1 /* if_en.c 4.36 82/03/03 */ 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 COUNT(ENATTACH); 98 99 es->es_if.if_unit = ui->ui_unit; 100 es->es_if.if_name = "en"; 101 es->es_if.if_mtu = ENMTU; 102 es->es_if.if_net = ui->ui_flags; 103 es->es_if.if_host[0] = 104 (~(((struct endevice *)eninfo[ui->ui_unit]->ui_addr)->en_addr)) & 0xff; 105 #ifdef ENKLUDGE 106 if (es->es_if.if_net == 10) { 107 es->es_if.if_host[0] <<= 16; 108 es->es_if.if_host[0] |= 0x4e; 109 } 110 #endif 111 es->es_if.if_addr = 112 if_makeaddr(es->es_if.if_net, es->es_if.if_host[0]); 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 return; 153 } 154 addr = (struct endevice *)ui->ui_addr; 155 addr->en_istat = addr->en_ostat = 0; 156 157 /* 158 * Hang a receive and start any 159 * pending writes by faking a transmit complete. 160 */ 161 s = splimp(); 162 addr->en_iba = es->es_ifuba.ifu_r.ifrw_info; 163 addr->en_iwc = -(sizeof (struct en_header) + ENMTU) >> 1; 164 addr->en_istat = EN_IEN|EN_GO; 165 es->es_oactive = 1; 166 enxint(unit); 167 splx(s); 168 } 169 170 int enlastdel = 25; 171 172 /* 173 * Start or restart output on interface. 174 * If interface is already active, then this is a retransmit 175 * after a collision, and just restuff registers and delay. 176 * If interface is not already active, get another datagram 177 * to send off of the interface queue, and map it to the interface 178 * before starting the output. 179 */ 180 enstart(dev) 181 dev_t dev; 182 { 183 int unit = ENUNIT(dev); 184 struct uba_device *ui = eninfo[unit]; 185 register struct en_softc *es = &en_softc[unit]; 186 register struct endevice *addr; 187 struct mbuf *m; 188 int dest; 189 COUNT(ENSTART); 190 191 if (es->es_oactive) 192 goto restart; 193 194 /* 195 * Not already active: dequeue another request 196 * and map it to the UNIBUS. If no more requests, 197 * just return. 198 */ 199 IF_DEQUEUE(&es->es_if.if_snd, m); 200 if (m == 0) { 201 es->es_oactive = 0; 202 return; 203 } 204 dest = mtod(m, struct en_header *)->en_dhost; 205 es->es_olen = if_wubaput(&es->es_ifuba, m); 206 207 /* 208 * Ethernet cannot take back-to-back packets (no 209 * buffering in interface. To avoid overrunning 210 * receiver, enforce a small delay (about 1ms) in interface 211 * on successive packets sent to same host. 212 */ 213 if (es->es_lastx && es->es_lastx == dest) 214 es->es_delay = enlastdel; 215 else 216 es->es_lastx = dest; 217 218 restart: 219 /* 220 * Have request mapped to UNIBUS for transmission. 221 * Purge any stale data from this BDP, and start the otput. 222 */ 223 UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_w.ifrw_bdp); 224 addr = (struct endevice *)ui->ui_addr; 225 addr->en_oba = (int)es->es_ifuba.ifu_w.ifrw_info; 226 addr->en_odelay = es->es_delay; 227 addr->en_owc = -((es->es_olen + 1) >> 1); 228 addr->en_ostat = EN_IEN|EN_GO; 229 es->es_oactive = 1; 230 } 231 232 /* 233 * Ethernet interface transmitter interrupt. 234 * Start another output if more data to send. 235 */ 236 enxint(unit) 237 int unit; 238 { 239 register struct uba_device *ui = eninfo[unit]; 240 register struct en_softc *es = &en_softc[unit]; 241 register struct endevice *addr; 242 COUNT(ENXINT); 243 244 if (es->es_oactive == 0) 245 return; 246 addr = (struct endevice *)ui->ui_addr; 247 es->es_if.if_opackets++; 248 es->es_oactive = 0; 249 es->es_delay = 0; 250 es->es_mask = ~0; 251 if (addr->en_ostat&EN_OERROR) { 252 es->es_if.if_oerrors++; 253 printf("en%d: output error\n", unit); 254 } 255 if (es->es_ifuba.ifu_xtofree) { 256 m_freem(es->es_ifuba.ifu_xtofree); 257 es->es_ifuba.ifu_xtofree = 0; 258 } 259 if (es->es_if.if_snd.ifq_head == 0) { 260 es->es_lastx = 0; 261 return; 262 } 263 enstart(unit); 264 } 265 266 /* 267 * Collision on ethernet interface. Do exponential 268 * backoff, and retransmit. If have backed off all 269 * the way printing warning diagnostic, and drop packet. 270 */ 271 encollide(unit) 272 int unit; 273 { 274 register struct en_softc *es = &en_softc[unit]; 275 COUNT(ENCOLLIDE); 276 277 es->es_if.if_collisions++; 278 if (es->es_oactive == 0) 279 return; 280 /* 281 * Es_mask is a 16 bit number with n low zero bits, with 282 * n the number of backoffs. When es_mask is 0 we have 283 * backed off 16 times, and give up. 284 */ 285 if (es->es_mask == 0) { 286 printf("en%d: send error\n", unit); 287 enxint(unit); 288 return; 289 } 290 /* 291 * Another backoff. Restart with delay based on n low bits 292 * of the interval timer. 293 */ 294 es->es_mask <<= 1; 295 es->es_delay = mfpr(ICR) &~ es->es_mask; 296 enstart(unit); 297 } 298 299 int enprintierrors; 300 struct sockaddr_pup pupsrc = { AF_PUP }; 301 struct sockaddr_pup pupdst = { AF_PUP }; 302 struct sockproto pupproto = { PF_PUP }; 303 /* 304 * Ethernet interface receiver interrupt. 305 * If input error just drop packet. 306 * Otherwise purge input buffered data path and examine 307 * packet to determine type. If can't determine length 308 * from type, then have to drop packet. Othewise decapsulate 309 * packet based on type and pass to type specific higher-level 310 * input routine. 311 */ 312 enrint(unit) 313 int unit; 314 { 315 register struct en_softc *es = &en_softc[unit]; 316 struct endevice *addr = (struct endevice *)eninfo[unit]->ui_addr; 317 register struct en_header *en; 318 struct mbuf *m; 319 int len; 320 register struct ifqueue *inq; 321 int off; 322 COUNT(ENRINT); 323 324 es->es_if.if_ipackets++; 325 326 /* 327 * Purge BDP; drop if input error indicated. 328 */ 329 UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_r.ifrw_bdp); 330 if (addr->en_istat&EN_IERROR) { 331 es->es_if.if_ierrors++; 332 if (enprintierrors) 333 printf("en%d: input error\n", unit); 334 goto setup; 335 } 336 337 /* 338 * Get pointer to ethernet header (in input buffer). 339 * Deal with trailer protocol: if type is PUP trailer 340 * get true type from first 16-bit word past data. 341 * Remember that type was trailer by setting off. 342 */ 343 en = (struct en_header *)(es->es_ifuba.ifu_r.ifrw_addr); 344 #define endataaddr(en, off, type) ((type)(((caddr_t)((en)+1)+(off)))) 345 if (en->en_type >= ENPUP_TRAIL && 346 en->en_type < ENPUP_TRAIL+ENPUP_NTRAILER) { 347 off = (en->en_type - ENPUP_TRAIL) * 512; 348 if (off >= ENMTU) 349 goto setup; /* sanity */ 350 en->en_type = *endataaddr(en, off, u_short *); 351 } else 352 off = 0; 353 354 /* 355 * Attempt to infer packet length from type; 356 * can't deal with packet if can't infer length. 357 */ 358 switch (en->en_type) { 359 360 #ifdef INET 361 case ENPUP_IPTYPE: 362 len = htons((u_short)endataaddr(en, off ? off+2 : 0, struct ip *)->ip_len); 363 if (off) 364 len += 2; 365 break; 366 #endif 367 #ifdef PUP 368 case ENPUP_PUPTYPE: 369 len = endataaddr(en, off, struct pup_header *)->pup_length; 370 if (off) 371 len -= 2; 372 break; 373 #endif 374 375 default: 376 printf("en%d: unknown pkt type 0x%x\n", unit, en->en_type); 377 goto setup; 378 } 379 if (len == 0) 380 goto setup; 381 382 /* 383 * Pull packet off interface. Off is nonzero if packet 384 * has trailing header; if_rubaget will then force this header 385 * information to be at the front, but we still have to drop 386 * the two-byte type which is at the front of any trailer data. 387 */ 388 m = if_rubaget(&es->es_ifuba, len, off); 389 if (m == 0) 390 goto setup; 391 if (off) { 392 m->m_off += 2; 393 m->m_len -= 2; 394 } 395 switch (en->en_type) { 396 397 #ifdef INET 398 case ENPUP_IPTYPE: 399 setipintr(); 400 inq = &ipintrq; 401 break; 402 #endif 403 case ENPUP_PUPTYPE: { 404 struct pup_header *pup = mtod(m, struct pup_header *); 405 406 pupproto.sp_protocol = pup->pup_type; 407 pupdst.spup_addr = pup->pup_dport; 408 pupsrc.spup_addr = pup->pup_sport; 409 raw_input(m, &pupproto, &pupdst, &pupsrc); 410 goto setup; 411 } 412 } 413 IF_ENQUEUE(inq, m); 414 415 setup: 416 /* 417 * Reset for next packet. 418 */ 419 addr->en_iba = es->es_ifuba.ifu_r.ifrw_info; 420 addr->en_iwc = -(sizeof (struct en_header) + ENMTU) >> 1; 421 addr->en_istat = EN_IEN|EN_GO; 422 } 423 424 /* 425 * Ethernet output routine. 426 * Encapsulate a packet of type family for the local net. 427 * Use trailer local net encapsulation if enough data in first 428 * packet leaves a multiple of 512 bytes of data in remainder. 429 */ 430 enoutput(ifp, m0, pf) 431 struct ifnet *ifp; 432 struct mbuf *m0; 433 int pf; 434 { 435 int type, dest; 436 register struct mbuf *m = m0; 437 register struct en_header *en; 438 int s; 439 440 COUNT(ENOUTPUT); 441 switch (pf) { 442 443 #ifdef INET 444 case PF_INET: { 445 register struct ip *ip = mtod(m0, struct ip *); 446 int off; 447 448 #ifndef ENKLUDGE 449 dest = ip->ip_dst.s_addr >> 24; 450 #else 451 dest = (ip->ip_dst.s_addr >> 8) & 0xff; 452 #endif 453 off = ntohs((u_short)ip->ip_len) - m->m_len; 454 #ifndef ENKLUDGE 455 if (off > 0 && (off & 0x1ff) == 0 && m->m_off >= MMINOFF + 2) { 456 type = ENPUP_TRAIL + (off>>9); 457 m->m_off -= 2; 458 m->m_len += 2; 459 *mtod(m, u_short *) = ENPUP_IPTYPE; 460 goto gottrailertype; 461 } 462 #endif 463 type = ENPUP_IPTYPE; 464 off = 0; 465 goto gottype; 466 } 467 #endif 468 #ifdef PUP 469 case PF_PUP: { 470 register struct pup_header *pup = mtod(m, struct pup_header *); 471 472 dest = pup->pup_dhost; 473 off = pup->pup_length - m->m_len; 474 if (off > 0 && (off & 0x1ff) == 0 && m->m_off >= MMINOFF + 2) { 475 type = ENPUP_TRAIL + (off>>9); 476 m->m_off -= 2; 477 m->m_len += 2; 478 *mtod(m, u_short *) = ENPUP_PUPTYPE; 479 goto gottrailertype; 480 } 481 type = ENPUP_PUPTYPE; 482 off = 0; 483 goto gottype; 484 } 485 #endif 486 487 default: 488 printf("en%d: can't encapsulate pf%d\n", ifp->if_unit, pf); 489 m_freem(m0); 490 return (0); 491 } 492 493 gottrailertype: 494 /* 495 * Packet to be sent as trailer: move first packet 496 * (control information) to end of chain. 497 */ 498 while (m->m_next) 499 m = m->m_next; 500 m->m_next = m0; 501 m = m0->m_next; 502 m0->m_next = 0; 503 m0 = m; 504 505 gottype: 506 /* 507 * Add local net header. If no space in first mbuf, 508 * allocate another. 509 */ 510 if (m->m_off > MMAXOFF || 511 MMINOFF + sizeof (struct en_header) > m->m_off) { 512 m = m_get(M_DONTWAIT); 513 if (m == 0) { 514 m_freem(m0); 515 return (0); 516 } 517 m->m_next = m0; 518 m->m_off = MMINOFF; 519 m->m_len = sizeof (struct en_header); 520 } else { 521 m->m_off -= sizeof (struct en_header); 522 m->m_len += sizeof (struct en_header); 523 } 524 en = mtod(m, struct en_header *); 525 en->en_shost = ifp->if_host[0]; 526 en->en_dhost = dest; 527 en->en_type = type; 528 529 /* 530 * Queue message on interface, and start output if interface 531 * not yet active. 532 */ 533 s = splimp(); 534 IF_ENQUEUE(&ifp->if_snd, m); 535 if (en_softc[ifp->if_unit].es_oactive == 0) 536 enstart(ifp->if_unit); 537 splx(s); 538 return (1); 539 } 540