xref: /netbsd-src/sys/dev/ic/dm9000.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: dm9000.c,v 1.15 2018/06/26 06:48:00 msaitoh Exp $	*/
2 
3 /*
4  * Copyright (c) 2009 Paul Fleischer
5  * All rights reserved.
6  *
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  * 3. The name of the company nor the name of the author may be used to
13  *    endorse or promote products derived from this software without specific
14  *    prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
17  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
20  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 /* based on sys/dev/ic/cs89x0.c */
30 /*
31  * Copyright (c) 2004 Christopher Gilbert
32  * All rights reserved.
33  *
34  * 1. Redistributions of source code must retain the above copyright
35  *    notice, this list of conditions and the following disclaimer.
36  * 2. Redistributions in binary form must reproduce the above copyright
37  *    notice, this list of conditions and the following disclaimer in the
38  *    documentation and/or other materials provided with the distribution.
39  * 3. The name of the company nor the name of the author may be used to
40  *    endorse or promote products derived from this software without specific
41  *    prior written permission.
42  *
43  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
44  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
45  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
46  * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
47  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
48  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
49  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
50  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
51  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
52  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53  * SUCH DAMAGE.
54  */
55 
56 /*
57  * Copyright 1997
58  * Digital Equipment Corporation. All rights reserved.
59  *
60  * This software is furnished under license and may be used and
61  * copied only in accordance with the following terms and conditions.
62  * Subject to these conditions, you may download, copy, install,
63  * use, modify and distribute this software in source and/or binary
64  * form. No title or ownership is transferred hereby.
65  *
66  * 1) Any source code used, modified or distributed must reproduce
67  *    and retain this copyright notice and list of conditions as
68  *    they appear in the source file.
69  *
70  * 2) No right is granted to use any trade name, trademark, or logo of
71  *    Digital Equipment Corporation. Neither the "Digital Equipment
72  *    Corporation" name nor any trademark or logo of Digital Equipment
73  *    Corporation may be used to endorse or promote products derived
74  *    from this software without the prior written permission of
75  *    Digital Equipment Corporation.
76  *
77  * 3) This software is provided "AS-IS" and any express or implied
78  *    warranties, including but not limited to, any implied warranties
79  *    of merchantability, fitness for a particular purpose, or
80  *    non-infringement are disclaimed. In no event shall DIGITAL be
81  *    liable for any damages whatsoever, and in particular, DIGITAL
82  *    shall not be liable for special, indirect, consequential, or
83  *    incidental damages or damages for lost profits, loss of
84  *    revenue or loss of use, whether such damages arise in contract,
85  *    negligence, tort, under statute, in equity, at law or otherwise,
86  *    even if advised of the possibility of such damage.
87  */
88 
89 #include <sys/cdefs.h>
90 
91 #include <sys/param.h>
92 #include <sys/kernel.h>
93 #include <sys/systm.h>
94 #include <sys/mbuf.h>
95 #include <sys/syslog.h>
96 #include <sys/socket.h>
97 #include <sys/device.h>
98 #include <sys/malloc.h>
99 #include <sys/ioctl.h>
100 #include <sys/errno.h>
101 
102 #include <net/if.h>
103 #include <net/if_ether.h>
104 #include <net/if_media.h>
105 #include <net/bpf.h>
106 
107 #ifdef INET
108 #include <netinet/in.h>
109 #include <netinet/if_inarp.h>
110 #endif
111 
112 #include <sys/bus.h>
113 #include <sys/intr.h>
114 
115 #include <dev/ic/dm9000var.h>
116 #include <dev/ic/dm9000reg.h>
117 
118 #if 1
119 #undef DM9000_DEBUG
120 #undef DM9000_TX_DEBUG
121 #undef DM9000_TX_DATA_DEBUG
122 #undef DM9000_RX_DEBUG
123 #undef  DM9000_RX_DATA_DEBUG
124 #else
125 #define DM9000_DEBUG
126 #define  DM9000_TX_DEBUG
127 #define DM9000_TX_DATA_DEBUG
128 #define DM9000_RX_DEBUG
129 #define  DM9000_RX_DATA_DEBUG
130 #endif
131 
132 #ifdef DM9000_DEBUG
133 #define DPRINTF(s) do {printf s; } while (/*CONSTCOND*/0)
134 #else
135 #define DPRINTF(s) do {} while (/*CONSTCOND*/0)
136 #endif
137 
138 #ifdef DM9000_TX_DEBUG
139 #define TX_DPRINTF(s) do {printf s; } while (/*CONSTCOND*/0)
140 #else
141 #define TX_DPRINTF(s) do {} while (/*CONSTCOND*/0)
142 #endif
143 
144 #ifdef DM9000_RX_DEBUG
145 #define RX_DPRINTF(s) do {printf s; } while (/*CONSTCOND*/0)
146 #else
147 #define RX_DPRINTF(s) do {} while (/*CONSTCOND*/0)
148 #endif
149 
150 #ifdef DM9000_RX_DATA_DEBUG
151 #define RX_DATA_DPRINTF(s) do {printf s; } while (/*CONSTCOND*/0)
152 #else
153 #define RX_DATA_DPRINTF(s) do {} while (/*CONSTCOND*/0)
154 #endif
155 
156 #ifdef DM9000_TX_DATA_DEBUG
157 #define TX_DATA_DPRINTF(s) do {printf s; } while (/*CONSTCOND*/0)
158 #else
159 #define TX_DATA_DPRINTF(s) do {} while (/*CONSTCOND*/0)
160 #endif
161 
162 /*** Internal PHY functions ***/
163 uint16_t dme_phy_read(struct dme_softc *, int );
164 void	dme_phy_write(struct dme_softc *, int, uint16_t);
165 void	dme_phy_init(struct dme_softc *);
166 void	dme_phy_reset(struct dme_softc *);
167 void	dme_phy_update_media(struct dme_softc *);
168 void	dme_phy_check_link(void *);
169 
170 /*** Methods registered in struct ifnet ***/
171 void	dme_start_output(struct ifnet *);
172 int	dme_init(struct ifnet *);
173 int	dme_ioctl(struct ifnet *, u_long, void *);
174 void	dme_stop(struct ifnet *, int);
175 
176 int	dme_mediachange(struct ifnet *);
177 void	dme_mediastatus(struct ifnet *, struct ifmediareq *);
178 
179 /*** Internal methods ***/
180 
181 /* Prepare data to be transmitted (i.e. dequeue and load it into the DM9000) */
182 void    dme_prepare(struct dme_softc *, struct ifnet *);
183 
184 /* Transmit prepared data */
185 void    dme_transmit(struct dme_softc *);
186 
187 /* Receive data */
188 void    dme_receive(struct dme_softc *, struct ifnet *);
189 
190 /* Software Initialize/Reset of the DM9000 */
191 void    dme_reset(struct dme_softc *);
192 
193 /* Configure multicast filter */
194 void	dme_set_addr_filter(struct dme_softc *);
195 
196 /* Set media */
197 int	dme_set_media(struct dme_softc *, int );
198 
199 /* Read/write packet data from/to DM9000 IC in various transfer sizes */
200 int	dme_pkt_read_2(struct dme_softc *, struct ifnet *, struct mbuf **);
201 int	dme_pkt_write_2(struct dme_softc *, struct mbuf *);
202 int	dme_pkt_read_1(struct dme_softc *, struct ifnet *, struct mbuf **);
203 int	dme_pkt_write_1(struct dme_softc *, struct mbuf *);
204 /* TODO: Implement 32 bit read/write functions */
205 
206 uint16_t
207 dme_phy_read(struct dme_softc *sc, int reg)
208 {
209 	uint16_t val;
210 	/* Select Register to read*/
211 	dme_write(sc, DM9000_EPAR, DM9000_EPAR_INT_PHY +
212 	    (reg & DM9000_EPAR_EROA_MASK));
213 	/* Select read operation (DM9000_EPCR_ERPRR) from the PHY */
214 	dme_write(sc, DM9000_EPCR, DM9000_EPCR_ERPRR + DM9000_EPCR_EPOS_PHY);
215 
216 	/* Wait until access to PHY has completed */
217 	while (dme_read(sc, DM9000_EPCR) & DM9000_EPCR_ERRE);
218 
219 	/* Reset ERPRR-bit */
220 	dme_write(sc, DM9000_EPCR, DM9000_EPCR_EPOS_PHY);
221 
222 	val = dme_read(sc, DM9000_EPDRL);
223 	val += dme_read(sc, DM9000_EPDRH) << 8;
224 
225 	return val;
226 }
227 
228 void
229 dme_phy_write(struct dme_softc *sc, int reg, uint16_t value)
230 {
231 	/* Select Register to write*/
232 	dme_write(sc, DM9000_EPAR, DM9000_EPAR_INT_PHY +
233 	    (reg & DM9000_EPAR_EROA_MASK));
234 
235 	/* Write data to the two data registers */
236 	dme_write(sc, DM9000_EPDRL, value & 0xFF);
237 	dme_write(sc, DM9000_EPDRH, (value >> 8) & 0xFF);
238 
239 	/* Select write operation (DM9000_EPCR_ERPRW) from the PHY */
240 	dme_write(sc, DM9000_EPCR, DM9000_EPCR_ERPRW + DM9000_EPCR_EPOS_PHY);
241 
242 	/* Wait until access to PHY has completed */
243 	while(dme_read(sc, DM9000_EPCR) & DM9000_EPCR_ERRE);
244 
245 	/* Reset ERPRR-bit */
246 	dme_write(sc, DM9000_EPCR, DM9000_EPCR_EPOS_PHY);
247 }
248 
249 void
250 dme_phy_init(struct dme_softc *sc)
251 {
252 	u_int ifm_media = sc->sc_media.ifm_media;
253 	uint32_t bmcr, anar;
254 
255 	bmcr = dme_phy_read(sc, DM9000_PHY_BMCR);
256 	anar = dme_phy_read(sc, DM9000_PHY_ANAR);
257 
258 	anar = anar & ~DM9000_PHY_ANAR_10_HDX
259 		& ~DM9000_PHY_ANAR_10_FDX
260 		& ~DM9000_PHY_ANAR_TX_HDX
261 		& ~DM9000_PHY_ANAR_TX_FDX;
262 
263 	switch (IFM_SUBTYPE(ifm_media)) {
264 	case IFM_AUTO:
265 		bmcr |= DM9000_PHY_BMCR_AUTO_NEG_EN;
266 		anar |= DM9000_PHY_ANAR_10_HDX |
267 			DM9000_PHY_ANAR_10_FDX |
268 			DM9000_PHY_ANAR_TX_HDX |
269 			DM9000_PHY_ANAR_TX_FDX;
270 		break;
271 	case IFM_10_T:
272 		//bmcr &= ~DM9000_PHY_BMCR_AUTO_NEG_EN;
273 		bmcr &= ~DM9000_PHY_BMCR_SPEED_SELECT;
274 		if (ifm_media & IFM_FDX)
275 			anar |= DM9000_PHY_ANAR_10_FDX;
276 		else
277 			anar |= DM9000_PHY_ANAR_10_HDX;
278 		break;
279 	case IFM_100_TX:
280 		//bmcr &= ~DM9000_PHY_BMCR_AUTO_NEG_EN;
281 		bmcr |= DM9000_PHY_BMCR_SPEED_SELECT;
282 		if (ifm_media & IFM_FDX)
283 			anar |= DM9000_PHY_ANAR_TX_FDX;
284 		else
285 			anar |= DM9000_PHY_ANAR_TX_HDX;
286 
287 		break;
288 	}
289 
290 	if(ifm_media & IFM_FDX) {
291 		bmcr |= DM9000_PHY_BMCR_DUPLEX_MODE;
292 	} else {
293 		bmcr &= ~DM9000_PHY_BMCR_DUPLEX_MODE;
294 	}
295 
296 	dme_phy_write(sc, DM9000_PHY_BMCR, bmcr);
297 	dme_phy_write(sc, DM9000_PHY_ANAR, anar);
298 }
299 
300 void
301 dme_phy_reset(struct dme_softc *sc)
302 {
303 	uint32_t reg;
304 
305 	/* PHY Reset */
306 	dme_phy_write(sc, DM9000_PHY_BMCR, DM9000_PHY_BMCR_RESET);
307 
308 	reg = dme_read(sc, DM9000_GPCR);
309 	dme_write(sc, DM9000_GPCR, reg & ~DM9000_GPCR_GPIO0_OUT);
310 	reg = dme_read(sc, DM9000_GPR);
311 	dme_write(sc, DM9000_GPR, reg | DM9000_GPR_PHY_PWROFF);
312 
313 	dme_phy_init(sc);
314 
315 	reg = dme_read(sc, DM9000_GPR);
316 	dme_write(sc, DM9000_GPR, reg & ~DM9000_GPR_PHY_PWROFF);
317 	reg = dme_read(sc, DM9000_GPCR);
318 	dme_write(sc, DM9000_GPCR, reg | DM9000_GPCR_GPIO0_OUT);
319 
320 	dme_phy_update_media(sc);
321 }
322 
323 void
324 dme_phy_update_media(struct dme_softc *sc)
325 {
326 	u_int ifm_media = sc->sc_media.ifm_media;
327 	uint32_t reg;
328 
329 	if (IFM_SUBTYPE(ifm_media) == IFM_AUTO) {
330 		/* If auto-negotiation is used, ensures that it is completed
331 		 before trying to extract any media information. */
332 		reg = dme_phy_read(sc, DM9000_PHY_BMSR);
333 		if ((reg & DM9000_PHY_BMSR_AUTO_NEG_AB) == 0) {
334 			/* Auto-negotation not possible, therefore there is no
335 			   reason to try obtain any media information. */
336 			return;
337 		}
338 
339 		/* Then loop until the negotiation is completed. */
340 		while ((reg & DM9000_PHY_BMSR_AUTO_NEG_COM) == 0) {
341 			/* TODO: Bail out after a finite number of attempts
342 			 in case something goes wrong. */
343 			preempt();
344 			reg = dme_phy_read(sc, DM9000_PHY_BMSR);
345 		}
346 	}
347 
348 
349 	sc->sc_media_active = IFM_ETHER;
350 	reg = dme_phy_read(sc, DM9000_PHY_BMCR);
351 
352 	if (reg & DM9000_PHY_BMCR_SPEED_SELECT) {
353 		sc->sc_media_active |= IFM_100_TX;
354 	} else {
355 		sc->sc_media_active |= IFM_10_T;
356 	}
357 
358 	if (reg & DM9000_PHY_BMCR_DUPLEX_MODE) {
359 		sc->sc_media_active |= IFM_FDX;
360 	}
361 }
362 
363 void
364 dme_phy_check_link(void *arg)
365 {
366 	struct dme_softc *sc = arg;
367 	uint32_t reg;
368 	int s;
369 
370 	s = splnet();
371 
372 	reg = dme_read(sc, DM9000_NSR) & DM9000_NSR_LINKST;
373 
374 	if( reg )
375 		reg = IFM_ETHER | IFM_AVALID | IFM_ACTIVE;
376 	else {
377 		reg = IFM_ETHER | IFM_AVALID;
378 		sc->sc_media_active = IFM_NONE;
379 	}
380 
381 	if ( (sc->sc_media_status != reg) && (reg & IFM_ACTIVE)) {
382 		dme_phy_reset(sc);
383 	}
384 
385 	sc->sc_media_status = reg;
386 
387 	callout_schedule(&sc->sc_link_callout, mstohz(2000));
388 	splx(s);
389 }
390 
391 int
392 dme_set_media(struct dme_softc *sc, int media)
393 {
394 	int s;
395 
396 	s = splnet();
397 	sc->sc_media.ifm_media = media;
398 	dme_phy_reset(sc);
399 
400 	splx(s);
401 
402 	return 0;
403 }
404 
405 int
406 dme_attach(struct dme_softc *sc, const uint8_t *enaddr)
407 {
408 	struct ifnet	*ifp = &sc->sc_ethercom.ec_if;
409 	uint8_t		b[2];
410 	uint16_t	io_mode;
411 
412 	dme_read_c(sc, DM9000_VID0, b, 2);
413 #if BYTE_ORDER == BIG_ENDIAN
414 	sc->sc_vendor_id = (b[0] << 8) | b[1];
415 #else
416 	sc->sc_vendor_id = b[0] | (b[1] << 8);
417 #endif
418 	dme_read_c(sc, DM9000_PID0, b, 2);
419 #if BYTE_ORDER == BIG_ENDIAN
420 	sc->sc_product_id = (b[0] << 8) | b[1];
421 #else
422 	sc->sc_product_id = b[0] | (b[1] << 8);
423 #endif
424 	/* TODO: Check the vendor ID as well */
425 	if (sc->sc_product_id != 0x9000) {
426 		panic("dme_attach: product id mismatch (0x%hx != 0x9000)",
427 		    sc->sc_product_id);
428 	}
429 
430 	/* Initialize ifnet structure. */
431 	strlcpy(ifp->if_xname, device_xname(sc->sc_dev), IFNAMSIZ);
432 	ifp->if_softc = sc;
433 	ifp->if_start = dme_start_output;
434 	ifp->if_init = dme_init;
435 	ifp->if_ioctl = dme_ioctl;
436 	ifp->if_stop = dme_stop;
437 	ifp->if_watchdog = NULL;	/* no watchdog at this stage */
438 	ifp->if_flags = IFF_SIMPLEX | IFF_NOTRAILERS | IFF_BROADCAST |
439 			IFF_MULTICAST;
440 	IFQ_SET_READY(&ifp->if_snd);
441 
442 	/* Initialize ifmedia structures. */
443 	ifmedia_init(&sc->sc_media, 0, dme_mediachange, dme_mediastatus);
444 	ifmedia_add(&sc->sc_media, IFM_ETHER|IFM_AUTO, 0, NULL);
445 	ifmedia_add(&sc->sc_media, IFM_ETHER|IFM_10_T|IFM_FDX, 0, NULL);
446 	ifmedia_add(&sc->sc_media, IFM_ETHER|IFM_10_T, 0, NULL);
447 	ifmedia_add(&sc->sc_media, IFM_ETHER|IFM_100_TX|IFM_FDX, 0, NULL);
448 	ifmedia_add(&sc->sc_media, IFM_ETHER|IFM_100_TX, 0, NULL);
449 
450 	ifmedia_set(&sc->sc_media, IFM_ETHER|IFM_AUTO);
451 
452 	if (enaddr != NULL)
453 		memcpy(sc->sc_enaddr, enaddr, sizeof(sc->sc_enaddr));
454 	/* TODO: Support an EEPROM attached to the DM9000 chip */
455 
456 	callout_init(&sc->sc_link_callout, 0);
457 	callout_setfunc(&sc->sc_link_callout, dme_phy_check_link, sc);
458 
459 	sc->sc_media_status = 0;
460 
461 	/* Configure DM9000 with the MAC address */
462 	dme_write_c(sc, DM9000_PAB0, sc->sc_enaddr, 6);
463 
464 #ifdef DM9000_DEBUG
465 	{
466 		uint8_t macAddr[6];
467 		dme_read_c(sc, DM9000_PAB0, macAddr, 6);
468 		printf("DM9000 configured with MAC address: ");
469 		for (int i = 0; i < 6; i++) {
470 			printf("%02X:", macAddr[i]);
471 		}
472 		printf("\n");
473 	}
474 #endif
475 
476 	if_attach(ifp);
477 	ether_ifattach(ifp, sc->sc_enaddr);
478 
479 #ifdef DM9000_DEBUG
480 	{
481 		uint8_t network_state;
482 		network_state = dme_read(sc, DM9000_NSR);
483 		printf("DM9000 Link status: ");
484 		if (network_state & DM9000_NSR_LINKST) {
485 			if (network_state & DM9000_NSR_SPEED)
486 				printf("10Mbps");
487 			else
488 				printf("100Mbps");
489 		} else {
490 			printf("Down");
491 		}
492 		printf("\n");
493 	}
494 #endif
495 
496 	io_mode = (dme_read(sc, DM9000_ISR) &
497 	    DM9000_IOMODE_MASK) >> DM9000_IOMODE_SHIFT;
498 
499 	DPRINTF(("DM9000 Operation Mode: "));
500 	switch( io_mode) {
501 	case DM9000_MODE_16BIT:
502 		DPRINTF(("16-bit mode"));
503 		sc->sc_data_width = 2;
504 		sc->sc_pkt_write = dme_pkt_write_2;
505 		sc->sc_pkt_read = dme_pkt_read_2;
506 		break;
507 	case DM9000_MODE_32BIT:
508 		DPRINTF(("32-bit mode"));
509 		sc->sc_data_width = 4;
510 		panic("32bit mode is unsupported\n");
511 		break;
512 	case DM9000_MODE_8BIT:
513 		DPRINTF(("8-bit mode"));
514 		sc->sc_data_width = 1;
515 		sc->sc_pkt_write = dme_pkt_write_1;
516 		sc->sc_pkt_read = dme_pkt_read_1;
517 		break;
518 	default:
519 		DPRINTF(("Invalid mode"));
520 		break;
521 	}
522 	DPRINTF(("\n"));
523 
524 	callout_schedule(&sc->sc_link_callout, mstohz(2000));
525 
526 	return 0;
527 }
528 
529 int dme_intr(void *arg)
530 {
531 	struct dme_softc *sc = arg;
532 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
533 	uint8_t status;
534 
535 
536 	DPRINTF(("dme_intr: Begin\n"));
537 
538 	/* Disable interrupts */
539 	dme_write(sc, DM9000_IMR, DM9000_IMR_PAR );
540 
541 	status = dme_read(sc, DM9000_ISR);
542 	dme_write(sc, DM9000_ISR, status);
543 
544 	if (status & DM9000_ISR_PRS) {
545 		if (ifp->if_flags & IFF_RUNNING )
546 			dme_receive(sc, ifp);
547 	}
548 	if (status & DM9000_ISR_PTS) {
549 		uint8_t nsr;
550 		uint8_t tx_status = 0x01; /* Initialize to an error value */
551 
552 		/* A packet has been transmitted */
553 		sc->txbusy = 0;
554 
555 		nsr = dme_read(sc, DM9000_NSR);
556 
557 		if (nsr & DM9000_NSR_TX1END) {
558 			tx_status = dme_read(sc, DM9000_TSR1);
559 			TX_DPRINTF(("dme_intr: Sent using channel 0\n"));
560 		} else if (nsr & DM9000_NSR_TX2END) {
561 			tx_status = dme_read(sc, DM9000_TSR2);
562 			TX_DPRINTF(("dme_intr: Sent using channel 1\n"));
563 		}
564 
565 		if (tx_status == 0x0) {
566 			/* Frame successfully sent */
567 			ifp->if_opackets++;
568 		} else {
569 			ifp->if_oerrors++;
570 		}
571 
572 		/* If we have nothing ready to transmit, prepare something */
573 		if (!sc->txready) {
574 			dme_prepare(sc, ifp);
575 		}
576 
577 		if (sc->txready)
578 			dme_transmit(sc);
579 
580 		/* Prepare the next frame */
581 		dme_prepare(sc, ifp);
582 
583 	}
584 #ifdef notyet
585 	if (status & DM9000_ISR_LNKCHNG) {
586 	}
587 #endif
588 
589 	/* Enable interrupts again */
590 	dme_write(sc, DM9000_IMR, DM9000_IMR_PAR | DM9000_IMR_PRM |
591 		 DM9000_IMR_PTM);
592 
593 	DPRINTF(("dme_intr: End\n"));
594 
595 	return 1;
596 }
597 
598 void
599 dme_start_output(struct ifnet *ifp)
600 {
601 	struct dme_softc *sc;
602 
603 	sc = ifp->if_softc;
604 
605 	DPRINTF(("dme_start_output: Begin\n"));
606 
607 	if ((ifp->if_flags & (IFF_RUNNING | IFF_OACTIVE)) != IFF_RUNNING) {
608 		printf("No output\n");
609 		return;
610 	}
611 
612 	if (sc->txbusy && sc->txready) {
613 		panic("DM9000: Internal error, trying to send without"
614 		    " any empty queue\n");
615 	}
616 
617 	dme_prepare(sc, ifp);
618 
619 	if (sc->txbusy == 0) {
620 		/* We are ready to transmit right away */
621 		dme_transmit(sc);
622 		dme_prepare(sc, ifp); /* Prepare next one */
623 	} else {
624 		/* We need to wait until the current packet has
625 		 * been transmitted.
626 		 */
627 		ifp->if_flags |= IFF_OACTIVE;
628 	}
629 
630 	DPRINTF(("dme_start_output: End\n"));
631 }
632 
633 void
634 dme_prepare(struct dme_softc *sc, struct ifnet *ifp)
635 {
636 	struct mbuf *bufChain;
637 	uint16_t length;
638 
639 	TX_DPRINTF(("dme_prepare: Entering\n"));
640 
641 	if (sc->txready)
642 		panic("dme_prepare: Someone called us with txready set\n");
643 
644 	IFQ_DEQUEUE(&ifp->if_snd, bufChain);
645 	if (bufChain == NULL) {
646 		TX_DPRINTF(("dme_prepare: Nothing to transmit\n"));
647 		ifp->if_flags &= ~IFF_OACTIVE; /* Clear OACTIVE bit */
648 		return; /* Nothing to transmit */
649 	}
650 
651 	/* Element has now been removed from the queue, so we better send it */
652 
653 	bpf_mtap(ifp, bufChain, BPF_D_OUT);
654 
655 	/* Setup the DM9000 to accept the writes, and then write each buf in
656 	   the chain. */
657 
658 	TX_DATA_DPRINTF(("dme_prepare: Writing data: "));
659 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, sc->dme_io, DM9000_MWCMD);
660 	length = sc->sc_pkt_write(sc, bufChain);
661 	TX_DATA_DPRINTF(("\n"));
662 
663 	if (length % sc->sc_data_width != 0) {
664 		panic("dme_prepare: length is not compatible with IO_MODE");
665 	}
666 
667 	sc->txready_length = length;
668 	sc->txready = 1;
669 
670 	TX_DPRINTF(("dme_prepare: txbusy: %d\ndme_prepare: "
671 		"txready: %d, txready_length: %d\n",
672 		sc->txbusy, sc->txready, sc->txready_length));
673 
674 	m_freem(bufChain);
675 
676 	TX_DPRINTF(("dme_prepare: Leaving\n"));
677 }
678 
679 int
680 dme_init(struct ifnet *ifp)
681 {
682 	int s;
683 	struct dme_softc *sc = ifp->if_softc;
684 
685 	dme_stop(ifp, 0);
686 
687 	s = splnet();
688 
689 	dme_reset(sc);
690 
691 	sc->sc_ethercom.ec_if.if_flags |= IFF_RUNNING;
692 	sc->sc_ethercom.ec_if.if_flags &= ~IFF_OACTIVE;
693 	sc->sc_ethercom.ec_if.if_timer = 0;
694 
695 	splx(s);
696 
697 	return 0;
698 }
699 
700 int
701 dme_ioctl(struct ifnet *ifp, u_long cmd, void *data)
702 {
703 	struct dme_softc *sc = ifp->if_softc;
704 	struct ifreq *ifr = data;
705 	int s, error = 0;
706 
707 	s = splnet();
708 
709 	switch(cmd) {
710 	case SIOCGIFMEDIA:
711 	case SIOCSIFMEDIA:
712 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_media, cmd);
713 		break;
714 	default:
715 		error = ether_ioctl(ifp, cmd, data);
716 		if (error == ENETRESET) {
717 			if (ifp->if_flags && IFF_RUNNING) {
718 				/* Address list has changed, reconfigure
719 				   filter */
720 				dme_set_addr_filter(sc);
721 			}
722 			error = 0;
723 		}
724 		break;
725 	}
726 
727 	splx(s);
728 	return error;
729 }
730 
731 void
732 dme_stop(struct ifnet *ifp, int disable)
733 {
734 	struct dme_softc *sc = ifp->if_softc;
735 
736 	/* Not quite sure what to do when called with disable == 0 */
737 	if (disable) {
738 		/* Disable RX */
739 		dme_write(sc, DM9000_RCR, 0x0);
740 	}
741 
742 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
743 	ifp->if_timer = 0;
744 }
745 
746 int
747 dme_mediachange(struct ifnet *ifp)
748 {
749 	struct dme_softc *sc = ifp->if_softc;
750 
751 	return dme_set_media(sc, sc->sc_media.ifm_cur->ifm_media);
752 }
753 
754 void
755 dme_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
756 {
757 	struct dme_softc *sc = ifp->if_softc;
758 
759 	ifmr->ifm_active = sc->sc_media_active;
760 	ifmr->ifm_status = sc->sc_media_status;
761 }
762 
763 void
764 dme_transmit(struct dme_softc *sc)
765 {
766 
767 	TX_DPRINTF(("dme_transmit: PRE: txready: %d, txbusy: %d\n",
768 		sc->txready, sc->txbusy));
769 
770 	dme_write(sc, DM9000_TXPLL, sc->txready_length & 0xff);
771 	dme_write(sc, DM9000_TXPLH, (sc->txready_length >> 8) & 0xff );
772 
773 	/* Request to send the packet */
774 	dme_read(sc, DM9000_ISR);
775 
776 	dme_write(sc, DM9000_TCR, DM9000_TCR_TXREQ);
777 
778 	sc->txready = 0;
779 	sc->txbusy = 1;
780 	sc->txready_length = 0;
781 }
782 
783 void
784 dme_receive(struct dme_softc *sc, struct ifnet *ifp)
785 {
786 	uint8_t ready = 0x01;
787 
788 	DPRINTF(("inside dme_receive\n"));
789 
790 	while (ready == 0x01) {
791 		/* Packet received, retrieve it */
792 
793 		/* Read without address increment to get the ready byte without
794 		   moving past it. */
795 		bus_space_write_1(sc->sc_iot, sc->sc_ioh,
796 		    sc->dme_io, DM9000_MRCMDX);
797 		/* Dummy ready */
798 		ready = bus_space_read_1(sc->sc_iot, sc->sc_ioh, sc->dme_data);
799 		ready = bus_space_read_1(sc->sc_iot, sc->sc_ioh, sc->dme_data);
800 		ready &= 0x03;	/* we only want bits 1:0 */
801 		if (ready == 0x01) {
802 			uint8_t		rx_status;
803 			struct mbuf	*m;
804 
805 			/* Read with address increment. */
806 			bus_space_write_1(sc->sc_iot, sc->sc_ioh,
807 					  sc->dme_io, DM9000_MRCMD);
808 
809 			rx_status = sc->sc_pkt_read(sc, ifp, &m);
810 			if (m == NULL) {
811 				/* failed to allocate a receive buffer */
812 				ifp->if_ierrors++;
813 				RX_DPRINTF(("dme_receive: "
814 					"Error allocating buffer\n"));
815 			} else if (rx_status & (DM9000_RSR_CE | DM9000_RSR_PLE)) {
816 				/* Error while receiving the packet,
817 				 * discard it and keep track of counters
818 				 */
819 				ifp->if_ierrors++;
820 				RX_DPRINTF(("dme_receive: "
821 					"Error reciving packet\n"));
822 			} else if (rx_status & DM9000_RSR_LCS) {
823 				ifp->if_collisions++;
824 			} else {
825 				if_percpuq_enqueue(ifp->if_percpuq, m);
826 			}
827 
828 		} else if (ready != 0x00) {
829 			/* Should this be logged somehow? */
830 			printf("%s: Resetting chip\n",
831 			       device_xname(sc->sc_dev));
832 			dme_reset(sc);
833 		}
834 	}
835 }
836 
837 void
838 dme_reset(struct dme_softc *sc)
839 {
840 	uint8_t var;
841 
842 	/* We only re-initialized the PHY in this function the first time it is
843 	   called. */
844 	if( !sc->sc_phy_initialized) {
845 		/* PHY Reset */
846 		dme_phy_write(sc, DM9000_PHY_BMCR, DM9000_PHY_BMCR_RESET);
847 
848 		/* PHY Power Down */
849 		var = dme_read(sc, DM9000_GPR);
850 		dme_write(sc, DM9000_GPR, var | DM9000_GPR_PHY_PWROFF);
851 	}
852 
853 	/* Reset the DM9000 twice, as described in section 2 of the Programming
854 	   Guide.
855 	   The PHY is initialized and enabled between those two resets.
856 	 */
857 
858 	/* Software Reset*/
859 	dme_write(sc, DM9000_NCR,
860 	    DM9000_NCR_RST | DM9000_NCR_LBK_MAC_INTERNAL);
861 	delay(20);
862 	dme_write(sc, DM9000_NCR, 0x0);
863 
864 	if( !sc->sc_phy_initialized) {
865 		/* PHY Initialization */
866 		dme_phy_init(sc);
867 
868 		/* PHY Enable */
869 		var = dme_read(sc, DM9000_GPR);
870 		dme_write(sc, DM9000_GPR, var & ~DM9000_GPR_PHY_PWROFF);
871 		var = dme_read(sc, DM9000_GPCR);
872 		dme_write(sc, DM9000_GPCR, var | DM9000_GPCR_GPIO0_OUT);
873 
874 		dme_write(sc, DM9000_NCR,
875 			  DM9000_NCR_RST | DM9000_NCR_LBK_MAC_INTERNAL);
876 		delay(20);
877 		dme_write(sc, DM9000_NCR, 0x0);
878 	}
879 
880 	/* Select internal PHY, no wakeup event, no collosion mode,
881 	 * normal loopback mode.
882 	 */
883 	dme_write(sc, DM9000_NCR, DM9000_NCR_LBK_NORMAL );
884 
885 	/* Will clear TX1END, TX2END, and WAKEST fields by reading DM9000_NSR*/
886 	dme_read(sc, DM9000_NSR);
887 
888 	/* Enable wraparound of read/write pointer, packet received latch,
889 	 * and packet transmitted latch.
890 	 */
891 	dme_write(sc, DM9000_IMR,
892 	    DM9000_IMR_PAR | DM9000_IMR_PRM | DM9000_IMR_PTM);
893 
894 	/* Setup multicast address filter, and enable RX. */
895 	dme_set_addr_filter(sc);
896 
897 	/* Obtain media information from PHY */
898 	dme_phy_update_media(sc);
899 
900 	sc->txbusy = 0;
901 	sc->txready = 0;
902 	sc->sc_phy_initialized = 1;
903 }
904 
905 void
906 dme_set_addr_filter(struct dme_softc *sc)
907 {
908 	struct ether_multi	*enm;
909 	struct ether_multistep	step;
910 	struct ethercom		*ec;
911 	struct ifnet		*ifp;
912 	uint16_t		af[4];
913 	int			i;
914 
915 	ec = &sc->sc_ethercom;
916 	ifp = &ec->ec_if;
917 
918 	if (ifp->if_flags & IFF_PROMISC) {
919 		dme_write(sc, DM9000_RCR, DM9000_RCR_RXEN  |
920 					  DM9000_RCR_WTDIS |
921 					  DM9000_RCR_PRMSC);
922 		ifp->if_flags |= IFF_ALLMULTI;
923 		return;
924 	}
925 
926 	af[0] = af[1] = af[2] = af[3] = 0x0000;
927 	ifp->if_flags &= ~IFF_ALLMULTI;
928 
929 	ETHER_FIRST_MULTI(step, ec, enm);
930 	while (enm != NULL) {
931 		uint16_t hash;
932 		if (memcpy(enm->enm_addrlo, enm->enm_addrhi,
933 		    sizeof(enm->enm_addrlo))) {
934 			/*
935 	                 * We must listen to a range of multicast addresses.
936 	                 * For now, just accept all multicasts, rather than
937 	                 * trying to set only those filter bits needed to match
938 	                 * the range.  (At this time, the only use of address
939 	                 * ranges is for IP multicast routing, for which the
940 	                 * range is big enough to require all bits set.)
941 	                 */
942 			ifp->if_flags |= IFF_ALLMULTI;
943 			af[0] = af[1] = af[2] = af[3] = 0xffff;
944 			break;
945 		} else {
946 			hash = ether_crc32_le(enm->enm_addrlo, ETHER_ADDR_LEN) & 0x3F;
947 			af[(uint16_t)(hash>>4)] |= (uint16_t)(1 << (hash % 16));
948 			ETHER_NEXT_MULTI(step, enm);
949 		}
950 	}
951 
952 	/* Write the multicast address filter */
953 	for(i=0; i<4; i++) {
954 		dme_write(sc, DM9000_MAB0+i*2, af[i] & 0xFF);
955 		dme_write(sc, DM9000_MAB0+i*2+1, (af[i] >> 8) & 0xFF);
956 	}
957 
958 	/* Setup RX controls */
959 	dme_write(sc, DM9000_RCR, DM9000_RCR_RXEN | DM9000_RCR_WTDIS);
960 }
961 
962 int
963 dme_pkt_write_2(struct dme_softc *sc, struct mbuf *bufChain)
964 {
965 	int left_over_count = 0; /* Number of bytes from previous mbuf, which
966 				    need to be written with the next.*/
967 	uint16_t left_over_buf = 0;
968 	int length = 0;
969 	struct mbuf *buf;
970 	uint8_t *write_ptr;
971 
972 	/* We expect that the DM9000 has been setup to accept writes before
973 	   this function is called. */
974 
975 	for (buf = bufChain; buf != NULL; buf = buf->m_next) {
976 		int to_write = buf->m_len;
977 
978 		length += to_write;
979 
980 		write_ptr = buf->m_data;
981 		while (to_write > 0 ||
982 		       (buf->m_next == NULL && left_over_count > 0)
983 		       ) {
984 			if (left_over_count > 0) {
985 				uint8_t b = 0;
986 				DPRINTF(("dme_pkt_write_16: "
987 					 "Writing left over byte\n"));
988 
989 				if (to_write > 0) {
990 					b = *write_ptr;
991 					to_write--;
992 					write_ptr++;
993 
994 					DPRINTF(("Took single byte\n"));
995 				} else {
996 					DPRINTF(("Leftover in last run\n"));
997 					length++;
998 				}
999 
1000 				/* Does shift direction depend on endianess? */
1001 				left_over_buf = left_over_buf | (b << 8);
1002 
1003 				bus_space_write_2(sc->sc_iot, sc->sc_ioh,
1004 						  sc->dme_data, left_over_buf);
1005 				TX_DATA_DPRINTF(("%02X ", left_over_buf));
1006 				left_over_count = 0;
1007 			} else if ((long)write_ptr % 2 != 0) {
1008 				/* Misaligned data */
1009 				DPRINTF(("dme_pkt_write_16: "
1010 					 "Detected misaligned data\n"));
1011 				left_over_buf = *write_ptr;
1012 				left_over_count = 1;
1013 				write_ptr++;
1014 				to_write--;
1015 			} else {
1016 				int i;
1017 				uint16_t *dptr = (uint16_t *)write_ptr;
1018 
1019 				/* A block of aligned data. */
1020 				for(i = 0; i < to_write / 2; i++) {
1021 					/* buf will be half-word aligned
1022 					 * all the time
1023 					 */
1024 					bus_space_write_2(sc->sc_iot,
1025 					    sc->sc_ioh, sc->dme_data, *dptr);
1026 					TX_DATA_DPRINTF(("%02X %02X ",
1027 					    *dptr & 0xFF, (*dptr >> 8) & 0xFF));
1028 					dptr++;
1029 				}
1030 
1031 				write_ptr += i * 2;
1032 				if (to_write % 2 != 0) {
1033 					DPRINTF(("dme_pkt_write_16: "
1034 						 "to_write %% 2: %d\n",
1035 						 to_write % 2));
1036 					left_over_count = 1;
1037 					/* XXX: Does this depend on
1038 					 * the endianess?
1039 					 */
1040 					left_over_buf = *write_ptr;
1041 
1042 					write_ptr++;
1043 					to_write--;
1044 					DPRINTF(("dme_pkt_write_16: "
1045 						 "to_write (after): %d\n",
1046 						 to_write));
1047 					DPRINTF(("dme_pkt_write_16: i * 2: %d\n",
1048 						 i*2));
1049 				}
1050 				to_write -= i * 2;
1051 			}
1052 		} /* while(...) */
1053 	} /* for(...) */
1054 
1055 	return length;
1056 }
1057 
1058 int
1059 dme_pkt_read_2(struct dme_softc *sc, struct ifnet *ifp, struct mbuf **outBuf)
1060 {
1061 	uint8_t rx_status;
1062 	struct mbuf *m;
1063 	uint16_t data;
1064 	uint16_t frame_length;
1065 	uint16_t i;
1066 	uint16_t *buf;
1067 
1068 	data = bus_space_read_2(sc->sc_iot, sc->sc_ioh, sc->dme_data);
1069 
1070 	rx_status = data & 0xFF;
1071 	frame_length = bus_space_read_2(sc->sc_iot,
1072 					sc->sc_ioh, sc->dme_data);
1073 	if (frame_length > ETHER_MAX_LEN) {
1074 		printf("Got frame of length: %d\n", frame_length);
1075 		printf("ETHER_MAX_LEN is: %d\n", ETHER_MAX_LEN);
1076 		panic("Something is rotten");
1077 	}
1078 	RX_DPRINTF(("dme_receive: "
1079 		    "rx_statux: 0x%x, frame_length: %d\n",
1080 		    rx_status, frame_length));
1081 
1082 
1083 	m = dme_alloc_receive_buffer(ifp, frame_length);
1084 	if (m == NULL) {
1085 		/*
1086 		 * didn't get a receive buffer, so we read the rest of the
1087 		 * packet, throw it away and return an error
1088 		 */
1089 		for (i = 0; i < frame_length; i += 2 ) {
1090 			data = bus_space_read_2(sc->sc_iot,
1091 					sc->sc_ioh, sc->dme_data);
1092 		}
1093 		*outBuf = NULL;
1094 		return 0;
1095 	}
1096 
1097 	buf = mtod(m, uint16_t*);
1098 
1099 	RX_DPRINTF(("dme_receive: "));
1100 
1101 	for (i = 0; i < frame_length; i += 2 ) {
1102 		data = bus_space_read_2(sc->sc_iot,
1103 					sc->sc_ioh, sc->dme_data);
1104 		if ( (frame_length % 2 != 0) &&
1105 		     (i == frame_length - 1) ) {
1106 			data = data & 0xff;
1107 			RX_DPRINTF((" L "));
1108 		}
1109 		*buf = data;
1110 		buf++;
1111 		RX_DATA_DPRINTF(("%02X %02X ", data & 0xff,
1112 				 (data >> 8) & 0xff));
1113 	}
1114 
1115 	RX_DATA_DPRINTF(("\n"));
1116 	RX_DPRINTF(("Read %d bytes\n", i));
1117 
1118 	*outBuf = m;
1119 	return rx_status;
1120 }
1121 
1122 int
1123 dme_pkt_write_1(struct dme_softc *sc, struct mbuf *bufChain)
1124 {
1125 	int length = 0, i;
1126 	struct mbuf *buf;
1127 	uint8_t *write_ptr;
1128 
1129 	/* We expect that the DM9000 has been setup to accept writes before
1130 	   this function is called. */
1131 
1132 	for (buf = bufChain; buf != NULL; buf = buf->m_next) {
1133 		int to_write = buf->m_len;
1134 
1135 		length += to_write;
1136 
1137 		write_ptr = buf->m_data;
1138 		for (i = 0; i < to_write; i++) {
1139 			bus_space_write_1(sc->sc_iot, sc->sc_ioh,
1140 			    sc->dme_data, *write_ptr);
1141 			write_ptr++;
1142 		}
1143 	} /* for(...) */
1144 
1145 	return length;
1146 }
1147 
1148 int
1149 dme_pkt_read_1(struct dme_softc *sc, struct ifnet *ifp, struct mbuf **outBuf)
1150 {
1151 	uint8_t rx_status;
1152 	struct mbuf *m;
1153 	uint8_t *buf;
1154 	uint16_t frame_length;
1155 	uint16_t i, reg;
1156 	uint8_t data;
1157 
1158 	reg = bus_space_read_1(sc->sc_iot, sc->sc_ioh, sc->dme_data);
1159 	reg |= bus_space_read_1(sc->sc_iot, sc->sc_ioh, sc->dme_data) << 8;
1160 	rx_status = reg & 0xFF;
1161 
1162 	reg = bus_space_read_1(sc->sc_iot, sc->sc_ioh, sc->dme_data);
1163 	reg |= bus_space_read_1(sc->sc_iot, sc->sc_ioh, sc->dme_data) << 8;
1164 	frame_length = reg;
1165 
1166 	if (frame_length > ETHER_MAX_LEN) {
1167 		printf("Got frame of length: %d\n", frame_length);
1168 		printf("ETHER_MAX_LEN is: %d\n", ETHER_MAX_LEN);
1169 		panic("Something is rotten");
1170 	}
1171 	RX_DPRINTF(("dme_receive: "
1172 		    "rx_statux: 0x%x, frame_length: %d\n",
1173 		    rx_status, frame_length));
1174 
1175 
1176 	m = dme_alloc_receive_buffer(ifp, frame_length);
1177 	if (m == NULL) {
1178 		/*
1179 		 * didn't get a receive buffer, so we read the rest of the
1180 		 * packet, throw it away and return an error
1181 		 */
1182 		for (i = 0; i < frame_length; i++ ) {
1183 			data = bus_space_read_2(sc->sc_iot,
1184 					sc->sc_ioh, sc->dme_data);
1185 		}
1186 		*outBuf = NULL;
1187 		return 0;
1188 	}
1189 
1190 	buf = mtod(m, uint8_t *);
1191 
1192 	RX_DPRINTF(("dme_receive: "));
1193 
1194 	for (i = 0; i< frame_length; i += 1 ) {
1195 		data = bus_space_read_1(sc->sc_iot, sc->sc_ioh, sc->dme_data);
1196 		*buf = data;
1197 		buf++;
1198 		RX_DATA_DPRINTF(("%02X ", data));
1199 	}
1200 
1201 	RX_DATA_DPRINTF(("\n"));
1202 	RX_DPRINTF(("Read %d bytes\n", i));
1203 
1204 	*outBuf = m;
1205 	return rx_status;
1206 }
1207 
1208 struct mbuf*
1209 dme_alloc_receive_buffer(struct ifnet *ifp, unsigned int frame_length)
1210 {
1211 	struct dme_softc *sc = ifp->if_softc;
1212 	struct mbuf *m;
1213 	int pad;
1214 
1215 	MGETHDR(m, M_DONTWAIT, MT_DATA);
1216 	if (m == NULL) return NULL;
1217 
1218 	m_set_rcvif(m, ifp);
1219 	/* Ensure that we always allocate an even number of
1220 	 * bytes in order to avoid writing beyond the buffer
1221 	 */
1222 	m->m_pkthdr.len = frame_length + (frame_length % sc->sc_data_width);
1223 	pad = ALIGN(sizeof(struct ether_header)) -
1224 		sizeof(struct ether_header);
1225 	/* All our frames have the CRC attached */
1226 	m->m_flags |= M_HASFCS;
1227 	if (m->m_pkthdr.len + pad > MHLEN) {
1228 		MCLGET(m, M_DONTWAIT);
1229 		if ((m->m_flags & M_EXT) == 0) {
1230 			m_freem(m);
1231 			return NULL;
1232 		}
1233 	}
1234 
1235 	m->m_data += pad;
1236 	m->m_len = frame_length + (frame_length % sc->sc_data_width);
1237 
1238 	return m;
1239 }
1240