qemu/hw/char/exynos4210_uart.c
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   1/*
   2 *  Exynos4210 UART Emulation
   3 *
   4 *  Copyright (C) 2011 Samsung Electronics Co Ltd.
   5 *    Maksim Kozlov, <m.kozlov@samsung.com>
   6 *
   7 *  This program is free software; you can redistribute it and/or modify it
   8 *  under the terms of the GNU General Public License as published by the
   9 *  Free Software Foundation; either version 2 of the License, or
  10 *  (at your option) any later version.
  11 *
  12 *  This program is distributed in the hope that it will be useful, but WITHOUT
  13 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 *  FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  15 *  for more details.
  16 *
  17 *  You should have received a copy of the GNU General Public License along
  18 *  with this program; if not, see <http://www.gnu.org/licenses/>.
  19 *
  20 */
  21
  22#include "qemu/osdep.h"
  23#include "hw/sysbus.h"
  24#include "migration/vmstate.h"
  25#include "qapi/error.h"
  26#include "qemu/error-report.h"
  27#include "qemu/module.h"
  28#include "qemu/timer.h"
  29#include "chardev/char-fe.h"
  30#include "chardev/char-serial.h"
  31
  32#include "hw/arm/exynos4210.h"
  33#include "hw/irq.h"
  34#include "hw/qdev-properties.h"
  35
  36#include "trace.h"
  37#include "qom/object.h"
  38
  39/*
  40 *  Offsets for UART registers relative to SFR base address
  41 *  for UARTn
  42 *
  43 */
  44#define ULCON      0x0000 /* Line Control             */
  45#define UCON       0x0004 /* Control                  */
  46#define UFCON      0x0008 /* FIFO Control             */
  47#define UMCON      0x000C /* Modem Control            */
  48#define UTRSTAT    0x0010 /* Tx/Rx Status             */
  49#define UERSTAT    0x0014 /* UART Error Status        */
  50#define UFSTAT     0x0018 /* FIFO Status              */
  51#define UMSTAT     0x001C /* Modem Status             */
  52#define UTXH       0x0020 /* Transmit Buffer          */
  53#define URXH       0x0024 /* Receive Buffer           */
  54#define UBRDIV     0x0028 /* Baud Rate Divisor        */
  55#define UFRACVAL   0x002C /* Divisor Fractional Value */
  56#define UINTP      0x0030 /* Interrupt Pending        */
  57#define UINTSP     0x0034 /* Interrupt Source Pending */
  58#define UINTM      0x0038 /* Interrupt Mask           */
  59
  60/*
  61 * for indexing register in the uint32_t array
  62 *
  63 * 'reg' - register offset (see offsets definitions above)
  64 *
  65 */
  66#define I_(reg) (reg / sizeof(uint32_t))
  67
  68typedef struct Exynos4210UartReg {
  69    const char         *name; /* the only reason is the debug output */
  70    hwaddr  offset;
  71    uint32_t            reset_value;
  72} Exynos4210UartReg;
  73
  74static const Exynos4210UartReg exynos4210_uart_regs[] = {
  75    {"ULCON",    ULCON,    0x00000000},
  76    {"UCON",     UCON,     0x00003000},
  77    {"UFCON",    UFCON,    0x00000000},
  78    {"UMCON",    UMCON,    0x00000000},
  79    {"UTRSTAT",  UTRSTAT,  0x00000006}, /* RO */
  80    {"UERSTAT",  UERSTAT,  0x00000000}, /* RO */
  81    {"UFSTAT",   UFSTAT,   0x00000000}, /* RO */
  82    {"UMSTAT",   UMSTAT,   0x00000000}, /* RO */
  83    {"UTXH",     UTXH,     0x5c5c5c5c}, /* WO, undefined reset value*/
  84    {"URXH",     URXH,     0x00000000}, /* RO */
  85    {"UBRDIV",   UBRDIV,   0x00000000},
  86    {"UFRACVAL", UFRACVAL, 0x00000000},
  87    {"UINTP",    UINTP,    0x00000000},
  88    {"UINTSP",   UINTSP,   0x00000000},
  89    {"UINTM",    UINTM,    0x00000000},
  90};
  91
  92#define EXYNOS4210_UART_REGS_MEM_SIZE    0x3C
  93
  94/* UART FIFO Control */
  95#define UFCON_FIFO_ENABLE                    0x1
  96#define UFCON_Rx_FIFO_RESET                  0x2
  97#define UFCON_Tx_FIFO_RESET                  0x4
  98#define UFCON_Tx_FIFO_TRIGGER_LEVEL_SHIFT    8
  99#define UFCON_Tx_FIFO_TRIGGER_LEVEL (7 << UFCON_Tx_FIFO_TRIGGER_LEVEL_SHIFT)
 100#define UFCON_Rx_FIFO_TRIGGER_LEVEL_SHIFT    4
 101#define UFCON_Rx_FIFO_TRIGGER_LEVEL (7 << UFCON_Rx_FIFO_TRIGGER_LEVEL_SHIFT)
 102
 103/* Uart FIFO Status */
 104#define UFSTAT_Rx_FIFO_COUNT        0xff
 105#define UFSTAT_Rx_FIFO_FULL         0x100
 106#define UFSTAT_Rx_FIFO_ERROR        0x200
 107#define UFSTAT_Tx_FIFO_COUNT_SHIFT  16
 108#define UFSTAT_Tx_FIFO_COUNT        (0xff << UFSTAT_Tx_FIFO_COUNT_SHIFT)
 109#define UFSTAT_Tx_FIFO_FULL_SHIFT   24
 110#define UFSTAT_Tx_FIFO_FULL         (1 << UFSTAT_Tx_FIFO_FULL_SHIFT)
 111
 112/* UART Interrupt Source Pending */
 113#define UINTSP_RXD      0x1 /* Receive interrupt  */
 114#define UINTSP_ERROR    0x2 /* Error interrupt    */
 115#define UINTSP_TXD      0x4 /* Transmit interrupt */
 116#define UINTSP_MODEM    0x8 /* Modem interrupt    */
 117
 118/* UART Line Control */
 119#define ULCON_IR_MODE_SHIFT   6
 120#define ULCON_PARITY_SHIFT    3
 121#define ULCON_STOP_BIT_SHIFT  1
 122
 123/* UART Tx/Rx Status */
 124#define UTRSTAT_Rx_TIMEOUT              0x8
 125#define UTRSTAT_TRANSMITTER_EMPTY       0x4
 126#define UTRSTAT_Tx_BUFFER_EMPTY         0x2
 127#define UTRSTAT_Rx_BUFFER_DATA_READY    0x1
 128
 129/* UART Error Status */
 130#define UERSTAT_OVERRUN  0x1
 131#define UERSTAT_PARITY   0x2
 132#define UERSTAT_FRAME    0x4
 133#define UERSTAT_BREAK    0x8
 134
 135typedef struct {
 136    uint8_t    *data;
 137    uint32_t    sp, rp; /* store and retrieve pointers */
 138    uint32_t    size;
 139} Exynos4210UartFIFO;
 140
 141#define TYPE_EXYNOS4210_UART "exynos4210.uart"
 142OBJECT_DECLARE_SIMPLE_TYPE(Exynos4210UartState, EXYNOS4210_UART)
 143
 144struct Exynos4210UartState {
 145    SysBusDevice parent_obj;
 146
 147    MemoryRegion iomem;
 148
 149    uint32_t             reg[EXYNOS4210_UART_REGS_MEM_SIZE / sizeof(uint32_t)];
 150    Exynos4210UartFIFO   rx;
 151    Exynos4210UartFIFO   tx;
 152
 153    QEMUTimer *fifo_timeout_timer;
 154    uint64_t wordtime;        /* word time in ns */
 155
 156    CharBackend       chr;
 157    qemu_irq          irq;
 158    qemu_irq          dmairq;
 159
 160    uint32_t channel;
 161
 162};
 163
 164
 165/* Used only for tracing */
 166static const char *exynos4210_uart_regname(hwaddr  offset)
 167{
 168
 169    int i;
 170
 171    for (i = 0; i < ARRAY_SIZE(exynos4210_uart_regs); i++) {
 172        if (offset == exynos4210_uart_regs[i].offset) {
 173            return exynos4210_uart_regs[i].name;
 174        }
 175    }
 176
 177    return NULL;
 178}
 179
 180
 181static void fifo_store(Exynos4210UartFIFO *q, uint8_t ch)
 182{
 183    q->data[q->sp] = ch;
 184    q->sp = (q->sp + 1) % q->size;
 185}
 186
 187static uint8_t fifo_retrieve(Exynos4210UartFIFO *q)
 188{
 189    uint8_t ret = q->data[q->rp];
 190    q->rp = (q->rp + 1) % q->size;
 191    return  ret;
 192}
 193
 194static int fifo_elements_number(const Exynos4210UartFIFO *q)
 195{
 196    if (q->sp < q->rp) {
 197        return q->size - q->rp + q->sp;
 198    }
 199
 200    return q->sp - q->rp;
 201}
 202
 203static int fifo_empty_elements_number(const Exynos4210UartFIFO *q)
 204{
 205    return q->size - fifo_elements_number(q);
 206}
 207
 208static void fifo_reset(Exynos4210UartFIFO *q)
 209{
 210    g_free(q->data);
 211    q->data = NULL;
 212
 213    q->data = (uint8_t *)g_malloc0(q->size);
 214
 215    q->sp = 0;
 216    q->rp = 0;
 217}
 218
 219static uint32_t exynos4210_uart_FIFO_trigger_level(uint32_t channel,
 220                                                   uint32_t reg)
 221{
 222    uint32_t level;
 223
 224    switch (channel) {
 225    case 0:
 226        level = reg * 32;
 227        break;
 228    case 1:
 229    case 4:
 230        level = reg * 8;
 231        break;
 232    case 2:
 233    case 3:
 234        level = reg * 2;
 235        break;
 236    default:
 237        level = 0;
 238        trace_exynos_uart_channel_error(channel);
 239        break;
 240    }
 241    return level;
 242}
 243
 244static uint32_t
 245exynos4210_uart_Tx_FIFO_trigger_level(const Exynos4210UartState *s)
 246{
 247    uint32_t reg;
 248
 249    reg = (s->reg[I_(UFCON)] & UFCON_Tx_FIFO_TRIGGER_LEVEL) >>
 250            UFCON_Tx_FIFO_TRIGGER_LEVEL_SHIFT;
 251
 252    return exynos4210_uart_FIFO_trigger_level(s->channel, reg);
 253}
 254
 255static uint32_t
 256exynos4210_uart_Rx_FIFO_trigger_level(const Exynos4210UartState *s)
 257{
 258    uint32_t reg;
 259
 260    reg = ((s->reg[I_(UFCON)] & UFCON_Rx_FIFO_TRIGGER_LEVEL) >>
 261            UFCON_Rx_FIFO_TRIGGER_LEVEL_SHIFT) + 1;
 262
 263    return exynos4210_uart_FIFO_trigger_level(s->channel, reg);
 264}
 265
 266/*
 267 * Update Rx DMA busy signal if Rx DMA is enabled. For simplicity,
 268 * mark DMA as busy if DMA is enabled and the receive buffer is empty.
 269 */
 270static void exynos4210_uart_update_dmabusy(Exynos4210UartState *s)
 271{
 272    bool rx_dma_enabled = (s->reg[I_(UCON)] & 0x03) == 0x02;
 273    uint32_t count = fifo_elements_number(&s->rx);
 274
 275    if (rx_dma_enabled && !count) {
 276        qemu_irq_raise(s->dmairq);
 277        trace_exynos_uart_dmabusy(s->channel);
 278    } else {
 279        qemu_irq_lower(s->dmairq);
 280        trace_exynos_uart_dmaready(s->channel);
 281    }
 282}
 283
 284static void exynos4210_uart_update_irq(Exynos4210UartState *s)
 285{
 286    /*
 287     * The Tx interrupt is always requested if the number of data in the
 288     * transmit FIFO is smaller than the trigger level.
 289     */
 290    if (s->reg[I_(UFCON)] & UFCON_FIFO_ENABLE) {
 291        uint32_t count = (s->reg[I_(UFSTAT)] & UFSTAT_Tx_FIFO_COUNT) >>
 292                UFSTAT_Tx_FIFO_COUNT_SHIFT;
 293
 294        if (count <= exynos4210_uart_Tx_FIFO_trigger_level(s)) {
 295            s->reg[I_(UINTSP)] |= UINTSP_TXD;
 296        }
 297
 298        /*
 299         * Rx interrupt if trigger level is reached or if rx timeout
 300         * interrupt is disabled and there is data in the receive buffer
 301         */
 302        count = fifo_elements_number(&s->rx);
 303        if ((count && !(s->reg[I_(UCON)] & 0x80)) ||
 304            count >= exynos4210_uart_Rx_FIFO_trigger_level(s)) {
 305            exynos4210_uart_update_dmabusy(s);
 306            s->reg[I_(UINTSP)] |= UINTSP_RXD;
 307            timer_del(s->fifo_timeout_timer);
 308        }
 309    } else if (s->reg[I_(UTRSTAT)] & UTRSTAT_Rx_BUFFER_DATA_READY) {
 310        exynos4210_uart_update_dmabusy(s);
 311        s->reg[I_(UINTSP)] |= UINTSP_RXD;
 312    }
 313
 314    s->reg[I_(UINTP)] = s->reg[I_(UINTSP)] & ~s->reg[I_(UINTM)];
 315
 316    if (s->reg[I_(UINTP)]) {
 317        qemu_irq_raise(s->irq);
 318        trace_exynos_uart_irq_raised(s->channel, s->reg[I_(UINTP)]);
 319    } else {
 320        qemu_irq_lower(s->irq);
 321        trace_exynos_uart_irq_lowered(s->channel);
 322    }
 323}
 324
 325static void exynos4210_uart_timeout_int(void *opaque)
 326{
 327    Exynos4210UartState *s = opaque;
 328
 329    trace_exynos_uart_rx_timeout(s->channel, s->reg[I_(UTRSTAT)],
 330                                 s->reg[I_(UINTSP)]);
 331
 332    if ((s->reg[I_(UTRSTAT)] & UTRSTAT_Rx_BUFFER_DATA_READY) ||
 333        (s->reg[I_(UCON)] & (1 << 11))) {
 334        s->reg[I_(UINTSP)] |= UINTSP_RXD;
 335        s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_TIMEOUT;
 336        exynos4210_uart_update_dmabusy(s);
 337        exynos4210_uart_update_irq(s);
 338    }
 339}
 340
 341static void exynos4210_uart_update_parameters(Exynos4210UartState *s)
 342{
 343    int speed, parity, data_bits, stop_bits;
 344    QEMUSerialSetParams ssp;
 345    uint64_t uclk_rate;
 346
 347    if (s->reg[I_(UBRDIV)] == 0) {
 348        return;
 349    }
 350
 351    if (s->reg[I_(ULCON)] & 0x20) {
 352        if (s->reg[I_(ULCON)] & 0x28) {
 353            parity = 'E';
 354        } else {
 355            parity = 'O';
 356        }
 357    } else {
 358        parity = 'N';
 359    }
 360
 361    if (s->reg[I_(ULCON)] & 0x4) {
 362        stop_bits = 2;
 363    } else {
 364        stop_bits = 1;
 365    }
 366
 367    data_bits = (s->reg[I_(ULCON)] & 0x3) + 5;
 368
 369    uclk_rate = 24000000;
 370
 371    speed = uclk_rate / ((16 * (s->reg[I_(UBRDIV)]) & 0xffff) +
 372            (s->reg[I_(UFRACVAL)] & 0x7) + 16);
 373
 374    ssp.speed     = speed;
 375    ssp.parity    = parity;
 376    ssp.data_bits = data_bits;
 377    ssp.stop_bits = stop_bits;
 378
 379    s->wordtime = NANOSECONDS_PER_SECOND * (data_bits + stop_bits + 1) / speed;
 380
 381    qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_SERIAL_SET_PARAMS, &ssp);
 382
 383    trace_exynos_uart_update_params(
 384                s->channel, speed, parity, data_bits, stop_bits, s->wordtime);
 385}
 386
 387static void exynos4210_uart_rx_timeout_set(Exynos4210UartState *s)
 388{
 389    if (s->reg[I_(UCON)] & 0x80) {
 390        uint32_t timeout = ((s->reg[I_(UCON)] >> 12) & 0x0f) * s->wordtime;
 391
 392        timer_mod(s->fifo_timeout_timer,
 393                  qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + timeout);
 394    } else {
 395        timer_del(s->fifo_timeout_timer);
 396    }
 397}
 398
 399static void exynos4210_uart_write(void *opaque, hwaddr offset,
 400                               uint64_t val, unsigned size)
 401{
 402    Exynos4210UartState *s = (Exynos4210UartState *)opaque;
 403    uint8_t ch;
 404
 405    trace_exynos_uart_write(s->channel, offset,
 406                            exynos4210_uart_regname(offset), val);
 407
 408    switch (offset) {
 409    case ULCON:
 410    case UBRDIV:
 411    case UFRACVAL:
 412        s->reg[I_(offset)] = val;
 413        exynos4210_uart_update_parameters(s);
 414        break;
 415    case UFCON:
 416        s->reg[I_(UFCON)] = val;
 417        if (val & UFCON_Rx_FIFO_RESET) {
 418            fifo_reset(&s->rx);
 419            s->reg[I_(UFCON)] &= ~UFCON_Rx_FIFO_RESET;
 420            trace_exynos_uart_rx_fifo_reset(s->channel);
 421        }
 422        if (val & UFCON_Tx_FIFO_RESET) {
 423            fifo_reset(&s->tx);
 424            s->reg[I_(UFCON)] &= ~UFCON_Tx_FIFO_RESET;
 425            trace_exynos_uart_tx_fifo_reset(s->channel);
 426        }
 427        break;
 428
 429    case UTXH:
 430        if (qemu_chr_fe_backend_connected(&s->chr)) {
 431            s->reg[I_(UTRSTAT)] &= ~(UTRSTAT_TRANSMITTER_EMPTY |
 432                    UTRSTAT_Tx_BUFFER_EMPTY);
 433            ch = (uint8_t)val;
 434            /* XXX this blocks entire thread. Rewrite to use
 435             * qemu_chr_fe_write and background I/O callbacks */
 436            qemu_chr_fe_write_all(&s->chr, &ch, 1);
 437            trace_exynos_uart_tx(s->channel, ch);
 438            s->reg[I_(UTRSTAT)] |= UTRSTAT_TRANSMITTER_EMPTY |
 439                    UTRSTAT_Tx_BUFFER_EMPTY;
 440            s->reg[I_(UINTSP)]  |= UINTSP_TXD;
 441            exynos4210_uart_update_irq(s);
 442        }
 443        break;
 444
 445    case UINTP:
 446        s->reg[I_(UINTP)] &= ~val;
 447        s->reg[I_(UINTSP)] &= ~val;
 448        trace_exynos_uart_intclr(s->channel, s->reg[I_(UINTP)]);
 449        exynos4210_uart_update_irq(s);
 450        break;
 451    case UTRSTAT:
 452        if (val & UTRSTAT_Rx_TIMEOUT) {
 453            s->reg[I_(UTRSTAT)] &= ~UTRSTAT_Rx_TIMEOUT;
 454        }
 455        break;
 456    case UERSTAT:
 457    case UFSTAT:
 458    case UMSTAT:
 459    case URXH:
 460        trace_exynos_uart_ro_write(
 461                    s->channel, exynos4210_uart_regname(offset), offset);
 462        break;
 463    case UINTSP:
 464        s->reg[I_(UINTSP)]  &= ~val;
 465        break;
 466    case UINTM:
 467        s->reg[I_(UINTM)] = val;
 468        exynos4210_uart_update_irq(s);
 469        break;
 470    case UCON:
 471    case UMCON:
 472    default:
 473        s->reg[I_(offset)] = val;
 474        break;
 475    }
 476}
 477
 478static uint64_t exynos4210_uart_read(void *opaque, hwaddr offset,
 479                                  unsigned size)
 480{
 481    Exynos4210UartState *s = (Exynos4210UartState *)opaque;
 482    uint32_t res;
 483
 484    switch (offset) {
 485    case UERSTAT: /* Read Only */
 486        res = s->reg[I_(UERSTAT)];
 487        s->reg[I_(UERSTAT)] = 0;
 488        trace_exynos_uart_read(s->channel, offset,
 489                               exynos4210_uart_regname(offset), res);
 490        return res;
 491    case UFSTAT: /* Read Only */
 492        s->reg[I_(UFSTAT)] = fifo_elements_number(&s->rx) & 0xff;
 493        if (fifo_empty_elements_number(&s->rx) == 0) {
 494            s->reg[I_(UFSTAT)] |= UFSTAT_Rx_FIFO_FULL;
 495            s->reg[I_(UFSTAT)] &= ~0xff;
 496        }
 497        trace_exynos_uart_read(s->channel, offset,
 498                               exynos4210_uart_regname(offset),
 499                               s->reg[I_(UFSTAT)]);
 500        return s->reg[I_(UFSTAT)];
 501    case URXH:
 502        if (s->reg[I_(UFCON)] & UFCON_FIFO_ENABLE) {
 503            if (fifo_elements_number(&s->rx)) {
 504                res = fifo_retrieve(&s->rx);
 505                trace_exynos_uart_rx(s->channel, res);
 506                if (!fifo_elements_number(&s->rx)) {
 507                    s->reg[I_(UTRSTAT)] &= ~UTRSTAT_Rx_BUFFER_DATA_READY;
 508                } else {
 509                    s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_BUFFER_DATA_READY;
 510                }
 511            } else {
 512                trace_exynos_uart_rx_error(s->channel);
 513                s->reg[I_(UINTSP)] |= UINTSP_ERROR;
 514                exynos4210_uart_update_irq(s);
 515                res = 0;
 516            }
 517        } else {
 518            s->reg[I_(UTRSTAT)] &= ~UTRSTAT_Rx_BUFFER_DATA_READY;
 519            res = s->reg[I_(URXH)];
 520        }
 521        exynos4210_uart_update_dmabusy(s);
 522        trace_exynos_uart_read(s->channel, offset,
 523                               exynos4210_uart_regname(offset), res);
 524        return res;
 525    case UTXH:
 526        trace_exynos_uart_wo_read(s->channel, exynos4210_uart_regname(offset),
 527                                  offset);
 528        break;
 529    default:
 530        trace_exynos_uart_read(s->channel, offset,
 531                               exynos4210_uart_regname(offset),
 532                               s->reg[I_(offset)]);
 533        return s->reg[I_(offset)];
 534    }
 535
 536    trace_exynos_uart_read(s->channel, offset, exynos4210_uart_regname(offset),
 537                           0);
 538    return 0;
 539}
 540
 541static const MemoryRegionOps exynos4210_uart_ops = {
 542    .read = exynos4210_uart_read,
 543    .write = exynos4210_uart_write,
 544    .endianness = DEVICE_NATIVE_ENDIAN,
 545    .valid = {
 546        .max_access_size = 4,
 547        .unaligned = false
 548    },
 549};
 550
 551static int exynos4210_uart_can_receive(void *opaque)
 552{
 553    Exynos4210UartState *s = (Exynos4210UartState *)opaque;
 554
 555    return fifo_empty_elements_number(&s->rx);
 556}
 557
 558static void exynos4210_uart_receive(void *opaque, const uint8_t *buf, int size)
 559{
 560    Exynos4210UartState *s = (Exynos4210UartState *)opaque;
 561    int i;
 562
 563    if (s->reg[I_(UFCON)] & UFCON_FIFO_ENABLE) {
 564        if (fifo_empty_elements_number(&s->rx) < size) {
 565            size = fifo_empty_elements_number(&s->rx);
 566            s->reg[I_(UINTSP)] |= UINTSP_ERROR;
 567        }
 568        for (i = 0; i < size; i++) {
 569            fifo_store(&s->rx, buf[i]);
 570        }
 571        exynos4210_uart_rx_timeout_set(s);
 572    } else {
 573        s->reg[I_(URXH)] = buf[0];
 574    }
 575    s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_BUFFER_DATA_READY;
 576
 577    exynos4210_uart_update_irq(s);
 578}
 579
 580
 581static void exynos4210_uart_event(void *opaque, QEMUChrEvent event)
 582{
 583    Exynos4210UartState *s = (Exynos4210UartState *)opaque;
 584
 585    if (event == CHR_EVENT_BREAK) {
 586        /* When the RxDn is held in logic 0, then a null byte is pushed into the
 587         * fifo */
 588        fifo_store(&s->rx, '\0');
 589        s->reg[I_(UERSTAT)] |= UERSTAT_BREAK;
 590        exynos4210_uart_update_irq(s);
 591    }
 592}
 593
 594
 595static void exynos4210_uart_reset(DeviceState *dev)
 596{
 597    Exynos4210UartState *s = EXYNOS4210_UART(dev);
 598    int i;
 599
 600    for (i = 0; i < ARRAY_SIZE(exynos4210_uart_regs); i++) {
 601        s->reg[I_(exynos4210_uart_regs[i].offset)] =
 602                exynos4210_uart_regs[i].reset_value;
 603    }
 604
 605    fifo_reset(&s->rx);
 606    fifo_reset(&s->tx);
 607
 608    trace_exynos_uart_rxsize(s->channel, s->rx.size);
 609}
 610
 611static int exynos4210_uart_post_load(void *opaque, int version_id)
 612{
 613    Exynos4210UartState *s = (Exynos4210UartState *)opaque;
 614
 615    exynos4210_uart_update_parameters(s);
 616    exynos4210_uart_rx_timeout_set(s);
 617
 618    return 0;
 619}
 620
 621static const VMStateDescription vmstate_exynos4210_uart_fifo = {
 622    .name = "exynos4210.uart.fifo",
 623    .version_id = 1,
 624    .minimum_version_id = 1,
 625    .post_load = exynos4210_uart_post_load,
 626    .fields = (VMStateField[]) {
 627        VMSTATE_UINT32(sp, Exynos4210UartFIFO),
 628        VMSTATE_UINT32(rp, Exynos4210UartFIFO),
 629        VMSTATE_VBUFFER_UINT32(data, Exynos4210UartFIFO, 1, NULL, size),
 630        VMSTATE_END_OF_LIST()
 631    }
 632};
 633
 634static const VMStateDescription vmstate_exynos4210_uart = {
 635    .name = "exynos4210.uart",
 636    .version_id = 1,
 637    .minimum_version_id = 1,
 638    .fields = (VMStateField[]) {
 639        VMSTATE_STRUCT(rx, Exynos4210UartState, 1,
 640                       vmstate_exynos4210_uart_fifo, Exynos4210UartFIFO),
 641        VMSTATE_UINT32_ARRAY(reg, Exynos4210UartState,
 642                             EXYNOS4210_UART_REGS_MEM_SIZE / sizeof(uint32_t)),
 643        VMSTATE_END_OF_LIST()
 644    }
 645};
 646
 647DeviceState *exynos4210_uart_create(hwaddr addr,
 648                                    int fifo_size,
 649                                    int channel,
 650                                    Chardev *chr,
 651                                    qemu_irq irq)
 652{
 653    DeviceState  *dev;
 654    SysBusDevice *bus;
 655
 656    dev = qdev_new(TYPE_EXYNOS4210_UART);
 657
 658    qdev_prop_set_chr(dev, "chardev", chr);
 659    qdev_prop_set_uint32(dev, "channel", channel);
 660    qdev_prop_set_uint32(dev, "rx-size", fifo_size);
 661    qdev_prop_set_uint32(dev, "tx-size", fifo_size);
 662
 663    bus = SYS_BUS_DEVICE(dev);
 664    sysbus_realize_and_unref(bus, &error_fatal);
 665    if (addr != (hwaddr)-1) {
 666        sysbus_mmio_map(bus, 0, addr);
 667    }
 668    sysbus_connect_irq(bus, 0, irq);
 669
 670    return dev;
 671}
 672
 673static void exynos4210_uart_init(Object *obj)
 674{
 675    SysBusDevice *dev = SYS_BUS_DEVICE(obj);
 676    Exynos4210UartState *s = EXYNOS4210_UART(dev);
 677
 678    s->wordtime = NANOSECONDS_PER_SECOND * 10 / 9600;
 679
 680    /* memory mapping */
 681    memory_region_init_io(&s->iomem, obj, &exynos4210_uart_ops, s,
 682                          "exynos4210.uart", EXYNOS4210_UART_REGS_MEM_SIZE);
 683    sysbus_init_mmio(dev, &s->iomem);
 684
 685    sysbus_init_irq(dev, &s->irq);
 686    sysbus_init_irq(dev, &s->dmairq);
 687}
 688
 689static void exynos4210_uart_realize(DeviceState *dev, Error **errp)
 690{
 691    Exynos4210UartState *s = EXYNOS4210_UART(dev);
 692
 693    s->fifo_timeout_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
 694                                         exynos4210_uart_timeout_int, s);
 695
 696    qemu_chr_fe_set_handlers(&s->chr, exynos4210_uart_can_receive,
 697                             exynos4210_uart_receive, exynos4210_uart_event,
 698                             NULL, s, NULL, true);
 699}
 700
 701static Property exynos4210_uart_properties[] = {
 702    DEFINE_PROP_CHR("chardev", Exynos4210UartState, chr),
 703    DEFINE_PROP_UINT32("channel", Exynos4210UartState, channel, 0),
 704    DEFINE_PROP_UINT32("rx-size", Exynos4210UartState, rx.size, 16),
 705    DEFINE_PROP_UINT32("tx-size", Exynos4210UartState, tx.size, 16),
 706    DEFINE_PROP_END_OF_LIST(),
 707};
 708
 709static void exynos4210_uart_class_init(ObjectClass *klass, void *data)
 710{
 711    DeviceClass *dc = DEVICE_CLASS(klass);
 712
 713    dc->realize = exynos4210_uart_realize;
 714    dc->reset = exynos4210_uart_reset;
 715    device_class_set_props(dc, exynos4210_uart_properties);
 716    dc->vmsd = &vmstate_exynos4210_uart;
 717}
 718
 719static const TypeInfo exynos4210_uart_info = {
 720    .name          = TYPE_EXYNOS4210_UART,
 721    .parent        = TYPE_SYS_BUS_DEVICE,
 722    .instance_size = sizeof(Exynos4210UartState),
 723    .instance_init = exynos4210_uart_init,
 724    .class_init    = exynos4210_uart_class_init,
 725};
 726
 727static void exynos4210_uart_register(void)
 728{
 729    type_register_static(&exynos4210_uart_info);
 730}
 731
 732type_init(exynos4210_uart_register)
 733