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