watchdog/aspeed: fix variable type to store reload value
[qemu.git] / hw / watchdog / wdt_aspeed.c
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/timer.h"
15 #include "sysemu/watchdog.h"
16 #include "hw/misc/aspeed_scu.h"
17 #include "hw/sysbus.h"
18 #include "hw/watchdog/wdt_aspeed.h"
19
20 #define WDT_STATUS (0x00 / 4)
21 #define WDT_RELOAD_VALUE (0x04 / 4)
22 #define WDT_RESTART (0x08 / 4)
23 #define WDT_CTRL (0x0C / 4)
24 #define WDT_CTRL_RESET_MODE_SOC (0x00 << 5)
25 #define WDT_CTRL_RESET_MODE_FULL_CHIP (0x01 << 5)
26 #define WDT_CTRL_1MHZ_CLK BIT(4)
27 #define WDT_CTRL_WDT_EXT BIT(3)
28 #define WDT_CTRL_WDT_INTR BIT(2)
29 #define WDT_CTRL_RESET_SYSTEM BIT(1)
30 #define WDT_CTRL_ENABLE BIT(0)
31 #define WDT_RESET_WIDTH (0x18 / 4)
32 #define WDT_RESET_WIDTH_ACTIVE_HIGH BIT(31)
33 #define WDT_POLARITY_MASK (0xFF << 24)
34 #define WDT_ACTIVE_HIGH_MAGIC (0xA5 << 24)
35 #define WDT_ACTIVE_LOW_MAGIC (0x5A << 24)
36 #define WDT_RESET_WIDTH_PUSH_PULL BIT(30)
37 #define WDT_DRIVE_TYPE_MASK (0xFF << 24)
38 #define WDT_PUSH_PULL_MAGIC (0xA8 << 24)
39 #define WDT_OPEN_DRAIN_MAGIC (0x8A << 24)
40
41 #define WDT_TIMEOUT_STATUS (0x10 / 4)
42 #define WDT_TIMEOUT_CLEAR (0x14 / 4)
43
44 #define WDT_RESTART_MAGIC 0x4755
45
46 static bool aspeed_wdt_is_enabled(const AspeedWDTState *s)
47 {
48 return s->regs[WDT_CTRL] & WDT_CTRL_ENABLE;
49 }
50
51 static bool is_ast2500(const AspeedWDTState *s)
52 {
53 switch (s->silicon_rev) {
54 case AST2500_A0_SILICON_REV:
55 case AST2500_A1_SILICON_REV:
56 return true;
57 case AST2400_A0_SILICON_REV:
58 case AST2400_A1_SILICON_REV:
59 default:
60 break;
61 }
62
63 return false;
64 }
65
66 static uint64_t aspeed_wdt_read(void *opaque, hwaddr offset, unsigned size)
67 {
68 AspeedWDTState *s = ASPEED_WDT(opaque);
69
70 offset >>= 2;
71
72 switch (offset) {
73 case WDT_STATUS:
74 return s->regs[WDT_STATUS];
75 case WDT_RELOAD_VALUE:
76 return s->regs[WDT_RELOAD_VALUE];
77 case WDT_RESTART:
78 qemu_log_mask(LOG_GUEST_ERROR,
79 "%s: read from write-only reg at offset 0x%"
80 HWADDR_PRIx "\n", __func__, offset);
81 return 0;
82 case WDT_CTRL:
83 return s->regs[WDT_CTRL];
84 case WDT_RESET_WIDTH:
85 return s->regs[WDT_RESET_WIDTH];
86 case WDT_TIMEOUT_STATUS:
87 case WDT_TIMEOUT_CLEAR:
88 qemu_log_mask(LOG_UNIMP,
89 "%s: uninmplemented read at offset 0x%" HWADDR_PRIx "\n",
90 __func__, offset);
91 return 0;
92 default:
93 qemu_log_mask(LOG_GUEST_ERROR,
94 "%s: Out-of-bounds read at offset 0x%" HWADDR_PRIx "\n",
95 __func__, offset);
96 return 0;
97 }
98
99 }
100
101 static void aspeed_wdt_reload(AspeedWDTState *s, bool pclk)
102 {
103 uint64_t reload;
104
105 if (pclk) {
106 reload = muldiv64(s->regs[WDT_RELOAD_VALUE], NANOSECONDS_PER_SECOND,
107 s->pclk_freq);
108 } else {
109 reload = s->regs[WDT_RELOAD_VALUE] * 1000ULL;
110 }
111
112 if (aspeed_wdt_is_enabled(s)) {
113 timer_mod(s->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + reload);
114 }
115 }
116
117 static void aspeed_wdt_write(void *opaque, hwaddr offset, uint64_t data,
118 unsigned size)
119 {
120 AspeedWDTState *s = ASPEED_WDT(opaque);
121 bool enable = data & WDT_CTRL_ENABLE;
122
123 offset >>= 2;
124
125 switch (offset) {
126 case WDT_STATUS:
127 qemu_log_mask(LOG_GUEST_ERROR,
128 "%s: write to read-only reg at offset 0x%"
129 HWADDR_PRIx "\n", __func__, offset);
130 break;
131 case WDT_RELOAD_VALUE:
132 s->regs[WDT_RELOAD_VALUE] = data;
133 break;
134 case WDT_RESTART:
135 if ((data & 0xFFFF) == WDT_RESTART_MAGIC) {
136 s->regs[WDT_STATUS] = s->regs[WDT_RELOAD_VALUE];
137 aspeed_wdt_reload(s, !(data & WDT_CTRL_1MHZ_CLK));
138 }
139 break;
140 case WDT_CTRL:
141 if (enable && !aspeed_wdt_is_enabled(s)) {
142 s->regs[WDT_CTRL] = data;
143 aspeed_wdt_reload(s, !(data & WDT_CTRL_1MHZ_CLK));
144 } else if (!enable && aspeed_wdt_is_enabled(s)) {
145 s->regs[WDT_CTRL] = data;
146 timer_del(s->timer);
147 }
148 break;
149 case WDT_RESET_WIDTH:
150 {
151 uint32_t property = data & WDT_POLARITY_MASK;
152
153 if (property && is_ast2500(s)) {
154 if (property == WDT_ACTIVE_HIGH_MAGIC) {
155 s->regs[WDT_RESET_WIDTH] |= WDT_RESET_WIDTH_ACTIVE_HIGH;
156 } else if (property == WDT_ACTIVE_LOW_MAGIC) {
157 s->regs[WDT_RESET_WIDTH] &= ~WDT_RESET_WIDTH_ACTIVE_HIGH;
158 } else if (property == WDT_PUSH_PULL_MAGIC) {
159 s->regs[WDT_RESET_WIDTH] |= WDT_RESET_WIDTH_PUSH_PULL;
160 } else if (property == WDT_OPEN_DRAIN_MAGIC) {
161 s->regs[WDT_RESET_WIDTH] &= ~WDT_RESET_WIDTH_PUSH_PULL;
162 }
163 }
164 s->regs[WDT_RESET_WIDTH] &= ~s->ext_pulse_width_mask;
165 s->regs[WDT_RESET_WIDTH] |= data & s->ext_pulse_width_mask;
166 break;
167 }
168 case WDT_TIMEOUT_STATUS:
169 case WDT_TIMEOUT_CLEAR:
170 qemu_log_mask(LOG_UNIMP,
171 "%s: uninmplemented write at offset 0x%" HWADDR_PRIx "\n",
172 __func__, offset);
173 break;
174 default:
175 qemu_log_mask(LOG_GUEST_ERROR,
176 "%s: Out-of-bounds write at offset 0x%" HWADDR_PRIx "\n",
177 __func__, offset);
178 }
179 return;
180 }
181
182 static WatchdogTimerModel model = {
183 .wdt_name = TYPE_ASPEED_WDT,
184 .wdt_description = "Aspeed watchdog device",
185 };
186
187 static const VMStateDescription vmstate_aspeed_wdt = {
188 .name = "vmstate_aspeed_wdt",
189 .version_id = 0,
190 .minimum_version_id = 0,
191 .fields = (VMStateField[]) {
192 VMSTATE_TIMER_PTR(timer, AspeedWDTState),
193 VMSTATE_UINT32_ARRAY(regs, AspeedWDTState, ASPEED_WDT_REGS_MAX),
194 VMSTATE_END_OF_LIST()
195 }
196 };
197
198 static const MemoryRegionOps aspeed_wdt_ops = {
199 .read = aspeed_wdt_read,
200 .write = aspeed_wdt_write,
201 .endianness = DEVICE_LITTLE_ENDIAN,
202 .valid.min_access_size = 4,
203 .valid.max_access_size = 4,
204 .valid.unaligned = false,
205 };
206
207 static void aspeed_wdt_reset(DeviceState *dev)
208 {
209 AspeedWDTState *s = ASPEED_WDT(dev);
210
211 s->regs[WDT_STATUS] = 0x3EF1480;
212 s->regs[WDT_RELOAD_VALUE] = 0x03EF1480;
213 s->regs[WDT_RESTART] = 0;
214 s->regs[WDT_CTRL] = 0;
215 s->regs[WDT_RESET_WIDTH] = 0xFF;
216
217 timer_del(s->timer);
218 }
219
220 static void aspeed_wdt_timer_expired(void *dev)
221 {
222 AspeedWDTState *s = ASPEED_WDT(dev);
223
224 qemu_log_mask(CPU_LOG_RESET, "Watchdog timer expired.\n");
225 watchdog_perform_action();
226 timer_del(s->timer);
227 }
228
229 #define PCLK_HZ 24000000
230
231 static void aspeed_wdt_realize(DeviceState *dev, Error **errp)
232 {
233 SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
234 AspeedWDTState *s = ASPEED_WDT(dev);
235
236 if (!is_supported_silicon_rev(s->silicon_rev)) {
237 error_setg(errp, "Unknown silicon revision: 0x%" PRIx32,
238 s->silicon_rev);
239 return;
240 }
241
242 switch (s->silicon_rev) {
243 case AST2400_A0_SILICON_REV:
244 case AST2400_A1_SILICON_REV:
245 s->ext_pulse_width_mask = 0xff;
246 break;
247 case AST2500_A0_SILICON_REV:
248 case AST2500_A1_SILICON_REV:
249 s->ext_pulse_width_mask = 0xfffff;
250 break;
251 default:
252 g_assert_not_reached();
253 }
254
255 s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, aspeed_wdt_timer_expired, dev);
256
257 /* FIXME: This setting should be derived from the SCU hw strapping
258 * register SCU70
259 */
260 s->pclk_freq = PCLK_HZ;
261
262 memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_wdt_ops, s,
263 TYPE_ASPEED_WDT, ASPEED_WDT_REGS_MAX * 4);
264 sysbus_init_mmio(sbd, &s->iomem);
265 }
266
267 static Property aspeed_wdt_properties[] = {
268 DEFINE_PROP_UINT32("silicon-rev", AspeedWDTState, silicon_rev, 0),
269 DEFINE_PROP_END_OF_LIST(),
270 };
271
272 static void aspeed_wdt_class_init(ObjectClass *klass, void *data)
273 {
274 DeviceClass *dc = DEVICE_CLASS(klass);
275
276 dc->realize = aspeed_wdt_realize;
277 dc->reset = aspeed_wdt_reset;
278 set_bit(DEVICE_CATEGORY_MISC, dc->categories);
279 dc->vmsd = &vmstate_aspeed_wdt;
280 dc->props = aspeed_wdt_properties;
281 }
282
283 static const TypeInfo aspeed_wdt_info = {
284 .parent = TYPE_SYS_BUS_DEVICE,
285 .name = TYPE_ASPEED_WDT,
286 .instance_size = sizeof(AspeedWDTState),
287 .class_init = aspeed_wdt_class_init,
288 };
289
290 static void wdt_aspeed_register_types(void)
291 {
292 watchdog_add_model(&model);
293 type_register_static(&aspeed_wdt_info);
294 }
295
296 type_init(wdt_aspeed_register_types)