hw/mcf_fec.c

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