xref: /netbsd-src/sys/arch/macppc/dev/am79c950.c (revision fad4c9f71477ae11cea2ee75ec82151ac770a534)
1 /*	$NetBSD: am79c950.c,v 1.17 2005/12/11 12:18:03 christos 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 1.17 2005/12/11 12:18:03 christos Exp $");
39 
40 #include "opt_inet.h"
41 #include "opt_ccitt.h"
42 #include "opt_llc.h"
43 #include "opt_ns.h"
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/mbuf.h>
48 #include <sys/buf.h>
49 #include <sys/protosw.h>
50 #include <sys/socket.h>
51 #include <sys/syslog.h>
52 #include <sys/ioctl.h>
53 #include <sys/errno.h>
54 #include <sys/device.h>
55 
56 #include <uvm/uvm_extern.h>
57 
58 #include <net/if.h>
59 #include <net/if_dl.h>
60 #include <net/if_ether.h>
61 #include <net/if_media.h>
62 
63 #ifdef INET
64 #include <netinet/in.h>
65 #include <netinet/if_inarp.h>
66 #include <netinet/in_systm.h>
67 #include <netinet/in_var.h>
68 #include <netinet/ip.h>
69 #endif
70 
71 #ifdef NS
72 #include <netns/ns.h>
73 #include <netns/ns_if.h>
74 #endif
75 
76 #if defined(CCITT) && defined(LLC)
77 #include <sys/socketvar.h>
78 #include <netccitt/x25.h>
79 #include <netccitt/pk.h>
80 #include <netccitt/pk_var.h>
81 #include <netccitt/pk_extern.h>
82 #endif
83 
84 #include <uvm/uvm_extern.h>
85 
86 #include "bpfilter.h"
87 #if NBPFILTER > 0
88 #include <net/bpf.h>
89 #include <net/bpfdesc.h>
90 #endif
91 
92 #include <machine/pio.h>
93 #include <machine/bus.h>
94 
95 #include <macppc/dev/am79c950reg.h>
96 #include <macppc/dev/if_mcvar.h>
97 
98 hide void	mcwatchdog __P((struct ifnet *));
99 hide int	mcinit __P((struct mc_softc *sc));
100 hide int	mcstop __P((struct mc_softc *sc));
101 hide int	mcioctl __P((struct ifnet *ifp, u_long cmd, caddr_t data));
102 hide void	mcstart __P((struct ifnet *ifp));
103 hide void	mcreset __P((struct mc_softc *sc));
104 
105 integrate u_int	maceput __P((struct mc_softc *sc, struct mbuf *m0));
106 integrate void	mc_tint __P((struct mc_softc *sc));
107 integrate void	mace_read __P((struct mc_softc *, caddr_t, int));
108 integrate struct mbuf *mace_get __P((struct mc_softc *, caddr_t, int));
109 static void mace_calcladrf __P((struct ethercom *ac, u_int8_t *af));
110 static inline u_int16_t ether_cmp __P((void *, void *));
111 static int mc_mediachange __P((struct ifnet *));
112 static void mc_mediastatus __P((struct ifnet *, struct ifmediareq *));
113 
114 /*
115  * Compare two Ether/802 addresses for equality, inlined and
116  * unrolled for speed.  Use this like memcmp().
117  *
118  * XXX: Add <machine/inlines.h> for stuff like this?
119  * XXX: or maybe add it to libkern.h instead?
120  *
121  * "I'd love to have an inline assembler version of this."
122  * XXX: Who wanted that? mycroft?  I wrote one, but this
123  * version in C is as good as hand-coded assembly. -gwr
124  *
125  * Please do NOT tweak this without looking at the actual
126  * assembly code generated before and after your tweaks!
127  */
128 static inline u_int16_t
129 ether_cmp(one, two)
130 	void *one, *two;
131 {
132 	register u_int16_t *a = (u_short *) one;
133 	register u_int16_t *b = (u_short *) two;
134 	register u_int16_t diff;
135 
136 #ifdef	m68k
137 	/*
138 	 * The post-increment-pointer form produces the best
139 	 * machine code for m68k.  This was carefully tuned
140 	 * so it compiles to just 8 short (2-byte) op-codes!
141 	 */
142 	diff  = *a++ - *b++;
143 	diff |= *a++ - *b++;
144 	diff |= *a++ - *b++;
145 #else
146 	/*
147 	 * Most modern CPUs do better with a single expresion.
148 	 * Note that short-cut evaluation is NOT helpful here,
149 	 * because it just makes the code longer, not faster!
150 	 */
151 	diff = (a[0] - b[0]) | (a[1] - b[1]) | (a[2] - b[2]);
152 #endif
153 
154 	return (diff);
155 }
156 
157 #define ETHER_CMP	ether_cmp
158 
159 /*
160  * Interface exists: make available by filling in network interface
161  * record.  System will initialize the interface when it is ready
162  * to accept packets.
163  */
164 int
165 mcsetup(sc, lladdr)
166 	struct mc_softc	*sc;
167 	u_int8_t *lladdr;
168 {
169 	struct ifnet *ifp = &sc->sc_if;
170 
171 	/* reset the chip and disable all interrupts */
172 	NIC_PUT(sc, MACE_BIUCC, SWRST);
173 	DELAY(100);
174 	NIC_PUT(sc, MACE_IMR, ~0);
175 
176 	memcpy(sc->sc_enaddr, lladdr, ETHER_ADDR_LEN);
177 	printf(": address %s\n", ether_sprintf(lladdr));
178 
179 	memcpy(ifp->if_xname, sc->sc_dev.dv_xname, IFNAMSIZ);
180 	ifp->if_softc = sc;
181 	ifp->if_ioctl = mcioctl;
182 	ifp->if_start = mcstart;
183 	ifp->if_flags =
184 	    IFF_BROADCAST | IFF_SIMPLEX | IFF_NOTRAILERS | IFF_MULTICAST;
185 	ifp->if_watchdog = mcwatchdog;
186 
187 	/* initialize ifmedia structures */
188 	ifmedia_init(&sc->sc_media, 0, mc_mediachange, mc_mediastatus);
189 	ifmedia_add(&sc->sc_media, IFM_ETHER|IFM_MANUAL, 0, NULL);
190 	ifmedia_set(&sc->sc_media, IFM_ETHER|IFM_MANUAL);
191 
192 	if_attach(ifp);
193 	ether_ifattach(ifp, lladdr);
194 
195 	return (0);
196 }
197 
198 hide int
199 mcioctl(ifp, cmd, data)
200 	struct ifnet *ifp;
201 	u_long cmd;
202 	caddr_t data;
203 {
204 	struct mc_softc *sc = ifp->if_softc;
205 	struct ifaddr *ifa;
206 	struct ifreq *ifr;
207 
208 	int	s = splnet(), err = 0;
209 
210 	switch (cmd) {
211 
212 	case SIOCSIFADDR:
213 		ifa = (struct ifaddr *)data;
214 		ifp->if_flags |= IFF_UP;
215 		switch (ifa->ifa_addr->sa_family) {
216 #ifdef INET
217 		case AF_INET:
218 			mcinit(sc);
219 			arp_ifinit(ifp, ifa);
220 			break;
221 #endif
222 #ifdef NS
223 		case AF_NS:
224 		    {
225 			register struct ns_addr *ina = &IA_SNS(ifa)->sns_addr;
226 
227 			if (ns_nullhost(*ina))
228 				ina->x_host =
229 				    *(union ns_host *)LLADDR(ifp->if_sadl);
230 			else {
231 				memcpy(LLADDR(ifp->if_sadl),
232 				    ina->x_host.c_host,
233 				    sizeof(sc->sc_enaddr));
234 			}
235 			/* Set new address. */
236 			mcinit(sc);
237 			break;
238 		    }
239 #endif
240 		default:
241 			mcinit(sc);
242 			break;
243 		}
244 		break;
245 
246 	case SIOCSIFFLAGS:
247 		if ((ifp->if_flags & IFF_UP) == 0 &&
248 		    (ifp->if_flags & IFF_RUNNING) != 0) {
249 			/*
250 			 * If interface is marked down and it is running,
251 			 * then stop it.
252 			 */
253 			mcstop(sc);
254 			ifp->if_flags &= ~IFF_RUNNING;
255 		} else if ((ifp->if_flags & IFF_UP) != 0 &&
256 		    (ifp->if_flags & IFF_RUNNING) == 0) {
257 			/*
258 			 * If interface is marked up and it is stopped,
259 			 * then start it.
260 			 */
261 			(void)mcinit(sc);
262 		} else {
263 			/*
264 			 * reset the interface to pick up any other changes
265 			 * in flags
266 			 */
267 			mcreset(sc);
268 			mcstart(ifp);
269 		}
270 		break;
271 
272 	case SIOCADDMULTI:
273 	case SIOCDELMULTI:
274 		ifr = (struct ifreq *) data;
275 		err = (cmd == SIOCADDMULTI) ?
276 		    ether_addmulti(ifr, &sc->sc_ethercom) :
277 		    ether_delmulti(ifr, &sc->sc_ethercom);
278 
279 		if (err == ENETRESET) {
280 			/*
281 			 * Multicast list has changed; set the hardware
282 			 * filter accordingly. But remember UP flag!
283 			 */
284 			if (ifp->if_flags & IFF_RUNNING)
285 				mcreset(sc);
286 			err = 0;
287 		}
288 		break;
289 
290 	case SIOCGIFMEDIA:
291 	case SIOCSIFMEDIA:
292 		ifr = (struct ifreq *) data;
293 		err = ifmedia_ioctl(ifp, ifr, &sc->sc_media, cmd);
294 		break;
295 
296 	default:
297 		err = EINVAL;
298 	}
299 	splx(s);
300 	return (err);
301 }
302 
303 /*
304  * Encapsulate a packet of type family for the local net.
305  */
306 hide void
307 mcstart(ifp)
308 	struct ifnet *ifp;
309 {
310 	struct mc_softc	*sc = ifp->if_softc;
311 	struct mbuf	*m;
312 
313 	if ((ifp->if_flags & (IFF_RUNNING | IFF_OACTIVE)) != IFF_RUNNING)
314 		return;
315 
316 	while (1) {
317 		if (ifp->if_flags & IFF_OACTIVE)
318 			return;
319 
320 		IF_DEQUEUE(&ifp->if_snd, m);
321 		if (m == 0)
322 			return;
323 
324 #if NBPFILTER > 0
325 		/*
326 		 * If bpf is listening on this interface, let it
327 		 * see the packet before we commit it to the wire.
328 		 */
329 		if (ifp->if_bpf)
330 			bpf_mtap(ifp->if_bpf, m);
331 #endif
332 
333 		/*
334 		 * Copy the mbuf chain into the transmit buffer.
335 		 */
336 		ifp->if_flags |= IFF_OACTIVE;
337 		maceput(sc, m);
338 
339 		ifp->if_opackets++;		/* # of pkts */
340 	}
341 }
342 
343 /*
344  * reset and restart the MACE.  Called in case of fatal
345  * hardware/software errors.
346  */
347 hide void
348 mcreset(sc)
349 	struct mc_softc *sc;
350 {
351 	mcstop(sc);
352 	mcinit(sc);
353 }
354 
355 hide int
356 mcinit(sc)
357 	struct mc_softc *sc;
358 {
359 	int s;
360 	u_int8_t maccc, ladrf[8];
361 
362 	if (sc->sc_if.if_flags & IFF_RUNNING)
363 		/* already running */
364 		return (0);
365 
366 	s = splnet();
367 
368 	NIC_PUT(sc, MACE_BIUCC, sc->sc_biucc);
369 	NIC_PUT(sc, MACE_FIFOCC, sc->sc_fifocc);
370 	NIC_PUT(sc, MACE_IMR, ~0); /* disable all interrupts */
371 	NIC_PUT(sc, MACE_PLSCC, sc->sc_plscc);
372 
373 	NIC_PUT(sc, MACE_UTR, RTRD); /* disable reserved test registers */
374 
375 	/* set MAC address */
376 	NIC_PUT(sc, MACE_IAC, ADDRCHG);
377 	while (NIC_GET(sc, MACE_IAC) & ADDRCHG)
378 		;
379 	NIC_PUT(sc, MACE_IAC, PHYADDR);
380 	bus_space_write_multi_1(sc->sc_regt, sc->sc_regh, MACE_REG(MACE_PADR),
381 	    sc->sc_enaddr, ETHER_ADDR_LEN);
382 
383 	/* set logical address filter */
384 	mace_calcladrf(&sc->sc_ethercom, ladrf);
385 
386 	NIC_PUT(sc, MACE_IAC, ADDRCHG);
387 	while (NIC_GET(sc, MACE_IAC) & ADDRCHG)
388 		;
389 	NIC_PUT(sc, MACE_IAC, LOGADDR);
390 	bus_space_write_multi_1(sc->sc_regt, sc->sc_regh, MACE_REG(MACE_LADRF),
391 	    ladrf, 8);
392 
393 	NIC_PUT(sc, MACE_XMTFC, APADXMT);
394 	/*
395 	 * No need to autostrip padding on receive... Ethernet frames
396 	 * don't have a length field, unlike 802.3 frames, so the MACE
397 	 * can't figure out the length of the packet anyways.
398 	 */
399 	NIC_PUT(sc, MACE_RCVFC, 0);
400 
401 	maccc = ENXMT | ENRCV;
402 	if (sc->sc_if.if_flags & IFF_PROMISC)
403 		maccc |= PROM;
404 
405 	NIC_PUT(sc, MACE_MACCC, maccc);
406 
407 	if (sc->sc_bus_init)
408 		(*sc->sc_bus_init)(sc);
409 
410 	/*
411 	 * Enable all interrupts except receive, since we use the DMA
412 	 * completion interrupt for that.
413 	 */
414 	NIC_PUT(sc, MACE_IMR, RCVINTM);
415 
416 	/* flag interface as "running" */
417 	sc->sc_if.if_flags |= IFF_RUNNING;
418 	sc->sc_if.if_flags &= ~IFF_OACTIVE;
419 
420 	splx(s);
421 	return (0);
422 }
423 
424 /*
425  * close down an interface and free its buffers
426  * Called on final close of device, or if mcinit() fails
427  * part way through.
428  */
429 hide int
430 mcstop(sc)
431 	struct mc_softc *sc;
432 {
433 	int	s = splnet();
434 
435 	NIC_PUT(sc, MACE_BIUCC, SWRST);
436 	DELAY(100);
437 
438 	sc->sc_if.if_timer = 0;
439 	sc->sc_if.if_flags &= ~IFF_RUNNING;
440 
441 	splx(s);
442 	return (0);
443 }
444 
445 /*
446  * Called if any Tx packets remain unsent after 5 seconds,
447  * In all cases we just reset the chip, and any retransmission
448  * will be handled by higher level protocol timeouts.
449  */
450 hide void
451 mcwatchdog(ifp)
452 	struct ifnet *ifp;
453 {
454 	struct mc_softc *sc = ifp->if_softc;
455 
456 	printf("mcwatchdog: resetting chip\n");
457 	mcreset(sc);
458 }
459 
460 /*
461  * stuff packet into MACE (at splnet)
462  */
463 integrate u_int
464 maceput(sc, m)
465 	struct mc_softc *sc;
466 	struct mbuf *m;
467 {
468 	struct mbuf *n;
469 	u_int len, totlen = 0;
470 	u_char *buff;
471 
472 	buff = sc->sc_txbuf;
473 
474 	for (; m; m = n) {
475 		u_char *data = mtod(m, u_char *);
476 		len = m->m_len;
477 		totlen += len;
478 		memcpy(buff, data, len);
479 		buff += len;
480 		MFREE(m, n);
481 	}
482 
483 	if (totlen > PAGE_SIZE)
484 		panic("%s: maceput: packet overflow", sc->sc_dev.dv_xname);
485 
486 #if 0
487 	if (totlen < ETHERMIN + sizeof(struct ether_header)) {
488 		int pad = ETHERMIN + sizeof(struct ether_header) - totlen;
489 		memset(sc->sc_txbuf + totlen, 0, pad);
490 		totlen = ETHERMIN + sizeof(struct ether_header);
491 	}
492 #endif
493 
494 	(*sc->sc_putpacket)(sc, totlen);
495 
496 	sc->sc_if.if_timer = 5;	/* 5 seconds to watch for failing to transmit */
497 	return (totlen);
498 }
499 
500 int
501 mcintr(arg)
502 	void *arg;
503 {
504 	struct mc_softc *sc = arg;
505 	u_int8_t ir;
506 
507 	ir = NIC_GET(sc, MACE_IR) & ~NIC_GET(sc, MACE_IMR);
508 	if (ir == 0)
509 		return 0;
510 
511 	if (ir & JAB) {
512 #ifdef MCDEBUG
513 		printf("%s: jabber error\n", sc->sc_dev.dv_xname);
514 #endif
515 		sc->sc_if.if_oerrors++;
516 	}
517 
518 	if (ir & BABL) {
519 #ifdef MCDEBUG
520 		printf("%s: babble\n", sc->sc_dev.dv_xname);
521 #endif
522 		sc->sc_if.if_oerrors++;
523 	}
524 
525 	if (ir & CERR) {
526 		printf("%s: collision error\n", sc->sc_dev.dv_xname);
527 		sc->sc_if.if_collisions++;
528 	}
529 
530 	/*
531 	 * Pretend we have carrier; if we don't this will be cleared
532 	 * shortly.
533 	 */
534 	sc->sc_havecarrier = 1;
535 
536 	if (ir & XMTINT)
537 		mc_tint(sc);
538 
539 	if (ir & RCVINT)
540 		mc_rint(sc);
541 
542 	return 1;
543 }
544 
545 integrate void
546 mc_tint(sc)
547 	struct mc_softc *sc;
548 {
549 	u_int8_t xmtrc, xmtfs;
550 
551 	xmtrc = NIC_GET(sc, MACE_XMTRC);
552 	xmtfs = NIC_GET(sc, MACE_XMTFS);
553 
554 	if ((xmtfs & XMTSV) == 0)
555 		return;
556 
557 	if (xmtfs & UFLO) {
558 		printf("%s: underflow\n", sc->sc_dev.dv_xname);
559 		mcreset(sc);
560 		return;
561 	}
562 
563 	if (xmtfs & LCOL) {
564 		printf("%s: late collision\n", sc->sc_dev.dv_xname);
565 		sc->sc_if.if_oerrors++;
566 		sc->sc_if.if_collisions++;
567 	}
568 
569 	if (xmtfs & MORE)
570 		/* Real number is unknown. */
571 		sc->sc_if.if_collisions += 2;
572 	else if (xmtfs & ONE)
573 		sc->sc_if.if_collisions++;
574 	else if (xmtfs & RTRY) {
575 		sc->sc_if.if_collisions += 16;
576 		sc->sc_if.if_oerrors++;
577 	}
578 
579 	if (xmtfs & LCAR) {
580 		sc->sc_havecarrier = 0;
581 		printf("%s: lost carrier\n", sc->sc_dev.dv_xname);
582 		sc->sc_if.if_oerrors++;
583 	}
584 
585 	sc->sc_if.if_flags &= ~IFF_OACTIVE;
586 	sc->sc_if.if_timer = 0;
587 	mcstart(&sc->sc_if);
588 }
589 
590 void
591 mc_rint(sc)
592 	struct mc_softc *sc;
593 {
594 #define	rxf	sc->sc_rxframe
595 	u_int len;
596 
597 	len = (rxf.rx_rcvcnt | ((rxf.rx_rcvsts & 0xf) << 8)) - 4;
598 
599 #ifdef MCDEBUG
600 	if (rxf.rx_rcvsts & 0xf0)
601 		printf("%s: rcvcnt %02x rcvsts %02x rntpc 0x%02x rcvcc 0x%02x\n",
602 		    sc->sc_dev.dv_xname, rxf.rx_rcvcnt, rxf.rx_rcvsts,
603 		    rxf.rx_rntpc, rxf.rx_rcvcc);
604 #endif
605 
606 	if (rxf.rx_rcvsts & OFLO) {
607 		printf("%s: receive FIFO overflow\n", sc->sc_dev.dv_xname);
608 		sc->sc_if.if_ierrors++;
609 		return;
610 	}
611 
612 	if (rxf.rx_rcvsts & CLSN)
613 		sc->sc_if.if_collisions++;
614 
615 	if (rxf.rx_rcvsts & FRAM) {
616 #ifdef MCDEBUG
617 		printf("%s: framing error\n", sc->sc_dev.dv_xname);
618 #endif
619 		sc->sc_if.if_ierrors++;
620 		return;
621 	}
622 
623 	if (rxf.rx_rcvsts & FCS) {
624 #ifdef MCDEBUG
625 		printf("%s: frame control checksum error\n", sc->sc_dev.dv_xname);
626 #endif
627 		sc->sc_if.if_ierrors++;
628 		return;
629 	}
630 
631 	mace_read(sc, rxf.rx_frame, len);
632 #undef	rxf
633 }
634 
635 integrate void
636 mace_read(sc, pkt, len)
637 	struct mc_softc *sc;
638 	caddr_t pkt;
639 	int len;
640 {
641 	struct ifnet *ifp = &sc->sc_if;
642 	struct mbuf *m;
643 
644 	if (len <= sizeof(struct ether_header) ||
645 	    len > ETHERMTU + sizeof(struct ether_header)) {
646 #ifdef MCDEBUG
647 		printf("%s: invalid packet size %d; dropping\n",
648 		    sc->sc_dev.dv_xname, len);
649 #endif
650 		ifp->if_ierrors++;
651 		return;
652 	}
653 
654 	m = mace_get(sc, pkt, len);
655 	if (m == NULL) {
656 		ifp->if_ierrors++;
657 		return;
658 	}
659 
660 	ifp->if_ipackets++;
661 
662 #if NBPFILTER > 0
663 	/* Pass this up to any BPF listeners. */
664 	if (ifp->if_bpf)
665 		bpf_mtap(ifp->if_bpf, m);
666 #endif
667 
668 	/* Pass the packet up. */
669 	(*ifp->if_input)(ifp, m);
670 }
671 
672 /*
673  * Pull data off an interface.
674  * Len is length of data, with local net header stripped.
675  * We copy the data into mbufs.  When full cluster sized units are present
676  * we copy into clusters.
677  */
678 integrate struct mbuf *
679 mace_get(sc, pkt, totlen)
680 	struct mc_softc *sc;
681 	caddr_t pkt;
682 	int totlen;
683 {
684 	register struct mbuf *m;
685 	struct mbuf *top, **mp;
686 	int len;
687 
688 	MGETHDR(m, M_DONTWAIT, MT_DATA);
689 	if (m == 0)
690 		return (0);
691 	m->m_pkthdr.rcvif = &sc->sc_if;
692 	m->m_pkthdr.len = totlen;
693 	len = MHLEN;
694 	top = 0;
695 	mp = &top;
696 
697 	while (totlen > 0) {
698 		if (top) {
699 			MGET(m, M_DONTWAIT, MT_DATA);
700 			if (m == 0) {
701 				m_freem(top);
702 				return 0;
703 			}
704 			len = MLEN;
705 		}
706 		if (totlen >= MINCLSIZE) {
707 			MCLGET(m, M_DONTWAIT);
708 			if ((m->m_flags & M_EXT) == 0) {
709 				m_free(m);
710 				m_freem(top);
711 				return 0;
712 			}
713 			len = MCLBYTES;
714 		}
715 		m->m_len = len = min(totlen, len);
716 		memcpy(mtod(m, caddr_t), pkt, len);
717 		pkt += len;
718 		totlen -= len;
719 		*mp = m;
720 		mp = &m->m_next;
721 	}
722 
723 	return (top);
724 }
725 
726 /*
727  * Go through the list of multicast addresses and calculate the logical
728  * address filter.
729  */
730 void
731 mace_calcladrf(ac, af)
732 	struct ethercom *ac;
733 	u_int8_t *af;
734 {
735 	struct ifnet *ifp = &ac->ec_if;
736 	struct ether_multi *enm;
737 	register u_char *cp, c;
738 	register u_int32_t crc;
739 	register int i, len;
740 	struct ether_multistep step;
741 
742 	/*
743 	 * Set up multicast address filter by passing all multicast addresses
744 	 * through a crc generator, and then using the high order 6 bits as an
745 	 * index into the 64 bit logical address filter.  The high order bit
746 	 * selects the word, while the rest of the bits select the bit within
747 	 * the word.
748 	 */
749 
750 	*((u_int32_t *)af) = *((u_int32_t *)af + 1) = 0;
751 
752 	ETHER_FIRST_MULTI(step, ac, enm);
753 	while (enm != NULL) {
754 		if (ETHER_CMP(enm->enm_addrlo, enm->enm_addrhi)) {
755 			/*
756 			 * We must listen to a range of multicast addresses.
757 			 * For now, just accept all multicasts, rather than
758 			 * trying to set only those filter bits needed to match
759 			 * the range.  (At this time, the only use of address
760 			 * ranges is for IP multicast routing, for which the
761 			 * range is big enough to require all bits set.)
762 			 */
763 			goto allmulti;
764 		}
765 
766 		cp = enm->enm_addrlo;
767 		crc = 0xffffffff;
768 		for (len = sizeof(enm->enm_addrlo); --len >= 0;) {
769 			c = *cp++;
770 			for (i = 8; --i >= 0;) {
771 				if ((crc & 0x01) ^ (c & 0x01)) {
772 					crc >>= 1;
773 					crc ^= 0xedb88320;
774 				} else
775 					crc >>= 1;
776 				c >>= 1;
777 			}
778 		}
779 		/* Just want the 6 most significant bits. */
780 		crc >>= 26;
781 
782 		/* Set the corresponding bit in the filter. */
783 		af[crc >> 3] |= 1 << (crc & 7);
784 
785 		ETHER_NEXT_MULTI(step, enm);
786 	}
787 	ifp->if_flags &= ~IFF_ALLMULTI;
788 	return;
789 
790 allmulti:
791 	ifp->if_flags |= IFF_ALLMULTI;
792 	*((u_int32_t *)af) = *((u_int32_t *)af + 1) = 0xffffffff;
793 }
794 
795 int
796 mc_mediachange(ifp)
797 	struct ifnet *ifp;
798 {
799 	return EINVAL;
800 }
801 
802 void
803 mc_mediastatus(ifp, ifmr)
804 	struct ifnet *ifp;
805 	struct ifmediareq *ifmr;
806 {
807 	struct mc_softc *sc = ifp->if_softc;
808 
809 	if ((ifp->if_flags & IFF_UP) == 0)
810 		return;
811 
812 	if (sc->sc_havecarrier)
813 		ifmr->ifm_status |= IFM_ACTIVE;
814 }
815