1 /* 2 * Raspberry Pi (BCM2835) SD Host 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 "sysemu/blockdev.h" 18 #include "hw/irq.h" 19 #include "hw/sd/bcm2835_sdhost.h" 20 #include "migration/vmstate.h" 21 #include "trace.h" 22 23 #define TYPE_BCM2835_SDHOST_BUS "bcm2835-sdhost-bus" 24 #define BCM2835_SDHOST_BUS(obj) \ 25 OBJECT_CHECK(SDBus, (obj), TYPE_BCM2835_SDHOST_BUS) 26 27 #define SDCMD 0x00 /* Command to SD card - 16 R/W */ 28 #define SDARG 0x04 /* Argument to SD card - 32 R/W */ 29 #define SDTOUT 0x08 /* Start value for timeout counter - 32 R/W */ 30 #define SDCDIV 0x0c /* Start value for clock divider - 11 R/W */ 31 #define SDRSP0 0x10 /* SD card rsp (31:0) - 32 R */ 32 #define SDRSP1 0x14 /* SD card rsp (63:32) - 32 R */ 33 #define SDRSP2 0x18 /* SD card rsp (95:64) - 32 R */ 34 #define SDRSP3 0x1c /* SD card rsp (127:96) - 32 R */ 35 #define SDHSTS 0x20 /* SD host status - 11 R */ 36 #define SDVDD 0x30 /* SD card power control - 1 R/W */ 37 #define SDEDM 0x34 /* Emergency Debug Mode - 13 R/W */ 38 #define SDHCFG 0x38 /* Host configuration - 2 R/W */ 39 #define SDHBCT 0x3c /* Host byte count (debug) - 32 R/W */ 40 #define SDDATA 0x40 /* Data to/from SD card - 32 R/W */ 41 #define SDHBLC 0x50 /* Host block count (SDIO/SDHC) - 9 R/W */ 42 43 #define SDCMD_NEW_FLAG 0x8000 44 #define SDCMD_FAIL_FLAG 0x4000 45 #define SDCMD_BUSYWAIT 0x800 46 #define SDCMD_NO_RESPONSE 0x400 47 #define SDCMD_LONG_RESPONSE 0x200 48 #define SDCMD_WRITE_CMD 0x80 49 #define SDCMD_READ_CMD 0x40 50 #define SDCMD_CMD_MASK 0x3f 51 52 #define SDCDIV_MAX_CDIV 0x7ff 53 54 #define SDHSTS_BUSY_IRPT 0x400 55 #define SDHSTS_BLOCK_IRPT 0x200 56 #define SDHSTS_SDIO_IRPT 0x100 57 #define SDHSTS_REW_TIME_OUT 0x80 58 #define SDHSTS_CMD_TIME_OUT 0x40 59 #define SDHSTS_CRC16_ERROR 0x20 60 #define SDHSTS_CRC7_ERROR 0x10 61 #define SDHSTS_FIFO_ERROR 0x08 62 /* Reserved */ 63 /* Reserved */ 64 #define SDHSTS_DATA_FLAG 0x01 65 66 #define SDHCFG_BUSY_IRPT_EN (1 << 10) 67 #define SDHCFG_BLOCK_IRPT_EN (1 << 8) 68 #define SDHCFG_SDIO_IRPT_EN (1 << 5) 69 #define SDHCFG_DATA_IRPT_EN (1 << 4) 70 #define SDHCFG_SLOW_CARD (1 << 3) 71 #define SDHCFG_WIDE_EXT_BUS (1 << 2) 72 #define SDHCFG_WIDE_INT_BUS (1 << 1) 73 #define SDHCFG_REL_CMD_LINE (1 << 0) 74 75 #define SDEDM_FORCE_DATA_MODE (1 << 19) 76 #define SDEDM_CLOCK_PULSE (1 << 20) 77 #define SDEDM_BYPASS (1 << 21) 78 79 #define SDEDM_WRITE_THRESHOLD_SHIFT 9 80 #define SDEDM_READ_THRESHOLD_SHIFT 14 81 #define SDEDM_THRESHOLD_MASK 0x1f 82 83 #define SDEDM_FSM_MASK 0xf 84 #define SDEDM_FSM_IDENTMODE 0x0 85 #define SDEDM_FSM_DATAMODE 0x1 86 #define SDEDM_FSM_READDATA 0x2 87 #define SDEDM_FSM_WRITEDATA 0x3 88 #define SDEDM_FSM_READWAIT 0x4 89 #define SDEDM_FSM_READCRC 0x5 90 #define SDEDM_FSM_WRITECRC 0x6 91 #define SDEDM_FSM_WRITEWAIT1 0x7 92 #define SDEDM_FSM_POWERDOWN 0x8 93 #define SDEDM_FSM_POWERUP 0x9 94 #define SDEDM_FSM_WRITESTART1 0xa 95 #define SDEDM_FSM_WRITESTART2 0xb 96 #define SDEDM_FSM_GENPULSES 0xc 97 #define SDEDM_FSM_WRITEWAIT2 0xd 98 #define SDEDM_FSM_STARTPOWDOWN 0xf 99 100 #define SDDATA_FIFO_WORDS 16 101 102 static void bcm2835_sdhost_update_irq(BCM2835SDHostState *s) 103 { 104 uint32_t irq = s->status & 105 (SDHSTS_BUSY_IRPT | SDHSTS_BLOCK_IRPT | SDHSTS_SDIO_IRPT); 106 trace_bcm2835_sdhost_update_irq(irq); 107 qemu_set_irq(s->irq, !!irq); 108 } 109 110 static void bcm2835_sdhost_send_command(BCM2835SDHostState *s) 111 { 112 SDRequest request; 113 uint8_t rsp[16]; 114 int rlen; 115 116 request.cmd = s->cmd & SDCMD_CMD_MASK; 117 request.arg = s->cmdarg; 118 119 rlen = sdbus_do_command(&s->sdbus, &request, rsp); 120 if (rlen < 0) { 121 goto error; 122 } 123 if (!(s->cmd & SDCMD_NO_RESPONSE)) { 124 if (rlen == 0 || (rlen == 4 && (s->cmd & SDCMD_LONG_RESPONSE))) { 125 goto error; 126 } 127 if (rlen != 4 && rlen != 16) { 128 goto error; 129 } 130 if (rlen == 4) { 131 s->rsp[0] = ldl_be_p(&rsp[0]); 132 s->rsp[1] = s->rsp[2] = s->rsp[3] = 0; 133 } else { 134 s->rsp[0] = ldl_be_p(&rsp[12]); 135 s->rsp[1] = ldl_be_p(&rsp[8]); 136 s->rsp[2] = ldl_be_p(&rsp[4]); 137 s->rsp[3] = ldl_be_p(&rsp[0]); 138 } 139 } 140 /* We never really delay commands, so if this was a 'busywait' command 141 * then we've completed it now and can raise the interrupt. 142 */ 143 if ((s->cmd & SDCMD_BUSYWAIT) && (s->config & SDHCFG_BUSY_IRPT_EN)) { 144 s->status |= SDHSTS_BUSY_IRPT; 145 } 146 return; 147 148 error: 149 s->cmd |= SDCMD_FAIL_FLAG; 150 s->status |= SDHSTS_CMD_TIME_OUT; 151 } 152 153 static void bcm2835_sdhost_fifo_push(BCM2835SDHostState *s, uint32_t value) 154 { 155 int n; 156 157 if (s->fifo_len == BCM2835_SDHOST_FIFO_LEN) { 158 /* FIFO overflow */ 159 return; 160 } 161 n = (s->fifo_pos + s->fifo_len) & (BCM2835_SDHOST_FIFO_LEN - 1); 162 s->fifo_len++; 163 s->fifo[n] = value; 164 } 165 166 static uint32_t bcm2835_sdhost_fifo_pop(BCM2835SDHostState *s) 167 { 168 uint32_t value; 169 170 if (s->fifo_len == 0) { 171 /* FIFO underflow */ 172 return 0; 173 } 174 value = s->fifo[s->fifo_pos]; 175 s->fifo_len--; 176 s->fifo_pos = (s->fifo_pos + 1) & (BCM2835_SDHOST_FIFO_LEN - 1); 177 return value; 178 } 179 180 static void bcm2835_sdhost_fifo_run(BCM2835SDHostState *s) 181 { 182 uint32_t value = 0; 183 int n; 184 int is_read; 185 int is_write; 186 187 is_read = (s->cmd & SDCMD_READ_CMD) != 0; 188 is_write = (s->cmd & SDCMD_WRITE_CMD) != 0; 189 if (s->datacnt != 0 && (is_write || sdbus_data_ready(&s->sdbus))) { 190 if (is_read) { 191 n = 0; 192 while (s->datacnt && s->fifo_len < BCM2835_SDHOST_FIFO_LEN) { 193 value |= (uint32_t)sdbus_read_byte(&s->sdbus) << (n * 8); 194 s->datacnt--; 195 n++; 196 if (n == 4) { 197 bcm2835_sdhost_fifo_push(s, value); 198 s->status |= SDHSTS_DATA_FLAG; 199 if (s->config & SDHCFG_DATA_IRPT_EN) { 200 s->status |= SDHSTS_SDIO_IRPT; 201 } 202 n = 0; 203 value = 0; 204 } 205 } 206 if (n != 0) { 207 bcm2835_sdhost_fifo_push(s, value); 208 s->status |= SDHSTS_DATA_FLAG; 209 if (s->config & SDHCFG_DATA_IRPT_EN) { 210 s->status |= SDHSTS_SDIO_IRPT; 211 } 212 } 213 } else if (is_write) { /* write */ 214 n = 0; 215 while (s->datacnt > 0 && (s->fifo_len > 0 || n > 0)) { 216 if (n == 0) { 217 value = bcm2835_sdhost_fifo_pop(s); 218 s->status |= SDHSTS_DATA_FLAG; 219 if (s->config & SDHCFG_DATA_IRPT_EN) { 220 s->status |= SDHSTS_SDIO_IRPT; 221 } 222 n = 4; 223 } 224 n--; 225 s->datacnt--; 226 sdbus_write_byte(&s->sdbus, value & 0xff); 227 value >>= 8; 228 } 229 } 230 if (s->datacnt == 0) { 231 s->edm &= ~SDEDM_FSM_MASK; 232 s->edm |= SDEDM_FSM_DATAMODE; 233 trace_bcm2835_sdhost_edm_change("datacnt 0", s->edm); 234 } 235 if (is_write) { 236 /* set block interrupt at end of each block transfer */ 237 if (s->hbct && s->datacnt % s->hbct == 0 && 238 (s->config & SDHCFG_BLOCK_IRPT_EN)) { 239 s->status |= SDHSTS_BLOCK_IRPT; 240 } 241 /* set data interrupt after each transfer */ 242 s->status |= SDHSTS_DATA_FLAG; 243 if (s->config & SDHCFG_DATA_IRPT_EN) { 244 s->status |= SDHSTS_SDIO_IRPT; 245 } 246 } 247 } 248 249 bcm2835_sdhost_update_irq(s); 250 251 s->edm &= ~(0x1f << 4); 252 s->edm |= ((s->fifo_len & 0x1f) << 4); 253 trace_bcm2835_sdhost_edm_change("fifo run", s->edm); 254 } 255 256 static uint64_t bcm2835_sdhost_read(void *opaque, hwaddr offset, 257 unsigned size) 258 { 259 BCM2835SDHostState *s = (BCM2835SDHostState *)opaque; 260 uint32_t res = 0; 261 262 switch (offset) { 263 case SDCMD: 264 res = s->cmd; 265 break; 266 case SDHSTS: 267 res = s->status; 268 break; 269 case SDRSP0: 270 res = s->rsp[0]; 271 break; 272 case SDRSP1: 273 res = s->rsp[1]; 274 break; 275 case SDRSP2: 276 res = s->rsp[2]; 277 break; 278 case SDRSP3: 279 res = s->rsp[3]; 280 break; 281 case SDEDM: 282 res = s->edm; 283 break; 284 case SDVDD: 285 res = s->vdd; 286 break; 287 case SDDATA: 288 res = bcm2835_sdhost_fifo_pop(s); 289 bcm2835_sdhost_fifo_run(s); 290 break; 291 case SDHBCT: 292 res = s->hbct; 293 break; 294 case SDHBLC: 295 res = s->hblc; 296 break; 297 298 default: 299 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n", 300 __func__, offset); 301 res = 0; 302 break; 303 } 304 305 trace_bcm2835_sdhost_read(offset, res, size); 306 307 return res; 308 } 309 310 static void bcm2835_sdhost_write(void *opaque, hwaddr offset, 311 uint64_t value, unsigned size) 312 { 313 BCM2835SDHostState *s = (BCM2835SDHostState *)opaque; 314 315 trace_bcm2835_sdhost_write(offset, value, size); 316 317 switch (offset) { 318 case SDCMD: 319 s->cmd = value; 320 if (value & SDCMD_NEW_FLAG) { 321 bcm2835_sdhost_send_command(s); 322 bcm2835_sdhost_fifo_run(s); 323 s->cmd &= ~SDCMD_NEW_FLAG; 324 } 325 break; 326 case SDTOUT: 327 break; 328 case SDCDIV: 329 break; 330 case SDHSTS: 331 s->status &= ~value; 332 bcm2835_sdhost_update_irq(s); 333 break; 334 case SDARG: 335 s->cmdarg = value; 336 break; 337 case SDEDM: 338 if ((value & 0xf) == 0xf) { 339 /* power down */ 340 value &= ~0xf; 341 } 342 s->edm = value; 343 trace_bcm2835_sdhost_edm_change("guest register write", s->edm); 344 break; 345 case SDHCFG: 346 s->config = value; 347 bcm2835_sdhost_fifo_run(s); 348 break; 349 case SDVDD: 350 s->vdd = value; 351 break; 352 case SDDATA: 353 bcm2835_sdhost_fifo_push(s, value); 354 bcm2835_sdhost_fifo_run(s); 355 break; 356 case SDHBCT: 357 s->hbct = value; 358 break; 359 case SDHBLC: 360 s->hblc = value; 361 s->datacnt = s->hblc * s->hbct; 362 bcm2835_sdhost_fifo_run(s); 363 break; 364 365 default: 366 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n", 367 __func__, offset); 368 break; 369 } 370 } 371 372 static const MemoryRegionOps bcm2835_sdhost_ops = { 373 .read = bcm2835_sdhost_read, 374 .write = bcm2835_sdhost_write, 375 .endianness = DEVICE_NATIVE_ENDIAN, 376 }; 377 378 static const VMStateDescription vmstate_bcm2835_sdhost = { 379 .name = TYPE_BCM2835_SDHOST, 380 .version_id = 1, 381 .minimum_version_id = 1, 382 .fields = (VMStateField[]) { 383 VMSTATE_UINT32(cmd, BCM2835SDHostState), 384 VMSTATE_UINT32(cmdarg, BCM2835SDHostState), 385 VMSTATE_UINT32(status, BCM2835SDHostState), 386 VMSTATE_UINT32_ARRAY(rsp, BCM2835SDHostState, 4), 387 VMSTATE_UINT32(config, BCM2835SDHostState), 388 VMSTATE_UINT32(edm, BCM2835SDHostState), 389 VMSTATE_UINT32(vdd, BCM2835SDHostState), 390 VMSTATE_UINT32(hbct, BCM2835SDHostState), 391 VMSTATE_UINT32(hblc, BCM2835SDHostState), 392 VMSTATE_INT32(fifo_pos, BCM2835SDHostState), 393 VMSTATE_INT32(fifo_len, BCM2835SDHostState), 394 VMSTATE_UINT32_ARRAY(fifo, BCM2835SDHostState, BCM2835_SDHOST_FIFO_LEN), 395 VMSTATE_UINT32(datacnt, BCM2835SDHostState), 396 VMSTATE_END_OF_LIST() 397 } 398 }; 399 400 static void bcm2835_sdhost_init(Object *obj) 401 { 402 BCM2835SDHostState *s = BCM2835_SDHOST(obj); 403 404 qbus_create_inplace(&s->sdbus, sizeof(s->sdbus), 405 TYPE_BCM2835_SDHOST_BUS, DEVICE(s), "sd-bus"); 406 407 memory_region_init_io(&s->iomem, obj, &bcm2835_sdhost_ops, s, 408 TYPE_BCM2835_SDHOST, 0x1000); 409 sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem); 410 sysbus_init_irq(SYS_BUS_DEVICE(s), &s->irq); 411 } 412 413 static void bcm2835_sdhost_reset(DeviceState *dev) 414 { 415 BCM2835SDHostState *s = BCM2835_SDHOST(dev); 416 417 s->cmd = 0; 418 s->cmdarg = 0; 419 s->edm = 0x0000c60f; 420 trace_bcm2835_sdhost_edm_change("device reset", s->edm); 421 s->config = 0; 422 s->hbct = 0; 423 s->hblc = 0; 424 s->datacnt = 0; 425 s->fifo_pos = 0; 426 s->fifo_len = 0; 427 } 428 429 static void bcm2835_sdhost_class_init(ObjectClass *klass, void *data) 430 { 431 DeviceClass *dc = DEVICE_CLASS(klass); 432 433 dc->reset = bcm2835_sdhost_reset; 434 dc->vmsd = &vmstate_bcm2835_sdhost; 435 } 436 437 static TypeInfo bcm2835_sdhost_info = { 438 .name = TYPE_BCM2835_SDHOST, 439 .parent = TYPE_SYS_BUS_DEVICE, 440 .instance_size = sizeof(BCM2835SDHostState), 441 .class_init = bcm2835_sdhost_class_init, 442 .instance_init = bcm2835_sdhost_init, 443 }; 444 445 static const TypeInfo bcm2835_sdhost_bus_info = { 446 .name = TYPE_BCM2835_SDHOST_BUS, 447 .parent = TYPE_SD_BUS, 448 .instance_size = sizeof(SDBus), 449 }; 450 451 static void bcm2835_sdhost_register_types(void) 452 { 453 type_register_static(&bcm2835_sdhost_info); 454 type_register_static(&bcm2835_sdhost_bus_info); 455 } 456 457 type_init(bcm2835_sdhost_register_types) 458