xref: /freebsd/sys/dev/gem/if_gem.c (revision fb2971ccd2bab42f5406f919812ceb8e014773ea)
1 /*-
2  * Copyright (C) 2001 Eduardo Horvath.
3  * Copyright (c) 2001-2003 Thomas Moestl
4  * Copyright (c) 2007 Marius Strobl <marius@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR  ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR  BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  *	from: NetBSD: gem.c,v 1.21 2002/06/01 23:50:58 lukem Exp
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 /*
35  * Driver for Apple GMAC, Sun ERI and Sun GEM Ethernet controllers
36  */
37 
38 #if 0
39 #define	GEM_DEBUG
40 #endif
41 
42 #if 0	/* XXX: In case of emergency, re-enable this. */
43 #define	GEM_RINT_TIMEOUT
44 #endif
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/bus.h>
49 #include <sys/callout.h>
50 #include <sys/endian.h>
51 #include <sys/mbuf.h>
52 #include <sys/malloc.h>
53 #include <sys/kernel.h>
54 #include <sys/lock.h>
55 #include <sys/module.h>
56 #include <sys/mutex.h>
57 #include <sys/socket.h>
58 #include <sys/sockio.h>
59 #include <sys/rman.h>
60 
61 #include <net/bpf.h>
62 #include <net/ethernet.h>
63 #include <net/if.h>
64 #include <net/if_arp.h>
65 #include <net/if_dl.h>
66 #include <net/if_media.h>
67 #include <net/if_types.h>
68 #include <net/if_vlan_var.h>
69 
70 #include <netinet/in.h>
71 #include <netinet/in_systm.h>
72 #include <netinet/ip.h>
73 #include <netinet/tcp.h>
74 #include <netinet/udp.h>
75 
76 #include <machine/bus.h>
77 
78 #include <dev/mii/mii.h>
79 #include <dev/mii/miivar.h>
80 
81 #include <dev/gem/if_gemreg.h>
82 #include <dev/gem/if_gemvar.h>
83 
84 CTASSERT(powerof2(GEM_NRXDESC) && GEM_NRXDESC >= 32 && GEM_NRXDESC <= 8192);
85 CTASSERT(powerof2(GEM_NTXDESC) && GEM_NTXDESC >= 32 && GEM_NTXDESC <= 8192);
86 
87 #define	GEM_TRIES	10000
88 
89 /*
90  * The hardware supports basic TCP/UDP checksum offloading.  However,
91  * the hardware doesn't compensate the checksum for UDP datagram which
92  * can yield to 0x0.  As a safe guard, UDP checksum offload is disabled
93  * by default.  It can be reactivated by setting special link option
94  * link0 with ifconfig(8).
95  */
96 #define	GEM_CSUM_FEATURES	(CSUM_TCP)
97 
98 static int	gem_add_rxbuf(struct gem_softc *sc, int idx);
99 static int	gem_bitwait(struct gem_softc *sc, u_int bank, bus_addr_t r,
100 		    uint32_t clr, uint32_t set);
101 static void	gem_cddma_callback(void *xsc, bus_dma_segment_t *segs,
102 		    int nsegs, int error);
103 static int	gem_disable_rx(struct gem_softc *sc);
104 static int	gem_disable_tx(struct gem_softc *sc);
105 static void	gem_eint(struct gem_softc *sc, u_int status);
106 static void	gem_init(void *xsc);
107 static void	gem_init_locked(struct gem_softc *sc);
108 static void	gem_init_regs(struct gem_softc *sc);
109 static int	gem_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data);
110 static int	gem_load_txmbuf(struct gem_softc *sc, struct mbuf **m_head);
111 static int	gem_meminit(struct gem_softc *sc);
112 static void	gem_mifinit(struct gem_softc *sc);
113 static void	gem_reset(struct gem_softc *sc);
114 static int	gem_reset_rx(struct gem_softc *sc);
115 static void	gem_reset_rxdma(struct gem_softc *sc);
116 static int	gem_reset_tx(struct gem_softc *sc);
117 static u_int	gem_ringsize(u_int sz);
118 static void	gem_rint(struct gem_softc *sc);
119 #ifdef GEM_RINT_TIMEOUT
120 static void	gem_rint_timeout(void *arg);
121 #endif
122 static inline void gem_rxcksum(struct mbuf *m, uint64_t flags);
123 static void	gem_rxdrain(struct gem_softc *sc);
124 static void	gem_setladrf(struct gem_softc *sc);
125 static void	gem_start(struct ifnet *ifp);
126 static void	gem_start_locked(struct ifnet *ifp);
127 static void	gem_stop(struct ifnet *ifp, int disable);
128 static void	gem_tick(void *arg);
129 static void	gem_tint(struct gem_softc *sc);
130 static inline void gem_txkick(struct gem_softc *sc);
131 static int	gem_watchdog(struct gem_softc *sc);
132 
133 devclass_t gem_devclass;
134 DRIVER_MODULE(miibus, gem, miibus_driver, miibus_devclass, 0, 0);
135 MODULE_DEPEND(gem, miibus, 1, 1, 1);
136 
137 #ifdef GEM_DEBUG
138 #include <sys/ktr.h>
139 #define	KTR_GEM		KTR_SPARE2
140 #endif
141 
142 #define	GEM_BANK1_BITWAIT(sc, r, clr, set)				\
143 	gem_bitwait((sc), GEM_RES_BANK1, (r), (clr), (set))
144 #define	GEM_BANK2_BITWAIT(sc, r, clr, set)				\
145 	gem_bitwait((sc), GEM_RES_BANK2, (r), (clr), (set))
146 
147 int
148 gem_attach(struct gem_softc *sc)
149 {
150 	struct gem_txsoft *txs;
151 	struct ifnet *ifp;
152 	int error, i, phy;
153 	uint32_t v;
154 
155 	if (bootverbose)
156 		device_printf(sc->sc_dev, "flags=0x%x\n", sc->sc_flags);
157 
158 	/* Set up ifnet structure. */
159 	ifp = sc->sc_ifp = if_alloc(IFT_ETHER);
160 	if (ifp == NULL)
161 		return (ENOSPC);
162 	sc->sc_csum_features = GEM_CSUM_FEATURES;
163 	ifp->if_softc = sc;
164 	if_initname(ifp, device_get_name(sc->sc_dev),
165 	    device_get_unit(sc->sc_dev));
166 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
167 	ifp->if_start = gem_start;
168 	ifp->if_ioctl = gem_ioctl;
169 	ifp->if_init = gem_init;
170 	IFQ_SET_MAXLEN(&ifp->if_snd, GEM_TXQUEUELEN);
171 	ifp->if_snd.ifq_drv_maxlen = GEM_TXQUEUELEN;
172 	IFQ_SET_READY(&ifp->if_snd);
173 
174 	callout_init_mtx(&sc->sc_tick_ch, &sc->sc_mtx, 0);
175 #ifdef GEM_RINT_TIMEOUT
176 	callout_init_mtx(&sc->sc_rx_ch, &sc->sc_mtx, 0);
177 #endif
178 
179 	/* Make sure the chip is stopped. */
180 	gem_reset(sc);
181 
182 	error = bus_dma_tag_create(bus_get_dma_tag(sc->sc_dev), 1, 0,
183 	    BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL,
184 	    BUS_SPACE_MAXSIZE_32BIT, 0, BUS_SPACE_MAXSIZE_32BIT, 0, NULL,
185 	    NULL, &sc->sc_pdmatag);
186 	if (error != 0)
187 		goto fail_ifnet;
188 
189 	error = bus_dma_tag_create(sc->sc_pdmatag, 1, 0,
190 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL, MCLBYTES,
191 	    1, MCLBYTES, BUS_DMA_ALLOCNOW, NULL, NULL, &sc->sc_rdmatag);
192 	if (error != 0)
193 		goto fail_ptag;
194 
195 	error = bus_dma_tag_create(sc->sc_pdmatag, 1, 0,
196 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
197 	    MCLBYTES * GEM_NTXSEGS, GEM_NTXSEGS, MCLBYTES,
198 	    BUS_DMA_ALLOCNOW, NULL, NULL, &sc->sc_tdmatag);
199 	if (error != 0)
200 		goto fail_rtag;
201 
202 	error = bus_dma_tag_create(sc->sc_pdmatag, PAGE_SIZE, 0,
203 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
204 	    sizeof(struct gem_control_data), 1,
205 	    sizeof(struct gem_control_data), 0,
206 	    NULL, NULL, &sc->sc_cdmatag);
207 	if (error != 0)
208 		goto fail_ttag;
209 
210 	/*
211 	 * Allocate the control data structures, create and load the
212 	 * DMA map for it.
213 	 */
214 	if ((error = bus_dmamem_alloc(sc->sc_cdmatag,
215 	    (void **)&sc->sc_control_data,
216 	    BUS_DMA_WAITOK | BUS_DMA_COHERENT | BUS_DMA_ZERO,
217 	    &sc->sc_cddmamap)) != 0) {
218 		device_printf(sc->sc_dev,
219 		    "unable to allocate control data, error = %d\n", error);
220 		goto fail_ctag;
221 	}
222 
223 	sc->sc_cddma = 0;
224 	if ((error = bus_dmamap_load(sc->sc_cdmatag, sc->sc_cddmamap,
225 	    sc->sc_control_data, sizeof(struct gem_control_data),
226 	    gem_cddma_callback, sc, 0)) != 0 || sc->sc_cddma == 0) {
227 		device_printf(sc->sc_dev,
228 		    "unable to load control data DMA map, error = %d\n",
229 		    error);
230 		goto fail_cmem;
231 	}
232 
233 	/*
234 	 * Initialize the transmit job descriptors.
235 	 */
236 	STAILQ_INIT(&sc->sc_txfreeq);
237 	STAILQ_INIT(&sc->sc_txdirtyq);
238 
239 	/*
240 	 * Create the transmit buffer DMA maps.
241 	 */
242 	error = ENOMEM;
243 	for (i = 0; i < GEM_TXQUEUELEN; i++) {
244 		txs = &sc->sc_txsoft[i];
245 		txs->txs_mbuf = NULL;
246 		txs->txs_ndescs = 0;
247 		if ((error = bus_dmamap_create(sc->sc_tdmatag, 0,
248 		    &txs->txs_dmamap)) != 0) {
249 			device_printf(sc->sc_dev,
250 			    "unable to create TX DMA map %d, error = %d\n",
251 			    i, error);
252 			goto fail_txd;
253 		}
254 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
255 	}
256 
257 	/*
258 	 * Create the receive buffer DMA maps.
259 	 */
260 	for (i = 0; i < GEM_NRXDESC; i++) {
261 		if ((error = bus_dmamap_create(sc->sc_rdmatag, 0,
262 		    &sc->sc_rxsoft[i].rxs_dmamap)) != 0) {
263 			device_printf(sc->sc_dev,
264 			    "unable to create RX DMA map %d, error = %d\n",
265 			    i, error);
266 			goto fail_rxd;
267 		}
268 		sc->sc_rxsoft[i].rxs_mbuf = NULL;
269 	}
270 
271 	/* Bypass probing PHYs if we already know for sure to use a SERDES. */
272 	if ((sc->sc_flags & GEM_SERDES) != 0)
273 		goto serdes;
274 
275 	/* Bad things will happen when touching this register on ERI. */
276 	if (sc->sc_variant != GEM_SUN_ERI) {
277 		GEM_BANK1_WRITE_4(sc, GEM_MII_DATAPATH_MODE,
278 		    GEM_MII_DATAPATH_MII);
279 		GEM_BANK1_BARRIER(sc, GEM_MII_DATAPATH_MODE, 4,
280 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
281 	}
282 
283 	gem_mifinit(sc);
284 
285 	/*
286 	 * Look for an external PHY.
287 	 */
288 	error = ENXIO;
289 	v = GEM_BANK1_READ_4(sc, GEM_MIF_CONFIG);
290 	if ((v & GEM_MIF_CONFIG_MDI1) != 0) {
291 		v |= GEM_MIF_CONFIG_PHY_SEL;
292 		GEM_BANK1_WRITE_4(sc, GEM_MIF_CONFIG, v);
293 		GEM_BANK1_BARRIER(sc, GEM_MIF_CONFIG, 4,
294 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
295 		switch (sc->sc_variant) {
296 		case GEM_SUN_ERI:
297 			phy = GEM_PHYAD_EXTERNAL;
298 			break;
299 		default:
300 			phy = MII_PHY_ANY;
301 			break;
302 		}
303 		error = mii_attach(sc->sc_dev, &sc->sc_miibus, ifp,
304 		    gem_mediachange, gem_mediastatus, BMSR_DEFCAPMASK, phy,
305 		    MII_OFFSET_ANY, 0);
306 	}
307 
308 	/*
309 	 * Fall back on an internal PHY if no external PHY was found.
310 	 * Note that with Apple (K2) GMACs GEM_MIF_CONFIG_MDI0 can't be
311 	 * trusted when the firmware has powered down the chip.
312 	 */
313 	if (error != 0 &&
314 	    ((v & GEM_MIF_CONFIG_MDI0) != 0 || GEM_IS_APPLE(sc))) {
315 		v &= ~GEM_MIF_CONFIG_PHY_SEL;
316 		GEM_BANK1_WRITE_4(sc, GEM_MIF_CONFIG, v);
317 		GEM_BANK1_BARRIER(sc, GEM_MIF_CONFIG, 4,
318 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
319 		switch (sc->sc_variant) {
320 		case GEM_SUN_ERI:
321 		case GEM_APPLE_K2_GMAC:
322 			phy = GEM_PHYAD_INTERNAL;
323 			break;
324 		case GEM_APPLE_GMAC:
325 			phy = GEM_PHYAD_EXTERNAL;
326 			break;
327 		default:
328 			phy = MII_PHY_ANY;
329 			break;
330 		}
331 		error = mii_attach(sc->sc_dev, &sc->sc_miibus, ifp,
332 		    gem_mediachange, gem_mediastatus, BMSR_DEFCAPMASK, phy,
333 		    MII_OFFSET_ANY, 0);
334 	}
335 
336 	/*
337 	 * Try the external PCS SERDES if we didn't find any PHYs.
338 	 */
339 	if (error != 0 && sc->sc_variant == GEM_SUN_GEM) {
340  serdes:
341 		GEM_BANK1_WRITE_4(sc, GEM_MII_DATAPATH_MODE,
342 		    GEM_MII_DATAPATH_SERDES);
343 		GEM_BANK1_BARRIER(sc, GEM_MII_DATAPATH_MODE, 4,
344 		    BUS_SPACE_BARRIER_WRITE);
345 		GEM_BANK1_WRITE_4(sc, GEM_MII_SLINK_CONTROL,
346 		    GEM_MII_SLINK_LOOPBACK | GEM_MII_SLINK_EN_SYNC_D);
347 		GEM_BANK1_BARRIER(sc, GEM_MII_SLINK_CONTROL, 4,
348 		    BUS_SPACE_BARRIER_WRITE);
349 		GEM_BANK1_WRITE_4(sc, GEM_MII_CONFIG, GEM_MII_CONFIG_ENABLE);
350 		GEM_BANK1_BARRIER(sc, GEM_MII_CONFIG, 4,
351 		    BUS_SPACE_BARRIER_WRITE);
352 		sc->sc_flags |= GEM_SERDES;
353 		error = mii_attach(sc->sc_dev, &sc->sc_miibus, ifp,
354 		    gem_mediachange, gem_mediastatus, BMSR_DEFCAPMASK,
355 		    GEM_PHYAD_EXTERNAL, MII_OFFSET_ANY, 0);
356 	}
357 	if (error != 0) {
358 		device_printf(sc->sc_dev, "attaching PHYs failed\n");
359 		goto fail_rxd;
360 	}
361 	sc->sc_mii = device_get_softc(sc->sc_miibus);
362 
363 	/*
364 	 * From this point forward, the attachment cannot fail.  A failure
365 	 * before this point releases all resources that may have been
366 	 * allocated.
367 	 */
368 
369 	/* Get RX FIFO size. */
370 	sc->sc_rxfifosize = 64 *
371 	    GEM_BANK1_READ_4(sc, GEM_RX_FIFO_SIZE);
372 
373 	/* Get TX FIFO size. */
374 	v = GEM_BANK1_READ_4(sc, GEM_TX_FIFO_SIZE);
375 	device_printf(sc->sc_dev, "%ukB RX FIFO, %ukB TX FIFO\n",
376 	    sc->sc_rxfifosize / 1024, v / 16);
377 
378 	/* Attach the interface. */
379 	ether_ifattach(ifp, sc->sc_enaddr);
380 
381 	/*
382 	 * Tell the upper layer(s) we support long frames/checksum offloads.
383 	 */
384 	ifp->if_data.ifi_hdrlen = sizeof(struct ether_vlan_header);
385 	ifp->if_capabilities |= IFCAP_VLAN_MTU | IFCAP_HWCSUM;
386 	ifp->if_hwassist |= sc->sc_csum_features;
387 	ifp->if_capenable |= IFCAP_VLAN_MTU | IFCAP_HWCSUM;
388 
389 	return (0);
390 
391 	/*
392 	 * Free any resources we've allocated during the failed attach
393 	 * attempt.  Do this in reverse order and fall through.
394 	 */
395  fail_rxd:
396 	for (i = 0; i < GEM_NRXDESC; i++)
397 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
398 			bus_dmamap_destroy(sc->sc_rdmatag,
399 			    sc->sc_rxsoft[i].rxs_dmamap);
400  fail_txd:
401 	for (i = 0; i < GEM_TXQUEUELEN; i++)
402 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
403 			bus_dmamap_destroy(sc->sc_tdmatag,
404 			    sc->sc_txsoft[i].txs_dmamap);
405 	bus_dmamap_unload(sc->sc_cdmatag, sc->sc_cddmamap);
406  fail_cmem:
407 	bus_dmamem_free(sc->sc_cdmatag, sc->sc_control_data,
408 	    sc->sc_cddmamap);
409  fail_ctag:
410 	bus_dma_tag_destroy(sc->sc_cdmatag);
411  fail_ttag:
412 	bus_dma_tag_destroy(sc->sc_tdmatag);
413  fail_rtag:
414 	bus_dma_tag_destroy(sc->sc_rdmatag);
415  fail_ptag:
416 	bus_dma_tag_destroy(sc->sc_pdmatag);
417  fail_ifnet:
418 	if_free(ifp);
419 	return (error);
420 }
421 
422 void
423 gem_detach(struct gem_softc *sc)
424 {
425 	struct ifnet *ifp = sc->sc_ifp;
426 	int i;
427 
428 	ether_ifdetach(ifp);
429 	GEM_LOCK(sc);
430 	gem_stop(ifp, 1);
431 	GEM_UNLOCK(sc);
432 	callout_drain(&sc->sc_tick_ch);
433 #ifdef GEM_RINT_TIMEOUT
434 	callout_drain(&sc->sc_rx_ch);
435 #endif
436 	if_free(ifp);
437 	device_delete_child(sc->sc_dev, sc->sc_miibus);
438 
439 	for (i = 0; i < GEM_NRXDESC; i++)
440 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
441 			bus_dmamap_destroy(sc->sc_rdmatag,
442 			    sc->sc_rxsoft[i].rxs_dmamap);
443 	for (i = 0; i < GEM_TXQUEUELEN; i++)
444 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
445 			bus_dmamap_destroy(sc->sc_tdmatag,
446 			    sc->sc_txsoft[i].txs_dmamap);
447 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
448 	bus_dmamap_unload(sc->sc_cdmatag, sc->sc_cddmamap);
449 	bus_dmamem_free(sc->sc_cdmatag, sc->sc_control_data,
450 	    sc->sc_cddmamap);
451 	bus_dma_tag_destroy(sc->sc_cdmatag);
452 	bus_dma_tag_destroy(sc->sc_tdmatag);
453 	bus_dma_tag_destroy(sc->sc_rdmatag);
454 	bus_dma_tag_destroy(sc->sc_pdmatag);
455 }
456 
457 void
458 gem_suspend(struct gem_softc *sc)
459 {
460 	struct ifnet *ifp = sc->sc_ifp;
461 
462 	GEM_LOCK(sc);
463 	gem_stop(ifp, 0);
464 	GEM_UNLOCK(sc);
465 }
466 
467 void
468 gem_resume(struct gem_softc *sc)
469 {
470 	struct ifnet *ifp = sc->sc_ifp;
471 
472 	GEM_LOCK(sc);
473 	/*
474 	 * On resume all registers have to be initialized again like
475 	 * after power-on.
476 	 */
477 	sc->sc_flags &= ~GEM_INITED;
478 	if (ifp->if_flags & IFF_UP)
479 		gem_init_locked(sc);
480 	GEM_UNLOCK(sc);
481 }
482 
483 static inline void
484 gem_rxcksum(struct mbuf *m, uint64_t flags)
485 {
486 	struct ether_header *eh;
487 	struct ip *ip;
488 	struct udphdr *uh;
489 	uint16_t *opts;
490 	int32_t hlen, len, pktlen;
491 	uint32_t temp32;
492 	uint16_t cksum;
493 
494 	pktlen = m->m_pkthdr.len;
495 	if (pktlen < sizeof(struct ether_header) + sizeof(struct ip))
496 		return;
497 	eh = mtod(m, struct ether_header *);
498 	if (eh->ether_type != htons(ETHERTYPE_IP))
499 		return;
500 	ip = (struct ip *)(eh + 1);
501 	if (ip->ip_v != IPVERSION)
502 		return;
503 
504 	hlen = ip->ip_hl << 2;
505 	pktlen -= sizeof(struct ether_header);
506 	if (hlen < sizeof(struct ip))
507 		return;
508 	if (ntohs(ip->ip_len) < hlen)
509 		return;
510 	if (ntohs(ip->ip_len) != pktlen)
511 		return;
512 	if (ip->ip_off & htons(IP_MF | IP_OFFMASK))
513 		return;	/* Cannot handle fragmented packet. */
514 
515 	switch (ip->ip_p) {
516 	case IPPROTO_TCP:
517 		if (pktlen < (hlen + sizeof(struct tcphdr)))
518 			return;
519 		break;
520 	case IPPROTO_UDP:
521 		if (pktlen < (hlen + sizeof(struct udphdr)))
522 			return;
523 		uh = (struct udphdr *)((uint8_t *)ip + hlen);
524 		if (uh->uh_sum == 0)
525 			return; /* no checksum */
526 		break;
527 	default:
528 		return;
529 	}
530 
531 	cksum = ~(flags & GEM_RD_CHECKSUM);
532 	/* checksum fixup for IP options */
533 	len = hlen - sizeof(struct ip);
534 	if (len > 0) {
535 		opts = (uint16_t *)(ip + 1);
536 		for (; len > 0; len -= sizeof(uint16_t), opts++) {
537 			temp32 = cksum - *opts;
538 			temp32 = (temp32 >> 16) + (temp32 & 65535);
539 			cksum = temp32 & 65535;
540 		}
541 	}
542 	m->m_pkthdr.csum_flags |= CSUM_DATA_VALID;
543 	m->m_pkthdr.csum_data = cksum;
544 }
545 
546 static void
547 gem_cddma_callback(void *xsc, bus_dma_segment_t *segs, int nsegs, int error)
548 {
549 	struct gem_softc *sc = xsc;
550 
551 	if (error != 0)
552 		return;
553 	if (nsegs != 1)
554 		panic("%s: bad control buffer segment count", __func__);
555 	sc->sc_cddma = segs[0].ds_addr;
556 }
557 
558 static void
559 gem_tick(void *arg)
560 {
561 	struct gem_softc *sc = arg;
562 	struct ifnet *ifp = sc->sc_ifp;
563 	uint32_t v;
564 
565 	GEM_LOCK_ASSERT(sc, MA_OWNED);
566 
567 	/*
568 	 * Unload collision and error counters.
569 	 */
570 	ifp->if_collisions +=
571 	    GEM_BANK1_READ_4(sc, GEM_MAC_NORM_COLL_CNT) +
572 	    GEM_BANK1_READ_4(sc, GEM_MAC_FIRST_COLL_CNT);
573 	v = GEM_BANK1_READ_4(sc, GEM_MAC_EXCESS_COLL_CNT) +
574 	    GEM_BANK1_READ_4(sc, GEM_MAC_LATE_COLL_CNT);
575 	ifp->if_collisions += v;
576 	ifp->if_oerrors += v;
577 	ifp->if_ierrors +=
578 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_LEN_ERR_CNT) +
579 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_ALIGN_ERR) +
580 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CRC_ERR_CNT) +
581 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CODE_VIOL);
582 
583 	/*
584 	 * Then clear the hardware counters.
585 	 */
586 	GEM_BANK1_WRITE_4(sc, GEM_MAC_NORM_COLL_CNT, 0);
587 	GEM_BANK1_WRITE_4(sc, GEM_MAC_FIRST_COLL_CNT, 0);
588 	GEM_BANK1_WRITE_4(sc, GEM_MAC_EXCESS_COLL_CNT, 0);
589 	GEM_BANK1_WRITE_4(sc, GEM_MAC_LATE_COLL_CNT, 0);
590 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_LEN_ERR_CNT, 0);
591 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_ALIGN_ERR, 0);
592 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CRC_ERR_CNT, 0);
593 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CODE_VIOL, 0);
594 
595 	mii_tick(sc->sc_mii);
596 
597 	if (gem_watchdog(sc) == EJUSTRETURN)
598 		return;
599 
600 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
601 }
602 
603 static int
604 gem_bitwait(struct gem_softc *sc, u_int bank, bus_addr_t r, uint32_t clr,
605     uint32_t set)
606 {
607 	int i;
608 	uint32_t reg;
609 
610 	for (i = GEM_TRIES; i--; DELAY(100)) {
611 		reg = GEM_BANKN_READ_M(bank, 4, sc, r);
612 		if ((reg & clr) == 0 && (reg & set) == set)
613 			return (1);
614 	}
615 	return (0);
616 }
617 
618 static void
619 gem_reset(struct gem_softc *sc)
620 {
621 
622 #ifdef GEM_DEBUG
623 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
624 #endif
625 	gem_reset_rx(sc);
626 	gem_reset_tx(sc);
627 
628 	/* Do a full reset. */
629 	GEM_BANK2_WRITE_4(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX);
630 	GEM_BANK2_BARRIER(sc, GEM_RESET, 4,
631 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
632 	if (!GEM_BANK2_BITWAIT(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX, 0))
633 		device_printf(sc->sc_dev, "cannot reset device\n");
634 }
635 
636 static void
637 gem_rxdrain(struct gem_softc *sc)
638 {
639 	struct gem_rxsoft *rxs;
640 	int i;
641 
642 	for (i = 0; i < GEM_NRXDESC; i++) {
643 		rxs = &sc->sc_rxsoft[i];
644 		if (rxs->rxs_mbuf != NULL) {
645 			bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
646 			    BUS_DMASYNC_POSTREAD);
647 			bus_dmamap_unload(sc->sc_rdmatag, rxs->rxs_dmamap);
648 			m_freem(rxs->rxs_mbuf);
649 			rxs->rxs_mbuf = NULL;
650 		}
651 	}
652 }
653 
654 static void
655 gem_stop(struct ifnet *ifp, int disable)
656 {
657 	struct gem_softc *sc = ifp->if_softc;
658 	struct gem_txsoft *txs;
659 
660 #ifdef GEM_DEBUG
661 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
662 #endif
663 
664 	callout_stop(&sc->sc_tick_ch);
665 #ifdef GEM_RINT_TIMEOUT
666 	callout_stop(&sc->sc_rx_ch);
667 #endif
668 
669 	gem_reset_tx(sc);
670 	gem_reset_rx(sc);
671 
672 	/*
673 	 * Release any queued transmit buffers.
674 	 */
675 	while ((txs = STAILQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
676 		STAILQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
677 		if (txs->txs_ndescs != 0) {
678 			bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
679 			    BUS_DMASYNC_POSTWRITE);
680 			bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
681 			if (txs->txs_mbuf != NULL) {
682 				m_freem(txs->txs_mbuf);
683 				txs->txs_mbuf = NULL;
684 			}
685 		}
686 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
687 	}
688 
689 	if (disable)
690 		gem_rxdrain(sc);
691 
692 	/*
693 	 * Mark the interface down and cancel the watchdog timer.
694 	 */
695 	ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
696 	sc->sc_flags &= ~GEM_LINK;
697 	sc->sc_wdog_timer = 0;
698 }
699 
700 static int
701 gem_reset_rx(struct gem_softc *sc)
702 {
703 
704 	/*
705 	 * Resetting while DMA is in progress can cause a bus hang, so we
706 	 * disable DMA first.
707 	 */
708 	gem_disable_rx(sc);
709 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG, 0);
710 	GEM_BANK1_BARRIER(sc, GEM_RX_CONFIG, 4,
711 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
712 	if (!GEM_BANK1_BITWAIT(sc, GEM_RX_CONFIG, GEM_RX_CONFIG_RXDMA_EN, 0))
713 		device_printf(sc->sc_dev, "cannot disable RX DMA\n");
714 
715 	/* Finally, reset the ERX. */
716 	GEM_BANK2_WRITE_4(sc, GEM_RESET, GEM_RESET_RX);
717 	GEM_BANK2_BARRIER(sc, GEM_RESET, 4,
718 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
719 	if (!GEM_BANK2_BITWAIT(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX,
720 	    0)) {
721 		device_printf(sc->sc_dev, "cannot reset receiver\n");
722 		return (1);
723 	}
724 	return (0);
725 }
726 
727 /*
728  * Reset the receiver DMA engine.
729  *
730  * Intended to be used in case of GEM_INTR_RX_TAG_ERR, GEM_MAC_RX_OVERFLOW
731  * etc in order to reset the receiver DMA engine only and not do a full
732  * reset which amongst others also downs the link and clears the FIFOs.
733  */
734 static void
735 gem_reset_rxdma(struct gem_softc *sc)
736 {
737 	int i;
738 
739 	if (gem_reset_rx(sc) != 0)
740 		return (gem_init_locked(sc));
741 	for (i = 0; i < GEM_NRXDESC; i++)
742 		if (sc->sc_rxsoft[i].rxs_mbuf != NULL)
743 			GEM_UPDATE_RXDESC(sc, i);
744 	sc->sc_rxptr = 0;
745 	GEM_CDSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
746 
747 	/* NOTE: we use only 32-bit DMA addresses here. */
748 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_HI, 0);
749 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_LO, GEM_CDRXADDR(sc, 0));
750 	GEM_BANK1_WRITE_4(sc, GEM_RX_KICK, GEM_NRXDESC - 4);
751 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG,
752 	    gem_ringsize(GEM_NRXDESC /* XXX */) |
753 	    ((ETHER_HDR_LEN + sizeof(struct ip)) <<
754 	    GEM_RX_CONFIG_CXM_START_SHFT) |
755 	    (GEM_THRSH_1024 << GEM_RX_CONFIG_FIFO_THRS_SHIFT) |
756 	    (ETHER_ALIGN << GEM_RX_CONFIG_FBOFF_SHFT));
757 	/* Adjust for the SBus clock probably isn't worth the fuzz. */
758 	GEM_BANK1_WRITE_4(sc, GEM_RX_BLANKING,
759 	    ((6 * (sc->sc_flags & GEM_PCI66) != 0 ? 2 : 1) <<
760 	    GEM_RX_BLANKING_TIME_SHIFT) | 6);
761 	GEM_BANK1_WRITE_4(sc, GEM_RX_PAUSE_THRESH,
762 	    (3 * sc->sc_rxfifosize / 256) |
763 	    ((sc->sc_rxfifosize / 256) << 12));
764 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG,
765 	    GEM_BANK1_READ_4(sc, GEM_RX_CONFIG) | GEM_RX_CONFIG_RXDMA_EN);
766 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_MASK,
767 	    GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT);
768 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG,
769 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG) | GEM_MAC_RX_ENABLE);
770 }
771 
772 static int
773 gem_reset_tx(struct gem_softc *sc)
774 {
775 
776 	/*
777 	 * Resetting while DMA is in progress can cause a bus hang, so we
778 	 * disable DMA first.
779 	 */
780 	gem_disable_tx(sc);
781 	GEM_BANK1_WRITE_4(sc, GEM_TX_CONFIG, 0);
782 	GEM_BANK1_BARRIER(sc, GEM_TX_CONFIG, 4,
783 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
784 	if (!GEM_BANK1_BITWAIT(sc, GEM_TX_CONFIG, GEM_TX_CONFIG_TXDMA_EN, 0))
785 		device_printf(sc->sc_dev, "cannot disable TX DMA\n");
786 
787 	/* Finally, reset the ETX. */
788 	GEM_BANK2_WRITE_4(sc, GEM_RESET, GEM_RESET_TX);
789 	GEM_BANK2_BARRIER(sc, GEM_RESET, 4,
790 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
791 	if (!GEM_BANK2_BITWAIT(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX,
792 	    0)) {
793 		device_printf(sc->sc_dev, "cannot reset transmitter\n");
794 		return (1);
795 	}
796 	return (0);
797 }
798 
799 static int
800 gem_disable_rx(struct gem_softc *sc)
801 {
802 
803 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG,
804 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG) & ~GEM_MAC_RX_ENABLE);
805 	GEM_BANK1_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
806 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
807 	return (GEM_BANK1_BITWAIT(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_ENABLE,
808 	    0));
809 }
810 
811 static int
812 gem_disable_tx(struct gem_softc *sc)
813 {
814 
815 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG,
816 	    GEM_BANK1_READ_4(sc, GEM_MAC_TX_CONFIG) & ~GEM_MAC_TX_ENABLE);
817 	GEM_BANK1_BARRIER(sc, GEM_MAC_TX_CONFIG, 4,
818 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
819 	return (GEM_BANK1_BITWAIT(sc, GEM_MAC_TX_CONFIG, GEM_MAC_TX_ENABLE,
820 	    0));
821 }
822 
823 static int
824 gem_meminit(struct gem_softc *sc)
825 {
826 	struct gem_rxsoft *rxs;
827 	int error, i;
828 
829 	GEM_LOCK_ASSERT(sc, MA_OWNED);
830 
831 	/*
832 	 * Initialize the transmit descriptor ring.
833 	 */
834 	for (i = 0; i < GEM_NTXDESC; i++) {
835 		sc->sc_txdescs[i].gd_flags = 0;
836 		sc->sc_txdescs[i].gd_addr = 0;
837 	}
838 	sc->sc_txfree = GEM_MAXTXFREE;
839 	sc->sc_txnext = 0;
840 	sc->sc_txwin = 0;
841 
842 	/*
843 	 * Initialize the receive descriptor and receive job
844 	 * descriptor rings.
845 	 */
846 	for (i = 0; i < GEM_NRXDESC; i++) {
847 		rxs = &sc->sc_rxsoft[i];
848 		if (rxs->rxs_mbuf == NULL) {
849 			if ((error = gem_add_rxbuf(sc, i)) != 0) {
850 				device_printf(sc->sc_dev,
851 				    "unable to allocate or map RX buffer %d, "
852 				    "error = %d\n", i, error);
853 				/*
854 				 * XXX we should attempt to run with fewer
855 				 * receive buffers instead of just failing.
856 				 */
857 				gem_rxdrain(sc);
858 				return (1);
859 			}
860 		} else
861 			GEM_INIT_RXDESC(sc, i);
862 	}
863 	sc->sc_rxptr = 0;
864 
865 	GEM_CDSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
866 
867 	return (0);
868 }
869 
870 static u_int
871 gem_ringsize(u_int sz)
872 {
873 
874 	switch (sz) {
875 	case 32:
876 		return (GEM_RING_SZ_32);
877 	case 64:
878 		return (GEM_RING_SZ_64);
879 	case 128:
880 		return (GEM_RING_SZ_128);
881 	case 256:
882 		return (GEM_RING_SZ_256);
883 	case 512:
884 		return (GEM_RING_SZ_512);
885 	case 1024:
886 		return (GEM_RING_SZ_1024);
887 	case 2048:
888 		return (GEM_RING_SZ_2048);
889 	case 4096:
890 		return (GEM_RING_SZ_4096);
891 	case 8192:
892 		return (GEM_RING_SZ_8192);
893 	default:
894 		printf("%s: invalid ring size %d\n", __func__, sz);
895 		return (GEM_RING_SZ_32);
896 	}
897 }
898 
899 static void
900 gem_init(void *xsc)
901 {
902 	struct gem_softc *sc = xsc;
903 
904 	GEM_LOCK(sc);
905 	gem_init_locked(sc);
906 	GEM_UNLOCK(sc);
907 }
908 
909 /*
910  * Initialization of interface; set up initialization block
911  * and transmit/receive descriptor rings.
912  */
913 static void
914 gem_init_locked(struct gem_softc *sc)
915 {
916 	struct ifnet *ifp = sc->sc_ifp;
917 	uint32_t v;
918 
919 	GEM_LOCK_ASSERT(sc, MA_OWNED);
920 
921 #ifdef GEM_DEBUG
922 	CTR2(KTR_GEM, "%s: %s: calling stop", device_get_name(sc->sc_dev),
923 	    __func__);
924 #endif
925 	/*
926 	 * Initialization sequence.  The numbered steps below correspond
927 	 * to the sequence outlined in section 6.3.5.1 in the Ethernet
928 	 * Channel Engine manual (part of the PCIO manual).
929 	 * See also the STP2002-STQ document from Sun Microsystems.
930 	 */
931 
932 	/* step 1 & 2.  Reset the Ethernet Channel. */
933 	gem_stop(ifp, 0);
934 	gem_reset(sc);
935 #ifdef GEM_DEBUG
936 	CTR2(KTR_GEM, "%s: %s: restarting", device_get_name(sc->sc_dev),
937 	    __func__);
938 #endif
939 
940 	if ((sc->sc_flags & GEM_SERDES) == 0)
941 		/* Re-initialize the MIF. */
942 		gem_mifinit(sc);
943 
944 	/* step 3.  Setup data structures in host memory. */
945 	if (gem_meminit(sc) != 0)
946 		return;
947 
948 	/* step 4.  TX MAC registers & counters */
949 	gem_init_regs(sc);
950 
951 	/* step 5.  RX MAC registers & counters */
952 	gem_setladrf(sc);
953 
954 	/* step 6 & 7.  Program Descriptor Ring Base Addresses. */
955 	/* NOTE: we use only 32-bit DMA addresses here. */
956 	GEM_BANK1_WRITE_4(sc, GEM_TX_RING_PTR_HI, 0);
957 	GEM_BANK1_WRITE_4(sc, GEM_TX_RING_PTR_LO, GEM_CDTXADDR(sc, 0));
958 
959 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_HI, 0);
960 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_LO, GEM_CDRXADDR(sc, 0));
961 #ifdef GEM_DEBUG
962 	CTR3(KTR_GEM, "loading RX ring %lx, TX ring %lx, cddma %lx",
963 	    GEM_CDRXADDR(sc, 0), GEM_CDTXADDR(sc, 0), sc->sc_cddma);
964 #endif
965 
966 	/* step 8.  Global Configuration & Interrupt Mask */
967 
968 	/*
969 	 * Set the internal arbitration to "infinite" bursts of the
970 	 * maximum length of 31 * 64 bytes so DMA transfers aren't
971 	 * split up in cache line size chunks.  This greatly improves
972 	 * RX performance.
973 	 * Enable silicon bug workarounds for the Apple variants.
974 	 */
975 	GEM_BANK1_WRITE_4(sc, GEM_CONFIG,
976 	    GEM_CONFIG_TXDMA_LIMIT | GEM_CONFIG_RXDMA_LIMIT |
977 	    ((sc->sc_flags & GEM_PCI) != 0 ? GEM_CONFIG_BURST_INF :
978 	    GEM_CONFIG_BURST_64) | (GEM_IS_APPLE(sc) ?
979 	    GEM_CONFIG_RONPAULBIT | GEM_CONFIG_BUG2FIX : 0));
980 
981 	GEM_BANK1_WRITE_4(sc, GEM_INTMASK,
982 	    ~(GEM_INTR_TX_INTME | GEM_INTR_TX_EMPTY | GEM_INTR_RX_DONE |
983 	    GEM_INTR_RX_NOBUF | GEM_INTR_RX_TAG_ERR | GEM_INTR_PERR |
984 	    GEM_INTR_BERR
985 #ifdef GEM_DEBUG
986 	    | GEM_INTR_PCS | GEM_INTR_MIF
987 #endif
988 	    ));
989 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_MASK,
990 	    GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT);
991 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_MASK,
992 	    GEM_MAC_TX_XMIT_DONE | GEM_MAC_TX_DEFER_EXP |
993 	    GEM_MAC_TX_PEAK_EXP);
994 #ifdef GEM_DEBUG
995 	GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_MASK,
996 	    ~(GEM_MAC_PAUSED | GEM_MAC_PAUSE | GEM_MAC_RESUME));
997 #else
998 	GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_MASK,
999 	    GEM_MAC_PAUSED | GEM_MAC_PAUSE | GEM_MAC_RESUME);
1000 #endif
1001 
1002 	/* step 9.  ETX Configuration: use mostly default values. */
1003 
1004 	/* Enable DMA. */
1005 	v = gem_ringsize(GEM_NTXDESC);
1006 	/* Set TX FIFO threshold and enable DMA. */
1007 	v |= ((sc->sc_variant == GEM_SUN_ERI ? 0x100 : 0x4ff) << 10) &
1008 	    GEM_TX_CONFIG_TXFIFO_TH;
1009 	GEM_BANK1_WRITE_4(sc, GEM_TX_CONFIG, v | GEM_TX_CONFIG_TXDMA_EN);
1010 
1011 	/* step 10.  ERX Configuration */
1012 
1013 	/* Encode Receive Descriptor ring size. */
1014 	v = gem_ringsize(GEM_NRXDESC /* XXX */);
1015 	/* RX TCP/UDP checksum offset */
1016 	v |= ((ETHER_HDR_LEN + sizeof(struct ip)) <<
1017 	    GEM_RX_CONFIG_CXM_START_SHFT);
1018 	/* Set RX FIFO threshold, set first byte offset and enable DMA. */
1019 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG,
1020 	    v | (GEM_THRSH_1024 << GEM_RX_CONFIG_FIFO_THRS_SHIFT) |
1021 	    (ETHER_ALIGN << GEM_RX_CONFIG_FBOFF_SHFT) |
1022 	    GEM_RX_CONFIG_RXDMA_EN);
1023 
1024 	/* Adjust for the SBus clock probably isn't worth the fuzz. */
1025 	GEM_BANK1_WRITE_4(sc, GEM_RX_BLANKING,
1026 	    ((6 * (sc->sc_flags & GEM_PCI66) != 0 ? 2 : 1) <<
1027 	    GEM_RX_BLANKING_TIME_SHIFT) | 6);
1028 
1029 	/*
1030 	 * The following value is for an OFF Threshold of about 3/4 full
1031 	 * and an ON Threshold of 1/4 full.
1032 	 */
1033 	GEM_BANK1_WRITE_4(sc, GEM_RX_PAUSE_THRESH,
1034 	    (3 * sc->sc_rxfifosize / 256) |
1035 	    ((sc->sc_rxfifosize / 256) << 12));
1036 
1037 	/* step 11.  Configure Media. */
1038 
1039 	/* step 12.  RX_MAC Configuration Register */
1040 	v = GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG);
1041 	v |= GEM_MAC_RX_ENABLE | GEM_MAC_RX_STRIP_CRC;
1042 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, 0);
1043 	GEM_BANK1_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
1044 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1045 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_ENABLE, 0))
1046 		device_printf(sc->sc_dev, "cannot configure RX MAC\n");
1047 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, v);
1048 
1049 	/* step 13.  TX_MAC Configuration Register */
1050 	v = GEM_BANK1_READ_4(sc, GEM_MAC_TX_CONFIG);
1051 	v |= GEM_MAC_TX_ENABLE;
1052 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG, 0);
1053 	GEM_BANK1_BARRIER(sc, GEM_MAC_TX_CONFIG, 4,
1054 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1055 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_TX_CONFIG, GEM_MAC_TX_ENABLE, 0))
1056 		device_printf(sc->sc_dev, "cannot configure TX MAC\n");
1057 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG, v);
1058 
1059 	/* step 14.  Issue Transmit Pending command. */
1060 
1061 	/* step 15.  Give the reciever a swift kick. */
1062 	GEM_BANK1_WRITE_4(sc, GEM_RX_KICK, GEM_NRXDESC - 4);
1063 
1064 	ifp->if_drv_flags |= IFF_DRV_RUNNING;
1065 	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
1066 
1067 	mii_mediachg(sc->sc_mii);
1068 
1069 	/* Start the one second timer. */
1070 	sc->sc_wdog_timer = 0;
1071 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
1072 }
1073 
1074 static int
1075 gem_load_txmbuf(struct gem_softc *sc, struct mbuf **m_head)
1076 {
1077 	bus_dma_segment_t txsegs[GEM_NTXSEGS];
1078 	struct gem_txsoft *txs;
1079 	struct ip *ip;
1080 	struct mbuf *m;
1081 	uint64_t cflags, flags;
1082 	int error, nexttx, nsegs, offset, seg;
1083 
1084 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1085 
1086 	/* Get a work queue entry. */
1087 	if ((txs = STAILQ_FIRST(&sc->sc_txfreeq)) == NULL) {
1088 		/* Ran out of descriptors. */
1089 		return (ENOBUFS);
1090 	}
1091 
1092 	cflags = 0;
1093 	if (((*m_head)->m_pkthdr.csum_flags & sc->sc_csum_features) != 0) {
1094 		if (M_WRITABLE(*m_head) == 0) {
1095 			m = m_dup(*m_head, M_DONTWAIT);
1096 			m_freem(*m_head);
1097 			*m_head = m;
1098 			if (m == NULL)
1099 				return (ENOBUFS);
1100 		}
1101 		offset = sizeof(struct ether_header);
1102 		m = m_pullup(*m_head, offset + sizeof(struct ip));
1103 		if (m == NULL) {
1104 			*m_head = NULL;
1105 			return (ENOBUFS);
1106 		}
1107 		ip = (struct ip *)(mtod(m, caddr_t) + offset);
1108 		offset += (ip->ip_hl << 2);
1109 		cflags = offset << GEM_TD_CXSUM_STARTSHFT |
1110 		    ((offset + m->m_pkthdr.csum_data) <<
1111 		    GEM_TD_CXSUM_STUFFSHFT) | GEM_TD_CXSUM_ENABLE;
1112 		*m_head = m;
1113 	}
1114 
1115 	error = bus_dmamap_load_mbuf_sg(sc->sc_tdmatag, txs->txs_dmamap,
1116 	    *m_head, txsegs, &nsegs, BUS_DMA_NOWAIT);
1117 	if (error == EFBIG) {
1118 		m = m_collapse(*m_head, M_DONTWAIT, GEM_NTXSEGS);
1119 		if (m == NULL) {
1120 			m_freem(*m_head);
1121 			*m_head = NULL;
1122 			return (ENOBUFS);
1123 		}
1124 		*m_head = m;
1125 		error = bus_dmamap_load_mbuf_sg(sc->sc_tdmatag,
1126 		    txs->txs_dmamap, *m_head, txsegs, &nsegs,
1127 		    BUS_DMA_NOWAIT);
1128 		if (error != 0) {
1129 			m_freem(*m_head);
1130 			*m_head = NULL;
1131 			return (error);
1132 		}
1133 	} else if (error != 0)
1134 		return (error);
1135 	/* If nsegs is wrong then the stack is corrupt. */
1136 	KASSERT(nsegs <= GEM_NTXSEGS,
1137 	    ("%s: too many DMA segments (%d)", __func__, nsegs));
1138 	if (nsegs == 0) {
1139 		m_freem(*m_head);
1140 		*m_head = NULL;
1141 		return (EIO);
1142 	}
1143 
1144 	/*
1145 	 * Ensure we have enough descriptors free to describe
1146 	 * the packet.  Note, we always reserve one descriptor
1147 	 * at the end of the ring as a termination point, in
1148 	 * order to prevent wrap-around.
1149 	 */
1150 	if (nsegs > sc->sc_txfree - 1) {
1151 		txs->txs_ndescs = 0;
1152 		bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
1153 		return (ENOBUFS);
1154 	}
1155 
1156 	txs->txs_ndescs = nsegs;
1157 	txs->txs_firstdesc = sc->sc_txnext;
1158 	nexttx = txs->txs_firstdesc;
1159 	for (seg = 0; seg < nsegs; seg++, nexttx = GEM_NEXTTX(nexttx)) {
1160 #ifdef GEM_DEBUG
1161 		CTR6(KTR_GEM,
1162 		    "%s: mapping seg %d (txd %d), len %lx, addr %#lx (%#lx)",
1163 		    __func__, seg, nexttx, txsegs[seg].ds_len,
1164 		    txsegs[seg].ds_addr,
1165 		    GEM_DMA_WRITE(sc, txsegs[seg].ds_addr));
1166 #endif
1167 		sc->sc_txdescs[nexttx].gd_addr =
1168 		    GEM_DMA_WRITE(sc, txsegs[seg].ds_addr);
1169 		KASSERT(txsegs[seg].ds_len < GEM_TD_BUFSIZE,
1170 		    ("%s: segment size too large!", __func__));
1171 		flags = txsegs[seg].ds_len & GEM_TD_BUFSIZE;
1172 		sc->sc_txdescs[nexttx].gd_flags =
1173 		    GEM_DMA_WRITE(sc, flags | cflags);
1174 		txs->txs_lastdesc = nexttx;
1175 	}
1176 
1177 	/* Set EOP on the last descriptor. */
1178 #ifdef GEM_DEBUG
1179 	CTR3(KTR_GEM, "%s: end of packet at segment %d, TX %d",
1180 	    __func__, seg, nexttx);
1181 #endif
1182 	sc->sc_txdescs[txs->txs_lastdesc].gd_flags |=
1183 	    GEM_DMA_WRITE(sc, GEM_TD_END_OF_PACKET);
1184 
1185 	/* Lastly set SOP on the first descriptor. */
1186 #ifdef GEM_DEBUG
1187 	CTR3(KTR_GEM, "%s: start of packet at segment %d, TX %d",
1188 	    __func__, seg, nexttx);
1189 #endif
1190 	if (++sc->sc_txwin > GEM_NTXSEGS * 2 / 3) {
1191 		sc->sc_txwin = 0;
1192 		sc->sc_txdescs[txs->txs_firstdesc].gd_flags |=
1193 		    GEM_DMA_WRITE(sc, GEM_TD_INTERRUPT_ME |
1194 		    GEM_TD_START_OF_PACKET);
1195 	} else
1196 		sc->sc_txdescs[txs->txs_firstdesc].gd_flags |=
1197 		    GEM_DMA_WRITE(sc, GEM_TD_START_OF_PACKET);
1198 
1199 	/* Sync the DMA map. */
1200 	bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
1201 	    BUS_DMASYNC_PREWRITE);
1202 
1203 #ifdef GEM_DEBUG
1204 	CTR4(KTR_GEM, "%s: setting firstdesc=%d, lastdesc=%d, ndescs=%d",
1205 	    __func__, txs->txs_firstdesc, txs->txs_lastdesc,
1206 	    txs->txs_ndescs);
1207 #endif
1208 	STAILQ_REMOVE_HEAD(&sc->sc_txfreeq, txs_q);
1209 	STAILQ_INSERT_TAIL(&sc->sc_txdirtyq, txs, txs_q);
1210 	txs->txs_mbuf = *m_head;
1211 
1212 	sc->sc_txnext = GEM_NEXTTX(txs->txs_lastdesc);
1213 	sc->sc_txfree -= txs->txs_ndescs;
1214 
1215 	return (0);
1216 }
1217 
1218 static void
1219 gem_init_regs(struct gem_softc *sc)
1220 {
1221 	const u_char *laddr = IF_LLADDR(sc->sc_ifp);
1222 
1223 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1224 
1225 	/* These registers are not cleared on reset. */
1226 	if ((sc->sc_flags & GEM_INITED) == 0) {
1227 		/* magic values */
1228 		GEM_BANK1_WRITE_4(sc, GEM_MAC_IPG0, 0);
1229 		GEM_BANK1_WRITE_4(sc, GEM_MAC_IPG1, 8);
1230 		GEM_BANK1_WRITE_4(sc, GEM_MAC_IPG2, 4);
1231 
1232 		/* min frame length */
1233 		GEM_BANK1_WRITE_4(sc, GEM_MAC_MAC_MIN_FRAME, ETHER_MIN_LEN);
1234 		/* max frame length and max burst size */
1235 		GEM_BANK1_WRITE_4(sc, GEM_MAC_MAC_MAX_FRAME,
1236 		    (ETHER_MAX_LEN + ETHER_VLAN_ENCAP_LEN) | (0x2000 << 16));
1237 
1238 		/* more magic values */
1239 		GEM_BANK1_WRITE_4(sc, GEM_MAC_PREAMBLE_LEN, 0x7);
1240 		GEM_BANK1_WRITE_4(sc, GEM_MAC_JAM_SIZE, 0x4);
1241 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ATTEMPT_LIMIT, 0x10);
1242 		GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_TYPE, 0x8088);
1243 
1244 		/* random number seed */
1245 		GEM_BANK1_WRITE_4(sc, GEM_MAC_RANDOM_SEED,
1246 		    ((laddr[5] << 8) | laddr[4]) & 0x3ff);
1247 
1248 		/* secondary MAC address: 0:0:0:0:0:0 */
1249 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR3, 0);
1250 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR4, 0);
1251 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR5, 0);
1252 
1253 		/* MAC control address: 01:80:c2:00:00:01 */
1254 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR6, 0x0001);
1255 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR7, 0xc200);
1256 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR8, 0x0180);
1257 
1258 		/* MAC filter address: 0:0:0:0:0:0 */
1259 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR_FILTER0, 0);
1260 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR_FILTER1, 0);
1261 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR_FILTER2, 0);
1262 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADR_FLT_MASK1_2, 0);
1263 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADR_FLT_MASK0, 0);
1264 
1265 		sc->sc_flags |= GEM_INITED;
1266 	}
1267 
1268 	/* Counters need to be zeroed. */
1269 	GEM_BANK1_WRITE_4(sc, GEM_MAC_NORM_COLL_CNT, 0);
1270 	GEM_BANK1_WRITE_4(sc, GEM_MAC_FIRST_COLL_CNT, 0);
1271 	GEM_BANK1_WRITE_4(sc, GEM_MAC_EXCESS_COLL_CNT, 0);
1272 	GEM_BANK1_WRITE_4(sc, GEM_MAC_LATE_COLL_CNT, 0);
1273 	GEM_BANK1_WRITE_4(sc, GEM_MAC_DEFER_TMR_CNT, 0);
1274 	GEM_BANK1_WRITE_4(sc, GEM_MAC_PEAK_ATTEMPTS, 0);
1275 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_FRAME_COUNT, 0);
1276 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_LEN_ERR_CNT, 0);
1277 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_ALIGN_ERR, 0);
1278 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CRC_ERR_CNT, 0);
1279 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CODE_VIOL, 0);
1280 
1281 	/* Set XOFF PAUSE time. */
1282 	GEM_BANK1_WRITE_4(sc, GEM_MAC_SEND_PAUSE_CMD, 0x1BF0);
1283 
1284 	/* Set the station address. */
1285 	GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR0, (laddr[4] << 8) | laddr[5]);
1286 	GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR1, (laddr[2] << 8) | laddr[3]);
1287 	GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR2, (laddr[0] << 8) | laddr[1]);
1288 
1289 	/* Enable MII outputs. */
1290 	GEM_BANK1_WRITE_4(sc, GEM_MAC_XIF_CONFIG, GEM_MAC_XIF_TX_MII_ENA);
1291 }
1292 
1293 static void
1294 gem_start(struct ifnet *ifp)
1295 {
1296 	struct gem_softc *sc = ifp->if_softc;
1297 
1298 	GEM_LOCK(sc);
1299 	gem_start_locked(ifp);
1300 	GEM_UNLOCK(sc);
1301 }
1302 
1303 static inline void
1304 gem_txkick(struct gem_softc *sc)
1305 {
1306 
1307 	/*
1308 	 * Update the TX kick register.  This register has to point to the
1309 	 * descriptor after the last valid one and for optimum performance
1310 	 * should be incremented in multiples of 4 (the DMA engine fetches/
1311 	 * updates descriptors in batches of 4).
1312 	 */
1313 #ifdef GEM_DEBUG
1314 	CTR3(KTR_GEM, "%s: %s: kicking TX %d",
1315 	    device_get_name(sc->sc_dev), __func__, sc->sc_txnext);
1316 #endif
1317 	GEM_CDSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1318 	GEM_BANK1_WRITE_4(sc, GEM_TX_KICK, sc->sc_txnext);
1319 }
1320 
1321 static void
1322 gem_start_locked(struct ifnet *ifp)
1323 {
1324 	struct gem_softc *sc = ifp->if_softc;
1325 	struct mbuf *m;
1326 	int kicked, ntx;
1327 
1328 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1329 
1330 	if ((ifp->if_drv_flags & (IFF_DRV_RUNNING | IFF_DRV_OACTIVE)) !=
1331 	    IFF_DRV_RUNNING || (sc->sc_flags & GEM_LINK) == 0)
1332 		return;
1333 
1334 #ifdef GEM_DEBUG
1335 	CTR4(KTR_GEM, "%s: %s: txfree %d, txnext %d",
1336 	    device_get_name(sc->sc_dev), __func__, sc->sc_txfree,
1337 	    sc->sc_txnext);
1338 #endif
1339 	ntx = 0;
1340 	kicked = 0;
1341 	for (; !IFQ_DRV_IS_EMPTY(&ifp->if_snd) && sc->sc_txfree > 1;) {
1342 		IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
1343 		if (m == NULL)
1344 			break;
1345 		if (gem_load_txmbuf(sc, &m) != 0) {
1346 			if (m == NULL)
1347 				break;
1348 			ifp->if_drv_flags |= IFF_DRV_OACTIVE;
1349 			IFQ_DRV_PREPEND(&ifp->if_snd, m);
1350 			break;
1351 		}
1352 		if ((sc->sc_txnext % 4) == 0) {
1353 			gem_txkick(sc);
1354 			kicked = 1;
1355 		} else
1356 			kicked = 0;
1357 		ntx++;
1358 		BPF_MTAP(ifp, m);
1359 	}
1360 
1361 	if (ntx > 0) {
1362 		if (kicked == 0)
1363 			gem_txkick(sc);
1364 #ifdef GEM_DEBUG
1365 		CTR2(KTR_GEM, "%s: packets enqueued, OWN on %d",
1366 		    device_get_name(sc->sc_dev), sc->sc_txnext);
1367 #endif
1368 
1369 		/* Set a watchdog timer in case the chip flakes out. */
1370 		sc->sc_wdog_timer = 5;
1371 #ifdef GEM_DEBUG
1372 		CTR3(KTR_GEM, "%s: %s: watchdog %d",
1373 		    device_get_name(sc->sc_dev), __func__,
1374 		    sc->sc_wdog_timer);
1375 #endif
1376 	}
1377 }
1378 
1379 static void
1380 gem_tint(struct gem_softc *sc)
1381 {
1382 	struct ifnet *ifp = sc->sc_ifp;
1383 	struct gem_txsoft *txs;
1384 	int progress;
1385 	uint32_t txlast;
1386 #ifdef GEM_DEBUG
1387 	int i;
1388 
1389 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1390 
1391 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
1392 #endif
1393 
1394 	/*
1395 	 * Go through our TX list and free mbufs for those
1396 	 * frames that have been transmitted.
1397 	 */
1398 	progress = 0;
1399 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD);
1400 	while ((txs = STAILQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
1401 #ifdef GEM_DEBUG
1402 		if ((ifp->if_flags & IFF_DEBUG) != 0) {
1403 			printf("    txsoft %p transmit chain:\n", txs);
1404 			for (i = txs->txs_firstdesc;; i = GEM_NEXTTX(i)) {
1405 				printf("descriptor %d: ", i);
1406 				printf("gd_flags: 0x%016llx\t",
1407 				    (long long)GEM_DMA_READ(sc,
1408 				    sc->sc_txdescs[i].gd_flags));
1409 				printf("gd_addr: 0x%016llx\n",
1410 				    (long long)GEM_DMA_READ(sc,
1411 				    sc->sc_txdescs[i].gd_addr));
1412 				if (i == txs->txs_lastdesc)
1413 					break;
1414 			}
1415 		}
1416 #endif
1417 
1418 		/*
1419 		 * In theory, we could harvest some descriptors before
1420 		 * the ring is empty, but that's a bit complicated.
1421 		 *
1422 		 * GEM_TX_COMPLETION points to the last descriptor
1423 		 * processed + 1.
1424 		 */
1425 		txlast = GEM_BANK1_READ_4(sc, GEM_TX_COMPLETION);
1426 #ifdef GEM_DEBUG
1427 		CTR4(KTR_GEM, "%s: txs->txs_firstdesc = %d, "
1428 		    "txs->txs_lastdesc = %d, txlast = %d",
1429 		    __func__, txs->txs_firstdesc, txs->txs_lastdesc, txlast);
1430 #endif
1431 		if (txs->txs_firstdesc <= txs->txs_lastdesc) {
1432 			if ((txlast >= txs->txs_firstdesc) &&
1433 			    (txlast <= txs->txs_lastdesc))
1434 				break;
1435 		} else {
1436 			/* Ick -- this command wraps. */
1437 			if ((txlast >= txs->txs_firstdesc) ||
1438 			    (txlast <= txs->txs_lastdesc))
1439 				break;
1440 		}
1441 
1442 #ifdef GEM_DEBUG
1443 		CTR1(KTR_GEM, "%s: releasing a descriptor", __func__);
1444 #endif
1445 		STAILQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
1446 
1447 		sc->sc_txfree += txs->txs_ndescs;
1448 
1449 		bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
1450 		    BUS_DMASYNC_POSTWRITE);
1451 		bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
1452 		if (txs->txs_mbuf != NULL) {
1453 			m_freem(txs->txs_mbuf);
1454 			txs->txs_mbuf = NULL;
1455 		}
1456 
1457 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
1458 
1459 		ifp->if_opackets++;
1460 		progress = 1;
1461 	}
1462 
1463 #ifdef GEM_DEBUG
1464 	CTR4(KTR_GEM, "%s: GEM_TX_STATE_MACHINE %x GEM_TX_DATA_PTR %llx "
1465 	    "GEM_TX_COMPLETION %x",
1466 	    __func__, GEM_BANK1_READ_4(sc, GEM_TX_STATE_MACHINE),
1467 	    ((long long)GEM_BANK1_READ_4(sc, GEM_TX_DATA_PTR_HI) << 32) |
1468 	    GEM_BANK1_READ_4(sc, GEM_TX_DATA_PTR_LO),
1469 	    GEM_BANK1_READ_4(sc, GEM_TX_COMPLETION));
1470 #endif
1471 
1472 	if (progress) {
1473 		if (sc->sc_txfree == GEM_NTXDESC - 1)
1474 			sc->sc_txwin = 0;
1475 
1476 		/*
1477 		 * We freed some descriptors, so reset IFF_DRV_OACTIVE
1478 		 * and restart.
1479 		 */
1480 		ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
1481 		if (STAILQ_EMPTY(&sc->sc_txdirtyq))
1482 		    sc->sc_wdog_timer = 0;
1483 		gem_start_locked(ifp);
1484 	}
1485 
1486 #ifdef GEM_DEBUG
1487 	CTR3(KTR_GEM, "%s: %s: watchdog %d",
1488 	    device_get_name(sc->sc_dev), __func__, sc->sc_wdog_timer);
1489 #endif
1490 }
1491 
1492 #ifdef GEM_RINT_TIMEOUT
1493 static void
1494 gem_rint_timeout(void *arg)
1495 {
1496 	struct gem_softc *sc = arg;
1497 
1498 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1499 
1500 	gem_rint(sc);
1501 }
1502 #endif
1503 
1504 static void
1505 gem_rint(struct gem_softc *sc)
1506 {
1507 	struct ifnet *ifp = sc->sc_ifp;
1508 	struct mbuf *m;
1509 	uint64_t rxstat;
1510 	uint32_t rxcomp;
1511 
1512 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1513 
1514 #ifdef GEM_RINT_TIMEOUT
1515 	callout_stop(&sc->sc_rx_ch);
1516 #endif
1517 #ifdef GEM_DEBUG
1518 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
1519 #endif
1520 
1521 	/*
1522 	 * Read the completion register once.  This limits
1523 	 * how long the following loop can execute.
1524 	 */
1525 	rxcomp = GEM_BANK1_READ_4(sc, GEM_RX_COMPLETION);
1526 #ifdef GEM_DEBUG
1527 	CTR3(KTR_GEM, "%s: sc->sc_rxptr %d, complete %d",
1528 	    __func__, sc->sc_rxptr, rxcomp);
1529 #endif
1530 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
1531 	for (; sc->sc_rxptr != rxcomp;) {
1532 		m = sc->sc_rxsoft[sc->sc_rxptr].rxs_mbuf;
1533 		rxstat = GEM_DMA_READ(sc,
1534 		    sc->sc_rxdescs[sc->sc_rxptr].gd_flags);
1535 
1536 		if (rxstat & GEM_RD_OWN) {
1537 #ifdef GEM_RINT_TIMEOUT
1538 			/*
1539 			 * The descriptor is still marked as owned, although
1540 			 * it is supposed to have completed.  This has been
1541 			 * observed on some machines.  Just exiting here
1542 			 * might leave the packet sitting around until another
1543 			 * one arrives to trigger a new interrupt, which is
1544 			 * generally undesirable, so set up a timeout.
1545 			 */
1546 			callout_reset(&sc->sc_rx_ch, GEM_RXOWN_TICKS,
1547 			    gem_rint_timeout, sc);
1548 #endif
1549 			m = NULL;
1550 			goto kickit;
1551 		}
1552 
1553 		if (rxstat & GEM_RD_BAD_CRC) {
1554 			ifp->if_ierrors++;
1555 			device_printf(sc->sc_dev, "receive error: CRC error\n");
1556 			GEM_INIT_RXDESC(sc, sc->sc_rxptr);
1557 			m = NULL;
1558 			goto kickit;
1559 		}
1560 
1561 #ifdef GEM_DEBUG
1562 		if ((ifp->if_flags & IFF_DEBUG) != 0) {
1563 			printf("    rxsoft %p descriptor %d: ",
1564 			    &sc->sc_rxsoft[sc->sc_rxptr], sc->sc_rxptr);
1565 			printf("gd_flags: 0x%016llx\t",
1566 			    (long long)GEM_DMA_READ(sc,
1567 			    sc->sc_rxdescs[sc->sc_rxptr].gd_flags));
1568 			printf("gd_addr: 0x%016llx\n",
1569 			    (long long)GEM_DMA_READ(sc,
1570 			    sc->sc_rxdescs[sc->sc_rxptr].gd_addr));
1571 		}
1572 #endif
1573 
1574 		/*
1575 		 * Allocate a new mbuf cluster.  If that fails, we are
1576 		 * out of memory, and must drop the packet and recycle
1577 		 * the buffer that's already attached to this descriptor.
1578 		 */
1579 		if (gem_add_rxbuf(sc, sc->sc_rxptr) != 0) {
1580 			ifp->if_ierrors++;
1581 			GEM_INIT_RXDESC(sc, sc->sc_rxptr);
1582 			m = NULL;
1583 		}
1584 
1585  kickit:
1586 		/*
1587 		 * Update the RX kick register.  This register has to point
1588 		 * to the descriptor after the last valid one (before the
1589 		 * current batch) and for optimum performance should be
1590 		 * incremented in multiples of 4 (the DMA engine fetches/
1591 		 * updates descriptors in batches of 4).
1592 		 */
1593 		sc->sc_rxptr = GEM_NEXTRX(sc->sc_rxptr);
1594 		if ((sc->sc_rxptr % 4) == 0) {
1595 			GEM_CDSYNC(sc,
1596 			    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1597 			GEM_BANK1_WRITE_4(sc, GEM_RX_KICK,
1598 			    (sc->sc_rxptr + GEM_NRXDESC - 4) &
1599 			    GEM_NRXDESC_MASK);
1600 		}
1601 
1602 		if (m == NULL) {
1603 			if (rxstat & GEM_RD_OWN)
1604 				break;
1605 			continue;
1606 		}
1607 
1608 		ifp->if_ipackets++;
1609 		m->m_data += ETHER_ALIGN; /* first byte offset */
1610 		m->m_pkthdr.rcvif = ifp;
1611 		m->m_pkthdr.len = m->m_len = GEM_RD_BUFLEN(rxstat);
1612 
1613 		if ((ifp->if_capenable & IFCAP_RXCSUM) != 0)
1614 			gem_rxcksum(m, rxstat);
1615 
1616 		/* Pass it on. */
1617 		GEM_UNLOCK(sc);
1618 		(*ifp->if_input)(ifp, m);
1619 		GEM_LOCK(sc);
1620 	}
1621 
1622 #ifdef GEM_DEBUG
1623 	CTR3(KTR_GEM, "%s: done sc->sc_rxptr %d, complete %d", __func__,
1624 	    sc->sc_rxptr, GEM_BANK1_READ_4(sc, GEM_RX_COMPLETION));
1625 #endif
1626 }
1627 
1628 static int
1629 gem_add_rxbuf(struct gem_softc *sc, int idx)
1630 {
1631 	struct gem_rxsoft *rxs = &sc->sc_rxsoft[idx];
1632 	struct mbuf *m;
1633 	bus_dma_segment_t segs[1];
1634 	int error, nsegs;
1635 
1636 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1637 
1638 	m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
1639 	if (m == NULL)
1640 		return (ENOBUFS);
1641 	m->m_len = m->m_pkthdr.len = m->m_ext.ext_size;
1642 
1643 #ifdef GEM_DEBUG
1644 	/* Bzero the packet to check DMA. */
1645 	memset(m->m_ext.ext_buf, 0, m->m_ext.ext_size);
1646 #endif
1647 
1648 	if (rxs->rxs_mbuf != NULL) {
1649 		bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
1650 		    BUS_DMASYNC_POSTREAD);
1651 		bus_dmamap_unload(sc->sc_rdmatag, rxs->rxs_dmamap);
1652 	}
1653 
1654 	error = bus_dmamap_load_mbuf_sg(sc->sc_rdmatag, rxs->rxs_dmamap,
1655 	    m, segs, &nsegs, BUS_DMA_NOWAIT);
1656 	if (error != 0) {
1657 		device_printf(sc->sc_dev,
1658 		    "cannot load RS DMA map %d, error = %d\n", idx, error);
1659 		m_freem(m);
1660 		return (error);
1661 	}
1662 	/* If nsegs is wrong then the stack is corrupt. */
1663 	KASSERT(nsegs == 1,
1664 	    ("%s: too many DMA segments (%d)", __func__, nsegs));
1665 	rxs->rxs_mbuf = m;
1666 	rxs->rxs_paddr = segs[0].ds_addr;
1667 
1668 	bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
1669 	    BUS_DMASYNC_PREREAD);
1670 
1671 	GEM_INIT_RXDESC(sc, idx);
1672 
1673 	return (0);
1674 }
1675 
1676 static void
1677 gem_eint(struct gem_softc *sc, u_int status)
1678 {
1679 
1680 	sc->sc_ifp->if_ierrors++;
1681 	if ((status & GEM_INTR_RX_TAG_ERR) != 0) {
1682 		gem_reset_rxdma(sc);
1683 		return;
1684 	}
1685 
1686 	device_printf(sc->sc_dev, "%s: status 0x%x", __func__, status);
1687 	if ((status & GEM_INTR_BERR) != 0) {
1688 		if ((sc->sc_flags & GEM_PCI) != 0)
1689 			printf(", PCI bus error 0x%x\n",
1690 			    GEM_BANK1_READ_4(sc, GEM_PCI_ERROR_STATUS));
1691 		else
1692 			printf(", SBus error 0x%x\n",
1693 			    GEM_BANK1_READ_4(sc, GEM_SBUS_STATUS));
1694 	}
1695 }
1696 
1697 void
1698 gem_intr(void *v)
1699 {
1700 	struct gem_softc *sc = v;
1701 	uint32_t status, status2;
1702 
1703 	GEM_LOCK(sc);
1704 	status = GEM_BANK1_READ_4(sc, GEM_STATUS);
1705 
1706 #ifdef GEM_DEBUG
1707 	CTR4(KTR_GEM, "%s: %s: cplt %x, status %x",
1708 	    device_get_name(sc->sc_dev), __func__,
1709 	    (status >> GEM_STATUS_TX_COMPLETION_SHFT), (u_int)status);
1710 
1711 	/*
1712 	 * PCS interrupts must be cleared, otherwise no traffic is passed!
1713 	 */
1714 	if ((status & GEM_INTR_PCS) != 0) {
1715 		status2 =
1716 		    GEM_BANK1_READ_4(sc, GEM_MII_INTERRUP_STATUS) |
1717 		    GEM_BANK1_READ_4(sc, GEM_MII_INTERRUP_STATUS);
1718 		if ((status2 & GEM_MII_INTERRUP_LINK) != 0)
1719 			device_printf(sc->sc_dev,
1720 			    "%s: PCS link status changed\n", __func__);
1721 	}
1722 	if ((status & GEM_MAC_CONTROL_STATUS) != 0) {
1723 		status2 = GEM_BANK1_READ_4(sc, GEM_MAC_CONTROL_STATUS);
1724 		if ((status2 & GEM_MAC_PAUSED) != 0)
1725 			device_printf(sc->sc_dev,
1726 			    "%s: PAUSE received (PAUSE time %d slots)\n",
1727 			    __func__, GEM_MAC_PAUSE_TIME(status2));
1728 		if ((status2 & GEM_MAC_PAUSE) != 0)
1729 			device_printf(sc->sc_dev,
1730 			    "%s: transited to PAUSE state\n", __func__);
1731 		if ((status2 & GEM_MAC_RESUME) != 0)
1732 			device_printf(sc->sc_dev,
1733 			    "%s: transited to non-PAUSE state\n", __func__);
1734 	}
1735 	if ((status & GEM_INTR_MIF) != 0)
1736 		device_printf(sc->sc_dev, "%s: MIF interrupt\n", __func__);
1737 #endif
1738 
1739 	if (__predict_false(status &
1740 	    (GEM_INTR_RX_TAG_ERR | GEM_INTR_PERR | GEM_INTR_BERR)) != 0)
1741 		gem_eint(sc, status);
1742 
1743 	if ((status & (GEM_INTR_RX_DONE | GEM_INTR_RX_NOBUF)) != 0)
1744 		gem_rint(sc);
1745 
1746 	if ((status & (GEM_INTR_TX_EMPTY | GEM_INTR_TX_INTME)) != 0)
1747 		gem_tint(sc);
1748 
1749 	if (__predict_false((status & GEM_INTR_TX_MAC) != 0)) {
1750 		status2 = GEM_BANK1_READ_4(sc, GEM_MAC_TX_STATUS);
1751 		if ((status2 &
1752 		    ~(GEM_MAC_TX_XMIT_DONE | GEM_MAC_TX_DEFER_EXP |
1753 		    GEM_MAC_TX_PEAK_EXP)) != 0)
1754 			device_printf(sc->sc_dev,
1755 			    "MAC TX fault, status %x\n", status2);
1756 		if ((status2 &
1757 		    (GEM_MAC_TX_UNDERRUN | GEM_MAC_TX_PKT_TOO_LONG)) != 0) {
1758 			sc->sc_ifp->if_oerrors++;
1759 			gem_init_locked(sc);
1760 		}
1761 	}
1762 	if (__predict_false((status & GEM_INTR_RX_MAC) != 0)) {
1763 		status2 = GEM_BANK1_READ_4(sc, GEM_MAC_RX_STATUS);
1764 		/*
1765 		 * At least with GEM_SUN_GEM and some GEM_SUN_ERI
1766 		 * revisions GEM_MAC_RX_OVERFLOW happen often due to a
1767 		 * silicon bug so handle them silently.  Moreover, it's
1768 		 * likely that the receiver has hung so we reset it.
1769 		 */
1770 		if ((status2 & GEM_MAC_RX_OVERFLOW) != 0) {
1771 			sc->sc_ifp->if_ierrors++;
1772 			gem_reset_rxdma(sc);
1773 		} else if ((status2 &
1774 		    ~(GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT)) != 0)
1775 			device_printf(sc->sc_dev,
1776 			    "MAC RX fault, status %x\n", status2);
1777 	}
1778 	GEM_UNLOCK(sc);
1779 }
1780 
1781 static int
1782 gem_watchdog(struct gem_softc *sc)
1783 {
1784 	struct ifnet *ifp = sc->sc_ifp;
1785 
1786 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1787 
1788 #ifdef GEM_DEBUG
1789 	CTR4(KTR_GEM,
1790 	    "%s: GEM_RX_CONFIG %x GEM_MAC_RX_STATUS %x GEM_MAC_RX_CONFIG %x",
1791 	    __func__, GEM_BANK1_READ_4(sc, GEM_RX_CONFIG),
1792 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_STATUS),
1793 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG));
1794 	CTR4(KTR_GEM,
1795 	    "%s: GEM_TX_CONFIG %x GEM_MAC_TX_STATUS %x GEM_MAC_TX_CONFIG %x",
1796 	    __func__, GEM_BANK1_READ_4(sc, GEM_TX_CONFIG),
1797 	    GEM_BANK1_READ_4(sc, GEM_MAC_TX_STATUS),
1798 	    GEM_BANK1_READ_4(sc, GEM_MAC_TX_CONFIG));
1799 #endif
1800 
1801 	if (sc->sc_wdog_timer == 0 || --sc->sc_wdog_timer != 0)
1802 		return (0);
1803 
1804 	if ((sc->sc_flags & GEM_LINK) != 0)
1805 		device_printf(sc->sc_dev, "device timeout\n");
1806 	else if (bootverbose)
1807 		device_printf(sc->sc_dev, "device timeout (no link)\n");
1808 	++ifp->if_oerrors;
1809 
1810 	/* Try to get more packets going. */
1811 	gem_init_locked(sc);
1812 	gem_start_locked(ifp);
1813 	return (EJUSTRETURN);
1814 }
1815 
1816 static void
1817 gem_mifinit(struct gem_softc *sc)
1818 {
1819 
1820 	/* Configure the MIF in frame mode. */
1821 	GEM_BANK1_WRITE_4(sc, GEM_MIF_CONFIG,
1822 	    GEM_BANK1_READ_4(sc, GEM_MIF_CONFIG) & ~GEM_MIF_CONFIG_BB_ENA);
1823 	GEM_BANK1_BARRIER(sc, GEM_MIF_CONFIG, 4,
1824 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1825 }
1826 
1827 /*
1828  * MII interface
1829  *
1830  * The MII interface supports at least three different operating modes:
1831  *
1832  * Bitbang mode is implemented using data, clock and output enable registers.
1833  *
1834  * Frame mode is implemented by loading a complete frame into the frame
1835  * register and polling the valid bit for completion.
1836  *
1837  * Polling mode uses the frame register but completion is indicated by
1838  * an interrupt.
1839  *
1840  */
1841 int
1842 gem_mii_readreg(device_t dev, int phy, int reg)
1843 {
1844 	struct gem_softc *sc;
1845 	int n;
1846 	uint32_t v;
1847 
1848 #ifdef GEM_DEBUG_PHY
1849 	printf("%s: phy %d reg %d\n", __func__, phy, reg);
1850 #endif
1851 
1852 	sc = device_get_softc(dev);
1853 	if ((sc->sc_flags & GEM_SERDES) != 0) {
1854 		switch (reg) {
1855 		case MII_BMCR:
1856 			reg = GEM_MII_CONTROL;
1857 			break;
1858 		case MII_BMSR:
1859 			reg = GEM_MII_STATUS;
1860 			break;
1861 		case MII_PHYIDR1:
1862 		case MII_PHYIDR2:
1863 			return (0);
1864 		case MII_ANAR:
1865 			reg = GEM_MII_ANAR;
1866 			break;
1867 		case MII_ANLPAR:
1868 			reg = GEM_MII_ANLPAR;
1869 			break;
1870 		case MII_EXTSR:
1871 			return (EXTSR_1000XFDX | EXTSR_1000XHDX);
1872 		default:
1873 			device_printf(sc->sc_dev,
1874 			    "%s: unhandled register %d\n", __func__, reg);
1875 			return (0);
1876 		}
1877 		return (GEM_BANK1_READ_4(sc, reg));
1878 	}
1879 
1880 	/* Construct the frame command. */
1881 	v = GEM_MIF_FRAME_READ |
1882 	    (phy << GEM_MIF_PHY_SHIFT) |
1883 	    (reg << GEM_MIF_REG_SHIFT);
1884 
1885 	GEM_BANK1_WRITE_4(sc, GEM_MIF_FRAME, v);
1886 	GEM_BANK1_BARRIER(sc, GEM_MIF_FRAME, 4,
1887 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1888 	for (n = 0; n < 100; n++) {
1889 		DELAY(1);
1890 		v = GEM_BANK1_READ_4(sc, GEM_MIF_FRAME);
1891 		if (v & GEM_MIF_FRAME_TA0)
1892 			return (v & GEM_MIF_FRAME_DATA);
1893 	}
1894 
1895 	device_printf(sc->sc_dev, "%s: timed out\n", __func__);
1896 	return (0);
1897 }
1898 
1899 int
1900 gem_mii_writereg(device_t dev, int phy, int reg, int val)
1901 {
1902 	struct gem_softc *sc;
1903 	int n;
1904 	uint32_t v;
1905 
1906 #ifdef GEM_DEBUG_PHY
1907 	printf("%s: phy %d reg %d val %x\n", phy, reg, val, __func__);
1908 #endif
1909 
1910 	sc = device_get_softc(dev);
1911 	if ((sc->sc_flags & GEM_SERDES) != 0) {
1912 		switch (reg) {
1913 		case MII_BMSR:
1914 			reg = GEM_MII_STATUS;
1915 			break;
1916 		case MII_BMCR:
1917 			reg = GEM_MII_CONTROL;
1918 			if ((val & GEM_MII_CONTROL_RESET) == 0)
1919 				break;
1920 			GEM_BANK1_WRITE_4(sc, GEM_MII_CONTROL, val);
1921 			GEM_BANK1_BARRIER(sc, GEM_MII_CONTROL, 4,
1922 			    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1923 			if (!GEM_BANK1_BITWAIT(sc, GEM_MII_CONTROL,
1924 			    GEM_MII_CONTROL_RESET, 0))
1925 				device_printf(sc->sc_dev,
1926 				    "cannot reset PCS\n");
1927 			/* FALLTHROUGH */
1928 		case MII_ANAR:
1929 			GEM_BANK1_WRITE_4(sc, GEM_MII_CONFIG, 0);
1930 			GEM_BANK1_BARRIER(sc, GEM_MII_CONFIG, 4,
1931 			    BUS_SPACE_BARRIER_WRITE);
1932 			GEM_BANK1_WRITE_4(sc, GEM_MII_ANAR, val);
1933 			GEM_BANK1_BARRIER(sc, GEM_MII_ANAR, 4,
1934 			    BUS_SPACE_BARRIER_WRITE);
1935 			GEM_BANK1_WRITE_4(sc, GEM_MII_SLINK_CONTROL,
1936 			    GEM_MII_SLINK_LOOPBACK | GEM_MII_SLINK_EN_SYNC_D);
1937 			GEM_BANK1_BARRIER(sc, GEM_MII_SLINK_CONTROL, 4,
1938 			    BUS_SPACE_BARRIER_WRITE);
1939 			GEM_BANK1_WRITE_4(sc, GEM_MII_CONFIG,
1940 			    GEM_MII_CONFIG_ENABLE);
1941 			GEM_BANK1_BARRIER(sc, GEM_MII_CONFIG, 4,
1942 			    BUS_SPACE_BARRIER_WRITE);
1943 			return (0);
1944 		case MII_ANLPAR:
1945 			reg = GEM_MII_ANLPAR;
1946 			break;
1947 		default:
1948 			device_printf(sc->sc_dev,
1949 			    "%s: unhandled register %d\n", __func__, reg);
1950 			return (0);
1951 		}
1952 		GEM_BANK1_WRITE_4(sc, reg, val);
1953 		GEM_BANK1_BARRIER(sc, reg, 4,
1954 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1955 		return (0);
1956 	}
1957 
1958 	/* Construct the frame command. */
1959 	v = GEM_MIF_FRAME_WRITE |
1960 	    (phy << GEM_MIF_PHY_SHIFT) |
1961 	    (reg << GEM_MIF_REG_SHIFT) |
1962 	    (val & GEM_MIF_FRAME_DATA);
1963 
1964 	GEM_BANK1_WRITE_4(sc, GEM_MIF_FRAME, v);
1965 	GEM_BANK1_BARRIER(sc, GEM_MIF_FRAME, 4,
1966 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1967 	for (n = 0; n < 100; n++) {
1968 		DELAY(1);
1969 		v = GEM_BANK1_READ_4(sc, GEM_MIF_FRAME);
1970 		if (v & GEM_MIF_FRAME_TA0)
1971 			return (1);
1972 	}
1973 
1974 	device_printf(sc->sc_dev, "%s: timed out\n", __func__);
1975 	return (0);
1976 }
1977 
1978 void
1979 gem_mii_statchg(device_t dev)
1980 {
1981 	struct gem_softc *sc;
1982 	int gigabit;
1983 	uint32_t rxcfg, txcfg, v;
1984 
1985 	sc = device_get_softc(dev);
1986 
1987 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1988 
1989 #ifdef GEM_DEBUG
1990 	if ((sc->sc_ifp->if_flags & IFF_DEBUG) != 0)
1991 		device_printf(sc->sc_dev, "%s: status change\n", __func__);
1992 #endif
1993 
1994 	if ((sc->sc_mii->mii_media_status & IFM_ACTIVE) != 0 &&
1995 	    IFM_SUBTYPE(sc->sc_mii->mii_media_active) != IFM_NONE)
1996 		sc->sc_flags |= GEM_LINK;
1997 	else
1998 		sc->sc_flags &= ~GEM_LINK;
1999 
2000 	switch (IFM_SUBTYPE(sc->sc_mii->mii_media_active)) {
2001 	case IFM_1000_SX:
2002 	case IFM_1000_LX:
2003 	case IFM_1000_CX:
2004 	case IFM_1000_T:
2005 		gigabit = 1;
2006 		break;
2007 	default:
2008 		gigabit = 0;
2009 	}
2010 
2011 	/*
2012 	 * The configuration done here corresponds to the steps F) and
2013 	 * G) and as far as enabling of RX and TX MAC goes also step H)
2014 	 * of the initialization sequence outlined in section 3.2.1 of
2015 	 * the GEM Gigabit Ethernet ASIC Specification.
2016 	 */
2017 
2018 	rxcfg = GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG);
2019 	rxcfg &= ~(GEM_MAC_RX_CARR_EXTEND | GEM_MAC_RX_ENABLE);
2020 	txcfg = GEM_MAC_TX_ENA_IPG0 | GEM_MAC_TX_NGU | GEM_MAC_TX_NGU_LIMIT;
2021 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) != 0)
2022 		txcfg |= GEM_MAC_TX_IGN_CARRIER | GEM_MAC_TX_IGN_COLLIS;
2023 	else if (gigabit != 0) {
2024 		rxcfg |= GEM_MAC_RX_CARR_EXTEND;
2025 		txcfg |= GEM_MAC_TX_CARR_EXTEND;
2026 	}
2027 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG, 0);
2028 	GEM_BANK1_BARRIER(sc, GEM_MAC_TX_CONFIG, 4,
2029 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
2030 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_TX_CONFIG, GEM_MAC_TX_ENABLE, 0))
2031 		device_printf(sc->sc_dev, "cannot disable TX MAC\n");
2032 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG, txcfg);
2033 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, 0);
2034 	GEM_BANK1_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
2035 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
2036 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_ENABLE, 0))
2037 		device_printf(sc->sc_dev, "cannot disable RX MAC\n");
2038 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, rxcfg);
2039 
2040 	v = GEM_BANK1_READ_4(sc, GEM_MAC_CONTROL_CONFIG) &
2041 	    ~(GEM_MAC_CC_RX_PAUSE | GEM_MAC_CC_TX_PAUSE);
2042 #ifdef notyet
2043 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
2044 	    IFM_ETH_RXPAUSE) != 0)
2045 		v |= GEM_MAC_CC_RX_PAUSE;
2046 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
2047 	    IFM_ETH_TXPAUSE) != 0)
2048 		v |= GEM_MAC_CC_TX_PAUSE;
2049 #endif
2050 	GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_CONFIG, v);
2051 
2052 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) == 0 &&
2053 	    gigabit != 0)
2054 		GEM_BANK1_WRITE_4(sc, GEM_MAC_SLOT_TIME,
2055 		    GEM_MAC_SLOT_TIME_CARR_EXTEND);
2056 	else
2057 		GEM_BANK1_WRITE_4(sc, GEM_MAC_SLOT_TIME,
2058 		    GEM_MAC_SLOT_TIME_NORMAL);
2059 
2060 	/* XIF Configuration */
2061 	v = GEM_MAC_XIF_LINK_LED;
2062 	v |= GEM_MAC_XIF_TX_MII_ENA;
2063 	if ((sc->sc_flags & GEM_SERDES) == 0) {
2064 		if ((GEM_BANK1_READ_4(sc, GEM_MIF_CONFIG) &
2065 		    GEM_MIF_CONFIG_PHY_SEL) != 0) {
2066 			/* External MII needs echo disable if half duplex. */
2067 			if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
2068 			    IFM_FDX) == 0)
2069 				v |= GEM_MAC_XIF_ECHO_DISABL;
2070 		} else
2071 			/*
2072 			 * Internal MII needs buffer enable.
2073 			 * XXX buffer enable makes only sense for an
2074 			 * external PHY.
2075 			 */
2076 			v |= GEM_MAC_XIF_MII_BUF_ENA;
2077 	}
2078 	if (gigabit != 0)
2079 		v |= GEM_MAC_XIF_GMII_MODE;
2080 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) != 0)
2081 		v |= GEM_MAC_XIF_FDPLX_LED;
2082 	GEM_BANK1_WRITE_4(sc, GEM_MAC_XIF_CONFIG, v);
2083 
2084 	if ((sc->sc_ifp->if_drv_flags & IFF_DRV_RUNNING) != 0 &&
2085 	    (sc->sc_flags & GEM_LINK) != 0) {
2086 		GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG,
2087 		    txcfg | GEM_MAC_TX_ENABLE);
2088 		GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG,
2089 		    rxcfg | GEM_MAC_RX_ENABLE);
2090 	}
2091 }
2092 
2093 int
2094 gem_mediachange(struct ifnet *ifp)
2095 {
2096 	struct gem_softc *sc = ifp->if_softc;
2097 	int error;
2098 
2099 	/* XXX add support for serial media. */
2100 
2101 	GEM_LOCK(sc);
2102 	error = mii_mediachg(sc->sc_mii);
2103 	GEM_UNLOCK(sc);
2104 	return (error);
2105 }
2106 
2107 void
2108 gem_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
2109 {
2110 	struct gem_softc *sc = ifp->if_softc;
2111 
2112 	GEM_LOCK(sc);
2113 	if ((ifp->if_flags & IFF_UP) == 0) {
2114 		GEM_UNLOCK(sc);
2115 		return;
2116 	}
2117 
2118 	mii_pollstat(sc->sc_mii);
2119 	ifmr->ifm_active = sc->sc_mii->mii_media_active;
2120 	ifmr->ifm_status = sc->sc_mii->mii_media_status;
2121 	GEM_UNLOCK(sc);
2122 }
2123 
2124 static int
2125 gem_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
2126 {
2127 	struct gem_softc *sc = ifp->if_softc;
2128 	struct ifreq *ifr = (struct ifreq *)data;
2129 	int error;
2130 
2131 	error = 0;
2132 	switch (cmd) {
2133 	case SIOCSIFFLAGS:
2134 		GEM_LOCK(sc);
2135 		if ((ifp->if_flags & IFF_UP) != 0) {
2136 			if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0 &&
2137 			    ((ifp->if_flags ^ sc->sc_ifflags) &
2138 			    (IFF_ALLMULTI | IFF_PROMISC)) != 0)
2139 				gem_setladrf(sc);
2140 			else
2141 				gem_init_locked(sc);
2142 		} else if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
2143 			gem_stop(ifp, 0);
2144 		if ((ifp->if_flags & IFF_LINK0) != 0)
2145 			sc->sc_csum_features |= CSUM_UDP;
2146 		else
2147 			sc->sc_csum_features &= ~CSUM_UDP;
2148 		if ((ifp->if_capenable & IFCAP_TXCSUM) != 0)
2149 			ifp->if_hwassist = sc->sc_csum_features;
2150 		sc->sc_ifflags = ifp->if_flags;
2151 		GEM_UNLOCK(sc);
2152 		break;
2153 	case SIOCADDMULTI:
2154 	case SIOCDELMULTI:
2155 		GEM_LOCK(sc);
2156 		gem_setladrf(sc);
2157 		GEM_UNLOCK(sc);
2158 		break;
2159 	case SIOCGIFMEDIA:
2160 	case SIOCSIFMEDIA:
2161 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii->mii_media, cmd);
2162 		break;
2163 	case SIOCSIFCAP:
2164 		GEM_LOCK(sc);
2165 		ifp->if_capenable = ifr->ifr_reqcap;
2166 		if ((ifp->if_capenable & IFCAP_TXCSUM) != 0)
2167 			ifp->if_hwassist = sc->sc_csum_features;
2168 		else
2169 			ifp->if_hwassist = 0;
2170 		GEM_UNLOCK(sc);
2171 		break;
2172 	default:
2173 		error = ether_ioctl(ifp, cmd, data);
2174 		break;
2175 	}
2176 
2177 	return (error);
2178 }
2179 
2180 static void
2181 gem_setladrf(struct gem_softc *sc)
2182 {
2183 	struct ifnet *ifp = sc->sc_ifp;
2184 	struct ifmultiaddr *inm;
2185 	int i;
2186 	uint32_t hash[16];
2187 	uint32_t crc, v;
2188 
2189 	GEM_LOCK_ASSERT(sc, MA_OWNED);
2190 
2191 	/* Get the current RX configuration. */
2192 	v = GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG);
2193 
2194 	/*
2195 	 * Turn off promiscuous mode, promiscuous group mode (all multicast),
2196 	 * and hash filter.  Depending on the case, the right bit will be
2197 	 * enabled.
2198 	 */
2199 	v &= ~(GEM_MAC_RX_PROMISCUOUS | GEM_MAC_RX_HASH_FILTER |
2200 	    GEM_MAC_RX_PROMISC_GRP);
2201 
2202 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, v);
2203 	GEM_BANK1_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
2204 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
2205 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_HASH_FILTER,
2206 	    0))
2207 		device_printf(sc->sc_dev, "cannot disable RX hash filter\n");
2208 
2209 	if ((ifp->if_flags & IFF_PROMISC) != 0) {
2210 		v |= GEM_MAC_RX_PROMISCUOUS;
2211 		goto chipit;
2212 	}
2213 	if ((ifp->if_flags & IFF_ALLMULTI) != 0) {
2214 		v |= GEM_MAC_RX_PROMISC_GRP;
2215 		goto chipit;
2216 	}
2217 
2218 	/*
2219 	 * Set up multicast address filter by passing all multicast
2220 	 * addresses through a crc generator, and then using the high
2221 	 * order 8 bits as an index into the 256 bit logical address
2222 	 * filter.  The high order 4 bits selects the word, while the
2223 	 * other 4 bits select the bit within the word (where bit 0
2224 	 * is the MSB).
2225 	 */
2226 
2227 	/* Clear the hash table. */
2228 	memset(hash, 0, sizeof(hash));
2229 
2230 	if_maddr_rlock(ifp);
2231 	TAILQ_FOREACH(inm, &ifp->if_multiaddrs, ifma_link) {
2232 		if (inm->ifma_addr->sa_family != AF_LINK)
2233 			continue;
2234 		crc = ether_crc32_le(LLADDR((struct sockaddr_dl *)
2235 		    inm->ifma_addr), ETHER_ADDR_LEN);
2236 
2237 		/* We just want the 8 most significant bits. */
2238 		crc >>= 24;
2239 
2240 		/* Set the corresponding bit in the filter. */
2241 		hash[crc >> 4] |= 1 << (15 - (crc & 15));
2242 	}
2243 	if_maddr_runlock(ifp);
2244 
2245 	v |= GEM_MAC_RX_HASH_FILTER;
2246 
2247 	/* Now load the hash table into the chip (if we are using it). */
2248 	for (i = 0; i < 16; i++)
2249 		GEM_BANK1_WRITE_4(sc,
2250 		    GEM_MAC_HASH0 + i * (GEM_MAC_HASH1 - GEM_MAC_HASH0),
2251 		    hash[i]);
2252 
2253  chipit:
2254 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, v);
2255 }
2256