1 /* if_en.c 4.67 82/06/20 */ 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 #ifdef lint 78 br = 0; cvec = br; br = cvec; 79 enrint(0); enxint(0); encollide(0); 80 #endif 81 addr->en_istat = 0; 82 addr->en_owc = -1; 83 addr->en_oba = 0; 84 addr->en_ostat = EN_IEN|EN_GO; 85 DELAY(100000); 86 addr->en_ostat = 0; 87 #ifdef ECHACK 88 br = 0x16; 89 #endif 90 return (1); 91 } 92 93 /* 94 * Interface exists: make available by filling in network interface 95 * record. System will initialize the interface when it is ready 96 * to accept packets. 97 */ 98 enattach(ui) 99 struct uba_device *ui; 100 { 101 register struct en_softc *es = &en_softc[ui->ui_unit]; 102 register struct sockaddr_in *sin; 103 104 es->es_if.if_unit = ui->ui_unit; 105 es->es_if.if_name = "en"; 106 es->es_if.if_mtu = ENMTU; 107 es->es_if.if_net = ui->ui_flags; 108 es->es_if.if_host[0] = 109 (~(((struct endevice *)eninfo[ui->ui_unit]->ui_addr)->en_addr)) & 0xff; 110 sin = (struct sockaddr_in *)&es->es_if.if_addr; 111 sin->sin_family = AF_INET; 112 sin->sin_addr = if_makeaddr(es->es_if.if_net, es->es_if.if_host[0]); 113 sin = (struct sockaddr_in *)&es->es_if.if_broadaddr; 114 sin->sin_family = AF_INET; 115 sin->sin_addr = if_makeaddr(es->es_if.if_net, 0); 116 es->es_if.if_flags = IFF_BROADCAST; 117 es->es_if.if_init = eninit; 118 es->es_if.if_output = enoutput; 119 es->es_if.if_ubareset = enreset; 120 es->es_ifuba.ifu_flags = UBA_NEEDBDP | UBA_NEED16 | UBA_CANTWAIT; 121 if_attach(&es->es_if); 122 } 123 124 /* 125 * Reset of interface after UNIBUS reset. 126 * If interface is on specified uba, reset its state. 127 */ 128 enreset(unit, uban) 129 int unit, uban; 130 { 131 register struct uba_device *ui; 132 133 if (unit >= NEN || (ui = eninfo[unit]) == 0 || ui->ui_alive == 0 || 134 ui->ui_ubanum != uban) 135 return; 136 printf(" en%d", unit); 137 eninit(unit); 138 } 139 140 /* 141 * Initialization of interface; clear recorded pending 142 * operations, and reinitialize UNIBUS usage. 143 */ 144 eninit(unit) 145 int unit; 146 { 147 register struct en_softc *es = &en_softc[unit]; 148 register struct uba_device *ui = eninfo[unit]; 149 register struct endevice *addr; 150 int s; 151 152 if (if_ubainit(&es->es_ifuba, ui->ui_ubanum, 153 sizeof (struct en_header), (int)btoc(ENMRU)) == 0) { 154 printf("en%d: can't initialize\n", unit); 155 es->es_if.if_flags &= ~IFF_UP; 156 return; 157 } 158 addr = (struct endevice *)ui->ui_addr; 159 addr->en_istat = addr->en_ostat = 0; 160 161 /* 162 * Hang a receive and start any 163 * pending writes by faking a transmit complete. 164 */ 165 s = splimp(); 166 addr->en_iba = es->es_ifuba.ifu_r.ifrw_info; 167 addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1; 168 addr->en_istat = EN_IEN|EN_GO; 169 es->es_oactive = 1; 170 es->es_if.if_flags |= IFF_UP; 171 enxint(unit); 172 splx(s); 173 if_rtinit(&es->es_if, RTF_UP); 174 } 175 176 int enalldelay = 0; 177 int enlastdel = 50; 178 int enlastmask = (~0) << 5; 179 180 /* 181 * Start or restart output on interface. 182 * If interface is already active, then this is a retransmit 183 * after a collision, and just restuff registers and delay. 184 * If interface is not already active, get another datagram 185 * to send off of the interface queue, and map it to the interface 186 * before starting the output. 187 */ 188 enstart(dev) 189 dev_t dev; 190 { 191 int unit = ENUNIT(dev); 192 struct uba_device *ui = eninfo[unit]; 193 register struct en_softc *es = &en_softc[unit]; 194 register struct endevice *addr; 195 struct mbuf *m; 196 int dest; 197 198 if (es->es_oactive) 199 goto restart; 200 201 /* 202 * Not already active: dequeue another request 203 * and map it to the UNIBUS. If no more requests, 204 * just return. 205 */ 206 IF_DEQUEUE(&es->es_if.if_snd, m); 207 if (m == 0) { 208 es->es_oactive = 0; 209 return; 210 } 211 dest = mtod(m, struct en_header *)->en_dhost; 212 es->es_olen = if_wubaput(&es->es_ifuba, m); 213 214 /* 215 * Ethernet cannot take back-to-back packets (no 216 * buffering in interface. To help avoid overrunning 217 * receivers, enforce a small delay (about 1ms) in interface: 218 * * between all packets when enalldelay 219 * * whenever last packet was broadcast 220 * * whenever this packet is to same host as last packet 221 */ 222 if (enalldelay || es->es_lastx == 0 || es->es_lastx == dest) { 223 es->es_delay = enlastdel; 224 es->es_mask = enlastmask; 225 } 226 es->es_lastx = dest; 227 228 restart: 229 /* 230 * Have request mapped to UNIBUS for transmission. 231 * Purge any stale data from this BDP, and start the otput. 232 */ 233 if (es->es_ifuba.ifu_flags & UBA_NEEDBDP) 234 UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_w.ifrw_bdp); 235 addr = (struct endevice *)ui->ui_addr; 236 addr->en_oba = (int)es->es_ifuba.ifu_w.ifrw_info; 237 addr->en_odelay = es->es_delay; 238 addr->en_owc = -((es->es_olen + 1) >> 1); 239 addr->en_ostat = EN_IEN|EN_GO; 240 es->es_oactive = 1; 241 } 242 243 /* 244 * Ethernet interface transmitter interrupt. 245 * Start another output if more data to send. 246 */ 247 enxint(unit) 248 int unit; 249 { 250 register struct uba_device *ui = eninfo[unit]; 251 register struct en_softc *es = &en_softc[unit]; 252 register struct endevice *addr = (struct endevice *)ui->ui_addr; 253 254 if (es->es_oactive == 0) 255 return; 256 if (es->es_mask && (addr->en_ostat&EN_OERROR)) { 257 es->es_if.if_oerrors++; 258 endocoll(unit); 259 return; 260 } 261 es->es_if.if_opackets++; 262 es->es_oactive = 0; 263 es->es_delay = 0; 264 es->es_mask = ~0; 265 if (es->es_ifuba.ifu_xtofree) { 266 m_freem(es->es_ifuba.ifu_xtofree); 267 es->es_ifuba.ifu_xtofree = 0; 268 } 269 if (es->es_if.if_snd.ifq_head == 0) { 270 es->es_lastx = 256; /* putatively illegal */ 271 return; 272 } 273 enstart(unit); 274 } 275 276 /* 277 * Collision on ethernet interface. Do exponential 278 * backoff, and retransmit. If have backed off all 279 * the way print warning diagnostic, and drop packet. 280 */ 281 encollide(unit) 282 int unit; 283 { 284 struct en_softc *es = &en_softc[unit]; 285 286 es->es_if.if_collisions++; 287 if (es->es_oactive == 0) 288 return; 289 endocoll(unit); 290 } 291 292 endocoll(unit) 293 int unit; 294 { 295 register struct en_softc *es = &en_softc[unit]; 296 297 /* 298 * Es_mask is a 16 bit number with n low zero bits, with 299 * n the number of backoffs. When es_mask is 0 we have 300 * backed off 16 times, and give up. 301 */ 302 if (es->es_mask == 0) { 303 printf("en%d: send error\n", unit); 304 enxint(unit); 305 return; 306 } 307 /* 308 * Another backoff. Restart with delay based on n low bits 309 * of the interval timer. 310 */ 311 es->es_mask <<= 1; 312 es->es_delay = mfpr(ICR) &~ es->es_mask; 313 enstart(unit); 314 } 315 316 struct sockaddr_pup pupsrc = { AF_PUP }; 317 struct sockaddr_pup pupdst = { AF_PUP }; 318 struct sockproto pupproto = { PF_PUP }; 319 /* 320 * Ethernet interface receiver interrupt. 321 * If input error just drop packet. 322 * Otherwise purge input buffered data path and examine 323 * packet to determine type. If can't determine length 324 * from type, then have to drop packet. Othewise decapsulate 325 * packet based on type and pass to type specific higher-level 326 * input routine. 327 */ 328 enrint(unit) 329 int unit; 330 { 331 register struct en_softc *es = &en_softc[unit]; 332 struct endevice *addr = (struct endevice *)eninfo[unit]->ui_addr; 333 register struct en_header *en; 334 struct mbuf *m; 335 int len, plen; short resid; 336 register struct ifqueue *inq; 337 int off; 338 339 es->es_if.if_ipackets++; 340 341 /* 342 * Purge BDP; drop if input error indicated. 343 */ 344 if (es->es_ifuba.ifu_flags & UBA_NEEDBDP) 345 UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_r.ifrw_bdp); 346 if (addr->en_istat&EN_IERROR) { 347 es->es_if.if_ierrors++; 348 goto setup; 349 } 350 351 /* 352 * Calculate input data length. 353 * Get pointer to ethernet header (in input buffer). 354 * Deal with trailer protocol: if type is PUP trailer 355 * get true type from first 16-bit word past data. 356 * Remember that type was trailer by setting off. 357 */ 358 resid = addr->en_iwc; 359 if (resid) 360 resid |= 0176000; 361 len = (((sizeof (struct en_header) + ENMRU) >> 1) + resid) << 1; 362 len -= sizeof (struct en_header); 363 if (len > ENMRU) 364 goto setup; /* sanity */ 365 en = (struct en_header *)(es->es_ifuba.ifu_r.ifrw_addr); 366 #define endataaddr(en, off, type) ((type)(((caddr_t)((en)+1)+(off)))) 367 if (en->en_type >= ENPUP_TRAIL && 368 en->en_type < ENPUP_TRAIL+ENPUP_NTRAILER) { 369 off = (en->en_type - ENPUP_TRAIL) * 512; 370 if (off > ENMTU) 371 goto setup; /* sanity */ 372 en->en_type = *endataaddr(en, off, u_short *); 373 resid = *(endataaddr(en, off+2, u_short *)); 374 if (off + resid > len) 375 goto setup; /* sanity */ 376 len = off + resid; 377 } else 378 off = 0; 379 if (len == 0) 380 goto setup; 381 /* 382 * Pull packet off interface. Off is nonzero if packet 383 * has trailing header; if_rubaget will then force this header 384 * information to be at the front, but we still have to drop 385 * the type and length which are at the front of any trailer data. 386 */ 387 m = if_rubaget(&es->es_ifuba, len, off); 388 if (m == 0) 389 goto setup; 390 if (off) { 391 m->m_off += 2 * sizeof (u_short); 392 m->m_len -= 2 * sizeof (u_short); 393 } 394 switch (en->en_type) { 395 396 #ifdef INET 397 case ENPUP_IPTYPE: 398 schednetisr(NETISR_IP); 399 inq = &ipintrq; 400 break; 401 #endif 402 #ifdef PUP 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, (struct sockaddr *)&pupsrc, 410 (struct sockaddr *)&pupdst); 411 goto setup; 412 } 413 #endif 414 default: 415 m_freem(m); 416 goto setup; 417 } 418 419 if (IF_QFULL(inq)) { 420 IF_DROP(inq); 421 m_freem(m); 422 } else 423 IF_ENQUEUE(inq, m); 424 425 setup: 426 /* 427 * Reset for next packet. 428 */ 429 addr->en_iba = es->es_ifuba.ifu_r.ifrw_info; 430 addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1; 431 addr->en_istat = EN_IEN|EN_GO; 432 } 433 434 /* 435 * Ethernet output routine. 436 * Encapsulate a packet of type family for the local net. 437 * Use trailer local net encapsulation if enough data in first 438 * packet leaves a multiple of 512 bytes of data in remainder. 439 */ 440 enoutput(ifp, m0, dst) 441 struct ifnet *ifp; 442 struct mbuf *m0; 443 struct sockaddr *dst; 444 { 445 int type, dest, s, error; 446 register struct mbuf *m = m0; 447 register struct en_header *en; 448 register int off; 449 450 switch (dst->sa_family) { 451 452 #ifdef INET 453 case AF_INET: 454 dest = ((struct sockaddr_in *)dst)->sin_addr.s_addr; 455 if (dest & 0x00ffff00) { 456 error = EPERM; /* ??? */ 457 goto bad; 458 } 459 dest = (dest >> 24) & 0xff; 460 off = ntohs((u_short)mtod(m, struct ip *)->ip_len) - m->m_len; 461 if (off > 0 && (off & 0x1ff) == 0 && 462 m->m_off >= MMINOFF + 2 * sizeof (u_short)) { 463 type = ENPUP_TRAIL + (off>>9); 464 m->m_off -= 2 * sizeof (u_short); 465 m->m_len += 2 * sizeof (u_short); 466 *mtod(m, u_short *) = ENPUP_IPTYPE; 467 *(mtod(m, u_short *) + 1) = m->m_len; 468 goto gottrailertype; 469 } 470 type = ENPUP_IPTYPE; 471 off = 0; 472 goto gottype; 473 #endif 474 #ifdef PUP 475 case AF_PUP: 476 dest = ((struct sockaddr_pup *)dst)->spup_addr.pp_host; 477 type = ENPUP_PUPTYPE; 478 off = 0; 479 goto gottype; 480 #endif 481 482 default: 483 printf("en%d: can't handle af%d\n", ifp->if_unit, 484 dst->sa_family); 485 error = EAFNOSUPPORT; 486 goto bad; 487 } 488 489 gottrailertype: 490 /* 491 * Packet to be sent as trailer: move first packet 492 * (control information) to end of chain. 493 */ 494 while (m->m_next) 495 m = m->m_next; 496 m->m_next = m0; 497 m = m0->m_next; 498 m0->m_next = 0; 499 m0 = m; 500 501 gottype: 502 /* 503 * Add local net header. If no space in first mbuf, 504 * allocate another. 505 */ 506 if (m->m_off > MMAXOFF || 507 MMINOFF + sizeof (struct en_header) > m->m_off) { 508 m = m_get(M_DONTWAIT); 509 if (m == 0) { 510 error = ENOBUFS; 511 goto bad; 512 } 513 m->m_next = m0; 514 m->m_off = MMINOFF; 515 m->m_len = sizeof (struct en_header); 516 } else { 517 m->m_off -= sizeof (struct en_header); 518 m->m_len += sizeof (struct en_header); 519 } 520 en = mtod(m, struct en_header *); 521 en->en_shost = ifp->if_host[0]; 522 en->en_dhost = dest; 523 en->en_type = type; 524 525 /* 526 * Queue message on interface, and start output if interface 527 * not yet active. 528 */ 529 s = splimp(); 530 if (IF_QFULL(&ifp->if_snd)) { 531 IF_DROP(&ifp->if_snd); 532 error = ENOBUFS; 533 goto qfull; 534 } 535 IF_ENQUEUE(&ifp->if_snd, m); 536 if (en_softc[ifp->if_unit].es_oactive == 0) 537 enstart(ifp->if_unit); 538 splx(s); 539 return (0); 540 qfull: 541 m0 = m; 542 splx(s); 543 bad: 544 m_freem(m0); 545 return (error); 546 } 547