1/*
2 * sifive System-on-Chip general purpose input/output register definition
3 *
4 * Copyright 2019 AdaCore
5 *
6 * Base on nrf51_gpio.c:
7 *
8 * Copyright 2018 Steffen Görtz <contrib@steffen-goertz.de>
9 *
10 * This code is licensed under the GPL version 2 or later. See
11 * the COPYING file in the top-level directory.
12 */
13
14#include "qemu/osdep.h"
15#include "qemu/log.h"
16#include "hw/irq.h"
17#include "hw/riscv/sifive_gpio.h"
18#include "migration/vmstate.h"
19#include "trace.h"
20
21static void update_output_irq(SIFIVEGPIOState *s)
22{
23
24 uint32_t pending;
25 uint32_t pin;
26
27 pending = s->high_ip & s->high_ie;
28 pending |= s->low_ip & s->low_ie;
29 pending |= s->rise_ip & s->rise_ie;
30 pending |= s->fall_ip & s->fall_ie;
31
32 for (int i = 0; i < SIFIVE_GPIO_PINS; i++) {
33 pin = 1 << i;
34 qemu_set_irq(s->irq[i], (pending & pin) != 0);
35 trace_sifive_gpio_update_output_irq(i, (pending & pin) != 0);
36 }
37}
38
39static void update_state(SIFIVEGPIOState *s)
40{
41 size_t i;
42 bool prev_ival, in, in_mask, port, out_xor, pull, output_en, input_en,
43 rise_ip, fall_ip, low_ip, high_ip, oval, actual_value, ival;
44
45 for (i = 0; i < SIFIVE_GPIO_PINS; i++) {
46
47 prev_ival = extract32(s->value, i, 1);
48 in = extract32(s->in, i, 1);
49 in_mask = extract32(s->in_mask, i, 1);
50 port = extract32(s->port, i, 1);
51 out_xor = extract32(s->out_xor, i, 1);
52 pull = extract32(s->pue, i, 1);
53 output_en = extract32(s->output_en, i, 1);
54 input_en = extract32(s->input_en, i, 1);
55 rise_ip = extract32(s->rise_ip, i, 1);
56 fall_ip = extract32(s->fall_ip, i, 1);
57 low_ip = extract32(s->low_ip, i, 1);
58 high_ip = extract32(s->high_ip, i, 1);
59
60 /* Output value (IOF not supported) */
61 oval = output_en && (port ^ out_xor);
62
63 /* Pin both driven externally and internally */
64 if (output_en && in_mask) {
65 qemu_log_mask(LOG_GUEST_ERROR, "GPIO pin %zu short circuited\n", i);
66 }
67
68 if (in_mask) {
69 /* The pin is driven by external device */
70 actual_value = in;
71 } else if (output_en) {
72 /* The pin is driven by internal circuit */
73 actual_value = oval;
74 } else {
75 /* Floating? Apply pull-up resistor */
76 actual_value = pull;
77 }
78
79 qemu_set_irq(s->output[i], actual_value);
80
81 /* Input value */
82 ival = input_en && actual_value;
83
84 /* Interrupts */
85 high_ip = high_ip || ival;
86 s->high_ip = deposit32(s->high_ip, i, 1, high_ip);
87
88 low_ip = low_ip || !ival;
89 s->low_ip = deposit32(s->low_ip, i, 1, low_ip);
90
91 rise_ip = rise_ip || (ival && !prev_ival);
92 s->rise_ip = deposit32(s->rise_ip, i, 1, rise_ip);
93
94 fall_ip = fall_ip || (!ival && prev_ival);
95 s->fall_ip = deposit32(s->fall_ip, i, 1, fall_ip);
96
97 /* Update value */
98 s->value = deposit32(s->value, i, 1, ival);
99 }
100 update_output_irq(s);
101}
102
103static uint64_t sifive_gpio_read(void *opaque, hwaddr offset, unsigned int size)
104{
105 SIFIVEGPIOState *s = SIFIVE_GPIO(opaque);
106 uint64_t r = 0;
107
108 switch (offset) {
109 case SIFIVE_GPIO_REG_VALUE:
110 r = s->value;
111 break;
112
113 case SIFIVE_GPIO_REG_INPUT_EN:
114 r = s->input_en;
115 break;
116
117 case SIFIVE_GPIO_REG_OUTPUT_EN:
118 r = s->output_en;
119 break;
120
121 case SIFIVE_GPIO_REG_PORT:
122 r = s->port;
123 break;
124
125 case SIFIVE_GPIO_REG_PUE:
126 r = s->pue;
127 break;
128
129 case SIFIVE_GPIO_REG_DS:
130 r = s->ds;
131 break;
132
133 case SIFIVE_GPIO_REG_RISE_IE:
134 r = s->rise_ie;
135 break;
136
137 case SIFIVE_GPIO_REG_RISE_IP:
138 r = s->rise_ip;
139 break;
140
141 case SIFIVE_GPIO_REG_FALL_IE:
142 r = s->fall_ie;
143 break;
144
145 case SIFIVE_GPIO_REG_FALL_IP:
146 r = s->fall_ip;
147 break;
148
149 case SIFIVE_GPIO_REG_HIGH_IE:
150 r = s->high_ie;
151 break;
152
153 case SIFIVE_GPIO_REG_HIGH_IP:
154 r = s->high_ip;
155 break;
156
157 case SIFIVE_GPIO_REG_LOW_IE:
158 r = s->low_ie;
159 break;
160
161 case SIFIVE_GPIO_REG_LOW_IP:
162 r = s->low_ip;
163 break;
164
165 case SIFIVE_GPIO_REG_IOF_EN:
166 r = s->iof_en;
167 break;
168
169 case SIFIVE_GPIO_REG_IOF_SEL:
170 r = s->iof_sel;
171 break;
172
173 case SIFIVE_GPIO_REG_OUT_XOR:
174 r = s->out_xor;
175 break;
176
177 default:
178 qemu_log_mask(LOG_GUEST_ERROR,
179 "%s: bad read offset 0x%" HWADDR_PRIx "\n",
180 __func__, offset);
181 }
182
183 trace_sifive_gpio_read(offset, r);
184
185 return r;
186}
187
188static void sifive_gpio_write(void *opaque, hwaddr offset,
189 uint64_t value, unsigned int size)
190{
191 SIFIVEGPIOState *s = SIFIVE_GPIO(opaque);
192
193 trace_sifive_gpio_write(offset, value);
194
195 switch (offset) {
196
197 case SIFIVE_GPIO_REG_INPUT_EN:
198 s->input_en = value;
199 break;
200
201 case SIFIVE_GPIO_REG_OUTPUT_EN:
202 s->output_en = value;
203 break;
204
205 case SIFIVE_GPIO_REG_PORT:
206 s->port = value;
207 break;
208
209 case SIFIVE_GPIO_REG_PUE:
210 s->pue = value;
211 break;
212
213 case SIFIVE_GPIO_REG_DS:
214 s->ds = value;
215 break;
216
217 case SIFIVE_GPIO_REG_RISE_IE:
218 s->rise_ie = value;
219 break;
220
221 case SIFIVE_GPIO_REG_RISE_IP:
222 /* Write 1 to clear */
223 s->rise_ip &= ~value;
224 break;
225
226 case SIFIVE_GPIO_REG_FALL_IE:
227 s->fall_ie = value;
228 break;
229
230 case SIFIVE_GPIO_REG_FALL_IP:
231 /* Write 1 to clear */
232 s->fall_ip &= ~value;
233 break;
234
235 case SIFIVE_GPIO_REG_HIGH_IE:
236 s->high_ie = value;
237 break;
238
239 case SIFIVE_GPIO_REG_HIGH_IP:
240 /* Write 1 to clear */
241 s->high_ip &= ~value;
242 break;
243
244 case SIFIVE_GPIO_REG_LOW_IE:
245 s->low_ie = value;
246 break;
247
248 case SIFIVE_GPIO_REG_LOW_IP:
249 /* Write 1 to clear */
250 s->low_ip &= ~value;
251 break;
252
253 case SIFIVE_GPIO_REG_IOF_EN:
254 s->iof_en = value;
255 break;
256
257 case SIFIVE_GPIO_REG_IOF_SEL:
258 s->iof_sel = value;
259 break;
260
261 case SIFIVE_GPIO_REG_OUT_XOR:
262 s->out_xor = value;
263 break;
264
265 default:
266 qemu_log_mask(LOG_GUEST_ERROR,
267 "%s: bad write offset 0x%" HWADDR_PRIx "\n",
268 __func__, offset);
269 }
270
271 update_state(s);
272}
273
274static const MemoryRegionOps gpio_ops = {
275 .read = sifive_gpio_read,
276 .write = sifive_gpio_write,
277 .endianness = DEVICE_LITTLE_ENDIAN,
278 .impl.min_access_size = 4,
279 .impl.max_access_size = 4,
280};
281
282static void sifive_gpio_set(void *opaque, int line, int value)
283{
284 SIFIVEGPIOState *s = SIFIVE_GPIO(opaque);
285
286 trace_sifive_gpio_set(line, value);
287
288 assert(line >= 0 && line < SIFIVE_GPIO_PINS);
289
290 s->in_mask = deposit32(s->in_mask, line, 1, value >= 0);
291 if (value >= 0) {
292 s->in = deposit32(s->in, line, 1, value != 0);
293 }
294
295 update_state(s);
296}
297
298static void sifive_gpio_reset(DeviceState *dev)
299{
300 SIFIVEGPIOState *s = SIFIVE_GPIO(dev);
301
302 s->value = 0;
303 s->input_en = 0;
304 s->output_en = 0;
305 s->port = 0;
306 s->pue = 0;
307 s->ds = 0;
308 s->rise_ie = 0;
309 s->rise_ip = 0;
310 s->fall_ie = 0;
311 s->fall_ip = 0;
312 s->high_ie = 0;
313 s->high_ip = 0;
314 s->low_ie = 0;
315 s->low_ip = 0;
316 s->iof_en = 0;
317 s->iof_sel = 0;
318 s->out_xor = 0;
319 s->in = 0;
320 s->in_mask = 0;
321
322}
323
324static const VMStateDescription vmstate_sifive_gpio = {
325 .name = TYPE_SIFIVE_GPIO,
326 .version_id = 1,
327 .minimum_version_id = 1,
328 .fields = (VMStateField[]) {
329 VMSTATE_UINT32(value, SIFIVEGPIOState),
330 VMSTATE_UINT32(input_en, SIFIVEGPIOState),
331 VMSTATE_UINT32(output_en, SIFIVEGPIOState),
332 VMSTATE_UINT32(port, SIFIVEGPIOState),
333 VMSTATE_UINT32(pue, SIFIVEGPIOState),
334 VMSTATE_UINT32(rise_ie, SIFIVEGPIOState),
335 VMSTATE_UINT32(rise_ip, SIFIVEGPIOState),
336 VMSTATE_UINT32(fall_ie, SIFIVEGPIOState),
337 VMSTATE_UINT32(fall_ip, SIFIVEGPIOState),
338 VMSTATE_UINT32(high_ie, SIFIVEGPIOState),
339 VMSTATE_UINT32(high_ip, SIFIVEGPIOState),
340 VMSTATE_UINT32(low_ie, SIFIVEGPIOState),
341 VMSTATE_UINT32(low_ip, SIFIVEGPIOState),
342 VMSTATE_UINT32(iof_en, SIFIVEGPIOState),
343 VMSTATE_UINT32(iof_sel, SIFIVEGPIOState),
344 VMSTATE_UINT32(out_xor, SIFIVEGPIOState),
345 VMSTATE_UINT32(in, SIFIVEGPIOState),
346 VMSTATE_UINT32(in_mask, SIFIVEGPIOState),
347 VMSTATE_END_OF_LIST()
348 }
349};
350
351static void sifive_gpio_init(Object *obj)
352{
353 SIFIVEGPIOState *s = SIFIVE_GPIO(obj);
354
355 memory_region_init_io(&s->mmio, obj, &gpio_ops, s,
356 TYPE_SIFIVE_GPIO, SIFIVE_GPIO_SIZE);
357 sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio);
358
359
360 for (int i = 0; i < SIFIVE_GPIO_PINS; i++) {
361 sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->irq[i]);
362 }
363
364 qdev_init_gpio_in(DEVICE(s), sifive_gpio_set, SIFIVE_GPIO_PINS);
365 qdev_init_gpio_out(DEVICE(s), s->output, SIFIVE_GPIO_PINS);
366}
367
368static void sifive_gpio_class_init(ObjectClass *klass, void *data)
369{
370 DeviceClass *dc = DEVICE_CLASS(klass);
371
372 dc->vmsd = &vmstate_sifive_gpio;
373 dc->reset = sifive_gpio_reset;
374 dc->desc = "sifive GPIO";
375}
376
377static const TypeInfo sifive_gpio_info = {
378 .name = TYPE_SIFIVE_GPIO,
379 .parent = TYPE_SYS_BUS_DEVICE,
380 .instance_size = sizeof(SIFIVEGPIOState),
381 .instance_init = sifive_gpio_init,
382 .class_init = sifive_gpio_class_init
383};
384
385static void sifive_gpio_register_types(void)
386{
387 type_register_static(&sifive_gpio_info);
388}
389
390type_init(sifive_gpio_register_types)
391