1 /* if_en.c 4.44 82/03/28 */ 2 3 #include "en.h" 4 5 /* 6 * Xerox prototype (3 Mb) Ethernet interface driver. 7 */ 8 9 #include "../h/param.h" 10 #include "../h/systm.h" 11 #include "../h/mbuf.h" 12 #include "../h/pte.h" 13 #include "../h/buf.h" 14 #include "../h/protosw.h" 15 #include "../h/socket.h" 16 #include "../h/ubareg.h" 17 #include "../h/ubavar.h" 18 #include "../h/enreg.h" 19 #include "../h/cpu.h" 20 #include "../h/mtpr.h" 21 #include "../h/vmmac.h" 22 #include "../net/in.h" 23 #include "../net/in_systm.h" 24 #include "../net/if.h" 25 #include "../net/if_en.h" 26 #include "../net/if_uba.h" 27 #include "../net/ip.h" 28 #include "../net/ip_var.h" 29 #include "../net/pup.h" 30 31 #define ENMTU (1024+512) 32 33 int enprobe(), enattach(), enrint(), enxint(), encollide(); 34 struct uba_device *eninfo[NEN]; 35 u_short enstd[] = { 0 }; 36 struct uba_driver endriver = 37 { enprobe, 0, enattach, 0, enstd, "en", eninfo }; 38 #define ENUNIT(x) minor(x) 39 40 int eninit(),enoutput(),enreset(); 41 42 /* 43 * Ethernet software status per interface. 44 * 45 * Each interface is referenced by a network interface structure, 46 * es_if, which the routing code uses to locate the interface. 47 * This structure contains the output queue for the interface, its address, ... 48 * We also have, for each interface, a UBA interface structure, which 49 * contains information about the UNIBUS resources held by the interface: 50 * map registers, buffered data paths, etc. Information is cached in this 51 * structure for use by the if_uba.c routines in running the interface 52 * efficiently. 53 */ 54 struct en_softc { 55 struct ifnet es_if; /* network-visible interface */ 56 struct ifuba es_ifuba; /* UNIBUS resources */ 57 short es_delay; /* current output delay */ 58 short es_mask; /* mask for current output delay */ 59 u_char es_lastx; /* host last transmitted to */ 60 short es_oactive; /* is output active? */ 61 short es_olen; /* length of last output */ 62 } en_softc[NEN]; 63 64 /* 65 * Do output DMA to determine interface presence and 66 * interrupt vector. DMA is too short to disturb other hosts. 67 */ 68 enprobe(reg) 69 caddr_t reg; 70 { 71 register int br, cvec; /* r11, r10 value-result */ 72 register struct endevice *addr = (struct endevice *)reg; 73 74 COUNT(ENPROBE); 75 #ifdef lint 76 br = 0; cvec = br; br = cvec; 77 enrint(0); enxint(0); encollide(0); 78 #endif 79 addr->en_istat = 0; 80 addr->en_owc = -1; 81 addr->en_oba = 0; 82 addr->en_ostat = EN_IEN|EN_GO; 83 DELAY(100000); 84 addr->en_ostat = 0; 85 return (1); 86 } 87 88 /* 89 * Interface exists: make available by filling in network interface 90 * record. System will initialize the interface when it is ready 91 * to accept packets. 92 */ 93 enattach(ui) 94 struct uba_device *ui; 95 { 96 register struct en_softc *es = &en_softc[ui->ui_unit]; 97 register struct sockaddr_in *sin; 98 COUNT(ENATTACH); 99 100 es->es_if.if_unit = ui->ui_unit; 101 es->es_if.if_name = "en"; 102 es->es_if.if_mtu = ENMTU; 103 es->es_if.if_net = ui->ui_flags; 104 es->es_if.if_host[0] = 105 (~(((struct endevice *)eninfo[ui->ui_unit]->ui_addr)->en_addr)) & 0xff; 106 sin = (struct sockaddr_in *)&es->es_if.if_addr; 107 sin->sin_family = AF_INET; 108 sin->sin_addr = if_makeaddr(es->es_if.if_net, es->es_if.if_host[0]); 109 sin = (struct sockaddr_in *)&es->es_if.if_broadaddr; 110 sin->sin_family = AF_INET; 111 sin->sin_addr = if_makeaddr(es->es_if.if_net, 0); 112 es->es_if.if_flags = IFF_BROADCAST; 113 es->es_if.if_init = eninit; 114 es->es_if.if_output = enoutput; 115 es->es_if.if_ubareset = enreset; 116 es->es_ifuba.ifu_flags = UBA_NEEDBDP | UBA_NEED16; 117 if_attach(&es->es_if); 118 } 119 120 /* 121 * Reset of interface after UNIBUS reset. 122 * If interface is on specified uba, reset its state. 123 */ 124 enreset(unit, uban) 125 int unit, uban; 126 { 127 register struct uba_device *ui; 128 COUNT(ENRESET); 129 130 if (unit >= NEN || (ui = eninfo[unit]) == 0 || ui->ui_alive == 0 || 131 ui->ui_ubanum != uban) 132 return; 133 printf(" en%d", unit); 134 eninit(unit); 135 } 136 137 /* 138 * Initialization of interface; clear recorded pending 139 * operations, and reinitialize UNIBUS usage. 140 */ 141 eninit(unit) 142 int unit; 143 { 144 register struct en_softc *es = &en_softc[unit]; 145 register struct uba_device *ui = eninfo[unit]; 146 register struct endevice *addr; 147 int s; 148 149 if (if_ubainit(&es->es_ifuba, ui->ui_ubanum, 150 sizeof (struct en_header), (int)btoc(ENMTU)) == 0) { 151 printf("en%d: can't initialize\n", unit); 152 es->es_if.if_flags &= ~IFF_UP; 153 return; 154 } 155 addr = (struct endevice *)ui->ui_addr; 156 addr->en_istat = addr->en_ostat = 0; 157 158 /* 159 * Hang a receive and start any 160 * pending writes by faking a transmit complete. 161 */ 162 s = splimp(); 163 addr->en_iba = es->es_ifuba.ifu_r.ifrw_info; 164 addr->en_iwc = -(sizeof (struct en_header) + ENMTU) >> 1; 165 addr->en_istat = EN_IEN|EN_GO; 166 es->es_oactive = 1; 167 es->es_if.if_flags |= IFF_UP; 168 enxint(unit); 169 splx(s); 170 } 171 172 int enlastdel = 25; 173 174 /* 175 * Start or restart output on interface. 176 * If interface is already active, then this is a retransmit 177 * after a collision, and just restuff registers and delay. 178 * If interface is not already active, get another datagram 179 * to send off of the interface queue, and map it to the interface 180 * before starting the output. 181 */ 182 enstart(dev) 183 dev_t dev; 184 { 185 int unit = ENUNIT(dev); 186 struct uba_device *ui = eninfo[unit]; 187 register struct en_softc *es = &en_softc[unit]; 188 register struct endevice *addr; 189 struct mbuf *m; 190 int dest; 191 COUNT(ENSTART); 192 193 if (es->es_oactive) 194 goto restart; 195 196 /* 197 * Not already active: dequeue another request 198 * and map it to the UNIBUS. If no more requests, 199 * just return. 200 */ 201 IF_DEQUEUE(&es->es_if.if_snd, m); 202 if (m == 0) { 203 es->es_oactive = 0; 204 return; 205 } 206 dest = mtod(m, struct en_header *)->en_dhost; 207 es->es_olen = if_wubaput(&es->es_ifuba, m); 208 209 /* 210 * Ethernet cannot take back-to-back packets (no 211 * buffering in interface. To avoid overrunning 212 * receiver, enforce a small delay (about 1ms) in interface 213 * on successive packets sent to same host. 214 */ 215 if (es->es_lastx && es->es_lastx == dest) 216 es->es_delay = enlastdel; 217 else 218 es->es_lastx = dest; 219 220 restart: 221 /* 222 * Have request mapped to UNIBUS for transmission. 223 * Purge any stale data from this BDP, and start the otput. 224 */ 225 if (es->es_ifuba.ifu_flags & UBA_NEEDBDP) 226 UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_w.ifrw_bdp); 227 addr = (struct endevice *)ui->ui_addr; 228 addr->en_oba = (int)es->es_ifuba.ifu_w.ifrw_info; 229 addr->en_odelay = es->es_delay; 230 addr->en_owc = -((es->es_olen + 1) >> 1); 231 addr->en_ostat = EN_IEN|EN_GO; 232 es->es_oactive = 1; 233 } 234 235 /* 236 * Ethernet interface transmitter interrupt. 237 * Start another output if more data to send. 238 */ 239 enxint(unit) 240 int unit; 241 { 242 register struct uba_device *ui = eninfo[unit]; 243 register struct en_softc *es = &en_softc[unit]; 244 register struct endevice *addr = (struct endevice *)ui->ui_addr; 245 COUNT(ENXINT); 246 247 if (es->es_oactive == 0) 248 return; 249 if (es->es_mask && (addr->en_ostat&EN_OERROR)) { 250 es->es_if.if_oerrors++; 251 if (es->es_if.if_oerrors % 100 == 0) 252 printf("en%d: += 100 output errors\n", unit); 253 endocoll(unit); 254 return; 255 } 256 es->es_if.if_opackets++; 257 es->es_oactive = 0; 258 es->es_delay = 0; 259 es->es_mask = ~0; 260 if (es->es_ifuba.ifu_xtofree) { 261 m_freem(es->es_ifuba.ifu_xtofree); 262 es->es_ifuba.ifu_xtofree = 0; 263 } 264 if (es->es_if.if_snd.ifq_head == 0) { 265 es->es_lastx = 0; 266 return; 267 } 268 enstart(unit); 269 } 270 271 /* 272 * Collision on ethernet interface. Do exponential 273 * backoff, and retransmit. If have backed off all 274 * the way print warning diagnostic, and drop packet. 275 */ 276 encollide(unit) 277 int unit; 278 { 279 struct en_softc *es = &en_softc[unit]; 280 COUNT(ENCOLLIDE); 281 282 es->es_if.if_collisions++; 283 if (es->es_oactive == 0) 284 return; 285 endocoll(unit); 286 } 287 288 endocoll(unit) 289 int unit; 290 { 291 register struct en_softc *es = &en_softc[unit]; 292 293 /* 294 * Es_mask is a 16 bit number with n low zero bits, with 295 * n the number of backoffs. When es_mask is 0 we have 296 * backed off 16 times, and give up. 297 */ 298 if (es->es_mask == 0) { 299 printf("en%d: send error\n", unit); 300 enxint(unit); 301 return; 302 } 303 /* 304 * Another backoff. Restart with delay based on n low bits 305 * of the interval timer. 306 */ 307 es->es_mask <<= 1; 308 es->es_delay = mfpr(ICR) &~ es->es_mask; 309 enstart(unit); 310 } 311 312 struct sockaddr_pup pupsrc = { AF_PUP }; 313 struct sockaddr_pup pupdst = { AF_PUP }; 314 struct sockproto pupproto = { PF_PUP }; 315 /* 316 * Ethernet interface receiver interrupt. 317 * If input error just drop packet. 318 * Otherwise purge input buffered data path and examine 319 * packet to determine type. If can't determine length 320 * from type, then have to drop packet. Othewise decapsulate 321 * packet based on type and pass to type specific higher-level 322 * input routine. 323 */ 324 enrint(unit) 325 int unit; 326 { 327 register struct en_softc *es = &en_softc[unit]; 328 struct endevice *addr = (struct endevice *)eninfo[unit]->ui_addr; 329 register struct en_header *en; 330 struct mbuf *m; 331 int len; 332 register struct ifqueue *inq; 333 int off; 334 COUNT(ENRINT); 335 336 es->es_if.if_ipackets++; 337 338 /* 339 * Purge BDP; drop if input error indicated. 340 */ 341 if (es->es_ifuba.ifu_flags & UBA_NEEDBDP) 342 UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_r.ifrw_bdp); 343 if (addr->en_istat&EN_IERROR) { 344 es->es_if.if_ierrors++; 345 if (es->es_if.if_ierrors % 100 == 0) 346 printf("en%d: += 100 input errors\n", unit); 347 goto setup; 348 } 349 350 /* 351 * Get pointer to ethernet header (in input buffer). 352 * Deal with trailer protocol: if type is PUP trailer 353 * get true type from first 16-bit word past data. 354 * Remember that type was trailer by setting off. 355 */ 356 en = (struct en_header *)(es->es_ifuba.ifu_r.ifrw_addr); 357 #define endataaddr(en, off, type) ((type)(((caddr_t)((en)+1)+(off)))) 358 if (en->en_type >= ENPUP_TRAIL && 359 en->en_type < ENPUP_TRAIL+ENPUP_NTRAILER) { 360 off = (en->en_type - ENPUP_TRAIL) * 512; 361 if (off >= ENMTU) 362 goto setup; /* sanity */ 363 en->en_type = *endataaddr(en, off, u_short *); 364 } else 365 off = 0; 366 367 /* 368 * Attempt to infer packet length from type; 369 * can't deal with packet if can't infer length. 370 */ 371 switch (en->en_type) { 372 373 #ifdef INET 374 case ENPUP_IPTYPE: 375 len = htons((u_short)endataaddr(en, 376 off ? off + sizeof (u_short) : 0, struct ip *)->ip_len); 377 if (off) 378 len += sizeof (u_short); 379 break; 380 #endif 381 #ifdef PUP 382 case ENPUP_PUPTYPE: 383 len = endataaddr(en, off ? off + sizeof (u_short) : 0, 384 struct pup_header *)->pup_length; 385 if (off) 386 len -= sizeof (u_short); 387 break; 388 #endif 389 390 default: 391 printf("en%d: unknown pkt type 0x%x\n", unit, en->en_type); 392 goto setup; 393 } 394 if (len == 0) 395 goto setup; 396 397 /* 398 * Pull packet off interface. Off is nonzero if packet 399 * has trailing header; if_rubaget will then force this header 400 * information to be at the front, but we still have to drop 401 * the two-byte type which is at the front of any trailer data. 402 */ 403 m = if_rubaget(&es->es_ifuba, len, off); 404 if (m == 0) 405 goto setup; 406 if (off) { 407 m->m_off += sizeof (u_short); 408 m->m_len -= sizeof (u_short); 409 } 410 switch (en->en_type) { 411 412 #ifdef INET 413 case ENPUP_IPTYPE: 414 schednetisr(NETISR_IP); 415 inq = &ipintrq; 416 break; 417 #endif 418 #ifdef PUP 419 case ENPUP_PUPTYPE: { 420 struct pup_header *pup = mtod(m, struct pup_header *); 421 422 pupproto.sp_protocol = pup->pup_type; 423 pupdst.spup_addr = pup->pup_dport; 424 pupsrc.spup_addr = pup->pup_sport; 425 raw_input(m, &pupproto, (struct sockaddr *)&pupdst, 426 (struct sockaddr *)&pupsrc); 427 goto setup; 428 } 429 #endif 430 } 431 432 if (IF_QFULL(inq)) { 433 IF_DROP(inq); 434 m_freem(m); 435 } else 436 IF_ENQUEUE(inq, m); 437 438 setup: 439 /* 440 * Reset for next packet. 441 */ 442 addr->en_iba = es->es_ifuba.ifu_r.ifrw_info; 443 addr->en_iwc = -(sizeof (struct en_header) + ENMTU) >> 1; 444 addr->en_istat = EN_IEN|EN_GO; 445 } 446 447 /* 448 * Ethernet output routine. 449 * Encapsulate a packet of type family for the local net. 450 * Use trailer local net encapsulation if enough data in first 451 * packet leaves a multiple of 512 bytes of data in remainder. 452 */ 453 enoutput(ifp, m0, dst) 454 struct ifnet *ifp; 455 struct mbuf *m0; 456 struct sockaddr *dst; 457 { 458 int type, dest, s; 459 register struct mbuf *m = m0; 460 register struct en_header *en; 461 register int off; 462 463 COUNT(ENOUTPUT); 464 switch (dst->sa_family) { 465 466 #ifdef INET 467 case AF_INET: 468 dest = ((struct sockaddr_in *)dst)->sin_addr.s_addr >> 24; 469 off = ntohs((u_short)mtod(m, struct ip *)->ip_len) - m->m_len; 470 if (off > 0 && (off & 0x1ff) == 0 && 471 m->m_off >= MMINOFF + sizeof (u_short)) { 472 type = ENPUP_TRAIL + (off>>9); 473 m->m_off -= sizeof (u_short); 474 m->m_len += sizeof (u_short); 475 *mtod(m, u_short *) = ENPUP_IPTYPE; 476 goto gottrailertype; 477 } 478 type = ENPUP_IPTYPE; 479 off = 0; 480 goto gottype; 481 #endif 482 #ifdef PUP 483 case AF_PUP: 484 dest = ((struct sockaddr_pup *)dst)->spup_addr.pp_host; 485 off = mtod(m, struct pup_header *)->pup_length - m->m_len; 486 if (off > 0 && (off & 0x1ff) == 0 && 487 m->m_off >= MMINOFF + sizeof (u_short)) { 488 type = ENPUP_TRAIL + (off>>9); 489 m->m_off -= sizeof (u_short); 490 m->m_len += sizeof (u_short); 491 *mtod(m, u_short *) = ENPUP_PUPTYPE; 492 goto gottrailertype; 493 } 494 type = ENPUP_PUPTYPE; 495 off = 0; 496 goto gottype; 497 #endif 498 499 default: 500 printf("en%d: can't handle af%d\n", ifp->if_unit, 501 dst->sa_family); 502 m_freem(m0); 503 return (0); 504 } 505 506 gottrailertype: 507 /* 508 * Packet to be sent as trailer: move first packet 509 * (control information) to end of chain. 510 */ 511 while (m->m_next) 512 m = m->m_next; 513 m->m_next = m0; 514 m = m0->m_next; 515 m0->m_next = 0; 516 m0 = m; 517 518 gottype: 519 /* 520 * Add local net header. If no space in first mbuf, 521 * allocate another. 522 */ 523 if (m->m_off > MMAXOFF || 524 MMINOFF + sizeof (struct en_header) > m->m_off) { 525 m = m_get(M_DONTWAIT); 526 if (m == 0) { 527 m_freem(m0); 528 return (0); 529 } 530 m->m_next = m0; 531 m->m_off = MMINOFF; 532 m->m_len = sizeof (struct en_header); 533 } else { 534 m->m_off -= sizeof (struct en_header); 535 m->m_len += sizeof (struct en_header); 536 } 537 en = mtod(m, struct en_header *); 538 en->en_shost = ifp->if_host[0]; 539 en->en_dhost = dest; 540 en->en_type = type; 541 542 /* 543 * Queue message on interface, and start output if interface 544 * not yet active. 545 */ 546 s = splimp(); 547 if (IF_QFULL(&ifp->if_snd)) { 548 IF_DROP(&ifp->if_snd); 549 m_freem(m); 550 splx(s); 551 return (0); 552 } 553 IF_ENQUEUE(&ifp->if_snd, m); 554 if (en_softc[ifp->if_unit].es_oactive == 0) 555 enstart(ifp->if_unit); 556 splx(s); 557 return (1); 558 } 559