xref: /openbsd-src/sys/dev/ic/gem.c (revision 91f110e064cd7c194e59e019b83bb7496c1c84d4)
1 /*	$OpenBSD: gem.c,v 1.102 2014/03/14 11:04:24 dlg Exp $	*/
2 /*	$NetBSD: gem.c,v 1.1 2001/09/16 00:11:43 eeh Exp $ */
3 
4 /*
5  *
6  * Copyright (C) 2001 Eduardo Horvath.
7  * All rights reserved.
8  *
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR  ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR  BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  */
32 
33 /*
34  * Driver for Sun GEM ethernet controllers.
35  */
36 
37 #include "bpfilter.h"
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/timeout.h>
42 #include <sys/mbuf.h>
43 #include <sys/syslog.h>
44 #include <sys/malloc.h>
45 #include <sys/kernel.h>
46 #include <sys/socket.h>
47 #include <sys/ioctl.h>
48 #include <sys/errno.h>
49 #include <sys/device.h>
50 
51 #include <machine/endian.h>
52 
53 #include <net/if.h>
54 #include <net/if_dl.h>
55 #include <net/if_media.h>
56 
57 #ifdef INET
58 #include <netinet/in.h>
59 #include <netinet/in_systm.h>
60 #include <netinet/ip.h>
61 #include <netinet/if_ether.h>
62 #include <netinet/tcp.h>
63 #include <netinet/udp.h>
64 #endif
65 
66 #if NBPFILTER > 0
67 #include <net/bpf.h>
68 #endif
69 
70 #include <machine/bus.h>
71 #include <machine/intr.h>
72 
73 #include <dev/mii/mii.h>
74 #include <dev/mii/miivar.h>
75 #include <dev/mii/mii_bitbang.h>
76 
77 #include <dev/ic/gemreg.h>
78 #include <dev/ic/gemvar.h>
79 
80 #define TRIES	10000
81 
82 struct cfdriver gem_cd = {
83 	NULL, "gem", DV_IFNET
84 };
85 
86 void		gem_start(struct ifnet *);
87 void		gem_stop(struct ifnet *, int);
88 int		gem_ioctl(struct ifnet *, u_long, caddr_t);
89 void		gem_tick(void *);
90 void		gem_watchdog(struct ifnet *);
91 int		gem_init(struct ifnet *);
92 void		gem_init_regs(struct gem_softc *);
93 int		gem_ringsize(int);
94 int		gem_meminit(struct gem_softc *);
95 void		gem_mifinit(struct gem_softc *);
96 int		gem_bitwait(struct gem_softc *, bus_space_handle_t, int,
97 		    u_int32_t, u_int32_t);
98 void		gem_reset(struct gem_softc *);
99 int		gem_reset_rx(struct gem_softc *);
100 int		gem_reset_tx(struct gem_softc *);
101 int		gem_disable_rx(struct gem_softc *);
102 int		gem_disable_tx(struct gem_softc *);
103 void		gem_rx_watchdog(void *);
104 void		gem_rxdrain(struct gem_softc *);
105 void		gem_fill_rx_ring(struct gem_softc *);
106 int		gem_add_rxbuf(struct gem_softc *, int idx);
107 void		gem_iff(struct gem_softc *);
108 
109 /* MII methods & callbacks */
110 int		gem_mii_readreg(struct device *, int, int);
111 void		gem_mii_writereg(struct device *, int, int, int);
112 void		gem_mii_statchg(struct device *);
113 int		gem_pcs_readreg(struct device *, int, int);
114 void		gem_pcs_writereg(struct device *, int, int, int);
115 
116 int		gem_mediachange(struct ifnet *);
117 void		gem_mediastatus(struct ifnet *, struct ifmediareq *);
118 
119 int		gem_eint(struct gem_softc *, u_int);
120 int		gem_rint(struct gem_softc *);
121 int		gem_tint(struct gem_softc *, u_int32_t);
122 int		gem_pint(struct gem_softc *);
123 void		gem_rxcksum(struct mbuf *, u_int64_t);
124 
125 #ifdef GEM_DEBUG
126 #define	DPRINTF(sc, x)	if ((sc)->sc_arpcom.ac_if.if_flags & IFF_DEBUG) \
127 				printf x
128 #else
129 #define	DPRINTF(sc, x)	/* nothing */
130 #endif
131 
132 /*
133  * Attach a Gem interface to the system.
134  */
135 void
136 gem_config(struct gem_softc *sc)
137 {
138 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
139 	struct mii_data *mii = &sc->sc_mii;
140 	struct mii_softc *child;
141 	int i, error, mii_flags, phyad;
142 	struct ifmedia_entry *ifm;
143 
144 	/* Make sure the chip is stopped. */
145 	ifp->if_softc = sc;
146 	gem_reset(sc);
147 
148 	/*
149 	 * Allocate the control data structures, and create and load the
150 	 * DMA map for it.
151 	 */
152 	if ((error = bus_dmamem_alloc(sc->sc_dmatag,
153 	    sizeof(struct gem_control_data), PAGE_SIZE, 0, &sc->sc_cdseg,
154 	    1, &sc->sc_cdnseg, 0)) != 0) {
155 		printf("\n%s: unable to allocate control data, error = %d\n",
156 		    sc->sc_dev.dv_xname, error);
157 		goto fail_0;
158 	}
159 
160 	/* XXX should map this in with correct endianness */
161 	if ((error = bus_dmamem_map(sc->sc_dmatag, &sc->sc_cdseg, sc->sc_cdnseg,
162 	    sizeof(struct gem_control_data), (caddr_t *)&sc->sc_control_data,
163 	    BUS_DMA_COHERENT)) != 0) {
164 		printf("\n%s: unable to map control data, error = %d\n",
165 		    sc->sc_dev.dv_xname, error);
166 		goto fail_1;
167 	}
168 
169 	if ((error = bus_dmamap_create(sc->sc_dmatag,
170 	    sizeof(struct gem_control_data), 1,
171 	    sizeof(struct gem_control_data), 0, 0, &sc->sc_cddmamap)) != 0) {
172 		printf("\n%s: unable to create control data DMA map, "
173 		    "error = %d\n", sc->sc_dev.dv_xname, error);
174 		goto fail_2;
175 	}
176 
177 	if ((error = bus_dmamap_load(sc->sc_dmatag, sc->sc_cddmamap,
178 	    sc->sc_control_data, sizeof(struct gem_control_data), NULL,
179 	    0)) != 0) {
180 		printf("\n%s: unable to load control data DMA map, error = %d\n",
181 		    sc->sc_dev.dv_xname, error);
182 		goto fail_3;
183 	}
184 
185 	/*
186 	 * Create the receive buffer DMA maps.
187 	 */
188 	for (i = 0; i < GEM_NRXDESC; i++) {
189 		if ((error = bus_dmamap_create(sc->sc_dmatag, MCLBYTES, 1,
190 		    MCLBYTES, 0, 0, &sc->sc_rxsoft[i].rxs_dmamap)) != 0) {
191 			printf("\n%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 		sc->sc_rxsoft[i].rxs_mbuf = NULL;
196 	}
197 	/*
198 	 * Create the transmit buffer DMA maps.
199 	 */
200 	for (i = 0; i < GEM_NTXDESC; i++) {
201 		if ((error = bus_dmamap_create(sc->sc_dmatag, MCLBYTES,
202 		    GEM_NTXSEGS, MCLBYTES, 0, BUS_DMA_NOWAIT,
203 		    &sc->sc_txd[i].sd_map)) != 0) {
204 			printf("\n%s: unable to create tx DMA map %d, "
205 			    "error = %d\n", sc->sc_dev.dv_xname, i, error);
206 			goto fail_6;
207 		}
208 		sc->sc_txd[i].sd_mbuf = NULL;
209 	}
210 
211 	/*
212 	 * From this point forward, the attachment cannot fail.  A failure
213 	 * before this point releases all resources that may have been
214 	 * allocated.
215 	 */
216 
217 	/* Announce ourselves. */
218 	printf(", address %s\n", ether_sprintf(sc->sc_arpcom.ac_enaddr));
219 
220 	/* Get RX FIFO size */
221 	sc->sc_rxfifosize = 64 *
222 	    bus_space_read_4(sc->sc_bustag, sc->sc_h1, GEM_RX_FIFO_SIZE);
223 
224 	/* Initialize ifnet structure. */
225 	strlcpy(ifp->if_xname, sc->sc_dev.dv_xname, sizeof ifp->if_xname);
226 	ifp->if_softc = sc;
227 	ifp->if_flags =
228 	    IFF_BROADCAST | IFF_SIMPLEX | IFF_NOTRAILERS | IFF_MULTICAST;
229 	ifp->if_start = gem_start;
230 	ifp->if_ioctl = gem_ioctl;
231 	ifp->if_watchdog = gem_watchdog;
232 	IFQ_SET_MAXLEN(&ifp->if_snd, GEM_NTXDESC - 1);
233 	IFQ_SET_READY(&ifp->if_snd);
234 
235 	/* Hardware reads RX descriptors in multiples of four. */
236 	m_clsetwms(ifp, MCLBYTES, 4, GEM_NRXDESC - 4);
237 
238 	ifp->if_capabilities = IFCAP_VLAN_MTU;
239 
240 	/* Initialize ifmedia structures and MII info */
241 	mii->mii_ifp = ifp;
242 	mii->mii_readreg = gem_mii_readreg;
243 	mii->mii_writereg = gem_mii_writereg;
244 	mii->mii_statchg = gem_mii_statchg;
245 
246 	ifmedia_init(&mii->mii_media, 0, gem_mediachange, gem_mediastatus);
247 
248 	/* Bad things will happen if we touch this register on ERI. */
249 	if (sc->sc_variant != GEM_SUN_ERI)
250 		bus_space_write_4(sc->sc_bustag, sc->sc_h1,
251 		    GEM_MII_DATAPATH_MODE, 0);
252 
253 	gem_mifinit(sc);
254 
255 	mii_flags = MIIF_DOPAUSE;
256 
257 	/*
258 	 * Look for an external PHY.
259 	 */
260 	if (sc->sc_mif_config & GEM_MIF_CONFIG_MDI1) {
261 		sc->sc_mif_config |= GEM_MIF_CONFIG_PHY_SEL;
262 		bus_space_write_4(sc->sc_bustag, sc->sc_h1,
263 	            GEM_MIF_CONFIG, sc->sc_mif_config);
264 
265 		switch (sc->sc_variant) {
266 		case GEM_SUN_ERI:
267 			phyad = GEM_PHYAD_EXTERNAL;
268 			break;
269 		default:
270 			phyad = MII_PHY_ANY;
271 			break;
272 		}
273 
274 		mii_attach(&sc->sc_dev, mii, 0xffffffff, phyad,
275 		    MII_OFFSET_ANY, mii_flags);
276 	}
277 
278 	/*
279 	 * Fall back on an internal PHY if no external PHY was found.
280 	 * Note that with Apple (K2) GMACs GEM_MIF_CONFIG_MDI0 can't be
281 	 * trusted when the firmware has powered down the chip
282 	 */
283 	child = LIST_FIRST(&mii->mii_phys);
284 	if (child == NULL &&
285 	    (sc->sc_mif_config & GEM_MIF_CONFIG_MDI0 || GEM_IS_APPLE(sc))) {
286 		sc->sc_mif_config &= ~GEM_MIF_CONFIG_PHY_SEL;
287 		bus_space_write_4(sc->sc_bustag, sc->sc_h1,
288 	            GEM_MIF_CONFIG, sc->sc_mif_config);
289 
290 		switch (sc->sc_variant) {
291 		case GEM_SUN_ERI:
292 		case GEM_APPLE_K2_GMAC:
293 			phyad = GEM_PHYAD_INTERNAL;
294 			break;
295 		case GEM_APPLE_GMAC:
296 			phyad = GEM_PHYAD_EXTERNAL;
297 			break;
298 		default:
299 			phyad = MII_PHY_ANY;
300 			break;
301 		}
302 
303 		mii_attach(&sc->sc_dev, mii, 0xffffffff, phyad,
304 		    MII_OFFSET_ANY, mii_flags);
305 	}
306 
307 	/*
308 	 * Try the external PCS SERDES if we didn't find any MII
309 	 * devices.
310 	 */
311 	child = LIST_FIRST(&mii->mii_phys);
312 	if (child == NULL && sc->sc_variant != GEM_SUN_ERI) {
313 		bus_space_write_4(sc->sc_bustag, sc->sc_h1,
314 		    GEM_MII_DATAPATH_MODE, GEM_MII_DATAPATH_SERDES);
315 
316 		bus_space_write_4(sc->sc_bustag, sc->sc_h1,
317 		    GEM_MII_SLINK_CONTROL,
318 		    GEM_MII_SLINK_LOOPBACK|GEM_MII_SLINK_EN_SYNC_D);
319 
320 		bus_space_write_4(sc->sc_bustag, sc->sc_h1,
321 		     GEM_MII_CONFIG, GEM_MII_CONFIG_ENABLE);
322 
323 		mii->mii_readreg = gem_pcs_readreg;
324 		mii->mii_writereg = gem_pcs_writereg;
325 
326 		mii_flags |= MIIF_NOISOLATE;
327 
328 		mii_attach(&sc->sc_dev, mii, 0xffffffff, MII_PHY_ANY,
329 		    MII_OFFSET_ANY, mii_flags);
330 	}
331 
332 	child = LIST_FIRST(&mii->mii_phys);
333 	if (child == NULL) {
334 		/* No PHY attached */
335 		ifmedia_add(&sc->sc_media, IFM_ETHER|IFM_MANUAL, 0, NULL);
336 		ifmedia_set(&sc->sc_media, IFM_ETHER|IFM_MANUAL);
337 	} else {
338 		/*
339 		 * XXX - we can really do the following ONLY if the
340 		 * phy indeed has the auto negotiation capability!!
341 		 */
342 		ifmedia_set(&sc->sc_media, IFM_ETHER|IFM_AUTO);
343 	}
344 
345 	/* Check if we support GigE media. */
346 	TAILQ_FOREACH(ifm, &sc->sc_media.ifm_list, ifm_list) {
347 		if (IFM_SUBTYPE(ifm->ifm_media) == IFM_1000_T ||
348 		    IFM_SUBTYPE(ifm->ifm_media) == IFM_1000_SX ||
349 		    IFM_SUBTYPE(ifm->ifm_media) == IFM_1000_LX ||
350 		    IFM_SUBTYPE(ifm->ifm_media) == IFM_1000_CX) {
351 			sc->sc_flags |= GEM_GIGABIT;
352 			break;
353 		}
354 	}
355 
356 	/* Attach the interface. */
357 	if_attach(ifp);
358 	ether_ifattach(ifp);
359 
360 	timeout_set(&sc->sc_tick_ch, gem_tick, sc);
361 	timeout_set(&sc->sc_rx_watchdog, gem_rx_watchdog, sc);
362 	return;
363 
364 	/*
365 	 * Free any resources we've allocated during the failed attach
366 	 * attempt.  Do this in reverse order and fall through.
367 	 */
368  fail_6:
369 	for (i = 0; i < GEM_NTXDESC; i++) {
370 		if (sc->sc_txd[i].sd_map != NULL)
371 			bus_dmamap_destroy(sc->sc_dmatag,
372 			    sc->sc_txd[i].sd_map);
373 	}
374  fail_5:
375 	for (i = 0; i < GEM_NRXDESC; i++) {
376 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
377 			bus_dmamap_destroy(sc->sc_dmatag,
378 			    sc->sc_rxsoft[i].rxs_dmamap);
379 	}
380 	bus_dmamap_unload(sc->sc_dmatag, sc->sc_cddmamap);
381  fail_3:
382 	bus_dmamap_destroy(sc->sc_dmatag, sc->sc_cddmamap);
383  fail_2:
384 	bus_dmamem_unmap(sc->sc_dmatag, (caddr_t)sc->sc_control_data,
385 	    sizeof(struct gem_control_data));
386  fail_1:
387 	bus_dmamem_free(sc->sc_dmatag, &sc->sc_cdseg, sc->sc_cdnseg);
388  fail_0:
389 	return;
390 }
391 
392 void
393 gem_unconfig(struct gem_softc *sc)
394 {
395 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
396 	int i;
397 
398 	gem_stop(ifp, 1);
399 
400 	for (i = 0; i < GEM_NTXDESC; i++) {
401 		if (sc->sc_txd[i].sd_map != NULL)
402 			bus_dmamap_destroy(sc->sc_dmatag,
403 			    sc->sc_txd[i].sd_map);
404 	}
405 	for (i = 0; i < GEM_NRXDESC; i++) {
406 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
407 			bus_dmamap_destroy(sc->sc_dmatag,
408 			    sc->sc_rxsoft[i].rxs_dmamap);
409 	}
410 	bus_dmamap_unload(sc->sc_dmatag, sc->sc_cddmamap);
411 	bus_dmamap_destroy(sc->sc_dmatag, sc->sc_cddmamap);
412 	bus_dmamem_unmap(sc->sc_dmatag, (caddr_t)sc->sc_control_data,
413 	    sizeof(struct gem_control_data));
414 	bus_dmamem_free(sc->sc_dmatag, &sc->sc_cdseg, sc->sc_cdnseg);
415 
416 	/* Detach all PHYs */
417 	mii_detach(&sc->sc_mii, MII_PHY_ANY, MII_OFFSET_ANY);
418 
419 	/* Delete all remaining media. */
420 	ifmedia_delete_instance(&sc->sc_mii.mii_media, IFM_INST_ANY);
421 
422 	ether_ifdetach(ifp);
423 	if_detach(ifp);
424 }
425 
426 
427 void
428 gem_tick(void *arg)
429 {
430 	struct gem_softc *sc = arg;
431 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
432 	bus_space_tag_t t = sc->sc_bustag;
433 	bus_space_handle_t mac = sc->sc_h1;
434 	int s;
435 	u_int32_t v;
436 
437 	/* unload collisions counters */
438 	v = bus_space_read_4(t, mac, GEM_MAC_EXCESS_COLL_CNT) +
439 	    bus_space_read_4(t, mac, GEM_MAC_LATE_COLL_CNT);
440 	ifp->if_collisions += v +
441 	    bus_space_read_4(t, mac, GEM_MAC_NORM_COLL_CNT) +
442 	    bus_space_read_4(t, mac, GEM_MAC_FIRST_COLL_CNT);
443 	ifp->if_oerrors += v;
444 
445 	/* read error counters */
446 	ifp->if_ierrors +=
447 	    bus_space_read_4(t, mac, GEM_MAC_RX_LEN_ERR_CNT) +
448 	    bus_space_read_4(t, mac, GEM_MAC_RX_ALIGN_ERR) +
449 	    bus_space_read_4(t, mac, GEM_MAC_RX_CRC_ERR_CNT) +
450 	    bus_space_read_4(t, mac, GEM_MAC_RX_CODE_VIOL);
451 
452 	/* clear the hardware counters */
453 	bus_space_write_4(t, mac, GEM_MAC_NORM_COLL_CNT, 0);
454 	bus_space_write_4(t, mac, GEM_MAC_FIRST_COLL_CNT, 0);
455 	bus_space_write_4(t, mac, GEM_MAC_EXCESS_COLL_CNT, 0);
456 	bus_space_write_4(t, mac, GEM_MAC_LATE_COLL_CNT, 0);
457 	bus_space_write_4(t, mac, GEM_MAC_RX_LEN_ERR_CNT, 0);
458 	bus_space_write_4(t, mac, GEM_MAC_RX_ALIGN_ERR, 0);
459 	bus_space_write_4(t, mac, GEM_MAC_RX_CRC_ERR_CNT, 0);
460 	bus_space_write_4(t, mac, GEM_MAC_RX_CODE_VIOL, 0);
461 
462 	s = splnet();
463 	mii_tick(&sc->sc_mii);
464 	splx(s);
465 
466 	timeout_add_sec(&sc->sc_tick_ch, 1);
467 }
468 
469 int
470 gem_bitwait(struct gem_softc *sc, bus_space_handle_t h, int r,
471    u_int32_t clr, u_int32_t set)
472 {
473 	int i;
474 	u_int32_t reg;
475 
476 	for (i = TRIES; i--; DELAY(100)) {
477 		reg = bus_space_read_4(sc->sc_bustag, h, r);
478 		if ((reg & clr) == 0 && (reg & set) == set)
479 			return (1);
480 	}
481 
482 	return (0);
483 }
484 
485 void
486 gem_reset(struct gem_softc *sc)
487 {
488 	bus_space_tag_t t = sc->sc_bustag;
489 	bus_space_handle_t h = sc->sc_h2;
490 	int s;
491 
492 	s = splnet();
493 	DPRINTF(sc, ("%s: gem_reset\n", sc->sc_dev.dv_xname));
494 	gem_reset_rx(sc);
495 	gem_reset_tx(sc);
496 
497 	/* Do a full reset */
498 	bus_space_write_4(t, h, GEM_RESET, GEM_RESET_RX|GEM_RESET_TX);
499 	if (!gem_bitwait(sc, h, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX, 0))
500 		printf("%s: cannot reset device\n", sc->sc_dev.dv_xname);
501 	splx(s);
502 }
503 
504 
505 /*
506  * Drain the receive queue.
507  */
508 void
509 gem_rxdrain(struct gem_softc *sc)
510 {
511 	struct gem_rxsoft *rxs;
512 	int i;
513 
514 	for (i = 0; i < GEM_NRXDESC; i++) {
515 		rxs = &sc->sc_rxsoft[i];
516 		if (rxs->rxs_mbuf != NULL) {
517 			bus_dmamap_sync(sc->sc_dmatag, rxs->rxs_dmamap, 0,
518 			    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);
519 			bus_dmamap_unload(sc->sc_dmatag, rxs->rxs_dmamap);
520 			m_freem(rxs->rxs_mbuf);
521 			rxs->rxs_mbuf = NULL;
522 		}
523 	}
524 	sc->sc_rx_prod = sc->sc_rx_cons = sc->sc_rx_cnt = 0;
525 }
526 
527 /*
528  * Reset the whole thing.
529  */
530 void
531 gem_stop(struct ifnet *ifp, int softonly)
532 {
533 	struct gem_softc *sc = (struct gem_softc *)ifp->if_softc;
534 	struct gem_sxd *sd;
535 	u_int32_t i;
536 
537 	DPRINTF(sc, ("%s: gem_stop\n", sc->sc_dev.dv_xname));
538 
539 	timeout_del(&sc->sc_tick_ch);
540 
541 	/*
542 	 * Mark the interface down and cancel the watchdog timer.
543 	 */
544 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
545 	ifp->if_timer = 0;
546 
547 	if (!softonly) {
548 		mii_down(&sc->sc_mii);
549 
550 		gem_reset_rx(sc);
551 		gem_reset_tx(sc);
552 	}
553 
554 	/*
555 	 * Release any queued transmit buffers.
556 	 */
557 	for (i = 0; i < GEM_NTXDESC; i++) {
558 		sd = &sc->sc_txd[i];
559 		if (sd->sd_mbuf != NULL) {
560 			bus_dmamap_sync(sc->sc_dmatag, sd->sd_map, 0,
561 			    sd->sd_map->dm_mapsize, BUS_DMASYNC_POSTWRITE);
562 			bus_dmamap_unload(sc->sc_dmatag, sd->sd_map);
563 			m_freem(sd->sd_mbuf);
564 			sd->sd_mbuf = NULL;
565 		}
566 	}
567 	sc->sc_tx_cnt = sc->sc_tx_prod = sc->sc_tx_cons = 0;
568 
569 	gem_rxdrain(sc);
570 }
571 
572 
573 /*
574  * Reset the receiver
575  */
576 int
577 gem_reset_rx(struct gem_softc *sc)
578 {
579 	bus_space_tag_t t = sc->sc_bustag;
580 	bus_space_handle_t h = sc->sc_h1, h2 = sc->sc_h2;
581 
582 	/*
583 	 * Resetting while DMA is in progress can cause a bus hang, so we
584 	 * disable DMA first.
585 	 */
586 	gem_disable_rx(sc);
587 	bus_space_write_4(t, h, GEM_RX_CONFIG, 0);
588 	/* Wait till it finishes */
589 	if (!gem_bitwait(sc, h, GEM_RX_CONFIG, 1, 0))
590 		printf("%s: cannot disable rx dma\n", sc->sc_dev.dv_xname);
591 	/* Wait 5ms extra. */
592 	delay(5000);
593 
594 	/* Finally, reset the ERX */
595 	bus_space_write_4(t, h2, GEM_RESET, GEM_RESET_RX);
596 	/* Wait till it finishes */
597 	if (!gem_bitwait(sc, h2, GEM_RESET, GEM_RESET_RX, 0)) {
598 		printf("%s: cannot reset receiver\n", sc->sc_dev.dv_xname);
599 		return (1);
600 	}
601 	return (0);
602 }
603 
604 
605 /*
606  * Reset the transmitter
607  */
608 int
609 gem_reset_tx(struct gem_softc *sc)
610 {
611 	bus_space_tag_t t = sc->sc_bustag;
612 	bus_space_handle_t h = sc->sc_h1, h2 = sc->sc_h2;
613 
614 	/*
615 	 * Resetting while DMA is in progress can cause a bus hang, so we
616 	 * disable DMA first.
617 	 */
618 	gem_disable_tx(sc);
619 	bus_space_write_4(t, h, GEM_TX_CONFIG, 0);
620 	/* Wait till it finishes */
621 	if (!gem_bitwait(sc, h, GEM_TX_CONFIG, 1, 0))
622 		printf("%s: cannot disable tx dma\n", sc->sc_dev.dv_xname);
623 	/* Wait 5ms extra. */
624 	delay(5000);
625 
626 	/* Finally, reset the ETX */
627 	bus_space_write_4(t, h2, GEM_RESET, GEM_RESET_TX);
628 	/* Wait till it finishes */
629 	if (!gem_bitwait(sc, h2, GEM_RESET, GEM_RESET_TX, 0)) {
630 		printf("%s: cannot reset transmitter\n",
631 			sc->sc_dev.dv_xname);
632 		return (1);
633 	}
634 	return (0);
635 }
636 
637 /*
638  * Disable receiver.
639  */
640 int
641 gem_disable_rx(struct gem_softc *sc)
642 {
643 	bus_space_tag_t t = sc->sc_bustag;
644 	bus_space_handle_t h = sc->sc_h1;
645 	u_int32_t cfg;
646 
647 	/* Flip the enable bit */
648 	cfg = bus_space_read_4(t, h, GEM_MAC_RX_CONFIG);
649 	cfg &= ~GEM_MAC_RX_ENABLE;
650 	bus_space_write_4(t, h, GEM_MAC_RX_CONFIG, cfg);
651 
652 	/* Wait for it to finish */
653 	return (gem_bitwait(sc, h, GEM_MAC_RX_CONFIG, GEM_MAC_RX_ENABLE, 0));
654 }
655 
656 /*
657  * Disable transmitter.
658  */
659 int
660 gem_disable_tx(struct gem_softc *sc)
661 {
662 	bus_space_tag_t t = sc->sc_bustag;
663 	bus_space_handle_t h = sc->sc_h1;
664 	u_int32_t cfg;
665 
666 	/* Flip the enable bit */
667 	cfg = bus_space_read_4(t, h, GEM_MAC_TX_CONFIG);
668 	cfg &= ~GEM_MAC_TX_ENABLE;
669 	bus_space_write_4(t, h, GEM_MAC_TX_CONFIG, cfg);
670 
671 	/* Wait for it to finish */
672 	return (gem_bitwait(sc, h, GEM_MAC_TX_CONFIG, GEM_MAC_TX_ENABLE, 0));
673 }
674 
675 /*
676  * Initialize interface.
677  */
678 int
679 gem_meminit(struct gem_softc *sc)
680 {
681 	int i;
682 
683 	/*
684 	 * Initialize the transmit descriptor ring.
685 	 */
686 	for (i = 0; i < GEM_NTXDESC; i++) {
687 		sc->sc_txdescs[i].gd_flags = 0;
688 		sc->sc_txdescs[i].gd_addr = 0;
689 	}
690 	GEM_CDTXSYNC(sc, 0, GEM_NTXDESC,
691 	    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
692 
693 	/*
694 	 * Initialize the receive descriptor and receive job
695 	 * descriptor rings.
696 	 */
697 	for (i = 0; i < GEM_NRXDESC; i++) {
698 		sc->sc_rxdescs[i].gd_flags = 0;
699 		sc->sc_rxdescs[i].gd_addr = 0;
700 	}
701 	gem_fill_rx_ring(sc);
702 
703 	return (0);
704 }
705 
706 int
707 gem_ringsize(int sz)
708 {
709 	switch (sz) {
710 	case 32:
711 		return GEM_RING_SZ_32;
712 	case 64:
713 		return GEM_RING_SZ_64;
714 	case 128:
715 		return GEM_RING_SZ_128;
716 	case 256:
717 		return GEM_RING_SZ_256;
718 	case 512:
719 		return GEM_RING_SZ_512;
720 	case 1024:
721 		return GEM_RING_SZ_1024;
722 	case 2048:
723 		return GEM_RING_SZ_2048;
724 	case 4096:
725 		return GEM_RING_SZ_4096;
726 	case 8192:
727 		return GEM_RING_SZ_8192;
728 	default:
729 		printf("gem: invalid Receive Descriptor ring size %d\n", sz);
730 		return GEM_RING_SZ_32;
731 	}
732 }
733 
734 /*
735  * Initialization of interface; set up initialization block
736  * and transmit/receive descriptor rings.
737  */
738 int
739 gem_init(struct ifnet *ifp)
740 {
741 
742 	struct gem_softc *sc = (struct gem_softc *)ifp->if_softc;
743 	bus_space_tag_t t = sc->sc_bustag;
744 	bus_space_handle_t h = sc->sc_h1;
745 	int s;
746 	u_int32_t v;
747 
748 	s = splnet();
749 
750 	DPRINTF(sc, ("%s: gem_init: calling stop\n", sc->sc_dev.dv_xname));
751 	/*
752 	 * Initialization sequence. The numbered steps below correspond
753 	 * to the sequence outlined in section 6.3.5.1 in the Ethernet
754 	 * Channel Engine manual (part of the PCIO manual).
755 	 * See also the STP2002-STQ document from Sun Microsystems.
756 	 */
757 
758 	/* step 1 & 2. Reset the Ethernet Channel */
759 	gem_stop(ifp, 0);
760 	gem_reset(sc);
761 	DPRINTF(sc, ("%s: gem_init: restarting\n", sc->sc_dev.dv_xname));
762 
763 	/* Re-initialize the MIF */
764 	gem_mifinit(sc);
765 
766 	/* Call MI reset function if any */
767 	if (sc->sc_hwreset)
768 		(*sc->sc_hwreset)(sc);
769 
770 	/* step 3. Setup data structures in host memory */
771 	gem_meminit(sc);
772 
773 	/* step 4. TX MAC registers & counters */
774 	gem_init_regs(sc);
775 
776 	/* step 5. RX MAC registers & counters */
777 	gem_iff(sc);
778 
779 	/* step 6 & 7. Program Descriptor Ring Base Addresses */
780 	bus_space_write_4(t, h, GEM_TX_RING_PTR_HI,
781 	    (((uint64_t)GEM_CDTXADDR(sc,0)) >> 32));
782 	bus_space_write_4(t, h, GEM_TX_RING_PTR_LO, GEM_CDTXADDR(sc, 0));
783 
784 	bus_space_write_4(t, h, GEM_RX_RING_PTR_HI,
785 	    (((uint64_t)GEM_CDRXADDR(sc,0)) >> 32));
786 	bus_space_write_4(t, h, GEM_RX_RING_PTR_LO, GEM_CDRXADDR(sc, 0));
787 
788 	/* step 8. Global Configuration & Interrupt Mask */
789 	bus_space_write_4(t, h, GEM_INTMASK,
790 		      ~(GEM_INTR_TX_INTME|
791 			GEM_INTR_TX_EMPTY|
792 			GEM_INTR_RX_DONE|GEM_INTR_RX_NOBUF|
793 			GEM_INTR_RX_TAG_ERR|GEM_INTR_PCS|
794 			GEM_INTR_MAC_CONTROL|GEM_INTR_MIF|
795 			GEM_INTR_BERR));
796 	bus_space_write_4(t, h, GEM_MAC_RX_MASK,
797 	    GEM_MAC_RX_DONE|GEM_MAC_RX_FRAME_CNT);
798 	bus_space_write_4(t, h, GEM_MAC_TX_MASK, 0xffff); /* XXXX */
799 	bus_space_write_4(t, h, GEM_MAC_CONTROL_MASK, 0); /* XXXX */
800 
801 	/* step 9. ETX Configuration: use mostly default values */
802 
803 	/* Enable DMA */
804 	v = gem_ringsize(GEM_NTXDESC /*XXX*/);
805 	v |= ((sc->sc_variant == GEM_SUN_ERI ? 0x100 : 0x04ff) << 10) &
806 	    GEM_TX_CONFIG_TXFIFO_TH;
807 	bus_space_write_4(t, h, GEM_TX_CONFIG, v | GEM_TX_CONFIG_TXDMA_EN);
808 	bus_space_write_4(t, h, GEM_TX_KICK, 0);
809 
810 	/* step 10. ERX Configuration */
811 
812 	/* Encode Receive Descriptor ring size: four possible values */
813 	v = gem_ringsize(GEM_NRXDESC /*XXX*/);
814 	/* RX TCP/UDP checksum offset */
815 	v |= ((ETHER_HDR_LEN + sizeof(struct ip)) <<
816 	    GEM_RX_CONFIG_CXM_START_SHFT);
817 	/* Enable DMA */
818 	bus_space_write_4(t, h, GEM_RX_CONFIG,
819 		v|(GEM_THRSH_1024<<GEM_RX_CONFIG_FIFO_THRS_SHIFT)|
820 		(2<<GEM_RX_CONFIG_FBOFF_SHFT)|GEM_RX_CONFIG_RXDMA_EN|
821 		(0<<GEM_RX_CONFIG_CXM_START_SHFT));
822 	/*
823 	 * The following value is for an OFF Threshold of about 3/4 full
824 	 * and an ON Threshold of 1/4 full.
825 	 */
826 	bus_space_write_4(t, h, GEM_RX_PAUSE_THRESH,
827 	    (3 * sc->sc_rxfifosize / 256) |
828 	    ((sc->sc_rxfifosize / 256) << 12));
829 	bus_space_write_4(t, h, GEM_RX_BLANKING, (6 << 12) | 6);
830 
831 	/* step 11. Configure Media */
832 	mii_mediachg(&sc->sc_mii);
833 
834 	/* step 12. RX_MAC Configuration Register */
835 	v = bus_space_read_4(t, h, GEM_MAC_RX_CONFIG);
836 	v |= GEM_MAC_RX_ENABLE | GEM_MAC_RX_STRIP_CRC;
837 	bus_space_write_4(t, h, GEM_MAC_RX_CONFIG, v);
838 
839 	/* step 14. Issue Transmit Pending command */
840 
841 	/* Call MI initialization function if any */
842 	if (sc->sc_hwinit)
843 		(*sc->sc_hwinit)(sc);
844 
845 	/* step 15.  Give the receiver a swift kick */
846 	bus_space_write_4(t, h, GEM_RX_KICK, sc->sc_rx_prod);
847 
848 	/* Start the one second timer. */
849 	timeout_add_sec(&sc->sc_tick_ch, 1);
850 
851 	ifp->if_flags |= IFF_RUNNING;
852 	ifp->if_flags &= ~IFF_OACTIVE;
853 
854 	splx(s);
855 
856 	return (0);
857 }
858 
859 void
860 gem_init_regs(struct gem_softc *sc)
861 {
862 	bus_space_tag_t t = sc->sc_bustag;
863 	bus_space_handle_t h = sc->sc_h1;
864 	u_int32_t v;
865 
866 	/* These regs are not cleared on reset */
867 	sc->sc_inited = 0;
868 	if (!sc->sc_inited) {
869 		/* Load recommended values */
870 		bus_space_write_4(t, h, GEM_MAC_IPG0, 0x00);
871 		bus_space_write_4(t, h, GEM_MAC_IPG1, 0x08);
872 		bus_space_write_4(t, h, GEM_MAC_IPG2, 0x04);
873 
874 		bus_space_write_4(t, h, GEM_MAC_MAC_MIN_FRAME, ETHER_MIN_LEN);
875 		/* Max frame and max burst size */
876 		bus_space_write_4(t, h, GEM_MAC_MAC_MAX_FRAME,
877 		    (ETHER_MAX_LEN + ETHER_VLAN_ENCAP_LEN) | (0x2000 << 16));
878 
879 		bus_space_write_4(t, h, GEM_MAC_PREAMBLE_LEN, 0x07);
880 		bus_space_write_4(t, h, GEM_MAC_JAM_SIZE, 0x04);
881 		bus_space_write_4(t, h, GEM_MAC_ATTEMPT_LIMIT, 0x10);
882 		bus_space_write_4(t, h, GEM_MAC_CONTROL_TYPE, 0x8088);
883 		bus_space_write_4(t, h, GEM_MAC_RANDOM_SEED,
884 		    ((sc->sc_arpcom.ac_enaddr[5]<<8)|sc->sc_arpcom.ac_enaddr[4])&0x3ff);
885 
886 		/* Secondary MAC addr set to 0:0:0:0:0:0 */
887 		bus_space_write_4(t, h, GEM_MAC_ADDR3, 0);
888 		bus_space_write_4(t, h, GEM_MAC_ADDR4, 0);
889 		bus_space_write_4(t, h, GEM_MAC_ADDR5, 0);
890 
891 		/* MAC control addr set to 0:1:c2:0:1:80 */
892 		bus_space_write_4(t, h, GEM_MAC_ADDR6, 0x0001);
893 		bus_space_write_4(t, h, GEM_MAC_ADDR7, 0xc200);
894 		bus_space_write_4(t, h, GEM_MAC_ADDR8, 0x0180);
895 
896 		/* MAC filter addr set to 0:0:0:0:0:0 */
897 		bus_space_write_4(t, h, GEM_MAC_ADDR_FILTER0, 0);
898 		bus_space_write_4(t, h, GEM_MAC_ADDR_FILTER1, 0);
899 		bus_space_write_4(t, h, GEM_MAC_ADDR_FILTER2, 0);
900 
901 		bus_space_write_4(t, h, GEM_MAC_ADR_FLT_MASK1_2, 0);
902 		bus_space_write_4(t, h, GEM_MAC_ADR_FLT_MASK0, 0);
903 
904 		sc->sc_inited = 1;
905 	}
906 
907 	/* Counters need to be zeroed */
908 	bus_space_write_4(t, h, GEM_MAC_NORM_COLL_CNT, 0);
909 	bus_space_write_4(t, h, GEM_MAC_FIRST_COLL_CNT, 0);
910 	bus_space_write_4(t, h, GEM_MAC_EXCESS_COLL_CNT, 0);
911 	bus_space_write_4(t, h, GEM_MAC_LATE_COLL_CNT, 0);
912 	bus_space_write_4(t, h, GEM_MAC_DEFER_TMR_CNT, 0);
913 	bus_space_write_4(t, h, GEM_MAC_PEAK_ATTEMPTS, 0);
914 	bus_space_write_4(t, h, GEM_MAC_RX_FRAME_COUNT, 0);
915 	bus_space_write_4(t, h, GEM_MAC_RX_LEN_ERR_CNT, 0);
916 	bus_space_write_4(t, h, GEM_MAC_RX_ALIGN_ERR, 0);
917 	bus_space_write_4(t, h, GEM_MAC_RX_CRC_ERR_CNT, 0);
918 	bus_space_write_4(t, h, GEM_MAC_RX_CODE_VIOL, 0);
919 
920 	/* Set XOFF PAUSE time */
921 	bus_space_write_4(t, h, GEM_MAC_SEND_PAUSE_CMD, 0x1bf0);
922 
923 	/*
924 	 * Set the internal arbitration to "infinite" bursts of the
925 	 * maximum length of 31 * 64 bytes so DMA transfers aren't
926 	 * split up in cache line size chunks. This greatly improves
927 	 * especially RX performance.
928 	 * Enable silicon bug workarounds for the Apple variants.
929 	 */
930 	v = GEM_CONFIG_TXDMA_LIMIT | GEM_CONFIG_RXDMA_LIMIT;
931 	if (sc->sc_pci)
932 		v |= GEM_CONFIG_BURST_INF;
933 	else
934 		v |= GEM_CONFIG_BURST_64;
935 	if (sc->sc_variant != GEM_SUN_GEM && sc->sc_variant != GEM_SUN_ERI)
936 		v |= GEM_CONFIG_RONPAULBIT | GEM_CONFIG_BUG2FIX;
937 	bus_space_write_4(t, h, GEM_CONFIG, v);
938 
939 	/*
940 	 * Set the station address.
941 	 */
942 	bus_space_write_4(t, h, GEM_MAC_ADDR0,
943 		(sc->sc_arpcom.ac_enaddr[4]<<8) | sc->sc_arpcom.ac_enaddr[5]);
944 	bus_space_write_4(t, h, GEM_MAC_ADDR1,
945 		(sc->sc_arpcom.ac_enaddr[2]<<8) | sc->sc_arpcom.ac_enaddr[3]);
946 	bus_space_write_4(t, h, GEM_MAC_ADDR2,
947 		(sc->sc_arpcom.ac_enaddr[0]<<8) | sc->sc_arpcom.ac_enaddr[1]);
948 }
949 
950 /*
951  * RX TCP/UDP checksum
952  */
953 void
954 gem_rxcksum(struct mbuf *m, u_int64_t rxstat)
955 {
956 	struct ether_header *eh;
957 	struct ip *ip;
958 	struct udphdr *uh;
959 	int32_t hlen, len, pktlen;
960 	u_int16_t cksum, *opts;
961 	u_int32_t temp32;
962 	union pseudoh {
963 		struct hdr {
964 			u_int16_t len;
965 			u_int8_t ttl;
966 			u_int8_t proto;
967 			u_int32_t src;
968 			u_int32_t dst;
969 		} h;
970 		u_int16_t w[6];
971 	} ph;
972 
973 	pktlen = m->m_pkthdr.len;
974 	if (pktlen < sizeof(struct ether_header))
975 		return;
976 	eh = mtod(m, struct ether_header *);
977 	if (eh->ether_type != htons(ETHERTYPE_IP))
978 		return;
979 	ip = (struct ip *)(eh + 1);
980 	if (ip->ip_v != IPVERSION)
981 		return;
982 
983 	hlen = ip->ip_hl << 2;
984 	pktlen -= sizeof(struct ether_header);
985 	if (hlen < sizeof(struct ip))
986 		return;
987 	if (ntohs(ip->ip_len) < hlen)
988 		return;
989 	if (ntohs(ip->ip_len) != pktlen)
990 		return;
991 	if (ip->ip_off & htons(IP_MF | IP_OFFMASK))
992 		return;	/* can't handle fragmented packet */
993 
994 	switch (ip->ip_p) {
995 	case IPPROTO_TCP:
996 		if (pktlen < (hlen + sizeof(struct tcphdr)))
997 			return;
998 		break;
999 	case IPPROTO_UDP:
1000 		if (pktlen < (hlen + sizeof(struct udphdr)))
1001 			return;
1002 		uh = (struct udphdr *)((caddr_t)ip + hlen);
1003 		if (uh->uh_sum == 0)
1004 			return; /* no checksum */
1005 		break;
1006 	default:
1007 		return;
1008 	}
1009 
1010 	cksum = htons(~(rxstat & GEM_RD_CHECKSUM));
1011 	/* cksum fixup for IP options */
1012 	len = hlen - sizeof(struct ip);
1013 	if (len > 0) {
1014 		opts = (u_int16_t *)(ip + 1);
1015 		for (; len > 0; len -= sizeof(u_int16_t), opts++) {
1016 			temp32 = cksum - *opts;
1017 			temp32 = (temp32 >> 16) + (temp32 & 65535);
1018 			cksum = temp32 & 65535;
1019 		}
1020 	}
1021 
1022 	ph.h.len = htons(ntohs(ip->ip_len) - hlen);
1023 	ph.h.ttl = 0;
1024 	ph.h.proto = ip->ip_p;
1025 	ph.h.src = ip->ip_src.s_addr;
1026 	ph.h.dst = ip->ip_dst.s_addr;
1027 	temp32 = cksum;
1028 	opts = &ph.w[0];
1029 	temp32 += opts[0] + opts[1] + opts[2] + opts[3] + opts[4] + opts[5];
1030 	temp32 = (temp32 >> 16) + (temp32 & 65535);
1031 	temp32 += (temp32 >> 16);
1032 	cksum = ~temp32;
1033 	if (cksum == 0) {
1034 		m->m_pkthdr.csum_flags |=
1035 			M_TCP_CSUM_IN_OK | M_UDP_CSUM_IN_OK;
1036 	}
1037 }
1038 
1039 /*
1040  * Receive interrupt.
1041  */
1042 int
1043 gem_rint(struct gem_softc *sc)
1044 {
1045 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1046 	bus_space_tag_t t = sc->sc_bustag;
1047 	bus_space_handle_t h = sc->sc_h1;
1048 	struct gem_rxsoft *rxs;
1049 	struct mbuf *m;
1050 	u_int64_t rxstat;
1051 	int i, len;
1052 
1053 	for (i = sc->sc_rx_cons; sc->sc_rx_cnt > 0; i = GEM_NEXTRX(i)) {
1054 		rxs = &sc->sc_rxsoft[i];
1055 
1056 		GEM_CDRXSYNC(sc, i,
1057 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1058 
1059 		rxstat = GEM_DMA_READ(sc, &sc->sc_rxdescs[i].gd_flags);
1060 
1061 		if (rxstat & GEM_RD_OWN) {
1062 			/* We have processed all of the receive buffers. */
1063 			break;
1064 		}
1065 
1066 		bus_dmamap_sync(sc->sc_dmatag, rxs->rxs_dmamap, 0,
1067 		    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);
1068 		bus_dmamap_unload(sc->sc_dmatag, rxs->rxs_dmamap);
1069 
1070 		m = rxs->rxs_mbuf;
1071 		rxs->rxs_mbuf = NULL;
1072 
1073 		sc->sc_rx_cnt--;
1074 
1075 		if (rxstat & GEM_RD_BAD_CRC) {
1076 			ifp->if_ierrors++;
1077 #ifdef GEM_DEBUG
1078 			printf("%s: receive error: CRC error\n",
1079 				sc->sc_dev.dv_xname);
1080 #endif
1081 			m_freem(m);
1082 			continue;
1083 		}
1084 
1085 #ifdef GEM_DEBUG
1086 		if (ifp->if_flags & IFF_DEBUG) {
1087 			printf("    rxsoft %p descriptor %d: ", rxs, i);
1088 			printf("gd_flags: 0x%016llx\t", (long long)
1089 				GEM_DMA_READ(sc, &sc->sc_rxdescs[i].gd_flags));
1090 			printf("gd_addr: 0x%016llx\n", (long long)
1091 				GEM_DMA_READ(sc, &sc->sc_rxdescs[i].gd_addr));
1092 		}
1093 #endif
1094 
1095 		/* No errors; receive the packet. */
1096 		len = GEM_RD_BUFLEN(rxstat);
1097 
1098 		m->m_data += 2; /* We're already off by two */
1099 
1100 		ifp->if_ipackets++;
1101 		m->m_pkthdr.rcvif = ifp;
1102 		m->m_pkthdr.len = m->m_len = len;
1103 
1104 		gem_rxcksum(m, rxstat);
1105 
1106 #if NBPFILTER > 0
1107 		if (ifp->if_bpf)
1108 			bpf_mtap(ifp->if_bpf, m, BPF_DIRECTION_IN);
1109 #endif /* NBPFILTER > 0 */
1110 
1111 		/* Pass it on. */
1112 		ether_input_mbuf(ifp, m);
1113 	}
1114 
1115 	/* Update the receive pointer. */
1116 	sc->sc_rx_cons = i;
1117 	gem_fill_rx_ring(sc);
1118 	bus_space_write_4(t, h, GEM_RX_KICK, sc->sc_rx_prod);
1119 
1120 	DPRINTF(sc, ("gem_rint: done sc->sc_rx_cons %d, complete %d\n",
1121 		sc->sc_rx_cons, bus_space_read_4(t, h, GEM_RX_COMPLETION)));
1122 
1123 	return (1);
1124 }
1125 
1126 void
1127 gem_fill_rx_ring(struct gem_softc *sc)
1128 {
1129 	while (sc->sc_rx_cnt < (GEM_NRXDESC - 4)) {
1130 		if (gem_add_rxbuf(sc, sc->sc_rx_prod))
1131 			break;
1132 	}
1133 }
1134 
1135 /*
1136  * Add a receive buffer to the indicated descriptor.
1137  */
1138 int
1139 gem_add_rxbuf(struct gem_softc *sc, int idx)
1140 {
1141 	struct gem_rxsoft *rxs = &sc->sc_rxsoft[idx];
1142 	struct mbuf *m;
1143 	int error;
1144 
1145 	m = MCLGETI(NULL, M_DONTWAIT, &sc->sc_arpcom.ac_if, MCLBYTES);
1146 	if (!m)
1147 		return (ENOBUFS);
1148 	m->m_len = m->m_pkthdr.len = MCLBYTES;
1149 
1150 #ifdef GEM_DEBUG
1151 /* bzero the packet to check dma */
1152 	memset(m->m_ext.ext_buf, 0, m->m_ext.ext_size);
1153 #endif
1154 
1155 	rxs->rxs_mbuf = m;
1156 
1157 	error = bus_dmamap_load_mbuf(sc->sc_dmatag, rxs->rxs_dmamap, m,
1158 	    BUS_DMA_READ|BUS_DMA_NOWAIT);
1159 	if (error) {
1160 		printf("%s: can't load rx DMA map %d, error = %d\n",
1161 		    sc->sc_dev.dv_xname, idx, error);
1162 		panic("gem_add_rxbuf");	/* XXX */
1163 	}
1164 
1165 	bus_dmamap_sync(sc->sc_dmatag, rxs->rxs_dmamap, 0,
1166 	    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
1167 
1168 	GEM_INIT_RXDESC(sc, idx);
1169 
1170 	sc->sc_rx_prod = GEM_NEXTRX(sc->sc_rx_prod);
1171 	sc->sc_rx_cnt++;
1172 
1173 	return (0);
1174 }
1175 
1176 int
1177 gem_eint(struct gem_softc *sc, u_int status)
1178 {
1179 	if ((status & GEM_INTR_MIF) != 0) {
1180 #ifdef GEM_DEBUG
1181 		printf("%s: link status changed\n", sc->sc_dev.dv_xname);
1182 #endif
1183 		return (1);
1184 	}
1185 
1186 	printf("%s: status=%b\n", sc->sc_dev.dv_xname, status, GEM_INTR_BITS);
1187 	return (1);
1188 }
1189 
1190 int
1191 gem_pint(struct gem_softc *sc)
1192 {
1193 	bus_space_tag_t t = sc->sc_bustag;
1194 	bus_space_handle_t seb = sc->sc_h1;
1195 	u_int32_t status;
1196 
1197 	status = bus_space_read_4(t, seb, GEM_MII_INTERRUP_STATUS);
1198 	status |= bus_space_read_4(t, seb, GEM_MII_INTERRUP_STATUS);
1199 #ifdef GEM_DEBUG
1200 	if (status)
1201 		printf("%s: link status changed\n", sc->sc_dev.dv_xname);
1202 #endif
1203 	return (1);
1204 }
1205 
1206 int
1207 gem_intr(void *v)
1208 {
1209 	struct gem_softc *sc = (struct gem_softc *)v;
1210 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1211 	bus_space_tag_t t = sc->sc_bustag;
1212 	bus_space_handle_t seb = sc->sc_h1;
1213 	u_int32_t status;
1214 	int r = 0;
1215 
1216 	status = bus_space_read_4(t, seb, GEM_STATUS);
1217 	DPRINTF(sc, ("%s: gem_intr: cplt %xstatus %b\n",
1218 		sc->sc_dev.dv_xname, (status>>19), status, GEM_INTR_BITS));
1219 
1220 	if (status == 0xffffffff)
1221 		return (0);
1222 
1223 	if ((status & GEM_INTR_PCS) != 0)
1224 		r |= gem_pint(sc);
1225 
1226 	if ((status & (GEM_INTR_RX_TAG_ERR | GEM_INTR_BERR)) != 0)
1227 		r |= gem_eint(sc, status);
1228 
1229 	if ((status & (GEM_INTR_TX_EMPTY | GEM_INTR_TX_INTME)) != 0)
1230 		r |= gem_tint(sc, status);
1231 
1232 	if ((status & (GEM_INTR_RX_DONE | GEM_INTR_RX_NOBUF)) != 0)
1233 		r |= gem_rint(sc);
1234 
1235 	/* We should eventually do more than just print out error stats. */
1236 	if (status & GEM_INTR_TX_MAC) {
1237 		int txstat = bus_space_read_4(t, seb, GEM_MAC_TX_STATUS);
1238 #ifdef GEM_DEBUG
1239 		if (txstat & ~GEM_MAC_TX_XMIT_DONE)
1240 			printf("%s: MAC tx fault, status %x\n",
1241 			    sc->sc_dev.dv_xname, txstat);
1242 #endif
1243 		if (txstat & (GEM_MAC_TX_UNDERRUN | GEM_MAC_TX_PKT_TOO_LONG))
1244 			gem_init(ifp);
1245 	}
1246 	if (status & GEM_INTR_RX_MAC) {
1247 		int rxstat = bus_space_read_4(t, seb, GEM_MAC_RX_STATUS);
1248 #ifdef GEM_DEBUG
1249  		if (rxstat & ~GEM_MAC_RX_DONE)
1250  			printf("%s: MAC rx fault, status %x\n",
1251  			    sc->sc_dev.dv_xname, rxstat);
1252 #endif
1253 		if (rxstat & GEM_MAC_RX_OVERFLOW) {
1254 			ifp->if_ierrors++;
1255 
1256 			/*
1257 			 * Apparently a silicon bug causes ERI to hang
1258 			 * from time to time.  So if we detect an RX
1259 			 * FIFO overflow, we fire off a timer, and
1260 			 * check whether we're still making progress
1261 			 * by looking at the RX FIFO write and read
1262 			 * pointers.
1263 			 */
1264 			sc->sc_rx_fifo_wr_ptr =
1265 				bus_space_read_4(t, seb, GEM_RX_FIFO_WR_PTR);
1266 			sc->sc_rx_fifo_rd_ptr =
1267 				bus_space_read_4(t, seb, GEM_RX_FIFO_RD_PTR);
1268 			timeout_add_msec(&sc->sc_rx_watchdog, 400);
1269 		}
1270 #ifdef GEM_DEBUG
1271 		else if (rxstat & ~(GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT))
1272 			printf("%s: MAC rx fault, status %x\n",
1273 			    sc->sc_dev.dv_xname, rxstat);
1274 #endif
1275 	}
1276 	return (r);
1277 }
1278 
1279 void
1280 gem_rx_watchdog(void *arg)
1281 {
1282 	struct gem_softc *sc = arg;
1283 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1284 	bus_space_tag_t t = sc->sc_bustag;
1285 	bus_space_handle_t h = sc->sc_h1;
1286 	u_int32_t rx_fifo_wr_ptr;
1287 	u_int32_t rx_fifo_rd_ptr;
1288 	u_int32_t state;
1289 
1290 	if ((ifp->if_flags & IFF_RUNNING) == 0)
1291 		return;
1292 
1293 	rx_fifo_wr_ptr = bus_space_read_4(t, h, GEM_RX_FIFO_WR_PTR);
1294 	rx_fifo_rd_ptr = bus_space_read_4(t, h, GEM_RX_FIFO_RD_PTR);
1295 	state = bus_space_read_4(t, h, GEM_MAC_MAC_STATE);
1296 	if ((state & GEM_MAC_STATE_OVERFLOW) == GEM_MAC_STATE_OVERFLOW &&
1297 	    ((rx_fifo_wr_ptr == rx_fifo_rd_ptr) ||
1298 	     ((sc->sc_rx_fifo_wr_ptr == rx_fifo_wr_ptr) &&
1299 	      (sc->sc_rx_fifo_rd_ptr == rx_fifo_rd_ptr)))) {
1300 		/*
1301 		 * The RX state machine is still in overflow state and
1302 		 * the RX FIFO write and read pointers seem to be
1303 		 * stuck.  Whack the chip over the head to get things
1304 		 * going again.
1305 		 */
1306 		gem_init(ifp);
1307 	}
1308 }
1309 
1310 void
1311 gem_watchdog(struct ifnet *ifp)
1312 {
1313 	struct gem_softc *sc = ifp->if_softc;
1314 
1315 	DPRINTF(sc, ("gem_watchdog: GEM_RX_CONFIG %x GEM_MAC_RX_STATUS %x "
1316 		"GEM_MAC_RX_CONFIG %x\n",
1317 		bus_space_read_4(sc->sc_bustag, sc->sc_h1, GEM_RX_CONFIG),
1318 		bus_space_read_4(sc->sc_bustag, sc->sc_h1, GEM_MAC_RX_STATUS),
1319 		bus_space_read_4(sc->sc_bustag, sc->sc_h1, GEM_MAC_RX_CONFIG)));
1320 
1321 	log(LOG_ERR, "%s: device timeout\n", sc->sc_dev.dv_xname);
1322 	++ifp->if_oerrors;
1323 
1324 	/* Try to get more packets going. */
1325 	gem_init(ifp);
1326 }
1327 
1328 /*
1329  * Initialize the MII Management Interface
1330  */
1331 void
1332 gem_mifinit(struct gem_softc *sc)
1333 {
1334 	bus_space_tag_t t = sc->sc_bustag;
1335 	bus_space_handle_t mif = sc->sc_h1;
1336 
1337 	/* Configure the MIF in frame mode */
1338 	sc->sc_mif_config = bus_space_read_4(t, mif, GEM_MIF_CONFIG);
1339 	sc->sc_mif_config &= ~GEM_MIF_CONFIG_BB_ENA;
1340 	bus_space_write_4(t, mif, GEM_MIF_CONFIG, sc->sc_mif_config);
1341 }
1342 
1343 /*
1344  * MII interface
1345  *
1346  * The GEM MII interface supports at least three different operating modes:
1347  *
1348  * Bitbang mode is implemented using data, clock and output enable registers.
1349  *
1350  * Frame mode is implemented by loading a complete frame into the frame
1351  * register and polling the valid bit for completion.
1352  *
1353  * Polling mode uses the frame register but completion is indicated by
1354  * an interrupt.
1355  *
1356  */
1357 int
1358 gem_mii_readreg(struct device *self, int phy, int reg)
1359 {
1360 	struct gem_softc *sc = (void *)self;
1361 	bus_space_tag_t t = sc->sc_bustag;
1362 	bus_space_handle_t mif = sc->sc_h1;
1363 	int n;
1364 	u_int32_t v;
1365 
1366 #ifdef GEM_DEBUG
1367 	if (sc->sc_debug)
1368 		printf("gem_mii_readreg: phy %d reg %d\n", phy, reg);
1369 #endif
1370 
1371 	/* Construct the frame command */
1372 	v = (reg << GEM_MIF_REG_SHIFT)	| (phy << GEM_MIF_PHY_SHIFT) |
1373 		GEM_MIF_FRAME_READ;
1374 
1375 	bus_space_write_4(t, mif, GEM_MIF_FRAME, v);
1376 	for (n = 0; n < 100; n++) {
1377 		DELAY(1);
1378 		v = bus_space_read_4(t, mif, GEM_MIF_FRAME);
1379 		if (v & GEM_MIF_FRAME_TA0)
1380 			return (v & GEM_MIF_FRAME_DATA);
1381 	}
1382 
1383 	printf("%s: mii_read timeout\n", sc->sc_dev.dv_xname);
1384 	return (0);
1385 }
1386 
1387 void
1388 gem_mii_writereg(struct device *self, int phy, int reg, int val)
1389 {
1390 	struct gem_softc *sc = (void *)self;
1391 	bus_space_tag_t t = sc->sc_bustag;
1392 	bus_space_handle_t mif = sc->sc_h1;
1393 	int n;
1394 	u_int32_t v;
1395 
1396 #ifdef GEM_DEBUG
1397 	if (sc->sc_debug)
1398 		printf("gem_mii_writereg: phy %d reg %d val %x\n",
1399 			phy, reg, val);
1400 #endif
1401 
1402 	/* Construct the frame command */
1403 	v = GEM_MIF_FRAME_WRITE			|
1404 	    (phy << GEM_MIF_PHY_SHIFT)		|
1405 	    (reg << GEM_MIF_REG_SHIFT)		|
1406 	    (val & GEM_MIF_FRAME_DATA);
1407 
1408 	bus_space_write_4(t, mif, GEM_MIF_FRAME, v);
1409 	for (n = 0; n < 100; n++) {
1410 		DELAY(1);
1411 		v = bus_space_read_4(t, mif, GEM_MIF_FRAME);
1412 		if (v & GEM_MIF_FRAME_TA0)
1413 			return;
1414 	}
1415 
1416 	printf("%s: mii_write timeout\n", sc->sc_dev.dv_xname);
1417 }
1418 
1419 void
1420 gem_mii_statchg(struct device *dev)
1421 {
1422 	struct gem_softc *sc = (void *)dev;
1423 #ifdef GEM_DEBUG
1424 	int instance = IFM_INST(sc->sc_mii.mii_media.ifm_cur->ifm_media);
1425 #endif
1426 	bus_space_tag_t t = sc->sc_bustag;
1427 	bus_space_handle_t mac = sc->sc_h1;
1428 	u_int32_t v;
1429 
1430 #ifdef GEM_DEBUG
1431 	if (sc->sc_debug)
1432 		printf("gem_mii_statchg: status change: phy = %d\n", instance);
1433 #endif
1434 
1435 	/* Set tx full duplex options */
1436 	bus_space_write_4(t, mac, GEM_MAC_TX_CONFIG, 0);
1437 	delay(10000); /* reg must be cleared and delay before changing. */
1438 	v = GEM_MAC_TX_ENA_IPG0|GEM_MAC_TX_NGU|GEM_MAC_TX_NGU_LIMIT|
1439 		GEM_MAC_TX_ENABLE;
1440 	if ((IFM_OPTIONS(sc->sc_mii.mii_media_active) & IFM_FDX) != 0) {
1441 		v |= GEM_MAC_TX_IGN_CARRIER|GEM_MAC_TX_IGN_COLLIS;
1442 	}
1443 	bus_space_write_4(t, mac, GEM_MAC_TX_CONFIG, v);
1444 
1445 	/* XIF Configuration */
1446 	v = GEM_MAC_XIF_TX_MII_ENA;
1447 	v |= GEM_MAC_XIF_LINK_LED;
1448 
1449 	/* External MII needs echo disable if half duplex. */
1450 	if ((IFM_OPTIONS(sc->sc_mii.mii_media_active) & IFM_FDX) != 0)
1451 		/* turn on full duplex LED */
1452 		v |= GEM_MAC_XIF_FDPLX_LED;
1453 	else
1454 		/* half duplex -- disable echo */
1455 		v |= GEM_MAC_XIF_ECHO_DISABL;
1456 
1457 	switch (IFM_SUBTYPE(sc->sc_mii.mii_media_active)) {
1458 	case IFM_1000_T:  /* Gigabit using GMII interface */
1459 	case IFM_1000_SX:
1460 		v |= GEM_MAC_XIF_GMII_MODE;
1461 		break;
1462 	default:
1463 		v &= ~GEM_MAC_XIF_GMII_MODE;
1464 	}
1465 	bus_space_write_4(t, mac, GEM_MAC_XIF_CONFIG, v);
1466 
1467 	/*
1468 	 * 802.3x flow control
1469 	 */
1470 	v = bus_space_read_4(t, mac, GEM_MAC_CONTROL_CONFIG);
1471 	v &= ~(GEM_MAC_CC_RX_PAUSE | GEM_MAC_CC_TX_PAUSE);
1472 	if ((IFM_OPTIONS(sc->sc_mii.mii_media_active) & IFM_ETH_RXPAUSE) != 0)
1473 		v |= GEM_MAC_CC_RX_PAUSE;
1474 	if ((IFM_OPTIONS(sc->sc_mii.mii_media_active) & IFM_ETH_TXPAUSE) != 0)
1475 		v |= GEM_MAC_CC_TX_PAUSE;
1476 	bus_space_write_4(t, mac, GEM_MAC_CONTROL_CONFIG, v);
1477 }
1478 
1479 int
1480 gem_pcs_readreg(struct device *self, int phy, int reg)
1481 {
1482 	struct gem_softc *sc = (void *)self;
1483 	bus_space_tag_t t = sc->sc_bustag;
1484 	bus_space_handle_t pcs = sc->sc_h1;
1485 
1486 #ifdef GEM_DEBUG
1487 	if (sc->sc_debug)
1488 		printf("gem_pcs_readreg: phy %d reg %d\n", phy, reg);
1489 #endif
1490 
1491 	if (phy != GEM_PHYAD_EXTERNAL)
1492 		return (0);
1493 
1494 	switch (reg) {
1495 	case MII_BMCR:
1496 		reg = GEM_MII_CONTROL;
1497 		break;
1498 	case MII_BMSR:
1499 		reg = GEM_MII_STATUS;
1500 		break;
1501 	case MII_ANAR:
1502 		reg = GEM_MII_ANAR;
1503 		break;
1504 	case MII_ANLPAR:
1505 		reg = GEM_MII_ANLPAR;
1506 		break;
1507 	case MII_EXTSR:
1508 		return (EXTSR_1000XFDX|EXTSR_1000XHDX);
1509 	default:
1510 		return (0);
1511 	}
1512 
1513 	return bus_space_read_4(t, pcs, reg);
1514 }
1515 
1516 void
1517 gem_pcs_writereg(struct device *self, int phy, int reg, int val)
1518 {
1519 	struct gem_softc *sc = (void *)self;
1520 	bus_space_tag_t t = sc->sc_bustag;
1521 	bus_space_handle_t pcs = sc->sc_h1;
1522 	int reset = 0;
1523 
1524 #ifdef GEM_DEBUG
1525 	if (sc->sc_debug)
1526 		printf("gem_pcs_writereg: phy %d reg %d val %x\n",
1527 			phy, reg, val);
1528 #endif
1529 
1530 	if (phy != GEM_PHYAD_EXTERNAL)
1531 		return;
1532 
1533 	if (reg == MII_ANAR)
1534 		bus_space_write_4(t, pcs, GEM_MII_CONFIG, 0);
1535 
1536 	switch (reg) {
1537 	case MII_BMCR:
1538 		reset = (val & GEM_MII_CONTROL_RESET);
1539 		reg = GEM_MII_CONTROL;
1540 		break;
1541 	case MII_BMSR:
1542 		reg = GEM_MII_STATUS;
1543 		break;
1544 	case MII_ANAR:
1545 		reg = GEM_MII_ANAR;
1546 		break;
1547 	case MII_ANLPAR:
1548 		reg = GEM_MII_ANLPAR;
1549 		break;
1550 	default:
1551 		return;
1552 	}
1553 
1554 	bus_space_write_4(t, pcs, reg, val);
1555 
1556 	if (reset)
1557 		gem_bitwait(sc, pcs, GEM_MII_CONTROL, GEM_MII_CONTROL_RESET, 0);
1558 
1559 	if (reg == GEM_MII_ANAR || reset) {
1560 		bus_space_write_4(t, pcs, GEM_MII_SLINK_CONTROL,
1561 		    GEM_MII_SLINK_LOOPBACK|GEM_MII_SLINK_EN_SYNC_D);
1562 		bus_space_write_4(t, pcs, GEM_MII_CONFIG,
1563 		    GEM_MII_CONFIG_ENABLE);
1564 	}
1565 }
1566 
1567 int
1568 gem_mediachange(struct ifnet *ifp)
1569 {
1570 	struct gem_softc *sc = ifp->if_softc;
1571 	struct mii_data *mii = &sc->sc_mii;
1572 
1573 	if (mii->mii_instance) {
1574 		struct mii_softc *miisc;
1575 		LIST_FOREACH(miisc, &mii->mii_phys, mii_list)
1576 			mii_phy_reset(miisc);
1577 	}
1578 
1579 	return (mii_mediachg(&sc->sc_mii));
1580 }
1581 
1582 void
1583 gem_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
1584 {
1585 	struct gem_softc *sc = ifp->if_softc;
1586 
1587 	mii_pollstat(&sc->sc_mii);
1588 	ifmr->ifm_active = sc->sc_mii.mii_media_active;
1589 	ifmr->ifm_status = sc->sc_mii.mii_media_status;
1590 }
1591 
1592 /*
1593  * Process an ioctl request.
1594  */
1595 int
1596 gem_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
1597 {
1598 	struct gem_softc *sc = ifp->if_softc;
1599 	struct ifaddr *ifa = (struct ifaddr *)data;
1600 	struct ifreq *ifr = (struct ifreq *)data;
1601 	int s, error = 0;
1602 
1603 	s = splnet();
1604 
1605 	switch (cmd) {
1606 	case SIOCSIFADDR:
1607 		ifp->if_flags |= IFF_UP;
1608 		if ((ifp->if_flags & IFF_RUNNING) == 0)
1609 			gem_init(ifp);
1610 #ifdef INET
1611 		if (ifa->ifa_addr->sa_family == AF_INET)
1612 			arp_ifinit(&sc->sc_arpcom, ifa);
1613 #endif
1614 		break;
1615 
1616 	case SIOCSIFFLAGS:
1617 		if (ifp->if_flags & IFF_UP) {
1618 			if (ifp->if_flags & IFF_RUNNING)
1619 				error = ENETRESET;
1620 			else
1621 				gem_init(ifp);
1622 		} else {
1623 			if (ifp->if_flags & IFF_RUNNING)
1624 				gem_stop(ifp, 0);
1625 		}
1626 #ifdef GEM_DEBUG
1627 		sc->sc_debug = (ifp->if_flags & IFF_DEBUG) != 0 ? 1 : 0;
1628 #endif
1629 		break;
1630 
1631 	case SIOCGIFMEDIA:
1632 	case SIOCSIFMEDIA:
1633 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_media, cmd);
1634 		break;
1635 
1636 	default:
1637 		error = ether_ioctl(ifp, &sc->sc_arpcom, cmd, data);
1638 	}
1639 
1640 	if (error == ENETRESET) {
1641 		if (ifp->if_flags & IFF_RUNNING)
1642 			gem_iff(sc);
1643 		error = 0;
1644 	}
1645 
1646 	splx(s);
1647 	return (error);
1648 }
1649 
1650 void
1651 gem_iff(struct gem_softc *sc)
1652 {
1653 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1654 	struct arpcom *ac = &sc->sc_arpcom;
1655 	struct ether_multi *enm;
1656 	struct ether_multistep step;
1657 	bus_space_tag_t t = sc->sc_bustag;
1658 	bus_space_handle_t h = sc->sc_h1;
1659 	u_int32_t crc, hash[16], rxcfg;
1660 	int i;
1661 
1662 	rxcfg = bus_space_read_4(t, h, GEM_MAC_RX_CONFIG);
1663 	rxcfg &= ~(GEM_MAC_RX_HASH_FILTER | GEM_MAC_RX_PROMISCUOUS |
1664 	    GEM_MAC_RX_PROMISC_GRP);
1665 	ifp->if_flags &= ~IFF_ALLMULTI;
1666 
1667 	if (ifp->if_flags & IFF_PROMISC || ac->ac_multirangecnt > 0) {
1668 		ifp->if_flags |= IFF_ALLMULTI;
1669 		if (ifp->if_flags & IFF_PROMISC)
1670 			rxcfg |= GEM_MAC_RX_PROMISCUOUS;
1671 		else
1672 			rxcfg |= GEM_MAC_RX_PROMISC_GRP;
1673 	} else {
1674 		/*
1675 		 * Set up multicast address filter by passing all multicast
1676 		 * addresses through a crc generator, and then using the
1677 		 * high order 8 bits as an index into the 256 bit logical
1678 		 * address filter.  The high order 4 bits selects the word,
1679 		 * while the other 4 bits select the bit within the word
1680 		 * (where bit 0 is the MSB).
1681 		 */
1682 
1683 		rxcfg |= GEM_MAC_RX_HASH_FILTER;
1684 
1685 		/* Clear hash table */
1686 		for (i = 0; i < 16; i++)
1687 			hash[i] = 0;
1688 
1689 		ETHER_FIRST_MULTI(step, ac, enm);
1690 		while (enm != NULL) {
1691 			crc = ether_crc32_le(enm->enm_addrlo,
1692 			    ETHER_ADDR_LEN);
1693 
1694 			/* Just want the 8 most significant bits. */
1695 			crc >>= 24;
1696 
1697 			/* Set the corresponding bit in the filter. */
1698 			hash[crc >> 4] |= 1 << (15 - (crc & 15));
1699 
1700 			ETHER_NEXT_MULTI(step, enm);
1701 		}
1702 
1703 		/* Now load the hash table into the chip (if we are using it) */
1704 		for (i = 0; i < 16; i++) {
1705 			bus_space_write_4(t, h,
1706 			    GEM_MAC_HASH0 + i * (GEM_MAC_HASH1 - GEM_MAC_HASH0),
1707 			    hash[i]);
1708 		}
1709 	}
1710 
1711 	bus_space_write_4(t, h, GEM_MAC_RX_CONFIG, rxcfg);
1712 }
1713 
1714 /*
1715  * Transmit interrupt.
1716  */
1717 int
1718 gem_tint(struct gem_softc *sc, u_int32_t status)
1719 {
1720 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1721 	struct gem_sxd *sd;
1722 	u_int32_t cons, hwcons;
1723 
1724 	hwcons = status >> 19;
1725 	cons = sc->sc_tx_cons;
1726 	while (cons != hwcons) {
1727 		sd = &sc->sc_txd[cons];
1728 		if (sd->sd_mbuf != NULL) {
1729 			bus_dmamap_sync(sc->sc_dmatag, sd->sd_map, 0,
1730 			    sd->sd_map->dm_mapsize, BUS_DMASYNC_POSTWRITE);
1731 			bus_dmamap_unload(sc->sc_dmatag, sd->sd_map);
1732 			m_freem(sd->sd_mbuf);
1733 			sd->sd_mbuf = NULL;
1734 			ifp->if_opackets++;
1735 		}
1736 		sc->sc_tx_cnt--;
1737 		if (++cons == GEM_NTXDESC)
1738 			cons = 0;
1739 	}
1740 	sc->sc_tx_cons = cons;
1741 
1742 	if (sc->sc_tx_cnt < GEM_NTXDESC - 2)
1743 		ifp->if_flags &= ~IFF_OACTIVE;
1744 	if (sc->sc_tx_cnt == 0)
1745 		ifp->if_timer = 0;
1746 
1747 	gem_start(ifp);
1748 
1749 	return (1);
1750 }
1751 
1752 void
1753 gem_start(struct ifnet *ifp)
1754 {
1755 	struct gem_softc *sc = ifp->if_softc;
1756 	struct mbuf *m;
1757 	u_int64_t flags;
1758 	bus_dmamap_t map;
1759 	u_int32_t cur, frag, i;
1760 	int error;
1761 
1762 	if ((ifp->if_flags & (IFF_RUNNING | IFF_OACTIVE)) != IFF_RUNNING)
1763 		return;
1764 
1765 	while (sc->sc_txd[sc->sc_tx_prod].sd_mbuf == NULL) {
1766 		IFQ_POLL(&ifp->if_snd, m);
1767 		if (m == NULL)
1768 			break;
1769 
1770 		/*
1771 		 * Encapsulate this packet and start it going...
1772 		 * or fail...
1773 		 */
1774 
1775 		cur = frag = sc->sc_tx_prod;
1776 		map = sc->sc_txd[cur].sd_map;
1777 
1778 		error = bus_dmamap_load_mbuf(sc->sc_dmatag, map, m,
1779 		    BUS_DMA_NOWAIT);
1780 		if (error != 0 && error != EFBIG)
1781 			goto drop;
1782 		if (error != 0) {
1783 			/* Too many fragments, linearize. */
1784 			if (m_defrag(m, M_DONTWAIT))
1785 				goto drop;
1786 			error = bus_dmamap_load_mbuf(sc->sc_dmatag, map, m,
1787 			    BUS_DMA_NOWAIT);
1788 			if (error != 0)
1789 				goto drop;
1790 		}
1791 
1792 		if ((sc->sc_tx_cnt + map->dm_nsegs) > (GEM_NTXDESC - 2)) {
1793 			bus_dmamap_unload(sc->sc_dmatag, map);
1794 			ifp->if_flags |= IFF_OACTIVE;
1795 			break;
1796 		}
1797 
1798 		/* We are now committed to transmitting the packet. */
1799 		IFQ_DEQUEUE(&ifp->if_snd, m);
1800 
1801 #if NBPFILTER > 0
1802 		/*
1803 		 * If BPF is listening on this interface, let it see the
1804 		 * packet before we commit it to the wire.
1805 		 */
1806 		if (ifp->if_bpf)
1807 			bpf_mtap(ifp->if_bpf, m, BPF_DIRECTION_OUT);
1808 #endif
1809 
1810 		bus_dmamap_sync(sc->sc_dmatag, map, 0, map->dm_mapsize,
1811 		    BUS_DMASYNC_PREWRITE);
1812 
1813 		for (i = 0; i < map->dm_nsegs; i++) {
1814 			GEM_DMA_WRITE(sc, &sc->sc_txdescs[frag].gd_addr,
1815 			    map->dm_segs[i].ds_addr);
1816 			flags = map->dm_segs[i].ds_len & GEM_TD_BUFSIZE;
1817 			if (i == 0)
1818 				flags |= GEM_TD_START_OF_PACKET;
1819 			if (i == (map->dm_nsegs - 1))
1820 				flags |= GEM_TD_END_OF_PACKET;
1821 			GEM_DMA_WRITE(sc, &sc->sc_txdescs[frag].gd_flags,
1822 			    flags);
1823 			bus_dmamap_sync(sc->sc_dmatag, sc->sc_cddmamap,
1824 			    GEM_CDTXOFF(frag), sizeof(struct gem_desc),
1825 			    BUS_DMASYNC_PREWRITE);
1826 			cur = frag;
1827 			if (++frag == GEM_NTXDESC)
1828 				frag = 0;
1829 		}
1830 
1831 		sc->sc_tx_cnt += map->dm_nsegs;
1832 		sc->sc_txd[sc->sc_tx_prod].sd_map = sc->sc_txd[cur].sd_map;
1833 		sc->sc_txd[cur].sd_map = map;
1834 		sc->sc_txd[cur].sd_mbuf = m;
1835 
1836 		bus_space_write_4(sc->sc_bustag, sc->sc_h1, GEM_TX_KICK, frag);
1837 		sc->sc_tx_prod = frag;
1838 
1839 		ifp->if_timer = 5;
1840 	}
1841 
1842 	return;
1843 
1844  drop:
1845 	IFQ_DEQUEUE(&ifp->if_snd, m);
1846 	m_freem(m);
1847 	ifp->if_oerrors++;
1848 }
1849