hw/net/allwinner_emac.c

   1 /*
   2  * Emulation of Allwinner EMAC Fast Ethernet controller and
   3  * Realtek RTL8201CP PHY
   4  *
   5  * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com>
   6  *
   7  * This model is based on reverse-engineering of Linux kernel driver.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU General Public License for more details.
  17  *
  18  */
  19 #include "qemu/osdep.h"
  20 #include "hw/sysbus.h"
  21 #include "net/net.h"
  22 #include "qemu/fifo8.h"
  23 #include "hw/net/allwinner_emac.h"
  24 #include "qemu/log.h"
  25 #include <zlib.h>
  26
  27 static uint8_t padding[60];
  28
  29 static void mii_set_link(RTL8201CPState *mii, bool link_ok)
  30 {
  31     if (link_ok) {
  32         mii->bmsr |= MII_BMSR_LINK_ST | MII_BMSR_AN_COMP;
  33         mii->anlpar |= MII_ANAR_TXFD | MII_ANAR_10FD | MII_ANAR_10 |
  34                        MII_ANAR_CSMACD;
  35     } else {
  36         mii->bmsr &= ~(MII_BMSR_LINK_ST | MII_BMSR_AN_COMP);
  37         mii->anlpar = MII_ANAR_TX;
  38     }
  39 }
  40
  41 static void mii_reset(RTL8201CPState *mii, bool link_ok)
  42 {
  43     mii->bmcr = MII_BMCR_FD | MII_BMCR_AUTOEN | MII_BMCR_SPEED;
  44     mii->bmsr = MII_BMSR_100TX_FD | MII_BMSR_100TX_HD | MII_BMSR_10T_FD |
  45                 MII_BMSR_10T_HD | MII_BMSR_MFPS | MII_BMSR_AUTONEG;
  46     mii->anar = MII_ANAR_TXFD | MII_ANAR_TX | MII_ANAR_10FD | MII_ANAR_10 |
  47                 MII_ANAR_CSMACD;
  48     mii->anlpar = MII_ANAR_TX;
  49
  50     mii_set_link(mii, link_ok);
  51 }
  52
  53 static uint16_t RTL8201CP_mdio_read(AwEmacState *s, uint8_t addr, uint8_t reg)
  54 {
  55     RTL8201CPState *mii = &s->mii;
  56     uint16_t ret = 0xffff;
  57
  58     if (addr == s->phy_addr) {
  59         switch (reg) {
  60         case MII_BMCR:
  61             return mii->bmcr;
  62         case MII_BMSR:
  63             return mii->bmsr;
  64         case MII_PHYID1:
  65             return RTL8201CP_PHYID1;
  66         case MII_PHYID2:
  67             return RTL8201CP_PHYID2;
  68         case MII_ANAR:
  69             return mii->anar;
  70         case MII_ANLPAR:
  71             return mii->anlpar;
  72         case MII_ANER:
  73         case MII_NSR:
  74         case MII_LBREMR:
  75         case MII_REC:
  76         case MII_SNRDR:
  77         case MII_TEST:
  78             qemu_log_mask(LOG_UNIMP,
  79                           "allwinner_emac: read from unimpl. mii reg 0x%x\n",
  80                           reg);
  81             return 0;
  82         default:
  83             qemu_log_mask(LOG_GUEST_ERROR,
  84                           "allwinner_emac: read from invalid mii reg 0x%x\n",
  85                           reg);
  86             return 0;
  87         }
  88     }
  89     return ret;
  90 }
  91
  92 static void RTL8201CP_mdio_write(AwEmacState *s, uint8_t addr, uint8_t reg,
  93                                  uint16_t value)
  94 {
  95     RTL8201CPState *mii = &s->mii;
  96     NetClientState *nc;
  97
  98     if (addr == s->phy_addr) {
  99         switch (reg) {
 100         case MII_BMCR:
 101             if (value & MII_BMCR_RESET) {
 102                 nc = qemu_get_queue(s->nic);
 103                 mii_reset(mii, !nc->link_down);
 104             } else {
 105                 mii->bmcr = value;
 106             }
 107             break;
 108         case MII_ANAR:
 109             mii->anar = value;
 110             break;
 111         case MII_BMSR:
 112         case MII_PHYID1:
 113         case MII_PHYID2:
 114         case MII_ANLPAR:
 115         case MII_ANER:
 116             qemu_log_mask(LOG_GUEST_ERROR,
 117                           "allwinner_emac: write to read-only mii reg 0x%x\n",
 118                           reg);
 119             break;
 120         case MII_NSR:
 121         case MII_LBREMR:
 122         case MII_REC:
 123         case MII_SNRDR:
 124         case MII_TEST:
 125             qemu_log_mask(LOG_UNIMP,
 126                           "allwinner_emac: write to unimpl. mii reg 0x%x\n",
 127                           reg);
 128             break;
 129         default:
 130             qemu_log_mask(LOG_GUEST_ERROR,
 131                           "allwinner_emac: write to invalid mii reg 0x%x\n",
 132                           reg);
 133         }
 134     }
 135 }
 136
 137 static void aw_emac_update_irq(AwEmacState *s)
 138 {
 139     qemu_set_irq(s->irq, (s->int_sta & s->int_ctl) != 0);
 140 }
 141
 142 static void aw_emac_tx_reset(AwEmacState *s, int chan)
 143 {
 144     fifo8_reset(&s->tx_fifo[chan]);
 145     s->tx_length[chan] = 0;
 146 }
 147
 148 static void aw_emac_rx_reset(AwEmacState *s)
 149 {
 150     fifo8_reset(&s->rx_fifo);
 151     s->rx_num_packets = 0;
 152     s->rx_packet_size = 0;
 153     s->rx_packet_pos = 0;
 154 }
 155
 156 static void fifo8_push_word(Fifo8 *fifo, uint32_t val)
 157 {
 158     fifo8_push(fifo, val);
 159     fifo8_push(fifo, val >> 8);
 160     fifo8_push(fifo, val >> 16);
 161     fifo8_push(fifo, val >> 24);
 162 }
 163
 164 static uint32_t fifo8_pop_word(Fifo8 *fifo)
 165 {
 166     uint32_t ret;
 167
 168     ret = fifo8_pop(fifo);
 169     ret |= fifo8_pop(fifo) << 8;
 170     ret |= fifo8_pop(fifo) << 16;
 171     ret |= fifo8_pop(fifo) << 24;
 172
 173     return ret;
 174 }
 175
 176 static int aw_emac_can_receive(NetClientState *nc)
 177 {
 178     AwEmacState *s = qemu_get_nic_opaque(nc);
 179
 180     /*
 181      * To avoid packet drops, allow reception only when there is space
 182      * for a full frame: 1522 + 8 (rx headers) + 2 (padding).
 183      */
 184     return (s->ctl & EMAC_CTL_RX_EN) && (fifo8_num_free(&s->rx_fifo) >= 1532);
 185 }
 186
 187 static ssize_t aw_emac_receive(NetClientState *nc, const uint8_t *buf,
 188                                size_t size)
 189 {
 190     AwEmacState *s = qemu_get_nic_opaque(nc);
 191     Fifo8 *fifo = &s->rx_fifo;
 192     size_t padded_size, total_size;
 193     uint32_t crc;
 194
 195     padded_size = size > 60 ? size : 60;
 196     total_size = QEMU_ALIGN_UP(RX_HDR_SIZE + padded_size + CRC_SIZE, 4);
 197
 198     if (!(s->ctl & EMAC_CTL_RX_EN) || (fifo8_num_free(fifo) < total_size)) {
 199         return -1;
 200     }
 201
 202     fifo8_push_word(fifo, EMAC_UNDOCUMENTED_MAGIC);
 203     fifo8_push_word(fifo, EMAC_RX_HEADER(padded_size + CRC_SIZE,
 204                                          EMAC_RX_IO_DATA_STATUS_OK));
 205     fifo8_push_all(fifo, buf, size);
 206     crc = crc32(~0, buf, size);
 207
 208     if (padded_size != size) {
 209         fifo8_push_all(fifo, padding, padded_size - size);
 210         crc = crc32(crc, padding, padded_size - size);
 211     }
 212
 213     fifo8_push_word(fifo, crc);
 214     fifo8_push_all(fifo, padding, QEMU_ALIGN_UP(padded_size, 4) - padded_size);
 215     s->rx_num_packets++;
 216
 217     s->int_sta |= EMAC_INT_RX;
 218     aw_emac_update_irq(s);
 219
 220     return size;
 221 }
 222
 223 static void aw_emac_reset(DeviceState *dev)
 224 {
 225     AwEmacState *s = AW_EMAC(dev);
 226     NetClientState *nc = qemu_get_queue(s->nic);
 227
 228     s->ctl = 0;
 229     s->tx_mode = 0;
 230     s->int_ctl = 0;
 231     s->int_sta = 0;
 232     s->tx_channel = 0;
 233     s->phy_target = 0;
 234
 235     aw_emac_tx_reset(s, 0);
 236     aw_emac_tx_reset(s, 1);
 237     aw_emac_rx_reset(s);
 238
 239     mii_reset(&s->mii, !nc->link_down);
 240 }
 241
 242 static uint64_t aw_emac_read(void *opaque, hwaddr offset, unsigned size)
 243 {
 244     AwEmacState *s = opaque;
 245     Fifo8 *fifo = &s->rx_fifo;
 246     NetClientState *nc;
 247     uint64_t ret;
 248
 249     switch (offset) {
 250     case EMAC_CTL_REG:
 251         return s->ctl;
 252     case EMAC_TX_MODE_REG:
 253         return s->tx_mode;
 254     case EMAC_TX_INS_REG:
 255         return s->tx_channel;
 256     case EMAC_RX_CTL_REG:
 257         return s->rx_ctl;
 258     case EMAC_RX_IO_DATA_REG:
 259         if (!s->rx_num_packets) {
 260             qemu_log_mask(LOG_GUEST_ERROR,
 261                           "Read IO data register when no packet available");
 262             return 0;
 263         }
 264
 265         ret = fifo8_pop_word(fifo);
 266
 267         switch (s->rx_packet_pos) {
 268         case 0:     /* Word is magic header */
 269             s->rx_packet_pos += 4;
 270             break;
 271         case 4:     /* Word is rx info header */
 272             s->rx_packet_pos += 4;
 273             s->rx_packet_size = QEMU_ALIGN_UP(extract32(ret, 0, 16), 4);
 274             break;
 275         default:    /* Word is packet data */
 276             s->rx_packet_pos += 4;
 277             s->rx_packet_size -= 4;
 278
 279             if (!s->rx_packet_size) {
 280                 s->rx_packet_pos = 0;
 281                 s->rx_num_packets--;
 282                 nc = qemu_get_queue(s->nic);
 283                 if (aw_emac_can_receive(nc)) {
 284                     qemu_flush_queued_packets(nc);
 285                 }
 286             }
 287         }
 288         return ret;
 289     case EMAC_RX_FBC_REG:
 290         return s->rx_num_packets;
 291     case EMAC_INT_CTL_REG:
 292         return s->int_ctl;
 293     case EMAC_INT_STA_REG:
 294         return s->int_sta;
 295     case EMAC_MAC_MRDD_REG:
 296         return RTL8201CP_mdio_read(s,
 297                                    extract32(s->phy_target, PHY_ADDR_SHIFT, 8),
 298                                    extract32(s->phy_target, PHY_REG_SHIFT, 8));
 299     default:
 300         qemu_log_mask(LOG_UNIMP,
 301                       "allwinner_emac: read access to unknown register 0x"
 302                       TARGET_FMT_plx "\n", offset);
 303         ret = 0;
 304     }
 305
 306     return ret;
 307 }
 308
 309 static void aw_emac_write(void *opaque, hwaddr offset, uint64_t value,
 310                           unsigned size)
 311 {
 312     AwEmacState *s = opaque;
 313     Fifo8 *fifo;
 314     NetClientState *nc = qemu_get_queue(s->nic);
 315     int chan;
 316
 317     switch (offset) {
 318     case EMAC_CTL_REG:
 319         if (value & EMAC_CTL_RESET) {
 320             aw_emac_reset(DEVICE(s));
 321             value &= ~EMAC_CTL_RESET;
 322         }
 323         s->ctl = value;
 324         if (aw_emac_can_receive(nc)) {
 325             qemu_flush_queued_packets(nc);
 326         }
 327         break;
 328     case EMAC_TX_MODE_REG:
 329         s->tx_mode = value;
 330         break;
 331     case EMAC_TX_CTL0_REG:
 332     case EMAC_TX_CTL1_REG:
 333         chan = (offset == EMAC_TX_CTL0_REG ? 0 : 1);
 334         if ((value & 1) && (s->ctl & EMAC_CTL_TX_EN)) {
 335             uint32_t len, ret;
 336             const uint8_t *data;
 337
 338             fifo = &s->tx_fifo[chan];
 339             len = s->tx_length[chan];
 340
 341             if (len > fifo8_num_used(fifo)) {
 342                 len = fifo8_num_used(fifo);
 343                 qemu_log_mask(LOG_GUEST_ERROR,
 344                               "allwinner_emac: TX length > fifo data length\n");
 345             }
 346             if (len > 0) {
 347                 data = fifo8_pop_buf(fifo, len, &ret);
 348                 qemu_send_packet(nc, data, ret);
 349                 aw_emac_tx_reset(s, chan);
 350                 /* Raise TX interrupt */
 351                 s->int_sta |= EMAC_INT_TX_CHAN(chan);
 352                 aw_emac_update_irq(s);
 353             }
 354         }
 355         break;
 356     case EMAC_TX_INS_REG:
 357         s->tx_channel = value < NUM_TX_FIFOS ? value : 0;
 358         break;
 359     case EMAC_TX_PL0_REG:
 360     case EMAC_TX_PL1_REG:
 361         chan = (offset == EMAC_TX_PL0_REG ? 0 : 1);
 362         if (value > TX_FIFO_SIZE) {
 363             qemu_log_mask(LOG_GUEST_ERROR,
 364                           "allwinner_emac: invalid TX frame length %d\n",
 365                           (int)value);
 366             value = TX_FIFO_SIZE;
 367         }
 368         s->tx_length[chan] = value;
 369         break;
 370     case EMAC_TX_IO_DATA_REG:
 371         fifo = &s->tx_fifo[s->tx_channel];
 372         if (fifo8_num_free(fifo) < 4) {
 373             qemu_log_mask(LOG_GUEST_ERROR,
 374                           "allwinner_emac: TX data overruns fifo\n");
 375             break;
 376         }
 377         fifo8_push_word(fifo, value);
 378         break;
 379     case EMAC_RX_CTL_REG:
 380         s->rx_ctl = value;
 381         break;
 382     case EMAC_RX_FBC_REG:
 383         if (value == 0) {
 384             aw_emac_rx_reset(s);
 385         }
 386         break;
 387     case EMAC_INT_CTL_REG:
 388         s->int_ctl = value;
 389         aw_emac_update_irq(s);
 390         break;
 391     case EMAC_INT_STA_REG:
 392         s->int_sta &= ~value;
 393         aw_emac_update_irq(s);
 394         break;
 395     case EMAC_MAC_MADR_REG:
 396         s->phy_target = value;
 397         break;
 398     case EMAC_MAC_MWTD_REG:
 399         RTL8201CP_mdio_write(s, extract32(s->phy_target, PHY_ADDR_SHIFT, 8),
 400                              extract32(s->phy_target, PHY_REG_SHIFT, 8), value);
 401         break;
 402     default:
 403         qemu_log_mask(LOG_UNIMP,
 404                       "allwinner_emac: write access to unknown register 0x"
 405                       TARGET_FMT_plx "\n", offset);
 406     }
 407 }
 408
 409 static void aw_emac_set_link(NetClientState *nc)
 410 {
 411     AwEmacState *s = qemu_get_nic_opaque(nc);
 412
 413     mii_set_link(&s->mii, !nc->link_down);
 414 }
 415
 416 static const MemoryRegionOps aw_emac_mem_ops = {
 417     .read = aw_emac_read,
 418     .write = aw_emac_write,
 419     .endianness = DEVICE_NATIVE_ENDIAN,
 420     .valid = {
 421         .min_access_size = 4,
 422         .max_access_size = 4,
 423     },
 424 };
 425
 426 static NetClientInfo net_aw_emac_info = {
 427     .type = NET_CLIENT_DRIVER_NIC,
 428     .size = sizeof(NICState),
 429     .can_receive = aw_emac_can_receive,
 430     .receive = aw_emac_receive,
 431     .link_status_changed = aw_emac_set_link,
 432 };
 433
 434 static void aw_emac_init(Object *obj)
 435 {
 436     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
 437     AwEmacState *s = AW_EMAC(obj);
 438
 439     memory_region_init_io(&s->iomem, OBJECT(s), &aw_emac_mem_ops, s,
 440                           "aw_emac", 0x1000);
 441     sysbus_init_mmio(sbd, &s->iomem);
 442     sysbus_init_irq(sbd, &s->irq);
 443 }
 444
 445 static void aw_emac_realize(DeviceState *dev, Error **errp)
 446 {
 447     AwEmacState *s = AW_EMAC(dev);
 448
 449     qemu_macaddr_default_if_unset(&s->conf.macaddr);
 450     s->nic = qemu_new_nic(&net_aw_emac_info, &s->conf,
 451                           object_get_typename(OBJECT(dev)), dev->id, s);
 452     qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
 453
 454     fifo8_create(&s->rx_fifo, RX_FIFO_SIZE);
 455     fifo8_create(&s->tx_fifo[0], TX_FIFO_SIZE);
 456     fifo8_create(&s->tx_fifo[1], TX_FIFO_SIZE);
 457 }
 458
 459 static Property aw_emac_properties[] = {
 460     DEFINE_NIC_PROPERTIES(AwEmacState, conf),
 461     DEFINE_PROP_UINT8("phy-addr", AwEmacState, phy_addr, 0),
 462     DEFINE_PROP_END_OF_LIST(),
 463 };
 464
 465 static const VMStateDescription vmstate_mii = {
 466     .name = "rtl8201cp",
 467     .version_id = 1,
 468     .minimum_version_id = 1,
 469     .fields = (VMStateField[]) {
 470         VMSTATE_UINT16(bmcr, RTL8201CPState),
 471         VMSTATE_UINT16(bmsr, RTL8201CPState),
 472         VMSTATE_UINT16(anar, RTL8201CPState),
 473         VMSTATE_UINT16(anlpar, RTL8201CPState),
 474         VMSTATE_END_OF_LIST()
 475     }
 476 };
 477
 478 static int aw_emac_post_load(void *opaque, int version_id)
 479 {
 480     AwEmacState *s = opaque;
 481
 482     aw_emac_set_link(qemu_get_queue(s->nic));
 483
 484     return 0;
 485 }
 486
 487 static const VMStateDescription vmstate_aw_emac = {
 488     .name = "allwinner_emac",
 489     .version_id = 1,
 490     .minimum_version_id = 1,
 491     .post_load = aw_emac_post_load,
 492     .fields = (VMStateField[]) {
 493         VMSTATE_STRUCT(mii, AwEmacState, 1, vmstate_mii, RTL8201CPState),
 494         VMSTATE_UINT32(ctl, AwEmacState),
 495         VMSTATE_UINT32(tx_mode, AwEmacState),
 496         VMSTATE_UINT32(rx_ctl, AwEmacState),
 497         VMSTATE_UINT32(int_ctl, AwEmacState),
 498         VMSTATE_UINT32(int_sta, AwEmacState),
 499         VMSTATE_UINT32(phy_target, AwEmacState),
 500         VMSTATE_FIFO8(rx_fifo, AwEmacState),
 501         VMSTATE_UINT32(rx_num_packets, AwEmacState),
 502         VMSTATE_UINT32(rx_packet_size, AwEmacState),
 503         VMSTATE_UINT32(rx_packet_pos, AwEmacState),
 504         VMSTATE_STRUCT_ARRAY(tx_fifo, AwEmacState, NUM_TX_FIFOS, 1,
 505                              vmstate_fifo8, Fifo8),
 506         VMSTATE_UINT32_ARRAY(tx_length, AwEmacState, NUM_TX_FIFOS),
 507         VMSTATE_UINT32(tx_channel, AwEmacState),
 508         VMSTATE_END_OF_LIST()
 509     }
 510 };
 511
 512 static void aw_emac_class_init(ObjectClass *klass, void *data)
 513 {
 514     DeviceClass *dc = DEVICE_CLASS(klass);
 515
 516     dc->realize = aw_emac_realize;
 517     dc->props = aw_emac_properties;
 518     dc->reset = aw_emac_reset;
 519     dc->vmsd = &vmstate_aw_emac;
 520 }
 521
 522 static const TypeInfo aw_emac_info = {
 523     .name           = TYPE_AW_EMAC,
 524     .parent         = TYPE_SYS_BUS_DEVICE,
 525     .instance_size  = sizeof(AwEmacState),
 526     .instance_init   = aw_emac_init,
 527     .class_init     = aw_emac_class_init,
 528 };
 529
 530 static void aw_emac_register_types(void)
 531 {
 532     type_register_static(&aw_emac_info);
 533 }
 534
 535 type_init(aw_emac_register_types)