hw/gpio/bcm2835_gpio.c

   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
  55 static 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
  68 static 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
 105 static 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
 113 static 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
 130 static 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
 147 static 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
 200 static 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
 254 err_out:
 255     qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
 256             __func__, offset);
 257 }
 258
 259 static 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
 277 static const MemoryRegionOps bcm2835_gpio_ops = {
 278     .read = bcm2835_gpio_read,
 279     .write = bcm2835_gpio_write,
 280     .endianness = DEVICE_NATIVE_ENDIAN,
 281 };
 282
 283 static const VMStateDescription vmstate_bcm2835_gpio = {
 284     .name = "bcm2835_gpio",
 285     .version_id = 1,
 286     .minimum_version_id = 1,
 287     .fields = (const 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
 296 static 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_init(&s->sdbus, sizeof(s->sdbus), TYPE_SD_BUS, DEVICE(s), "sd-bus");
 303
 304     memory_region_init_io(&s->iomem, obj,
 305             &bcm2835_gpio_ops, s, "bcm2835_gpio", 0x1000);
 306     sysbus_init_mmio(sbd, &s->iomem);
 307     qdev_init_gpio_out(dev, s->out, 54);
 308 }
 309
 310 static void bcm2835_gpio_realize(DeviceState *dev, Error **errp)
 311 {
 312     BCM2835GpioState *s = BCM2835_GPIO(dev);
 313     Object *obj;
 314
 315     obj = object_property_get_link(OBJECT(dev), "sdbus-sdhci", &error_abort);
 316     s->sdbus_sdhci = SD_BUS(obj);
 317
 318     obj = object_property_get_link(OBJECT(dev), "sdbus-sdhost", &error_abort);
 319     s->sdbus_sdhost = SD_BUS(obj);
 320 }
 321
 322 static void bcm2835_gpio_class_init(ObjectClass *klass, void *data)
 323 {
 324     DeviceClass *dc = DEVICE_CLASS(klass);
 325
 326     dc->vmsd = &vmstate_bcm2835_gpio;
 327     dc->realize = &bcm2835_gpio_realize;
 328     dc->reset = &bcm2835_gpio_reset;
 329 }
 330
 331 static const TypeInfo bcm2835_gpio_info = {
 332     .name          = TYPE_BCM2835_GPIO,
 333     .parent        = TYPE_SYS_BUS_DEVICE,
 334     .instance_size = sizeof(BCM2835GpioState),
 335     .instance_init = bcm2835_gpio_init,
 336     .class_init    = bcm2835_gpio_class_init,
 337 };
 338
 339 static void bcm2835_gpio_register_types(void)
 340 {
 341     type_register_static(&bcm2835_gpio_info);
 342 }
 343
 344 type_init(bcm2835_gpio_register_types)