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am7990.c revision 1.26
      1 /*	$NetBSD: am7990.c,v 1.26 1997/03/15 18:11:25 is Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1995 Charles M. Hannum.  All rights reserved.
      5  * Copyright (c) 1992, 1993
      6  *	The Regents of the University of California.  All rights reserved.
      7  *
      8  * This code is derived from software contributed to Berkeley by
      9  * Ralph Campbell and Rick Macklem.
     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  * 3. All advertising materials mentioning features or use of this software
     20  *    must display the following acknowledgement:
     21  *	This product includes software developed by the University of
     22  *	California, Berkeley and its contributors.
     23  * 4. Neither the name of the University nor the names of its contributors
     24  *    may be used to endorse or promote products derived from this software
     25  *    without specific prior written permission.
     26  *
     27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     37  * SUCH DAMAGE.
     38  *
     39  *	@(#)if_le.c	8.2 (Berkeley) 11/16/93
     40  */
     41 
     42 #include "bpfilter.h"
     43 
     44 #include <sys/param.h>
     45 #include <sys/systm.h>
     46 #include <sys/mbuf.h>
     47 #include <sys/syslog.h>
     48 #include <sys/socket.h>
     49 #include <sys/device.h>
     50 #include <sys/malloc.h>
     51 #include <sys/ioctl.h>
     52 #include <sys/errno.h>
     53 
     54 #include <net/if.h>
     55 #include <net/if_dl.h>
     56 #include <net/if_ether.h>
     57 
     58 #ifdef INET
     59 #include <netinet/in.h>
     60 #include <netinet/if_inarp.h>
     61 #include <netinet/in_systm.h>
     62 #include <netinet/in_var.h>
     63 #include <netinet/ip.h>
     64 #endif
     65 
     66 #ifdef NS
     67 #include <netns/ns.h>
     68 #include <netns/ns_if.h>
     69 #endif
     70 
     71 #if defined(CCITT) && defined(LLC)
     72 #include <sys/socketvar.h>
     73 #include <netccitt/x25.h>
     74 #include <netccitt/pk.h>
     75 #include <netccitt/pk_var.h>
     76 #include <netccitt/pk_extern.h>
     77 #endif
     78 
     79 #if NBPFILTER > 0
     80 #include <net/bpf.h>
     81 #include <net/bpfdesc.h>
     82 #endif
     83 
     84 #include <dev/ic/am7990reg.h>
     85 #include <dev/ic/am7990var.h>
     86 
     87 #ifdef LEDEBUG
     88 void am7990_recv_print __P((struct am7990_softc *, int));
     89 void am7990_xmit_print __P((struct am7990_softc *, int));
     90 #endif
     91 
     92 integrate void am7990_rint __P((struct am7990_softc *));
     93 integrate void am7990_tint __P((struct am7990_softc *));
     94 
     95 integrate int am7990_put __P((struct am7990_softc *, int, struct mbuf *));
     96 integrate struct mbuf *am7990_get __P((struct am7990_softc *, int, int));
     97 integrate void am7990_read __P((struct am7990_softc *, int, int));
     98 
     99 hide void am7990_shutdown __P((void *));
    100 
    101 #define	ifp	(&sc->sc_ethercom.ec_if)
    102 
    103 #ifdef	sun3	/* XXX what do we do about this?!  --thorpej */
    104 static inline u_int16_t ether_cmp __P((void *, void *));
    105 
    106 /*
    107  * Compare two Ether/802 addresses for equality, inlined and
    108  * unrolled for speed.  I'd love to have an inline assembler
    109  * version of this...   XXX: Who wanted that? mycroft?
    110  * I wrote one, but the following is just as efficient.
    111  * This expands to 10 short m68k instructions! -gwr
    112  * Note: use this like bcmp()
    113  */
    114 static inline u_short
    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 	diff  = *a++ - *b++;
    123 	diff |= *a++ - *b++;
    124 	diff |= *a++ - *b++;
    125 
    126 	return (diff);
    127 }
    128 
    129 #define ETHER_CMP	ether_cmp
    130 #endif /* XXX */
    131 
    132 #ifndef	ETHER_CMP
    133 #define	ETHER_CMP(a, b) bcmp((a), (b), ETHER_ADDR_LEN)
    134 #endif
    135 
    136 /*
    137  * am7990 configuration driver.  Attachments are provided by
    138  * machine-dependent driver front-ends.
    139  */
    140 struct cfdriver le_cd = {
    141 	NULL, "le", DV_IFNET
    142 };
    143 
    144 void
    145 am7990_config(sc)
    146 	struct am7990_softc *sc;
    147 {
    148 	int mem, i;
    149 
    150 	/* Make sure the chip is stopped. */
    151 	am7990_stop(sc);
    152 
    153 	/* Initialize ifnet structure. */
    154 	bcopy(sc->sc_dev.dv_xname, ifp->if_xname, IFNAMSIZ);
    155 	ifp->if_softc = sc;
    156 	ifp->if_start = am7990_start;
    157 	ifp->if_ioctl = am7990_ioctl;
    158 	ifp->if_watchdog = am7990_watchdog;
    159 	ifp->if_flags =
    160 	    IFF_BROADCAST | IFF_SIMPLEX | IFF_NOTRAILERS | IFF_MULTICAST;
    161 #ifdef LANCE_REVC_BUG
    162 	ifp->if_flags &= ~IFF_MULTICAST;
    163 #endif
    164 
    165 	/* Attach the interface. */
    166 	if_attach(ifp);
    167 	ether_ifattach(ifp, sc->sc_enaddr);
    168 
    169 #if NBPFILTER > 0
    170 	bpfattach(&ifp->if_bpf, ifp, DLT_EN10MB, sizeof(struct ether_header));
    171 #endif
    172 
    173 	switch (sc->sc_memsize) {
    174 	case 8192:
    175 		sc->sc_nrbuf = 4;
    176 		sc->sc_ntbuf = 1;
    177 		break;
    178 	case 16384:
    179 		sc->sc_nrbuf = 8;
    180 		sc->sc_ntbuf = 2;
    181 		break;
    182 	case 32768:
    183 		sc->sc_nrbuf = 16;
    184 		sc->sc_ntbuf = 4;
    185 		break;
    186 	case 65536:
    187 		sc->sc_nrbuf = 32;
    188 		sc->sc_ntbuf = 8;
    189 		break;
    190 	case 131072:
    191 		sc->sc_nrbuf = 64;
    192 		sc->sc_ntbuf = 16;
    193 		break;
    194 	default:
    195 		panic("am7990_config: weird memory size");
    196 	}
    197 
    198 	printf(": address %s\n", ether_sprintf(sc->sc_enaddr));
    199 	printf("%s: %d receive buffers, %d transmit buffers\n",
    200 	    sc->sc_dev.dv_xname, sc->sc_nrbuf, sc->sc_ntbuf);
    201 
    202 	sc->sc_sh = shutdownhook_establish(am7990_shutdown, sc);
    203 	if (sc->sc_sh == NULL)
    204 		panic("am7990_config: can't establish shutdownhook");
    205 	sc->sc_rbufaddr = malloc(sc->sc_nrbuf * sizeof(int), M_DEVBUF,
    206 					M_WAITOK);
    207 	sc->sc_tbufaddr = malloc(sc->sc_ntbuf * sizeof(int), M_DEVBUF,
    208 					M_WAITOK);
    209 
    210 	mem = 0;
    211 	sc->sc_initaddr = mem;
    212 	mem += sizeof(struct leinit);
    213 	sc->sc_rmdaddr = mem;
    214 	mem += sizeof(struct lermd) * sc->sc_nrbuf;
    215 	sc->sc_tmdaddr = mem;
    216 	mem += sizeof(struct letmd) * sc->sc_ntbuf;
    217 	for (i = 0; i < sc->sc_nrbuf; i++, mem += LEBLEN)
    218 		sc->sc_rbufaddr[i] = mem;
    219 	for (i = 0; i < sc->sc_ntbuf; i++, mem += LEBLEN)
    220 		sc->sc_tbufaddr[i] = mem;
    221 #ifdef notyet
    222 	if (mem > ...)
    223 		panic(...);
    224 #endif
    225 }
    226 
    227 void
    228 am7990_reset(sc)
    229 	struct am7990_softc *sc;
    230 {
    231 	int s;
    232 
    233 	s = splimp();
    234 	am7990_init(sc);
    235 	splx(s);
    236 }
    237 
    238 /*
    239  * Set up the initialization block and the descriptor rings.
    240  */
    241 void
    242 am7990_meminit(sc)
    243 	register struct am7990_softc *sc;
    244 {
    245 	u_long a;
    246 	int bix;
    247 	struct leinit init;
    248 	struct lermd rmd;
    249 	struct letmd tmd;
    250 
    251 #if NBPFILTER > 0
    252 	if (ifp->if_flags & IFF_PROMISC)
    253 		init.init_mode = LE_MODE_NORMAL | LE_MODE_PROM;
    254 	else
    255 #endif
    256 		init.init_mode = LE_MODE_NORMAL;
    257 	init.init_padr[0] =
    258 	    (LLADDR(ifp->if_sadl)[1] << 8) | LLADDR(ifp->if_sadl)[0];
    259 	init.init_padr[1] =
    260 	    (LLADDR(ifp->if_sadl)[3] << 8) | LLADDR(ifp->if_sadl)[2];
    261 	init.init_padr[2] =
    262 	    (LLADDR(ifp->if_sadl)[5] << 8) | LLADDR(ifp->if_sadl)[4];
    263 	am7990_setladrf(&sc->sc_ethercom, init.init_ladrf);
    264 
    265 	sc->sc_last_rd = 0;
    266 	sc->sc_first_td = sc->sc_last_td = sc->sc_no_td = 0;
    267 
    268 	a = sc->sc_addr + LE_RMDADDR(sc, 0);
    269 	init.init_rdra = a;
    270 	init.init_rlen = (a >> 16) | ((ffs(sc->sc_nrbuf) - 1) << 13);
    271 
    272 	a = sc->sc_addr + LE_TMDADDR(sc, 0);
    273 	init.init_tdra = a;
    274 	init.init_tlen = (a >> 16) | ((ffs(sc->sc_ntbuf) - 1) << 13);
    275 
    276 	(*sc->sc_copytodesc)(sc, &init, LE_INITADDR(sc), sizeof(init));
    277 
    278 	/*
    279 	 * Set up receive ring descriptors.
    280 	 */
    281 	for (bix = 0; bix < sc->sc_nrbuf; bix++) {
    282 		a = sc->sc_addr + LE_RBUFADDR(sc, bix);
    283 		rmd.rmd0 = a;
    284 		rmd.rmd1_hadr = a >> 16;
    285 		rmd.rmd1_bits = LE_R1_OWN;
    286 		rmd.rmd2 = -LEBLEN | LE_XMD2_ONES;
    287 		rmd.rmd3 = 0;
    288 		(*sc->sc_copytodesc)(sc, &rmd, LE_RMDADDR(sc, bix),
    289 		    sizeof(rmd));
    290 	}
    291 
    292 	/*
    293 	 * Set up transmit ring descriptors.
    294 	 */
    295 	for (bix = 0; bix < sc->sc_ntbuf; bix++) {
    296 		a = sc->sc_addr + LE_TBUFADDR(sc, bix);
    297 		tmd.tmd0 = a;
    298 		tmd.tmd1_hadr = a >> 16;
    299 		tmd.tmd1_bits = 0;
    300 		tmd.tmd2 = 0 | LE_XMD2_ONES;
    301 		tmd.tmd3 = 0;
    302 		(*sc->sc_copytodesc)(sc, &tmd, LE_TMDADDR(sc, bix),
    303 		    sizeof(tmd));
    304 	}
    305 }
    306 
    307 void
    308 am7990_stop(sc)
    309 	struct am7990_softc *sc;
    310 {
    311 
    312 	(*sc->sc_wrcsr)(sc, LE_CSR0, LE_C0_STOP);
    313 }
    314 
    315 /*
    316  * Initialization of interface; set up initialization block
    317  * and transmit/receive descriptor rings.
    318  */
    319 void
    320 am7990_init(sc)
    321 	register struct am7990_softc *sc;
    322 {
    323 	register int timo;
    324 	u_long a;
    325 
    326 	(*sc->sc_wrcsr)(sc, LE_CSR0, LE_C0_STOP);
    327 	DELAY(100);
    328 
    329 	/* Set the correct byte swapping mode, etc. */
    330 	(*sc->sc_wrcsr)(sc, LE_CSR3, sc->sc_conf3);
    331 
    332 	/* Set up LANCE init block. */
    333 	am7990_meminit(sc);
    334 
    335 	/* Give LANCE the physical address of its init block. */
    336 	a = sc->sc_addr + LE_INITADDR(sc);
    337 	(*sc->sc_wrcsr)(sc, LE_CSR1, a);
    338 	(*sc->sc_wrcsr)(sc, LE_CSR2, a >> 16);
    339 
    340 	/* Try to initialize the LANCE. */
    341 	DELAY(100);
    342 	(*sc->sc_wrcsr)(sc, LE_CSR0, LE_C0_INIT);
    343 
    344 	/* Wait for initialization to finish. */
    345 	for (timo = 100000; timo; timo--)
    346 		if ((*sc->sc_rdcsr)(sc, LE_CSR0) & LE_C0_IDON)
    347 			break;
    348 
    349 	if ((*sc->sc_rdcsr)(sc, LE_CSR0) & LE_C0_IDON) {
    350 		/* Start the LANCE. */
    351 		(*sc->sc_wrcsr)(sc, LE_CSR0, LE_C0_INEA | LE_C0_STRT |
    352 		    LE_C0_IDON);
    353 		ifp->if_flags |= IFF_RUNNING;
    354 		ifp->if_flags &= ~IFF_OACTIVE;
    355 		ifp->if_timer = 0;
    356 		am7990_start(ifp);
    357 	} else
    358 		printf("%s: card failed to initialize\n", sc->sc_dev.dv_xname);
    359 	if (sc->sc_hwinit)
    360 		(*sc->sc_hwinit)(sc);
    361 }
    362 
    363 /*
    364  * Routine to copy from mbuf chain to transmit buffer in
    365  * network buffer memory.
    366  */
    367 integrate int
    368 am7990_put(sc, boff, m)
    369 	struct am7990_softc *sc;
    370 	int boff;
    371 	register struct mbuf *m;
    372 {
    373 	register struct mbuf *n;
    374 	register int len, tlen = 0;
    375 
    376 	for (; m; m = n) {
    377 		len = m->m_len;
    378 		if (len == 0) {
    379 			MFREE(m, n);
    380 			continue;
    381 		}
    382 		(*sc->sc_copytobuf)(sc, mtod(m, caddr_t), boff, len);
    383 		boff += len;
    384 		tlen += len;
    385 		MFREE(m, n);
    386 	}
    387 	if (tlen < LEMINSIZE) {
    388 		(*sc->sc_zerobuf)(sc, boff, LEMINSIZE - tlen);
    389 		tlen = LEMINSIZE;
    390 	}
    391 	return (tlen);
    392 }
    393 
    394 /*
    395  * Pull data off an interface.
    396  * Len is length of data, with local net header stripped.
    397  * We copy the data into mbufs.  When full cluster sized units are present
    398  * we copy into clusters.
    399  */
    400 integrate struct mbuf *
    401 am7990_get(sc, boff, totlen)
    402 	struct am7990_softc *sc;
    403 	int boff, totlen;
    404 {
    405 	register struct mbuf *m;
    406 	struct mbuf *top, **mp;
    407 	int len, pad;
    408 
    409 	MGETHDR(m, M_DONTWAIT, MT_DATA);
    410 	if (m == 0)
    411 		return (0);
    412 	m->m_pkthdr.rcvif = ifp;
    413 	m->m_pkthdr.len = totlen;
    414 	pad = ALIGN(sizeof(struct ether_header)) - sizeof(struct ether_header);
    415 	m->m_data += pad;
    416 	len = MHLEN - pad;
    417 	top = 0;
    418 	mp = &top;
    419 
    420 	while (totlen > 0) {
    421 		if (top) {
    422 			MGET(m, M_DONTWAIT, MT_DATA);
    423 			if (m == 0) {
    424 				m_freem(top);
    425 				return 0;
    426 			}
    427 			len = MLEN;
    428 		}
    429 		if (top && totlen >= MINCLSIZE) {
    430 			MCLGET(m, M_DONTWAIT);
    431 			if (m->m_flags & M_EXT)
    432 				len = MCLBYTES;
    433 		}
    434 		m->m_len = len = min(totlen, len);
    435 		(*sc->sc_copyfrombuf)(sc, mtod(m, caddr_t), boff, len);
    436 		boff += len;
    437 		totlen -= len;
    438 		*mp = m;
    439 		mp = &m->m_next;
    440 	}
    441 
    442 	return (top);
    443 }
    444 
    445 /*
    446  * Pass a packet to the higher levels.
    447  */
    448 integrate void
    449 am7990_read(sc, boff, len)
    450 	register struct am7990_softc *sc;
    451 	int boff, len;
    452 {
    453 	struct mbuf *m;
    454 	struct ether_header *eh;
    455 
    456 	if (len <= sizeof(struct ether_header) ||
    457 	    len > ETHERMTU + sizeof(struct ether_header)) {
    458 #ifdef LEDEBUG
    459 		printf("%s: invalid packet size %d; dropping\n",
    460 		    sc->sc_dev.dv_xname, len);
    461 #endif
    462 		ifp->if_ierrors++;
    463 		return;
    464 	}
    465 
    466 	/* Pull packet off interface. */
    467 	m = am7990_get(sc, boff, len);
    468 	if (m == 0) {
    469 		ifp->if_ierrors++;
    470 		return;
    471 	}
    472 
    473 	ifp->if_ipackets++;
    474 
    475 	/* We assume that the header fit entirely in one mbuf. */
    476 	eh = mtod(m, struct ether_header *);
    477 
    478 #if NBPFILTER > 0
    479 	/*
    480 	 * Check if there's a BPF listener on this interface.
    481 	 * If so, hand off the raw packet to BPF.
    482 	 */
    483 	if (ifp->if_bpf) {
    484 		bpf_mtap(ifp->if_bpf, m);
    485 
    486 #ifndef LANCE_REVC_BUG
    487 		/*
    488 		 * Note that the interface cannot be in promiscuous mode if
    489 		 * there are no BPF listeners.  And if we are in promiscuous
    490 		 * mode, we have to check if this packet is really ours.
    491 		 */
    492 		if ((ifp->if_flags & IFF_PROMISC) != 0 &&
    493 		    (eh->ether_dhost[0] & 1) == 0 && /* !mcast and !bcast */
    494 		    ETHER_CMP(eh->ether_dhost, LLADDR(ifp->if_sadl))) {
    495 			m_freem(m);
    496 			return;
    497 		}
    498 #endif
    499 	}
    500 #endif
    501 
    502 #ifdef LANCE_REVC_BUG
    503 	/*
    504 	 * The old LANCE (Rev. C) chips have a bug which causes
    505 	 * garbage to be inserted in front of the received packet.
    506 	 * The work-around is to ignore packets with an invalid
    507 	 * destination address (garbage will usually not match).
    508 	 * Of course, this precludes multicast support...
    509 	 */
    510 	if (ETHER_CMP(eh->ether_dhost, LLADDR(ifp->if_sadl)) &&
    511 	    ETHER_CMP(eh->ether_dhost, etherbroadcastaddr)) {
    512 		m_freem(m);
    513 		return;
    514 	}
    515 #endif
    516 
    517 	/* Pass the packet up, with the ether header sort-of removed. */
    518 	m_adj(m, sizeof(struct ether_header));
    519 	ether_input(ifp, eh, m);
    520 }
    521 
    522 integrate void
    523 am7990_rint(sc)
    524 	struct am7990_softc *sc;
    525 {
    526 	register int bix;
    527 	int rp;
    528 	struct lermd rmd;
    529 
    530 	bix = sc->sc_last_rd;
    531 
    532 	/* Process all buffers with valid data. */
    533 	for (;;) {
    534 		rp = LE_RMDADDR(sc, bix);
    535 		(*sc->sc_copyfromdesc)(sc, &rmd, rp, sizeof(rmd));
    536 
    537 		if (rmd.rmd1_bits & LE_R1_OWN)
    538 			break;
    539 
    540 		if (rmd.rmd1_bits & LE_R1_ERR) {
    541 			if (rmd.rmd1_bits & LE_R1_ENP) {
    542 #ifdef LEDEBUG
    543 				if ((rmd.rmd1_bits & LE_R1_OFLO) == 0) {
    544 					if (rmd.rmd1_bits & LE_R1_FRAM)
    545 						printf("%s: framing error\n",
    546 						    sc->sc_dev.dv_xname);
    547 					if (rmd.rmd1_bits & LE_R1_CRC)
    548 						printf("%s: crc mismatch\n",
    549 						    sc->sc_dev.dv_xname);
    550 				}
    551 #endif
    552 			} else {
    553 				if (rmd.rmd1_bits & LE_R1_OFLO)
    554 					printf("%s: overflow\n",
    555 					    sc->sc_dev.dv_xname);
    556 			}
    557 			if (rmd.rmd1_bits & LE_R1_BUFF)
    558 				printf("%s: receive buffer error\n",
    559 				    sc->sc_dev.dv_xname);
    560 			ifp->if_ierrors++;
    561 		} else if ((rmd.rmd1_bits & (LE_R1_STP | LE_R1_ENP)) !=
    562 		    (LE_R1_STP | LE_R1_ENP)) {
    563 			printf("%s: dropping chained buffer\n",
    564 			    sc->sc_dev.dv_xname);
    565 			ifp->if_ierrors++;
    566 		} else {
    567 #ifdef LEDEBUG
    568 			if (sc->sc_debug)
    569 				am7990_recv_print(sc, sc->sc_last_rd);
    570 #endif
    571 			am7990_read(sc, LE_RBUFADDR(sc, bix),
    572 			    (int)rmd.rmd3 - 4);
    573 		}
    574 
    575 		rmd.rmd1_bits = LE_R1_OWN;
    576 		rmd.rmd2 = -LEBLEN | LE_XMD2_ONES;
    577 		rmd.rmd3 = 0;
    578 		(*sc->sc_copytodesc)(sc, &rmd, rp, sizeof(rmd));
    579 
    580 #ifdef LEDEBUG
    581 		if (sc->sc_debug)
    582 			printf("sc->sc_last_rd = %x, rmd: "
    583 			       "ladr %04x, hadr %02x, flags %02x, "
    584 			       "bcnt %04x, mcnt %04x\n",
    585 				sc->sc_last_rd,
    586 				rmd.rmd0, rmd.rmd1_hadr, rmd.rmd1_bits,
    587 				rmd.rmd2, rmd.rmd3);
    588 #endif
    589 
    590 		if (++bix == sc->sc_nrbuf)
    591 			bix = 0;
    592 	}
    593 
    594 	sc->sc_last_rd = bix;
    595 }
    596 
    597 integrate void
    598 am7990_tint(sc)
    599 	register struct am7990_softc *sc;
    600 {
    601 	register int bix;
    602 	struct letmd tmd;
    603 
    604 	bix = sc->sc_first_td;
    605 
    606 	for (;;) {
    607 		if (sc->sc_no_td <= 0)
    608 			break;
    609 
    610 #ifdef LEDEBUG
    611 		if (sc->sc_debug)
    612 			printf("trans tmd: "
    613 			    "ladr %04x, hadr %02x, flags %02x, "
    614 			    "bcnt %04x, mcnt %04x\n",
    615 			    tmd.tmd0, tmd.tmd1_hadr, tmd.tmd1_bits,
    616 			    tmd.tmd2, tmd.tmd3);
    617 #endif
    618 
    619 		(*sc->sc_copyfromdesc)(sc, &tmd, LE_TMDADDR(sc, bix),
    620 		    sizeof(tmd));
    621 
    622 		if (tmd.tmd1_bits & LE_T1_OWN)
    623 			break;
    624 
    625 		ifp->if_flags &= ~IFF_OACTIVE;
    626 
    627 		if (tmd.tmd1_bits & LE_T1_ERR) {
    628 			if (tmd.tmd3 & LE_T3_BUFF)
    629 				printf("%s: transmit buffer error\n",
    630 				    sc->sc_dev.dv_xname);
    631 			else if (tmd.tmd3 & LE_T3_UFLO)
    632 				printf("%s: underflow\n", sc->sc_dev.dv_xname);
    633 			if (tmd.tmd3 & (LE_T3_BUFF | LE_T3_UFLO)) {
    634 				am7990_reset(sc);
    635 				return;
    636 			}
    637 			if (tmd.tmd3 & LE_T3_LCAR) {
    638 				if (sc->sc_nocarrier)
    639 					(*sc->sc_nocarrier)(sc);
    640 				else
    641 					printf("%s: lost carrier\n",
    642 					    sc->sc_dev.dv_xname);
    643 			}
    644 			if (tmd.tmd3 & LE_T3_LCOL)
    645 				ifp->if_collisions++;
    646 			if (tmd.tmd3 & LE_T3_RTRY) {
    647 				printf("%s: excessive collisions, tdr %d\n",
    648 				    sc->sc_dev.dv_xname,
    649 				    tmd.tmd3 & LE_T3_TDR_MASK);
    650 				ifp->if_collisions += 16;
    651 			}
    652 			ifp->if_oerrors++;
    653 		} else {
    654 			if (tmd.tmd1_bits & LE_T1_ONE)
    655 				ifp->if_collisions++;
    656 			else if (tmd.tmd1_bits & LE_T1_MORE)
    657 				/* Real number is unknown. */
    658 				ifp->if_collisions += 2;
    659 			ifp->if_opackets++;
    660 		}
    661 
    662 		if (++bix == sc->sc_ntbuf)
    663 			bix = 0;
    664 
    665 		--sc->sc_no_td;
    666 	}
    667 
    668 	sc->sc_first_td = bix;
    669 
    670 	am7990_start(ifp);
    671 
    672 	if (sc->sc_no_td == 0)
    673 		ifp->if_timer = 0;
    674 }
    675 
    676 /*
    677  * Controller interrupt.
    678  */
    679 int
    680 am7990_intr(arg)
    681 	register void *arg;
    682 {
    683 	register struct am7990_softc *sc = arg;
    684 	register u_int16_t isr;
    685 
    686 	isr = (*sc->sc_rdcsr)(sc, LE_CSR0) | sc->sc_saved_csr0;
    687 	sc->sc_saved_csr0 = 0;
    688 #ifdef LEDEBUG
    689 	if (sc->sc_debug)
    690 		printf("%s: am7990_intr entering with isr=%04x\n",
    691 		    sc->sc_dev.dv_xname, isr);
    692 #endif
    693 	if ((isr & LE_C0_INTR) == 0)
    694 		return (0);
    695 
    696 	(*sc->sc_wrcsr)(sc, LE_CSR0,
    697 	    isr & (LE_C0_INEA | LE_C0_BABL | LE_C0_MISS | LE_C0_MERR |
    698 		   LE_C0_RINT | LE_C0_TINT | LE_C0_IDON));
    699 	if (isr & LE_C0_ERR) {
    700 		if (isr & LE_C0_BABL) {
    701 #ifdef LEDEBUG
    702 			printf("%s: babble\n", sc->sc_dev.dv_xname);
    703 #endif
    704 			ifp->if_oerrors++;
    705 		}
    706 #if 0
    707 		if (isr & LE_C0_CERR) {
    708 			printf("%s: collision error\n", sc->sc_dev.dv_xname);
    709 			ifp->if_collisions++;
    710 		}
    711 #endif
    712 		if (isr & LE_C0_MISS) {
    713 #ifdef LEDEBUG
    714 			printf("%s: missed packet\n", sc->sc_dev.dv_xname);
    715 #endif
    716 			ifp->if_ierrors++;
    717 		}
    718 		if (isr & LE_C0_MERR) {
    719 			printf("%s: memory error\n", sc->sc_dev.dv_xname);
    720 			am7990_reset(sc);
    721 			return (1);
    722 		}
    723 	}
    724 
    725 	if ((isr & LE_C0_RXON) == 0) {
    726 		printf("%s: receiver disabled\n", sc->sc_dev.dv_xname);
    727 		ifp->if_ierrors++;
    728 		am7990_reset(sc);
    729 		return (1);
    730 	}
    731 	if ((isr & LE_C0_TXON) == 0) {
    732 		printf("%s: transmitter disabled\n", sc->sc_dev.dv_xname);
    733 		ifp->if_oerrors++;
    734 		am7990_reset(sc);
    735 		return (1);
    736 	}
    737 
    738 	if (isr & LE_C0_RINT)
    739 		am7990_rint(sc);
    740 	if (isr & LE_C0_TINT)
    741 		am7990_tint(sc);
    742 
    743 	return (1);
    744 }
    745 
    746 #undef	ifp
    747 
    748 void
    749 am7990_watchdog(ifp)
    750 	struct ifnet *ifp;
    751 {
    752 	struct am7990_softc *sc = ifp->if_softc;
    753 
    754 	log(LOG_ERR, "%s: device timeout\n", sc->sc_dev.dv_xname);
    755 	++ifp->if_oerrors;
    756 
    757 	am7990_reset(sc);
    758 }
    759 
    760 /*
    761  * Setup output on interface.
    762  * Get another datagram to send off of the interface queue, and map it to the
    763  * interface before starting the output.
    764  * Called only at splimp or interrupt level.
    765  */
    766 void
    767 am7990_start(ifp)
    768 	register struct ifnet *ifp;
    769 {
    770 	register struct am7990_softc *sc = ifp->if_softc;
    771 	register int bix;
    772 	register struct mbuf *m;
    773 	struct letmd tmd;
    774 	int rp;
    775 	int len;
    776 
    777 	if ((ifp->if_flags & (IFF_RUNNING | IFF_OACTIVE)) != IFF_RUNNING)
    778 		return;
    779 
    780 	bix = sc->sc_last_td;
    781 
    782 	for (;;) {
    783 		rp = LE_TMDADDR(sc, bix);
    784 		(*sc->sc_copyfromdesc)(sc, &tmd, rp, sizeof(tmd));
    785 
    786 		if (tmd.tmd1_bits & LE_T1_OWN) {
    787 			ifp->if_flags |= IFF_OACTIVE;
    788 			printf("missing buffer, no_td = %d, last_td = %d\n",
    789 			    sc->sc_no_td, sc->sc_last_td);
    790 		}
    791 
    792 		IF_DEQUEUE(&ifp->if_snd, m);
    793 		if (m == 0)
    794 			break;
    795 
    796 #if NBPFILTER > 0
    797 		/*
    798 		 * If BPF is listening on this interface, let it see the packet
    799 		 * before we commit it to the wire.
    800 		 */
    801 		if (ifp->if_bpf)
    802 			bpf_mtap(ifp->if_bpf, m);
    803 #endif
    804 
    805 		/*
    806 		 * Copy the mbuf chain into the transmit buffer.
    807 		 */
    808 		len = am7990_put(sc, LE_TBUFADDR(sc, bix), m);
    809 
    810 #ifdef LEDEBUG
    811 		if (len > ETHERMTU + sizeof(struct ether_header))
    812 			printf("packet length %d\n", len);
    813 #endif
    814 
    815 		ifp->if_timer = 5;
    816 
    817 		/*
    818 		 * Init transmit registers, and set transmit start flag.
    819 		 */
    820 		tmd.tmd1_bits = LE_T1_OWN | LE_T1_STP | LE_T1_ENP;
    821 		tmd.tmd2 = -len | LE_XMD2_ONES;
    822 		tmd.tmd3 = 0;
    823 
    824 		(*sc->sc_copytodesc)(sc, &tmd, rp, sizeof(tmd));
    825 
    826 #ifdef LEDEBUG
    827 		if (sc->sc_debug)
    828 			am7990_xmit_print(sc, sc->sc_last_td);
    829 #endif
    830 
    831 		(*sc->sc_wrcsr)(sc, LE_CSR0, LE_C0_INEA | LE_C0_TDMD);
    832 
    833 		if (++bix == sc->sc_ntbuf)
    834 			bix = 0;
    835 
    836 		if (++sc->sc_no_td == sc->sc_ntbuf) {
    837 			ifp->if_flags |= IFF_OACTIVE;
    838 			break;
    839 		}
    840 
    841 	}
    842 
    843 	sc->sc_last_td = bix;
    844 }
    845 
    846 /*
    847  * Process an ioctl request.
    848  */
    849 int
    850 am7990_ioctl(ifp, cmd, data)
    851 	register struct ifnet *ifp;
    852 	u_long cmd;
    853 	caddr_t data;
    854 {
    855 	register struct am7990_softc *sc = ifp->if_softc;
    856 	struct ifaddr *ifa = (struct ifaddr *)data;
    857 	struct ifreq *ifr = (struct ifreq *)data;
    858 	int s, error = 0;
    859 
    860 	s = splimp();
    861 
    862 	switch (cmd) {
    863 
    864 	case SIOCSIFADDR:
    865 		ifp->if_flags |= IFF_UP;
    866 
    867 		switch (ifa->ifa_addr->sa_family) {
    868 #ifdef INET
    869 		case AF_INET:
    870 			am7990_init(sc);
    871 			arp_ifinit(ifp, ifa);
    872 			break;
    873 #endif
    874 #ifdef NS
    875 		case AF_NS:
    876 		    {
    877 			register struct ns_addr *ina = &IA_SNS(ifa)->sns_addr;
    878 
    879 			if (ns_nullhost(*ina))
    880 				ina->x_host =
    881 				    *(union ns_host *)LLADDR(ifp->if_sadl);
    882 			else {
    883 				bcopy(ina->x_host.c_host,
    884 				    LLADDR(ifp->if_sadl),
    885 				    sizeof(sc->sc_enaddr));
    886 			}
    887 			/* Set new address. */
    888 			am7990_init(sc);
    889 			break;
    890 		    }
    891 #endif
    892 		default:
    893 			am7990_init(sc);
    894 			break;
    895 		}
    896 		break;
    897 
    898 #if defined(CCITT) && defined(LLC)
    899 	case SIOCSIFCONF_X25:
    900 		ifp->if_flags |= IFF_UP;
    901 		ifa->ifa_rtrequest = cons_rtrequest; /* XXX */
    902 		error = x25_llcglue(PRC_IFUP, ifa->ifa_addr);
    903 		if (error == 0)
    904 			am7990_init(sc);
    905 		break;
    906 #endif /* CCITT && LLC */
    907 
    908 	case SIOCSIFFLAGS:
    909 		if ((ifp->if_flags & IFF_UP) == 0 &&
    910 		    (ifp->if_flags & IFF_RUNNING) != 0) {
    911 			/*
    912 			 * If interface is marked down and it is running, then
    913 			 * stop it.
    914 			 */
    915 			am7990_stop(sc);
    916 			ifp->if_flags &= ~IFF_RUNNING;
    917 		} else if ((ifp->if_flags & IFF_UP) != 0 &&
    918 		    	   (ifp->if_flags & IFF_RUNNING) == 0) {
    919 			/*
    920 			 * If interface is marked up and it is stopped, then
    921 			 * start it.
    922 			 */
    923 			am7990_init(sc);
    924 		} else {
    925 			/*
    926 			 * Reset the interface to pick up changes in any other
    927 			 * flags that affect hardware registers.
    928 			 */
    929 			/*am7990_stop(sc);*/
    930 			am7990_init(sc);
    931 		}
    932 #ifdef LEDEBUG
    933 		if (ifp->if_flags & IFF_DEBUG)
    934 			sc->sc_debug = 1;
    935 		else
    936 			sc->sc_debug = 0;
    937 #endif
    938 		break;
    939 
    940 	case SIOCADDMULTI:
    941 	case SIOCDELMULTI:
    942 		error = (cmd == SIOCADDMULTI) ?
    943 		    ether_addmulti(ifr, &sc->sc_ethercom) :
    944 		    ether_delmulti(ifr, &sc->sc_ethercom);
    945 
    946 		if (error == ENETRESET) {
    947 			/*
    948 			 * Multicast list has changed; set the hardware filter
    949 			 * accordingly.
    950 			 */
    951 			am7990_reset(sc);
    952 			error = 0;
    953 		}
    954 		break;
    955 
    956 	default:
    957 		error = EINVAL;
    958 		break;
    959 	}
    960 
    961 	splx(s);
    962 	return (error);
    963 }
    964 
    965 hide void
    966 am7990_shutdown(arg)
    967 	void *arg;
    968 {
    969 
    970 	am7990_stop((struct am7990_softc *)arg);
    971 }
    972 
    973 #ifdef LEDEBUG
    974 void
    975 am7990_recv_print(sc, no)
    976 	struct am7990_softc *sc;
    977 	int no;
    978 {
    979 	struct lermd rmd;
    980 	u_int16_t len;
    981 	struct ether_header eh;
    982 
    983 	(*sc->sc_copyfromdesc)(sc, &rmd, LE_RMDADDR(sc, no), sizeof(rmd));
    984 	len = rmd.rmd3;
    985 	printf("%s: receive buffer %d, len = %d\n", sc->sc_dev.dv_xname, no,
    986 	    len);
    987 	printf("%s: status %04x\n", sc->sc_dev.dv_xname,
    988 	    (*sc->sc_rdcsr)(sc, LE_CSR0));
    989 	printf("%s: ladr %04x, hadr %02x, flags %02x, bcnt %04x, mcnt %04x\n",
    990 	    sc->sc_dev.dv_xname,
    991 	    rmd.rmd0, rmd.rmd1_hadr, rmd.rmd1_bits, rmd.rmd2, rmd.rmd3);
    992 	if (len >= sizeof(eh)) {
    993 		(*sc->sc_copyfrombuf)(sc, &eh, LE_RBUFADDR(sc, no), sizeof(eh));
    994 		printf("%s: dst %s", sc->sc_dev.dv_xname,
    995 			ether_sprintf(eh.ether_dhost));
    996 		printf(" src %s type %04x\n", ether_sprintf(eh.ether_shost),
    997 			ntohs(eh.ether_type));
    998 	}
    999 }
   1000 
   1001 void
   1002 am7990_xmit_print(sc, no)
   1003 	struct am7990_softc *sc;
   1004 	int no;
   1005 {
   1006 	struct letmd tmd;
   1007 	u_int16_t len;
   1008 	struct ether_header eh;
   1009 
   1010 	(*sc->sc_copyfromdesc)(sc, &tmd, LE_TMDADDR(sc, no), sizeof(tmd));
   1011 	len = -tmd.tmd2;
   1012 	printf("%s: transmit buffer %d, len = %d\n", sc->sc_dev.dv_xname, no,
   1013 	    len);
   1014 	printf("%s: status %04x\n", sc->sc_dev.dv_xname,
   1015 	    (*sc->sc_rdcsr)(sc, LE_CSR0));
   1016 	printf("%s: ladr %04x, hadr %02x, flags %02x, bcnt %04x, mcnt %04x\n",
   1017 	    sc->sc_dev.dv_xname,
   1018 	    tmd.tmd0, tmd.tmd1_hadr, tmd.tmd1_bits, tmd.tmd2, tmd.tmd3);
   1019 	if (len >= sizeof(eh)) {
   1020 		(*sc->sc_copyfrombuf)(sc, &eh, LE_TBUFADDR(sc, no), sizeof(eh));
   1021 		printf("%s: dst %s", sc->sc_dev.dv_xname,
   1022 			ether_sprintf(eh.ether_dhost));
   1023 		printf(" src %s type %04x\n", ether_sprintf(eh.ether_shost),
   1024 		    ntohs(eh.ether_type));
   1025 	}
   1026 }
   1027 #endif /* LEDEBUG */
   1028 
   1029 /*
   1030  * Set up the logical address filter.
   1031  */
   1032 void
   1033 am7990_setladrf(ac, af)
   1034 	struct ethercom *ac;
   1035 	u_int16_t *af;
   1036 {
   1037 	struct ifnet *ifp = &ac->ec_if;
   1038 	struct ether_multi *enm;
   1039 	register u_char *cp, c;
   1040 	register u_int32_t crc;
   1041 	register int i, len;
   1042 	struct ether_multistep step;
   1043 
   1044 	/*
   1045 	 * Set up multicast address filter by passing all multicast addresses
   1046 	 * through a crc generator, and then using the high order 6 bits as an
   1047 	 * index into the 64 bit logical address filter.  The high order bit
   1048 	 * selects the word, while the rest of the bits select the bit within
   1049 	 * the word.
   1050 	 */
   1051 
   1052 	if (ifp->if_flags & IFF_PROMISC)
   1053 		goto allmulti;
   1054 
   1055 	af[0] = af[1] = af[2] = af[3] = 0x0000;
   1056 	ETHER_FIRST_MULTI(step, ac, enm);
   1057 	while (enm != NULL) {
   1058 		if (ETHER_CMP(enm->enm_addrlo, enm->enm_addrhi)) {
   1059 			/*
   1060 			 * We must listen to a range of multicast addresses.
   1061 			 * For now, just accept all multicasts, rather than
   1062 			 * trying to set only those filter bits needed to match
   1063 			 * the range.  (At this time, the only use of address
   1064 			 * ranges is for IP multicast routing, for which the
   1065 			 * range is big enough to require all bits set.)
   1066 			 */
   1067 			goto allmulti;
   1068 		}
   1069 
   1070 		cp = enm->enm_addrlo;
   1071 		crc = 0xffffffff;
   1072 		for (len = sizeof(enm->enm_addrlo); --len >= 0;) {
   1073 			c = *cp++;
   1074 			for (i = 8; --i >= 0;) {
   1075 				if ((crc & 0x01) ^ (c & 0x01)) {
   1076 					crc >>= 1;
   1077 					crc ^= 0xedb88320;
   1078 				} else
   1079 					crc >>= 1;
   1080 				c >>= 1;
   1081 			}
   1082 		}
   1083 		/* Just want the 6 most significant bits. */
   1084 		crc >>= 26;
   1085 
   1086 		/* Set the corresponding bit in the filter. */
   1087 		af[crc >> 4] |= 1 << (crc & 0xf);
   1088 
   1089 		ETHER_NEXT_MULTI(step, enm);
   1090 	}
   1091 	ifp->if_flags &= ~IFF_ALLMULTI;
   1092 	return;
   1093 
   1094 allmulti:
   1095 	ifp->if_flags |= IFF_ALLMULTI;
   1096 	af[0] = af[1] = af[2] = af[3] = 0xffff;
   1097 }
   1098 
   1099 
   1100 /*
   1101  * Routines for accessing the transmit and receive buffers.
   1102  * The various CPU and adapter configurations supported by this
   1103  * driver require three different access methods for buffers
   1104  * and descriptors:
   1105  *	(1) contig (contiguous data; no padding),
   1106  *	(2) gap2 (two bytes of data followed by two bytes of padding),
   1107  *	(3) gap16 (16 bytes of data followed by 16 bytes of padding).
   1108  */
   1109 
   1110 /*
   1111  * contig: contiguous data with no padding.
   1112  *
   1113  * Buffers may have any alignment.
   1114  */
   1115 
   1116 void
   1117 am7990_copytobuf_contig(sc, from, boff, len)
   1118 	struct am7990_softc *sc;
   1119 	void *from;
   1120 	int boff, len;
   1121 {
   1122 	volatile caddr_t buf = sc->sc_mem;
   1123 
   1124 	/*
   1125 	 * Just call bcopy() to do the work.
   1126 	 */
   1127 	bcopy(from, buf + boff, len);
   1128 }
   1129 
   1130 void
   1131 am7990_copyfrombuf_contig(sc, to, boff, len)
   1132 	struct am7990_softc *sc;
   1133 	void *to;
   1134 	int boff, len;
   1135 {
   1136 	volatile caddr_t buf = sc->sc_mem;
   1137 
   1138 	/*
   1139 	 * Just call bcopy() to do the work.
   1140 	 */
   1141 	bcopy(buf + boff, to, len);
   1142 }
   1143 
   1144 void
   1145 am7990_zerobuf_contig(sc, boff, len)
   1146 	struct am7990_softc *sc;
   1147 	int boff, len;
   1148 {
   1149 	volatile caddr_t buf = sc->sc_mem;
   1150 
   1151 	/*
   1152 	 * Just let bzero() do the work
   1153 	 */
   1154 	bzero(buf + boff, len);
   1155 }
   1156 
   1157 #if 0
   1158 /*
   1159  * Examples only; duplicate these and tweak (if necessary) in
   1160  * machine-specific front-ends.
   1161  */
   1162 
   1163 /*
   1164  * gap2: two bytes of data followed by two bytes of pad.
   1165  *
   1166  * Buffers must be 4-byte aligned.  The code doesn't worry about
   1167  * doing an extra byte.
   1168  */
   1169 
   1170 void
   1171 am7990_copytobuf_gap2(sc, fromv, boff, len)
   1172 	struct am7990_softc *sc;
   1173 	void *fromv;
   1174 	int boff;
   1175 	register int len;
   1176 {
   1177 	volatile caddr_t buf = sc->sc_mem;
   1178 	register caddr_t from = fromv;
   1179 	register volatile u_int16_t *bptr;
   1180 
   1181 	if (boff & 0x1) {
   1182 		/* handle unaligned first byte */
   1183 		bptr = ((volatile u_int16_t *)buf) + (boff - 1);
   1184 		*bptr = (*from++ << 8) | (*bptr & 0xff);
   1185 		bptr += 2;
   1186 		len--;
   1187 	} else
   1188 		bptr = ((volatile u_int16_t *)buf) + boff;
   1189 	while (len > 1) {
   1190 		*bptr = (from[1] << 8) | (from[0] & 0xff);
   1191 		bptr += 2;
   1192 		from += 2;
   1193 		len -= 2;
   1194 	}
   1195 	if (len == 1)
   1196 		*bptr = (u_int16_t)*from;
   1197 }
   1198 
   1199 void
   1200 am7990_copyfrombuf_gap2(sc, tov, boff, len)
   1201 	struct am7990_softc *sc;
   1202 	void *tov;
   1203 	int boff, len;
   1204 {
   1205 	volatile caddr_t buf = sc->sc_mem;
   1206 	register caddr_t to = tov;
   1207 	register volatile u_int16_t *bptr;
   1208 	register u_int16_t tmp;
   1209 
   1210 	if (boff & 0x1) {
   1211 		/* handle unaligned first byte */
   1212 		bptr = ((volatile u_int16_t *)buf) + (boff - 1);
   1213 		*to++ = (*bptr >> 8) & 0xff;
   1214 		bptr += 2;
   1215 		len--;
   1216 	} else
   1217 		bptr = ((volatile u_int16_t *)buf) + boff;
   1218 	while (len > 1) {
   1219 		tmp = *bptr;
   1220 		*to++ = tmp & 0xff;
   1221 		*to++ = (tmp >> 8) & 0xff;
   1222 		bptr += 2;
   1223 		len -= 2;
   1224 	}
   1225 	if (len == 1)
   1226 		*to = *bptr & 0xff;
   1227 }
   1228 
   1229 void
   1230 am7990_zerobuf_gap2(sc, boff, len)
   1231 	struct am7990_softc *sc;
   1232 	int boff, len;
   1233 {
   1234 	volatile caddr_t buf = sc->sc_mem;
   1235 	register volatile u_int16_t *bptr;
   1236 
   1237 	if ((unsigned)boff & 0x1) {
   1238 		bptr = ((volatile u_int16_t *)buf) + (boff - 1);
   1239 		*bptr &= 0xff;
   1240 		bptr += 2;
   1241 		len--;
   1242 	} else
   1243 		bptr = ((volatile u_int16_t *)buf) + boff;
   1244 	while (len > 0) {
   1245 		*bptr = 0;
   1246 		bptr += 2;
   1247 		len -= 2;
   1248 	}
   1249 }
   1250 
   1251 /*
   1252  * gap16: 16 bytes of data followed by 16 bytes of pad.
   1253  *
   1254  * Buffers must be 32-byte aligned.
   1255  */
   1256 
   1257 void
   1258 am7990_copytobuf_gap16(sc, fromv, boff, len)
   1259 	struct am7990_softc *sc;
   1260 	void *fromv;
   1261 	int boff;
   1262 	register int len;
   1263 {
   1264 	volatile caddr_t buf = sc->sc_mem;
   1265 	register caddr_t from = fromv;
   1266 	register caddr_t bptr;
   1267 	register int xfer;
   1268 
   1269 	bptr = buf + ((boff << 1) & ~0x1f);
   1270 	boff &= 0xf;
   1271 	xfer = min(len, 16 - boff);
   1272 	while (len > 0) {
   1273 		bcopy(from, bptr + boff, xfer);
   1274 		from += xfer;
   1275 		bptr += 32;
   1276 		boff = 0;
   1277 		len -= xfer;
   1278 		xfer = min(len, 16);
   1279 	}
   1280 }
   1281 
   1282 void
   1283 am7990_copyfrombuf_gap16(sc, tov, boff, len)
   1284 	struct am7990_softc *sc;
   1285 	void *tov;
   1286 	int boff, len;
   1287 {
   1288 	volatile caddr_t buf = sc->sc_mem;
   1289 	register caddr_t to = tov;
   1290 	register caddr_t bptr;
   1291 	register int xfer;
   1292 
   1293 	bptr = buf + ((boff << 1) & ~0x1f);
   1294 	boff &= 0xf;
   1295 	xfer = min(len, 16 - boff);
   1296 	while (len > 0) {
   1297 		bcopy(bptr + boff, to, xfer);
   1298 		to += xfer;
   1299 		bptr += 32;
   1300 		boff = 0;
   1301 		len -= xfer;
   1302 		xfer = min(len, 16);
   1303 	}
   1304 }
   1305 
   1306 void
   1307 am7990_zerobuf_gap16(sc, boff, len)
   1308 	struct am7990_softc *sc;
   1309 	int boff, len;
   1310 {
   1311 	volatile caddr_t buf = sc->sc_mem;
   1312 	register caddr_t bptr;
   1313 	register int xfer;
   1314 
   1315 	bptr = buf + ((boff << 1) & ~0x1f);
   1316 	boff &= 0xf;
   1317 	xfer = min(len, 16 - boff);
   1318 	while (len > 0) {
   1319 		bzero(bptr + boff, xfer);
   1320 		bptr += 32;
   1321 		boff = 0;
   1322 		len -= xfer;
   1323 		xfer = min(len, 16);
   1324 	}
   1325 }
   1326 #endif /* Example only */
   1327