1/*
2 * Raspberry Pi (BCM2835) GPIO Controller
3 *
4 * Copyright (c) 2017 Antfield SAS
5 *
6 * Authors:
7 * Clement Deschamps <clement.deschamps@antfield.fr>
8 * Luc Michel <luc.michel@antfield.fr>
9 *
10 * This work is licensed under the terms of the GNU GPL, version 2 or later.
11 * See the COPYING file in the top-level directory.
12 */
13
14#include "qemu/osdep.h"
15#include "qemu/log.h"
16#include "qemu/module.h"
17#include "qemu/timer.h"
18#include "qapi/error.h"
19#include "hw/sysbus.h"
20#include "migration/vmstate.h"
21#include "hw/sd/sd.h"
22#include "hw/gpio/bcm2835_gpio.h"
23#include "hw/irq.h"
24
25#define GPFSEL0 0x00
26#define GPFSEL1 0x04
27#define GPFSEL2 0x08
28#define GPFSEL3 0x0C
29#define GPFSEL4 0x10
30#define GPFSEL5 0x14
31#define GPSET0 0x1C
32#define GPSET1 0x20
33#define GPCLR0 0x28
34#define GPCLR1 0x2C
35#define GPLEV0 0x34
36#define GPLEV1 0x38
37#define GPEDS0 0x40
38#define GPEDS1 0x44
39#define GPREN0 0x4C
40#define GPREN1 0x50
41#define GPFEN0 0x58
42#define GPFEN1 0x5C
43#define GPHEN0 0x64
44#define GPHEN1 0x68
45#define GPLEN0 0x70
46#define GPLEN1 0x74
47#define GPAREN0 0x7C
48#define GPAREN1 0x80
49#define GPAFEN0 0x88
50#define GPAFEN1 0x8C
51#define GPPUD 0x94
52#define GPPUDCLK0 0x98
53#define GPPUDCLK1 0x9C
54
55static uint32_t gpfsel_get(BCM2835GpioState *s, uint8_t reg)
56{
57 int i;
58 uint32_t value = 0;
59 for (i = 0; i < 10; i++) {
60 uint32_t index = 10 * reg + i;
61 if (index < sizeof(s->fsel)) {
62 value |= (s->fsel[index] & 0x7) << (3 * i);
63 }
64 }
65 return value;
66}
67
68static void gpfsel_set(BCM2835GpioState *s, uint8_t reg, uint32_t value)
69{
70 int i;
71 for (i = 0; i < 10; i++) {
72 uint32_t index = 10 * reg + i;
73 if (index < sizeof(s->fsel)) {
74 int fsel = (value >> (3 * i)) & 0x7;
75 s->fsel[index] = fsel;
76 }
77 }
78
79 /* SD controller selection (48-53) */
80 if (s->sd_fsel != 0
81 && (s->fsel[48] == 0) /* SD_CLK_R */
82 && (s->fsel[49] == 0) /* SD_CMD_R */
83 && (s->fsel[50] == 0) /* SD_DATA0_R */
84 && (s->fsel[51] == 0) /* SD_DATA1_R */
85 && (s->fsel[52] == 0) /* SD_DATA2_R */
86 && (s->fsel[53] == 0) /* SD_DATA3_R */
87 ) {
88 /* SDHCI controller selected */
89 sdbus_reparent_card(s->sdbus_sdhost, s->sdbus_sdhci);
90 s->sd_fsel = 0;
91 } else if (s->sd_fsel != 4
92 && (s->fsel[48] == 4) /* SD_CLK_R */
93 && (s->fsel[49] == 4) /* SD_CMD_R */
94 && (s->fsel[50] == 4) /* SD_DATA0_R */
95 && (s->fsel[51] == 4) /* SD_DATA1_R */
96 && (s->fsel[52] == 4) /* SD_DATA2_R */
97 && (s->fsel[53] == 4) /* SD_DATA3_R */
98 ) {
99 /* SDHost controller selected */
100 sdbus_reparent_card(s->sdbus_sdhci, s->sdbus_sdhost);
101 s->sd_fsel = 4;
102 }
103}
104
105static int gpfsel_is_out(BCM2835GpioState *s, int index)
106{
107 if (index >= 0 && index < 54) {
108 return s->fsel[index] == 1;
109 }
110 return 0;
111}
112
113static void gpset(BCM2835GpioState *s,
114 uint32_t val, uint8_t start, uint8_t count, uint32_t *lev)
115{
116 uint32_t changes = val & ~*lev;
117 uint32_t cur = 1;
118
119 int i;
120 for (i = 0; i < count; i++) {
121 if ((changes & cur) && (gpfsel_is_out(s, start + i))) {
122 qemu_set_irq(s->out[start + i], 1);
123 }
124 cur <<= 1;
125 }
126
127 *lev |= val;
128}
129
130static void gpclr(BCM2835GpioState *s,
131 uint32_t val, uint8_t start, uint8_t count, uint32_t *lev)
132{
133 uint32_t changes = val & *lev;
134 uint32_t cur = 1;
135
136 int i;
137 for (i = 0; i < count; i++) {
138 if ((changes & cur) && (gpfsel_is_out(s, start + i))) {
139 qemu_set_irq(s->out[start + i], 0);
140 }
141 cur <<= 1;
142 }
143
144 *lev &= ~val;
145}
146
147static uint64_t bcm2835_gpio_read(void *opaque, hwaddr offset,
148 unsigned size)
149{
150 BCM2835GpioState *s = (BCM2835GpioState *)opaque;
151
152 switch (offset) {
153 case GPFSEL0:
154 case GPFSEL1:
155 case GPFSEL2:
156 case GPFSEL3:
157 case GPFSEL4:
158 case GPFSEL5:
159 return gpfsel_get(s, offset / 4);
160 case GPSET0:
161 case GPSET1:
162 /* Write Only */
163 return 0;
164 case GPCLR0:
165 case GPCLR1:
166 /* Write Only */
167 return 0;
168 case GPLEV0:
169 return s->lev0;
170 case GPLEV1:
171 return s->lev1;
172 case GPEDS0:
173 case GPEDS1:
174 case GPREN0:
175 case GPREN1:
176 case GPFEN0:
177 case GPFEN1:
178 case GPHEN0:
179 case GPHEN1:
180 case GPLEN0:
181 case GPLEN1:
182 case GPAREN0:
183 case GPAREN1:
184 case GPAFEN0:
185 case GPAFEN1:
186 case GPPUD:
187 case GPPUDCLK0:
188 case GPPUDCLK1:
189 /* Not implemented */
190 return 0;
191 default:
192 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
193 __func__, offset);
194 break;
195 }
196
197 return 0;
198}
199
200static void bcm2835_gpio_write(void *opaque, hwaddr offset,
201 uint64_t value, unsigned size)
202{
203 BCM2835GpioState *s = (BCM2835GpioState *)opaque;
204
205 switch (offset) {
206 case GPFSEL0:
207 case GPFSEL1:
208 case GPFSEL2:
209 case GPFSEL3:
210 case GPFSEL4:
211 case GPFSEL5:
212 gpfsel_set(s, offset / 4, value);
213 break;
214 case GPSET0:
215 gpset(s, value, 0, 32, &s->lev0);
216 break;
217 case GPSET1:
218 gpset(s, value, 32, 22, &s->lev1);
219 break;
220 case GPCLR0:
221 gpclr(s, value, 0, 32, &s->lev0);
222 break;
223 case GPCLR1:
224 gpclr(s, value, 32, 22, &s->lev1);
225 break;
226 case GPLEV0:
227 case GPLEV1:
228 /* Read Only */
229 break;
230 case GPEDS0:
231 case GPEDS1:
232 case GPREN0:
233 case GPREN1:
234 case GPFEN0:
235 case GPFEN1:
236 case GPHEN0:
237 case GPHEN1:
238 case GPLEN0:
239 case GPLEN1:
240 case GPAREN0:
241 case GPAREN1:
242 case GPAFEN0:
243 case GPAFEN1:
244 case GPPUD:
245 case GPPUDCLK0:
246 case GPPUDCLK1:
247 /* Not implemented */
248 break;
249 default:
250 goto err_out;
251 }
252 return;
253
254err_out:
255 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
256 __func__, offset);
257}
258
259static void bcm2835_gpio_reset(DeviceState *dev)
260{
261 BCM2835GpioState *s = BCM2835_GPIO(dev);
262
263 int i;
264 for (i = 0; i < 6; i++) {
265 gpfsel_set(s, i, 0);
266 }
267
268 s->sd_fsel = 0;
269
270 /* SDHCI is selected by default */
271 sdbus_reparent_card(&s->sdbus, s->sdbus_sdhci);
272
273 s->lev0 = 0;
274 s->lev1 = 0;
275}
276
277static const MemoryRegionOps bcm2835_gpio_ops = {
278 .read = bcm2835_gpio_read,
279 .write = bcm2835_gpio_write,
280 .endianness = DEVICE_NATIVE_ENDIAN,
281};
282
283static const VMStateDescription vmstate_bcm2835_gpio = {
284 .name = "bcm2835_gpio",
285 .version_id = 1,
286 .minimum_version_id = 1,
287 .fields = (VMStateField[]) {
288 VMSTATE_UINT8_ARRAY(fsel, BCM2835GpioState, 54),
289 VMSTATE_UINT32(lev0, BCM2835GpioState),
290 VMSTATE_UINT32(lev1, BCM2835GpioState),
291 VMSTATE_UINT8(sd_fsel, BCM2835GpioState),
292 VMSTATE_END_OF_LIST()
293 }
294};
295
296static void bcm2835_gpio_init(Object *obj)
297{
298 BCM2835GpioState *s = BCM2835_GPIO(obj);
299 DeviceState *dev = DEVICE(obj);
300 SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
301
302 qbus_create_inplace(&s->sdbus, sizeof(s->sdbus),
303 TYPE_SD_BUS, DEVICE(s), "sd-bus");
304
305 memory_region_init_io(&s->iomem, obj,
306 &bcm2835_gpio_ops, s, "bcm2835_gpio", 0x1000);
307 sysbus_init_mmio(sbd, &s->iomem);
308 qdev_init_gpio_out(dev, s->out, 54);
309}
310
311static void bcm2835_gpio_realize(DeviceState *dev, Error **errp)
312{
313 BCM2835GpioState *s = BCM2835_GPIO(dev);
314 Object *obj;
315 Error *err = NULL;
316
317 obj = object_property_get_link(OBJECT(dev), "sdbus-sdhci", &err);
318 if (obj == NULL) {
319 error_setg(errp, "%s: required sdhci link not found: %s",
320 __func__, error_get_pretty(err));
321 return;
322 }
323 s->sdbus_sdhci = SD_BUS(obj);
324
325 obj = object_property_get_link(OBJECT(dev), "sdbus-sdhost", &err);
326 if (obj == NULL) {
327 error_setg(errp, "%s: required sdhost link not found: %s",
328 __func__, error_get_pretty(err));
329 return;
330 }
331 s->sdbus_sdhost = SD_BUS(obj);
332}
333
334static void bcm2835_gpio_class_init(ObjectClass *klass, void *data)
335{
336 DeviceClass *dc = DEVICE_CLASS(klass);
337
338 dc->vmsd = &vmstate_bcm2835_gpio;
339 dc->realize = &bcm2835_gpio_realize;
340 dc->reset = &bcm2835_gpio_reset;
341}
342
343static const TypeInfo bcm2835_gpio_info = {
344 .name = TYPE_BCM2835_GPIO,
345 .parent = TYPE_SYS_BUS_DEVICE,
346 .instance_size = sizeof(BCM2835GpioState),
347 .instance_init = bcm2835_gpio_init,
348 .class_init = bcm2835_gpio_class_init,
349};
350
351static void bcm2835_gpio_register_types(void)
352{
353 type_register_static(&bcm2835_gpio_info);
354}
355
356type_init(bcm2835_gpio_register_types)
357