hw/ssi/ibex_spi_host.c

   1 /*
   2  * QEMU model of the Ibex SPI Controller
   3  * SPEC Reference: https://docs.opentitan.org/hw/ip/spi_host/doc/
   4  *
   5  * Copyright (C) 2022 Western Digital
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  23  * THE SOFTWARE.
  24  */
  25
  26 #include "qemu/osdep.h"
  27 #include "qemu/log.h"
  28 #include "qemu/module.h"
  29 #include "hw/registerfields.h"
  30 #include "hw/ssi/ibex_spi_host.h"
  31 #include "hw/irq.h"
  32 #include "hw/qdev-properties.h"
  33 #include "hw/qdev-properties-system.h"
  34 #include "migration/vmstate.h"
  35 #include "trace.h"
  36
  37 REG32(INTR_STATE, 0x00)
  38     FIELD(INTR_STATE, ERROR, 0, 1)
  39     FIELD(INTR_STATE, SPI_EVENT, 1, 1)
  40 REG32(INTR_ENABLE, 0x04)
  41     FIELD(INTR_ENABLE, ERROR, 0, 1)
  42     FIELD(INTR_ENABLE, SPI_EVENT, 1, 1)
  43 REG32(INTR_TEST, 0x08)
  44     FIELD(INTR_TEST, ERROR, 0, 1)
  45     FIELD(INTR_TEST, SPI_EVENT, 1, 1)
  46 REG32(ALERT_TEST, 0x0c)
  47     FIELD(ALERT_TEST, FETAL_TEST, 0, 1)
  48 REG32(CONTROL, 0x10)
  49     FIELD(CONTROL, RX_WATERMARK, 0, 8)
  50     FIELD(CONTROL, TX_WATERMARK, 1, 8)
  51     FIELD(CONTROL, OUTPUT_EN, 29, 1)
  52     FIELD(CONTROL, SW_RST, 30, 1)
  53     FIELD(CONTROL, SPIEN, 31, 1)
  54 REG32(STATUS, 0x14)
  55     FIELD(STATUS, TXQD, 0, 8)
  56     FIELD(STATUS, RXQD, 18, 8)
  57     FIELD(STATUS, CMDQD, 16, 3)
  58     FIELD(STATUS, RXWM, 20, 1)
  59     FIELD(STATUS, BYTEORDER, 22, 1)
  60     FIELD(STATUS, RXSTALL, 23, 1)
  61     FIELD(STATUS, RXEMPTY, 24, 1)
  62     FIELD(STATUS, RXFULL, 25, 1)
  63     FIELD(STATUS, TXWM, 26, 1)
  64     FIELD(STATUS, TXSTALL, 27, 1)
  65     FIELD(STATUS, TXEMPTY, 28, 1)
  66     FIELD(STATUS, TXFULL, 29, 1)
  67     FIELD(STATUS, ACTIVE, 30, 1)
  68     FIELD(STATUS, READY, 31, 1)
  69 REG32(CONFIGOPTS, 0x18)
  70     FIELD(CONFIGOPTS, CLKDIV_0, 0, 16)
  71     FIELD(CONFIGOPTS, CSNIDLE_0, 16, 4)
  72     FIELD(CONFIGOPTS, CSNTRAIL_0, 20, 4)
  73     FIELD(CONFIGOPTS, CSNLEAD_0, 24, 4)
  74     FIELD(CONFIGOPTS, FULLCYC_0, 29, 1)
  75     FIELD(CONFIGOPTS, CPHA_0, 30, 1)
  76     FIELD(CONFIGOPTS, CPOL_0, 31, 1)
  77 REG32(CSID, 0x1c)
  78     FIELD(CSID, CSID, 0, 32)
  79 REG32(COMMAND, 0x20)
  80     FIELD(COMMAND, LEN, 0, 8)
  81     FIELD(COMMAND, CSAAT, 9, 1)
  82     FIELD(COMMAND, SPEED, 10, 2)
  83     FIELD(COMMAND, DIRECTION, 12, 2)
  84 REG32(ERROR_ENABLE, 0x2c)
  85     FIELD(ERROR_ENABLE, CMDBUSY, 0, 1)
  86     FIELD(ERROR_ENABLE, OVERFLOW, 1, 1)
  87     FIELD(ERROR_ENABLE, UNDERFLOW, 2, 1)
  88     FIELD(ERROR_ENABLE, CMDINVAL, 3, 1)
  89     FIELD(ERROR_ENABLE, CSIDINVAL, 4, 1)
  90 REG32(ERROR_STATUS, 0x30)
  91     FIELD(ERROR_STATUS, CMDBUSY, 0, 1)
  92     FIELD(ERROR_STATUS, OVERFLOW, 1, 1)
  93     FIELD(ERROR_STATUS, UNDERFLOW, 2, 1)
  94     FIELD(ERROR_STATUS, CMDINVAL, 3, 1)
  95     FIELD(ERROR_STATUS, CSIDINVAL, 4, 1)
  96     FIELD(ERROR_STATUS, ACCESSINVAL, 5, 1)
  97 REG32(EVENT_ENABLE, 0x34)
  98     FIELD(EVENT_ENABLE, RXFULL, 0, 1)
  99     FIELD(EVENT_ENABLE, TXEMPTY, 1, 1)
 100     FIELD(EVENT_ENABLE, RXWM, 2, 1)
 101     FIELD(EVENT_ENABLE, TXWM, 3, 1)
 102     FIELD(EVENT_ENABLE, READY, 4, 1)
 103     FIELD(EVENT_ENABLE, IDLE, 5, 1)
 104
 105 static inline uint8_t div4_round_up(uint8_t dividend)
 106 {
 107     return (dividend + 3) / 4;
 108 }
 109
 110 static void ibex_spi_rxfifo_reset(IbexSPIHostState *s)
 111 {
 112     uint32_t data = s->regs[IBEX_SPI_HOST_STATUS];
 113     /* Empty the RX FIFO and assert RXEMPTY */
 114     fifo8_reset(&s->rx_fifo);
 115     data = FIELD_DP32(data, STATUS, RXFULL, 0);
 116     data = FIELD_DP32(data, STATUS, RXEMPTY, 1);
 117     s->regs[IBEX_SPI_HOST_STATUS] = data;
 118 }
 119
 120 static void ibex_spi_txfifo_reset(IbexSPIHostState *s)
 121 {
 122     uint32_t data = s->regs[IBEX_SPI_HOST_STATUS];
 123     /* Empty the TX FIFO and assert TXEMPTY */
 124     fifo8_reset(&s->tx_fifo);
 125     data = FIELD_DP32(data, STATUS, TXFULL, 0);
 126     data = FIELD_DP32(data, STATUS, TXEMPTY, 1);
 127     s->regs[IBEX_SPI_HOST_STATUS] = data;
 128 }
 129
 130 static void ibex_spi_host_reset(DeviceState *dev)
 131 {
 132     IbexSPIHostState *s = IBEX_SPI_HOST(dev);
 133     trace_ibex_spi_host_reset("Resetting Ibex SPI");
 134
 135     /* SPI Host Register Reset */
 136     s->regs[IBEX_SPI_HOST_INTR_STATE]   = 0x00;
 137     s->regs[IBEX_SPI_HOST_INTR_ENABLE]  = 0x00;
 138     s->regs[IBEX_SPI_HOST_INTR_TEST]    = 0x00;
 139     s->regs[IBEX_SPI_HOST_ALERT_TEST]   = 0x00;
 140     s->regs[IBEX_SPI_HOST_CONTROL]      = 0x7f;
 141     s->regs[IBEX_SPI_HOST_STATUS]       = 0x00;
 142     s->regs[IBEX_SPI_HOST_CONFIGOPTS]   = 0x00;
 143     s->regs[IBEX_SPI_HOST_CSID]         = 0x00;
 144     s->regs[IBEX_SPI_HOST_COMMAND]      = 0x00;
 145     /* RX/TX Modelled by FIFO */
 146     s->regs[IBEX_SPI_HOST_RXDATA]       = 0x00;
 147     s->regs[IBEX_SPI_HOST_TXDATA]       = 0x00;
 148
 149     s->regs[IBEX_SPI_HOST_ERROR_ENABLE] = 0x1F;
 150     s->regs[IBEX_SPI_HOST_ERROR_STATUS] = 0x00;
 151     s->regs[IBEX_SPI_HOST_EVENT_ENABLE] = 0x00;
 152
 153     ibex_spi_rxfifo_reset(s);
 154     ibex_spi_txfifo_reset(s);
 155
 156     s->init_status = true;
 157     return;
 158 }
 159
 160 /*
 161  * Check if we need to trigger an interrupt.
 162  * The two interrupts lines (host_err and event) can
 163  * be enabled separately in 'IBEX_SPI_HOST_INTR_ENABLE'.
 164  *
 165  * Interrupts are triggered based on the ones
 166  * enabled in the `IBEX_SPI_HOST_EVENT_ENABLE` and `IBEX_SPI_HOST_ERROR_ENABLE`.
 167  */
 168 static void ibex_spi_host_irq(IbexSPIHostState *s)
 169 {
 170     uint32_t intr_test_reg = s->regs[IBEX_SPI_HOST_INTR_TEST];
 171     uint32_t intr_en_reg = s->regs[IBEX_SPI_HOST_INTR_ENABLE];
 172     uint32_t intr_state_reg = s->regs[IBEX_SPI_HOST_INTR_STATE];
 173
 174     uint32_t err_en_reg = s->regs[IBEX_SPI_HOST_ERROR_ENABLE];
 175     uint32_t event_en_reg = s->regs[IBEX_SPI_HOST_EVENT_ENABLE];
 176     uint32_t err_status_reg = s->regs[IBEX_SPI_HOST_ERROR_STATUS];
 177     uint32_t status_reg = s->regs[IBEX_SPI_HOST_STATUS];
 178
 179
 180     bool error_en = FIELD_EX32(intr_en_reg, INTR_ENABLE, ERROR);
 181     bool event_en = FIELD_EX32(intr_en_reg, INTR_ENABLE, SPI_EVENT);
 182     bool err_pending = FIELD_EX32(intr_state_reg, INTR_STATE, ERROR);
 183     bool status_pending = FIELD_EX32(intr_state_reg, INTR_STATE, SPI_EVENT);
 184
 185     int err_irq = 0, event_irq = 0;
 186
 187     /* Error IRQ enabled and Error IRQ Cleared */
 188     if (error_en && !err_pending) {
 189         /* Event enabled, Interrupt Test Error */
 190         if (FIELD_EX32(intr_test_reg, INTR_TEST,  ERROR)) {
 191             err_irq = 1;
 192         } else if (FIELD_EX32(err_en_reg, ERROR_ENABLE,  CMDBUSY) &&
 193                    FIELD_EX32(err_status_reg, ERROR_STATUS,  CMDBUSY)) {
 194             /* Wrote to COMMAND when not READY */
 195             err_irq = 1;
 196         } else if (FIELD_EX32(err_en_reg, ERROR_ENABLE,  CMDINVAL)  &&
 197                    FIELD_EX32(err_status_reg, ERROR_STATUS,  CMDINVAL)) {
 198             /* Invalid command segment */
 199             err_irq = 1;
 200         } else if (FIELD_EX32(err_en_reg, ERROR_ENABLE,  CSIDINVAL) &&
 201                    FIELD_EX32(err_status_reg, ERROR_STATUS,  CSIDINVAL)) {
 202             /* Invalid value for CSID */
 203             err_irq = 1;
 204         }
 205         if (err_irq) {
 206             s->regs[IBEX_SPI_HOST_INTR_STATE] |= R_INTR_STATE_ERROR_MASK;
 207         }
 208         qemu_set_irq(s->host_err, err_irq);
 209     }
 210
 211     /* Event IRQ Enabled and Event IRQ Cleared */
 212     if (event_en && !status_pending) {
 213         if (FIELD_EX32(intr_test_reg, INTR_STATE,  SPI_EVENT)) {
 214             /* Event enabled, Interrupt Test Event */
 215             event_irq = 1;
 216         } else if (FIELD_EX32(event_en_reg, EVENT_ENABLE,  READY) &&
 217                    FIELD_EX32(status_reg, STATUS, READY)) {
 218             /* SPI Host ready for next command */
 219             event_irq = 1;
 220         } else if (FIELD_EX32(event_en_reg, EVENT_ENABLE,  TXEMPTY) &&
 221                    FIELD_EX32(status_reg, STATUS,  TXEMPTY)) {
 222             /* SPI TXEMPTY, TXFIFO drained */
 223             event_irq = 1;
 224         } else if (FIELD_EX32(event_en_reg, EVENT_ENABLE,  RXFULL) &&
 225                    FIELD_EX32(status_reg, STATUS,  RXFULL)) {
 226             /* SPI RXFULL, RXFIFO  full */
 227             event_irq = 1;
 228         }
 229         if (event_irq) {
 230             s->regs[IBEX_SPI_HOST_INTR_STATE] |= R_INTR_STATE_SPI_EVENT_MASK;
 231         }
 232         qemu_set_irq(s->event, event_irq);
 233     }
 234 }
 235
 236 static void ibex_spi_host_transfer(IbexSPIHostState *s)
 237 {
 238     uint32_t rx, tx, data;
 239     /* Get num of one byte transfers */
 240     uint8_t segment_len = FIELD_EX32(s->regs[IBEX_SPI_HOST_COMMAND],
 241                                      COMMAND,  LEN);
 242
 243     while (segment_len > 0) {
 244         if (fifo8_is_empty(&s->tx_fifo)) {
 245             /* Assert Stall */
 246             s->regs[IBEX_SPI_HOST_STATUS] |= R_STATUS_TXSTALL_MASK;
 247             break;
 248         } else if (fifo8_is_full(&s->rx_fifo)) {
 249             /* Assert Stall */
 250             s->regs[IBEX_SPI_HOST_STATUS] |= R_STATUS_RXSTALL_MASK;
 251             break;
 252         } else {
 253             tx = fifo8_pop(&s->tx_fifo);
 254         }
 255
 256         rx = ssi_transfer(s->ssi, tx);
 257
 258         trace_ibex_spi_host_transfer(tx, rx);
 259
 260         if (!fifo8_is_full(&s->rx_fifo)) {
 261             fifo8_push(&s->rx_fifo, rx);
 262         } else {
 263             /* Assert RXFULL */
 264             s->regs[IBEX_SPI_HOST_STATUS] |= R_STATUS_RXFULL_MASK;
 265         }
 266         --segment_len;
 267     }
 268
 269     data = s->regs[IBEX_SPI_HOST_STATUS];
 270     /* Assert Ready */
 271     data = FIELD_DP32(data, STATUS, READY, 1);
 272     /* Set RXQD */
 273     data = FIELD_DP32(data, STATUS, RXQD, div4_round_up(segment_len));
 274     /* Set TXQD */
 275     data = FIELD_DP32(data, STATUS, TXQD, fifo8_num_used(&s->tx_fifo) / 4);
 276     /* Clear TXFULL */
 277     data = FIELD_DP32(data, STATUS, TXFULL, 0);
 278     /* Reset RXEMPTY */
 279     data = FIELD_DP32(data, STATUS, RXEMPTY, 0);
 280     /* Update register status */
 281     s->regs[IBEX_SPI_HOST_STATUS] = data;
 282     /* Drop remaining bytes that exceed segment_len */
 283     ibex_spi_txfifo_reset(s);
 284
 285     ibex_spi_host_irq(s);
 286 }
 287
 288 static uint64_t ibex_spi_host_read(void *opaque, hwaddr addr,
 289                                      unsigned int size)
 290 {
 291     IbexSPIHostState *s = opaque;
 292     uint32_t rc = 0;
 293     uint8_t rx_byte = 0;
 294
 295     trace_ibex_spi_host_read(addr, size);
 296
 297     /* Match reg index */
 298     addr = addr >> 2;
 299     switch (addr) {
 300     /* Skipping any W/O registers */
 301     case IBEX_SPI_HOST_INTR_STATE...IBEX_SPI_HOST_INTR_ENABLE:
 302     case IBEX_SPI_HOST_CONTROL...IBEX_SPI_HOST_STATUS:
 303         rc = s->regs[addr];
 304         break;
 305     case IBEX_SPI_HOST_CSID:
 306         rc = s->regs[addr];
 307         break;
 308     case IBEX_SPI_HOST_CONFIGOPTS:
 309         rc = s->config_opts[s->regs[IBEX_SPI_HOST_CSID]];
 310         break;
 311     case IBEX_SPI_HOST_TXDATA:
 312         rc = s->regs[addr];
 313         break;
 314     case IBEX_SPI_HOST_RXDATA:
 315         /* Clear RXFULL */
 316         s->regs[IBEX_SPI_HOST_STATUS] &= ~R_STATUS_RXFULL_MASK;
 317
 318         for (int i = 0; i < 4; ++i) {
 319             if (fifo8_is_empty(&s->rx_fifo)) {
 320                 /* Assert RXEMPTY, no IRQ */
 321                 s->regs[IBEX_SPI_HOST_STATUS] |= R_STATUS_RXEMPTY_MASK;
 322                 s->regs[IBEX_SPI_HOST_ERROR_STATUS] |=
 323                                                 R_ERROR_STATUS_UNDERFLOW_MASK;
 324                 return rc;
 325             }
 326             rx_byte = fifo8_pop(&s->rx_fifo);
 327             rc |= rx_byte << (i * 8);
 328         }
 329         break;
 330     case IBEX_SPI_HOST_ERROR_ENABLE...IBEX_SPI_HOST_EVENT_ENABLE:
 331         rc = s->regs[addr];
 332         break;
 333     default:
 334         qemu_log_mask(LOG_GUEST_ERROR, "Bad offset 0x%" HWADDR_PRIx "\n",
 335                       addr << 2);
 336     }
 337     return rc;
 338 }
 339
 340
 341 static void ibex_spi_host_write(void *opaque, hwaddr addr,
 342                                 uint64_t val64, unsigned int size)
 343 {
 344     IbexSPIHostState *s = opaque;
 345     uint32_t val32 = val64;
 346     uint32_t shift_mask = 0xff, status = 0, data = 0;
 347     uint8_t txqd_len;
 348
 349     trace_ibex_spi_host_write(addr, size, val64);
 350
 351     /* Match reg index */
 352     addr = addr >> 2;
 353
 354     switch (addr) {
 355     /* Skipping any R/O registers */
 356     case IBEX_SPI_HOST_INTR_STATE:
 357         /* rw1c status register */
 358         if (FIELD_EX32(val32, INTR_STATE, ERROR)) {
 359             data = FIELD_DP32(data, INTR_STATE, ERROR, 0);
 360         }
 361         if (FIELD_EX32(val32, INTR_STATE, SPI_EVENT)) {
 362             data = FIELD_DP32(data, INTR_STATE, SPI_EVENT, 0);
 363         }
 364         s->regs[addr] = data;
 365         break;
 366     case IBEX_SPI_HOST_INTR_ENABLE:
 367         s->regs[addr] = val32;
 368         break;
 369     case IBEX_SPI_HOST_INTR_TEST:
 370         s->regs[addr] = val32;
 371         ibex_spi_host_irq(s);
 372         break;
 373     case IBEX_SPI_HOST_ALERT_TEST:
 374         s->regs[addr] = val32;
 375         qemu_log_mask(LOG_UNIMP,
 376                         "%s: SPI_ALERT_TEST is not supported\n", __func__);
 377         break;
 378     case IBEX_SPI_HOST_CONTROL:
 379         s->regs[addr] = val32;
 380
 381         if (val32 & R_CONTROL_SW_RST_MASK)  {
 382             ibex_spi_host_reset((DeviceState *)s);
 383             /* Clear active if any */
 384             s->regs[IBEX_SPI_HOST_STATUS] &=  ~R_STATUS_ACTIVE_MASK;
 385         }
 386
 387         if (val32 & R_CONTROL_OUTPUT_EN_MASK)  {
 388             qemu_log_mask(LOG_UNIMP,
 389                           "%s: CONTROL_OUTPUT_EN is not supported\n", __func__);
 390         }
 391         break;
 392     case IBEX_SPI_HOST_CONFIGOPTS:
 393         /* Update the respective config-opts register based on CSIDth index */
 394         s->config_opts[s->regs[IBEX_SPI_HOST_CSID]] = val32;
 395         qemu_log_mask(LOG_UNIMP,
 396                       "%s: CONFIGOPTS Hardware settings not supported\n",
 397                          __func__);
 398         break;
 399     case IBEX_SPI_HOST_CSID:
 400         if (val32 >= s->num_cs) {
 401             /* CSID exceeds max num_cs */
 402             s->regs[IBEX_SPI_HOST_ERROR_STATUS] |=
 403                                                 R_ERROR_STATUS_CSIDINVAL_MASK;
 404             ibex_spi_host_irq(s);
 405             return;
 406         }
 407         s->regs[addr] = val32;
 408         break;
 409     case IBEX_SPI_HOST_COMMAND:
 410         s->regs[addr] = val32;
 411
 412         /* STALL, IP not enabled */
 413         if (!(FIELD_EX32(s->regs[IBEX_SPI_HOST_CONTROL],
 414                          CONTROL, SPIEN))) {
 415             return;
 416         }
 417
 418         /* SPI not ready, IRQ Error */
 419         if (!(FIELD_EX32(s->regs[IBEX_SPI_HOST_STATUS],
 420                          STATUS, READY))) {
 421             s->regs[IBEX_SPI_HOST_ERROR_STATUS] |= R_ERROR_STATUS_CMDBUSY_MASK;
 422             ibex_spi_host_irq(s);
 423             return;
 424         }
 425
 426         /* Assert Not Ready */
 427         s->regs[IBEX_SPI_HOST_STATUS] &= ~R_STATUS_READY_MASK;
 428
 429         if (FIELD_EX32(val32, COMMAND, DIRECTION) != BIDIRECTIONAL_TRANSFER) {
 430             qemu_log_mask(LOG_UNIMP,
 431                           "%s: Rx Only/Tx Only are not supported\n", __func__);
 432         }
 433
 434         if (val32 & R_COMMAND_CSAAT_MASK)  {
 435             qemu_log_mask(LOG_UNIMP,
 436                           "%s: CSAAT is not supported\n", __func__);
 437         }
 438         if (val32 & R_COMMAND_SPEED_MASK)  {
 439             qemu_log_mask(LOG_UNIMP,
 440                           "%s: SPEED is not supported\n", __func__);
 441         }
 442
 443         /* Set Transfer Callback */
 444         timer_mod(s->fifo_trigger_handle,
 445                     qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
 446                     (TX_INTERRUPT_TRIGGER_DELAY_NS));
 447
 448         break;
 449     case IBEX_SPI_HOST_TXDATA:
 450         /*
 451          * This is a hardware `feature` where
 452          * the first word written to TXDATA after init is omitted entirely
 453          */
 454         if (s->init_status) {
 455             s->init_status = false;
 456             return;
 457         }
 458
 459         for (int i = 0; i < 4; ++i) {
 460             /* Attempting to write when TXFULL */
 461             if (fifo8_is_full(&s->tx_fifo)) {
 462                 /* Assert RXEMPTY, no IRQ */
 463                 s->regs[IBEX_SPI_HOST_STATUS] |= R_STATUS_TXFULL_MASK;
 464                 s->regs[IBEX_SPI_HOST_ERROR_STATUS] |=
 465                                                  R_ERROR_STATUS_OVERFLOW_MASK;
 466                 ibex_spi_host_irq(s);
 467                 return;
 468             }
 469             /* Byte ordering is set by the IP */
 470             status = s->regs[IBEX_SPI_HOST_STATUS];
 471             if (FIELD_EX32(status, STATUS, BYTEORDER) == 0) {
 472                 /* LE: LSB transmitted first (default for ibex processor) */
 473                 shift_mask = 0xff << (i * 8);
 474             } else {
 475                 /* BE: MSB transmitted first */
 476                 qemu_log_mask(LOG_UNIMP,
 477                              "%s: Big endian is not supported\n", __func__);
 478             }
 479
 480             fifo8_push(&s->tx_fifo, (val32 & shift_mask) >> (i * 8));
 481         }
 482         status = s->regs[IBEX_SPI_HOST_STATUS];
 483         /* Reset TXEMPTY */
 484         status = FIELD_DP32(status, STATUS, TXEMPTY, 0);
 485         /* Update TXQD */
 486         txqd_len = FIELD_EX32(status, STATUS, TXQD);
 487         /* Partial bytes (size < 4) are padded, in words. */
 488         txqd_len += 1;
 489         status = FIELD_DP32(status, STATUS, TXQD, txqd_len);
 490         /* Assert Ready */
 491         status = FIELD_DP32(status, STATUS, READY, 1);
 492         /* Update register status */
 493         s->regs[IBEX_SPI_HOST_STATUS] = status;
 494         break;
 495     case IBEX_SPI_HOST_ERROR_ENABLE:
 496         s->regs[addr] = val32;
 497
 498         if (val32 & R_ERROR_ENABLE_CMDINVAL_MASK)  {
 499             qemu_log_mask(LOG_UNIMP,
 500                           "%s: Segment Length is not supported\n", __func__);
 501         }
 502         break;
 503     case IBEX_SPI_HOST_ERROR_STATUS:
 504     /*
 505      *  Indicates any errors that have occurred.
 506      *  When an error occurs, the corresponding bit must be cleared
 507      *  here before issuing any further commands
 508      */
 509         status = s->regs[addr];
 510         /* rw1c status register */
 511         if (FIELD_EX32(val32, ERROR_STATUS, CMDBUSY)) {
 512             status = FIELD_DP32(status, ERROR_STATUS, CMDBUSY, 0);
 513         }
 514         if (FIELD_EX32(val32, ERROR_STATUS, OVERFLOW)) {
 515             status = FIELD_DP32(status, ERROR_STATUS, OVERFLOW, 0);
 516         }
 517         if (FIELD_EX32(val32, ERROR_STATUS, UNDERFLOW)) {
 518             status = FIELD_DP32(status, ERROR_STATUS, UNDERFLOW, 0);
 519         }
 520         if (FIELD_EX32(val32, ERROR_STATUS, CMDINVAL)) {
 521             status = FIELD_DP32(status, ERROR_STATUS, CMDINVAL, 0);
 522         }
 523         if (FIELD_EX32(val32, ERROR_STATUS, CSIDINVAL)) {
 524             status = FIELD_DP32(status, ERROR_STATUS, CSIDINVAL, 0);
 525         }
 526         if (FIELD_EX32(val32, ERROR_STATUS, ACCESSINVAL)) {
 527             status = FIELD_DP32(status, ERROR_STATUS, ACCESSINVAL, 0);
 528         }
 529         s->regs[addr] = status;
 530         break;
 531     case IBEX_SPI_HOST_EVENT_ENABLE:
 532     /* Controls which classes of SPI events raise an interrupt. */
 533         s->regs[addr] = val32;
 534
 535         if (val32 & R_EVENT_ENABLE_RXWM_MASK)  {
 536             qemu_log_mask(LOG_UNIMP,
 537                           "%s: RXWM is not supported\n", __func__);
 538         }
 539         if (val32 & R_EVENT_ENABLE_TXWM_MASK)  {
 540             qemu_log_mask(LOG_UNIMP,
 541                           "%s: TXWM is not supported\n", __func__);
 542         }
 543
 544         if (val32 & R_EVENT_ENABLE_IDLE_MASK)  {
 545             qemu_log_mask(LOG_UNIMP,
 546                           "%s: IDLE is not supported\n", __func__);
 547         }
 548         break;
 549     default:
 550         qemu_log_mask(LOG_GUEST_ERROR, "Bad offset 0x%" HWADDR_PRIx "\n",
 551                       addr << 2);
 552     }
 553 }
 554
 555 static const MemoryRegionOps ibex_spi_ops = {
 556     .read = ibex_spi_host_read,
 557     .write = ibex_spi_host_write,
 558     /* Ibex default LE */
 559     .endianness = DEVICE_LITTLE_ENDIAN,
 560 };
 561
 562 static Property ibex_spi_properties[] = {
 563     DEFINE_PROP_UINT32("num_cs", IbexSPIHostState, num_cs, 1),
 564     DEFINE_PROP_END_OF_LIST(),
 565 };
 566
 567 static const VMStateDescription vmstate_ibex = {
 568     .name = TYPE_IBEX_SPI_HOST,
 569     .version_id = 1,
 570     .minimum_version_id = 1,
 571     .fields = (VMStateField[]) {
 572         VMSTATE_UINT32_ARRAY(regs, IbexSPIHostState, IBEX_SPI_HOST_MAX_REGS),
 573         VMSTATE_VARRAY_UINT32(config_opts, IbexSPIHostState,
 574                               num_cs, 0, vmstate_info_uint32, uint32_t),
 575         VMSTATE_FIFO8(rx_fifo, IbexSPIHostState),
 576         VMSTATE_FIFO8(tx_fifo, IbexSPIHostState),
 577         VMSTATE_TIMER_PTR(fifo_trigger_handle, IbexSPIHostState),
 578         VMSTATE_BOOL(init_status, IbexSPIHostState),
 579         VMSTATE_END_OF_LIST()
 580     }
 581 };
 582
 583 static void fifo_trigger_update(void *opaque)
 584 {
 585     IbexSPIHostState *s = opaque;
 586     ibex_spi_host_transfer(s);
 587 }
 588
 589 static void ibex_spi_host_realize(DeviceState *dev, Error **errp)
 590 {
 591     IbexSPIHostState *s = IBEX_SPI_HOST(dev);
 592     int i;
 593
 594     s->ssi = ssi_create_bus(dev, "ssi");
 595     s->cs_lines = g_new0(qemu_irq, s->num_cs);
 596
 597     for (i = 0; i < s->num_cs; ++i) {
 598         sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->cs_lines[i]);
 599     }
 600
 601     /* Setup CONFIGOPTS Multi-register */
 602     s->config_opts = g_new0(uint32_t, s->num_cs);
 603
 604     /* Setup FIFO Interrupt Timer */
 605     s->fifo_trigger_handle = timer_new_ns(QEMU_CLOCK_VIRTUAL,
 606                                           fifo_trigger_update, s);
 607
 608     /* FIFO sizes as per OT Spec */
 609     fifo8_create(&s->tx_fifo, IBEX_SPI_HOST_TXFIFO_LEN);
 610     fifo8_create(&s->rx_fifo, IBEX_SPI_HOST_RXFIFO_LEN);
 611 }
 612
 613 static void ibex_spi_host_init(Object *obj)
 614 {
 615     IbexSPIHostState *s = IBEX_SPI_HOST(obj);
 616
 617     sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->host_err);
 618     sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->event);
 619
 620     memory_region_init_io(&s->mmio, obj, &ibex_spi_ops, s,
 621                           TYPE_IBEX_SPI_HOST, 0x1000);
 622     sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio);
 623 }
 624
 625 static void ibex_spi_host_class_init(ObjectClass *klass, void *data)
 626 {
 627     DeviceClass *dc = DEVICE_CLASS(klass);
 628     dc->realize = ibex_spi_host_realize;
 629     dc->reset = ibex_spi_host_reset;
 630     dc->vmsd = &vmstate_ibex;
 631     device_class_set_props(dc, ibex_spi_properties);
 632 }
 633
 634 static const TypeInfo ibex_spi_host_info = {
 635     .name          = TYPE_IBEX_SPI_HOST,
 636     .parent        = TYPE_SYS_BUS_DEVICE,
 637     .instance_size = sizeof(IbexSPIHostState),
 638     .instance_init = ibex_spi_host_init,
 639     .class_init    = ibex_spi_host_class_init,
 640 };
 641
 642 static void ibex_spi_host_register_types(void)
 643 {
 644     type_register_static(&ibex_spi_host_info);
 645 }
 646
 647 type_init(ibex_spi_host_register_types)