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      1 /*	$NetBSD: lance.c,v 1.62 2024/11/17 09:28:34 hannken Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1997, 1998 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Charles M. Hannum and by Jason R. Thorpe of the Numerical Aerospace
      9  * Simulation Facility, NASA Ames Research Center.
     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. Redistributions in binary form must reproduce the above copyright
     17  *    notice, this list of conditions and the following disclaimer in the
     18  *    documentation and/or other materials provided with the distribution.
     19  *
     20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     30  * POSSIBILITY OF SUCH DAMAGE.
     31  */
     32 
     33 /*-
     34  * Copyright (c) 1992, 1993
     35  *	The Regents of the University of California.  All rights reserved.
     36  *
     37  * This code is derived from software contributed to Berkeley by
     38  * Ralph Campbell and Rick Macklem.
     39  *
     40  * Redistribution and use in source and binary forms, with or without
     41  * modification, are permitted provided that the following conditions
     42  * are met:
     43  * 1. Redistributions of source code must retain the above copyright
     44  *    notice, this list of conditions and the following disclaimer.
     45  * 2. Redistributions in binary form must reproduce the above copyright
     46  *    notice, this list of conditions and the following disclaimer in the
     47  *    documentation and/or other materials provided with the distribution.
     48  * 3. Neither the name of the University nor the names of its contributors
     49  *    may be used to endorse or promote products derived from this software
     50  *    without specific prior written permission.
     51  *
     52  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     62  * SUCH DAMAGE.
     63  *
     64  *	@(#)if_le.c	8.2 (Berkeley) 11/16/93
     65  */
     66 
     67 #include <sys/cdefs.h>
     68 __KERNEL_RCSID(0, "$NetBSD: lance.c,v 1.62 2024/11/17 09:28:34 hannken Exp $");
     69 
     70 #include <sys/param.h>
     71 #include <sys/systm.h>
     72 #include <sys/mbuf.h>
     73 #include <sys/syslog.h>
     74 #include <sys/socket.h>
     75 #include <sys/device.h>
     76 #include <sys/malloc.h>
     77 #include <sys/ioctl.h>
     78 #include <sys/errno.h>
     79 #include <sys/rndsource.h>
     80 
     81 #include <net/if.h>
     82 #include <net/if_dl.h>
     83 #include <net/if_ether.h>
     84 #include <net/if_media.h>
     85 #include <net/bpf.h>
     86 
     87 #include <dev/ic/lancereg.h>
     88 #include <dev/ic/lancevar.h>
     89 
     90 #if defined(_KERNEL_OPT)
     91 #include "opt_ddb.h"
     92 #endif
     93 
     94 #ifdef DDB
     95 #define	integrate
     96 #define hide
     97 #else
     98 #define	integrate	static inline
     99 #define hide		static
    100 #endif
    101 
    102 integrate struct mbuf *lance_get(struct lance_softc *, int, int);
    103 
    104 hide bool lance_shutdown(device_t, int);
    105 
    106 int lance_mediachange(struct ifnet *);
    107 void lance_mediastatus(struct ifnet *, struct ifmediareq *);
    108 
    109 static inline uint16_t ether_cmp(void *, void *);
    110 
    111 void lance_stop(struct ifnet *, int);
    112 int lance_ioctl(struct ifnet *, u_long, void *);
    113 void lance_watchdog(struct ifnet *);
    114 
    115 /*
    116  * Compare two Ether/802 addresses for equality, inlined and
    117  * unrolled for speed.  Use this like memcmp().
    118  *
    119  * XXX: Add <machine/inlines.h> for stuff like this?
    120  * XXX: or maybe add it to libkern.h instead?
    121  *
    122  * "I'd love to have an inline assembler version of this."
    123  * XXX: Who wanted that? mycroft?  I wrote one, but this
    124  * version in C is as good as hand-coded assembly. -gwr
    125  *
    126  * Please do NOT tweak this without looking at the actual
    127  * assembly code generated before and after your tweaks!
    128  */
    129 static inline uint16_t
    130 ether_cmp(void *one, void *two)
    131 {
    132 	uint16_t *a = (uint16_t *)one;
    133 	uint16_t *b = (uint16_t *)two;
    134 	uint16_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 expression.
    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 #ifdef LANCE_REVC_BUG
    160 /* Make sure this is short-aligned, for ether_cmp(). */
    161 static uint16_t bcast_enaddr[3] = { ~0, ~0, ~0 };
    162 #endif
    163 
    164 void
    165 lance_config(struct lance_softc *sc)
    166 {
    167 	int i, nbuf;
    168 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
    169 
    170 	/* Initialize ifnet structure. */
    171 	strcpy(ifp->if_xname, device_xname(sc->sc_dev));
    172 	ifp->if_softc = sc;
    173 	ifp->if_start = sc->sc_start;
    174 	ifp->if_ioctl = lance_ioctl;
    175 	ifp->if_watchdog = lance_watchdog;
    176 	ifp->if_init = lance_init;
    177 	ifp->if_stop = lance_stop;
    178 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
    179 #ifdef LANCE_REVC_BUG
    180 	ifp->if_flags &= ~IFF_MULTICAST;
    181 #endif
    182 	IFQ_SET_READY(&ifp->if_snd);
    183 
    184 	/* Initialize ifmedia structures. */
    185 	sc->sc_ethercom.ec_ifmedia = &sc->sc_media;
    186 	ifmedia_init(&sc->sc_media, 0, lance_mediachange, lance_mediastatus);
    187 	if (sc->sc_supmedia != NULL) {
    188 		for (i = 0; i < sc->sc_nsupmedia; i++)
    189 			ifmedia_add(&sc->sc_media, sc->sc_supmedia[i],
    190 			   0, NULL);
    191 		ifmedia_set(&sc->sc_media, sc->sc_defaultmedia);
    192 	} else {
    193 		ifmedia_add(&sc->sc_media, IFM_ETHER | IFM_MANUAL, 0, NULL);
    194 		ifmedia_set(&sc->sc_media, IFM_ETHER | IFM_MANUAL);
    195 	}
    196 
    197 	switch (sc->sc_memsize) {
    198 	case 8192:
    199 		sc->sc_nrbuf = 4;
    200 		sc->sc_ntbuf = 1;
    201 		break;
    202 	case 16384:
    203 		sc->sc_nrbuf = 8;
    204 		sc->sc_ntbuf = 2;
    205 		break;
    206 	case 32768:
    207 		sc->sc_nrbuf = 16;
    208 		sc->sc_ntbuf = 4;
    209 		break;
    210 	case 65536:
    211 		sc->sc_nrbuf = 32;
    212 		sc->sc_ntbuf = 8;
    213 		break;
    214 	case 131072:
    215 		sc->sc_nrbuf = 64;
    216 		sc->sc_ntbuf = 16;
    217 		break;
    218 	case 262144:
    219 		sc->sc_nrbuf = 128;
    220 		sc->sc_ntbuf = 32;
    221 		break;
    222 	default:
    223 		/* weird memory size; cope with it */
    224 		nbuf = sc->sc_memsize / LEBLEN;
    225 		sc->sc_ntbuf = nbuf / 5;
    226 		sc->sc_nrbuf = nbuf - sc->sc_ntbuf;
    227 	}
    228 
    229 	aprint_normal(": address %s\n", ether_sprintf(sc->sc_enaddr));
    230 	aprint_normal_dev(sc->sc_dev,
    231 	    "%d receive buffers, %d transmit buffers\n",
    232 	    sc->sc_nrbuf, sc->sc_ntbuf);
    233 
    234 	/* Make sure the chip is stopped. */
    235 	lance_stop(ifp, 0);
    236 
    237 	/* claim 802.1q capability */
    238 	sc->sc_ethercom.ec_capabilities |= ETHERCAP_VLAN_MTU;
    239 	/* Attach the interface. */
    240 	if_attach(ifp);
    241 	ether_ifattach(ifp, sc->sc_enaddr);
    242 
    243 	if (pmf_device_register1(sc->sc_dev, NULL, NULL, lance_shutdown))
    244 		pmf_class_network_register(sc->sc_dev, ifp);
    245 	else
    246 		aprint_error_dev(sc->sc_dev,
    247 		    "couldn't establish power handler\n");
    248 
    249 	sc->sc_rbufaddr = malloc(sc->sc_nrbuf * sizeof(int), M_DEVBUF,
    250 					M_WAITOK);
    251 	sc->sc_tbufaddr = malloc(sc->sc_ntbuf * sizeof(int), M_DEVBUF,
    252 					M_WAITOK);
    253 
    254 	rnd_attach_source(&sc->rnd_source, device_xname(sc->sc_dev),
    255 			  RND_TYPE_NET, RND_FLAG_DEFAULT);
    256 }
    257 
    258 void
    259 lance_reset(struct lance_softc *sc)
    260 {
    261 	int s;
    262 
    263 	s = splnet();
    264 	lance_init(&sc->sc_ethercom.ec_if);
    265 	splx(s);
    266 }
    267 
    268 void
    269 lance_stop(struct ifnet *ifp, int disable)
    270 {
    271 	struct lance_softc *sc = ifp->if_softc;
    272 
    273 	(*sc->sc_wrcsr)(sc, LE_CSR0, LE_C0_STOP);
    274 }
    275 
    276 /*
    277  * Initialization of interface; set up initialization block
    278  * and transmit/receive descriptor rings.
    279  */
    280 int
    281 lance_init(struct ifnet *ifp)
    282 {
    283 	struct lance_softc *sc = ifp->if_softc;
    284 	int timo;
    285 	u_long a;
    286 
    287 	(*sc->sc_wrcsr)(sc, LE_CSR0, LE_C0_STOP);
    288 	DELAY(100);
    289 
    290 	/* Newer LANCE chips have a reset register */
    291 	if (sc->sc_hwreset)
    292 		(*sc->sc_hwreset)(sc);
    293 
    294 	/* Set the correct byte swapping mode, etc. */
    295 	(*sc->sc_wrcsr)(sc, LE_CSR3, sc->sc_conf3);
    296 
    297 	/* Set up LANCE init block. */
    298 	(*sc->sc_meminit)(sc);
    299 
    300 	/* Give LANCE the physical address of its init block. */
    301 	a = sc->sc_addr + LE_INITADDR(sc);
    302 	(*sc->sc_wrcsr)(sc, LE_CSR1, a);
    303 	(*sc->sc_wrcsr)(sc, LE_CSR2, a >> 16);
    304 
    305 	/* Try to initialize the LANCE. */
    306 	DELAY(100);
    307 	(*sc->sc_wrcsr)(sc, LE_CSR0, LE_C0_INIT);
    308 
    309 	/* Wait for initialization to finish. */
    310 	for (timo = 100000; timo; timo--)
    311 		if ((*sc->sc_rdcsr)(sc, LE_CSR0) & LE_C0_IDON)
    312 			break;
    313 
    314 	if ((*sc->sc_rdcsr)(sc, LE_CSR0) & LE_C0_IDON) {
    315 		/* Start the LANCE. */
    316 		(*sc->sc_wrcsr)(sc, LE_CSR0, LE_C0_INEA | LE_C0_STRT);
    317 		ifp->if_flags |= IFF_RUNNING;
    318 		ifp->if_flags &= ~IFF_OACTIVE;
    319 		ifp->if_timer = 0;
    320 		(*sc->sc_start)(ifp);
    321 	} else
    322 		printf("%s: controller failed to initialize\n",
    323 			device_xname(sc->sc_dev));
    324 	if (sc->sc_hwinit)
    325 		(*sc->sc_hwinit)(sc);
    326 
    327 	return (0);
    328 }
    329 
    330 /*
    331  * Routine to copy from mbuf chain to transmit buffer in
    332  * network buffer memory.
    333  */
    334 int
    335 lance_put(struct lance_softc *sc, int boff, struct mbuf *m)
    336 {
    337 	struct mbuf *n;
    338 	int len, tlen = 0;
    339 
    340 	for (; m; m = n) {
    341 		len = m->m_len;
    342 		if (len == 0) {
    343 			n = m_free(m);
    344 			continue;
    345 		}
    346 		(*sc->sc_copytobuf)(sc, mtod(m, void *), boff, len);
    347 		boff += len;
    348 		tlen += len;
    349 		n = m_free(m);
    350 	}
    351 	if (tlen < LEMINSIZE) {
    352 		(*sc->sc_zerobuf)(sc, boff, LEMINSIZE - tlen);
    353 		tlen = LEMINSIZE;
    354 	}
    355 	return (tlen);
    356 }
    357 
    358 /*
    359  * Pull data off an interface.
    360  * Len is length of data, with local net header stripped.
    361  * We copy the data into mbufs.  When full cluster sized units are present
    362  * we copy into clusters.
    363  */
    364 integrate struct mbuf *
    365 lance_get(struct lance_softc *sc, int boff, int totlen)
    366 {
    367 	struct mbuf *m, *m0, *newm;
    368 	int len;
    369 
    370 	MGETHDR(m0, M_DONTWAIT, MT_DATA);
    371 	if (m0 == 0)
    372 		return (0);
    373 	MCLAIM(m0, &sc->sc_ethercom.ec_rx_mowner);
    374 	m_set_rcvif(m0, &sc->sc_ethercom.ec_if);
    375 	m0->m_pkthdr.len = totlen;
    376 	len = MHLEN;
    377 	m = m0;
    378 
    379 	while (totlen > 0) {
    380 		if (totlen >= MINCLSIZE) {
    381 			MCLGET(m, M_DONTWAIT);
    382 			if ((m->m_flags & M_EXT) == 0)
    383 				goto bad;
    384 			len = MCLBYTES;
    385 		}
    386 
    387 		if (m == m0) {
    388 			char *newdata = (char *)
    389 			    ALIGN(m->m_data + sizeof(struct ether_header)) -
    390 			    sizeof(struct ether_header);
    391 			len -= newdata - m->m_data;
    392 			m->m_data = newdata;
    393 		}
    394 
    395 		m->m_len = len = uimin(totlen, len);
    396 		(*sc->sc_copyfrombuf)(sc, mtod(m, void *), boff, len);
    397 		boff += len;
    398 
    399 		totlen -= len;
    400 		if (totlen > 0) {
    401 			MGET(newm, M_DONTWAIT, MT_DATA);
    402 			if (newm == 0)
    403 				goto bad;
    404 			MCLAIM(newm, &sc->sc_ethercom.ec_rx_mowner);
    405 			len = MLEN;
    406 			m = m->m_next = newm;
    407 		}
    408 	}
    409 
    410 	return (m0);
    411 
    412 bad:
    413 	m_freem(m0);
    414 	return (0);
    415 }
    416 
    417 /*
    418  * Pass a packet to the higher levels.
    419  */
    420 void
    421 lance_read(struct lance_softc *sc, int boff, int len)
    422 {
    423 	struct mbuf *m;
    424 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
    425 	struct ether_header *eh;
    426 
    427 	if (len <= sizeof(struct ether_header) ||
    428 	    len > ((sc->sc_ethercom.ec_capenable & ETHERCAP_VLAN_MTU) ?
    429 		ETHER_VLAN_ENCAP_LEN + ETHERMTU + sizeof(struct ether_header) :
    430 		ETHERMTU + sizeof(struct ether_header))) {
    431 #ifdef LEDEBUG
    432 		printf("%s: invalid packet size %d; dropping\n",
    433 		    device_xname(sc->sc_dev), len);
    434 #endif
    435 		if_statinc(ifp, if_ierrors);
    436 		return;
    437 	}
    438 
    439 	/* Pull packet off interface. */
    440 	m = lance_get(sc, boff, len);
    441 	if (m == 0) {
    442 		if_statinc(ifp, if_ierrors);
    443 		return;
    444 	}
    445 
    446 	eh = mtod(m, struct ether_header *);
    447 
    448 #ifdef LANCE_REVC_BUG
    449 	/*
    450 	 * The old LANCE (Rev. C) chips have a bug which causes
    451 	 * garbage to be inserted in front of the received packet.
    452 	 * The work-around is to ignore packets with an invalid
    453 	 * destination address (garbage will usually not match).
    454 	 * Of course, this precludes multicast support...
    455 	 */
    456 	if (ETHER_CMP(eh->ether_dhost, sc->sc_enaddr) &&
    457 	    ETHER_CMP(eh->ether_dhost, bcast_enaddr)) {
    458 		m_freem(m);
    459 		return;
    460 	}
    461 #endif
    462 
    463 	/*
    464 	 * Some lance device does not present IFF_SIMPLEX behavior on multicast
    465 	 * packets.  Make sure to drop it if it is from ourselves.
    466 	 */
    467 	if (!ETHER_CMP(eh->ether_shost, sc->sc_enaddr)) {
    468 		m_freem(m);
    469 		return;
    470 	}
    471 
    472 	/* Pass the packet up. */
    473 	if_percpuq_enqueue(ifp->if_percpuq, m);
    474 }
    475 
    476 #undef	ifp
    477 
    478 void
    479 lance_watchdog(struct ifnet *ifp)
    480 {
    481 	struct lance_softc *sc = ifp->if_softc;
    482 
    483 	log(LOG_ERR, "%s: device timeout\n", device_xname(sc->sc_dev));
    484 	if_statinc(ifp, if_oerrors);
    485 
    486 	lance_reset(sc);
    487 }
    488 
    489 int
    490 lance_mediachange(struct ifnet *ifp)
    491 {
    492 	struct lance_softc *sc = ifp->if_softc;
    493 
    494 	if (sc->sc_mediachange)
    495 		return ((*sc->sc_mediachange)(sc));
    496 	return (0);
    497 }
    498 
    499 void
    500 lance_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
    501 {
    502 	struct lance_softc *sc = ifp->if_softc;
    503 
    504 	if ((ifp->if_flags & IFF_UP) == 0)
    505 		return;
    506 
    507 	ifmr->ifm_status = IFM_AVALID;
    508 	if (sc->sc_havecarrier)
    509 		ifmr->ifm_status |= IFM_ACTIVE;
    510 
    511 	if (sc->sc_mediastatus)
    512 		(*sc->sc_mediastatus)(sc, ifmr);
    513 }
    514 
    515 /*
    516  * Process an ioctl request.
    517  */
    518 int
    519 lance_ioctl(struct ifnet *ifp, u_long cmd, void *data)
    520 {
    521 	struct lance_softc *sc = ifp->if_softc;
    522 	int s, error = 0;
    523 
    524 	s = splnet();
    525 
    526 	switch (cmd) {
    527 	default:
    528 		if ((error = ether_ioctl(ifp, cmd, data)) != ENETRESET)
    529 			break;
    530 		error = 0;
    531 		if (cmd != SIOCADDMULTI && cmd != SIOCDELMULTI)
    532 			break;
    533 		if (ifp->if_flags & IFF_RUNNING) {
    534 			/*
    535 			 * Multicast list has changed; set the hardware filter
    536 			 * accordingly.
    537 			 */
    538 			lance_reset(sc);
    539 		}
    540 		break;
    541 
    542 	}
    543 
    544 	splx(s);
    545 	return (error);
    546 }
    547 
    548 hide bool
    549 lance_shutdown(device_t self, int howto)
    550 {
    551 	struct lance_softc *sc = device_private(self);
    552 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
    553 
    554 	lance_stop(ifp, 0);
    555 
    556 	return true;
    557 }
    558 
    559 /*
    560  * Set up the logical address filter.
    561  */
    562 void
    563 lance_setladrf(struct ethercom *ec, uint16_t *af)
    564 {
    565 	struct ifnet *ifp = &ec->ec_if;
    566 	struct ether_multi *enm;
    567 	uint32_t crc;
    568 	struct ether_multistep step;
    569 
    570 	/*
    571 	 * Set up multicast address filter by passing all multicast addresses
    572 	 * through a crc generator, and then using the high order 6 bits as an
    573 	 * index into the 64 bit logical address filter.  The high order bit
    574 	 * selects the word, while the rest of the bits select the bit within
    575 	 * the word.
    576 	 */
    577 
    578 	if (ifp->if_flags & IFF_PROMISC)
    579 		goto allmulti;
    580 
    581 	af[0] = af[1] = af[2] = af[3] = 0x0000;
    582 
    583 	ETHER_LOCK(ec);
    584 	ETHER_FIRST_MULTI(step, ec, enm);
    585 	while (enm != NULL) {
    586 		if (ETHER_CMP(enm->enm_addrlo, enm->enm_addrhi)) {
    587 			/*
    588 			 * We must listen to a range of multicast addresses.
    589 			 * For now, just accept all multicasts, rather than
    590 			 * trying to set only those filter bits needed to match
    591 			 * the range.  (At this time, the only use of address
    592 			 * ranges is for IP multicast routing, for which the
    593 			 * range is big enough to require all bits set.)
    594 			 */
    595 			ETHER_UNLOCK(ec);
    596 			goto allmulti;
    597 		}
    598 
    599 		crc = ether_crc32_le(enm->enm_addrlo, ETHER_ADDR_LEN);
    600 
    601 		/* Just want the 6 most significant bits. */
    602 		crc >>= 26;
    603 
    604 		/* Set the corresponding bit in the filter. */
    605 		af[crc >> 4] |= 1 << (crc & 0xf);
    606 
    607 		ETHER_NEXT_MULTI(step, enm);
    608 	}
    609 	ETHER_UNLOCK(ec);
    610 	ifp->if_flags &= ~IFF_ALLMULTI;
    611 	return;
    612 
    613 allmulti:
    614 	ifp->if_flags |= IFF_ALLMULTI;
    615 	af[0] = af[1] = af[2] = af[3] = 0xffff;
    616 }
    617 
    618 /*
    619  * Routines for accessing the transmit and receive buffers.
    620  * The various CPU and adapter configurations supported by this
    621  * driver require three different access methods for buffers
    622  * and descriptors:
    623  *	(1) contig (contiguous data; no padding),
    624  *	(2) gap2 (two bytes of data followed by two bytes of padding),
    625  *	(3) gap16 (16 bytes of data followed by 16 bytes of padding).
    626  */
    627 
    628 /*
    629  * contig: contiguous data with no padding.
    630  *
    631  * Buffers may have any alignment.
    632  */
    633 
    634 void
    635 lance_copytobuf_contig(struct lance_softc *sc, void *from, int boff, int len)
    636 {
    637 	uint8_t *buf = sc->sc_mem;
    638 
    639 	/*
    640 	 * Just call memcpy() to do the work.
    641 	 */
    642 	memcpy(buf + boff, from, len);
    643 }
    644 
    645 void
    646 lance_copyfrombuf_contig(struct lance_softc *sc, void *to, int boff, int len)
    647 {
    648 	uint8_t *buf = sc->sc_mem;
    649 
    650 	/*
    651 	 * Just call memcpy() to do the work.
    652 	 */
    653 	memcpy(to, buf + boff, len);
    654 }
    655 
    656 void
    657 lance_zerobuf_contig(struct lance_softc *sc, int boff, int len)
    658 {
    659 	uint8_t *buf = sc->sc_mem;
    660 
    661 	/*
    662 	 * Just let memset() do the work
    663 	 */
    664 	memset(buf + boff, 0, len);
    665 }
    666 
    667 #if 0
    668 /*
    669  * Examples only; duplicate these and tweak (if necessary) in
    670  * machine-specific front-ends.
    671  */
    672 
    673 /*
    674  * gap2: two bytes of data followed by two bytes of pad.
    675  *
    676  * Buffers must be 4-byte aligned.  The code doesn't worry about
    677  * doing an extra byte.
    678  */
    679 
    680 void
    681 lance_copytobuf_gap2(struct lance_softc *sc, void *fromv, int boff, int len)
    682 {
    683 	volatile void *buf = sc->sc_mem;
    684 	void *from = fromv;
    685 	volatile uint16_t *bptr;
    686 
    687 	if (boff & 0x1) {
    688 		/* handle unaligned first byte */
    689 		bptr = ((volatile uint16_t *)buf) + (boff - 1);
    690 		*bptr = (*from++ << 8) | (*bptr & 0xff);
    691 		bptr += 2;
    692 		len--;
    693 	} else
    694 		bptr = ((volatile uint16_t *)buf) + boff;
    695 	while (len > 1) {
    696 		*bptr = (from[1] << 8) | (from[0] & 0xff);
    697 		bptr += 2;
    698 		from += 2;
    699 		len -= 2;
    700 	}
    701 	if (len == 1)
    702 		*bptr = (uint16_t)*from;
    703 }
    704 
    705 void
    706 lance_copyfrombuf_gap2(struct lance_softc *sc, void *tov, int boff, int len)
    707 {
    708 	volatile void *buf = sc->sc_mem;
    709 	void *to = tov;
    710 	volatile uint16_t *bptr;
    711 	uint16_t tmp;
    712 
    713 	if (boff & 0x1) {
    714 		/* handle unaligned first byte */
    715 		bptr = ((volatile uint16_t *)buf) + (boff - 1);
    716 		*to++ = (*bptr >> 8) & 0xff;
    717 		bptr += 2;
    718 		len--;
    719 	} else
    720 		bptr = ((volatile uint16_t *)buf) + boff;
    721 	while (len > 1) {
    722 		tmp = *bptr;
    723 		*to++ = tmp & 0xff;
    724 		*to++ = (tmp >> 8) & 0xff;
    725 		bptr += 2;
    726 		len -= 2;
    727 	}
    728 	if (len == 1)
    729 		*to = *bptr & 0xff;
    730 }
    731 
    732 void
    733 lance_zerobuf_gap2(struct lance_softc *sc, int boff, int len)
    734 {
    735 	volatile void *buf = sc->sc_mem;
    736 	volatile uint16_t *bptr;
    737 
    738 	if ((unsigned int)boff & 0x1) {
    739 		bptr = ((volatile uint16_t *)buf) + (boff - 1);
    740 		*bptr &= 0xff;
    741 		bptr += 2;
    742 		len--;
    743 	} else
    744 		bptr = ((volatile uint16_t *)buf) + boff;
    745 	while (len > 0) {
    746 		*bptr = 0;
    747 		bptr += 2;
    748 		len -= 2;
    749 	}
    750 }
    751 
    752 /*
    753  * gap16: 16 bytes of data followed by 16 bytes of pad.
    754  *
    755  * Buffers must be 32-byte aligned.
    756  */
    757 
    758 void
    759 lance_copytobuf_gap16(struct lance_softc *sc, void *fromv, int boff, int len)
    760 {
    761 	volatile uint8_t *buf = sc->sc_mem;
    762 	void *from = fromv;
    763 	uint8_t *bptr;
    764 	int xfer;
    765 
    766 	bptr = buf + ((boff << 1) & ~0x1f);
    767 	boff &= 0xf;
    768 	xfer = uimin(len, 16 - boff);
    769 	while (len > 0) {
    770 		memcpy(bptr + boff, from, xfer);
    771 		from += xfer;
    772 		bptr += 32;
    773 		boff = 0;
    774 		len -= xfer;
    775 		xfer = uimin(len, 16);
    776 	}
    777 }
    778 
    779 void
    780 lance_copyfrombuf_gap16(struct lance_softc *sc, void *tov, int boff, int len)
    781 {
    782 	volatile uint8_t *buf = sc->sc_mem;
    783 	void *to = tov;
    784 	uint8_t *bptr;
    785 	int xfer;
    786 
    787 	bptr = buf + ((boff << 1) & ~0x1f);
    788 	boff &= 0xf;
    789 	xfer = uimin(len, 16 - boff);
    790 	while (len > 0) {
    791 		memcpy(to, bptr + boff, xfer);
    792 		to += xfer;
    793 		bptr += 32;
    794 		boff = 0;
    795 		len -= xfer;
    796 		xfer = uimin(len, 16);
    797 	}
    798 }
    799 
    800 void
    801 lance_zerobuf_gap16(struct lance_softc *sc, int boff, int len)
    802 {
    803 	volatile uint8_t *buf = sc->sc_mem;
    804 	uint8_t *bptr;
    805 	int xfer;
    806 
    807 	bptr = buf + ((boff << 1) & ~0x1f);
    808 	boff &= 0xf;
    809 	xfer = uimin(len, 16 - boff);
    810 	while (len > 0) {
    811 		memset(bptr + boff, 0, xfer);
    812 		bptr += 32;
    813 		boff = 0;
    814 		len -= xfer;
    815 		xfer = uimin(len, 16);
    816 	}
    817 }
    818 #endif /* Example only */
    819