xref: /netbsd-src/sys/dev/ic/gem.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: gem.c,v 1.60 2007/10/19 11:59:51 ad Exp $ */
2 
3 /*
4  *
5  * Copyright (C) 2001 Eduardo Horvath.
6  * All rights reserved.
7  *
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR  ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR  BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  */
31 
32 /*
33  * Driver for Sun GEM ethernet controllers.
34  */
35 
36 #include <sys/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: gem.c,v 1.60 2007/10/19 11:59:51 ad Exp $");
38 
39 #include "opt_inet.h"
40 #include "bpfilter.h"
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/callout.h>
45 #include <sys/mbuf.h>
46 #include <sys/syslog.h>
47 #include <sys/malloc.h>
48 #include <sys/kernel.h>
49 #include <sys/socket.h>
50 #include <sys/ioctl.h>
51 #include <sys/errno.h>
52 #include <sys/device.h>
53 
54 #include <machine/endian.h>
55 
56 #include <uvm/uvm_extern.h>
57 
58 #include <net/if.h>
59 #include <net/if_dl.h>
60 #include <net/if_media.h>
61 #include <net/if_ether.h>
62 
63 #ifdef INET
64 #include <netinet/in.h>
65 #include <netinet/in_systm.h>
66 #include <netinet/in_var.h>
67 #include <netinet/ip.h>
68 #include <netinet/tcp.h>
69 #include <netinet/udp.h>
70 #endif
71 
72 #if NBPFILTER > 0
73 #include <net/bpf.h>
74 #endif
75 
76 #include <sys/bus.h>
77 #include <sys/intr.h>
78 
79 #include <dev/mii/mii.h>
80 #include <dev/mii/miivar.h>
81 #include <dev/mii/mii_bitbang.h>
82 
83 #include <dev/ic/gemreg.h>
84 #include <dev/ic/gemvar.h>
85 
86 #define TRIES	10000
87 
88 static void	gem_start(struct ifnet *);
89 static void	gem_stop(struct ifnet *, int);
90 int		gem_ioctl(struct ifnet *, u_long, void *);
91 void		gem_tick(void *);
92 void		gem_watchdog(struct ifnet *);
93 void		gem_shutdown(void *);
94 int		gem_init(struct ifnet *);
95 void		gem_init_regs(struct gem_softc *sc);
96 static int	gem_ringsize(int sz);
97 static int	gem_meminit(struct gem_softc *);
98 void		gem_mifinit(struct gem_softc *);
99 static int	gem_bitwait(struct gem_softc *sc, bus_space_handle_t, int,
100 		    u_int32_t, u_int32_t);
101 void		gem_reset(struct gem_softc *);
102 int		gem_reset_rx(struct gem_softc *sc);
103 int		gem_reset_tx(struct gem_softc *sc);
104 int		gem_disable_rx(struct gem_softc *sc);
105 int		gem_disable_tx(struct gem_softc *sc);
106 static void	gem_rxdrain(struct gem_softc *sc);
107 int		gem_add_rxbuf(struct gem_softc *sc, int idx);
108 void		gem_setladrf(struct gem_softc *);
109 
110 /* MII methods & callbacks */
111 static int	gem_mii_readreg(struct device *, int, int);
112 static void	gem_mii_writereg(struct device *, int, int, int);
113 static void	gem_mii_statchg(struct device *);
114 
115 int		gem_mediachange(struct ifnet *);
116 void		gem_mediastatus(struct ifnet *, struct ifmediareq *);
117 
118 struct mbuf	*gem_get(struct gem_softc *, int, int);
119 int		gem_put(struct gem_softc *, int, struct mbuf *);
120 void		gem_read(struct gem_softc *, int, int);
121 int		gem_eint(struct gem_softc *, u_int);
122 int		gem_rint(struct gem_softc *);
123 int		gem_tint(struct gem_softc *);
124 void		gem_power(int, void *);
125 
126 #ifdef GEM_DEBUG
127 #define	DPRINTF(sc, x)	if ((sc)->sc_ethercom.ec_if.if_flags & IFF_DEBUG) \
128 				printf x
129 #else
130 #define	DPRINTF(sc, x)	/* nothing */
131 #endif
132 
133 #define ETHER_MIN_TX (ETHERMIN + sizeof(struct ether_header))
134 
135 
136 /*
137  * gem_attach:
138  *
139  *	Attach a Gem interface to the system.
140  */
141 void
142 gem_attach(sc, enaddr)
143 	struct gem_softc *sc;
144 	const uint8_t *enaddr;
145 {
146 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
147 	struct mii_data *mii = &sc->sc_mii;
148 	struct mii_softc *child;
149 	struct ifmedia_entry *ifm;
150 	int i, error;
151 	u_int32_t v;
152 	char *nullbuf;
153 
154 	/* Make sure the chip is stopped. */
155 	ifp->if_softc = sc;
156 	gem_reset(sc);
157 
158 	/*
159 	 * Allocate the control data structures, and create and load the
160 	 * DMA map for it. gem_control_data is 9216 bytes, we have space for
161 	 * the padding buffer in the bus_dmamem_alloc()'d memory.
162 	 */
163 	if ((error = bus_dmamem_alloc(sc->sc_dmatag,
164 	    sizeof(struct gem_control_data) + ETHER_MIN_TX, PAGE_SIZE,
165 	    0, &sc->sc_cdseg, 1, &sc->sc_cdnseg, 0)) != 0) {
166 		aprint_error(
167 		   "%s: unable to allocate control data, error = %d\n",
168 		    sc->sc_dev.dv_xname, error);
169 		goto fail_0;
170 	}
171 
172 /* XXX should map this in with correct endianness */
173 	if ((error = bus_dmamem_map(sc->sc_dmatag, &sc->sc_cdseg, sc->sc_cdnseg,
174 	    sizeof(struct gem_control_data), (void **)&sc->sc_control_data,
175 	    BUS_DMA_COHERENT)) != 0) {
176 		aprint_error("%s: unable to map control data, error = %d\n",
177 		    sc->sc_dev.dv_xname, error);
178 		goto fail_1;
179 	}
180 
181 	nullbuf =
182 	    (char *)sc->sc_control_data + sizeof(struct gem_control_data);
183 
184 	if ((error = bus_dmamap_create(sc->sc_dmatag,
185 	    sizeof(struct gem_control_data), 1,
186 	    sizeof(struct gem_control_data), 0, 0, &sc->sc_cddmamap)) != 0) {
187 		aprint_error("%s: unable to create control data DMA map, "
188 		    "error = %d\n", sc->sc_dev.dv_xname, error);
189 		goto fail_2;
190 	}
191 
192 	if ((error = bus_dmamap_load(sc->sc_dmatag, sc->sc_cddmamap,
193 	    sc->sc_control_data, sizeof(struct gem_control_data), NULL,
194 	    0)) != 0) {
195 		aprint_error(
196 		    "%s: unable to load control data DMA map, error = %d\n",
197 		    sc->sc_dev.dv_xname, error);
198 		goto fail_3;
199 	}
200 
201 	memset(nullbuf, 0, ETHER_MIN_TX);
202 	if ((error = bus_dmamap_create(sc->sc_dmatag,
203 	    ETHER_MIN_TX, 1, ETHER_MIN_TX, 0, 0, &sc->sc_nulldmamap)) != 0) {
204 		aprint_error("%s: unable to create padding DMA map, "
205 		    "error = %d\n", sc->sc_dev.dv_xname, error);
206 		goto fail_4;
207 	}
208 
209 	if ((error = bus_dmamap_load(sc->sc_dmatag, sc->sc_nulldmamap,
210 	    nullbuf, ETHER_MIN_TX, NULL, 0)) != 0) {
211 		aprint_error(
212 		    "%s: unable to load padding DMA map, error = %d\n",
213 		    sc->sc_dev.dv_xname, error);
214 		goto fail_5;
215 	}
216 
217 	bus_dmamap_sync(sc->sc_dmatag, sc->sc_nulldmamap, 0, ETHER_MIN_TX,
218 	    BUS_DMASYNC_PREWRITE);
219 
220 	/*
221 	 * Initialize the transmit job descriptors.
222 	 */
223 	SIMPLEQ_INIT(&sc->sc_txfreeq);
224 	SIMPLEQ_INIT(&sc->sc_txdirtyq);
225 
226 	/*
227 	 * Create the transmit buffer DMA maps.
228 	 */
229 	for (i = 0; i < GEM_TXQUEUELEN; i++) {
230 		struct gem_txsoft *txs;
231 
232 		txs = &sc->sc_txsoft[i];
233 		txs->txs_mbuf = NULL;
234 		if ((error = bus_dmamap_create(sc->sc_dmatag,
235 		    ETHER_MAX_LEN_JUMBO, GEM_NTXSEGS,
236 		    ETHER_MAX_LEN_JUMBO, 0, 0,
237 		    &txs->txs_dmamap)) != 0) {
238 			aprint_error("%s: unable to create tx DMA map %d, "
239 			    "error = %d\n", sc->sc_dev.dv_xname, i, error);
240 			goto fail_6;
241 		}
242 		SIMPLEQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
243 	}
244 
245 	/*
246 	 * Create the receive buffer DMA maps.
247 	 */
248 	for (i = 0; i < GEM_NRXDESC; i++) {
249 		if ((error = bus_dmamap_create(sc->sc_dmatag, MCLBYTES, 1,
250 		    MCLBYTES, 0, 0, &sc->sc_rxsoft[i].rxs_dmamap)) != 0) {
251 			aprint_error("%s: unable to create rx DMA map %d, "
252 			    "error = %d\n", sc->sc_dev.dv_xname, i, error);
253 			goto fail_7;
254 		}
255 		sc->sc_rxsoft[i].rxs_mbuf = NULL;
256 	}
257 
258 	/*
259 	 * From this point forward, the attachment cannot fail.  A failure
260 	 * before this point releases all resources that may have been
261 	 * allocated.
262 	 */
263 
264 	/* Announce ourselves. */
265 	aprint_normal("%s: Ethernet address %s", sc->sc_dev.dv_xname,
266 	    ether_sprintf(enaddr));
267 
268 	/* Get RX FIFO size */
269 	sc->sc_rxfifosize = 64 *
270 	    bus_space_read_4(sc->sc_bustag, sc->sc_h1, GEM_RX_FIFO_SIZE);
271 	aprint_normal(", %uKB RX fifo", sc->sc_rxfifosize / 1024);
272 
273 	/* Get TX FIFO size */
274 	v = bus_space_read_4(sc->sc_bustag, sc->sc_h1, GEM_TX_FIFO_SIZE);
275 	aprint_normal(", %uKB TX fifo\n", v / 16);
276 
277 	/* Initialize ifnet structure. */
278 	strcpy(ifp->if_xname, sc->sc_dev.dv_xname);
279 	ifp->if_softc = sc;
280 	ifp->if_flags =
281 	    IFF_BROADCAST | IFF_SIMPLEX | IFF_NOTRAILERS | IFF_MULTICAST;
282 	sc->sc_if_flags = ifp->if_flags;
283 	ifp->if_capabilities |=
284 	    IFCAP_CSUM_TCPv4_Tx | IFCAP_CSUM_TCPv4_Rx |
285 	    IFCAP_CSUM_UDPv4_Tx | IFCAP_CSUM_UDPv4_Rx;
286 	ifp->if_start = gem_start;
287 	ifp->if_ioctl = gem_ioctl;
288 	ifp->if_watchdog = gem_watchdog;
289 	ifp->if_stop = gem_stop;
290 	ifp->if_init = gem_init;
291 	IFQ_SET_READY(&ifp->if_snd);
292 
293 	/* Initialize ifmedia structures and MII info */
294 	mii->mii_ifp = ifp;
295 	mii->mii_readreg = gem_mii_readreg;
296 	mii->mii_writereg = gem_mii_writereg;
297 	mii->mii_statchg = gem_mii_statchg;
298 
299 	ifmedia_init(&mii->mii_media, IFM_IMASK, gem_mediachange, gem_mediastatus);
300 
301 	gem_mifinit(sc);
302 
303 #if defined (PMAC_G5)
304 	mii_attach(&sc->sc_dev, mii, 0xffffffff,
305 			1, MII_OFFSET_ANY, MIIF_FORCEANEG);
306 #else
307 	mii_attach(&sc->sc_dev, mii, 0xffffffff,
308 			MII_PHY_ANY, MII_OFFSET_ANY, MIIF_FORCEANEG);
309 #endif
310 
311 	child = LIST_FIRST(&mii->mii_phys);
312 	if (child == NULL) {
313 		/* No PHY attached */
314 		ifmedia_add(&sc->sc_media, IFM_ETHER|IFM_MANUAL, 0, NULL);
315 		ifmedia_set(&sc->sc_media, IFM_ETHER|IFM_MANUAL);
316 	} else {
317 		/*
318 		 * Walk along the list of attached MII devices and
319 		 * establish an `MII instance' to `phy number'
320 		 * mapping. We'll use this mapping in media change
321 		 * requests to determine which phy to use to program
322 		 * the MIF configuration register.
323 		 */
324 		for (; child != NULL; child = LIST_NEXT(child, mii_list)) {
325 			/*
326 			 * Note: we support just two PHYs: the built-in
327 			 * internal device and an external on the MII
328 			 * connector.
329 			 */
330 			if (child->mii_phy > 1 || child->mii_inst > 1) {
331 				aprint_error(
332 				    "%s: cannot accommodate MII device %s"
333 				       " at phy %d, instance %d\n",
334 				       sc->sc_dev.dv_xname,
335 				       child->mii_dev.dv_xname,
336 				       child->mii_phy, child->mii_inst);
337 				continue;
338 			}
339 
340 			sc->sc_phys[child->mii_inst] = child->mii_phy;
341 		}
342 
343 		/*
344 		 * Now select and activate the PHY we will use.
345 		 *
346 		 * The order of preference is External (MDI1),
347 		 * Internal (MDI0), Serial Link (no MII).
348 		 */
349 		if (sc->sc_phys[1]) {
350 #ifdef GEM_DEBUG
351 			aprint_debug("using external phy\n");
352 #endif
353 			sc->sc_mif_config |= GEM_MIF_CONFIG_PHY_SEL;
354 		} else {
355 #ifdef GEM_DEBUG
356 			aprint_debug("using internal phy\n");
357 #endif
358 			sc->sc_mif_config &= ~GEM_MIF_CONFIG_PHY_SEL;
359 		}
360 		bus_space_write_4(sc->sc_bustag, sc->sc_h1, GEM_MIF_CONFIG,
361 			sc->sc_mif_config);
362 
363 		/*
364 		 * XXX - we can really do the following ONLY if the
365 		 * phy indeed has the auto negotiation capability!!
366 		 */
367 		ifmedia_set(&sc->sc_media, IFM_ETHER|IFM_AUTO);
368 	}
369 
370 	/*
371 	 * If we support GigE media, we support jumbo frames too.
372 	 * Unless we are Apple.
373 	 */
374 	TAILQ_FOREACH(ifm, &sc->sc_media.ifm_list, ifm_list) {
375 		if (IFM_SUBTYPE(ifm->ifm_media) == IFM_1000_T ||
376 		    IFM_SUBTYPE(ifm->ifm_media) == IFM_1000_SX ||
377 		    IFM_SUBTYPE(ifm->ifm_media) == IFM_1000_LX ||
378 		    IFM_SUBTYPE(ifm->ifm_media) == IFM_1000_CX) {
379 			if (sc->sc_variant != GEM_APPLE_GMAC)
380 				sc->sc_ethercom.ec_capabilities
381 				    |= ETHERCAP_JUMBO_MTU;
382 
383 			sc->sc_flags |= GEM_GIGABIT;
384 			break;
385 		}
386 	}
387 
388 	/* claim 802.1q capability */
389 	sc->sc_ethercom.ec_capabilities |= ETHERCAP_VLAN_MTU;
390 
391 	/* Attach the interface. */
392 	if_attach(ifp);
393 	ether_ifattach(ifp, enaddr);
394 
395 	sc->sc_sh = shutdownhook_establish(gem_shutdown, sc);
396 	if (sc->sc_sh == NULL)
397 		panic("gem_config: can't establish shutdownhook");
398 
399 #if NRND > 0
400 	rnd_attach_source(&sc->rnd_source, sc->sc_dev.dv_xname,
401 			  RND_TYPE_NET, 0);
402 #endif
403 
404 	evcnt_attach_dynamic(&sc->sc_ev_intr, EVCNT_TYPE_INTR,
405 	    NULL, sc->sc_dev.dv_xname, "interrupts");
406 #ifdef GEM_COUNTERS
407 	evcnt_attach_dynamic(&sc->sc_ev_txint, EVCNT_TYPE_INTR,
408 	    &sc->sc_ev_intr, sc->sc_dev.dv_xname, "tx interrupts");
409 	evcnt_attach_dynamic(&sc->sc_ev_rxint, EVCNT_TYPE_INTR,
410 	    &sc->sc_ev_intr, sc->sc_dev.dv_xname, "rx interrupts");
411 	evcnt_attach_dynamic(&sc->sc_ev_rxfull, EVCNT_TYPE_INTR,
412 	    &sc->sc_ev_rxint, sc->sc_dev.dv_xname, "rx ring full");
413 	evcnt_attach_dynamic(&sc->sc_ev_rxnobuf, EVCNT_TYPE_INTR,
414 	    &sc->sc_ev_rxint, sc->sc_dev.dv_xname, "rx malloc failure");
415 	evcnt_attach_dynamic(&sc->sc_ev_rxhist[0], EVCNT_TYPE_INTR,
416 	    &sc->sc_ev_rxint, sc->sc_dev.dv_xname, "rx 0desc");
417 	evcnt_attach_dynamic(&sc->sc_ev_rxhist[1], EVCNT_TYPE_INTR,
418 	    &sc->sc_ev_rxint, sc->sc_dev.dv_xname, "rx 1desc");
419 	evcnt_attach_dynamic(&sc->sc_ev_rxhist[2], EVCNT_TYPE_INTR,
420 	    &sc->sc_ev_rxint, sc->sc_dev.dv_xname, "rx 2desc");
421 	evcnt_attach_dynamic(&sc->sc_ev_rxhist[3], EVCNT_TYPE_INTR,
422 	    &sc->sc_ev_rxint, sc->sc_dev.dv_xname, "rx 3desc");
423 	evcnt_attach_dynamic(&sc->sc_ev_rxhist[4], EVCNT_TYPE_INTR,
424 	    &sc->sc_ev_rxint, sc->sc_dev.dv_xname, "rx >3desc");
425 	evcnt_attach_dynamic(&sc->sc_ev_rxhist[5], EVCNT_TYPE_INTR,
426 	    &sc->sc_ev_rxint, sc->sc_dev.dv_xname, "rx >7desc");
427 	evcnt_attach_dynamic(&sc->sc_ev_rxhist[6], EVCNT_TYPE_INTR,
428 	    &sc->sc_ev_rxint, sc->sc_dev.dv_xname, "rx >15desc");
429 	evcnt_attach_dynamic(&sc->sc_ev_rxhist[7], EVCNT_TYPE_INTR,
430 	    &sc->sc_ev_rxint, sc->sc_dev.dv_xname, "rx >31desc");
431 	evcnt_attach_dynamic(&sc->sc_ev_rxhist[8], EVCNT_TYPE_INTR,
432 	    &sc->sc_ev_rxint, sc->sc_dev.dv_xname, "rx >63desc");
433 #endif
434 
435 #if notyet
436 	/*
437 	 * Add a suspend hook to make sure we come back up after a
438 	 * resume.
439 	 */
440 	sc->sc_powerhook = powerhook_establish(sc->sc_dev.dv_xname,
441 	    gem_power, sc);
442 	if (sc->sc_powerhook == NULL)
443 		aprint_error("%s: WARNING: unable to establish power hook\n",
444 		    sc->sc_dev.dv_xname);
445 #endif
446 
447 	callout_init(&sc->sc_tick_ch, 0);
448 	return;
449 
450 	/*
451 	 * Free any resources we've allocated during the failed attach
452 	 * attempt.  Do this in reverse order and fall through.
453 	 */
454  fail_7:
455 	for (i = 0; i < GEM_NRXDESC; i++) {
456 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
457 			bus_dmamap_destroy(sc->sc_dmatag,
458 			    sc->sc_rxsoft[i].rxs_dmamap);
459 	}
460  fail_6:
461 	for (i = 0; i < GEM_TXQUEUELEN; i++) {
462 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
463 			bus_dmamap_destroy(sc->sc_dmatag,
464 			    sc->sc_txsoft[i].txs_dmamap);
465 	}
466 	bus_dmamap_unload(sc->sc_dmatag, sc->sc_cddmamap);
467  fail_5:
468 	bus_dmamap_destroy(sc->sc_dmatag, sc->sc_nulldmamap);
469  fail_4:
470 	bus_dmamem_unmap(sc->sc_dmatag, (void *)nullbuf, ETHER_MIN_TX);
471  fail_3:
472 	bus_dmamap_destroy(sc->sc_dmatag, sc->sc_cddmamap);
473  fail_2:
474 	bus_dmamem_unmap(sc->sc_dmatag, (void *)sc->sc_control_data,
475 	    sizeof(struct gem_control_data));
476  fail_1:
477 	bus_dmamem_free(sc->sc_dmatag, &sc->sc_cdseg, sc->sc_cdnseg);
478  fail_0:
479 	return;
480 }
481 
482 
483 void
484 gem_tick(arg)
485 	void *arg;
486 {
487 	struct gem_softc *sc = arg;
488 	int s;
489 
490 	s = splnet();
491 	mii_tick(&sc->sc_mii);
492 	splx(s);
493 
494 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
495 
496 }
497 
498 static int
499 gem_bitwait(sc, h, r, clr, set)
500 	struct gem_softc *sc;
501 	bus_space_handle_t h;
502 	int r;
503 	u_int32_t clr;
504 	u_int32_t set;
505 {
506 	int i;
507 	u_int32_t reg;
508 
509 	for (i = TRIES; i--; DELAY(100)) {
510 		reg = bus_space_read_4(sc->sc_bustag, h, r);
511 		if ((reg & clr) == 0 && (reg & set) == set)
512 			return (1);
513 	}
514 	return (0);
515 }
516 
517 void
518 gem_reset(sc)
519 	struct gem_softc *sc;
520 {
521 	bus_space_tag_t t = sc->sc_bustag;
522 	bus_space_handle_t h = sc->sc_h2;
523 	int s;
524 
525 	s = splnet();
526 	DPRINTF(sc, ("%s: gem_reset\n", sc->sc_dev.dv_xname));
527 	gem_reset_rx(sc);
528 	gem_reset_tx(sc);
529 
530 	/* Do a full reset */
531 	bus_space_write_4(t, h, GEM_RESET, GEM_RESET_RX|GEM_RESET_TX);
532 	if (!gem_bitwait(sc, h, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX, 0))
533 		printf("%s: cannot reset device\n", sc->sc_dev.dv_xname);
534 	splx(s);
535 }
536 
537 
538 /*
539  * gem_rxdrain:
540  *
541  *	Drain the receive queue.
542  */
543 static void
544 gem_rxdrain(struct gem_softc *sc)
545 {
546 	struct gem_rxsoft *rxs;
547 	int i;
548 
549 	for (i = 0; i < GEM_NRXDESC; i++) {
550 		rxs = &sc->sc_rxsoft[i];
551 		if (rxs->rxs_mbuf != NULL) {
552 			bus_dmamap_sync(sc->sc_dmatag, rxs->rxs_dmamap, 0,
553 			    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);
554 			bus_dmamap_unload(sc->sc_dmatag, rxs->rxs_dmamap);
555 			m_freem(rxs->rxs_mbuf);
556 			rxs->rxs_mbuf = NULL;
557 		}
558 	}
559 }
560 
561 /*
562  * Reset the whole thing.
563  */
564 static void
565 gem_stop(struct ifnet *ifp, int disable)
566 {
567 	struct gem_softc *sc = (struct gem_softc *)ifp->if_softc;
568 	struct gem_txsoft *txs;
569 
570 	DPRINTF(sc, ("%s: gem_stop\n", sc->sc_dev.dv_xname));
571 
572 	callout_stop(&sc->sc_tick_ch);
573 	mii_down(&sc->sc_mii);
574 
575 	/* XXX - Should we reset these instead? */
576 	gem_disable_rx(sc);
577 	gem_disable_tx(sc);
578 
579 	/*
580 	 * Release any queued transmit buffers.
581 	 */
582 	while ((txs = SIMPLEQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
583 		SIMPLEQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
584 		if (txs->txs_mbuf != NULL) {
585 			bus_dmamap_sync(sc->sc_dmatag, txs->txs_dmamap, 0,
586 			    txs->txs_dmamap->dm_mapsize, BUS_DMASYNC_POSTWRITE);
587 			bus_dmamap_unload(sc->sc_dmatag, txs->txs_dmamap);
588 			m_freem(txs->txs_mbuf);
589 			txs->txs_mbuf = NULL;
590 		}
591 		SIMPLEQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
592 	}
593 
594 	if (disable) {
595 		gem_rxdrain(sc);
596 	}
597 
598 	/*
599 	 * Mark the interface down and cancel the watchdog timer.
600 	 */
601 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
602 	sc->sc_if_flags = ifp->if_flags;
603 	ifp->if_timer = 0;
604 }
605 
606 
607 /*
608  * Reset the receiver
609  */
610 int
611 gem_reset_rx(struct gem_softc *sc)
612 {
613 	bus_space_tag_t t = sc->sc_bustag;
614 	bus_space_handle_t h = sc->sc_h1, h2 = sc->sc_h2;
615 
616 	/*
617 	 * Resetting while DMA is in progress can cause a bus hang, so we
618 	 * disable DMA first.
619 	 */
620 	gem_disable_rx(sc);
621 	bus_space_write_4(t, h, GEM_RX_CONFIG, 0);
622 	/* Wait till it finishes */
623 	if (!gem_bitwait(sc, h, GEM_RX_CONFIG, 1, 0))
624 		printf("%s: cannot disable read dma\n", sc->sc_dev.dv_xname);
625 	/* Wait 5ms extra. */
626 	delay(5000);
627 
628 	/* Finally, reset the ERX */
629 	bus_space_write_4(t, h2, GEM_RESET, GEM_RESET_RX);
630 	/* Wait till it finishes */
631 	if (!gem_bitwait(sc, h2, GEM_RESET, GEM_RESET_RX, 0)) {
632 		printf("%s: cannot reset receiver\n", sc->sc_dev.dv_xname);
633 		return (1);
634 	}
635 	return (0);
636 }
637 
638 
639 /*
640  * Reset the transmitter
641  */
642 int
643 gem_reset_tx(struct gem_softc *sc)
644 {
645 	bus_space_tag_t t = sc->sc_bustag;
646 	bus_space_handle_t h = sc->sc_h1, h2 = sc->sc_h2;
647 
648 	/*
649 	 * Resetting while DMA is in progress can cause a bus hang, so we
650 	 * disable DMA first.
651 	 */
652 	gem_disable_tx(sc);
653 	bus_space_write_4(t, h, GEM_TX_CONFIG, 0);
654 	/* Wait till it finishes */
655 	if (!gem_bitwait(sc, h, GEM_TX_CONFIG, 1, 0))
656 		printf("%s: cannot disable read dma\n", sc->sc_dev.dv_xname);
657 	/* Wait 5ms extra. */
658 	delay(5000);
659 
660 	/* Finally, reset the ETX */
661 	bus_space_write_4(t, h2, GEM_RESET, GEM_RESET_TX);
662 	/* Wait till it finishes */
663 	if (!gem_bitwait(sc, h2, GEM_RESET, GEM_RESET_TX, 0)) {
664 		printf("%s: cannot reset receiver\n",
665 			sc->sc_dev.dv_xname);
666 		return (1);
667 	}
668 	return (0);
669 }
670 
671 /*
672  * disable receiver.
673  */
674 int
675 gem_disable_rx(struct gem_softc *sc)
676 {
677 	bus_space_tag_t t = sc->sc_bustag;
678 	bus_space_handle_t h = sc->sc_h1;
679 	u_int32_t cfg;
680 
681 	/* Flip the enable bit */
682 	cfg = bus_space_read_4(t, h, GEM_MAC_RX_CONFIG);
683 	cfg &= ~GEM_MAC_RX_ENABLE;
684 	bus_space_write_4(t, h, GEM_MAC_RX_CONFIG, cfg);
685 
686 	/* Wait for it to finish */
687 	return (gem_bitwait(sc, h, GEM_MAC_RX_CONFIG, GEM_MAC_RX_ENABLE, 0));
688 }
689 
690 /*
691  * disable transmitter.
692  */
693 int
694 gem_disable_tx(struct gem_softc *sc)
695 {
696 	bus_space_tag_t t = sc->sc_bustag;
697 	bus_space_handle_t h = sc->sc_h1;
698 	u_int32_t cfg;
699 
700 	/* Flip the enable bit */
701 	cfg = bus_space_read_4(t, h, GEM_MAC_TX_CONFIG);
702 	cfg &= ~GEM_MAC_TX_ENABLE;
703 	bus_space_write_4(t, h, GEM_MAC_TX_CONFIG, cfg);
704 
705 	/* Wait for it to finish */
706 	return (gem_bitwait(sc, h, GEM_MAC_TX_CONFIG, GEM_MAC_TX_ENABLE, 0));
707 }
708 
709 /*
710  * Initialize interface.
711  */
712 int
713 gem_meminit(struct gem_softc *sc)
714 {
715 	struct gem_rxsoft *rxs;
716 	int i, error;
717 
718 	/*
719 	 * Initialize the transmit descriptor ring.
720 	 */
721 	memset((void *)sc->sc_txdescs, 0, sizeof(sc->sc_txdescs));
722 	for (i = 0; i < GEM_NTXDESC; i++) {
723 		sc->sc_txdescs[i].gd_flags = 0;
724 		sc->sc_txdescs[i].gd_addr = 0;
725 	}
726 	GEM_CDTXSYNC(sc, 0, GEM_NTXDESC,
727 	    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
728 	sc->sc_txfree = GEM_NTXDESC-1;
729 	sc->sc_txnext = 0;
730 	sc->sc_txwin = 0;
731 
732 	/*
733 	 * Initialize the receive descriptor and receive job
734 	 * descriptor rings.
735 	 */
736 	for (i = 0; i < GEM_NRXDESC; i++) {
737 		rxs = &sc->sc_rxsoft[i];
738 		if (rxs->rxs_mbuf == NULL) {
739 			if ((error = gem_add_rxbuf(sc, i)) != 0) {
740 				printf("%s: unable to allocate or map rx "
741 				    "buffer %d, error = %d\n",
742 				    sc->sc_dev.dv_xname, i, error);
743 				/*
744 				 * XXX Should attempt to run with fewer receive
745 				 * XXX buffers instead of just failing.
746 				 */
747 				gem_rxdrain(sc);
748 				return (1);
749 			}
750 		} else
751 			GEM_INIT_RXDESC(sc, i);
752 	}
753 	sc->sc_rxptr = 0;
754 
755 	return (0);
756 }
757 
758 static int
759 gem_ringsize(int sz)
760 {
761 	switch (sz) {
762 	case 32:
763 		return GEM_RING_SZ_32;
764 	case 64:
765 		return GEM_RING_SZ_64;
766 	case 128:
767 		return GEM_RING_SZ_128;
768 	case 256:
769 		return GEM_RING_SZ_256;
770 	case 512:
771 		return GEM_RING_SZ_512;
772 	case 1024:
773 		return GEM_RING_SZ_1024;
774 	case 2048:
775 		return GEM_RING_SZ_2048;
776 	case 4096:
777 		return GEM_RING_SZ_4096;
778 	case 8192:
779 		return GEM_RING_SZ_8192;
780 	default:
781 		printf("gem: invalid Receive Descriptor ring size %d\n", sz);
782 		return GEM_RING_SZ_32;
783 	}
784 }
785 
786 /*
787  * Initialization of interface; set up initialization block
788  * and transmit/receive descriptor rings.
789  */
790 int
791 gem_init(struct ifnet *ifp)
792 {
793 	struct gem_softc *sc = (struct gem_softc *)ifp->if_softc;
794 	bus_space_tag_t t = sc->sc_bustag;
795 	bus_space_handle_t h = sc->sc_h1;
796 	int s;
797 	u_int max_frame_size;
798 	u_int32_t v;
799 
800 	s = splnet();
801 
802 	DPRINTF(sc, ("%s: gem_init: calling stop\n", sc->sc_dev.dv_xname));
803 	/*
804 	 * Initialization sequence. The numbered steps below correspond
805 	 * to the sequence outlined in section 6.3.5.1 in the Ethernet
806 	 * Channel Engine manual (part of the PCIO manual).
807 	 * See also the STP2002-STQ document from Sun Microsystems.
808 	 */
809 
810 	/* step 1 & 2. Reset the Ethernet Channel */
811 	gem_stop(ifp, 0);
812 	gem_reset(sc);
813 	DPRINTF(sc, ("%s: gem_init: restarting\n", sc->sc_dev.dv_xname));
814 
815 	/* Re-initialize the MIF */
816 	gem_mifinit(sc);
817 
818 	/* Call MI reset function if any */
819 	if (sc->sc_hwreset)
820 		(*sc->sc_hwreset)(sc);
821 
822 	/* step 3. Setup data structures in host memory */
823 	gem_meminit(sc);
824 
825 	/* step 4. TX MAC registers & counters */
826 	gem_init_regs(sc);
827 	max_frame_size = max(sc->sc_ethercom.ec_if.if_mtu, ETHERMTU);
828 	max_frame_size += ETHER_HDR_LEN + ETHER_CRC_LEN;
829 	if (sc->sc_ethercom.ec_capenable & ETHERCAP_VLAN_MTU)
830 		max_frame_size += ETHER_VLAN_ENCAP_LEN;
831 	bus_space_write_4(t, h, GEM_MAC_MAC_MAX_FRAME,
832 	    max_frame_size|/* burst size */(0x2000<<16));
833 
834 	/* step 5. RX MAC registers & counters */
835 	gem_setladrf(sc);
836 
837 	/* step 6 & 7. Program Descriptor Ring Base Addresses */
838 	/* NOTE: we use only 32-bit DMA addresses here. */
839 	bus_space_write_4(t, h, GEM_TX_RING_PTR_HI, 0);
840 	bus_space_write_4(t, h, GEM_TX_RING_PTR_LO, GEM_CDTXADDR(sc, 0));
841 
842 	bus_space_write_4(t, h, GEM_RX_RING_PTR_HI, 0);
843 	bus_space_write_4(t, h, GEM_RX_RING_PTR_LO, GEM_CDRXADDR(sc, 0));
844 
845 	/* step 8. Global Configuration & Interrupt Mask */
846 	bus_space_write_4(t, h, GEM_INTMASK,
847 		      ~(GEM_INTR_TX_INTME|
848 			GEM_INTR_TX_EMPTY|
849 			GEM_INTR_RX_DONE|GEM_INTR_RX_NOBUF|
850 			GEM_INTR_RX_TAG_ERR|GEM_INTR_PCS|
851 			GEM_INTR_MAC_CONTROL|GEM_INTR_MIF|
852 			GEM_INTR_BERR));
853 	bus_space_write_4(t, h, GEM_MAC_RX_MASK,
854 			GEM_MAC_RX_DONE|GEM_MAC_RX_FRAME_CNT);
855 	bus_space_write_4(t, h, GEM_MAC_TX_MASK, 0xffff); /* XXXX */
856 	bus_space_write_4(t, h, GEM_MAC_CONTROL_MASK, 0); /* XXXX */
857 
858 	/* step 9. ETX Configuration: use mostly default values */
859 
860 	/* Enable DMA */
861 	v = gem_ringsize(GEM_NTXDESC /*XXX*/);
862 	bus_space_write_4(t, h, GEM_TX_CONFIG,
863 		v|GEM_TX_CONFIG_TXDMA_EN|
864 		((0x400<<10)&GEM_TX_CONFIG_TXFIFO_TH));
865 	bus_space_write_4(t, h, GEM_TX_KICK, sc->sc_txnext);
866 
867 	/* step 10. ERX Configuration */
868 
869 	/* Encode Receive Descriptor ring size: four possible values */
870 	v = gem_ringsize(GEM_NRXDESC /*XXX*/);
871 
872 	/* Set receive h/w checksum offset */
873 #ifdef INET
874 	v |= (ETHER_HDR_LEN + sizeof(struct ip) +
875 	      ((sc->sc_ethercom.ec_capenable & ETHERCAP_VLAN_MTU) ?
876 	        ETHER_VLAN_ENCAP_LEN : 0)) << GEM_RX_CONFIG_CXM_START_SHFT;
877 #endif
878 
879 	/* Enable DMA */
880 	bus_space_write_4(t, h, GEM_RX_CONFIG,
881 		v|(GEM_THRSH_1024<<GEM_RX_CONFIG_FIFO_THRS_SHIFT)|
882 		(2<<GEM_RX_CONFIG_FBOFF_SHFT)|GEM_RX_CONFIG_RXDMA_EN);
883 
884 	/*
885 	 * The following value is for an OFF Threshold of about 3/4 full
886 	 * and an ON Threshold of 1/4 full.
887 	 */
888 	bus_space_write_4(t, h, GEM_RX_PAUSE_THRESH,
889 	     (3 * sc->sc_rxfifosize / 256) |
890 	     (   (sc->sc_rxfifosize / 256) << 12));
891 	bus_space_write_4(t, h, GEM_RX_BLANKING, (6<<12)|6);
892 
893 	/* step 11. Configure Media */
894 	mii_mediachg(&sc->sc_mii);
895 
896 /* XXXX Serial link needs a whole different setup. */
897 
898 
899 	/* step 12. RX_MAC Configuration Register */
900 	v = bus_space_read_4(t, h, GEM_MAC_RX_CONFIG);
901 	v |= GEM_MAC_RX_ENABLE | GEM_MAC_RX_STRIP_CRC;
902 	bus_space_write_4(t, h, GEM_MAC_RX_CONFIG, v);
903 
904 	/* step 14. Issue Transmit Pending command */
905 
906 	/* Call MI initialization function if any */
907 	if (sc->sc_hwinit)
908 		(*sc->sc_hwinit)(sc);
909 
910 
911 	/* step 15.  Give the reciever a swift kick */
912 	bus_space_write_4(t, h, GEM_RX_KICK, GEM_NRXDESC-4);
913 
914 	/* Start the one second timer. */
915 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
916 
917 	ifp->if_flags |= IFF_RUNNING;
918 	ifp->if_flags &= ~IFF_OACTIVE;
919 	ifp->if_timer = 0;
920 	sc->sc_if_flags = ifp->if_flags;
921 	splx(s);
922 
923 	return (0);
924 }
925 
926 void
927 gem_init_regs(struct gem_softc *sc)
928 {
929 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
930 	bus_space_tag_t t = sc->sc_bustag;
931 	bus_space_handle_t h = sc->sc_h1;
932 	const u_char *laddr = CLLADDR(ifp->if_sadl);
933 	u_int32_t v;
934 
935 	/* These regs are not cleared on reset */
936 	if (!sc->sc_inited) {
937 
938 		/* Wooo.  Magic values. */
939 		bus_space_write_4(t, h, GEM_MAC_IPG0, 0);
940 		bus_space_write_4(t, h, GEM_MAC_IPG1, 8);
941 		bus_space_write_4(t, h, GEM_MAC_IPG2, 4);
942 
943 		bus_space_write_4(t, h, GEM_MAC_MAC_MIN_FRAME, ETHER_MIN_LEN);
944 		/* Max frame and max burst size */
945 		bus_space_write_4(t, h, GEM_MAC_MAC_MAX_FRAME,
946 		     ETHER_MAX_LEN | (0x2000<<16));
947 
948 		bus_space_write_4(t, h, GEM_MAC_PREAMBLE_LEN, 0x7);
949 		bus_space_write_4(t, h, GEM_MAC_JAM_SIZE, 0x4);
950 		bus_space_write_4(t, h, GEM_MAC_ATTEMPT_LIMIT, 0x10);
951 		/* Dunno.... */
952 		bus_space_write_4(t, h, GEM_MAC_CONTROL_TYPE, 0x8088);
953 		bus_space_write_4(t, h, GEM_MAC_RANDOM_SEED,
954 		    ((laddr[5]<<8)|laddr[4])&0x3ff);
955 
956 		/* Secondary MAC addr set to 0:0:0:0:0:0 */
957 		bus_space_write_4(t, h, GEM_MAC_ADDR3, 0);
958 		bus_space_write_4(t, h, GEM_MAC_ADDR4, 0);
959 		bus_space_write_4(t, h, GEM_MAC_ADDR5, 0);
960 
961 		/* MAC control addr set to 01:80:c2:00:00:01 */
962 		bus_space_write_4(t, h, GEM_MAC_ADDR6, 0x0001);
963 		bus_space_write_4(t, h, GEM_MAC_ADDR7, 0xc200);
964 		bus_space_write_4(t, h, GEM_MAC_ADDR8, 0x0180);
965 
966 		/* MAC filter addr set to 0:0:0:0:0:0 */
967 		bus_space_write_4(t, h, GEM_MAC_ADDR_FILTER0, 0);
968 		bus_space_write_4(t, h, GEM_MAC_ADDR_FILTER1, 0);
969 		bus_space_write_4(t, h, GEM_MAC_ADDR_FILTER2, 0);
970 
971 		bus_space_write_4(t, h, GEM_MAC_ADR_FLT_MASK1_2, 0);
972 		bus_space_write_4(t, h, GEM_MAC_ADR_FLT_MASK0, 0);
973 
974 		sc->sc_inited = 1;
975 	}
976 
977 	/* Counters need to be zeroed */
978 	bus_space_write_4(t, h, GEM_MAC_NORM_COLL_CNT, 0);
979 	bus_space_write_4(t, h, GEM_MAC_FIRST_COLL_CNT, 0);
980 	bus_space_write_4(t, h, GEM_MAC_EXCESS_COLL_CNT, 0);
981 	bus_space_write_4(t, h, GEM_MAC_LATE_COLL_CNT, 0);
982 	bus_space_write_4(t, h, GEM_MAC_DEFER_TMR_CNT, 0);
983 	bus_space_write_4(t, h, GEM_MAC_PEAK_ATTEMPTS, 0);
984 	bus_space_write_4(t, h, GEM_MAC_RX_FRAME_COUNT, 0);
985 	bus_space_write_4(t, h, GEM_MAC_RX_LEN_ERR_CNT, 0);
986 	bus_space_write_4(t, h, GEM_MAC_RX_ALIGN_ERR, 0);
987 	bus_space_write_4(t, h, GEM_MAC_RX_CRC_ERR_CNT, 0);
988 	bus_space_write_4(t, h, GEM_MAC_RX_CODE_VIOL, 0);
989 
990 	/* Un-pause stuff */
991 #if 0
992 	bus_space_write_4(t, h, GEM_MAC_SEND_PAUSE_CMD, 0x1BF0);
993 #else
994 	bus_space_write_4(t, h, GEM_MAC_SEND_PAUSE_CMD, 0);
995 #endif
996 
997 	/*
998 	 * Set the station address.
999 	 */
1000 	bus_space_write_4(t, h, GEM_MAC_ADDR0, (laddr[4]<<8)|laddr[5]);
1001 	bus_space_write_4(t, h, GEM_MAC_ADDR1, (laddr[2]<<8)|laddr[3]);
1002 	bus_space_write_4(t, h, GEM_MAC_ADDR2, (laddr[0]<<8)|laddr[1]);
1003 
1004 #if 0
1005 	if (sc->sc_variant != APPLE_GMAC)
1006 		return;
1007 #endif
1008 
1009 	/*
1010 	 * Enable MII outputs.  Enable GMII if there is a gigabit PHY.
1011 	 */
1012 	sc->sc_mif_config = bus_space_read_4(t, h, GEM_MIF_CONFIG);
1013 	v = GEM_MAC_XIF_TX_MII_ENA;
1014 	if (sc->sc_mif_config & GEM_MIF_CONFIG_MDI1) {
1015 		v |= GEM_MAC_XIF_FDPLX_LED;
1016 		if (sc->sc_flags & GEM_GIGABIT)
1017 			v |= GEM_MAC_XIF_GMII_MODE;
1018 	}
1019 	bus_space_write_4(t, h, GEM_MAC_XIF_CONFIG, v);
1020 }
1021 
1022 static void
1023 gem_start(ifp)
1024 	struct ifnet *ifp;
1025 {
1026 	struct gem_softc *sc = (struct gem_softc *)ifp->if_softc;
1027 	struct mbuf *m0, *m;
1028 	struct gem_txsoft *txs, *last_txs;
1029 	bus_dmamap_t dmamap;
1030 	int error, firsttx, nexttx = -1, lasttx = -1, ofree, seg;
1031 	uint64_t flags = 0;
1032 
1033 	if ((ifp->if_flags & (IFF_RUNNING | IFF_OACTIVE)) != IFF_RUNNING)
1034 		return;
1035 
1036 	/*
1037 	 * Remember the previous number of free descriptors and
1038 	 * the first descriptor we'll use.
1039 	 */
1040 	ofree = sc->sc_txfree;
1041 	firsttx = sc->sc_txnext;
1042 
1043 	DPRINTF(sc, ("%s: gem_start: txfree %d, txnext %d\n",
1044 	    sc->sc_dev.dv_xname, ofree, firsttx));
1045 
1046 	/*
1047 	 * Loop through the send queue, setting up transmit descriptors
1048 	 * until we drain the queue, or use up all available transmit
1049 	 * descriptors.
1050 	 */
1051 	while ((txs = SIMPLEQ_FIRST(&sc->sc_txfreeq)) != NULL &&
1052 	       sc->sc_txfree != 0) {
1053 		/*
1054 		 * Grab a packet off the queue.
1055 		 */
1056 		IFQ_POLL(&ifp->if_snd, m0);
1057 		if (m0 == NULL)
1058 			break;
1059 		m = NULL;
1060 
1061 		dmamap = txs->txs_dmamap;
1062 
1063 		/*
1064 		 * Load the DMA map.  If this fails, the packet either
1065 		 * didn't fit in the alloted number of segments, or we were
1066 		 * short on resources.  In this case, we'll copy and try
1067 		 * again.
1068 		 */
1069 		if (bus_dmamap_load_mbuf(sc->sc_dmatag, dmamap, m0,
1070 		      BUS_DMA_WRITE|BUS_DMA_NOWAIT) != 0 ||
1071 		      (m0->m_pkthdr.len < ETHER_MIN_TX &&
1072 		       dmamap->dm_nsegs == GEM_NTXSEGS)) {
1073 			if (m0->m_pkthdr.len > MCLBYTES) {
1074 				printf("%s: unable to allocate jumbo Tx "
1075 				    "cluster\n", sc->sc_dev.dv_xname);
1076 				IFQ_DEQUEUE(&ifp->if_snd, m0);
1077 				m_freem(m0);
1078 				continue;
1079 			}
1080 			MGETHDR(m, M_DONTWAIT, MT_DATA);
1081 			if (m == NULL) {
1082 				printf("%s: unable to allocate Tx mbuf\n",
1083 				    sc->sc_dev.dv_xname);
1084 				break;
1085 			}
1086 			MCLAIM(m, &sc->sc_ethercom.ec_tx_mowner);
1087 			if (m0->m_pkthdr.len > MHLEN) {
1088 				MCLGET(m, M_DONTWAIT);
1089 				if ((m->m_flags & M_EXT) == 0) {
1090 					printf("%s: unable to allocate Tx "
1091 					    "cluster\n", sc->sc_dev.dv_xname);
1092 					m_freem(m);
1093 					break;
1094 				}
1095 			}
1096 			m_copydata(m0, 0, m0->m_pkthdr.len, mtod(m, void *));
1097 			m->m_pkthdr.len = m->m_len = m0->m_pkthdr.len;
1098 			error = bus_dmamap_load_mbuf(sc->sc_dmatag, dmamap,
1099 			    m, BUS_DMA_WRITE|BUS_DMA_NOWAIT);
1100 			if (error) {
1101 				printf("%s: unable to load Tx buffer, "
1102 				    "error = %d\n", sc->sc_dev.dv_xname, error);
1103 				break;
1104 			}
1105 		}
1106 
1107 		/*
1108 		 * Ensure we have enough descriptors free to describe
1109 		 * the packet.
1110 		 */
1111 		if (dmamap->dm_nsegs > ((m0->m_pkthdr.len < ETHER_MIN_TX) ?
1112 		     (sc->sc_txfree - 1) : sc->sc_txfree)) {
1113 			/*
1114 			 * Not enough free descriptors to transmit this
1115 			 * packet.  We haven't committed to anything yet,
1116 			 * so just unload the DMA map, put the packet
1117 			 * back on the queue, and punt.  Notify the upper
1118 			 * layer that there are no more slots left.
1119 			 *
1120 			 * XXX We could allocate an mbuf and copy, but
1121 			 * XXX it is worth it?
1122 			 */
1123 			ifp->if_flags |= IFF_OACTIVE;
1124 			sc->sc_if_flags = ifp->if_flags;
1125 			bus_dmamap_unload(sc->sc_dmatag, dmamap);
1126 			if (m != NULL)
1127 				m_freem(m);
1128 			break;
1129 		}
1130 
1131 		IFQ_DEQUEUE(&ifp->if_snd, m0);
1132 		if (m != NULL) {
1133 			m_freem(m0);
1134 			m0 = m;
1135 		}
1136 
1137 		/*
1138 		 * WE ARE NOW COMMITTED TO TRANSMITTING THE PACKET.
1139 		 */
1140 
1141 		/* Sync the DMA map. */
1142 		bus_dmamap_sync(sc->sc_dmatag, dmamap, 0, dmamap->dm_mapsize,
1143 		    BUS_DMASYNC_PREWRITE);
1144 
1145 		/*
1146 		 * Initialize the transmit descriptors.
1147 		 */
1148 		for (nexttx = sc->sc_txnext, seg = 0;
1149 		     seg < dmamap->dm_nsegs;
1150 		     seg++, nexttx = GEM_NEXTTX(nexttx)) {
1151 
1152 			/*
1153 			 * If this is the first descriptor we're
1154 			 * enqueueing, set the start of packet flag,
1155 			 * and the checksum stuff if we want the hardware
1156 			 * to do it.
1157 			 */
1158 			sc->sc_txdescs[nexttx].gd_addr =
1159 			    GEM_DMA_WRITE(sc, dmamap->dm_segs[seg].ds_addr);
1160 			flags = dmamap->dm_segs[seg].ds_len & GEM_TD_BUFSIZE;
1161 			if (nexttx == firsttx) {
1162 				flags |= GEM_TD_START_OF_PACKET;
1163 				if (++sc->sc_txwin > GEM_NTXSEGS * 2 / 3) {
1164 					sc->sc_txwin = 0;
1165 					flags |= GEM_TD_INTERRUPT_ME;
1166 				}
1167 
1168 #ifdef INET
1169 				/* h/w checksum */
1170 				if (ifp->if_csum_flags_tx & (M_CSUM_TCPv4 |
1171 				    M_CSUM_UDPv4) && m0->m_pkthdr.csum_flags &
1172 				    (M_CSUM_TCPv4|M_CSUM_UDPv4)) {
1173 					struct ether_header *eh;
1174 					uint16_t offset, start;
1175 
1176 					eh = mtod(m0, struct ether_header *);
1177 					switch (ntohs(eh->ether_type)) {
1178 					case ETHERTYPE_IP:
1179 						start = ETHER_HDR_LEN;
1180 						break;
1181 					case ETHERTYPE_VLAN:
1182 						start = ETHER_HDR_LEN +
1183 							ETHER_VLAN_ENCAP_LEN;
1184 						break;
1185 					default:
1186 						/* unsupported, drop it */
1187 						m_free(m0);
1188 						continue;
1189 					}
1190 					start += M_CSUM_DATA_IPv4_IPHL(m0->m_pkthdr.csum_data);
1191 					offset = M_CSUM_DATA_IPv4_OFFSET(m0->m_pkthdr.csum_data) + start;
1192 					flags |= (start <<
1193 						  GEM_TD_CXSUM_STARTSHFT) |
1194 						 (offset <<
1195 						  GEM_TD_CXSUM_STUFFSHFT) |
1196 						 GEM_TD_CXSUM_ENABLE;
1197 				}
1198 #endif
1199 			}
1200 			if (seg == dmamap->dm_nsegs - 1) {
1201 				flags |= GEM_TD_END_OF_PACKET;
1202 			} else {
1203 				/* last flag set outside of loop */
1204 				sc->sc_txdescs[nexttx].gd_flags =
1205 					GEM_DMA_WRITE(sc, flags);
1206 			}
1207 			lasttx = nexttx;
1208 		}
1209 		if (m0->m_pkthdr.len < ETHER_MIN_TX) {
1210 			/* add padding buffer at end of chain */
1211 			flags &= ~GEM_TD_END_OF_PACKET;
1212 			sc->sc_txdescs[lasttx].gd_flags =
1213 			    GEM_DMA_WRITE(sc, flags);
1214 
1215 			sc->sc_txdescs[nexttx].gd_addr =
1216 			    GEM_DMA_WRITE(sc,
1217 			    sc->sc_nulldmamap->dm_segs[0].ds_addr);
1218 			flags = ((ETHER_MIN_TX - m0->m_pkthdr.len) &
1219 			    GEM_TD_BUFSIZE) | GEM_TD_END_OF_PACKET;
1220 			lasttx = nexttx;
1221 			nexttx = GEM_NEXTTX(nexttx);
1222 			seg++;
1223 		}
1224 		sc->sc_txdescs[lasttx].gd_flags = GEM_DMA_WRITE(sc, flags);
1225 
1226 		KASSERT(lasttx != -1);
1227 
1228 		/*
1229 		 * Store a pointer to the packet so we can free it later,
1230 		 * and remember what txdirty will be once the packet is
1231 		 * done.
1232 		 */
1233 		txs->txs_mbuf = m0;
1234 		txs->txs_firstdesc = sc->sc_txnext;
1235 		txs->txs_lastdesc = lasttx;
1236 		txs->txs_ndescs = seg;
1237 
1238 #ifdef GEM_DEBUG
1239 		if (ifp->if_flags & IFF_DEBUG) {
1240 			printf("     gem_start %p transmit chain:\n", txs);
1241 			for (seg = sc->sc_txnext;; seg = GEM_NEXTTX(seg)) {
1242 				printf("descriptor %d:\t", seg);
1243 				printf("gd_flags:   0x%016llx\t", (long long)
1244 					GEM_DMA_READ(sc, sc->sc_txdescs[seg].gd_flags));
1245 				printf("gd_addr: 0x%016llx\n", (long long)
1246 					GEM_DMA_READ(sc, sc->sc_txdescs[seg].gd_addr));
1247 				if (seg == lasttx)
1248 					break;
1249 			}
1250 		}
1251 #endif
1252 
1253 		/* Sync the descriptors we're using. */
1254 		GEM_CDTXSYNC(sc, sc->sc_txnext, dmamap->dm_nsegs,
1255 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
1256 
1257 		/* Advance the tx pointer. */
1258 		sc->sc_txfree -= txs->txs_ndescs;
1259 		sc->sc_txnext = nexttx;
1260 
1261 		SIMPLEQ_REMOVE_HEAD(&sc->sc_txfreeq, txs_q);
1262 		SIMPLEQ_INSERT_TAIL(&sc->sc_txdirtyq, txs, txs_q);
1263 
1264 		last_txs = txs;
1265 
1266 #if NBPFILTER > 0
1267 		/*
1268 		 * Pass the packet to any BPF listeners.
1269 		 */
1270 		if (ifp->if_bpf)
1271 			bpf_mtap(ifp->if_bpf, m0);
1272 #endif /* NBPFILTER > 0 */
1273 	}
1274 
1275 	if (txs == NULL || sc->sc_txfree == 0) {
1276 		/* No more slots left; notify upper layer. */
1277 		ifp->if_flags |= IFF_OACTIVE;
1278 		sc->sc_if_flags = ifp->if_flags;
1279 	}
1280 
1281 	if (sc->sc_txfree != ofree) {
1282 		DPRINTF(sc, ("%s: packets enqueued, IC on %d, OWN on %d\n",
1283 		    sc->sc_dev.dv_xname, lasttx, firsttx));
1284 		/*
1285 		 * The entire packet chain is set up.
1286 		 * Kick the transmitter.
1287 		 */
1288 		DPRINTF(sc, ("%s: gem_start: kicking tx %d\n",
1289 			sc->sc_dev.dv_xname, nexttx));
1290 		bus_space_write_4(sc->sc_bustag, sc->sc_h1, GEM_TX_KICK,
1291 			sc->sc_txnext);
1292 
1293 		/* Set a watchdog timer in case the chip flakes out. */
1294 		ifp->if_timer = 5;
1295 		DPRINTF(sc, ("%s: gem_start: watchdog %d\n",
1296 			sc->sc_dev.dv_xname, ifp->if_timer));
1297 	}
1298 }
1299 
1300 /*
1301  * Transmit interrupt.
1302  */
1303 int
1304 gem_tint(sc)
1305 	struct gem_softc *sc;
1306 {
1307 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1308 	bus_space_tag_t t = sc->sc_bustag;
1309 	bus_space_handle_t mac = sc->sc_h1;
1310 	struct gem_txsoft *txs;
1311 	int txlast;
1312 	int progress = 0;
1313 
1314 
1315 	DPRINTF(sc, ("%s: gem_tint\n", sc->sc_dev.dv_xname));
1316 
1317 	/*
1318 	 * Unload collision counters
1319 	 */
1320 	ifp->if_collisions +=
1321 		bus_space_read_4(t, mac, GEM_MAC_NORM_COLL_CNT) +
1322 		bus_space_read_4(t, mac, GEM_MAC_FIRST_COLL_CNT) +
1323 		bus_space_read_4(t, mac, GEM_MAC_EXCESS_COLL_CNT) +
1324 		bus_space_read_4(t, mac, GEM_MAC_LATE_COLL_CNT);
1325 
1326 	/*
1327 	 * then clear the hardware counters.
1328 	 */
1329 	bus_space_write_4(t, mac, GEM_MAC_NORM_COLL_CNT, 0);
1330 	bus_space_write_4(t, mac, GEM_MAC_FIRST_COLL_CNT, 0);
1331 	bus_space_write_4(t, mac, GEM_MAC_EXCESS_COLL_CNT, 0);
1332 	bus_space_write_4(t, mac, GEM_MAC_LATE_COLL_CNT, 0);
1333 
1334 	/*
1335 	 * Go through our Tx list and free mbufs for those
1336 	 * frames that have been transmitted.
1337 	 */
1338 	while ((txs = SIMPLEQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
1339 		GEM_CDTXSYNC(sc, txs->txs_lastdesc,
1340 		    txs->txs_ndescs,
1341 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1342 
1343 #ifdef GEM_DEBUG	/* XXX DMA synchronization? */
1344 		if (ifp->if_flags & IFF_DEBUG) {
1345 			int i;
1346 			printf("    txsoft %p transmit chain:\n", txs);
1347 			for (i = txs->txs_firstdesc;; i = GEM_NEXTTX(i)) {
1348 				printf("descriptor %d: ", i);
1349 				printf("gd_flags: 0x%016" PRIx64 "\t",
1350 					GEM_DMA_READ(sc, sc->sc_txdescs[i].gd_flags));
1351 				printf("gd_addr: 0x%016" PRIx64 "\n",
1352 					GEM_DMA_READ(sc, sc->sc_txdescs[i].gd_addr));
1353 				if (i == txs->txs_lastdesc)
1354 					break;
1355 			}
1356 		}
1357 #endif
1358 
1359 		/*
1360 		 * In theory, we could harveast some descriptors before
1361 		 * the ring is empty, but that's a bit complicated.
1362 		 *
1363 		 * GEM_TX_COMPLETION points to the last descriptor
1364 		 * processed +1.
1365 		 */
1366 		txlast = bus_space_read_4(t, mac, GEM_TX_COMPLETION);
1367 		DPRINTF(sc,
1368 			("gem_tint: txs->txs_lastdesc = %d, txlast = %d\n",
1369 				txs->txs_lastdesc, txlast));
1370 		if (txs->txs_firstdesc <= txs->txs_lastdesc) {
1371 			if ((txlast >= txs->txs_firstdesc) &&
1372 				(txlast <= txs->txs_lastdesc))
1373 				break;
1374 		} else {
1375 			/* Ick -- this command wraps */
1376 			if ((txlast >= txs->txs_firstdesc) ||
1377 				(txlast <= txs->txs_lastdesc))
1378 				break;
1379 		}
1380 
1381 		DPRINTF(sc, ("gem_tint: releasing a desc\n"));
1382 		SIMPLEQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
1383 
1384 		sc->sc_txfree += txs->txs_ndescs;
1385 
1386 		if (txs->txs_mbuf == NULL) {
1387 #ifdef DIAGNOSTIC
1388 				panic("gem_txintr: null mbuf");
1389 #endif
1390 		}
1391 
1392 		bus_dmamap_sync(sc->sc_dmatag, txs->txs_dmamap,
1393 		    0, txs->txs_dmamap->dm_mapsize,
1394 		    BUS_DMASYNC_POSTWRITE);
1395 		bus_dmamap_unload(sc->sc_dmatag, txs->txs_dmamap);
1396 		m_freem(txs->txs_mbuf);
1397 		txs->txs_mbuf = NULL;
1398 
1399 		SIMPLEQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
1400 
1401 		ifp->if_opackets++;
1402 		progress = 1;
1403 	}
1404 
1405 #if 0
1406 	DPRINTF(sc, ("gem_tint: GEM_TX_STATE_MACHINE %x "
1407 		"GEM_TX_DATA_PTR %" PRIx64 "GEM_TX_COMPLETION %" PRIx32 "\n",
1408 		bus_space_read_4(sc->sc_bustag, sc->sc_h1, GEM_TX_STATE_MACHINE),
1409 		((uint64_t)bus_space_read_4(sc->sc_bustag, sc->sc_h1,
1410 			GEM_TX_DATA_PTR_HI) << 32) |
1411 			     bus_space_read_4(sc->sc_bustag, sc->sc_h1,
1412 			GEM_TX_DATA_PTR_LO),
1413 		bus_space_read_4(sc->sc_bustag, sc->sc_h1, GEM_TX_COMPLETION)));
1414 #endif
1415 
1416 	if (progress) {
1417 		if (sc->sc_txfree == GEM_NTXDESC - 1)
1418 			sc->sc_txwin = 0;
1419 
1420 		ifp->if_flags &= ~IFF_OACTIVE;
1421 		sc->sc_if_flags = ifp->if_flags;
1422 		gem_start(ifp);
1423 
1424 		if (SIMPLEQ_EMPTY(&sc->sc_txdirtyq))
1425 			ifp->if_timer = 0;
1426 	}
1427 	DPRINTF(sc, ("%s: gem_tint: watchdog %d\n",
1428 		sc->sc_dev.dv_xname, ifp->if_timer));
1429 
1430 	return (1);
1431 }
1432 
1433 /*
1434  * Receive interrupt.
1435  */
1436 int
1437 gem_rint(sc)
1438 	struct gem_softc *sc;
1439 {
1440 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1441 	bus_space_tag_t t = sc->sc_bustag;
1442 	bus_space_handle_t h = sc->sc_h1;
1443 	struct gem_rxsoft *rxs;
1444 	struct mbuf *m;
1445 	u_int64_t rxstat;
1446 	u_int32_t rxcomp;
1447 	int i, len, progress = 0;
1448 
1449 	DPRINTF(sc, ("%s: gem_rint\n", sc->sc_dev.dv_xname));
1450 
1451 	/*
1452 	 * Read the completion register once.  This limits
1453 	 * how long the following loop can execute.
1454 	 */
1455 	rxcomp = bus_space_read_4(t, h, GEM_RX_COMPLETION);
1456 
1457 	/*
1458 	 * XXXX Read the lastrx only once at the top for speed.
1459 	 */
1460 	DPRINTF(sc, ("gem_rint: sc->rxptr %d, complete %d\n",
1461 		sc->sc_rxptr, rxcomp));
1462 
1463 	/*
1464 	 * Go into the loop at least once.
1465 	 */
1466 	for (i = sc->sc_rxptr; i == sc->sc_rxptr || i != rxcomp;
1467 	     i = GEM_NEXTRX(i)) {
1468 		rxs = &sc->sc_rxsoft[i];
1469 
1470 		GEM_CDRXSYNC(sc, i,
1471 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1472 
1473 		rxstat = GEM_DMA_READ(sc, sc->sc_rxdescs[i].gd_flags);
1474 
1475 		if (rxstat & GEM_RD_OWN) {
1476 			GEM_CDRXSYNC(sc, i, BUS_DMASYNC_PREREAD);
1477 			/*
1478 			 * We have processed all of the receive buffers.
1479 			 */
1480 			break;
1481 		}
1482 
1483 		progress++;
1484 		ifp->if_ipackets++;
1485 
1486 		if (rxstat & GEM_RD_BAD_CRC) {
1487 			ifp->if_ierrors++;
1488 			printf("%s: receive error: CRC error\n",
1489 				sc->sc_dev.dv_xname);
1490 			GEM_INIT_RXDESC(sc, i);
1491 			continue;
1492 		}
1493 
1494 		bus_dmamap_sync(sc->sc_dmatag, rxs->rxs_dmamap, 0,
1495 		    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);
1496 #ifdef GEM_DEBUG
1497 		if (ifp->if_flags & IFF_DEBUG) {
1498 			printf("    rxsoft %p descriptor %d: ", rxs, i);
1499 			printf("gd_flags: 0x%016llx\t", (long long)
1500 				GEM_DMA_READ(sc, sc->sc_rxdescs[i].gd_flags));
1501 			printf("gd_addr: 0x%016llx\n", (long long)
1502 				GEM_DMA_READ(sc, sc->sc_rxdescs[i].gd_addr));
1503 		}
1504 #endif
1505 
1506 		/* No errors; receive the packet. */
1507 		len = GEM_RD_BUFLEN(rxstat);
1508 
1509 		/*
1510 		 * Allocate a new mbuf cluster.  If that fails, we are
1511 		 * out of memory, and must drop the packet and recycle
1512 		 * the buffer that's already attached to this descriptor.
1513 		 */
1514 		m = rxs->rxs_mbuf;
1515 		if (gem_add_rxbuf(sc, i) != 0) {
1516 			GEM_COUNTER_INCR(sc, sc_ev_rxnobuf);
1517 			ifp->if_ierrors++;
1518 			GEM_INIT_RXDESC(sc, i);
1519 			bus_dmamap_sync(sc->sc_dmatag, rxs->rxs_dmamap, 0,
1520 			    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
1521 			continue;
1522 		}
1523 		m->m_data += 2; /* We're already off by two */
1524 
1525 		m->m_pkthdr.rcvif = ifp;
1526 		m->m_pkthdr.len = m->m_len = len;
1527 
1528 #if NBPFILTER > 0
1529 		/*
1530 		 * Pass this up to any BPF listeners, but only
1531 		 * pass it up the stack if its for us.
1532 		 */
1533 		if (ifp->if_bpf)
1534 			bpf_mtap(ifp->if_bpf, m);
1535 #endif /* NBPFILTER > 0 */
1536 
1537 #ifdef INET
1538 		/* hardware checksum */
1539 		if (ifp->if_csum_flags_rx & (M_CSUM_UDPv4 | M_CSUM_TCPv4)) {
1540 			struct ether_header *eh;
1541 			struct ip *ip;
1542 			struct udphdr *uh;
1543 			int32_t hlen, pktlen;
1544 
1545 			if (sc->sc_ethercom.ec_capenable & ETHERCAP_VLAN_MTU) {
1546 				pktlen = m->m_pkthdr.len - ETHER_HDR_LEN -
1547 					 ETHER_VLAN_ENCAP_LEN;
1548 				eh = (struct ether_header *) mtod(m, void *) +
1549 					ETHER_VLAN_ENCAP_LEN;
1550 			} else {
1551 				pktlen = m->m_pkthdr.len - ETHER_HDR_LEN;
1552 				eh = mtod(m, struct ether_header *);
1553 			}
1554 			if (ntohs(eh->ether_type) != ETHERTYPE_IP)
1555 				goto swcsum;
1556 			ip = (struct ip *) ((char *)eh + ETHER_HDR_LEN);
1557 
1558 			/* IPv4 only */
1559 			if (ip->ip_v != IPVERSION)
1560 				goto swcsum;
1561 
1562 			hlen = ip->ip_hl << 2;
1563 			if (hlen < sizeof(struct ip))
1564 				goto swcsum;
1565 
1566 			/*
1567 			 * bail if too short, has random trailing garbage,
1568 			 * truncated, fragment, or has ethernet pad.
1569 			 */
1570 			if ((ntohs(ip->ip_len) < hlen) ||
1571 			    (ntohs(ip->ip_len) != pktlen) ||
1572 			    (ntohs(ip->ip_off) & (IP_MF | IP_OFFMASK)))
1573 				goto swcsum;
1574 
1575 			switch (ip->ip_p) {
1576 			case IPPROTO_TCP:
1577 				if (! (ifp->if_csum_flags_rx & M_CSUM_TCPv4))
1578 					goto swcsum;
1579 				if (pktlen < (hlen + sizeof(struct tcphdr)))
1580 					goto swcsum;
1581 				m->m_pkthdr.csum_flags = M_CSUM_TCPv4;
1582 				break;
1583 			case IPPROTO_UDP:
1584 				if (! (ifp->if_csum_flags_rx & M_CSUM_UDPv4))
1585 					goto swcsum;
1586 				if (pktlen < (hlen + sizeof(struct udphdr)))
1587 					goto swcsum;
1588 				uh = (struct udphdr *)((char *)ip + hlen);
1589 				/* no checksum */
1590 				if (uh->uh_sum == 0)
1591 					goto swcsum;
1592 				m->m_pkthdr.csum_flags = M_CSUM_UDPv4;
1593 				break;
1594 			default:
1595 				goto swcsum;
1596 			}
1597 
1598 			/* the uncomplemented sum is expected */
1599 			m->m_pkthdr.csum_data = (~rxstat) & GEM_RD_CHECKSUM;
1600 
1601 			/* if the pkt had ip options, we have to deduct them */
1602 			if (hlen > sizeof(struct ip)) {
1603 				uint16_t *opts;
1604 				uint32_t optsum, temp;
1605 
1606 				optsum = 0;
1607 				temp = hlen - sizeof(struct ip);
1608 				opts = (uint16_t *) ((char *) ip +
1609 					sizeof(struct ip));
1610 
1611 				while (temp > 1) {
1612 					optsum += ntohs(*opts++);
1613 					temp -= 2;
1614 				}
1615 				while (optsum >> 16)
1616 					optsum = (optsum >> 16) +
1617 						 (optsum & 0xffff);
1618 
1619 				/* Deduct ip opts sum from hwsum (rfc 1624). */
1620 				m->m_pkthdr.csum_data =
1621 					~((~m->m_pkthdr.csum_data) - ~optsum);
1622 
1623 				while (m->m_pkthdr.csum_data >> 16)
1624 					m->m_pkthdr.csum_data =
1625 						(m->m_pkthdr.csum_data >> 16) +
1626 						(m->m_pkthdr.csum_data &
1627 						 0xffff);
1628 			}
1629 
1630 			m->m_pkthdr.csum_flags |= M_CSUM_DATA |
1631 						  M_CSUM_NO_PSEUDOHDR;
1632 		} else
1633 swcsum:
1634 			m->m_pkthdr.csum_flags = 0;
1635 #endif
1636 		/* Pass it on. */
1637 		(*ifp->if_input)(ifp, m);
1638 	}
1639 
1640 	if (progress) {
1641 		/* Update the receive pointer. */
1642 		if (i == sc->sc_rxptr) {
1643 			GEM_COUNTER_INCR(sc, sc_ev_rxfull);
1644 #ifdef GEM_DEBUG
1645 			if (ifp->if_flags & IFF_DEBUG)
1646 				printf("%s: rint: ring wrap\n",
1647 				    sc->sc_dev.dv_xname);
1648 #endif
1649 		}
1650 		sc->sc_rxptr = i;
1651 		bus_space_write_4(t, h, GEM_RX_KICK, GEM_PREVRX(i));
1652 	}
1653 #ifdef GEM_COUNTERS
1654 	if (progress <= 4) {
1655 		GEM_COUNTER_INCR(sc, sc_ev_rxhist[progress]);
1656 	} else if (progress < 32) {
1657 		if (progress < 16)
1658 			GEM_COUNTER_INCR(sc, sc_ev_rxhist[5]);
1659 		else
1660 			GEM_COUNTER_INCR(sc, sc_ev_rxhist[6]);
1661 
1662 	} else {
1663 		if (progress < 64)
1664 			GEM_COUNTER_INCR(sc, sc_ev_rxhist[7]);
1665 		else
1666 			GEM_COUNTER_INCR(sc, sc_ev_rxhist[8]);
1667 	}
1668 #endif
1669 
1670 	DPRINTF(sc, ("gem_rint: done sc->rxptr %d, complete %d\n",
1671 		sc->sc_rxptr, bus_space_read_4(t, h, GEM_RX_COMPLETION)));
1672 
1673 	return (1);
1674 }
1675 
1676 
1677 /*
1678  * gem_add_rxbuf:
1679  *
1680  *	Add a receive buffer to the indicated descriptor.
1681  */
1682 int
1683 gem_add_rxbuf(struct gem_softc *sc, int idx)
1684 {
1685 	struct gem_rxsoft *rxs = &sc->sc_rxsoft[idx];
1686 	struct mbuf *m;
1687 	int error;
1688 
1689 	MGETHDR(m, M_DONTWAIT, MT_DATA);
1690 	if (m == NULL)
1691 		return (ENOBUFS);
1692 
1693 	MCLAIM(m, &sc->sc_ethercom.ec_rx_mowner);
1694 	MCLGET(m, M_DONTWAIT);
1695 	if ((m->m_flags & M_EXT) == 0) {
1696 		m_freem(m);
1697 		return (ENOBUFS);
1698 	}
1699 
1700 #ifdef GEM_DEBUG
1701 /* bzero the packet to check DMA */
1702 	memset(m->m_ext.ext_buf, 0, m->m_ext.ext_size);
1703 #endif
1704 
1705 	if (rxs->rxs_mbuf != NULL)
1706 		bus_dmamap_unload(sc->sc_dmatag, rxs->rxs_dmamap);
1707 
1708 	rxs->rxs_mbuf = m;
1709 
1710 	error = bus_dmamap_load(sc->sc_dmatag, rxs->rxs_dmamap,
1711 	    m->m_ext.ext_buf, m->m_ext.ext_size, NULL,
1712 	    BUS_DMA_READ|BUS_DMA_NOWAIT);
1713 	if (error) {
1714 		printf("%s: can't load rx DMA map %d, error = %d\n",
1715 		    sc->sc_dev.dv_xname, idx, error);
1716 		panic("gem_add_rxbuf");	/* XXX */
1717 	}
1718 
1719 	bus_dmamap_sync(sc->sc_dmatag, rxs->rxs_dmamap, 0,
1720 	    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
1721 
1722 	GEM_INIT_RXDESC(sc, idx);
1723 
1724 	return (0);
1725 }
1726 
1727 
1728 int
1729 gem_eint(sc, status)
1730 	struct gem_softc *sc;
1731 	u_int status;
1732 {
1733 	char bits[128];
1734 
1735 	if ((status & GEM_INTR_MIF) != 0) {
1736 		printf("%s: XXXlink status changed\n", sc->sc_dev.dv_xname);
1737 		return (1);
1738 	}
1739 
1740 	printf("%s: status=%s\n", sc->sc_dev.dv_xname,
1741 		bitmask_snprintf(status, GEM_INTR_BITS, bits, sizeof(bits)));
1742 	return (1);
1743 }
1744 
1745 
1746 int
1747 gem_intr(v)
1748 	void *v;
1749 {
1750 	struct gem_softc *sc = (struct gem_softc *)v;
1751 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1752 	bus_space_tag_t t = sc->sc_bustag;
1753 	bus_space_handle_t seb = sc->sc_h1;
1754 	u_int32_t status;
1755 	int r = 0;
1756 #ifdef GEM_DEBUG
1757 	char bits[128];
1758 #endif
1759 
1760 	sc->sc_ev_intr.ev_count++;
1761 
1762 	status = bus_space_read_4(t, seb, GEM_STATUS);
1763 	DPRINTF(sc, ("%s: gem_intr: cplt 0x%x status %s\n",
1764 		sc->sc_dev.dv_xname, (status >> 19),
1765 		bitmask_snprintf(status, GEM_INTR_BITS, bits, sizeof(bits))));
1766 
1767 	if ((status & (GEM_INTR_RX_TAG_ERR | GEM_INTR_BERR)) != 0)
1768 		r |= gem_eint(sc, status);
1769 
1770 	if ((status & (GEM_INTR_TX_EMPTY | GEM_INTR_TX_INTME)) != 0) {
1771 		GEM_COUNTER_INCR(sc, sc_ev_txint);
1772 		r |= gem_tint(sc);
1773 	}
1774 
1775 	if ((status & (GEM_INTR_RX_DONE | GEM_INTR_RX_NOBUF)) != 0) {
1776 		GEM_COUNTER_INCR(sc, sc_ev_rxint);
1777 		r |= gem_rint(sc);
1778 	}
1779 
1780 	/* We should eventually do more than just print out error stats. */
1781 	if (status & GEM_INTR_TX_MAC) {
1782 		int txstat = bus_space_read_4(t, seb, GEM_MAC_TX_STATUS);
1783 		if (txstat & ~GEM_MAC_TX_XMIT_DONE)
1784 			printf("%s: MAC tx fault, status %x\n",
1785 			    sc->sc_dev.dv_xname, txstat);
1786 		if (txstat & (GEM_MAC_TX_UNDERRUN | GEM_MAC_TX_PKT_TOO_LONG))
1787 			gem_init(ifp);
1788 	}
1789 	if (status & GEM_INTR_RX_MAC) {
1790 		int rxstat = bus_space_read_4(t, seb, GEM_MAC_RX_STATUS);
1791 		if (rxstat & ~GEM_MAC_RX_DONE)
1792 			printf("%s: MAC rx fault, status %x\n",
1793 			    sc->sc_dev.dv_xname, rxstat);
1794 		/*
1795 		 * On some chip revisions GEM_MAC_RX_OVERFLOW happen often
1796 		 * due to a silicon bug so handle them silently.
1797 		 */
1798 		if (rxstat & GEM_MAC_RX_OVERFLOW)
1799 			gem_init(ifp);
1800 		else if (rxstat & ~(GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT))
1801 			printf("%s: MAC rx fault, status %x\n",
1802 			    sc->sc_dev.dv_xname, rxstat);
1803 	}
1804 #if NRND > 0
1805 	rnd_add_uint32(&sc->rnd_source, status);
1806 #endif
1807 	return (r);
1808 }
1809 
1810 
1811 void
1812 gem_watchdog(ifp)
1813 	struct ifnet *ifp;
1814 {
1815 	struct gem_softc *sc = ifp->if_softc;
1816 
1817 	DPRINTF(sc, ("gem_watchdog: GEM_RX_CONFIG %x GEM_MAC_RX_STATUS %x "
1818 		"GEM_MAC_RX_CONFIG %x\n",
1819 		bus_space_read_4(sc->sc_bustag, sc->sc_h1, GEM_RX_CONFIG),
1820 		bus_space_read_4(sc->sc_bustag, sc->sc_h1, GEM_MAC_RX_STATUS),
1821 		bus_space_read_4(sc->sc_bustag, sc->sc_h1, GEM_MAC_RX_CONFIG)));
1822 
1823 	log(LOG_ERR, "%s: device timeout\n", sc->sc_dev.dv_xname);
1824 	++ifp->if_oerrors;
1825 
1826 	/* Try to get more packets going. */
1827 	gem_start(ifp);
1828 }
1829 
1830 /*
1831  * Initialize the MII Management Interface
1832  */
1833 void
1834 gem_mifinit(sc)
1835 	struct gem_softc *sc;
1836 {
1837 	bus_space_tag_t t = sc->sc_bustag;
1838 	bus_space_handle_t mif = sc->sc_h1;
1839 
1840 	/* Configure the MIF in frame mode */
1841 	sc->sc_mif_config = bus_space_read_4(t, mif, GEM_MIF_CONFIG);
1842 	sc->sc_mif_config &= ~GEM_MIF_CONFIG_BB_ENA;
1843 	bus_space_write_4(t, mif, GEM_MIF_CONFIG, sc->sc_mif_config);
1844 }
1845 
1846 /*
1847  * MII interface
1848  *
1849  * The GEM MII interface supports at least three different operating modes:
1850  *
1851  * Bitbang mode is implemented using data, clock and output enable registers.
1852  *
1853  * Frame mode is implemented by loading a complete frame into the frame
1854  * register and polling the valid bit for completion.
1855  *
1856  * Polling mode uses the frame register but completion is indicated by
1857  * an interrupt.
1858  *
1859  */
1860 static int
1861 gem_mii_readreg(self, phy, reg)
1862 	struct device *self;
1863 	int phy, reg;
1864 {
1865 	struct gem_softc *sc = (void *)self;
1866 	bus_space_tag_t t = sc->sc_bustag;
1867 	bus_space_handle_t mif = sc->sc_h1;
1868 	int n;
1869 	u_int32_t v;
1870 
1871 #ifdef GEM_DEBUG1
1872 	if (sc->sc_debug)
1873 		printf("gem_mii_readreg: phy %d reg %d\n", phy, reg);
1874 #endif
1875 
1876 #if 0
1877 	/* Select the desired PHY in the MIF configuration register */
1878 	v = bus_space_read_4(t, mif, GEM_MIF_CONFIG);
1879 	/* Clear PHY select bit */
1880 	v &= ~GEM_MIF_CONFIG_PHY_SEL;
1881 	if (phy == GEM_PHYAD_EXTERNAL)
1882 		/* Set PHY select bit to get at external device */
1883 		v |= GEM_MIF_CONFIG_PHY_SEL;
1884 	bus_space_write_4(t, mif, GEM_MIF_CONFIG, v);
1885 #endif
1886 
1887 	/* Construct the frame command */
1888 	v = (reg << GEM_MIF_REG_SHIFT)	| (phy << GEM_MIF_PHY_SHIFT) |
1889 		GEM_MIF_FRAME_READ;
1890 
1891 	bus_space_write_4(t, mif, GEM_MIF_FRAME, v);
1892 	for (n = 0; n < 100; n++) {
1893 		DELAY(1);
1894 		v = bus_space_read_4(t, mif, GEM_MIF_FRAME);
1895 		if (v & GEM_MIF_FRAME_TA0)
1896 			return (v & GEM_MIF_FRAME_DATA);
1897 	}
1898 
1899 	printf("%s: mii_read timeout\n", sc->sc_dev.dv_xname);
1900 	return (0);
1901 }
1902 
1903 static void
1904 gem_mii_writereg(self, phy, reg, val)
1905 	struct device *self;
1906 	int phy, reg, val;
1907 {
1908 	struct gem_softc *sc = (void *)self;
1909 	bus_space_tag_t t = sc->sc_bustag;
1910 	bus_space_handle_t mif = sc->sc_h1;
1911 	int n;
1912 	u_int32_t v;
1913 
1914 #ifdef GEM_DEBUG1
1915 	if (sc->sc_debug)
1916 		printf("gem_mii_writereg: phy %d reg %d val %x\n",
1917 			phy, reg, val);
1918 #endif
1919 
1920 #if 0
1921 	/* Select the desired PHY in the MIF configuration register */
1922 	v = bus_space_read_4(t, mif, GEM_MIF_CONFIG);
1923 	/* Clear PHY select bit */
1924 	v &= ~GEM_MIF_CONFIG_PHY_SEL;
1925 	if (phy == GEM_PHYAD_EXTERNAL)
1926 		/* Set PHY select bit to get at external device */
1927 		v |= GEM_MIF_CONFIG_PHY_SEL;
1928 	bus_space_write_4(t, mif, GEM_MIF_CONFIG, v);
1929 #endif
1930 	/* Construct the frame command */
1931 	v = GEM_MIF_FRAME_WRITE			|
1932 	    (phy << GEM_MIF_PHY_SHIFT)		|
1933 	    (reg << GEM_MIF_REG_SHIFT)		|
1934 	    (val & GEM_MIF_FRAME_DATA);
1935 
1936 	bus_space_write_4(t, mif, GEM_MIF_FRAME, v);
1937 	for (n = 0; n < 100; n++) {
1938 		DELAY(1);
1939 		v = bus_space_read_4(t, mif, GEM_MIF_FRAME);
1940 		if (v & GEM_MIF_FRAME_TA0)
1941 			return;
1942 	}
1943 
1944 	printf("%s: mii_write timeout\n", sc->sc_dev.dv_xname);
1945 }
1946 
1947 static void
1948 gem_mii_statchg(dev)
1949 	struct device *dev;
1950 {
1951 	struct gem_softc *sc = (void *)dev;
1952 #ifdef GEM_DEBUG
1953 	int instance = IFM_INST(sc->sc_mii.mii_media.ifm_cur->ifm_media);
1954 #endif
1955 	bus_space_tag_t t = sc->sc_bustag;
1956 	bus_space_handle_t mac = sc->sc_h1;
1957 	u_int32_t v;
1958 
1959 #ifdef GEM_DEBUG
1960 	if (sc->sc_debug)
1961 		printf("gem_mii_statchg: status change: phy = %d\n",
1962 			sc->sc_phys[instance]);
1963 #endif
1964 
1965 
1966 	/* Set tx full duplex options */
1967 	bus_space_write_4(t, mac, GEM_MAC_TX_CONFIG, 0);
1968 	delay(10000); /* reg must be cleared and delay before changing. */
1969 	v = GEM_MAC_TX_ENA_IPG0|GEM_MAC_TX_NGU|GEM_MAC_TX_NGU_LIMIT|
1970 		GEM_MAC_TX_ENABLE;
1971 	if ((IFM_OPTIONS(sc->sc_mii.mii_media_active) & IFM_FDX) != 0) {
1972 		v |= GEM_MAC_TX_IGN_CARRIER|GEM_MAC_TX_IGN_COLLIS;
1973 	}
1974 	bus_space_write_4(t, mac, GEM_MAC_TX_CONFIG, v);
1975 
1976 	/* XIF Configuration */
1977  /* We should really calculate all this rather than rely on defaults */
1978 	v = bus_space_read_4(t, mac, GEM_MAC_XIF_CONFIG);
1979 	v = GEM_MAC_XIF_LINK_LED;
1980 	v |= GEM_MAC_XIF_TX_MII_ENA;
1981 
1982 	/* If an external transceiver is connected, enable its MII drivers */
1983 	sc->sc_mif_config = bus_space_read_4(t, mac, GEM_MIF_CONFIG);
1984 	if ((sc->sc_mif_config & GEM_MIF_CONFIG_MDI1) != 0) {
1985 		/* External MII needs echo disable if half duplex. */
1986 		if ((IFM_OPTIONS(sc->sc_mii.mii_media_active) & IFM_FDX) != 0)
1987 			/* turn on full duplex LED */
1988 			v |= GEM_MAC_XIF_FDPLX_LED;
1989 		else
1990 	 		/* half duplex -- disable echo */
1991 		 	v |= GEM_MAC_XIF_ECHO_DISABL;
1992 
1993 		if (sc->sc_ethercom.ec_if.if_baudrate == IF_Mbps(1000))
1994 			v |= GEM_MAC_XIF_GMII_MODE;
1995 		else
1996 			v &= ~GEM_MAC_XIF_GMII_MODE;
1997 	} else
1998 		/* Internal MII needs buf enable */
1999 		v |= GEM_MAC_XIF_MII_BUF_ENA;
2000 	bus_space_write_4(t, mac, GEM_MAC_XIF_CONFIG, v);
2001 }
2002 
2003 int
2004 gem_mediachange(ifp)
2005 	struct ifnet *ifp;
2006 {
2007 	struct gem_softc *sc = ifp->if_softc;
2008 
2009 	if (IFM_TYPE(sc->sc_media.ifm_media) != IFM_ETHER)
2010 		return (EINVAL);
2011 
2012 	return (mii_mediachg(&sc->sc_mii));
2013 }
2014 
2015 void
2016 gem_mediastatus(ifp, ifmr)
2017 	struct ifnet *ifp;
2018 	struct ifmediareq *ifmr;
2019 {
2020 	struct gem_softc *sc = ifp->if_softc;
2021 
2022 	if ((ifp->if_flags & IFF_UP) == 0)
2023 		return;
2024 
2025 	mii_pollstat(&sc->sc_mii);
2026 	ifmr->ifm_active = sc->sc_mii.mii_media_active;
2027 	ifmr->ifm_status = sc->sc_mii.mii_media_status;
2028 }
2029 
2030 /*
2031  * Process an ioctl request.
2032  */
2033 int
2034 gem_ioctl(ifp, cmd, data)
2035 	struct ifnet *ifp;
2036 	u_long cmd;
2037 	void *data;
2038 {
2039 	struct gem_softc *sc = ifp->if_softc;
2040 	struct ifreq *ifr = (struct ifreq *)data;
2041 	int s, error = 0;
2042 
2043 	s = splnet();
2044 
2045 	switch (cmd) {
2046 	case SIOCGIFMEDIA:
2047 	case SIOCSIFMEDIA:
2048 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_media, cmd);
2049 		break;
2050 	case SIOCSIFFLAGS:
2051 #define RESETIGN (IFF_CANTCHANGE|IFF_DEBUG)
2052 		if (((ifp->if_flags & (IFF_UP|IFF_RUNNING))
2053 		    == (IFF_UP|IFF_RUNNING))
2054 		    && ((ifp->if_flags & (~RESETIGN))
2055 		    == (sc->sc_if_flags & (~RESETIGN)))) {
2056 			gem_setladrf(sc);
2057 			break;
2058 		}
2059 #undef RESETIGN
2060 		/*FALLTHROUGH*/
2061 	default:
2062 		error = ether_ioctl(ifp, cmd, data);
2063 		if (error == ENETRESET) {
2064 			/*
2065 			 * Multicast list has changed; set the hardware filter
2066 			 * accordingly.
2067 			 */
2068 			if (ifp->if_flags & IFF_RUNNING)
2069 				gem_setladrf(sc);
2070 			error = 0;
2071 		}
2072 		break;
2073 	}
2074 
2075 	/* Try to get things going again */
2076 	if (ifp->if_flags & IFF_UP)
2077 		gem_start(ifp);
2078 	splx(s);
2079 	return (error);
2080 }
2081 
2082 
2083 void
2084 gem_shutdown(arg)
2085 	void *arg;
2086 {
2087 	struct gem_softc *sc = (struct gem_softc *)arg;
2088 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
2089 
2090 	gem_stop(ifp, 1);
2091 }
2092 
2093 /*
2094  * Set up the logical address filter.
2095  */
2096 void
2097 gem_setladrf(sc)
2098 	struct gem_softc *sc;
2099 {
2100 	struct ethercom *ec = &sc->sc_ethercom;
2101 	struct ifnet *ifp = &ec->ec_if;
2102 	struct ether_multi *enm;
2103 	struct ether_multistep step;
2104 	bus_space_tag_t t = sc->sc_bustag;
2105 	bus_space_handle_t h = sc->sc_h1;
2106 	u_int32_t crc;
2107 	u_int32_t hash[16];
2108 	u_int32_t v;
2109 	int i;
2110 
2111 	/* Get current RX configuration */
2112 	v = bus_space_read_4(t, h, GEM_MAC_RX_CONFIG);
2113 
2114 	/*
2115 	 * Turn off promiscuous mode, promiscuous group mode (all multicast),
2116 	 * and hash filter.  Depending on the case, the right bit will be
2117 	 * enabled.
2118 	 */
2119 	v &= ~(GEM_MAC_RX_PROMISCUOUS|GEM_MAC_RX_HASH_FILTER|
2120 	    GEM_MAC_RX_PROMISC_GRP);
2121 
2122 	if ((ifp->if_flags & IFF_PROMISC) != 0) {
2123 		/* Turn on promiscuous mode */
2124 		v |= GEM_MAC_RX_PROMISCUOUS;
2125 		ifp->if_flags |= IFF_ALLMULTI;
2126 		goto chipit;
2127 	}
2128 
2129 	/*
2130 	 * Set up multicast address filter by passing all multicast addresses
2131 	 * through a crc generator, and then using the high order 8 bits as an
2132 	 * index into the 256 bit logical address filter.  The high order 4
2133 	 * bits selects the word, while the other 4 bits select the bit within
2134 	 * the word (where bit 0 is the MSB).
2135 	 */
2136 
2137 	/* Clear hash table */
2138 	memset(hash, 0, sizeof(hash));
2139 
2140 	ETHER_FIRST_MULTI(step, ec, enm);
2141 	while (enm != NULL) {
2142 		if (memcmp(enm->enm_addrlo, enm->enm_addrhi, ETHER_ADDR_LEN)) {
2143 			/*
2144 			 * We must listen to a range of multicast addresses.
2145 			 * For now, just accept all multicasts, rather than
2146 			 * trying to set only those filter bits needed to match
2147 			 * the range.  (At this time, the only use of address
2148 			 * ranges is for IP multicast routing, for which the
2149 			 * range is big enough to require all bits set.)
2150 			 * XXX use the addr filter for this
2151 			 */
2152 			ifp->if_flags |= IFF_ALLMULTI;
2153 			v |= GEM_MAC_RX_PROMISC_GRP;
2154 			goto chipit;
2155 		}
2156 
2157 		/* Get the LE CRC32 of the address */
2158 		crc = ether_crc32_le(enm->enm_addrlo, sizeof(enm->enm_addrlo));
2159 
2160 		/* Just want the 8 most significant bits. */
2161 		crc >>= 24;
2162 
2163 		/* Set the corresponding bit in the filter. */
2164 		hash[crc >> 4] |= 1 << (15 - (crc & 15));
2165 
2166 		ETHER_NEXT_MULTI(step, enm);
2167 	}
2168 
2169 	v |= GEM_MAC_RX_HASH_FILTER;
2170 	ifp->if_flags &= ~IFF_ALLMULTI;
2171 
2172 	/* Now load the hash table into the chip (if we are using it) */
2173 	for (i = 0; i < 16; i++) {
2174 		bus_space_write_4(t, h,
2175 		    GEM_MAC_HASH0 + i * (GEM_MAC_HASH1-GEM_MAC_HASH0),
2176 		    hash[i]);
2177 	}
2178 
2179 chipit:
2180 	sc->sc_if_flags = ifp->if_flags;
2181 	bus_space_write_4(t, h, GEM_MAC_RX_CONFIG, v);
2182 }
2183 
2184 #if notyet
2185 
2186 /*
2187  * gem_power:
2188  *
2189  *	Power management (suspend/resume) hook.
2190  */
2191 void
2192 gem_power(why, arg)
2193 	int why;
2194 	void *arg;
2195 {
2196 	struct gem_softc *sc = arg;
2197 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
2198 	int s;
2199 
2200 	s = splnet();
2201 	switch (why) {
2202 	case PWR_SUSPEND:
2203 	case PWR_STANDBY:
2204 		gem_stop(ifp, 1);
2205 		if (sc->sc_power != NULL)
2206 			(*sc->sc_power)(sc, why);
2207 		break;
2208 	case PWR_RESUME:
2209 		if (ifp->if_flags & IFF_UP) {
2210 			if (sc->sc_power != NULL)
2211 				(*sc->sc_power)(sc, why);
2212 			gem_init(ifp);
2213 		}
2214 		break;
2215 	case PWR_SOFTSUSPEND:
2216 	case PWR_SOFTSTANDBY:
2217 	case PWR_SOFTRESUME:
2218 		break;
2219 	}
2220 	splx(s);
2221 }
2222 #endif
2223