1 /* if_en.c 4.66 82/06/14 */ 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 #include "../net/route.h" 31 #include <errno.h> 32 33 #define ENMTU (1024+512) 34 #define ENMRU (1024+512+16) /* 16 is enough to receive trailer */ 35 36 int enprobe(), enattach(), enrint(), enxint(), encollide(); 37 struct uba_device *eninfo[NEN]; 38 u_short enstd[] = { 0 }; 39 struct uba_driver endriver = 40 { enprobe, 0, enattach, 0, enstd, "en", eninfo }; 41 #define ENUNIT(x) minor(x) 42 43 int eninit(),enoutput(),enreset(); 44 45 /* 46 * Ethernet software status per interface. 47 * 48 * Each interface is referenced by a network interface structure, 49 * es_if, which the routing code uses to locate the interface. 50 * This structure contains the output queue for the interface, its address, ... 51 * We also have, for each interface, a UBA interface structure, which 52 * contains information about the UNIBUS resources held by the interface: 53 * map registers, buffered data paths, etc. Information is cached in this 54 * structure for use by the if_uba.c routines in running the interface 55 * efficiently. 56 */ 57 struct en_softc { 58 struct ifnet es_if; /* network-visible interface */ 59 struct ifuba es_ifuba; /* UNIBUS resources */ 60 short es_delay; /* current output delay */ 61 short es_mask; /* mask for current output delay */ 62 short es_lastx; /* host last transmitted to */ 63 short es_oactive; /* is output active? */ 64 short es_olen; /* length of last output */ 65 } en_softc[NEN]; 66 67 /* 68 * Do output DMA to determine interface presence and 69 * interrupt vector. DMA is too short to disturb other hosts. 70 */ 71 enprobe(reg) 72 caddr_t reg; 73 { 74 register int br, cvec; /* r11, r10 value-result */ 75 register struct endevice *addr = (struct endevice *)reg; 76 77 COUNT(ENPROBE); 78 #ifdef lint 79 br = 0; cvec = br; br = cvec; 80 enrint(0); enxint(0); encollide(0); 81 #endif 82 addr->en_istat = 0; 83 addr->en_owc = -1; 84 addr->en_oba = 0; 85 addr->en_ostat = EN_IEN|EN_GO; 86 DELAY(100000); 87 addr->en_ostat = 0; 88 #ifdef ECHACK 89 br = 0x16; 90 #endif 91 return (1); 92 } 93 94 /* 95 * Interface exists: make available by filling in network interface 96 * record. System will initialize the interface when it is ready 97 * to accept packets. 98 */ 99 enattach(ui) 100 struct uba_device *ui; 101 { 102 register struct en_softc *es = &en_softc[ui->ui_unit]; 103 register struct sockaddr_in *sin; 104 COUNT(ENATTACH); 105 106 es->es_if.if_unit = ui->ui_unit; 107 es->es_if.if_name = "en"; 108 es->es_if.if_mtu = ENMTU; 109 es->es_if.if_net = ui->ui_flags; 110 es->es_if.if_host[0] = 111 (~(((struct endevice *)eninfo[ui->ui_unit]->ui_addr)->en_addr)) & 0xff; 112 sin = (struct sockaddr_in *)&es->es_if.if_addr; 113 sin->sin_family = AF_INET; 114 sin->sin_addr = if_makeaddr(es->es_if.if_net, es->es_if.if_host[0]); 115 sin = (struct sockaddr_in *)&es->es_if.if_broadaddr; 116 sin->sin_family = AF_INET; 117 sin->sin_addr = if_makeaddr(es->es_if.if_net, 0); 118 es->es_if.if_flags = IFF_BROADCAST; 119 es->es_if.if_init = eninit; 120 es->es_if.if_output = enoutput; 121 es->es_if.if_ubareset = enreset; 122 es->es_ifuba.ifu_flags = UBA_NEEDBDP | UBA_NEED16 | UBA_CANTWAIT; 123 if_attach(&es->es_if); 124 } 125 126 /* 127 * Reset of interface after UNIBUS reset. 128 * If interface is on specified uba, reset its state. 129 */ 130 enreset(unit, uban) 131 int unit, uban; 132 { 133 register struct uba_device *ui; 134 COUNT(ENRESET); 135 136 if (unit >= NEN || (ui = eninfo[unit]) == 0 || ui->ui_alive == 0 || 137 ui->ui_ubanum != uban) 138 return; 139 printf(" en%d", unit); 140 eninit(unit); 141 } 142 143 /* 144 * Initialization of interface; clear recorded pending 145 * operations, and reinitialize UNIBUS usage. 146 */ 147 eninit(unit) 148 int unit; 149 { 150 register struct en_softc *es = &en_softc[unit]; 151 register struct uba_device *ui = eninfo[unit]; 152 register struct endevice *addr; 153 int s; 154 155 if (if_ubainit(&es->es_ifuba, ui->ui_ubanum, 156 sizeof (struct en_header), (int)btoc(ENMRU)) == 0) { 157 printf("en%d: can't initialize\n", unit); 158 es->es_if.if_flags &= ~IFF_UP; 159 return; 160 } 161 addr = (struct endevice *)ui->ui_addr; 162 addr->en_istat = addr->en_ostat = 0; 163 164 /* 165 * Hang a receive and start any 166 * pending writes by faking a transmit complete. 167 */ 168 s = splimp(); 169 addr->en_iba = es->es_ifuba.ifu_r.ifrw_info; 170 addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1; 171 addr->en_istat = EN_IEN|EN_GO; 172 es->es_oactive = 1; 173 es->es_if.if_flags |= IFF_UP; 174 enxint(unit); 175 splx(s); 176 if_rtinit(&es->es_if, RTF_UP); 177 } 178 179 int enalldelay = 0; 180 int enlastdel = 50; 181 int enlastmask = (~0) << 5; 182 183 /* 184 * Start or restart output on interface. 185 * If interface is already active, then this is a retransmit 186 * after a collision, and just restuff registers and delay. 187 * If interface is not already active, get another datagram 188 * to send off of the interface queue, and map it to the interface 189 * before starting the output. 190 */ 191 enstart(dev) 192 dev_t dev; 193 { 194 int unit = ENUNIT(dev); 195 struct uba_device *ui = eninfo[unit]; 196 register struct en_softc *es = &en_softc[unit]; 197 register struct endevice *addr; 198 struct mbuf *m; 199 int dest; 200 COUNT(ENSTART); 201 202 if (es->es_oactive) 203 goto restart; 204 205 /* 206 * Not already active: dequeue another request 207 * and map it to the UNIBUS. If no more requests, 208 * just return. 209 */ 210 IF_DEQUEUE(&es->es_if.if_snd, m); 211 if (m == 0) { 212 es->es_oactive = 0; 213 return; 214 } 215 dest = mtod(m, struct en_header *)->en_dhost; 216 es->es_olen = if_wubaput(&es->es_ifuba, m); 217 218 /* 219 * Ethernet cannot take back-to-back packets (no 220 * buffering in interface. To help avoid overrunning 221 * receivers, enforce a small delay (about 1ms) in interface: 222 * * between all packets when enalldelay 223 * * whenever last packet was broadcast 224 * * whenever this packet is to same host as last packet 225 */ 226 if (enalldelay || es->es_lastx == 0 || es->es_lastx == dest) { 227 es->es_delay = enlastdel; 228 es->es_mask = enlastmask; 229 } 230 es->es_lastx = dest; 231 232 restart: 233 /* 234 * Have request mapped to UNIBUS for transmission. 235 * Purge any stale data from this BDP, and start the otput. 236 */ 237 if (es->es_ifuba.ifu_flags & UBA_NEEDBDP) 238 UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_w.ifrw_bdp); 239 addr = (struct endevice *)ui->ui_addr; 240 addr->en_oba = (int)es->es_ifuba.ifu_w.ifrw_info; 241 addr->en_odelay = es->es_delay; 242 addr->en_owc = -((es->es_olen + 1) >> 1); 243 addr->en_ostat = EN_IEN|EN_GO; 244 es->es_oactive = 1; 245 } 246 247 /* 248 * Ethernet interface transmitter interrupt. 249 * Start another output if more data to send. 250 */ 251 enxint(unit) 252 int unit; 253 { 254 register struct uba_device *ui = eninfo[unit]; 255 register struct en_softc *es = &en_softc[unit]; 256 register struct endevice *addr = (struct endevice *)ui->ui_addr; 257 COUNT(ENXINT); 258 259 if (es->es_oactive == 0) 260 return; 261 if (es->es_mask && (addr->en_ostat&EN_OERROR)) { 262 es->es_if.if_oerrors++; 263 endocoll(unit); 264 return; 265 } 266 es->es_if.if_opackets++; 267 es->es_oactive = 0; 268 es->es_delay = 0; 269 es->es_mask = ~0; 270 if (es->es_ifuba.ifu_xtofree) { 271 m_freem(es->es_ifuba.ifu_xtofree); 272 es->es_ifuba.ifu_xtofree = 0; 273 } 274 if (es->es_if.if_snd.ifq_head == 0) { 275 es->es_lastx = 256; /* putatively illegal */ 276 return; 277 } 278 enstart(unit); 279 } 280 281 /* 282 * Collision on ethernet interface. Do exponential 283 * backoff, and retransmit. If have backed off all 284 * the way print warning diagnostic, and drop packet. 285 */ 286 encollide(unit) 287 int unit; 288 { 289 struct en_softc *es = &en_softc[unit]; 290 COUNT(ENCOLLIDE); 291 292 es->es_if.if_collisions++; 293 if (es->es_oactive == 0) 294 return; 295 endocoll(unit); 296 } 297 298 endocoll(unit) 299 int unit; 300 { 301 register struct en_softc *es = &en_softc[unit]; 302 303 /* 304 * Es_mask is a 16 bit number with n low zero bits, with 305 * n the number of backoffs. When es_mask is 0 we have 306 * backed off 16 times, and give up. 307 */ 308 if (es->es_mask == 0) { 309 printf("en%d: send error\n", unit); 310 enxint(unit); 311 return; 312 } 313 /* 314 * Another backoff. Restart with delay based on n low bits 315 * of the interval timer. 316 */ 317 es->es_mask <<= 1; 318 es->es_delay = mfpr(ICR) &~ es->es_mask; 319 enstart(unit); 320 } 321 322 struct sockaddr_pup pupsrc = { AF_PUP }; 323 struct sockaddr_pup pupdst = { AF_PUP }; 324 struct sockproto pupproto = { PF_PUP }; 325 /* 326 * Ethernet interface receiver interrupt. 327 * If input error just drop packet. 328 * Otherwise purge input buffered data path and examine 329 * packet to determine type. If can't determine length 330 * from type, then have to drop packet. Othewise decapsulate 331 * packet based on type and pass to type specific higher-level 332 * input routine. 333 */ 334 enrint(unit) 335 int unit; 336 { 337 register struct en_softc *es = &en_softc[unit]; 338 struct endevice *addr = (struct endevice *)eninfo[unit]->ui_addr; 339 register struct en_header *en; 340 struct mbuf *m; 341 int len, plen; short resid; 342 register struct ifqueue *inq; 343 int off; 344 COUNT(ENRINT); 345 346 es->es_if.if_ipackets++; 347 348 /* 349 * Purge BDP; drop if input error indicated. 350 */ 351 if (es->es_ifuba.ifu_flags & UBA_NEEDBDP) 352 UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_r.ifrw_bdp); 353 if (addr->en_istat&EN_IERROR) { 354 es->es_if.if_ierrors++; 355 goto setup; 356 } 357 358 /* 359 * Calculate input data length. 360 * Get pointer to ethernet header (in input buffer). 361 * Deal with trailer protocol: if type is PUP trailer 362 * get true type from first 16-bit word past data. 363 * Remember that type was trailer by setting off. 364 */ 365 resid = addr->en_iwc; 366 if (resid) 367 resid |= 0176000; 368 len = (((sizeof (struct en_header) + ENMRU) >> 1) + resid) << 1; 369 len -= sizeof (struct en_header); 370 if (len > ENMRU) 371 goto setup; /* sanity */ 372 en = (struct en_header *)(es->es_ifuba.ifu_r.ifrw_addr); 373 #define endataaddr(en, off, type) ((type)(((caddr_t)((en)+1)+(off)))) 374 if (en->en_type >= ENPUP_TRAIL && 375 en->en_type < ENPUP_TRAIL+ENPUP_NTRAILER) { 376 off = (en->en_type - ENPUP_TRAIL) * 512; 377 if (off > ENMTU) 378 goto setup; /* sanity */ 379 en->en_type = *endataaddr(en, off, u_short *); 380 resid = *(endataaddr(en, off+2, u_short *)); 381 if (off + resid > len) 382 goto setup; /* sanity */ 383 len = off + resid; 384 } else 385 off = 0; 386 if (len == 0) 387 goto setup; 388 /* 389 * Pull packet off interface. Off is nonzero if packet 390 * has trailing header; if_rubaget will then force this header 391 * information to be at the front, but we still have to drop 392 * the type and length which are at the front of any trailer data. 393 */ 394 m = if_rubaget(&es->es_ifuba, len, off); 395 if (m == 0) 396 goto setup; 397 if (off) { 398 m->m_off += 2 * sizeof (u_short); 399 m->m_len -= 2 * sizeof (u_short); 400 } 401 switch (en->en_type) { 402 403 #ifdef INET 404 case ENPUP_IPTYPE: 405 schednetisr(NETISR_IP); 406 inq = &ipintrq; 407 break; 408 #endif 409 #ifdef PUP 410 case ENPUP_PUPTYPE: { 411 struct pup_header *pup = mtod(m, struct pup_header *); 412 413 pupproto.sp_protocol = pup->pup_type; 414 pupdst.spup_addr = pup->pup_dport; 415 pupsrc.spup_addr = pup->pup_sport; 416 raw_input(m, &pupproto, (struct sockaddr *)&pupsrc, 417 (struct sockaddr *)&pupdst); 418 goto setup; 419 } 420 #endif 421 default: 422 m_freem(m); 423 goto setup; 424 } 425 426 if (IF_QFULL(inq)) { 427 IF_DROP(inq); 428 m_freem(m); 429 } else 430 IF_ENQUEUE(inq, m); 431 432 setup: 433 /* 434 * Reset for next packet. 435 */ 436 addr->en_iba = es->es_ifuba.ifu_r.ifrw_info; 437 addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1; 438 addr->en_istat = EN_IEN|EN_GO; 439 } 440 441 /* 442 * Ethernet output routine. 443 * Encapsulate a packet of type family for the local net. 444 * Use trailer local net encapsulation if enough data in first 445 * packet leaves a multiple of 512 bytes of data in remainder. 446 */ 447 enoutput(ifp, m0, dst) 448 struct ifnet *ifp; 449 struct mbuf *m0; 450 struct sockaddr *dst; 451 { 452 int type, dest, s, error; 453 register struct mbuf *m = m0; 454 register struct en_header *en; 455 register int off; 456 457 COUNT(ENOUTPUT); 458 switch (dst->sa_family) { 459 460 #ifdef INET 461 case AF_INET: 462 dest = ((struct sockaddr_in *)dst)->sin_addr.s_addr; 463 if (dest & 0x00ffff00) { 464 error = EPERM; /* ??? */ 465 goto bad; 466 } 467 dest = (dest >> 24) & 0xff; 468 off = ntohs((u_short)mtod(m, struct ip *)->ip_len) - m->m_len; 469 if (off > 0 && (off & 0x1ff) == 0 && 470 m->m_off >= MMINOFF + 2 * sizeof (u_short)) { 471 type = ENPUP_TRAIL + (off>>9); 472 m->m_off -= 2 * sizeof (u_short); 473 m->m_len += 2 * sizeof (u_short); 474 *mtod(m, u_short *) = ENPUP_IPTYPE; 475 *(mtod(m, u_short *) + 1) = m->m_len; 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 type = ENPUP_PUPTYPE; 486 off = 0; 487 goto gottype; 488 #endif 489 490 default: 491 printf("en%d: can't handle af%d\n", ifp->if_unit, 492 dst->sa_family); 493 error = EAFNOSUPPORT; 494 goto bad; 495 } 496 497 gottrailertype: 498 /* 499 * Packet to be sent as trailer: move first packet 500 * (control information) to end of chain. 501 */ 502 while (m->m_next) 503 m = m->m_next; 504 m->m_next = m0; 505 m = m0->m_next; 506 m0->m_next = 0; 507 m0 = m; 508 509 gottype: 510 /* 511 * Add local net header. If no space in first mbuf, 512 * allocate another. 513 */ 514 if (m->m_off > MMAXOFF || 515 MMINOFF + sizeof (struct en_header) > m->m_off) { 516 m = m_get(M_DONTWAIT); 517 if (m == 0) { 518 error = ENOBUFS; 519 goto bad; 520 } 521 m->m_next = m0; 522 m->m_off = MMINOFF; 523 m->m_len = sizeof (struct en_header); 524 } else { 525 m->m_off -= sizeof (struct en_header); 526 m->m_len += sizeof (struct en_header); 527 } 528 en = mtod(m, struct en_header *); 529 en->en_shost = ifp->if_host[0]; 530 en->en_dhost = dest; 531 en->en_type = type; 532 533 /* 534 * Queue message on interface, and start output if interface 535 * not yet active. 536 */ 537 s = splimp(); 538 if (IF_QFULL(&ifp->if_snd)) { 539 IF_DROP(&ifp->if_snd); 540 error = ENOBUFS; 541 goto qfull; 542 } 543 IF_ENQUEUE(&ifp->if_snd, m); 544 if (en_softc[ifp->if_unit].es_oactive == 0) 545 enstart(ifp->if_unit); 546 splx(s); 547 return (0); 548 qfull: 549 m0 = m; 550 splx(s); 551 bad: 552 m_freem(m0); 553 return (error); 554 } 555