xref: /netbsd-src/sys/arch/macppc/dev/am79c950.c (revision f3b496ec9be495acbb17756f05d342b6b7b495e9)
1 /*	$NetBSD: am79c950.c,v 1.18 2006/09/07 02:40:31 dogcow Exp $	*/
2 
3 /*-
4  * Copyright (c) 1997 David Huang <khym@bga.com>
5  * All rights reserved.
6  *
7  * Portions of this code are based on code by Denton Gentry <denny1@home.com>,
8  * Charles M. Hannum, Yanagisawa Takeshi <yanagisw@aa.ap.titech.ac.jp>, and
9  * Jason R. Thorpe.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. The name of the author may not be used to endorse or promote products
17  *    derived from this software without specific prior written permission
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  *
30  */
31 
32 /*
33  * Driver for the AMD Am79C940 (MACE) ethernet chip, used for onboard
34  * ethernet on the Centris/Quadra 660av and Quadra 840av.
35  */
36 
37 #include <sys/cdefs.h>
38 __KERNEL_RCSID(0, "$NetBSD: am79c950.c,v 1.18 2006/09/07 02:40:31 dogcow Exp $");
39 
40 #include "opt_inet.h"
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/mbuf.h>
45 #include <sys/buf.h>
46 #include <sys/protosw.h>
47 #include <sys/socket.h>
48 #include <sys/syslog.h>
49 #include <sys/ioctl.h>
50 #include <sys/errno.h>
51 #include <sys/device.h>
52 
53 #include <uvm/uvm_extern.h>
54 
55 #include <net/if.h>
56 #include <net/if_dl.h>
57 #include <net/if_ether.h>
58 #include <net/if_media.h>
59 
60 #ifdef INET
61 #include <netinet/in.h>
62 #include <netinet/if_inarp.h>
63 #include <netinet/in_systm.h>
64 #include <netinet/in_var.h>
65 #include <netinet/ip.h>
66 #endif
67 
68 
69 
70 #include <uvm/uvm_extern.h>
71 
72 #include "bpfilter.h"
73 #if NBPFILTER > 0
74 #include <net/bpf.h>
75 #include <net/bpfdesc.h>
76 #endif
77 
78 #include <machine/pio.h>
79 #include <machine/bus.h>
80 
81 #include <macppc/dev/am79c950reg.h>
82 #include <macppc/dev/if_mcvar.h>
83 
84 hide void	mcwatchdog __P((struct ifnet *));
85 hide int	mcinit __P((struct mc_softc *sc));
86 hide int	mcstop __P((struct mc_softc *sc));
87 hide int	mcioctl __P((struct ifnet *ifp, u_long cmd, caddr_t data));
88 hide void	mcstart __P((struct ifnet *ifp));
89 hide void	mcreset __P((struct mc_softc *sc));
90 
91 integrate u_int	maceput __P((struct mc_softc *sc, struct mbuf *m0));
92 integrate void	mc_tint __P((struct mc_softc *sc));
93 integrate void	mace_read __P((struct mc_softc *, caddr_t, int));
94 integrate struct mbuf *mace_get __P((struct mc_softc *, caddr_t, int));
95 static void mace_calcladrf __P((struct ethercom *ac, u_int8_t *af));
96 static inline u_int16_t ether_cmp __P((void *, void *));
97 static int mc_mediachange __P((struct ifnet *));
98 static void mc_mediastatus __P((struct ifnet *, struct ifmediareq *));
99 
100 /*
101  * Compare two Ether/802 addresses for equality, inlined and
102  * unrolled for speed.  Use this like memcmp().
103  *
104  * XXX: Add <machine/inlines.h> for stuff like this?
105  * XXX: or maybe add it to libkern.h instead?
106  *
107  * "I'd love to have an inline assembler version of this."
108  * XXX: Who wanted that? mycroft?  I wrote one, but this
109  * version in C is as good as hand-coded assembly. -gwr
110  *
111  * Please do NOT tweak this without looking at the actual
112  * assembly code generated before and after your tweaks!
113  */
114 static inline u_int16_t
115 ether_cmp(one, two)
116 	void *one, *two;
117 {
118 	register u_int16_t *a = (u_short *) one;
119 	register u_int16_t *b = (u_short *) two;
120 	register u_int16_t diff;
121 
122 #ifdef	m68k
123 	/*
124 	 * The post-increment-pointer form produces the best
125 	 * machine code for m68k.  This was carefully tuned
126 	 * so it compiles to just 8 short (2-byte) op-codes!
127 	 */
128 	diff  = *a++ - *b++;
129 	diff |= *a++ - *b++;
130 	diff |= *a++ - *b++;
131 #else
132 	/*
133 	 * Most modern CPUs do better with a single expresion.
134 	 * Note that short-cut evaluation is NOT helpful here,
135 	 * because it just makes the code longer, not faster!
136 	 */
137 	diff = (a[0] - b[0]) | (a[1] - b[1]) | (a[2] - b[2]);
138 #endif
139 
140 	return (diff);
141 }
142 
143 #define ETHER_CMP	ether_cmp
144 
145 /*
146  * Interface exists: make available by filling in network interface
147  * record.  System will initialize the interface when it is ready
148  * to accept packets.
149  */
150 int
151 mcsetup(sc, lladdr)
152 	struct mc_softc	*sc;
153 	u_int8_t *lladdr;
154 {
155 	struct ifnet *ifp = &sc->sc_if;
156 
157 	/* reset the chip and disable all interrupts */
158 	NIC_PUT(sc, MACE_BIUCC, SWRST);
159 	DELAY(100);
160 	NIC_PUT(sc, MACE_IMR, ~0);
161 
162 	memcpy(sc->sc_enaddr, lladdr, ETHER_ADDR_LEN);
163 	printf(": address %s\n", ether_sprintf(lladdr));
164 
165 	memcpy(ifp->if_xname, sc->sc_dev.dv_xname, IFNAMSIZ);
166 	ifp->if_softc = sc;
167 	ifp->if_ioctl = mcioctl;
168 	ifp->if_start = mcstart;
169 	ifp->if_flags =
170 	    IFF_BROADCAST | IFF_SIMPLEX | IFF_NOTRAILERS | IFF_MULTICAST;
171 	ifp->if_watchdog = mcwatchdog;
172 
173 	/* initialize ifmedia structures */
174 	ifmedia_init(&sc->sc_media, 0, mc_mediachange, mc_mediastatus);
175 	ifmedia_add(&sc->sc_media, IFM_ETHER|IFM_MANUAL, 0, NULL);
176 	ifmedia_set(&sc->sc_media, IFM_ETHER|IFM_MANUAL);
177 
178 	if_attach(ifp);
179 	ether_ifattach(ifp, lladdr);
180 
181 	return (0);
182 }
183 
184 hide int
185 mcioctl(ifp, cmd, data)
186 	struct ifnet *ifp;
187 	u_long cmd;
188 	caddr_t data;
189 {
190 	struct mc_softc *sc = ifp->if_softc;
191 	struct ifaddr *ifa;
192 	struct ifreq *ifr;
193 
194 	int	s = splnet(), err = 0;
195 
196 	switch (cmd) {
197 
198 	case SIOCSIFADDR:
199 		ifa = (struct ifaddr *)data;
200 		ifp->if_flags |= IFF_UP;
201 		switch (ifa->ifa_addr->sa_family) {
202 #ifdef INET
203 		case AF_INET:
204 			mcinit(sc);
205 			arp_ifinit(ifp, ifa);
206 			break;
207 #endif
208 		default:
209 			mcinit(sc);
210 			break;
211 		}
212 		break;
213 
214 	case SIOCSIFFLAGS:
215 		if ((ifp->if_flags & IFF_UP) == 0 &&
216 		    (ifp->if_flags & IFF_RUNNING) != 0) {
217 			/*
218 			 * If interface is marked down and it is running,
219 			 * then stop it.
220 			 */
221 			mcstop(sc);
222 			ifp->if_flags &= ~IFF_RUNNING;
223 		} else if ((ifp->if_flags & IFF_UP) != 0 &&
224 		    (ifp->if_flags & IFF_RUNNING) == 0) {
225 			/*
226 			 * If interface is marked up and it is stopped,
227 			 * then start it.
228 			 */
229 			(void)mcinit(sc);
230 		} else {
231 			/*
232 			 * reset the interface to pick up any other changes
233 			 * in flags
234 			 */
235 			mcreset(sc);
236 			mcstart(ifp);
237 		}
238 		break;
239 
240 	case SIOCADDMULTI:
241 	case SIOCDELMULTI:
242 		ifr = (struct ifreq *) data;
243 		err = (cmd == SIOCADDMULTI) ?
244 		    ether_addmulti(ifr, &sc->sc_ethercom) :
245 		    ether_delmulti(ifr, &sc->sc_ethercom);
246 
247 		if (err == ENETRESET) {
248 			/*
249 			 * Multicast list has changed; set the hardware
250 			 * filter accordingly. But remember UP flag!
251 			 */
252 			if (ifp->if_flags & IFF_RUNNING)
253 				mcreset(sc);
254 			err = 0;
255 		}
256 		break;
257 
258 	case SIOCGIFMEDIA:
259 	case SIOCSIFMEDIA:
260 		ifr = (struct ifreq *) data;
261 		err = ifmedia_ioctl(ifp, ifr, &sc->sc_media, cmd);
262 		break;
263 
264 	default:
265 		err = EINVAL;
266 	}
267 	splx(s);
268 	return (err);
269 }
270 
271 /*
272  * Encapsulate a packet of type family for the local net.
273  */
274 hide void
275 mcstart(ifp)
276 	struct ifnet *ifp;
277 {
278 	struct mc_softc	*sc = ifp->if_softc;
279 	struct mbuf	*m;
280 
281 	if ((ifp->if_flags & (IFF_RUNNING | IFF_OACTIVE)) != IFF_RUNNING)
282 		return;
283 
284 	while (1) {
285 		if (ifp->if_flags & IFF_OACTIVE)
286 			return;
287 
288 		IF_DEQUEUE(&ifp->if_snd, m);
289 		if (m == 0)
290 			return;
291 
292 #if NBPFILTER > 0
293 		/*
294 		 * If bpf is listening on this interface, let it
295 		 * see the packet before we commit it to the wire.
296 		 */
297 		if (ifp->if_bpf)
298 			bpf_mtap(ifp->if_bpf, m);
299 #endif
300 
301 		/*
302 		 * Copy the mbuf chain into the transmit buffer.
303 		 */
304 		ifp->if_flags |= IFF_OACTIVE;
305 		maceput(sc, m);
306 
307 		ifp->if_opackets++;		/* # of pkts */
308 	}
309 }
310 
311 /*
312  * reset and restart the MACE.  Called in case of fatal
313  * hardware/software errors.
314  */
315 hide void
316 mcreset(sc)
317 	struct mc_softc *sc;
318 {
319 	mcstop(sc);
320 	mcinit(sc);
321 }
322 
323 hide int
324 mcinit(sc)
325 	struct mc_softc *sc;
326 {
327 	int s;
328 	u_int8_t maccc, ladrf[8];
329 
330 	if (sc->sc_if.if_flags & IFF_RUNNING)
331 		/* already running */
332 		return (0);
333 
334 	s = splnet();
335 
336 	NIC_PUT(sc, MACE_BIUCC, sc->sc_biucc);
337 	NIC_PUT(sc, MACE_FIFOCC, sc->sc_fifocc);
338 	NIC_PUT(sc, MACE_IMR, ~0); /* disable all interrupts */
339 	NIC_PUT(sc, MACE_PLSCC, sc->sc_plscc);
340 
341 	NIC_PUT(sc, MACE_UTR, RTRD); /* disable reserved test registers */
342 
343 	/* set MAC address */
344 	NIC_PUT(sc, MACE_IAC, ADDRCHG);
345 	while (NIC_GET(sc, MACE_IAC) & ADDRCHG)
346 		;
347 	NIC_PUT(sc, MACE_IAC, PHYADDR);
348 	bus_space_write_multi_1(sc->sc_regt, sc->sc_regh, MACE_REG(MACE_PADR),
349 	    sc->sc_enaddr, ETHER_ADDR_LEN);
350 
351 	/* set logical address filter */
352 	mace_calcladrf(&sc->sc_ethercom, ladrf);
353 
354 	NIC_PUT(sc, MACE_IAC, ADDRCHG);
355 	while (NIC_GET(sc, MACE_IAC) & ADDRCHG)
356 		;
357 	NIC_PUT(sc, MACE_IAC, LOGADDR);
358 	bus_space_write_multi_1(sc->sc_regt, sc->sc_regh, MACE_REG(MACE_LADRF),
359 	    ladrf, 8);
360 
361 	NIC_PUT(sc, MACE_XMTFC, APADXMT);
362 	/*
363 	 * No need to autostrip padding on receive... Ethernet frames
364 	 * don't have a length field, unlike 802.3 frames, so the MACE
365 	 * can't figure out the length of the packet anyways.
366 	 */
367 	NIC_PUT(sc, MACE_RCVFC, 0);
368 
369 	maccc = ENXMT | ENRCV;
370 	if (sc->sc_if.if_flags & IFF_PROMISC)
371 		maccc |= PROM;
372 
373 	NIC_PUT(sc, MACE_MACCC, maccc);
374 
375 	if (sc->sc_bus_init)
376 		(*sc->sc_bus_init)(sc);
377 
378 	/*
379 	 * Enable all interrupts except receive, since we use the DMA
380 	 * completion interrupt for that.
381 	 */
382 	NIC_PUT(sc, MACE_IMR, RCVINTM);
383 
384 	/* flag interface as "running" */
385 	sc->sc_if.if_flags |= IFF_RUNNING;
386 	sc->sc_if.if_flags &= ~IFF_OACTIVE;
387 
388 	splx(s);
389 	return (0);
390 }
391 
392 /*
393  * close down an interface and free its buffers
394  * Called on final close of device, or if mcinit() fails
395  * part way through.
396  */
397 hide int
398 mcstop(sc)
399 	struct mc_softc *sc;
400 {
401 	int	s = splnet();
402 
403 	NIC_PUT(sc, MACE_BIUCC, SWRST);
404 	DELAY(100);
405 
406 	sc->sc_if.if_timer = 0;
407 	sc->sc_if.if_flags &= ~IFF_RUNNING;
408 
409 	splx(s);
410 	return (0);
411 }
412 
413 /*
414  * Called if any Tx packets remain unsent after 5 seconds,
415  * In all cases we just reset the chip, and any retransmission
416  * will be handled by higher level protocol timeouts.
417  */
418 hide void
419 mcwatchdog(ifp)
420 	struct ifnet *ifp;
421 {
422 	struct mc_softc *sc = ifp->if_softc;
423 
424 	printf("mcwatchdog: resetting chip\n");
425 	mcreset(sc);
426 }
427 
428 /*
429  * stuff packet into MACE (at splnet)
430  */
431 integrate u_int
432 maceput(sc, m)
433 	struct mc_softc *sc;
434 	struct mbuf *m;
435 {
436 	struct mbuf *n;
437 	u_int len, totlen = 0;
438 	u_char *buff;
439 
440 	buff = sc->sc_txbuf;
441 
442 	for (; m; m = n) {
443 		u_char *data = mtod(m, u_char *);
444 		len = m->m_len;
445 		totlen += len;
446 		memcpy(buff, data, len);
447 		buff += len;
448 		MFREE(m, n);
449 	}
450 
451 	if (totlen > PAGE_SIZE)
452 		panic("%s: maceput: packet overflow", sc->sc_dev.dv_xname);
453 
454 #if 0
455 	if (totlen < ETHERMIN + sizeof(struct ether_header)) {
456 		int pad = ETHERMIN + sizeof(struct ether_header) - totlen;
457 		memset(sc->sc_txbuf + totlen, 0, pad);
458 		totlen = ETHERMIN + sizeof(struct ether_header);
459 	}
460 #endif
461 
462 	(*sc->sc_putpacket)(sc, totlen);
463 
464 	sc->sc_if.if_timer = 5;	/* 5 seconds to watch for failing to transmit */
465 	return (totlen);
466 }
467 
468 int
469 mcintr(arg)
470 	void *arg;
471 {
472 	struct mc_softc *sc = arg;
473 	u_int8_t ir;
474 
475 	ir = NIC_GET(sc, MACE_IR) & ~NIC_GET(sc, MACE_IMR);
476 	if (ir == 0)
477 		return 0;
478 
479 	if (ir & JAB) {
480 #ifdef MCDEBUG
481 		printf("%s: jabber error\n", sc->sc_dev.dv_xname);
482 #endif
483 		sc->sc_if.if_oerrors++;
484 	}
485 
486 	if (ir & BABL) {
487 #ifdef MCDEBUG
488 		printf("%s: babble\n", sc->sc_dev.dv_xname);
489 #endif
490 		sc->sc_if.if_oerrors++;
491 	}
492 
493 	if (ir & CERR) {
494 		printf("%s: collision error\n", sc->sc_dev.dv_xname);
495 		sc->sc_if.if_collisions++;
496 	}
497 
498 	/*
499 	 * Pretend we have carrier; if we don't this will be cleared
500 	 * shortly.
501 	 */
502 	sc->sc_havecarrier = 1;
503 
504 	if (ir & XMTINT)
505 		mc_tint(sc);
506 
507 	if (ir & RCVINT)
508 		mc_rint(sc);
509 
510 	return 1;
511 }
512 
513 integrate void
514 mc_tint(sc)
515 	struct mc_softc *sc;
516 {
517 	u_int8_t xmtrc, xmtfs;
518 
519 	xmtrc = NIC_GET(sc, MACE_XMTRC);
520 	xmtfs = NIC_GET(sc, MACE_XMTFS);
521 
522 	if ((xmtfs & XMTSV) == 0)
523 		return;
524 
525 	if (xmtfs & UFLO) {
526 		printf("%s: underflow\n", sc->sc_dev.dv_xname);
527 		mcreset(sc);
528 		return;
529 	}
530 
531 	if (xmtfs & LCOL) {
532 		printf("%s: late collision\n", sc->sc_dev.dv_xname);
533 		sc->sc_if.if_oerrors++;
534 		sc->sc_if.if_collisions++;
535 	}
536 
537 	if (xmtfs & MORE)
538 		/* Real number is unknown. */
539 		sc->sc_if.if_collisions += 2;
540 	else if (xmtfs & ONE)
541 		sc->sc_if.if_collisions++;
542 	else if (xmtfs & RTRY) {
543 		sc->sc_if.if_collisions += 16;
544 		sc->sc_if.if_oerrors++;
545 	}
546 
547 	if (xmtfs & LCAR) {
548 		sc->sc_havecarrier = 0;
549 		printf("%s: lost carrier\n", sc->sc_dev.dv_xname);
550 		sc->sc_if.if_oerrors++;
551 	}
552 
553 	sc->sc_if.if_flags &= ~IFF_OACTIVE;
554 	sc->sc_if.if_timer = 0;
555 	mcstart(&sc->sc_if);
556 }
557 
558 void
559 mc_rint(sc)
560 	struct mc_softc *sc;
561 {
562 #define	rxf	sc->sc_rxframe
563 	u_int len;
564 
565 	len = (rxf.rx_rcvcnt | ((rxf.rx_rcvsts & 0xf) << 8)) - 4;
566 
567 #ifdef MCDEBUG
568 	if (rxf.rx_rcvsts & 0xf0)
569 		printf("%s: rcvcnt %02x rcvsts %02x rntpc 0x%02x rcvcc 0x%02x\n",
570 		    sc->sc_dev.dv_xname, rxf.rx_rcvcnt, rxf.rx_rcvsts,
571 		    rxf.rx_rntpc, rxf.rx_rcvcc);
572 #endif
573 
574 	if (rxf.rx_rcvsts & OFLO) {
575 		printf("%s: receive FIFO overflow\n", sc->sc_dev.dv_xname);
576 		sc->sc_if.if_ierrors++;
577 		return;
578 	}
579 
580 	if (rxf.rx_rcvsts & CLSN)
581 		sc->sc_if.if_collisions++;
582 
583 	if (rxf.rx_rcvsts & FRAM) {
584 #ifdef MCDEBUG
585 		printf("%s: framing error\n", sc->sc_dev.dv_xname);
586 #endif
587 		sc->sc_if.if_ierrors++;
588 		return;
589 	}
590 
591 	if (rxf.rx_rcvsts & FCS) {
592 #ifdef MCDEBUG
593 		printf("%s: frame control checksum error\n", sc->sc_dev.dv_xname);
594 #endif
595 		sc->sc_if.if_ierrors++;
596 		return;
597 	}
598 
599 	mace_read(sc, rxf.rx_frame, len);
600 #undef	rxf
601 }
602 
603 integrate void
604 mace_read(sc, pkt, len)
605 	struct mc_softc *sc;
606 	caddr_t pkt;
607 	int len;
608 {
609 	struct ifnet *ifp = &sc->sc_if;
610 	struct mbuf *m;
611 
612 	if (len <= sizeof(struct ether_header) ||
613 	    len > ETHERMTU + sizeof(struct ether_header)) {
614 #ifdef MCDEBUG
615 		printf("%s: invalid packet size %d; dropping\n",
616 		    sc->sc_dev.dv_xname, len);
617 #endif
618 		ifp->if_ierrors++;
619 		return;
620 	}
621 
622 	m = mace_get(sc, pkt, len);
623 	if (m == NULL) {
624 		ifp->if_ierrors++;
625 		return;
626 	}
627 
628 	ifp->if_ipackets++;
629 
630 #if NBPFILTER > 0
631 	/* Pass this up to any BPF listeners. */
632 	if (ifp->if_bpf)
633 		bpf_mtap(ifp->if_bpf, m);
634 #endif
635 
636 	/* Pass the packet up. */
637 	(*ifp->if_input)(ifp, m);
638 }
639 
640 /*
641  * Pull data off an interface.
642  * Len is length of data, with local net header stripped.
643  * We copy the data into mbufs.  When full cluster sized units are present
644  * we copy into clusters.
645  */
646 integrate struct mbuf *
647 mace_get(sc, pkt, totlen)
648 	struct mc_softc *sc;
649 	caddr_t pkt;
650 	int totlen;
651 {
652 	register struct mbuf *m;
653 	struct mbuf *top, **mp;
654 	int len;
655 
656 	MGETHDR(m, M_DONTWAIT, MT_DATA);
657 	if (m == 0)
658 		return (0);
659 	m->m_pkthdr.rcvif = &sc->sc_if;
660 	m->m_pkthdr.len = totlen;
661 	len = MHLEN;
662 	top = 0;
663 	mp = &top;
664 
665 	while (totlen > 0) {
666 		if (top) {
667 			MGET(m, M_DONTWAIT, MT_DATA);
668 			if (m == 0) {
669 				m_freem(top);
670 				return 0;
671 			}
672 			len = MLEN;
673 		}
674 		if (totlen >= MINCLSIZE) {
675 			MCLGET(m, M_DONTWAIT);
676 			if ((m->m_flags & M_EXT) == 0) {
677 				m_free(m);
678 				m_freem(top);
679 				return 0;
680 			}
681 			len = MCLBYTES;
682 		}
683 		m->m_len = len = min(totlen, len);
684 		memcpy(mtod(m, caddr_t), pkt, len);
685 		pkt += len;
686 		totlen -= len;
687 		*mp = m;
688 		mp = &m->m_next;
689 	}
690 
691 	return (top);
692 }
693 
694 /*
695  * Go through the list of multicast addresses and calculate the logical
696  * address filter.
697  */
698 void
699 mace_calcladrf(ac, af)
700 	struct ethercom *ac;
701 	u_int8_t *af;
702 {
703 	struct ifnet *ifp = &ac->ec_if;
704 	struct ether_multi *enm;
705 	register u_char *cp, c;
706 	register u_int32_t crc;
707 	register int i, len;
708 	struct ether_multistep step;
709 
710 	/*
711 	 * Set up multicast address filter by passing all multicast addresses
712 	 * through a crc generator, and then using the high order 6 bits as an
713 	 * index into the 64 bit logical address filter.  The high order bit
714 	 * selects the word, while the rest of the bits select the bit within
715 	 * the word.
716 	 */
717 
718 	*((u_int32_t *)af) = *((u_int32_t *)af + 1) = 0;
719 
720 	ETHER_FIRST_MULTI(step, ac, enm);
721 	while (enm != NULL) {
722 		if (ETHER_CMP(enm->enm_addrlo, enm->enm_addrhi)) {
723 			/*
724 			 * We must listen to a range of multicast addresses.
725 			 * For now, just accept all multicasts, rather than
726 			 * trying to set only those filter bits needed to match
727 			 * the range.  (At this time, the only use of address
728 			 * ranges is for IP multicast routing, for which the
729 			 * range is big enough to require all bits set.)
730 			 */
731 			goto allmulti;
732 		}
733 
734 		cp = enm->enm_addrlo;
735 		crc = 0xffffffff;
736 		for (len = sizeof(enm->enm_addrlo); --len >= 0;) {
737 			c = *cp++;
738 			for (i = 8; --i >= 0;) {
739 				if ((crc & 0x01) ^ (c & 0x01)) {
740 					crc >>= 1;
741 					crc ^= 0xedb88320;
742 				} else
743 					crc >>= 1;
744 				c >>= 1;
745 			}
746 		}
747 		/* Just want the 6 most significant bits. */
748 		crc >>= 26;
749 
750 		/* Set the corresponding bit in the filter. */
751 		af[crc >> 3] |= 1 << (crc & 7);
752 
753 		ETHER_NEXT_MULTI(step, enm);
754 	}
755 	ifp->if_flags &= ~IFF_ALLMULTI;
756 	return;
757 
758 allmulti:
759 	ifp->if_flags |= IFF_ALLMULTI;
760 	*((u_int32_t *)af) = *((u_int32_t *)af + 1) = 0xffffffff;
761 }
762 
763 int
764 mc_mediachange(ifp)
765 	struct ifnet *ifp;
766 {
767 	return EINVAL;
768 }
769 
770 void
771 mc_mediastatus(ifp, ifmr)
772 	struct ifnet *ifp;
773 	struct ifmediareq *ifmr;
774 {
775 	struct mc_softc *sc = ifp->if_softc;
776 
777 	if ((ifp->if_flags & IFF_UP) == 0)
778 		return;
779 
780 	if (sc->sc_havecarrier)
781 		ifmr->ifm_status |= IFM_ACTIVE;
782 }
783