_CLASS(s);
229 
230     s->regs[WDT_STATUS] = awc->default_status;
231     s->regs[WDT_RELOAD_VALUE] = awc->default_reload_value;
232     s->regs[WDT_RESTART] = 0;
233     s->regs[WDT_CTRL] = awc->sanitize_ctrl(0);
234     s->regs[WDT_RESET_WIDTH] = 0xFF;
235 
236     timer_del(s->timer);
237 }
238 
239 static void aspeed_wdt_timer_expired(void *dev)
240 {
241     AspeedWDTState *s = ASPEED_WDT(dev);
242     uint32_t reset_ctrl_reg = ASPEED_WDT_GET_CLASS(s)->reset_ctrl_reg;
243 
244     /* Do not reset on SDRAM controller reset */
245     if (s->scu->regs[reset_ctrl_reg] & SCU_RESET_SDRAM) {
246         timer_del(s->timer);
247         s->regs[WDT_CTRL] = 0;
248         return;
249     }
250 
251     qemu_log_mask(CPU_LOG_RESET, "Watchdog timer %" HWADDR_PRIx " expired.\n",
252                   s->iomem.addr);
253     watchdog_perform_action();
254     timer_del(s->timer);
255 }
256 
257 #define PCLK_HZ 24000000
258 
259 static void aspeed_wdt_realize(DeviceState *dev, Error **errp)
260 {
261     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
262     AspeedWDTState *s = ASPEED_WDT(dev);
263 
264     assert(s->scu);
265 
266     s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, aspeed_wdt_timer_expired, dev);
267 
268     /* FIXME: This setting should be derived from the SCU hw strapping
269      * register SCU70
270      */
271     s->pclk_freq = PCLK_HZ;
272 
273     memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_wdt_ops, s,
274                           TYPE_ASPEED_WDT, ASPEED_WDT_REGS_MAX * 4);
275     sysbus_init_mmio(sbd, &s->iomem);
276 }
277 
278 static Property aspeed_wdt_properties[] = {
279     DEFINE_PROP_LINK("scu", AspeedWDTState, scu, TYPE_ASPEED_SCU,
280                      AspeedSCUState *),
281     DEFINE_PROP_END_OF_LIST(),
282 };
283 
284 static void aspeed_wdt_class_init(ObjectClass *klass, void *data)
285 {
286     DeviceClass *dc = DEVICE_CLASS(klass);
287 
288     dc->desc = "ASPEED Watchdog Controller";
289     dc->realize = aspeed_wdt_realize;
290     dc->reset = aspeed_wdt_reset;
291     set_bit(DEVICE_CATEGORY_WATCHDOG, dc->categories);
292     dc->vmsd = &vmstate_aspeed_wdt;
293     device_class_set_props(dc, aspeed_wdt_properties);
294     dc->desc = "Aspeed watchdog device";
295 }
296 
297 static const TypeInfo aspeed_wdt_info = {
298     .parent = TYPE_SYS_BUS_DEVICE,
299     .name  = TYPE_ASPEED_WDT,
300     .instance_size  = sizeof(AspeedWDTState),
301     .class_init = aspeed_wdt_class_init,
302     .class_size    = sizeof(AspeedWDTClass),
303     .abstract      = true,
304 };
305 
306 static void aspeed_2400_wdt_class_init(ObjectClass *klass, void *data)
307 {
308     DeviceClass *dc = DEVICE_CLASS(klass);
309     AspeedWDTClass *awc = ASPEED_WDT_CLASS(klass);
310 
311     dc->desc = "ASPEED 2400 Watchdog Controller";
312     awc->offset = 0x20;
313     awc->ext_pulse_width_mask = 0xff;
314     awc->reset_ctrl_reg = SCU_RESET_CONTROL1;
315     awc->wdt_reload = aspeed_wdt_reload;
316     awc->sanitize_ctrl = aspeed_2400_sanitize_ctrl;
317     awc->default_status = 0x03EF1480;
318     awc->default_reload_value = 0x03EF1480;
319 }
320 
321 static const TypeInfo aspeed_2400_wdt_info = {
322     .name = TYPE_ASPEED_2400_WDT,
323     .parent = TYPE_ASPEED_WDT,
324     .instance_size = sizeof(AspeedWDTState),
325     .class_init = aspeed_2400_wdt_class_init,
326 };
327 
328 static void aspeed_2500_wdt_reset_pulse(AspeedWDTState *s, uint32_t property)
329 {
330     if (property) {
331         if (property == WDT_ACTIVE_HIGH_MAGIC) {
332             s->regs[WDT_RESET_WIDTH] |= WDT_RESET_WIDTH_ACTIVE_HIGH;
333         } else if (property == WDT_ACTIVE_LOW_MAGIC) {
334             s->regs[WDT_RESET_WIDTH] &= ~WDT_RESET_WIDTH_ACTIVE_HIGH;
335         } else if (property == WDT_PUSH_PULL_MAGIC) {
336             s->regs[WDT_RESET_WIDTH] |= WDT_RESET_WIDTH_PUSH_PULL;
337         } else if (property == WDT_OPEN_DRAIN_MAGIC) {
338             s->regs[WDT_RESET_WIDTH] &= ~WDT_RESET_WIDTH_PUSH_PULL;
339         }
340     }
341 }
342 
343 static void aspeed_2500_wdt_class_init(ObjectClass *klass, void *data)
344 {
345     DeviceClass *dc = DEVICE_CLASS(klass);
346     AspeedWDTClass *awc = ASPEED_WDT_CLASS(klass);
347 
348     dc->desc = "ASPEED 2500 Watchdog Controller";
349     awc->offset = 0x20;
350     awc->ext_pulse_width_mask = 0xfffff;
351     awc->reset_ctrl_reg = SCU_RESET_CONTROL1;
352     awc->reset_pulse = aspeed_2500_wdt_reset_pulse;
353     awc->wdt_reload = aspeed_wdt_reload_1mhz;
354     awc->sanitize_ctrl = aspeed_2500_sanitize_ctrl;
355     awc->default_status = 0x014FB180;
356     awc->default_reload_value = 0x014FB180;
357 }
358 
359 static const TypeInfo aspeed_2500_wdt_info = {
360     .name = TYPE_ASPEED_2500_WDT,
361     .parent = TYPE_ASPEED_WDT,
362     .instance_size = sizeof(AspeedWDTState),
363     .class_init = aspeed_2500_wdt_class_init,
364 };
365 
366 static void aspeed_2600_wdt_class_init(ObjectClass *klass, void *data)
367 {
368     DeviceClass *dc = DEVICE_CLASS(klass);
369     AspeedWDTClass *awc = ASPEED_WDT_CLASS(klass);
370 
371     dc->desc = "ASPEED 2600 Watchdog Controller";
372     awc->offset = 0x40;
373     awc->ext_pulse_width_mask = 0xfffff; /* TODO */
374     awc->reset_ctrl_reg = AST2600_SCU_RESET_CONTROL1;
375     awc->reset_pulse = aspeed_2500_wdt_reset_pulse;
376     awc->wdt_reload = aspeed_wdt_reload_1mhz;
377     awc->sanitize_ctrl = aspeed_2600_sanitize_ctrl;
378     awc->default_status = 0x014FB180;
379     awc->default_reload_value = 0x014FB180;
380 }
381 
382 static const TypeInfo aspeed_2600_wdt_info = {
383     .name = TYPE_ASPEED_2600_WDT,
384     .parent = TYPE_ASPEED_WDT,
385     .instance_size = sizeof(AspeedWDTState),
386     .class_init = aspeed_2600_wdt_class_init,
387 };
388 
389 static void aspeed_1030_wdt_class_init(ObjectClass *klass, void *data)
390 {
391     DeviceClass *dc = DEVICE_CLASS(klass);
392     AspeedWDTClass *awc = ASPEED_WDT_CLASS(klass);
393 
394     dc->desc = "ASPEED 1030 Watchdog Controller";
395     awc->offset = 0x80;
396     awc->ext_pulse_width_mask = 0xfffff; /* TODO */
397     awc->reset_ctrl_reg = AST2600_SCU_RESET_CONTROL1;
398     awc->reset_pulse = aspeed_2500_wdt_reset_pulse;
399     awc->wdt_reload = aspeed_wdt_reload_1mhz;
400     awc->sanitize_ctrl = aspeed_2600_sanitize_ctrl;
401     awc->default_status = 0x014FB180;
402     awc->default_reload_value = 0x014FB180;
403 }
404 
405 static const TypeInfo aspeed_1030_wdt_info = {
406     .name = TYPE_ASPEED_1030_WDT,
407     .parent = TYPE_ASPEED_WDT,
408     .instance_size = sizeof(AspeedWDTState),
409     .class_init = aspeed_1030_wdt_class_init,
410 };
411 
412 static void wdt_aspeed_register_types(void)
413 {
414     type_register_static(&aspeed_wdt_info);
415     type_register_static(&aspeed_2400_wdt_info);
416     type_register_static(&aspeed_2500_wdt_info);
417     type_register_static(&aspeed_2600_wdt_info);
418     type_register_static(&aspeed_1030_wdt_info);
419 }
420 
421 type_init(wdt_aspeed_register_types)
422