Annotation of sys/dev/isa/if_el.c, Revision 1.1
1.1 ! nbrk 1: /* $OpenBSD: if_el.c,v 1.20 2006/03/25 22:41:44 djm Exp $ */
! 2: /* $NetBSD: if_el.c,v 1.39 1996/05/12 23:52:32 mycroft Exp $ */
! 3:
! 4: /*
! 5: * Copyright (c) 1994, Matthew E. Kimmel. Permission is hereby granted
! 6: * to use, copy, modify and distribute this software provided that both
! 7: * the copyright notice and this permission notice appear in all copies
! 8: * of the software, derivative works or modified versions, and any
! 9: * portions thereof.
! 10: */
! 11:
! 12: /*
! 13: * 3COM Etherlink 3C501 device driver
! 14: */
! 15:
! 16: /*
! 17: * Bugs/possible improvements:
! 18: * - Does not currently support DMA
! 19: * - Does not currently support multicasts
! 20: */
! 21:
! 22: #include "bpfilter.h"
! 23:
! 24: #include <sys/param.h>
! 25: #include <sys/systm.h>
! 26: #include <sys/errno.h>
! 27: #include <sys/ioctl.h>
! 28: #include <sys/mbuf.h>
! 29: #include <sys/socket.h>
! 30: #include <sys/syslog.h>
! 31: #include <sys/device.h>
! 32:
! 33: #include <net/if.h>
! 34: #include <net/if_dl.h>
! 35: #include <net/if_types.h>
! 36:
! 37: #ifdef INET
! 38: #include <netinet/in.h>
! 39: #include <netinet/in_systm.h>
! 40: #include <netinet/in_var.h>
! 41: #include <netinet/ip.h>
! 42: #include <netinet/if_ether.h>
! 43: #endif
! 44:
! 45: #if NBPFILTER > 0
! 46: #include <net/bpf.h>
! 47: #endif
! 48:
! 49: #include <machine/cpu.h>
! 50: #include <machine/intr.h>
! 51: #include <machine/pio.h>
! 52:
! 53: #include <dev/isa/isavar.h>
! 54: #include <dev/isa/if_elreg.h>
! 55:
! 56: /* for debugging convenience */
! 57: #ifdef EL_DEBUG
! 58: #define dprintf(x) printf x
! 59: #else
! 60: #define dprintf(x)
! 61: #endif
! 62:
! 63: /*
! 64: * per-line info and status
! 65: */
! 66: struct el_softc {
! 67: struct device sc_dev;
! 68: void *sc_ih;
! 69:
! 70: struct arpcom sc_arpcom; /* ethernet common */
! 71: int sc_iobase; /* base I/O addr */
! 72: };
! 73:
! 74: /*
! 75: * prototypes
! 76: */
! 77: int elintr(void *);
! 78: void elinit(struct el_softc *);
! 79: int elioctl(struct ifnet *, u_long, caddr_t);
! 80: void elstart(struct ifnet *);
! 81: void elwatchdog(struct ifnet *);
! 82: void elreset(struct el_softc *);
! 83: void elstop(struct el_softc *);
! 84: static int el_xmit(struct el_softc *);
! 85: void elread(struct el_softc *, int);
! 86: struct mbuf *elget(struct el_softc *sc, int);
! 87: static inline void el_hardreset(struct el_softc *);
! 88:
! 89: int elprobe(struct device *, void *, void *);
! 90: void elattach(struct device *, struct device *, void *);
! 91:
! 92: struct cfattach el_ca = {
! 93: sizeof(struct el_softc), elprobe, elattach
! 94: };
! 95:
! 96: struct cfdriver el_cd = {
! 97: NULL, "el", DV_IFNET
! 98: };
! 99:
! 100: /*
! 101: * Probe routine.
! 102: *
! 103: * See if the card is there and at the right place.
! 104: * (XXX - cgd -- needs help)
! 105: */
! 106: int
! 107: elprobe(parent, match, aux)
! 108: struct device *parent;
! 109: void *match, *aux;
! 110: {
! 111: struct el_softc *sc = match;
! 112: struct isa_attach_args *ia = aux;
! 113: int iobase = ia->ia_iobase;
! 114: u_char station_addr[ETHER_ADDR_LEN];
! 115: int i;
! 116:
! 117: /* First check the base. */
! 118: if (iobase < 0x280 || iobase > 0x3f0)
! 119: return 0;
! 120:
! 121: /* Grab some info for our structure. */
! 122: sc->sc_iobase = iobase;
! 123:
! 124: /*
! 125: * Now attempt to grab the station address from the PROM and see if it
! 126: * contains the 3com vendor code.
! 127: */
! 128: dprintf(("Probing 3c501 at 0x%x...\n", iobase));
! 129:
! 130: /* Reset the board. */
! 131: dprintf(("Resetting board...\n"));
! 132: outb(iobase+EL_AC, EL_AC_RESET);
! 133: delay(5);
! 134: outb(iobase+EL_AC, 0);
! 135:
! 136: /* Now read the address. */
! 137: dprintf(("Reading station address...\n"));
! 138: for (i = 0; i < ETHER_ADDR_LEN; i++) {
! 139: outb(iobase+EL_GPBL, i);
! 140: station_addr[i] = inb(iobase+EL_EAW);
! 141: }
! 142: dprintf(("Address is %s\n", ether_sprintf(station_addr)));
! 143:
! 144: /*
! 145: * If the vendor code is ok, return a 1. We'll assume that whoever
! 146: * configured this system is right about the IRQ.
! 147: */
! 148: if (station_addr[0] != 0x02 || station_addr[1] != 0x60 ||
! 149: station_addr[2] != 0x8c) {
! 150: dprintf(("Bad vendor code.\n"));
! 151: return 0;
! 152: }
! 153:
! 154: dprintf(("Vendor code ok.\n"));
! 155: /* Copy the station address into the arpcom structure. */
! 156: bcopy(station_addr, sc->sc_arpcom.ac_enaddr, ETHER_ADDR_LEN);
! 157:
! 158: ia->ia_iosize = 4; /* XXX */
! 159: ia->ia_msize = 0;
! 160: return 1;
! 161: }
! 162:
! 163: /*
! 164: * Attach the interface to the kernel data structures. By the time this is
! 165: * called, we know that the card exists at the given I/O address. We still
! 166: * assume that the IRQ given is correct.
! 167: */
! 168: void
! 169: elattach(parent, self, aux)
! 170: struct device *parent, *self;
! 171: void *aux;
! 172: {
! 173: struct el_softc *sc = (void *)self;
! 174: struct isa_attach_args *ia = aux;
! 175: struct ifnet *ifp = &sc->sc_arpcom.ac_if;
! 176:
! 177: dprintf(("Attaching %s...\n", sc->sc_dev.dv_xname));
! 178:
! 179: /* Stop the board. */
! 180: elstop(sc);
! 181:
! 182: /* Initialize ifnet structure. */
! 183: bcopy(sc->sc_dev.dv_xname, ifp->if_xname, IFNAMSIZ);
! 184: ifp->if_softc = sc;
! 185: ifp->if_start = elstart;
! 186: ifp->if_ioctl = elioctl;
! 187: ifp->if_watchdog = elwatchdog;
! 188: ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_NOTRAILERS;
! 189: IFQ_SET_READY(&ifp->if_snd);
! 190:
! 191: /* Now we can attach the interface. */
! 192: dprintf(("Attaching interface...\n"));
! 193: if_attach(ifp);
! 194: ether_ifattach(ifp);
! 195:
! 196: /* Print out some information for the user. */
! 197: printf(": address %s\n", ether_sprintf(sc->sc_arpcom.ac_enaddr));
! 198:
! 199: sc->sc_ih = isa_intr_establish(ia->ia_ic, ia->ia_irq, IST_EDGE,
! 200: IPL_NET, elintr, sc, sc->sc_dev.dv_xname);
! 201:
! 202: dprintf(("elattach() finished.\n"));
! 203: }
! 204:
! 205: /*
! 206: * Reset interface.
! 207: */
! 208: void
! 209: elreset(sc)
! 210: struct el_softc *sc;
! 211: {
! 212: int s;
! 213:
! 214: dprintf(("elreset()\n"));
! 215: s = splnet();
! 216: elstop(sc);
! 217: elinit(sc);
! 218: splx(s);
! 219: }
! 220:
! 221: /*
! 222: * Stop interface.
! 223: */
! 224: void
! 225: elstop(sc)
! 226: struct el_softc *sc;
! 227: {
! 228:
! 229: outb(sc->sc_iobase+EL_AC, 0);
! 230: }
! 231:
! 232: /*
! 233: * Do a hardware reset of the board, and upload the ethernet address again in
! 234: * case the board forgets.
! 235: */
! 236: static inline void
! 237: el_hardreset(sc)
! 238: struct el_softc *sc;
! 239: {
! 240: int iobase = sc->sc_iobase;
! 241: int i;
! 242:
! 243: outb(iobase+EL_AC, EL_AC_RESET);
! 244: delay(5);
! 245: outb(iobase+EL_AC, 0);
! 246:
! 247: for (i = 0; i < ETHER_ADDR_LEN; i++)
! 248: outb(iobase+i, sc->sc_arpcom.ac_enaddr[i]);
! 249: }
! 250:
! 251: /*
! 252: * Initialize interface.
! 253: */
! 254: void
! 255: elinit(sc)
! 256: struct el_softc *sc;
! 257: {
! 258: struct ifnet *ifp = &sc->sc_arpcom.ac_if;
! 259: int iobase = sc->sc_iobase;
! 260:
! 261: /* First, reset the board. */
! 262: el_hardreset(sc);
! 263:
! 264: /* Configure rx. */
! 265: dprintf(("Configuring rx...\n"));
! 266: if (ifp->if_flags & IFF_PROMISC)
! 267: outb(iobase+EL_RXC, EL_RXC_AGF | EL_RXC_DSHORT | EL_RXC_DDRIB | EL_RXC_DOFLOW | EL_RXC_PROMISC);
! 268: else
! 269: outb(iobase+EL_RXC, EL_RXC_AGF | EL_RXC_DSHORT | EL_RXC_DDRIB | EL_RXC_DOFLOW | EL_RXC_ABROAD);
! 270: outb(iobase+EL_RBC, 0);
! 271:
! 272: /* Configure TX. */
! 273: dprintf(("Configuring tx...\n"));
! 274: outb(iobase+EL_TXC, 0);
! 275:
! 276: /* Start reception. */
! 277: dprintf(("Starting reception...\n"));
! 278: outb(iobase+EL_AC, EL_AC_IRQE | EL_AC_RX);
! 279:
! 280: /* Set flags appropriately. */
! 281: ifp->if_flags |= IFF_RUNNING;
! 282: ifp->if_flags &= ~IFF_OACTIVE;
! 283:
! 284: /* And start output. */
! 285: elstart(ifp);
! 286: }
! 287:
! 288: /*
! 289: * Start output on interface. Get datagrams from the queue and output them,
! 290: * giving the receiver a chance between datagrams. Call only from splnet or
! 291: * interrupt level!
! 292: */
! 293: void
! 294: elstart(ifp)
! 295: struct ifnet *ifp;
! 296: {
! 297: struct el_softc *sc = ifp->if_softc;
! 298: int iobase = sc->sc_iobase;
! 299: struct mbuf *m, *m0;
! 300: int s, i, off, retries;
! 301:
! 302: dprintf(("elstart()...\n"));
! 303: s = splnet();
! 304:
! 305: /* Don't do anything if output is active. */
! 306: if ((ifp->if_flags & IFF_OACTIVE) != 0) {
! 307: splx(s);
! 308: return;
! 309: }
! 310:
! 311: ifp->if_flags |= IFF_OACTIVE;
! 312:
! 313: /*
! 314: * The main loop. They warned me against endless loops, but would I
! 315: * listen? NOOO....
! 316: */
! 317: for (;;) {
! 318: /* Dequeue the next datagram. */
! 319: IFQ_DEQUEUE(&ifp->if_snd, m0);
! 320:
! 321: /* If there's nothing to send, return. */
! 322: if (m0 == 0)
! 323: break;
! 324:
! 325: #if NBPFILTER > 0
! 326: /* Give the packet to the bpf, if any. */
! 327: if (ifp->if_bpf)
! 328: bpf_mtap(ifp->if_bpf, m0, BPF_DIRECTION_OUT);
! 329: #endif
! 330:
! 331: /* Disable the receiver. */
! 332: outb(iobase+EL_AC, EL_AC_HOST);
! 333: outb(iobase+EL_RBC, 0);
! 334:
! 335: /* Transfer datagram to board. */
! 336: dprintf(("el: xfr pkt length=%d...\n", m0->m_pkthdr.len));
! 337: off = EL_BUFSIZ - max(m0->m_pkthdr.len, ETHER_MIN_LEN);
! 338: outb(iobase+EL_GPBL, off);
! 339: outb(iobase+EL_GPBH, off >> 8);
! 340:
! 341: /* Copy the datagram to the buffer. */
! 342: for (m = m0; m != 0; m = m->m_next)
! 343: outsb(iobase+EL_BUF, mtod(m, caddr_t), m->m_len);
! 344: for (i = 0;
! 345: i < ETHER_MIN_LEN - ETHER_CRC_LEN - m0->m_pkthdr.len; i++)
! 346: outb(iobase+EL_BUF, 0);
! 347:
! 348: m_freem(m0);
! 349:
! 350: /* Now transmit the datagram. */
! 351: retries = 0;
! 352: for (;;) {
! 353: outb(iobase+EL_GPBL, off);
! 354: outb(iobase+EL_GPBH, off >> 8);
! 355: if (el_xmit(sc)) {
! 356: ifp->if_oerrors++;
! 357: break;
! 358: }
! 359: /* Check out status. */
! 360: i = inb(iobase+EL_TXS);
! 361: dprintf(("tx status=0x%x\n", i));
! 362: if ((i & EL_TXS_READY) == 0) {
! 363: dprintf(("el: err txs=%x\n", i));
! 364: if (i & (EL_TXS_COLL | EL_TXS_COLL16)) {
! 365: ifp->if_collisions++;
! 366: if ((i & EL_TXC_DCOLL16) == 0 &&
! 367: retries < 15) {
! 368: retries++;
! 369: outb(iobase+EL_AC, EL_AC_HOST);
! 370: }
! 371: } else {
! 372: ifp->if_oerrors++;
! 373: break;
! 374: }
! 375: } else {
! 376: ifp->if_opackets++;
! 377: break;
! 378: }
! 379: }
! 380:
! 381: /*
! 382: * Now give the card a chance to receive.
! 383: * Gotta love 3c501s...
! 384: */
! 385: (void)inb(iobase+EL_AS);
! 386: outb(iobase+EL_AC, EL_AC_IRQE | EL_AC_RX);
! 387: splx(s);
! 388: /* Interrupt here. */
! 389: s = splnet();
! 390: }
! 391:
! 392: (void)inb(iobase+EL_AS);
! 393: outb(iobase+EL_AC, EL_AC_IRQE | EL_AC_RX);
! 394: ifp->if_flags &= ~IFF_OACTIVE;
! 395: splx(s);
! 396: }
! 397:
! 398: /*
! 399: * This function actually attempts to transmit a datagram downloaded to the
! 400: * board. Call at splnet or interrupt, after downloading data! Returns 0 on
! 401: * success, non-0 on failure.
! 402: */
! 403: static int
! 404: el_xmit(sc)
! 405: struct el_softc *sc;
! 406: {
! 407: int iobase = sc->sc_iobase;
! 408: int i;
! 409:
! 410: /*
! 411: * XXX
! 412: * This busy-waits for the tx completion. Can we get an interrupt
! 413: * instead?
! 414: */
! 415:
! 416: dprintf(("el: xmit..."));
! 417: outb(iobase+EL_AC, EL_AC_TXFRX);
! 418: i = 20000;
! 419: while ((inb(iobase+EL_AS) & EL_AS_TXBUSY) && (i > 0))
! 420: i--;
! 421: if (i == 0) {
! 422: dprintf(("tx not ready\n"));
! 423: return -1;
! 424: }
! 425: dprintf(("%d cycles.\n", 20000 - i));
! 426: return 0;
! 427: }
! 428:
! 429: /*
! 430: * Controller interrupt.
! 431: */
! 432: int
! 433: elintr(arg)
! 434: void *arg;
! 435: {
! 436: register struct el_softc *sc = arg;
! 437: int iobase = sc->sc_iobase;
! 438: int rxstat, len;
! 439:
! 440: dprintf(("elintr: "));
! 441:
! 442: /* Check board status. */
! 443: if ((inb(iobase+EL_AS) & EL_AS_RXBUSY) != 0) {
! 444: (void)inb(iobase+EL_RXC);
! 445: outb(iobase+EL_AC, EL_AC_IRQE | EL_AC_RX);
! 446: return 0;
! 447: }
! 448:
! 449: for (;;) {
! 450: rxstat = inb(iobase+EL_RXS);
! 451: if (rxstat & EL_RXS_STALE)
! 452: break;
! 453:
! 454: /* If there's an overflow, reinit the board. */
! 455: if ((rxstat & EL_RXS_NOFLOW) == 0) {
! 456: dprintf(("overflow.\n"));
! 457: el_hardreset(sc);
! 458: /* Put board back into receive mode. */
! 459: if (sc->sc_arpcom.ac_if.if_flags & IFF_PROMISC)
! 460: outb(iobase+EL_RXC, EL_RXC_AGF | EL_RXC_DSHORT | EL_RXC_DDRIB | EL_RXC_DOFLOW | EL_RXC_PROMISC);
! 461: else
! 462: outb(iobase+EL_RXC, EL_RXC_AGF | EL_RXC_DSHORT | EL_RXC_DDRIB | EL_RXC_DOFLOW | EL_RXC_ABROAD);
! 463: (void)inb(iobase+EL_AS);
! 464: outb(iobase+EL_RBC, 0);
! 465: break;
! 466: }
! 467:
! 468: /* Incoming packet. */
! 469: len = inb(iobase+EL_RBL);
! 470: len |= inb(iobase+EL_RBH) << 8;
! 471: dprintf(("receive len=%d rxstat=%x ", len, rxstat));
! 472: outb(iobase+EL_AC, EL_AC_HOST);
! 473:
! 474: /* Pass data up to upper levels. */
! 475: elread(sc, len);
! 476:
! 477: /* Is there another packet? */
! 478: if ((inb(iobase+EL_AS) & EL_AS_RXBUSY) != 0)
! 479: break;
! 480:
! 481: dprintf(("<rescan> "));
! 482: }
! 483:
! 484: (void)inb(iobase+EL_RXC);
! 485: outb(iobase+EL_AC, EL_AC_IRQE | EL_AC_RX);
! 486: return 1;
! 487: }
! 488:
! 489: /*
! 490: * Pass a packet to the higher levels.
! 491: */
! 492: void
! 493: elread(sc, len)
! 494: register struct el_softc *sc;
! 495: int len;
! 496: {
! 497: struct ifnet *ifp = &sc->sc_arpcom.ac_if;
! 498: struct mbuf *m;
! 499:
! 500: if (len <= sizeof(struct ether_header) ||
! 501: len > ETHER_MAX_LEN) {
! 502: printf("%s: invalid packet size %d; dropping\n",
! 503: sc->sc_dev.dv_xname, len);
! 504: ifp->if_ierrors++;
! 505: return;
! 506: }
! 507:
! 508: /* Pull packet off interface. */
! 509: m = elget(sc, len);
! 510: if (m == 0) {
! 511: ifp->if_ierrors++;
! 512: return;
! 513: }
! 514:
! 515: ifp->if_ipackets++;
! 516:
! 517: #if NBPFILTER > 0
! 518: /*
! 519: * Check if there's a BPF listener on this interface.
! 520: * If so, hand off the raw packet to BPF.
! 521: */
! 522: if (ifp->if_bpf)
! 523: bpf_mtap(ifp->if_bpf, m, BPF_DIRECTION_IN);
! 524: #endif
! 525:
! 526: ether_input_mbuf(ifp, m);
! 527: }
! 528:
! 529: /*
! 530: * Pull read data off a interface. Len is length of data, with local net
! 531: * header stripped. We copy the data into mbufs. When full cluster sized
! 532: * units are present we copy into clusters.
! 533: */
! 534: struct mbuf *
! 535: elget(sc, totlen)
! 536: struct el_softc *sc;
! 537: int totlen;
! 538: {
! 539: struct ifnet *ifp = &sc->sc_arpcom.ac_if;
! 540: int iobase = sc->sc_iobase;
! 541: struct mbuf *top, **mp, *m;
! 542: int len;
! 543:
! 544: MGETHDR(m, M_DONTWAIT, MT_DATA);
! 545: if (m == 0)
! 546: return 0;
! 547: m->m_pkthdr.rcvif = ifp;
! 548: m->m_pkthdr.len = totlen;
! 549: len = MHLEN;
! 550: top = 0;
! 551: mp = ⊤
! 552:
! 553: outb(iobase+EL_GPBL, 0);
! 554: outb(iobase+EL_GPBH, 0);
! 555:
! 556: while (totlen > 0) {
! 557: if (top) {
! 558: MGET(m, M_DONTWAIT, MT_DATA);
! 559: if (m == 0) {
! 560: m_freem(top);
! 561: return 0;
! 562: }
! 563: len = MLEN;
! 564: }
! 565: if (totlen >= MINCLSIZE) {
! 566: MCLGET(m, M_DONTWAIT);
! 567: if (m->m_flags & M_EXT)
! 568: len = MCLBYTES;
! 569: }
! 570: m->m_len = len = min(totlen, len);
! 571: insb(iobase+EL_BUF, mtod(m, caddr_t), len);
! 572: totlen -= len;
! 573: *mp = m;
! 574: mp = &m->m_next;
! 575: }
! 576:
! 577: outb(iobase+EL_RBC, 0);
! 578: outb(iobase+EL_AC, EL_AC_RX);
! 579:
! 580: return top;
! 581: }
! 582:
! 583: /*
! 584: * Process an ioctl request. This code needs some work - it looks pretty ugly.
! 585: */
! 586: int
! 587: elioctl(ifp, cmd, data)
! 588: register struct ifnet *ifp;
! 589: u_long cmd;
! 590: caddr_t data;
! 591: {
! 592: struct el_softc *sc = ifp->if_softc;
! 593: struct ifaddr *ifa = (struct ifaddr *)data;
! 594: int s, error = 0;
! 595:
! 596: s = splnet();
! 597:
! 598: if ((error = ether_ioctl(ifp, &sc->sc_arpcom, cmd, data)) > 0) {
! 599: splx(s);
! 600: return error;
! 601: }
! 602:
! 603: switch (cmd) {
! 604:
! 605: case SIOCSIFADDR:
! 606: ifp->if_flags |= IFF_UP;
! 607:
! 608: switch (ifa->ifa_addr->sa_family) {
! 609: #ifdef INET
! 610: case AF_INET:
! 611: elinit(sc);
! 612: arp_ifinit(&sc->sc_arpcom, ifa);
! 613: break;
! 614: #endif
! 615: default:
! 616: elinit(sc);
! 617: break;
! 618: }
! 619: break;
! 620:
! 621: case SIOCSIFFLAGS:
! 622: if ((ifp->if_flags & IFF_UP) == 0 &&
! 623: (ifp->if_flags & IFF_RUNNING) != 0) {
! 624: /*
! 625: * If interface is marked down and it is running, then
! 626: * stop it.
! 627: */
! 628: elstop(sc);
! 629: ifp->if_flags &= ~IFF_RUNNING;
! 630: } else if ((ifp->if_flags & IFF_UP) != 0 &&
! 631: (ifp->if_flags & IFF_RUNNING) == 0) {
! 632: /*
! 633: * If interface is marked up and it is stopped, then
! 634: * start it.
! 635: */
! 636: elinit(sc);
! 637: } else {
! 638: /*
! 639: * Some other important flag might have changed, so
! 640: * reset.
! 641: */
! 642: elreset(sc);
! 643: }
! 644: break;
! 645:
! 646: default:
! 647: error = EINVAL;
! 648: break;
! 649: }
! 650:
! 651: splx(s);
! 652: return error;
! 653: }
! 654:
! 655: /*
! 656: * Device timeout routine.
! 657: */
! 658: void
! 659: elwatchdog(ifp)
! 660: struct ifnet *ifp;
! 661: {
! 662: struct el_softc *sc = ifp->if_softc;
! 663:
! 664: log(LOG_ERR, "%s: device timeout\n", sc->sc_dev.dv_xname);
! 665: sc->sc_arpcom.ac_if.if_oerrors++;
! 666:
! 667: elreset(sc);
! 668: }
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