xref: /netbsd-src/sys/dev/ic/smc83c170.c (revision bcc8ec9959e7b01e313d813067bfb43a3ad70551)
1 /*	$NetBSD: smc83c170.c,v 1.41 2000/12/19 00:06:02 thorpej Exp $	*/
2 
3 /*-
4  * Copyright (c) 1998, 1999 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
9  * 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  * 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 NetBSD
22  *	Foundation, Inc. and its contributors.
23  * 4. Neither the name of The NetBSD Foundation nor the names of its
24  *    contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37  * POSSIBILITY OF SUCH DAMAGE.
38  */
39 
40 /*
41  * Device driver for the Standard Microsystems Corp. 83C170
42  * Ethernet PCI Integrated Controller (EPIC/100).
43  */
44 
45 #include "opt_inet.h"
46 #include "opt_ns.h"
47 #include "bpfilter.h"
48 
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/callout.h>
52 #include <sys/mbuf.h>
53 #include <sys/malloc.h>
54 #include <sys/kernel.h>
55 #include <sys/socket.h>
56 #include <sys/ioctl.h>
57 #include <sys/errno.h>
58 #include <sys/device.h>
59 
60 #include <uvm/uvm_extern.h>
61 
62 #include <net/if.h>
63 #include <net/if_dl.h>
64 #include <net/if_media.h>
65 #include <net/if_ether.h>
66 
67 #if NBPFILTER > 0
68 #include <net/bpf.h>
69 #endif
70 
71 #ifdef INET
72 #include <netinet/in.h>
73 #include <netinet/if_inarp.h>
74 #endif
75 
76 #ifdef NS
77 #include <netns/ns.h>
78 #include <netns/ns_if.h>
79 #endif
80 
81 #include <machine/bus.h>
82 #include <machine/intr.h>
83 
84 #include <dev/mii/miivar.h>
85 
86 #include <dev/ic/smc83c170reg.h>
87 #include <dev/ic/smc83c170var.h>
88 
89 void	epic_start __P((struct ifnet *));
90 void	epic_watchdog __P((struct ifnet *));
91 int	epic_ioctl __P((struct ifnet *, u_long, caddr_t));
92 int	epic_init __P((struct ifnet *));
93 void	epic_stop __P((struct ifnet *, int));
94 
95 void	epic_shutdown __P((void *));
96 
97 void	epic_reset __P((struct epic_softc *));
98 void	epic_rxdrain __P((struct epic_softc *));
99 int	epic_add_rxbuf __P((struct epic_softc *, int));
100 void	epic_read_eeprom __P((struct epic_softc *, int, int, u_int16_t *));
101 void	epic_set_mchash __P((struct epic_softc *));
102 void	epic_fixup_clock_source __P((struct epic_softc *));
103 int	epic_mii_read __P((struct device *, int, int));
104 void	epic_mii_write __P((struct device *, int, int, int));
105 int	epic_mii_wait __P((struct epic_softc *, u_int32_t));
106 void	epic_tick __P((void *));
107 
108 void	epic_statchg __P((struct device *));
109 int	epic_mediachange __P((struct ifnet *));
110 void	epic_mediastatus __P((struct ifnet *, struct ifmediareq *));
111 
112 #define	INTMASK	(INTSTAT_FATAL_INT | INTSTAT_TXU | \
113 	    INTSTAT_TXC | INTSTAT_RXE | INTSTAT_RQE | INTSTAT_RCC)
114 
115 int	epic_copy_small = 0;
116 
117 /*
118  * Attach an EPIC interface to the system.
119  */
120 void
121 epic_attach(sc)
122 	struct epic_softc *sc;
123 {
124 	bus_space_tag_t st = sc->sc_st;
125 	bus_space_handle_t sh = sc->sc_sh;
126 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
127 	int i, rseg, error;
128 	bus_dma_segment_t seg;
129 	u_int8_t enaddr[ETHER_ADDR_LEN], devname[12 + 1];
130 	u_int16_t myea[ETHER_ADDR_LEN / 2], mydevname[6];
131 
132 	callout_init(&sc->sc_mii_callout);
133 
134 	/*
135 	 * Allocate the control data structures, and create and load the
136 	 * DMA map for it.
137 	 */
138 	if ((error = bus_dmamem_alloc(sc->sc_dmat,
139 	    sizeof(struct epic_control_data), PAGE_SIZE, 0, &seg, 1, &rseg,
140 	    BUS_DMA_NOWAIT)) != 0) {
141 		printf("%s: unable to allocate control data, error = %d\n",
142 		    sc->sc_dev.dv_xname, error);
143 		goto fail_0;
144 	}
145 
146 	if ((error = bus_dmamem_map(sc->sc_dmat, &seg, rseg,
147 	    sizeof(struct epic_control_data), (caddr_t *)&sc->sc_control_data,
148 	    BUS_DMA_NOWAIT|BUS_DMA_COHERENT)) != 0) {
149 		printf("%s: unable to map control data, error = %d\n",
150 		    sc->sc_dev.dv_xname, error);
151 		goto fail_1;
152 	}
153 
154 	if ((error = bus_dmamap_create(sc->sc_dmat,
155 	    sizeof(struct epic_control_data), 1,
156 	    sizeof(struct epic_control_data), 0, BUS_DMA_NOWAIT,
157 	    &sc->sc_cddmamap)) != 0) {
158 		printf("%s: unable to create control data DMA map, "
159 		    "error = %d\n", sc->sc_dev.dv_xname, error);
160 		goto fail_2;
161 	}
162 
163 	if ((error = bus_dmamap_load(sc->sc_dmat, sc->sc_cddmamap,
164 	    sc->sc_control_data, sizeof(struct epic_control_data), NULL,
165 	    BUS_DMA_NOWAIT)) != 0) {
166 		printf("%s: unable to load control data DMA map, error = %d\n",
167 		    sc->sc_dev.dv_xname, error);
168 		goto fail_3;
169 	}
170 
171 	/*
172 	 * Create the transmit buffer DMA maps.
173 	 */
174 	for (i = 0; i < EPIC_NTXDESC; i++) {
175 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES,
176 		    EPIC_NFRAGS, MCLBYTES, 0, BUS_DMA_NOWAIT,
177 		    &EPIC_DSTX(sc, i)->ds_dmamap)) != 0) {
178 			printf("%s: unable to create tx DMA map %d, "
179 			    "error = %d\n", sc->sc_dev.dv_xname, i, error);
180 			goto fail_4;
181 		}
182 	}
183 
184 	/*
185 	 * Create the recieve buffer DMA maps.
186 	 */
187 	for (i = 0; i < EPIC_NRXDESC; i++) {
188 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES, 1,
189 		    MCLBYTES, 0, BUS_DMA_NOWAIT,
190 		    &EPIC_DSRX(sc, i)->ds_dmamap)) != 0) {
191 			printf("%s: unable to create rx DMA map %d, "
192 			    "error = %d\n", sc->sc_dev.dv_xname, i, error);
193 			goto fail_5;
194 		}
195 		EPIC_DSRX(sc, i)->ds_mbuf = NULL;
196 	}
197 
198 
199 	/*
200 	 * Bring the chip out of low-power mode and reset it to a known state.
201 	 */
202 	bus_space_write_4(st, sh, EPIC_GENCTL, 0);
203 	epic_reset(sc);
204 
205 	/*
206 	 * Read the Ethernet address from the EEPROM.
207 	 */
208 	epic_read_eeprom(sc, 0, (sizeof(myea) / sizeof(myea[0])), myea);
209 	for (i = 0; i < sizeof(myea)/ sizeof(myea[0]); i++) {
210 		enaddr[i * 2]     = myea[i] & 0xff;
211 		enaddr[i * 2 + 1] = myea[i] >> 8;
212 	}
213 
214 	/*
215 	 * ...and the device name.
216 	 */
217 	epic_read_eeprom(sc, 0x2c, (sizeof(mydevname) / sizeof(mydevname[0])),
218 	    mydevname);
219 	for (i = 0; i < sizeof(mydevname) / sizeof(mydevname[0]); i++) {
220 		devname[i * 2]     = mydevname[i] & 0xff;
221 		devname[i * 2 + 1] = mydevname[i] >> 8;
222 	}
223 
224 	devname[sizeof(mydevname)] = '\0';
225 	for (i = sizeof(mydevname) - 1; i >= 0; i--) {
226 		if (devname[i] == ' ')
227 			devname[i] = '\0';
228 		else
229 			break;
230 	}
231 
232 	printf("%s: %s, Ethernet address %s\n", sc->sc_dev.dv_xname,
233 	    devname, ether_sprintf(enaddr));
234 
235 	/*
236 	 * Initialize our media structures and probe the MII.
237 	 */
238 	sc->sc_mii.mii_ifp = ifp;
239 	sc->sc_mii.mii_readreg = epic_mii_read;
240 	sc->sc_mii.mii_writereg = epic_mii_write;
241 	sc->sc_mii.mii_statchg = epic_statchg;
242 	ifmedia_init(&sc->sc_mii.mii_media, 0, epic_mediachange,
243 	    epic_mediastatus);
244 	mii_attach(&sc->sc_dev, &sc->sc_mii, 0xffffffff, MII_PHY_ANY,
245 	    MII_OFFSET_ANY, 0);
246 	if (LIST_FIRST(&sc->sc_mii.mii_phys) == NULL) {
247 		ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE, 0, NULL);
248 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE);
249 	} else
250 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_AUTO);
251 
252 	strcpy(ifp->if_xname, sc->sc_dev.dv_xname);
253 	ifp->if_softc = sc;
254 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
255 	ifp->if_ioctl = epic_ioctl;
256 	ifp->if_start = epic_start;
257 	ifp->if_watchdog = epic_watchdog;
258 	ifp->if_init = epic_init;
259 	ifp->if_stop = epic_stop;
260 	IFQ_SET_READY(&ifp->if_snd);
261 
262 	/*
263 	 * We can support 802.1Q VLAN-sized frames.
264 	 */
265 	sc->sc_ethercom.ec_capabilities |= ETHERCAP_VLAN_MTU;
266 
267 	/*
268 	 * Attach the interface.
269 	 */
270 	if_attach(ifp);
271 	ether_ifattach(ifp, enaddr);
272 
273 	/*
274 	 * Make sure the interface is shutdown during reboot.
275 	 */
276 	sc->sc_sdhook = shutdownhook_establish(epic_shutdown, sc);
277 	if (sc->sc_sdhook == NULL)
278 		printf("%s: WARNING: unable to establish shutdown hook\n",
279 		    sc->sc_dev.dv_xname);
280 	return;
281 
282 	/*
283 	 * Free any resources we've allocated during the failed attach
284 	 * attempt.  Do this in reverse order and fall through.
285 	 */
286  fail_5:
287 	for (i = 0; i < EPIC_NRXDESC; i++) {
288 		if (EPIC_DSRX(sc, i)->ds_dmamap != NULL)
289 			bus_dmamap_destroy(sc->sc_dmat,
290 			    EPIC_DSRX(sc, i)->ds_dmamap);
291 	}
292  fail_4:
293 	for (i = 0; i < EPIC_NTXDESC; i++) {
294 		if (EPIC_DSTX(sc, i)->ds_dmamap != NULL)
295 			bus_dmamap_destroy(sc->sc_dmat,
296 			    EPIC_DSTX(sc, i)->ds_dmamap);
297 	}
298 	bus_dmamap_unload(sc->sc_dmat, sc->sc_cddmamap);
299  fail_3:
300 	bus_dmamap_destroy(sc->sc_dmat, sc->sc_cddmamap);
301  fail_2:
302 	bus_dmamem_unmap(sc->sc_dmat, (caddr_t)sc->sc_control_data,
303 	    sizeof(struct epic_control_data));
304  fail_1:
305 	bus_dmamem_free(sc->sc_dmat, &seg, rseg);
306  fail_0:
307 	return;
308 }
309 
310 /*
311  * Shutdown hook.  Make sure the interface is stopped at reboot.
312  */
313 void
314 epic_shutdown(arg)
315 	void *arg;
316 {
317 	struct epic_softc *sc = arg;
318 
319 	epic_stop(&sc->sc_ethercom.ec_if, 1);
320 }
321 
322 /*
323  * Start packet transmission on the interface.
324  * [ifnet interface function]
325  */
326 void
327 epic_start(ifp)
328 	struct ifnet *ifp;
329 {
330 	struct epic_softc *sc = ifp->if_softc;
331 	struct mbuf *m0, *m;
332 	struct epic_txdesc *txd;
333 	struct epic_descsoft *ds;
334 	struct epic_fraglist *fr;
335 	bus_dmamap_t dmamap;
336 	int error, firsttx, nexttx, opending, seg;
337 
338 	/*
339 	 * Remember the previous txpending and the first transmit
340 	 * descriptor we use.
341 	 */
342 	opending = sc->sc_txpending;
343 	firsttx = EPIC_NEXTTX(sc->sc_txlast);
344 
345 	/*
346 	 * Loop through the send queue, setting up transmit descriptors
347 	 * until we drain the queue, or use up all available transmit
348 	 * descriptors.
349 	 */
350 	while (sc->sc_txpending < EPIC_NTXDESC) {
351 		/*
352 		 * Grab a packet off the queue.
353 		 */
354 		IFQ_POLL(&ifp->if_snd, m0);
355 		if (m0 == NULL)
356 			break;
357 		m = NULL;
358 
359 		/*
360 		 * Get the last and next available transmit descriptor.
361 		 */
362 		nexttx = EPIC_NEXTTX(sc->sc_txlast);
363 		txd = EPIC_CDTX(sc, nexttx);
364 		fr = EPIC_CDFL(sc, nexttx);
365 		ds = EPIC_DSTX(sc, nexttx);
366 		dmamap = ds->ds_dmamap;
367 
368 		/*
369 		 * Load the DMA map.  If this fails, the packet either
370 		 * didn't fit in the alloted number of frags, or we were
371 		 * short on resources.  In this case, we'll copy and try
372 		 * again.
373 		 */
374 		if (bus_dmamap_load_mbuf(sc->sc_dmat, dmamap, m0,
375 		    BUS_DMA_NOWAIT) != 0) {
376 			MGETHDR(m, M_DONTWAIT, MT_DATA);
377 			if (m == NULL) {
378 				printf("%s: unable to allocate Tx mbuf\n",
379 				    sc->sc_dev.dv_xname);
380 				break;
381 			}
382 			if (m0->m_pkthdr.len > MHLEN) {
383 				MCLGET(m, M_DONTWAIT);
384 				if ((m->m_flags & M_EXT) == 0) {
385 					printf("%s: unable to allocate Tx "
386 					    "cluster\n", sc->sc_dev.dv_xname);
387 					m_freem(m);
388 					break;
389 				}
390 			}
391 			m_copydata(m0, 0, m0->m_pkthdr.len, mtod(m, caddr_t));
392 			m->m_pkthdr.len = m->m_len = m0->m_pkthdr.len;
393 			error = bus_dmamap_load_mbuf(sc->sc_dmat, dmamap,
394 			    m, BUS_DMA_NOWAIT);
395 			if (error) {
396 				printf("%s: unable to load Tx buffer, "
397 				    "error = %d\n", sc->sc_dev.dv_xname, error);
398 				break;
399 			}
400 		}
401 		IFQ_DEQUEUE(&ifp->if_snd, m0);
402 		if (m != NULL) {
403 			m_freem(m0);
404 			m0 = m;
405 		}
406 
407 		/* Initialize the fraglist. */
408 		fr->ef_nfrags = dmamap->dm_nsegs;
409 		for (seg = 0; seg < dmamap->dm_nsegs; seg++) {
410 			fr->ef_frags[seg].ef_addr =
411 			    dmamap->dm_segs[seg].ds_addr;
412 			fr->ef_frags[seg].ef_length =
413 			    dmamap->dm_segs[seg].ds_len;
414 		}
415 
416 		EPIC_CDFLSYNC(sc, nexttx, BUS_DMASYNC_PREWRITE);
417 
418 		/* Sync the DMA map. */
419 		bus_dmamap_sync(sc->sc_dmat, dmamap, 0, dmamap->dm_mapsize,
420 		    BUS_DMASYNC_PREWRITE);
421 
422 		/*
423 		 * Store a pointer to the packet so we can free it later.
424 		 */
425 		ds->ds_mbuf = m0;
426 
427 		/*
428 		 * Fill in the transmit descriptor.  The EPIC doesn't
429 		 * auto-pad, so we have to do this ourselves.
430 		 */
431 		txd->et_control = ET_TXCTL_LASTDESC | ET_TXCTL_FRAGLIST;
432 		txd->et_txlength = max(m0->m_pkthdr.len,
433 		    ETHER_MIN_LEN - ETHER_CRC_LEN);
434 
435 		/*
436 		 * If this is the first descriptor we're enqueueing,
437 		 * don't give it to the EPIC yet.  That could cause
438 		 * a race condition.  We'll do it below.
439 		 */
440 		if (nexttx == firsttx)
441 			txd->et_txstatus = 0;
442 		else
443 			txd->et_txstatus = ET_TXSTAT_OWNER;
444 
445 		EPIC_CDTXSYNC(sc, nexttx,
446 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
447 
448 		/* Advance the tx pointer. */
449 		sc->sc_txpending++;
450 		sc->sc_txlast = nexttx;
451 
452 #if NBPFILTER > 0
453 		/*
454 		 * Pass the packet to any BPF listeners.
455 		 */
456 		if (ifp->if_bpf)
457 			bpf_mtap(ifp->if_bpf, m0);
458 #endif
459 	}
460 
461 	if (sc->sc_txpending == EPIC_NTXDESC) {
462 		/* No more slots left; notify upper layer. */
463 		ifp->if_flags |= IFF_OACTIVE;
464 	}
465 
466 	if (sc->sc_txpending != opending) {
467 		/*
468 		 * We enqueued packets.  If the transmitter was idle,
469 		 * reset the txdirty pointer.
470 		 */
471 		if (opending == 0)
472 			sc->sc_txdirty = firsttx;
473 
474 		/*
475 		 * Cause a transmit interrupt to happen on the
476 		 * last packet we enqueued.
477 		 */
478 		EPIC_CDTX(sc, sc->sc_txlast)->et_control |= ET_TXCTL_IAF;
479 		EPIC_CDTXSYNC(sc, sc->sc_txlast,
480 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
481 
482 		/*
483 		 * The entire packet chain is set up.  Give the
484 		 * first descriptor to the EPIC now.
485 		 */
486 		EPIC_CDTX(sc, firsttx)->et_txstatus = ET_TXSTAT_OWNER;
487 		EPIC_CDTXSYNC(sc, firsttx,
488 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
489 
490 		/* Start the transmitter. */
491 		bus_space_write_4(sc->sc_st, sc->sc_sh, EPIC_COMMAND,
492 		    COMMAND_TXQUEUED);
493 
494 		/* Set a watchdog timer in case the chip flakes out. */
495 		ifp->if_timer = 5;
496 	}
497 }
498 
499 /*
500  * Watchdog timer handler.
501  * [ifnet interface function]
502  */
503 void
504 epic_watchdog(ifp)
505 	struct ifnet *ifp;
506 {
507 	struct epic_softc *sc = ifp->if_softc;
508 
509 	printf("%s: device timeout\n", sc->sc_dev.dv_xname);
510 	ifp->if_oerrors++;
511 
512 	(void) epic_init(ifp);
513 }
514 
515 /*
516  * Handle control requests from the operator.
517  * [ifnet interface function]
518  */
519 int
520 epic_ioctl(ifp, cmd, data)
521 	struct ifnet *ifp;
522 	u_long cmd;
523 	caddr_t data;
524 {
525 	struct epic_softc *sc = ifp->if_softc;
526 	struct ifreq *ifr = (struct ifreq *)data;
527 	int s, error;
528 
529 	s = splnet();
530 
531 	switch (cmd) {
532 	case SIOCSIFMEDIA:
533 	case SIOCGIFMEDIA:
534 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii.mii_media, cmd);
535 		break;
536 
537 	default:
538 		error = ether_ioctl(ifp, cmd, data);
539 		if (error == ENETRESET) {
540 			/*
541 			 * Multicast list has changed; set the hardware filter
542 			 * accordingly.  Update our idea of the current media;
543 			 * epic_set_mchash() needs to know what it is.
544 			 */
545 			mii_pollstat(&sc->sc_mii);
546 			epic_set_mchash(sc);
547 			error = 0;
548 		}
549 		break;
550 	}
551 
552 	splx(s);
553 	return (error);
554 }
555 
556 /*
557  * Interrupt handler.
558  */
559 int
560 epic_intr(arg)
561 	void *arg;
562 {
563 	struct epic_softc *sc = arg;
564 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
565 	struct epic_rxdesc *rxd;
566 	struct epic_txdesc *txd;
567 	struct epic_descsoft *ds;
568 	struct mbuf *m;
569 	u_int32_t intstat;
570 	int i, len, claimed = 0;
571 
572  top:
573 	/*
574 	 * Get the interrupt status from the EPIC.
575 	 */
576 	intstat = bus_space_read_4(sc->sc_st, sc->sc_sh, EPIC_INTSTAT);
577 	if ((intstat & INTSTAT_INT_ACTV) == 0)
578 		return (claimed);
579 
580 	claimed = 1;
581 
582 	/*
583 	 * Acknowledge the interrupt.
584 	 */
585 	bus_space_write_4(sc->sc_st, sc->sc_sh, EPIC_INTSTAT,
586 	    intstat & INTMASK);
587 
588 	/*
589 	 * Check for receive interrupts.
590 	 */
591 	if (intstat & (INTSTAT_RCC | INTSTAT_RXE | INTSTAT_RQE)) {
592 		for (i = sc->sc_rxptr;; i = EPIC_NEXTRX(i)) {
593 			rxd = EPIC_CDRX(sc, i);
594 			ds = EPIC_DSRX(sc, i);
595 
596 			EPIC_CDRXSYNC(sc, i,
597 			    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
598 
599 			if (rxd->er_rxstatus & ER_RXSTAT_OWNER) {
600 				/*
601 				 * We have processed all of the
602 				 * receive buffers.
603 				 */
604 				break;
605 			}
606 
607 			/*
608 			 * Make sure the packet arrived intact.  If an error
609 			 * occurred, update stats and reset the descriptor.
610 			 * The buffer will be reused the next time the
611 			 * descriptor comes up in the ring.
612 			 */
613 			if ((rxd->er_rxstatus & ER_RXSTAT_PKTINTACT) == 0) {
614 				if (rxd->er_rxstatus & ER_RXSTAT_CRCERROR)
615 					printf("%s: CRC error\n",
616 					    sc->sc_dev.dv_xname);
617 				if (rxd->er_rxstatus & ER_RXSTAT_ALIGNERROR)
618 					printf("%s: alignment error\n",
619 					    sc->sc_dev.dv_xname);
620 				ifp->if_ierrors++;
621 				EPIC_INIT_RXDESC(sc, i);
622 				continue;
623 			}
624 
625 			bus_dmamap_sync(sc->sc_dmat, ds->ds_dmamap, 0,
626 			    ds->ds_dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);
627 
628 			/*
629 			 * The EPIC includes the CRC with every packet.
630 			 */
631 			len = rxd->er_rxlength;
632 
633 			if (len < sizeof(struct ether_header)) {
634 				/*
635 				 * Runt packet; drop it now.
636 				 */
637 				ifp->if_ierrors++;
638 				EPIC_INIT_RXDESC(sc, i);
639 				bus_dmamap_sync(sc->sc_dmat, ds->ds_dmamap, 0,
640 				    ds->ds_dmamap->dm_mapsize,
641 				    BUS_DMASYNC_PREREAD);
642 				continue;
643 			}
644 
645 			/*
646 			 * If the packet is small enough to fit in a
647 			 * single header mbuf, allocate one and copy
648 			 * the data into it.  This greatly reduces
649 			 * memory consumption when we receive lots
650 			 * of small packets.
651 			 *
652 			 * Otherwise, we add a new buffer to the receive
653 			 * chain.  If this fails, we drop the packet and
654 			 * recycle the old buffer.
655 			 */
656 			if (epic_copy_small != 0 && len <= MHLEN) {
657 				MGETHDR(m, M_DONTWAIT, MT_DATA);
658 				if (m == NULL)
659 					goto dropit;
660 				memcpy(mtod(m, caddr_t),
661 				    mtod(ds->ds_mbuf, caddr_t), len);
662 				EPIC_INIT_RXDESC(sc, i);
663 				bus_dmamap_sync(sc->sc_dmat, ds->ds_dmamap, 0,
664 				    ds->ds_dmamap->dm_mapsize,
665 				    BUS_DMASYNC_PREREAD);
666 			} else {
667 				m = ds->ds_mbuf;
668 				if (epic_add_rxbuf(sc, i) != 0) {
669  dropit:
670 					ifp->if_ierrors++;
671 					EPIC_INIT_RXDESC(sc, i);
672 					bus_dmamap_sync(sc->sc_dmat,
673 					    ds->ds_dmamap, 0,
674 					    ds->ds_dmamap->dm_mapsize,
675 					    BUS_DMASYNC_PREREAD);
676 					continue;
677 				}
678 			}
679 
680 			m->m_flags |= M_HASFCS;
681 			m->m_pkthdr.rcvif = ifp;
682 			m->m_pkthdr.len = m->m_len = len;
683 
684 #if NBPFILTER > 0
685 			/*
686 			 * Pass this up to any BPF listeners, but only
687 			 * pass it up the stack if its for us.
688 			 */
689 			if (ifp->if_bpf)
690 				bpf_mtap(ifp->if_bpf, m);
691 #endif
692 
693 			/* Pass it on. */
694 			(*ifp->if_input)(ifp, m);
695 			ifp->if_ipackets++;
696 		}
697 
698 		/* Update the recieve pointer. */
699 		sc->sc_rxptr = i;
700 
701 		/*
702 		 * Check for receive queue underflow.
703 		 */
704 		if (intstat & INTSTAT_RQE) {
705 			printf("%s: receiver queue empty\n",
706 			    sc->sc_dev.dv_xname);
707 			/*
708 			 * Ring is already built; just restart the
709 			 * receiver.
710 			 */
711 			bus_space_write_4(sc->sc_st, sc->sc_sh, EPIC_PRCDAR,
712 			    EPIC_CDRXADDR(sc, sc->sc_rxptr));
713 			bus_space_write_4(sc->sc_st, sc->sc_sh, EPIC_COMMAND,
714 			    COMMAND_RXQUEUED | COMMAND_START_RX);
715 		}
716 	}
717 
718 	/*
719 	 * Check for transmission complete interrupts.
720 	 */
721 	if (intstat & (INTSTAT_TXC | INTSTAT_TXU)) {
722 		ifp->if_flags &= ~IFF_OACTIVE;
723 		for (i = sc->sc_txdirty; sc->sc_txpending != 0;
724 		     i = EPIC_NEXTTX(i), sc->sc_txpending--) {
725 			txd = EPIC_CDTX(sc, i);
726 			ds = EPIC_DSTX(sc, i);
727 
728 			EPIC_CDTXSYNC(sc, i,
729 			    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
730 
731 			if (txd->et_txstatus & ET_TXSTAT_OWNER)
732 				break;
733 
734 			EPIC_CDFLSYNC(sc, i, BUS_DMASYNC_POSTWRITE);
735 
736 			bus_dmamap_sync(sc->sc_dmat, ds->ds_dmamap,
737 			    0, ds->ds_dmamap->dm_mapsize,
738 			    BUS_DMASYNC_POSTWRITE);
739 			bus_dmamap_unload(sc->sc_dmat, ds->ds_dmamap);
740 			m_freem(ds->ds_mbuf);
741 			ds->ds_mbuf = NULL;
742 
743 			/*
744 			 * Check for errors and collisions.
745 			 */
746 			if ((txd->et_txstatus & ET_TXSTAT_PACKETTX) == 0)
747 				ifp->if_oerrors++;
748 			else
749 				ifp->if_opackets++;
750 			ifp->if_collisions +=
751 			    TXSTAT_COLLISIONS(txd->et_txstatus);
752 			if (txd->et_txstatus & ET_TXSTAT_CARSENSELOST)
753 				printf("%s: lost carrier\n",
754 				    sc->sc_dev.dv_xname);
755 		}
756 
757 		/* Update the dirty transmit buffer pointer. */
758 		sc->sc_txdirty = i;
759 
760 		/*
761 		 * Cancel the watchdog timer if there are no pending
762 		 * transmissions.
763 		 */
764 		if (sc->sc_txpending == 0)
765 			ifp->if_timer = 0;
766 
767 		/*
768 		 * Kick the transmitter after a DMA underrun.
769 		 */
770 		if (intstat & INTSTAT_TXU) {
771 			printf("%s: transmit underrun\n", sc->sc_dev.dv_xname);
772 			bus_space_write_4(sc->sc_st, sc->sc_sh,
773 			    EPIC_COMMAND, COMMAND_TXUGO);
774 			if (sc->sc_txpending)
775 				bus_space_write_4(sc->sc_st, sc->sc_sh,
776 				    EPIC_COMMAND, COMMAND_TXQUEUED);
777 		}
778 
779 		/*
780 		 * Try to get more packets going.
781 		 */
782 		epic_start(ifp);
783 	}
784 
785 	/*
786 	 * Check for fatal interrupts.
787 	 */
788 	if (intstat & INTSTAT_FATAL_INT) {
789 		if (intstat & INTSTAT_PTA)
790 			printf("%s: PCI target abort error\n",
791 			    sc->sc_dev.dv_xname);
792 		else if (intstat & INTSTAT_PMA)
793 			printf("%s: PCI master abort error\n",
794 			    sc->sc_dev.dv_xname);
795 		else if (intstat & INTSTAT_APE)
796 			printf("%s: PCI address parity error\n",
797 			    sc->sc_dev.dv_xname);
798 		else if (intstat & INTSTAT_DPE)
799 			printf("%s: PCI data parity error\n",
800 			    sc->sc_dev.dv_xname);
801 		else
802 			printf("%s: unknown fatal error\n",
803 			    sc->sc_dev.dv_xname);
804 		(void) epic_init(ifp);
805 	}
806 
807 	/*
808 	 * Check for more interrupts.
809 	 */
810 	goto top;
811 }
812 
813 /*
814  * One second timer, used to tick the MII.
815  */
816 void
817 epic_tick(arg)
818 	void *arg;
819 {
820 	struct epic_softc *sc = arg;
821 	int s;
822 
823 	s = splnet();
824 	mii_tick(&sc->sc_mii);
825 	splx(s);
826 
827 	callout_reset(&sc->sc_mii_callout, hz, epic_tick, sc);
828 }
829 
830 /*
831  * Fixup the clock source on the EPIC.
832  */
833 void
834 epic_fixup_clock_source(sc)
835 	struct epic_softc *sc;
836 {
837 	int i;
838 
839 	/*
840 	 * According to SMC Application Note 7-15, the EPIC's clock
841 	 * source is incorrect following a reset.  This manifests itself
842 	 * as failure to recognize when host software has written to
843 	 * a register on the EPIC.  The appnote recommends issuing at
844 	 * least 16 consecutive writes to the CLOCK TEST bit to correctly
845 	 * configure the clock source.
846 	 */
847 	for (i = 0; i < 16; i++)
848 		bus_space_write_4(sc->sc_st, sc->sc_sh, EPIC_TEST,
849 		    TEST_CLOCKTEST);
850 }
851 
852 /*
853  * Perform a soft reset on the EPIC.
854  */
855 void
856 epic_reset(sc)
857 	struct epic_softc *sc;
858 {
859 
860 	epic_fixup_clock_source(sc);
861 
862 	bus_space_write_4(sc->sc_st, sc->sc_sh, EPIC_GENCTL, 0);
863 	delay(100);
864 	bus_space_write_4(sc->sc_st, sc->sc_sh, EPIC_GENCTL, GENCTL_SOFTRESET);
865 	delay(100);
866 
867 	epic_fixup_clock_source(sc);
868 }
869 
870 /*
871  * Initialize the interface.  Must be called at splnet().
872  */
873 int
874 epic_init(ifp)
875 	struct ifnet *ifp;
876 {
877 	struct epic_softc *sc = ifp->if_softc;
878 	bus_space_tag_t st = sc->sc_st;
879 	bus_space_handle_t sh = sc->sc_sh;
880 	u_int8_t *enaddr = LLADDR(ifp->if_sadl);
881 	struct epic_txdesc *txd;
882 	struct epic_descsoft *ds;
883 	u_int32_t genctl, reg0;
884 	int i, error = 0;
885 
886 	/*
887 	 * Cancel any pending I/O.
888 	 */
889 	epic_stop(ifp, 0);
890 
891 	/*
892 	 * Reset the EPIC to a known state.
893 	 */
894 	epic_reset(sc);
895 
896 	/*
897 	 * Magical mystery initialization.
898 	 */
899 	bus_space_write_4(st, sh, EPIC_TXTEST, 0);
900 
901 	/*
902 	 * Initialize the EPIC genctl register:
903 	 *
904 	 *	- 64 byte receive FIFO threshold
905 	 *	- automatic advance to next receive frame
906 	 */
907 	genctl = GENCTL_RX_FIFO_THRESH0 | GENCTL_ONECOPY;
908 #if BYTE_ORDER == BIG_ENDIAN
909 	genctl |= GENCTL_BIG_ENDIAN;
910 #endif
911 	bus_space_write_4(st, sh, EPIC_GENCTL, genctl);
912 
913 	/*
914 	 * Reset the MII bus and PHY.
915 	 */
916 	reg0 = bus_space_read_4(st, sh, EPIC_NVCTL);
917 	bus_space_write_4(st, sh, EPIC_NVCTL, reg0 | NVCTL_GPIO1 | NVCTL_GPOE1);
918 	bus_space_write_4(st, sh, EPIC_MIICFG, MIICFG_ENASER);
919 	bus_space_write_4(st, sh, EPIC_GENCTL, genctl | GENCTL_RESET_PHY);
920 	delay(100);
921 	bus_space_write_4(st, sh, EPIC_GENCTL, genctl);
922 	delay(100);
923 	bus_space_write_4(st, sh, EPIC_NVCTL, reg0);
924 
925 	/*
926 	 * Initialize Ethernet address.
927 	 */
928 	reg0 = enaddr[1] << 8 | enaddr[0];
929 	bus_space_write_4(st, sh, EPIC_LAN0, reg0);
930 	reg0 = enaddr[3] << 8 | enaddr[2];
931 	bus_space_write_4(st, sh, EPIC_LAN1, reg0);
932 	reg0 = enaddr[5] << 8 | enaddr[4];
933 	bus_space_write_4(st, sh, EPIC_LAN2, reg0);
934 
935 	/*
936 	 * Initialize receive control.  Remember the external buffer
937 	 * size setting.
938 	 */
939 	reg0 = bus_space_read_4(st, sh, EPIC_RXCON) &
940 	    (RXCON_EXTBUFSIZESEL1 | RXCON_EXTBUFSIZESEL0);
941 	reg0 |= (RXCON_RXMULTICAST | RXCON_RXBROADCAST);
942 	if (ifp->if_flags & IFF_PROMISC)
943 		reg0 |= RXCON_PROMISCMODE;
944 	bus_space_write_4(st, sh, EPIC_RXCON, reg0);
945 
946 	/* Set the current media. */
947 	mii_mediachg(&sc->sc_mii);
948 
949 	/* Set up the multicast hash table. */
950 	epic_set_mchash(sc);
951 
952 	/*
953 	 * Initialize the transmit descriptor ring.  txlast is initialized
954 	 * to the end of the list so that it will wrap around to the first
955 	 * descriptor when the first packet is transmitted.
956 	 */
957 	for (i = 0; i < EPIC_NTXDESC; i++) {
958 		txd = EPIC_CDTX(sc, i);
959 		memset(txd, 0, sizeof(struct epic_txdesc));
960 		txd->et_bufaddr = EPIC_CDFLADDR(sc, i);
961 		txd->et_nextdesc = EPIC_CDTXADDR(sc, EPIC_NEXTTX(i));
962 		EPIC_CDTXSYNC(sc, i, BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
963 	}
964 	sc->sc_txpending = 0;
965 	sc->sc_txdirty = 0;
966 	sc->sc_txlast = EPIC_NTXDESC - 1;
967 
968 	/*
969 	 * Initialize the receive descriptor ring.
970 	 */
971 	for (i = 0; i < EPIC_NRXDESC; i++) {
972 		ds = EPIC_DSRX(sc, i);
973 		if (ds->ds_mbuf == NULL) {
974 			if ((error = epic_add_rxbuf(sc, i)) != 0) {
975 				printf("%s: unable to allocate or map rx "
976 				    "buffer %d error = %d\n",
977 				    sc->sc_dev.dv_xname, i, error);
978 				/*
979 				 * XXX Should attempt to run with fewer receive
980 				 * XXX buffers instead of just failing.
981 				 */
982 				epic_rxdrain(sc);
983 				goto out;
984 			}
985 		}
986 	}
987 	sc->sc_rxptr = 0;
988 
989 	/*
990 	 * Initialize the interrupt mask and enable interrupts.
991 	 */
992 	bus_space_write_4(st, sh, EPIC_INTMASK, INTMASK);
993 	bus_space_write_4(st, sh, EPIC_GENCTL, genctl | GENCTL_INTENA);
994 
995 	/*
996 	 * Give the transmit and receive rings to the EPIC.
997 	 */
998 	bus_space_write_4(st, sh, EPIC_PTCDAR,
999 	    EPIC_CDTXADDR(sc, EPIC_NEXTTX(sc->sc_txlast)));
1000 	bus_space_write_4(st, sh, EPIC_PRCDAR,
1001 	    EPIC_CDRXADDR(sc, sc->sc_rxptr));
1002 
1003 	/*
1004 	 * Set the EPIC in motion.
1005 	 */
1006 	bus_space_write_4(st, sh, EPIC_COMMAND,
1007 	    COMMAND_RXQUEUED | COMMAND_START_RX);
1008 
1009 	/*
1010 	 * ...all done!
1011 	 */
1012 	ifp->if_flags |= IFF_RUNNING;
1013 	ifp->if_flags &= ~IFF_OACTIVE;
1014 
1015 	/*
1016 	 * Start the one second clock.
1017 	 */
1018 	callout_reset(&sc->sc_mii_callout, hz, epic_tick, sc);
1019 
1020 	/*
1021 	 * Attempt to start output on the interface.
1022 	 */
1023 	epic_start(ifp);
1024 
1025  out:
1026 	if (error)
1027 		printf("%s: interface not running\n", sc->sc_dev.dv_xname);
1028 	return (error);
1029 }
1030 
1031 /*
1032  * Drain the receive queue.
1033  */
1034 void
1035 epic_rxdrain(sc)
1036 	struct epic_softc *sc;
1037 {
1038 	struct epic_descsoft *ds;
1039 	int i;
1040 
1041 	for (i = 0; i < EPIC_NRXDESC; i++) {
1042 		ds = EPIC_DSRX(sc, i);
1043 		if (ds->ds_mbuf != NULL) {
1044 			bus_dmamap_unload(sc->sc_dmat, ds->ds_dmamap);
1045 			m_freem(ds->ds_mbuf);
1046 			ds->ds_mbuf = NULL;
1047 		}
1048 	}
1049 }
1050 
1051 /*
1052  * Stop transmission on the interface.
1053  */
1054 void
1055 epic_stop(ifp, disable)
1056 	struct ifnet *ifp;
1057 	int disable;
1058 {
1059 	struct epic_softc *sc = ifp->if_softc;
1060 	bus_space_tag_t st = sc->sc_st;
1061 	bus_space_handle_t sh = sc->sc_sh;
1062 	struct epic_descsoft *ds;
1063 	u_int32_t reg;
1064 	int i;
1065 
1066 	/*
1067 	 * Stop the one second clock.
1068 	 */
1069 	callout_stop(&sc->sc_mii_callout);
1070 
1071 	/* Down the MII. */
1072 	mii_down(&sc->sc_mii);
1073 
1074 	/* Paranoia... */
1075 	epic_fixup_clock_source(sc);
1076 
1077 	/*
1078 	 * Disable interrupts.
1079 	 */
1080 	reg = bus_space_read_4(st, sh, EPIC_GENCTL);
1081 	bus_space_write_4(st, sh, EPIC_GENCTL, reg & ~GENCTL_INTENA);
1082 	bus_space_write_4(st, sh, EPIC_INTMASK, 0);
1083 
1084 	/*
1085 	 * Stop the DMA engine and take the receiver off-line.
1086 	 */
1087 	bus_space_write_4(st, sh, EPIC_COMMAND, COMMAND_STOP_RDMA |
1088 	    COMMAND_STOP_TDMA | COMMAND_STOP_RX);
1089 
1090 	/*
1091 	 * Release any queued transmit buffers.
1092 	 */
1093 	for (i = 0; i < EPIC_NTXDESC; i++) {
1094 		ds = EPIC_DSTX(sc, i);
1095 		if (ds->ds_mbuf != NULL) {
1096 			bus_dmamap_unload(sc->sc_dmat, ds->ds_dmamap);
1097 			m_freem(ds->ds_mbuf);
1098 			ds->ds_mbuf = NULL;
1099 		}
1100 	}
1101 
1102 	if (disable)
1103 		epic_rxdrain(sc);
1104 
1105 	/*
1106 	 * Mark the interface down and cancel the watchdog timer.
1107 	 */
1108 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
1109 	ifp->if_timer = 0;
1110 }
1111 
1112 /*
1113  * Read the EPIC Serial EEPROM.
1114  */
1115 void
1116 epic_read_eeprom(sc, word, wordcnt, data)
1117 	struct epic_softc *sc;
1118 	int word, wordcnt;
1119 	u_int16_t *data;
1120 {
1121 	bus_space_tag_t st = sc->sc_st;
1122 	bus_space_handle_t sh = sc->sc_sh;
1123 	u_int16_t reg;
1124 	int i, x;
1125 
1126 #define	EEPROM_WAIT_READY(st, sh) \
1127 	while ((bus_space_read_4((st), (sh), EPIC_EECTL) & EECTL_EERDY) == 0) \
1128 		/* nothing */
1129 
1130 	/*
1131 	 * Enable the EEPROM.
1132 	 */
1133 	bus_space_write_4(st, sh, EPIC_EECTL, EECTL_ENABLE);
1134 	EEPROM_WAIT_READY(st, sh);
1135 
1136 	for (i = 0; i < wordcnt; i++) {
1137 		/* Send CHIP SELECT for one clock tick. */
1138 		bus_space_write_4(st, sh, EPIC_EECTL, EECTL_ENABLE|EECTL_EECS);
1139 		EEPROM_WAIT_READY(st, sh);
1140 
1141 		/* Shift in the READ opcode. */
1142 		for (x = 3; x > 0; x--) {
1143 			reg = EECTL_ENABLE|EECTL_EECS;
1144 			if (EPIC_EEPROM_OPC_READ & (1 << (x - 1)))
1145 				reg |= EECTL_EEDI;
1146 			bus_space_write_4(st, sh, EPIC_EECTL, reg);
1147 			EEPROM_WAIT_READY(st, sh);
1148 			bus_space_write_4(st, sh, EPIC_EECTL, reg|EECTL_EESK);
1149 			EEPROM_WAIT_READY(st, sh);
1150 			bus_space_write_4(st, sh, EPIC_EECTL, reg);
1151 			EEPROM_WAIT_READY(st, sh);
1152 		}
1153 
1154 		/* Shift in address. */
1155 		for (x = 6; x > 0; x--) {
1156 			reg = EECTL_ENABLE|EECTL_EECS;
1157 			if ((word + i) & (1 << (x - 1)))
1158 				reg |= EECTL_EEDI;
1159 			bus_space_write_4(st, sh, EPIC_EECTL, reg);
1160 			EEPROM_WAIT_READY(st, sh);
1161 			bus_space_write_4(st, sh, EPIC_EECTL, reg|EECTL_EESK);
1162 			EEPROM_WAIT_READY(st, sh);
1163 			bus_space_write_4(st, sh, EPIC_EECTL, reg);
1164 			EEPROM_WAIT_READY(st, sh);
1165 		}
1166 
1167 		/* Shift out data. */
1168 		reg = EECTL_ENABLE|EECTL_EECS;
1169 		data[i] = 0;
1170 		for (x = 16; x > 0; x--) {
1171 			bus_space_write_4(st, sh, EPIC_EECTL, reg|EECTL_EESK);
1172 			EEPROM_WAIT_READY(st, sh);
1173 			if (bus_space_read_4(st, sh, EPIC_EECTL) & EECTL_EEDO)
1174 				data[i] |= (1 << (x - 1));
1175 			bus_space_write_4(st, sh, EPIC_EECTL, reg);
1176 			EEPROM_WAIT_READY(st, sh);
1177 		}
1178 
1179 		/* Clear CHIP SELECT. */
1180 		bus_space_write_4(st, sh, EPIC_EECTL, EECTL_ENABLE);
1181 		EEPROM_WAIT_READY(st, sh);
1182 	}
1183 
1184 	/*
1185 	 * Disable the EEPROM.
1186 	 */
1187 	bus_space_write_4(st, sh, EPIC_EECTL, 0);
1188 
1189 #undef EEPROM_WAIT_READY
1190 }
1191 
1192 /*
1193  * Add a receive buffer to the indicated descriptor.
1194  */
1195 int
1196 epic_add_rxbuf(sc, idx)
1197 	struct epic_softc *sc;
1198 	int idx;
1199 {
1200 	struct epic_descsoft *ds = EPIC_DSRX(sc, idx);
1201 	struct mbuf *m;
1202 	int error;
1203 
1204 	MGETHDR(m, M_DONTWAIT, MT_DATA);
1205 	if (m == NULL)
1206 		return (ENOBUFS);
1207 
1208 	MCLGET(m, M_DONTWAIT);
1209 	if ((m->m_flags & M_EXT) == 0) {
1210 		m_freem(m);
1211 		return (ENOBUFS);
1212 	}
1213 
1214 	if (ds->ds_mbuf != NULL)
1215 		bus_dmamap_unload(sc->sc_dmat, ds->ds_dmamap);
1216 
1217 	ds->ds_mbuf = m;
1218 
1219 	error = bus_dmamap_load(sc->sc_dmat, ds->ds_dmamap,
1220 	    m->m_ext.ext_buf, m->m_ext.ext_size, NULL, BUS_DMA_NOWAIT);
1221 	if (error) {
1222 		printf("%s: can't load rx DMA map %d, error = %d\n",
1223 		    sc->sc_dev.dv_xname, idx, error);
1224 		panic("epic_add_rxbuf");	/* XXX */
1225 	}
1226 
1227 	bus_dmamap_sync(sc->sc_dmat, ds->ds_dmamap, 0,
1228 	    ds->ds_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
1229 
1230 	EPIC_INIT_RXDESC(sc, idx);
1231 
1232 	return (0);
1233 }
1234 
1235 /*
1236  * Set the EPIC multicast hash table.
1237  *
1238  * NOTE: We rely on a recently-updated mii_media_active here!
1239  */
1240 void
1241 epic_set_mchash(sc)
1242 	struct epic_softc *sc;
1243 {
1244 	struct ethercom *ec = &sc->sc_ethercom;
1245 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1246 	struct ether_multi *enm;
1247 	struct ether_multistep step;
1248 	u_int32_t hash, mchash[4];
1249 
1250 	/*
1251 	 * Set up the multicast address filter by passing all multicast
1252 	 * addresses through a CRC generator, and then using the low-order
1253 	 * 6 bits as an index into the 64 bit multicast hash table (only
1254 	 * the lower 16 bits of each 32 bit multicast hash register are
1255 	 * valid).  The high order bits select the register, while the
1256 	 * rest of the bits select the bit within the register.
1257 	 */
1258 
1259 	if (ifp->if_flags & IFF_PROMISC)
1260 		goto allmulti;
1261 
1262 	if (IFM_SUBTYPE(sc->sc_mii.mii_media_active) == IFM_10_T) {
1263 		/* XXX hardware bug in 10Mbps mode. */
1264 		goto allmulti;
1265 	}
1266 
1267 	mchash[0] = mchash[1] = mchash[2] = mchash[3] = 0;
1268 
1269 	ETHER_FIRST_MULTI(step, ec, enm);
1270 	while (enm != NULL) {
1271 		if (bcmp(enm->enm_addrlo, enm->enm_addrhi, ETHER_ADDR_LEN)) {
1272 			/*
1273 			 * We must listen to a range of multicast addresses.
1274 			 * For now, just accept all multicasts, rather than
1275 			 * trying to set only those filter bits needed to match
1276 			 * the range.  (At this time, the only use of address
1277 			 * ranges is for IP multicast routing, for which the
1278 			 * range is big enough to require all bits set.)
1279 			 */
1280 			goto allmulti;
1281 		}
1282 
1283 		hash = ether_crc32_be(enm->enm_addrlo, ETHER_ADDR_LEN);
1284 		hash >>= 26;
1285 
1286 		/* Set the corresponding bit in the hash table. */
1287 		mchash[hash >> 4] |= 1 << (hash & 0xf);
1288 
1289 		ETHER_NEXT_MULTI(step, enm);
1290 	}
1291 
1292 	ifp->if_flags &= ~IFF_ALLMULTI;
1293 	goto sethash;
1294 
1295  allmulti:
1296 	ifp->if_flags |= IFF_ALLMULTI;
1297 	mchash[0] = mchash[1] = mchash[2] = mchash[3] = 0xffff;
1298 
1299  sethash:
1300 	bus_space_write_4(sc->sc_st, sc->sc_sh, EPIC_MC0, mchash[0]);
1301 	bus_space_write_4(sc->sc_st, sc->sc_sh, EPIC_MC1, mchash[1]);
1302 	bus_space_write_4(sc->sc_st, sc->sc_sh, EPIC_MC2, mchash[2]);
1303 	bus_space_write_4(sc->sc_st, sc->sc_sh, EPIC_MC3, mchash[3]);
1304 }
1305 
1306 /*
1307  * Wait for the MII to become ready.
1308  */
1309 int
1310 epic_mii_wait(sc, rw)
1311 	struct epic_softc *sc;
1312 	u_int32_t rw;
1313 {
1314 	int i;
1315 
1316 	for (i = 0; i < 50; i++) {
1317 		if ((bus_space_read_4(sc->sc_st, sc->sc_sh, EPIC_MMCTL) & rw)
1318 		    == 0)
1319 			break;
1320 		delay(2);
1321 	}
1322 	if (i == 50) {
1323 		printf("%s: MII timed out\n", sc->sc_dev.dv_xname);
1324 		return (1);
1325 	}
1326 
1327 	return (0);
1328 }
1329 
1330 /*
1331  * Read from the MII.
1332  */
1333 int
1334 epic_mii_read(self, phy, reg)
1335 	struct device *self;
1336 	int phy, reg;
1337 {
1338 	struct epic_softc *sc = (struct epic_softc *)self;
1339 
1340 	if (epic_mii_wait(sc, MMCTL_WRITE))
1341 		return (0);
1342 
1343 	bus_space_write_4(sc->sc_st, sc->sc_sh, EPIC_MMCTL,
1344 	    MMCTL_ARG(phy, reg, MMCTL_READ));
1345 
1346 	if (epic_mii_wait(sc, MMCTL_READ))
1347 		return (0);
1348 
1349 	return (bus_space_read_4(sc->sc_st, sc->sc_sh, EPIC_MMDATA) &
1350 	    MMDATA_MASK);
1351 }
1352 
1353 /*
1354  * Write to the MII.
1355  */
1356 void
1357 epic_mii_write(self, phy, reg, val)
1358 	struct device *self;
1359 	int phy, reg, val;
1360 {
1361 	struct epic_softc *sc = (struct epic_softc *)self;
1362 
1363 	if (epic_mii_wait(sc, MMCTL_WRITE))
1364 		return;
1365 
1366 	bus_space_write_4(sc->sc_st, sc->sc_sh, EPIC_MMDATA, val);
1367 	bus_space_write_4(sc->sc_st, sc->sc_sh, EPIC_MMCTL,
1368 	    MMCTL_ARG(phy, reg, MMCTL_WRITE));
1369 }
1370 
1371 /*
1372  * Callback from PHY when media changes.
1373  */
1374 void
1375 epic_statchg(self)
1376 	struct device *self;
1377 {
1378 	struct epic_softc *sc = (struct epic_softc *)self;
1379 	u_int32_t txcon;
1380 
1381 	/*
1382 	 * Update loopback bits in TXCON to reflect duplex mode.
1383 	 */
1384 	txcon = bus_space_read_4(sc->sc_st, sc->sc_sh, EPIC_TXCON);
1385 	if (sc->sc_mii.mii_media_active & IFM_FDX)
1386 		txcon |= (TXCON_LOOPBACK_D1|TXCON_LOOPBACK_D2);
1387 	else
1388 		txcon &= ~(TXCON_LOOPBACK_D1|TXCON_LOOPBACK_D2);
1389 	bus_space_write_4(sc->sc_st, sc->sc_sh, EPIC_TXCON, txcon);
1390 
1391 	/*
1392 	 * There is a multicast filter bug in 10Mbps mode.  Kick the
1393 	 * multicast filter in case the speed changed.
1394 	 */
1395 	epic_set_mchash(sc);
1396 }
1397 
1398 /*
1399  * Callback from ifmedia to request current media status.
1400  */
1401 void
1402 epic_mediastatus(ifp, ifmr)
1403 	struct ifnet *ifp;
1404 	struct ifmediareq *ifmr;
1405 {
1406 	struct epic_softc *sc = ifp->if_softc;
1407 
1408 	mii_pollstat(&sc->sc_mii);
1409 	ifmr->ifm_status = sc->sc_mii.mii_media_status;
1410 	ifmr->ifm_active = sc->sc_mii.mii_media_active;
1411 }
1412 
1413 /*
1414  * Callback from ifmedia to request new media setting.
1415  */
1416 int
1417 epic_mediachange(ifp)
1418 	struct ifnet *ifp;
1419 {
1420 	struct epic_softc *sc = ifp->if_softc;
1421 
1422 	if (ifp->if_flags & IFF_UP)
1423 		mii_mediachg(&sc->sc_mii);
1424 	return (0);
1425 }
1426