qemu/hw/sd/bcm2835_sdhost.c
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   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
 102static 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
 110static 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
 148error:
 149    s->cmd |= SDCMD_FAIL_FLAG;
 150    s->status |= SDHSTS_CMD_TIME_OUT;
 151}
 152
 153static 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
 166static 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
 180static 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_data(&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_data(&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
 256static 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
 310static 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
 372static const MemoryRegionOps bcm2835_sdhost_ops = {
 373    .read = bcm2835_sdhost_read,
 374    .write = bcm2835_sdhost_write,
 375    .endianness = DEVICE_NATIVE_ENDIAN,
 376};
 377
 378static 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
 400static 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
 413static 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
 429static 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
 437static 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
 445static const TypeInfo bcm2835_sdhost_bus_info = {
 446    .name = TYPE_BCM2835_SDHOST_BUS,
 447    .parent = TYPE_SD_BUS,
 448    .instance_size = sizeof(SDBus),
 449};
 450
 451static void bcm2835_sdhost_register_types(void)
 452{
 453    type_register_static(&bcm2835_sdhost_info);
 454    type_register_static(&bcm2835_sdhost_bus_info);
 455}
 456
 457type_init(bcm2835_sdhost_register_types)
 458