hw/mcf_fec.c

   1 /*
   2  * ColdFire Fast Ethernet Controller emulation.
   3  *
   4  * Copyright (c) 2007 CodeSourcery.
   5  *
   6  * This code is licensed under the GPL
   7  */
   8 #include "hw.h"
   9 #include "net/net.h"
  10 #include "mcf.h"
  11 /* For crc32 */
  12 #include <zlib.h>
  13 #include "exec/address-spaces.h"
  14
  15 //#define DEBUG_FEC 1
  16
  17 #ifdef DEBUG_FEC
  18 #define DPRINTF(fmt, ...) \
  19 do { printf("mcf_fec: " fmt , ## __VA_ARGS__); } while (0)
  20 #else
  21 #define DPRINTF(fmt, ...) do {} while(0)
  22 #endif
  23
  24 #define FEC_MAX_FRAME_SIZE 2032
  25
  26 typedef struct {
  27     MemoryRegion *sysmem;
  28     MemoryRegion iomem;
  29     qemu_irq *irq;
  30     NICState *nic;
  31     NICConf conf;
  32     uint32_t irq_state;
  33     uint32_t eir;
  34     uint32_t eimr;
  35     int rx_enabled;
  36     uint32_t rx_descriptor;
  37     uint32_t tx_descriptor;
  38     uint32_t ecr;
  39     uint32_t mmfr;
  40     uint32_t mscr;
  41     uint32_t rcr;
  42     uint32_t tcr;
  43     uint32_t tfwr;
  44     uint32_t rfsr;
  45     uint32_t erdsr;
  46     uint32_t etdsr;
  47     uint32_t emrbr;
  48 } mcf_fec_state;
  49
  50 #define FEC_INT_HB   0x80000000
  51 #define FEC_INT_BABR 0x40000000
  52 #define FEC_INT_BABT 0x20000000
  53 #define FEC_INT_GRA  0x10000000
  54 #define FEC_INT_TXF  0x08000000
  55 #define FEC_INT_TXB  0x04000000
  56 #define FEC_INT_RXF  0x02000000
  57 #define FEC_INT_RXB  0x01000000
  58 #define FEC_INT_MII  0x00800000
  59 #define FEC_INT_EB   0x00400000
  60 #define FEC_INT_LC   0x00200000
  61 #define FEC_INT_RL   0x00100000
  62 #define FEC_INT_UN   0x00080000
  63
  64 #define FEC_EN      2
  65 #define FEC_RESET   1
  66
  67 /* Map interrupt flags onto IRQ lines.  */
  68 #define FEC_NUM_IRQ 13
  69 static const uint32_t mcf_fec_irq_map[FEC_NUM_IRQ] = {
  70     FEC_INT_TXF,
  71     FEC_INT_TXB,
  72     FEC_INT_UN,
  73     FEC_INT_RL,
  74     FEC_INT_RXF,
  75     FEC_INT_RXB,
  76     FEC_INT_MII,
  77     FEC_INT_LC,
  78     FEC_INT_HB,
  79     FEC_INT_GRA,
  80     FEC_INT_EB,
  81     FEC_INT_BABT,
  82     FEC_INT_BABR
  83 };
  84
  85 /* Buffer Descriptor.  */
  86 typedef struct {
  87     uint16_t flags;
  88     uint16_t length;
  89     uint32_t data;
  90 } mcf_fec_bd;
  91
  92 #define FEC_BD_R    0x8000
  93 #define FEC_BD_E    0x8000
  94 #define FEC_BD_O1   0x4000
  95 #define FEC_BD_W    0x2000
  96 #define FEC_BD_O2   0x1000
  97 #define FEC_BD_L    0x0800
  98 #define FEC_BD_TC   0x0400
  99 #define FEC_BD_ABC  0x0200
 100 #define FEC_BD_M    0x0100
 101 #define FEC_BD_BC   0x0080
 102 #define FEC_BD_MC   0x0040
 103 #define FEC_BD_LG   0x0020
 104 #define FEC_BD_NO   0x0010
 105 #define FEC_BD_CR   0x0004
 106 #define FEC_BD_OV   0x0002
 107 #define FEC_BD_TR   0x0001
 108
 109 static void mcf_fec_read_bd(mcf_fec_bd *bd, uint32_t addr)
 110 {
 111     cpu_physical_memory_read(addr, (uint8_t *)bd, sizeof(*bd));
 112     be16_to_cpus(&bd->flags);
 113     be16_to_cpus(&bd->length);
 114     be32_to_cpus(&bd->data);
 115 }
 116
 117 static void mcf_fec_write_bd(mcf_fec_bd *bd, uint32_t addr)
 118 {
 119     mcf_fec_bd tmp;
 120     tmp.flags = cpu_to_be16(bd->flags);
 121     tmp.length = cpu_to_be16(bd->length);
 122     tmp.data = cpu_to_be32(bd->data);
 123     cpu_physical_memory_write(addr, (uint8_t *)&tmp, sizeof(tmp));
 124 }
 125
 126 static void mcf_fec_update(mcf_fec_state *s)
 127 {
 128     uint32_t active;
 129     uint32_t changed;
 130     uint32_t mask;
 131     int i;
 132
 133     active = s->eir & s->eimr;
 134     changed = active ^s->irq_state;
 135     for (i = 0; i < FEC_NUM_IRQ; i++) {
 136         mask = mcf_fec_irq_map[i];
 137         if (changed & mask) {
 138             DPRINTF("IRQ %d = %d\n", i, (active & mask) != 0);
 139             qemu_set_irq(s->irq[i], (active & mask) != 0);
 140         }
 141     }
 142     s->irq_state = active;
 143 }
 144
 145 static void mcf_fec_do_tx(mcf_fec_state *s)
 146 {
 147     uint32_t addr;
 148     mcf_fec_bd bd;
 149     int frame_size;
 150     int len;
 151     uint8_t frame[FEC_MAX_FRAME_SIZE];
 152     uint8_t *ptr;
 153
 154     DPRINTF("do_tx\n");
 155     ptr = frame;
 156     frame_size = 0;
 157     addr = s->tx_descriptor;
 158     while (1) {
 159         mcf_fec_read_bd(&bd, addr);
 160         DPRINTF("tx_bd %x flags %04x len %d data %08x\n",
 161                 addr, bd.flags, bd.length, bd.data);
 162         if ((bd.flags & FEC_BD_R) == 0) {
 163             /* Run out of descriptors to transmit.  */
 164             break;
 165         }
 166         len = bd.length;
 167         if (frame_size + len > FEC_MAX_FRAME_SIZE) {
 168             len = FEC_MAX_FRAME_SIZE - frame_size;
 169             s->eir |= FEC_INT_BABT;
 170         }
 171         cpu_physical_memory_read(bd.data, ptr, len);
 172         ptr += len;
 173         frame_size += len;
 174         if (bd.flags & FEC_BD_L) {
 175             /* Last buffer in frame.  */
 176             DPRINTF("Sending packet\n");
 177             qemu_send_packet(qemu_get_queue(s->nic), frame, len);
 178             ptr = frame;
 179             frame_size = 0;
 180             s->eir |= FEC_INT_TXF;
 181         }
 182         s->eir |= FEC_INT_TXB;
 183         bd.flags &= ~FEC_BD_R;
 184         /* Write back the modified descriptor.  */
 185         mcf_fec_write_bd(&bd, addr);
 186         /* Advance to the next descriptor.  */
 187         if ((bd.flags & FEC_BD_W) != 0) {
 188             addr = s->etdsr;
 189         } else {
 190             addr += 8;
 191         }
 192     }
 193     s->tx_descriptor = addr;
 194 }
 195
 196 static void mcf_fec_enable_rx(mcf_fec_state *s)
 197 {
 198     mcf_fec_bd bd;
 199
 200     mcf_fec_read_bd(&bd, s->rx_descriptor);
 201     s->rx_enabled = ((bd.flags & FEC_BD_E) != 0);
 202     if (!s->rx_enabled)
 203         DPRINTF("RX buffer full\n");
 204 }
 205
 206 static void mcf_fec_reset(mcf_fec_state *s)
 207 {
 208     s->eir = 0;
 209     s->eimr = 0;
 210     s->rx_enabled = 0;
 211     s->ecr = 0;
 212     s->mscr = 0;
 213     s->rcr = 0x05ee0001;
 214     s->tcr = 0;
 215     s->tfwr = 0;
 216     s->rfsr = 0x500;
 217 }
 218
 219 static uint64_t mcf_fec_read(void *opaque, hwaddr addr,
 220                              unsigned size)
 221 {
 222     mcf_fec_state *s = (mcf_fec_state *)opaque;
 223     switch (addr & 0x3ff) {
 224     case 0x004: return s->eir;
 225     case 0x008: return s->eimr;
 226     case 0x010: return s->rx_enabled ? (1 << 24) : 0; /* RDAR */
 227     case 0x014: return 0; /* TDAR */
 228     case 0x024: return s->ecr;
 229     case 0x040: return s->mmfr;
 230     case 0x044: return s->mscr;
 231     case 0x064: return 0; /* MIBC */
 232     case 0x084: return s->rcr;
 233     case 0x0c4: return s->tcr;
 234     case 0x0e4: /* PALR */
 235         return (s->conf.macaddr.a[0] << 24) | (s->conf.macaddr.a[1] << 16)
 236               | (s->conf.macaddr.a[2] << 8) | s->conf.macaddr.a[3];
 237         break;
 238     case 0x0e8: /* PAUR */
 239         return (s->conf.macaddr.a[4] << 24) | (s->conf.macaddr.a[5] << 16) | 0x8808;
 240     case 0x0ec: return 0x10000; /* OPD */
 241     case 0x118: return 0;
 242     case 0x11c: return 0;
 243     case 0x120: return 0;
 244     case 0x124: return 0;
 245     case 0x144: return s->tfwr;
 246     case 0x14c: return 0x600;
 247     case 0x150: return s->rfsr;
 248     case 0x180: return s->erdsr;
 249     case 0x184: return s->etdsr;
 250     case 0x188: return s->emrbr;
 251     default:
 252         hw_error("mcf_fec_read: Bad address 0x%x\n", (int)addr);
 253         return 0;
 254     }
 255 }
 256
 257 static void mcf_fec_write(void *opaque, hwaddr addr,
 258                           uint64_t value, unsigned size)
 259 {
 260     mcf_fec_state *s = (mcf_fec_state *)opaque;
 261     switch (addr & 0x3ff) {
 262     case 0x004:
 263         s->eir &= ~value;
 264         break;
 265     case 0x008:
 266         s->eimr = value;
 267         break;
 268     case 0x010: /* RDAR */
 269         if ((s->ecr & FEC_EN) && !s->rx_enabled) {
 270             DPRINTF("RX enable\n");
 271             mcf_fec_enable_rx(s);
 272         }
 273         break;
 274     case 0x014: /* TDAR */
 275         if (s->ecr & FEC_EN) {
 276             mcf_fec_do_tx(s);
 277         }
 278         break;
 279     case 0x024:
 280         s->ecr = value;
 281         if (value & FEC_RESET) {
 282             DPRINTF("Reset\n");
 283             mcf_fec_reset(s);
 284         }
 285         if ((s->ecr & FEC_EN) == 0) {
 286             s->rx_enabled = 0;
 287         }
 288         break;
 289     case 0x040:
 290         /* TODO: Implement MII.  */
 291         s->mmfr = value;
 292         break;
 293     case 0x044:
 294         s->mscr = value & 0xfe;
 295         break;
 296     case 0x064:
 297         /* TODO: Implement MIB.  */
 298         break;
 299     case 0x084:
 300         s->rcr = value & 0x07ff003f;
 301         /* TODO: Implement LOOP mode.  */
 302         break;
 303     case 0x0c4: /* TCR */
 304         /* We transmit immediately, so raise GRA immediately.  */
 305         s->tcr = value;
 306         if (value & 1)
 307             s->eir |= FEC_INT_GRA;
 308         break;
 309     case 0x0e4: /* PALR */
 310         s->conf.macaddr.a[0] = value >> 24;
 311         s->conf.macaddr.a[1] = value >> 16;
 312         s->conf.macaddr.a[2] = value >> 8;
 313         s->conf.macaddr.a[3] = value;
 314         break;
 315     case 0x0e8: /* PAUR */
 316         s->conf.macaddr.a[4] = value >> 24;
 317         s->conf.macaddr.a[5] = value >> 16;
 318         break;
 319     case 0x0ec:
 320         /* OPD */
 321         break;
 322     case 0x118:
 323     case 0x11c:
 324     case 0x120:
 325     case 0x124:
 326         /* TODO: implement MAC hash filtering.  */
 327         break;
 328     case 0x144:
 329         s->tfwr = value & 3;
 330         break;
 331     case 0x14c:
 332         /* FRBR writes ignored.  */
 333         break;
 334     case 0x150:
 335         s->rfsr = (value & 0x3fc) | 0x400;
 336         break;
 337     case 0x180:
 338         s->erdsr = value & ~3;
 339         s->rx_descriptor = s->erdsr;
 340         break;
 341     case 0x184:
 342         s->etdsr = value & ~3;
 343         s->tx_descriptor = s->etdsr;
 344         break;
 345     case 0x188:
 346         s->emrbr = value & 0x7f0;
 347         break;
 348     default:
 349         hw_error("mcf_fec_write Bad address 0x%x\n", (int)addr);
 350     }
 351     mcf_fec_update(s);
 352 }
 353
 354 static int mcf_fec_can_receive(NetClientState *nc)
 355 {
 356     mcf_fec_state *s = qemu_get_nic_opaque(nc);
 357     return s->rx_enabled;
 358 }
 359
 360 static ssize_t mcf_fec_receive(NetClientState *nc, const uint8_t *buf, size_t size)
 361 {
 362     mcf_fec_state *s = qemu_get_nic_opaque(nc);
 363     mcf_fec_bd bd;
 364     uint32_t flags = 0;
 365     uint32_t addr;
 366     uint32_t crc;
 367     uint32_t buf_addr;
 368     uint8_t *crc_ptr;
 369     unsigned int buf_len;
 370
 371     DPRINTF("do_rx len %d\n", size);
 372     if (!s->rx_enabled) {
 373         fprintf(stderr, "mcf_fec_receive: Unexpected packet\n");
 374     }
 375     /* 4 bytes for the CRC.  */
 376     size += 4;
 377     crc = cpu_to_be32(crc32(~0, buf, size));
 378     crc_ptr = (uint8_t *)&crc;
 379     /* Huge frames are truncted.  */
 380     if (size > FEC_MAX_FRAME_SIZE) {
 381         size = FEC_MAX_FRAME_SIZE;
 382         flags |= FEC_BD_TR | FEC_BD_LG;
 383     }
 384     /* Frames larger than the user limit just set error flags.  */
 385     if (size > (s->rcr >> 16)) {
 386         flags |= FEC_BD_LG;
 387     }
 388     addr = s->rx_descriptor;
 389     while (size > 0) {
 390         mcf_fec_read_bd(&bd, addr);
 391         if ((bd.flags & FEC_BD_E) == 0) {
 392             /* No descriptors available.  Bail out.  */
 393             /* FIXME: This is wrong.  We should probably either save the
 394                remainder for when more RX buffers are available, or
 395                flag an error.  */
 396             fprintf(stderr, "mcf_fec: Lost end of frame\n");
 397             break;
 398         }
 399         buf_len = (size <= s->emrbr) ? size: s->emrbr;
 400         bd.length = buf_len;
 401         size -= buf_len;
 402         DPRINTF("rx_bd %x length %d\n", addr, bd.length);
 403         /* The last 4 bytes are the CRC.  */
 404         if (size < 4)
 405             buf_len += size - 4;
 406         buf_addr = bd.data;
 407         cpu_physical_memory_write(buf_addr, buf, buf_len);
 408         buf += buf_len;
 409         if (size < 4) {
 410             cpu_physical_memory_write(buf_addr + buf_len, crc_ptr, 4 - size);
 411             crc_ptr += 4 - size;
 412         }
 413         bd.flags &= ~FEC_BD_E;
 414         if (size == 0) {
 415             /* Last buffer in frame.  */
 416             bd.flags |= flags | FEC_BD_L;
 417             DPRINTF("rx frame flags %04x\n", bd.flags);
 418             s->eir |= FEC_INT_RXF;
 419         } else {
 420             s->eir |= FEC_INT_RXB;
 421         }
 422         mcf_fec_write_bd(&bd, addr);
 423         /* Advance to the next descriptor.  */
 424         if ((bd.flags & FEC_BD_W) != 0) {
 425             addr = s->erdsr;
 426         } else {
 427             addr += 8;
 428         }
 429     }
 430     s->rx_descriptor = addr;
 431     mcf_fec_enable_rx(s);
 432     mcf_fec_update(s);
 433     return size;
 434 }
 435
 436 static const MemoryRegionOps mcf_fec_ops = {
 437     .read = mcf_fec_read,
 438     .write = mcf_fec_write,
 439     .endianness = DEVICE_NATIVE_ENDIAN,
 440 };
 441
 442 static void mcf_fec_cleanup(NetClientState *nc)
 443 {
 444     mcf_fec_state *s = qemu_get_nic_opaque(nc);
 445
 446     memory_region_del_subregion(s->sysmem, &s->iomem);
 447     memory_region_destroy(&s->iomem);
 448
 449     g_free(s);
 450 }
 451
 452 static NetClientInfo net_mcf_fec_info = {
 453     .type = NET_CLIENT_OPTIONS_KIND_NIC,
 454     .size = sizeof(NICState),
 455     .can_receive = mcf_fec_can_receive,
 456     .receive = mcf_fec_receive,
 457     .cleanup = mcf_fec_cleanup,
 458 };
 459
 460 void mcf_fec_init(MemoryRegion *sysmem, NICInfo *nd,
 461                   hwaddr base, qemu_irq *irq)
 462 {
 463     mcf_fec_state *s;
 464
 465     qemu_check_nic_model(nd, "mcf_fec");
 466
 467     s = (mcf_fec_state *)g_malloc0(sizeof(mcf_fec_state));
 468     s->sysmem = sysmem;
 469     s->irq = irq;
 470
 471     memory_region_init_io(&s->iomem, &mcf_fec_ops, s, "fec", 0x400);
 472     memory_region_add_subregion(sysmem, base, &s->iomem);
 473
 474     s->conf.macaddr = nd->macaddr;
 475     s->conf.peers.ncs[0] = nd->netdev;
 476
 477     s->nic = qemu_new_nic(&net_mcf_fec_info, &s->conf, nd->model, nd->name, s);
 478
 479     qemu_format_nic_info_str(qemu_get_queue(s->nic), s->conf.macaddr.a);
 480 }