xref: /freebsd/sys/dev/gem/if_gem.c (revision 8fc257994d0ce2396196d7a06d50d20c8015f4b7)
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_CT2
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;
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 	/* Bad things will happen when touching this register on ERI. */
272 	if (sc->sc_variant != GEM_SUN_ERI)
273 		GEM_BANK1_WRITE_4(sc, GEM_MII_DATAPATH_MODE,
274 		    GEM_MII_DATAPATH_MII);
275 
276 	gem_mifinit(sc);
277 
278 	/*
279 	 * Look for an external PHY.
280 	 */
281 	error = ENXIO;
282 	v = GEM_BANK1_READ_4(sc, GEM_MIF_CONFIG);
283 	if ((v & GEM_MIF_CONFIG_MDI1) != 0) {
284 		v |= GEM_MIF_CONFIG_PHY_SEL;
285 		GEM_BANK1_WRITE_4(sc, GEM_MIF_CONFIG, v);
286 		switch (sc->sc_variant) {
287 		case GEM_SUN_ERI:
288 			sc->sc_phyad = GEM_PHYAD_EXTERNAL;
289 			break;
290 		default:
291 			sc->sc_phyad = -1;
292 			break;
293 		}
294 		error = mii_phy_probe(sc->sc_dev, &sc->sc_miibus,
295 		    gem_mediachange, gem_mediastatus);
296 	}
297 
298 	/*
299 	 * Fall back on an internal PHY if no external PHY was found.
300 	 * Note that with Apple (K2) GMACs GEM_MIF_CONFIG_MDI0 can't be
301 	 * trusted when the firmware has powered down the chip.
302 	 */
303 	if (error != 0 &&
304 	    ((v & GEM_MIF_CONFIG_MDI0) != 0 || GEM_IS_APPLE(sc))) {
305 		v &= ~GEM_MIF_CONFIG_PHY_SEL;
306 		GEM_BANK1_WRITE_4(sc, GEM_MIF_CONFIG, v);
307 		switch (sc->sc_variant) {
308 		case GEM_SUN_ERI:
309 		case GEM_APPLE_K2_GMAC:
310 			sc->sc_phyad = GEM_PHYAD_INTERNAL;
311 			break;
312 		case GEM_APPLE_GMAC:
313 			sc->sc_phyad = GEM_PHYAD_EXTERNAL;
314 			break;
315 		default:
316 			sc->sc_phyad = -1;
317 			break;
318 		}
319 		error = mii_phy_probe(sc->sc_dev, &sc->sc_miibus,
320 		    gem_mediachange, gem_mediastatus);
321 	}
322 
323 	/*
324 	 * Try the external PCS SERDES if we didn't find any PHYs.
325 	 */
326 	if (error != 0 && sc->sc_variant == GEM_SUN_GEM) {
327 		GEM_BANK1_WRITE_4(sc, GEM_MII_DATAPATH_MODE,
328 		    GEM_MII_DATAPATH_SERDES);
329 		GEM_BANK1_WRITE_4(sc, GEM_MII_SLINK_CONTROL,
330 		    GEM_MII_SLINK_LOOPBACK | GEM_MII_SLINK_EN_SYNC_D);
331 		GEM_BANK1_WRITE_4(sc, GEM_MII_CONFIG, GEM_MII_CONFIG_ENABLE);
332 		sc->sc_flags |= GEM_SERDES;
333 		sc->sc_phyad = GEM_PHYAD_EXTERNAL;
334 		error = mii_phy_probe(sc->sc_dev, &sc->sc_miibus,
335 		    gem_mediachange, gem_mediastatus);
336 	}
337 
338 	if (error != 0) {
339 		device_printf(sc->sc_dev, "PHY probe failed: %d\n", error);
340 		goto fail_rxd;
341 	}
342 	sc->sc_mii = device_get_softc(sc->sc_miibus);
343 
344 	/*
345 	 * From this point forward, the attachment cannot fail.  A failure
346 	 * before this point releases all resources that may have been
347 	 * allocated.
348 	 */
349 
350 	/* Get RX FIFO size. */
351 	sc->sc_rxfifosize = 64 *
352 	    GEM_BANK1_READ_4(sc, GEM_RX_FIFO_SIZE);
353 
354 	/* Get TX FIFO size. */
355 	v = GEM_BANK1_READ_4(sc, GEM_TX_FIFO_SIZE);
356 	device_printf(sc->sc_dev, "%ukB RX FIFO, %ukB TX FIFO\n",
357 	    sc->sc_rxfifosize / 1024, v / 16);
358 
359 	/* Attach the interface. */
360 	ether_ifattach(ifp, sc->sc_enaddr);
361 
362 	/*
363 	 * Tell the upper layer(s) we support long frames/checksum offloads.
364 	 */
365 	ifp->if_data.ifi_hdrlen = sizeof(struct ether_vlan_header);
366 	ifp->if_capabilities |= IFCAP_VLAN_MTU | IFCAP_HWCSUM;
367 	ifp->if_hwassist |= sc->sc_csum_features;
368 	ifp->if_capenable |= IFCAP_VLAN_MTU | IFCAP_HWCSUM;
369 
370 	return (0);
371 
372 	/*
373 	 * Free any resources we've allocated during the failed attach
374 	 * attempt.  Do this in reverse order and fall through.
375 	 */
376  fail_rxd:
377 	for (i = 0; i < GEM_NRXDESC; i++)
378 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
379 			bus_dmamap_destroy(sc->sc_rdmatag,
380 			    sc->sc_rxsoft[i].rxs_dmamap);
381  fail_txd:
382 	for (i = 0; i < GEM_TXQUEUELEN; i++)
383 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
384 			bus_dmamap_destroy(sc->sc_tdmatag,
385 			    sc->sc_txsoft[i].txs_dmamap);
386 	bus_dmamap_unload(sc->sc_cdmatag, sc->sc_cddmamap);
387  fail_cmem:
388 	bus_dmamem_free(sc->sc_cdmatag, sc->sc_control_data,
389 	    sc->sc_cddmamap);
390  fail_ctag:
391 	bus_dma_tag_destroy(sc->sc_cdmatag);
392  fail_ttag:
393 	bus_dma_tag_destroy(sc->sc_tdmatag);
394  fail_rtag:
395 	bus_dma_tag_destroy(sc->sc_rdmatag);
396  fail_ptag:
397 	bus_dma_tag_destroy(sc->sc_pdmatag);
398  fail_ifnet:
399 	if_free(ifp);
400 	return (error);
401 }
402 
403 void
404 gem_detach(struct gem_softc *sc)
405 {
406 	struct ifnet *ifp = sc->sc_ifp;
407 	int i;
408 
409 	ether_ifdetach(ifp);
410 	GEM_LOCK(sc);
411 	gem_stop(ifp, 1);
412 	GEM_UNLOCK(sc);
413 	callout_drain(&sc->sc_tick_ch);
414 #ifdef GEM_RINT_TIMEOUT
415 	callout_drain(&sc->sc_rx_ch);
416 #endif
417 	if_free(ifp);
418 	device_delete_child(sc->sc_dev, sc->sc_miibus);
419 
420 	for (i = 0; i < GEM_NRXDESC; i++)
421 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
422 			bus_dmamap_destroy(sc->sc_rdmatag,
423 			    sc->sc_rxsoft[i].rxs_dmamap);
424 	for (i = 0; i < GEM_TXQUEUELEN; i++)
425 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
426 			bus_dmamap_destroy(sc->sc_tdmatag,
427 			    sc->sc_txsoft[i].txs_dmamap);
428 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
429 	bus_dmamap_unload(sc->sc_cdmatag, sc->sc_cddmamap);
430 	bus_dmamem_free(sc->sc_cdmatag, sc->sc_control_data,
431 	    sc->sc_cddmamap);
432 	bus_dma_tag_destroy(sc->sc_cdmatag);
433 	bus_dma_tag_destroy(sc->sc_tdmatag);
434 	bus_dma_tag_destroy(sc->sc_rdmatag);
435 	bus_dma_tag_destroy(sc->sc_pdmatag);
436 }
437 
438 void
439 gem_suspend(struct gem_softc *sc)
440 {
441 	struct ifnet *ifp = sc->sc_ifp;
442 
443 	GEM_LOCK(sc);
444 	gem_stop(ifp, 0);
445 	GEM_UNLOCK(sc);
446 }
447 
448 void
449 gem_resume(struct gem_softc *sc)
450 {
451 	struct ifnet *ifp = sc->sc_ifp;
452 
453 	GEM_LOCK(sc);
454 	/*
455 	 * On resume all registers have to be initialized again like
456 	 * after power-on.
457 	 */
458 	sc->sc_flags &= ~GEM_INITED;
459 	if (ifp->if_flags & IFF_UP)
460 		gem_init_locked(sc);
461 	GEM_UNLOCK(sc);
462 }
463 
464 static inline void
465 gem_rxcksum(struct mbuf *m, uint64_t flags)
466 {
467 	struct ether_header *eh;
468 	struct ip *ip;
469 	struct udphdr *uh;
470 	uint16_t *opts;
471 	int32_t hlen, len, pktlen;
472 	uint32_t temp32;
473 	uint16_t cksum;
474 
475 	pktlen = m->m_pkthdr.len;
476 	if (pktlen < sizeof(struct ether_header) + sizeof(struct ip))
477 		return;
478 	eh = mtod(m, struct ether_header *);
479 	if (eh->ether_type != htons(ETHERTYPE_IP))
480 		return;
481 	ip = (struct ip *)(eh + 1);
482 	if (ip->ip_v != IPVERSION)
483 		return;
484 
485 	hlen = ip->ip_hl << 2;
486 	pktlen -= sizeof(struct ether_header);
487 	if (hlen < sizeof(struct ip))
488 		return;
489 	if (ntohs(ip->ip_len) < hlen)
490 		return;
491 	if (ntohs(ip->ip_len) != pktlen)
492 		return;
493 	if (ip->ip_off & htons(IP_MF | IP_OFFMASK))
494 		return;	/* Cannot handle fragmented packet. */
495 
496 	switch (ip->ip_p) {
497 	case IPPROTO_TCP:
498 		if (pktlen < (hlen + sizeof(struct tcphdr)))
499 			return;
500 		break;
501 	case IPPROTO_UDP:
502 		if (pktlen < (hlen + sizeof(struct udphdr)))
503 			return;
504 		uh = (struct udphdr *)((uint8_t *)ip + hlen);
505 		if (uh->uh_sum == 0)
506 			return; /* no checksum */
507 		break;
508 	default:
509 		return;
510 	}
511 
512 	cksum = ~(flags & GEM_RD_CHECKSUM);
513 	/* checksum fixup for IP options */
514 	len = hlen - sizeof(struct ip);
515 	if (len > 0) {
516 		opts = (uint16_t *)(ip + 1);
517 		for (; len > 0; len -= sizeof(uint16_t), opts++) {
518 			temp32 = cksum - *opts;
519 			temp32 = (temp32 >> 16) + (temp32 & 65535);
520 			cksum = temp32 & 65535;
521 		}
522 	}
523 	m->m_pkthdr.csum_flags |= CSUM_DATA_VALID;
524 	m->m_pkthdr.csum_data = cksum;
525 }
526 
527 static void
528 gem_cddma_callback(void *xsc, bus_dma_segment_t *segs, int nsegs, int error)
529 {
530 	struct gem_softc *sc = xsc;
531 
532 	if (error != 0)
533 		return;
534 	if (nsegs != 1)
535 		panic("%s: bad control buffer segment count", __func__);
536 	sc->sc_cddma = segs[0].ds_addr;
537 }
538 
539 static void
540 gem_tick(void *arg)
541 {
542 	struct gem_softc *sc = arg;
543 	struct ifnet *ifp = sc->sc_ifp;
544 	uint32_t v;
545 
546 	GEM_LOCK_ASSERT(sc, MA_OWNED);
547 
548 	/*
549 	 * Unload collision and error counters.
550 	 */
551 	ifp->if_collisions +=
552 	    GEM_BANK1_READ_4(sc, GEM_MAC_NORM_COLL_CNT) +
553 	    GEM_BANK1_READ_4(sc, GEM_MAC_FIRST_COLL_CNT);
554 	v = GEM_BANK1_READ_4(sc, GEM_MAC_EXCESS_COLL_CNT) +
555 	    GEM_BANK1_READ_4(sc, GEM_MAC_LATE_COLL_CNT);
556 	ifp->if_collisions += v;
557 	ifp->if_oerrors += v;
558 	ifp->if_ierrors +=
559 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_LEN_ERR_CNT) +
560 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_ALIGN_ERR) +
561 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CRC_ERR_CNT) +
562 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CODE_VIOL);
563 
564 	/*
565 	 * Then clear the hardware counters.
566 	 */
567 	GEM_BANK1_WRITE_4(sc, GEM_MAC_NORM_COLL_CNT, 0);
568 	GEM_BANK1_WRITE_4(sc, GEM_MAC_FIRST_COLL_CNT, 0);
569 	GEM_BANK1_WRITE_4(sc, GEM_MAC_EXCESS_COLL_CNT, 0);
570 	GEM_BANK1_WRITE_4(sc, GEM_MAC_LATE_COLL_CNT, 0);
571 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_LEN_ERR_CNT, 0);
572 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_ALIGN_ERR, 0);
573 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CRC_ERR_CNT, 0);
574 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CODE_VIOL, 0);
575 
576 	mii_tick(sc->sc_mii);
577 
578 	if (gem_watchdog(sc) == EJUSTRETURN)
579 		return;
580 
581 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
582 }
583 
584 static int
585 gem_bitwait(struct gem_softc *sc, u_int bank, bus_addr_t r, uint32_t clr,
586     uint32_t set)
587 {
588 	int i;
589 	uint32_t reg;
590 
591 	for (i = GEM_TRIES; i--; DELAY(100)) {
592 		reg = GEM_BANKN_READ_M(bank, 4, sc, r);
593 		if ((reg & clr) == 0 && (reg & set) == set)
594 			return (1);
595 	}
596 	return (0);
597 }
598 
599 static void
600 gem_reset(struct gem_softc *sc)
601 {
602 
603 #ifdef GEM_DEBUG
604 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
605 #endif
606 	gem_reset_rx(sc);
607 	gem_reset_tx(sc);
608 
609 	/* Do a full reset. */
610 	GEM_BANK2_WRITE_4(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX);
611 	GEM_BANK2_BARRIER(sc, GEM_RESET, 4,
612 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
613 	if (!GEM_BANK2_BITWAIT(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX, 0))
614 		device_printf(sc->sc_dev, "cannot reset device\n");
615 }
616 
617 static void
618 gem_rxdrain(struct gem_softc *sc)
619 {
620 	struct gem_rxsoft *rxs;
621 	int i;
622 
623 	for (i = 0; i < GEM_NRXDESC; i++) {
624 		rxs = &sc->sc_rxsoft[i];
625 		if (rxs->rxs_mbuf != NULL) {
626 			bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
627 			    BUS_DMASYNC_POSTREAD);
628 			bus_dmamap_unload(sc->sc_rdmatag, rxs->rxs_dmamap);
629 			m_freem(rxs->rxs_mbuf);
630 			rxs->rxs_mbuf = NULL;
631 		}
632 	}
633 }
634 
635 static void
636 gem_stop(struct ifnet *ifp, int disable)
637 {
638 	struct gem_softc *sc = ifp->if_softc;
639 	struct gem_txsoft *txs;
640 
641 #ifdef GEM_DEBUG
642 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
643 #endif
644 
645 	callout_stop(&sc->sc_tick_ch);
646 #ifdef GEM_RINT_TIMEOUT
647 	callout_stop(&sc->sc_rx_ch);
648 #endif
649 
650 	gem_reset_tx(sc);
651 	gem_reset_rx(sc);
652 
653 	/*
654 	 * Release any queued transmit buffers.
655 	 */
656 	while ((txs = STAILQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
657 		STAILQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
658 		if (txs->txs_ndescs != 0) {
659 			bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
660 			    BUS_DMASYNC_POSTWRITE);
661 			bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
662 			if (txs->txs_mbuf != NULL) {
663 				m_freem(txs->txs_mbuf);
664 				txs->txs_mbuf = NULL;
665 			}
666 		}
667 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
668 	}
669 
670 	if (disable)
671 		gem_rxdrain(sc);
672 
673 	/*
674 	 * Mark the interface down and cancel the watchdog timer.
675 	 */
676 	ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
677 	sc->sc_flags &= ~GEM_LINK;
678 	sc->sc_wdog_timer = 0;
679 }
680 
681 static int
682 gem_reset_rx(struct gem_softc *sc)
683 {
684 
685 	/*
686 	 * Resetting while DMA is in progress can cause a bus hang, so we
687 	 * disable DMA first.
688 	 */
689 	gem_disable_rx(sc);
690 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG, 0);
691 	GEM_BANK1_BARRIER(sc, GEM_RX_CONFIG, 4,
692 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
693 	if (!GEM_BANK1_BITWAIT(sc, GEM_RX_CONFIG, GEM_RX_CONFIG_RXDMA_EN, 0))
694 		device_printf(sc->sc_dev, "cannot disable RX DMA\n");
695 
696 	/* Finally, reset the ERX. */
697 	GEM_BANK2_WRITE_4(sc, GEM_RESET, GEM_RESET_RX);
698 	GEM_BANK2_BARRIER(sc, GEM_RESET, 4,
699 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
700 	if (!GEM_BANK2_BITWAIT(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX,
701 	    0)) {
702 		device_printf(sc->sc_dev, "cannot reset receiver\n");
703 		return (1);
704 	}
705 	return (0);
706 }
707 
708 /*
709  * Reset the receiver DMA engine.
710  *
711  * Intended to be used in case of GEM_INTR_RX_TAG_ERR, GEM_MAC_RX_OVERFLOW
712  * etc in order to reset the receiver DMA engine only and not do a full
713  * reset which amongst others also downs the link and clears the FIFOs.
714  */
715 static void
716 gem_reset_rxdma(struct gem_softc *sc)
717 {
718 	int i;
719 
720 	if (gem_reset_rx(sc) != 0)
721 		return (gem_init_locked(sc));
722 	for (i = 0; i < GEM_NRXDESC; i++)
723 		if (sc->sc_rxsoft[i].rxs_mbuf != NULL)
724 			GEM_UPDATE_RXDESC(sc, i);
725 	sc->sc_rxptr = 0;
726 	GEM_CDSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
727 
728 	/* NOTE: we use only 32-bit DMA addresses here. */
729 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_HI, 0);
730 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_LO, GEM_CDRXADDR(sc, 0));
731 	GEM_BANK1_WRITE_4(sc, GEM_RX_KICK, GEM_NRXDESC - 4);
732 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG,
733 	    gem_ringsize(GEM_NRXDESC /* XXX */) |
734 	    ((ETHER_HDR_LEN + sizeof(struct ip)) <<
735 	    GEM_RX_CONFIG_CXM_START_SHFT) |
736 	    (GEM_THRSH_1024 << GEM_RX_CONFIG_FIFO_THRS_SHIFT) |
737 	    (ETHER_ALIGN << GEM_RX_CONFIG_FBOFF_SHFT));
738 	/* Adjust for the SBus clock probably isn't worth the fuzz. */
739 	GEM_BANK1_WRITE_4(sc, GEM_RX_BLANKING,
740 	    ((6 * (sc->sc_flags & GEM_PCI66) != 0 ? 2 : 1) <<
741 	    GEM_RX_BLANKING_TIME_SHIFT) | 6);
742 	GEM_BANK1_WRITE_4(sc, GEM_RX_PAUSE_THRESH,
743 	    (3 * sc->sc_rxfifosize / 256) |
744 	    ((sc->sc_rxfifosize / 256) << 12));
745 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG,
746 	    GEM_BANK1_READ_4(sc, GEM_RX_CONFIG) | GEM_RX_CONFIG_RXDMA_EN);
747 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_MASK,
748 	    GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT);
749 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG,
750 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG) | GEM_MAC_RX_ENABLE);
751 }
752 
753 static int
754 gem_reset_tx(struct gem_softc *sc)
755 {
756 
757 	/*
758 	 * Resetting while DMA is in progress can cause a bus hang, so we
759 	 * disable DMA first.
760 	 */
761 	gem_disable_tx(sc);
762 	GEM_BANK1_WRITE_4(sc, GEM_TX_CONFIG, 0);
763 	GEM_BANK1_BARRIER(sc, GEM_TX_CONFIG, 4,
764 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
765 	if (!GEM_BANK1_BITWAIT(sc, GEM_TX_CONFIG, GEM_TX_CONFIG_TXDMA_EN, 0))
766 		device_printf(sc->sc_dev, "cannot disable TX DMA\n");
767 
768 	/* Finally, reset the ETX. */
769 	GEM_BANK2_WRITE_4(sc, GEM_RESET, GEM_RESET_TX);
770 	GEM_BANK2_BARRIER(sc, GEM_RESET, 4,
771 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
772 	if (!GEM_BANK2_BITWAIT(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX,
773 	    0)) {
774 		device_printf(sc->sc_dev, "cannot reset transmitter\n");
775 		return (1);
776 	}
777 	return (0);
778 }
779 
780 static int
781 gem_disable_rx(struct gem_softc *sc)
782 {
783 
784 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG,
785 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG) & ~GEM_MAC_RX_ENABLE);
786 	GEM_BANK1_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
787 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
788 	return (GEM_BANK1_BITWAIT(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_ENABLE,
789 	    0));
790 }
791 
792 static int
793 gem_disable_tx(struct gem_softc *sc)
794 {
795 
796 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG,
797 	    GEM_BANK1_READ_4(sc, GEM_MAC_TX_CONFIG) & ~GEM_MAC_TX_ENABLE);
798 	GEM_BANK1_BARRIER(sc, GEM_MAC_TX_CONFIG, 4,
799 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
800 	return (GEM_BANK1_BITWAIT(sc, GEM_MAC_TX_CONFIG, GEM_MAC_TX_ENABLE,
801 	    0));
802 }
803 
804 static int
805 gem_meminit(struct gem_softc *sc)
806 {
807 	struct gem_rxsoft *rxs;
808 	int error, i;
809 
810 	GEM_LOCK_ASSERT(sc, MA_OWNED);
811 
812 	/*
813 	 * Initialize the transmit descriptor ring.
814 	 */
815 	for (i = 0; i < GEM_NTXDESC; i++) {
816 		sc->sc_txdescs[i].gd_flags = 0;
817 		sc->sc_txdescs[i].gd_addr = 0;
818 	}
819 	sc->sc_txfree = GEM_MAXTXFREE;
820 	sc->sc_txnext = 0;
821 	sc->sc_txwin = 0;
822 
823 	/*
824 	 * Initialize the receive descriptor and receive job
825 	 * descriptor rings.
826 	 */
827 	for (i = 0; i < GEM_NRXDESC; i++) {
828 		rxs = &sc->sc_rxsoft[i];
829 		if (rxs->rxs_mbuf == NULL) {
830 			if ((error = gem_add_rxbuf(sc, i)) != 0) {
831 				device_printf(sc->sc_dev,
832 				    "unable to allocate or map RX buffer %d, "
833 				    "error = %d\n", i, error);
834 				/*
835 				 * XXX we should attempt to run with fewer
836 				 * receive buffers instead of just failing.
837 				 */
838 				gem_rxdrain(sc);
839 				return (1);
840 			}
841 		} else
842 			GEM_INIT_RXDESC(sc, i);
843 	}
844 	sc->sc_rxptr = 0;
845 
846 	GEM_CDSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
847 
848 	return (0);
849 }
850 
851 static u_int
852 gem_ringsize(u_int sz)
853 {
854 
855 	switch (sz) {
856 	case 32:
857 		return (GEM_RING_SZ_32);
858 	case 64:
859 		return (GEM_RING_SZ_64);
860 	case 128:
861 		return (GEM_RING_SZ_128);
862 	case 256:
863 		return (GEM_RING_SZ_256);
864 	case 512:
865 		return (GEM_RING_SZ_512);
866 	case 1024:
867 		return (GEM_RING_SZ_1024);
868 	case 2048:
869 		return (GEM_RING_SZ_2048);
870 	case 4096:
871 		return (GEM_RING_SZ_4096);
872 	case 8192:
873 		return (GEM_RING_SZ_8192);
874 	default:
875 		printf("%s: invalid ring size %d\n", __func__, sz);
876 		return (GEM_RING_SZ_32);
877 	}
878 }
879 
880 static void
881 gem_init(void *xsc)
882 {
883 	struct gem_softc *sc = xsc;
884 
885 	GEM_LOCK(sc);
886 	gem_init_locked(sc);
887 	GEM_UNLOCK(sc);
888 }
889 
890 /*
891  * Initialization of interface; set up initialization block
892  * and transmit/receive descriptor rings.
893  */
894 static void
895 gem_init_locked(struct gem_softc *sc)
896 {
897 	struct ifnet *ifp = sc->sc_ifp;
898 	uint32_t v;
899 
900 	GEM_LOCK_ASSERT(sc, MA_OWNED);
901 
902 #ifdef GEM_DEBUG
903 	CTR2(KTR_GEM, "%s: %s: calling stop", device_get_name(sc->sc_dev),
904 	    __func__);
905 #endif
906 	/*
907 	 * Initialization sequence.  The numbered steps below correspond
908 	 * to the sequence outlined in section 6.3.5.1 in the Ethernet
909 	 * Channel Engine manual (part of the PCIO manual).
910 	 * See also the STP2002-STQ document from Sun Microsystems.
911 	 */
912 
913 	/* step 1 & 2.  Reset the Ethernet Channel. */
914 	gem_stop(ifp, 0);
915 	gem_reset(sc);
916 #ifdef GEM_DEBUG
917 	CTR2(KTR_GEM, "%s: %s: restarting", device_get_name(sc->sc_dev),
918 	    __func__);
919 #endif
920 
921 	/* Re-initialize the MIF. */
922 	gem_mifinit(sc);
923 
924 	/* step 3.  Setup data structures in host memory. */
925 	if (gem_meminit(sc) != 0)
926 		return;
927 
928 	/* step 4.  TX MAC registers & counters */
929 	gem_init_regs(sc);
930 
931 	/* step 5.  RX MAC registers & counters */
932 	gem_setladrf(sc);
933 
934 	/* step 6 & 7.  Program Descriptor Ring Base Addresses. */
935 	/* NOTE: we use only 32-bit DMA addresses here. */
936 	GEM_BANK1_WRITE_4(sc, GEM_TX_RING_PTR_HI, 0);
937 	GEM_BANK1_WRITE_4(sc, GEM_TX_RING_PTR_LO, GEM_CDTXADDR(sc, 0));
938 
939 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_HI, 0);
940 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_LO, GEM_CDRXADDR(sc, 0));
941 #ifdef GEM_DEBUG
942 	CTR3(KTR_GEM, "loading RX ring %lx, TX ring %lx, cddma %lx",
943 	    GEM_CDRXADDR(sc, 0), GEM_CDTXADDR(sc, 0), sc->sc_cddma);
944 #endif
945 
946 	/* step 8.  Global Configuration & Interrupt Mask */
947 
948 	/*
949 	 * Set the internal arbitration to "infinite" bursts of the
950 	 * maximum length of 31 * 64 bytes so DMA transfers aren't
951 	 * split up in cache line size chunks.  This greatly improves
952 	 * RX performance.
953 	 * Enable silicon bug workarounds for the Apple variants.
954 	 */
955 	GEM_BANK1_WRITE_4(sc, GEM_CONFIG,
956 	    GEM_CONFIG_TXDMA_LIMIT | GEM_CONFIG_RXDMA_LIMIT |
957 	    ((sc->sc_flags & GEM_PCI) != 0 ? GEM_CONFIG_BURST_INF :
958 	    GEM_CONFIG_BURST_64) | (GEM_IS_APPLE(sc) ?
959 	    GEM_CONFIG_RONPAULBIT | GEM_CONFIG_BUG2FIX : 0));
960 
961 	GEM_BANK1_WRITE_4(sc, GEM_INTMASK,
962 	    ~(GEM_INTR_TX_INTME | GEM_INTR_TX_EMPTY | GEM_INTR_RX_DONE |
963 	    GEM_INTR_RX_NOBUF | GEM_INTR_RX_TAG_ERR | GEM_INTR_PERR |
964 	    GEM_INTR_BERR
965 #ifdef GEM_DEBUG
966 	    | GEM_INTR_PCS | GEM_INTR_MIF
967 #endif
968 	    ));
969 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_MASK,
970 	    GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT);
971 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_MASK,
972 	    GEM_MAC_TX_XMIT_DONE | GEM_MAC_TX_DEFER_EXP |
973 	    GEM_MAC_TX_PEAK_EXP);
974 #ifdef GEM_DEBUG
975 	GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_MASK,
976 	    ~(GEM_MAC_PAUSED | GEM_MAC_PAUSE | GEM_MAC_RESUME));
977 #else
978 	GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_MASK,
979 	    GEM_MAC_PAUSED | GEM_MAC_PAUSE | GEM_MAC_RESUME);
980 #endif
981 
982 	/* step 9.  ETX Configuration: use mostly default values. */
983 
984 	/* Enable DMA. */
985 	v = gem_ringsize(GEM_NTXDESC);
986 	/* Set TX FIFO threshold and enable DMA. */
987 	v |= ((sc->sc_variant == GEM_SUN_ERI ? 0x100 : 0x4ff) << 10) &
988 	    GEM_TX_CONFIG_TXFIFO_TH;
989 	GEM_BANK1_WRITE_4(sc, GEM_TX_CONFIG, v | GEM_TX_CONFIG_TXDMA_EN);
990 
991 	/* step 10.  ERX Configuration */
992 
993 	/* Encode Receive Descriptor ring size. */
994 	v = gem_ringsize(GEM_NRXDESC /* XXX */);
995 	/* RX TCP/UDP checksum offset */
996 	v |= ((ETHER_HDR_LEN + sizeof(struct ip)) <<
997 	    GEM_RX_CONFIG_CXM_START_SHFT);
998 	/* Set RX FIFO threshold, set first byte offset and enable DMA. */
999 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG,
1000 	    v | (GEM_THRSH_1024 << GEM_RX_CONFIG_FIFO_THRS_SHIFT) |
1001 	    (ETHER_ALIGN << GEM_RX_CONFIG_FBOFF_SHFT) |
1002 	    GEM_RX_CONFIG_RXDMA_EN);
1003 
1004 	/* Adjust for the SBus clock probably isn't worth the fuzz. */
1005 	GEM_BANK1_WRITE_4(sc, GEM_RX_BLANKING,
1006 	    ((6 * (sc->sc_flags & GEM_PCI66) != 0 ? 2 : 1) <<
1007 	    GEM_RX_BLANKING_TIME_SHIFT) | 6);
1008 
1009 	/*
1010 	 * The following value is for an OFF Threshold of about 3/4 full
1011 	 * and an ON Threshold of 1/4 full.
1012 	 */
1013 	GEM_BANK1_WRITE_4(sc, GEM_RX_PAUSE_THRESH,
1014 	    (3 * sc->sc_rxfifosize / 256) |
1015 	    ((sc->sc_rxfifosize / 256) << 12));
1016 
1017 	/* step 11.  Configure Media. */
1018 
1019 	/* step 12.  RX_MAC Configuration Register */
1020 	v = GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG);
1021 	v |= GEM_MAC_RX_ENABLE | GEM_MAC_RX_STRIP_CRC;
1022 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, 0);
1023 	GEM_BANK1_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
1024 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1025 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_ENABLE, 0))
1026 		device_printf(sc->sc_dev, "cannot configure RX MAC\n");
1027 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, v);
1028 
1029 	/* step 13.  TX_MAC Configuration Register */
1030 	v = GEM_BANK1_READ_4(sc, GEM_MAC_TX_CONFIG);
1031 	v |= GEM_MAC_TX_ENABLE;
1032 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG, 0);
1033 	GEM_BANK1_BARRIER(sc, GEM_MAC_TX_CONFIG, 4,
1034 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1035 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_TX_CONFIG, GEM_MAC_TX_ENABLE, 0))
1036 		device_printf(sc->sc_dev, "cannot configure TX MAC\n");
1037 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG, v);
1038 
1039 	/* step 14.  Issue Transmit Pending command. */
1040 
1041 	/* step 15.  Give the reciever a swift kick. */
1042 	GEM_BANK1_WRITE_4(sc, GEM_RX_KICK, GEM_NRXDESC - 4);
1043 
1044 	ifp->if_drv_flags |= IFF_DRV_RUNNING;
1045 	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
1046 
1047 	mii_mediachg(sc->sc_mii);
1048 
1049 	/* Start the one second timer. */
1050 	sc->sc_wdog_timer = 0;
1051 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
1052 }
1053 
1054 static int
1055 gem_load_txmbuf(struct gem_softc *sc, struct mbuf **m_head)
1056 {
1057 	bus_dma_segment_t txsegs[GEM_NTXSEGS];
1058 	struct gem_txsoft *txs;
1059 	struct ip *ip;
1060 	struct mbuf *m;
1061 	uint64_t cflags, flags;
1062 	int error, nexttx, nsegs, offset, seg;
1063 
1064 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1065 
1066 	/* Get a work queue entry. */
1067 	if ((txs = STAILQ_FIRST(&sc->sc_txfreeq)) == NULL) {
1068 		/* Ran out of descriptors. */
1069 		return (ENOBUFS);
1070 	}
1071 
1072 	cflags = 0;
1073 	if (((*m_head)->m_pkthdr.csum_flags & sc->sc_csum_features) != 0) {
1074 		if (M_WRITABLE(*m_head) == 0) {
1075 			m = m_dup(*m_head, M_DONTWAIT);
1076 			m_freem(*m_head);
1077 			*m_head = m;
1078 			if (m == NULL)
1079 				return (ENOBUFS);
1080 		}
1081 		offset = sizeof(struct ether_header);
1082 		m = m_pullup(*m_head, offset + sizeof(struct ip));
1083 		if (m == NULL) {
1084 			*m_head = NULL;
1085 			return (ENOBUFS);
1086 		}
1087 		ip = (struct ip *)(mtod(m, caddr_t) + offset);
1088 		offset += (ip->ip_hl << 2);
1089 		cflags = offset << GEM_TD_CXSUM_STARTSHFT |
1090 		    ((offset + m->m_pkthdr.csum_data) <<
1091 		    GEM_TD_CXSUM_STUFFSHFT) | GEM_TD_CXSUM_ENABLE;
1092 		*m_head = m;
1093 	}
1094 
1095 	error = bus_dmamap_load_mbuf_sg(sc->sc_tdmatag, txs->txs_dmamap,
1096 	    *m_head, txsegs, &nsegs, BUS_DMA_NOWAIT);
1097 	if (error == EFBIG) {
1098 		m = m_collapse(*m_head, M_DONTWAIT, GEM_NTXSEGS);
1099 		if (m == NULL) {
1100 			m_freem(*m_head);
1101 			*m_head = NULL;
1102 			return (ENOBUFS);
1103 		}
1104 		*m_head = m;
1105 		error = bus_dmamap_load_mbuf_sg(sc->sc_tdmatag,
1106 		    txs->txs_dmamap, *m_head, txsegs, &nsegs,
1107 		    BUS_DMA_NOWAIT);
1108 		if (error != 0) {
1109 			m_freem(*m_head);
1110 			*m_head = NULL;
1111 			return (error);
1112 		}
1113 	} else if (error != 0)
1114 		return (error);
1115 	/* If nsegs is wrong then the stack is corrupt. */
1116 	KASSERT(nsegs <= GEM_NTXSEGS,
1117 	    ("%s: too many DMA segments (%d)", __func__, nsegs));
1118 	if (nsegs == 0) {
1119 		m_freem(*m_head);
1120 		*m_head = NULL;
1121 		return (EIO);
1122 	}
1123 
1124 	/*
1125 	 * Ensure we have enough descriptors free to describe
1126 	 * the packet.  Note, we always reserve one descriptor
1127 	 * at the end of the ring as a termination point, in
1128 	 * order to prevent wrap-around.
1129 	 */
1130 	if (nsegs > sc->sc_txfree - 1) {
1131 		txs->txs_ndescs = 0;
1132 		bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
1133 		return (ENOBUFS);
1134 	}
1135 
1136 	txs->txs_ndescs = nsegs;
1137 	txs->txs_firstdesc = sc->sc_txnext;
1138 	nexttx = txs->txs_firstdesc;
1139 	for (seg = 0; seg < nsegs; seg++, nexttx = GEM_NEXTTX(nexttx)) {
1140 #ifdef GEM_DEBUG
1141 		CTR6(KTR_GEM,
1142 		    "%s: mapping seg %d (txd %d), len %lx, addr %#lx (%#lx)",
1143 		    __func__, seg, nexttx, txsegs[seg].ds_len,
1144 		    txsegs[seg].ds_addr,
1145 		    GEM_DMA_WRITE(sc, txsegs[seg].ds_addr));
1146 #endif
1147 		sc->sc_txdescs[nexttx].gd_addr =
1148 		    GEM_DMA_WRITE(sc, txsegs[seg].ds_addr);
1149 		KASSERT(txsegs[seg].ds_len < GEM_TD_BUFSIZE,
1150 		    ("%s: segment size too large!", __func__));
1151 		flags = txsegs[seg].ds_len & GEM_TD_BUFSIZE;
1152 		sc->sc_txdescs[nexttx].gd_flags =
1153 		    GEM_DMA_WRITE(sc, flags | cflags);
1154 		txs->txs_lastdesc = nexttx;
1155 	}
1156 
1157 	/* Set EOP on the last descriptor. */
1158 #ifdef GEM_DEBUG
1159 	CTR3(KTR_GEM, "%s: end of packet at segment %d, TX %d",
1160 	    __func__, seg, nexttx);
1161 #endif
1162 	sc->sc_txdescs[txs->txs_lastdesc].gd_flags |=
1163 	    GEM_DMA_WRITE(sc, GEM_TD_END_OF_PACKET);
1164 
1165 	/* Lastly set SOP on the first descriptor. */
1166 #ifdef GEM_DEBUG
1167 	CTR3(KTR_GEM, "%s: start of packet at segment %d, TX %d",
1168 	    __func__, seg, nexttx);
1169 #endif
1170 	if (++sc->sc_txwin > GEM_NTXSEGS * 2 / 3) {
1171 		sc->sc_txwin = 0;
1172 		sc->sc_txdescs[txs->txs_firstdesc].gd_flags |=
1173 		    GEM_DMA_WRITE(sc, GEM_TD_INTERRUPT_ME |
1174 		    GEM_TD_START_OF_PACKET);
1175 	} else
1176 		sc->sc_txdescs[txs->txs_firstdesc].gd_flags |=
1177 		    GEM_DMA_WRITE(sc, GEM_TD_START_OF_PACKET);
1178 
1179 	/* Sync the DMA map. */
1180 	bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
1181 	    BUS_DMASYNC_PREWRITE);
1182 
1183 #ifdef GEM_DEBUG
1184 	CTR4(KTR_GEM, "%s: setting firstdesc=%d, lastdesc=%d, ndescs=%d",
1185 	    __func__, txs->txs_firstdesc, txs->txs_lastdesc,
1186 	    txs->txs_ndescs);
1187 #endif
1188 	STAILQ_REMOVE_HEAD(&sc->sc_txfreeq, txs_q);
1189 	STAILQ_INSERT_TAIL(&sc->sc_txdirtyq, txs, txs_q);
1190 	txs->txs_mbuf = *m_head;
1191 
1192 	sc->sc_txnext = GEM_NEXTTX(txs->txs_lastdesc);
1193 	sc->sc_txfree -= txs->txs_ndescs;
1194 
1195 	return (0);
1196 }
1197 
1198 static void
1199 gem_init_regs(struct gem_softc *sc)
1200 {
1201 	const u_char *laddr = IF_LLADDR(sc->sc_ifp);
1202 
1203 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1204 
1205 	/* These registers are not cleared on reset. */
1206 	if ((sc->sc_flags & GEM_INITED) == 0) {
1207 		/* magic values */
1208 		GEM_BANK1_WRITE_4(sc, GEM_MAC_IPG0, 0);
1209 		GEM_BANK1_WRITE_4(sc, GEM_MAC_IPG1, 8);
1210 		GEM_BANK1_WRITE_4(sc, GEM_MAC_IPG2, 4);
1211 
1212 		/* min frame length */
1213 		GEM_BANK1_WRITE_4(sc, GEM_MAC_MAC_MIN_FRAME, ETHER_MIN_LEN);
1214 		/* max frame length and max burst size */
1215 		GEM_BANK1_WRITE_4(sc, GEM_MAC_MAC_MAX_FRAME,
1216 		    (ETHER_MAX_LEN + ETHER_VLAN_ENCAP_LEN) | (0x2000 << 16));
1217 
1218 		/* more magic values */
1219 		GEM_BANK1_WRITE_4(sc, GEM_MAC_PREAMBLE_LEN, 0x7);
1220 		GEM_BANK1_WRITE_4(sc, GEM_MAC_JAM_SIZE, 0x4);
1221 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ATTEMPT_LIMIT, 0x10);
1222 		GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_TYPE, 0x8088);
1223 
1224 		/* random number seed */
1225 		GEM_BANK1_WRITE_4(sc, GEM_MAC_RANDOM_SEED,
1226 		    ((laddr[5] << 8) | laddr[4]) & 0x3ff);
1227 
1228 		/* secondary MAC address: 0:0:0:0:0:0 */
1229 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR3, 0);
1230 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR4, 0);
1231 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR5, 0);
1232 
1233 		/* MAC control address: 01:80:c2:00:00:01 */
1234 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR6, 0x0001);
1235 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR7, 0xc200);
1236 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR8, 0x0180);
1237 
1238 		/* MAC filter address: 0:0:0:0:0:0 */
1239 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR_FILTER0, 0);
1240 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR_FILTER1, 0);
1241 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR_FILTER2, 0);
1242 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADR_FLT_MASK1_2, 0);
1243 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADR_FLT_MASK0, 0);
1244 
1245 		sc->sc_flags |= GEM_INITED;
1246 	}
1247 
1248 	/* Counters need to be zeroed. */
1249 	GEM_BANK1_WRITE_4(sc, GEM_MAC_NORM_COLL_CNT, 0);
1250 	GEM_BANK1_WRITE_4(sc, GEM_MAC_FIRST_COLL_CNT, 0);
1251 	GEM_BANK1_WRITE_4(sc, GEM_MAC_EXCESS_COLL_CNT, 0);
1252 	GEM_BANK1_WRITE_4(sc, GEM_MAC_LATE_COLL_CNT, 0);
1253 	GEM_BANK1_WRITE_4(sc, GEM_MAC_DEFER_TMR_CNT, 0);
1254 	GEM_BANK1_WRITE_4(sc, GEM_MAC_PEAK_ATTEMPTS, 0);
1255 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_FRAME_COUNT, 0);
1256 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_LEN_ERR_CNT, 0);
1257 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_ALIGN_ERR, 0);
1258 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CRC_ERR_CNT, 0);
1259 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CODE_VIOL, 0);
1260 
1261 	/* Set XOFF PAUSE time. */
1262 	GEM_BANK1_WRITE_4(sc, GEM_MAC_SEND_PAUSE_CMD, 0x1BF0);
1263 
1264 	/* Set the station address. */
1265 	GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR0, (laddr[4] << 8) | laddr[5]);
1266 	GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR1, (laddr[2] << 8) | laddr[3]);
1267 	GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR2, (laddr[0] << 8) | laddr[1]);
1268 
1269 	/* Enable MII outputs. */
1270 	GEM_BANK1_WRITE_4(sc, GEM_MAC_XIF_CONFIG, GEM_MAC_XIF_TX_MII_ENA);
1271 }
1272 
1273 static void
1274 gem_start(struct ifnet *ifp)
1275 {
1276 	struct gem_softc *sc = ifp->if_softc;
1277 
1278 	GEM_LOCK(sc);
1279 	gem_start_locked(ifp);
1280 	GEM_UNLOCK(sc);
1281 }
1282 
1283 static inline void
1284 gem_txkick(struct gem_softc *sc)
1285 {
1286 
1287 	/*
1288 	 * Update the TX kick register.  This register has to point to the
1289 	 * descriptor after the last valid one and for optimum performance
1290 	 * should be incremented in multiples of 4 (the DMA engine fetches/
1291 	 * updates descriptors in batches of 4).
1292 	 */
1293 #ifdef GEM_DEBUG
1294 	CTR3(KTR_GEM, "%s: %s: kicking TX %d",
1295 	    device_get_name(sc->sc_dev), __func__, sc->sc_txnext);
1296 #endif
1297 	GEM_CDSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1298 	GEM_BANK1_WRITE_4(sc, GEM_TX_KICK, sc->sc_txnext);
1299 }
1300 
1301 static void
1302 gem_start_locked(struct ifnet *ifp)
1303 {
1304 	struct gem_softc *sc = ifp->if_softc;
1305 	struct mbuf *m;
1306 	int kicked, ntx;
1307 
1308 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1309 
1310 	if ((ifp->if_drv_flags & (IFF_DRV_RUNNING | IFF_DRV_OACTIVE)) !=
1311 	    IFF_DRV_RUNNING || (sc->sc_flags & GEM_LINK) == 0)
1312 		return;
1313 
1314 #ifdef GEM_DEBUG
1315 	CTR4(KTR_GEM, "%s: %s: txfree %d, txnext %d",
1316 	    device_get_name(sc->sc_dev), __func__, sc->sc_txfree,
1317 	    sc->sc_txnext);
1318 #endif
1319 	ntx = 0;
1320 	kicked = 0;
1321 	for (; !IFQ_DRV_IS_EMPTY(&ifp->if_snd) && sc->sc_txfree > 1;) {
1322 		IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
1323 		if (m == NULL)
1324 			break;
1325 		if (gem_load_txmbuf(sc, &m) != 0) {
1326 			if (m == NULL)
1327 				break;
1328 			ifp->if_drv_flags |= IFF_DRV_OACTIVE;
1329 			IFQ_DRV_PREPEND(&ifp->if_snd, m);
1330 			break;
1331 		}
1332 		if ((sc->sc_txnext % 4) == 0) {
1333 			gem_txkick(sc);
1334 			kicked = 1;
1335 		} else
1336 			kicked = 0;
1337 		ntx++;
1338 		BPF_MTAP(ifp, m);
1339 	}
1340 
1341 	if (ntx > 0) {
1342 		if (kicked == 0)
1343 			gem_txkick(sc);
1344 #ifdef GEM_DEBUG
1345 		CTR2(KTR_GEM, "%s: packets enqueued, OWN on %d",
1346 		    device_get_name(sc->sc_dev), sc->sc_txnext);
1347 #endif
1348 
1349 		/* Set a watchdog timer in case the chip flakes out. */
1350 		sc->sc_wdog_timer = 5;
1351 #ifdef GEM_DEBUG
1352 		CTR3(KTR_GEM, "%s: %s: watchdog %d",
1353 		    device_get_name(sc->sc_dev), __func__,
1354 		    sc->sc_wdog_timer);
1355 #endif
1356 	}
1357 }
1358 
1359 static void
1360 gem_tint(struct gem_softc *sc)
1361 {
1362 	struct ifnet *ifp = sc->sc_ifp;
1363 	struct gem_txsoft *txs;
1364 	int progress;
1365 	uint32_t txlast;
1366 #ifdef GEM_DEBUG
1367 	int i;
1368 
1369 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1370 
1371 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
1372 #endif
1373 
1374 	/*
1375 	 * Go through our TX list and free mbufs for those
1376 	 * frames that have been transmitted.
1377 	 */
1378 	progress = 0;
1379 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD);
1380 	while ((txs = STAILQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
1381 #ifdef GEM_DEBUG
1382 		if ((ifp->if_flags & IFF_DEBUG) != 0) {
1383 			printf("    txsoft %p transmit chain:\n", txs);
1384 			for (i = txs->txs_firstdesc;; i = GEM_NEXTTX(i)) {
1385 				printf("descriptor %d: ", i);
1386 				printf("gd_flags: 0x%016llx\t",
1387 				    (long long)GEM_DMA_READ(sc,
1388 				    sc->sc_txdescs[i].gd_flags));
1389 				printf("gd_addr: 0x%016llx\n",
1390 				    (long long)GEM_DMA_READ(sc,
1391 				    sc->sc_txdescs[i].gd_addr));
1392 				if (i == txs->txs_lastdesc)
1393 					break;
1394 			}
1395 		}
1396 #endif
1397 
1398 		/*
1399 		 * In theory, we could harvest some descriptors before
1400 		 * the ring is empty, but that's a bit complicated.
1401 		 *
1402 		 * GEM_TX_COMPLETION points to the last descriptor
1403 		 * processed + 1.
1404 		 */
1405 		txlast = GEM_BANK1_READ_4(sc, GEM_TX_COMPLETION);
1406 #ifdef GEM_DEBUG
1407 		CTR4(KTR_GEM, "%s: txs->txs_firstdesc = %d, "
1408 		    "txs->txs_lastdesc = %d, txlast = %d",
1409 		    __func__, txs->txs_firstdesc, txs->txs_lastdesc, txlast);
1410 #endif
1411 		if (txs->txs_firstdesc <= txs->txs_lastdesc) {
1412 			if ((txlast >= txs->txs_firstdesc) &&
1413 			    (txlast <= txs->txs_lastdesc))
1414 				break;
1415 		} else {
1416 			/* Ick -- this command wraps. */
1417 			if ((txlast >= txs->txs_firstdesc) ||
1418 			    (txlast <= txs->txs_lastdesc))
1419 				break;
1420 		}
1421 
1422 #ifdef GEM_DEBUG
1423 		CTR1(KTR_GEM, "%s: releasing a descriptor", __func__);
1424 #endif
1425 		STAILQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
1426 
1427 		sc->sc_txfree += txs->txs_ndescs;
1428 
1429 		bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
1430 		    BUS_DMASYNC_POSTWRITE);
1431 		bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
1432 		if (txs->txs_mbuf != NULL) {
1433 			m_freem(txs->txs_mbuf);
1434 			txs->txs_mbuf = NULL;
1435 		}
1436 
1437 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
1438 
1439 		ifp->if_opackets++;
1440 		progress = 1;
1441 	}
1442 
1443 #ifdef GEM_DEBUG
1444 	CTR4(KTR_GEM, "%s: GEM_TX_STATE_MACHINE %x GEM_TX_DATA_PTR %llx "
1445 	    "GEM_TX_COMPLETION %x",
1446 	    __func__, GEM_BANK1_READ_4(sc, GEM_TX_STATE_MACHINE),
1447 	    ((long long)GEM_BANK1_READ_4(sc, GEM_TX_DATA_PTR_HI) << 32) |
1448 	    GEM_BANK1_READ_4(sc, GEM_TX_DATA_PTR_LO),
1449 	    GEM_BANK1_READ_4(sc, GEM_TX_COMPLETION));
1450 #endif
1451 
1452 	if (progress) {
1453 		if (sc->sc_txfree == GEM_NTXDESC - 1)
1454 			sc->sc_txwin = 0;
1455 
1456 		/*
1457 		 * We freed some descriptors, so reset IFF_DRV_OACTIVE
1458 		 * and restart.
1459 		 */
1460 		ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
1461 		if (STAILQ_EMPTY(&sc->sc_txdirtyq))
1462 		    sc->sc_wdog_timer = 0;
1463 		gem_start_locked(ifp);
1464 	}
1465 
1466 #ifdef GEM_DEBUG
1467 	CTR3(KTR_GEM, "%s: %s: watchdog %d",
1468 	    device_get_name(sc->sc_dev), __func__, sc->sc_wdog_timer);
1469 #endif
1470 }
1471 
1472 #ifdef GEM_RINT_TIMEOUT
1473 static void
1474 gem_rint_timeout(void *arg)
1475 {
1476 	struct gem_softc *sc = arg;
1477 
1478 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1479 
1480 	gem_rint(sc);
1481 }
1482 #endif
1483 
1484 static void
1485 gem_rint(struct gem_softc *sc)
1486 {
1487 	struct ifnet *ifp = sc->sc_ifp;
1488 	struct mbuf *m;
1489 	uint64_t rxstat;
1490 	uint32_t rxcomp;
1491 
1492 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1493 
1494 #ifdef GEM_RINT_TIMEOUT
1495 	callout_stop(&sc->sc_rx_ch);
1496 #endif
1497 #ifdef GEM_DEBUG
1498 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
1499 #endif
1500 
1501 	/*
1502 	 * Read the completion register once.  This limits
1503 	 * how long the following loop can execute.
1504 	 */
1505 	rxcomp = GEM_BANK1_READ_4(sc, GEM_RX_COMPLETION);
1506 #ifdef GEM_DEBUG
1507 	CTR3(KTR_GEM, "%s: sc->sc_rxptr %d, complete %d",
1508 	    __func__, sc->sc_rxptr, rxcomp);
1509 #endif
1510 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
1511 	for (; sc->sc_rxptr != rxcomp;) {
1512 		m = sc->sc_rxsoft[sc->sc_rxptr].rxs_mbuf;
1513 		rxstat = GEM_DMA_READ(sc,
1514 		    sc->sc_rxdescs[sc->sc_rxptr].gd_flags);
1515 
1516 		if (rxstat & GEM_RD_OWN) {
1517 #ifdef GEM_RINT_TIMEOUT
1518 			/*
1519 			 * The descriptor is still marked as owned, although
1520 			 * it is supposed to have completed.  This has been
1521 			 * observed on some machines.  Just exiting here
1522 			 * might leave the packet sitting around until another
1523 			 * one arrives to trigger a new interrupt, which is
1524 			 * generally undesirable, so set up a timeout.
1525 			 */
1526 			callout_reset(&sc->sc_rx_ch, GEM_RXOWN_TICKS,
1527 			    gem_rint_timeout, sc);
1528 #endif
1529 			m = NULL;
1530 			goto kickit;
1531 		}
1532 
1533 		if (rxstat & GEM_RD_BAD_CRC) {
1534 			ifp->if_ierrors++;
1535 			device_printf(sc->sc_dev, "receive error: CRC error\n");
1536 			GEM_INIT_RXDESC(sc, sc->sc_rxptr);
1537 			m = NULL;
1538 			goto kickit;
1539 		}
1540 
1541 #ifdef GEM_DEBUG
1542 		if ((ifp->if_flags & IFF_DEBUG) != 0) {
1543 			printf("    rxsoft %p descriptor %d: ",
1544 			    &sc->sc_rxsoft[sc->sc_rxptr], sc->sc_rxptr);
1545 			printf("gd_flags: 0x%016llx\t",
1546 			    (long long)GEM_DMA_READ(sc,
1547 			    sc->sc_rxdescs[sc->sc_rxptr].gd_flags));
1548 			printf("gd_addr: 0x%016llx\n",
1549 			    (long long)GEM_DMA_READ(sc,
1550 			    sc->sc_rxdescs[sc->sc_rxptr].gd_addr));
1551 		}
1552 #endif
1553 
1554 		/*
1555 		 * Allocate a new mbuf cluster.  If that fails, we are
1556 		 * out of memory, and must drop the packet and recycle
1557 		 * the buffer that's already attached to this descriptor.
1558 		 */
1559 		if (gem_add_rxbuf(sc, sc->sc_rxptr) != 0) {
1560 			ifp->if_ierrors++;
1561 			GEM_INIT_RXDESC(sc, sc->sc_rxptr);
1562 			m = NULL;
1563 		}
1564 
1565  kickit:
1566 		/*
1567 		 * Update the RX kick register.  This register has to point
1568 		 * to the descriptor after the last valid one (before the
1569 		 * current batch) and for optimum performance should be
1570 		 * incremented in multiples of 4 (the DMA engine fetches/
1571 		 * updates descriptors in batches of 4).
1572 		 */
1573 		sc->sc_rxptr = GEM_NEXTRX(sc->sc_rxptr);
1574 		if ((sc->sc_rxptr % 4) == 0) {
1575 			GEM_CDSYNC(sc,
1576 			    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1577 			GEM_BANK1_WRITE_4(sc, GEM_RX_KICK,
1578 			    (sc->sc_rxptr + GEM_NRXDESC - 4) &
1579 			    GEM_NRXDESC_MASK);
1580 		}
1581 
1582 		if (m == NULL) {
1583 			if (rxstat & GEM_RD_OWN)
1584 				break;
1585 			continue;
1586 		}
1587 
1588 		ifp->if_ipackets++;
1589 		m->m_data += ETHER_ALIGN; /* first byte offset */
1590 		m->m_pkthdr.rcvif = ifp;
1591 		m->m_pkthdr.len = m->m_len = GEM_RD_BUFLEN(rxstat);
1592 
1593 		if ((ifp->if_capenable & IFCAP_RXCSUM) != 0)
1594 			gem_rxcksum(m, rxstat);
1595 
1596 		/* Pass it on. */
1597 		GEM_UNLOCK(sc);
1598 		(*ifp->if_input)(ifp, m);
1599 		GEM_LOCK(sc);
1600 	}
1601 
1602 #ifdef GEM_DEBUG
1603 	CTR3(KTR_GEM, "%s: done sc->sc_rxptr %d, complete %d", __func__,
1604 	    sc->sc_rxptr, GEM_BANK1_READ_4(sc, GEM_RX_COMPLETION));
1605 #endif
1606 }
1607 
1608 static int
1609 gem_add_rxbuf(struct gem_softc *sc, int idx)
1610 {
1611 	struct gem_rxsoft *rxs = &sc->sc_rxsoft[idx];
1612 	struct mbuf *m;
1613 	bus_dma_segment_t segs[1];
1614 	int error, nsegs;
1615 
1616 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1617 
1618 	m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
1619 	if (m == NULL)
1620 		return (ENOBUFS);
1621 	m->m_len = m->m_pkthdr.len = m->m_ext.ext_size;
1622 
1623 #ifdef GEM_DEBUG
1624 	/* Bzero the packet to check DMA. */
1625 	memset(m->m_ext.ext_buf, 0, m->m_ext.ext_size);
1626 #endif
1627 
1628 	if (rxs->rxs_mbuf != NULL) {
1629 		bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
1630 		    BUS_DMASYNC_POSTREAD);
1631 		bus_dmamap_unload(sc->sc_rdmatag, rxs->rxs_dmamap);
1632 	}
1633 
1634 	error = bus_dmamap_load_mbuf_sg(sc->sc_rdmatag, rxs->rxs_dmamap,
1635 	    m, segs, &nsegs, BUS_DMA_NOWAIT);
1636 	if (error != 0) {
1637 		device_printf(sc->sc_dev,
1638 		    "cannot load RS DMA map %d, error = %d\n", idx, error);
1639 		m_freem(m);
1640 		return (error);
1641 	}
1642 	/* If nsegs is wrong then the stack is corrupt. */
1643 	KASSERT(nsegs == 1,
1644 	    ("%s: too many DMA segments (%d)", __func__, nsegs));
1645 	rxs->rxs_mbuf = m;
1646 	rxs->rxs_paddr = segs[0].ds_addr;
1647 
1648 	bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
1649 	    BUS_DMASYNC_PREREAD);
1650 
1651 	GEM_INIT_RXDESC(sc, idx);
1652 
1653 	return (0);
1654 }
1655 
1656 static void
1657 gem_eint(struct gem_softc *sc, u_int status)
1658 {
1659 
1660 	sc->sc_ifp->if_ierrors++;
1661 	if ((status & GEM_INTR_RX_TAG_ERR) != 0) {
1662 		gem_reset_rxdma(sc);
1663 		return;
1664 	}
1665 
1666 	device_printf(sc->sc_dev, "%s: status 0x%x", __func__, status);
1667 	if ((status & GEM_INTR_BERR) != 0) {
1668 		if ((sc->sc_flags & GEM_PCI) != 0)
1669 			printf(", PCI bus error 0x%x\n",
1670 			    GEM_BANK1_READ_4(sc, GEM_PCI_ERROR_STATUS));
1671 		else
1672 			printf(", SBus error 0x%x\n",
1673 			    GEM_BANK1_READ_4(sc, GEM_SBUS_STATUS));
1674 	}
1675 }
1676 
1677 void
1678 gem_intr(void *v)
1679 {
1680 	struct gem_softc *sc = v;
1681 	uint32_t status, status2;
1682 
1683 	GEM_LOCK(sc);
1684 	status = GEM_BANK1_READ_4(sc, GEM_STATUS);
1685 
1686 #ifdef GEM_DEBUG
1687 	CTR4(KTR_GEM, "%s: %s: cplt %x, status %x",
1688 	    device_get_name(sc->sc_dev), __func__,
1689 	    (status >> GEM_STATUS_TX_COMPLETION_SHFT), (u_int)status);
1690 
1691 	/*
1692 	 * PCS interrupts must be cleared, otherwise no traffic is passed!
1693 	 */
1694 	if ((status & GEM_INTR_PCS) != 0) {
1695 		status2 =
1696 		    GEM_BANK1_READ_4(sc, GEM_MII_INTERRUP_STATUS) |
1697 		    GEM_BANK1_READ_4(sc, GEM_MII_INTERRUP_STATUS);
1698 		if ((status2 & GEM_MII_INTERRUP_LINK) != 0)
1699 			device_printf(sc->sc_dev,
1700 			    "%s: PCS link status changed\n", __func__);
1701 	}
1702 	if ((status & GEM_MAC_CONTROL_STATUS) != 0) {
1703 		status2 = GEM_BANK1_READ_4(sc, GEM_MAC_CONTROL_STATUS);
1704 		if ((status2 & GEM_MAC_PAUSED) != 0)
1705 			device_printf(sc->sc_dev,
1706 			    "%s: PAUSE received (PAUSE time %d slots)\n",
1707 			    __func__, GEM_MAC_PAUSE_TIME(status2));
1708 		if ((status2 & GEM_MAC_PAUSE) != 0)
1709 			device_printf(sc->sc_dev,
1710 			    "%s: transited to PAUSE state\n", __func__);
1711 		if ((status2 & GEM_MAC_RESUME) != 0)
1712 			device_printf(sc->sc_dev,
1713 			    "%s: transited to non-PAUSE state\n", __func__);
1714 	}
1715 	if ((status & GEM_INTR_MIF) != 0)
1716 		device_printf(sc->sc_dev, "%s: MIF interrupt\n", __func__);
1717 #endif
1718 
1719 	if (__predict_false(status &
1720 	    (GEM_INTR_RX_TAG_ERR | GEM_INTR_PERR | GEM_INTR_BERR)) != 0)
1721 		gem_eint(sc, status);
1722 
1723 	if ((status & (GEM_INTR_RX_DONE | GEM_INTR_RX_NOBUF)) != 0)
1724 		gem_rint(sc);
1725 
1726 	if ((status & (GEM_INTR_TX_EMPTY | GEM_INTR_TX_INTME)) != 0)
1727 		gem_tint(sc);
1728 
1729 	if (__predict_false((status & GEM_INTR_TX_MAC) != 0)) {
1730 		status2 = GEM_BANK1_READ_4(sc, GEM_MAC_TX_STATUS);
1731 		if ((status2 &
1732 		    ~(GEM_MAC_TX_XMIT_DONE | GEM_MAC_TX_DEFER_EXP |
1733 		    GEM_MAC_TX_PEAK_EXP)) != 0)
1734 			device_printf(sc->sc_dev,
1735 			    "MAC TX fault, status %x\n", status2);
1736 		if ((status2 &
1737 		    (GEM_MAC_TX_UNDERRUN | GEM_MAC_TX_PKT_TOO_LONG)) != 0) {
1738 			sc->sc_ifp->if_oerrors++;
1739 			gem_init_locked(sc);
1740 		}
1741 	}
1742 	if (__predict_false((status & GEM_INTR_RX_MAC) != 0)) {
1743 		status2 = GEM_BANK1_READ_4(sc, GEM_MAC_RX_STATUS);
1744 		/*
1745 		 * At least with GEM_SUN_GEM and some GEM_SUN_ERI
1746 		 * revisions GEM_MAC_RX_OVERFLOW happen often due to a
1747 		 * silicon bug so handle them silently.  Moreover, it's
1748 		 * likely that the receiver has hung so we reset it.
1749 		 */
1750 		if ((status2 & GEM_MAC_RX_OVERFLOW) != 0) {
1751 			sc->sc_ifp->if_ierrors++;
1752 			gem_reset_rxdma(sc);
1753 		} else if ((status2 &
1754 		    ~(GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT)) != 0)
1755 			device_printf(sc->sc_dev,
1756 			    "MAC RX fault, status %x\n", status2);
1757 	}
1758 	GEM_UNLOCK(sc);
1759 }
1760 
1761 static int
1762 gem_watchdog(struct gem_softc *sc)
1763 {
1764 	struct ifnet *ifp = sc->sc_ifp;
1765 
1766 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1767 
1768 #ifdef GEM_DEBUG
1769 	CTR4(KTR_GEM,
1770 	    "%s: GEM_RX_CONFIG %x GEM_MAC_RX_STATUS %x GEM_MAC_RX_CONFIG %x",
1771 	    __func__, GEM_BANK1_READ_4(sc, GEM_RX_CONFIG),
1772 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_STATUS),
1773 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG));
1774 	CTR4(KTR_GEM,
1775 	    "%s: GEM_TX_CONFIG %x GEM_MAC_TX_STATUS %x GEM_MAC_TX_CONFIG %x",
1776 	    __func__, GEM_BANK1_READ_4(sc, GEM_TX_CONFIG),
1777 	    GEM_BANK1_READ_4(sc, GEM_MAC_TX_STATUS),
1778 	    GEM_BANK1_READ_4(sc, GEM_MAC_TX_CONFIG));
1779 #endif
1780 
1781 	if (sc->sc_wdog_timer == 0 || --sc->sc_wdog_timer != 0)
1782 		return (0);
1783 
1784 	if ((sc->sc_flags & GEM_LINK) != 0)
1785 		device_printf(sc->sc_dev, "device timeout\n");
1786 	else if (bootverbose)
1787 		device_printf(sc->sc_dev, "device timeout (no link)\n");
1788 	++ifp->if_oerrors;
1789 
1790 	/* Try to get more packets going. */
1791 	gem_init_locked(sc);
1792 	gem_start_locked(ifp);
1793 	return (EJUSTRETURN);
1794 }
1795 
1796 static void
1797 gem_mifinit(struct gem_softc *sc)
1798 {
1799 
1800 	/* Configure the MIF in frame mode. */
1801 	GEM_BANK1_WRITE_4(sc, GEM_MIF_CONFIG,
1802 	    GEM_BANK1_READ_4(sc, GEM_MIF_CONFIG) & ~GEM_MIF_CONFIG_BB_ENA);
1803 }
1804 
1805 /*
1806  * MII interface
1807  *
1808  * The MII interface supports at least three different operating modes:
1809  *
1810  * Bitbang mode is implemented using data, clock and output enable registers.
1811  *
1812  * Frame mode is implemented by loading a complete frame into the frame
1813  * register and polling the valid bit for completion.
1814  *
1815  * Polling mode uses the frame register but completion is indicated by
1816  * an interrupt.
1817  *
1818  */
1819 int
1820 gem_mii_readreg(device_t dev, int phy, int reg)
1821 {
1822 	struct gem_softc *sc;
1823 	int n;
1824 	uint32_t v;
1825 
1826 #ifdef GEM_DEBUG_PHY
1827 	printf("%s: phy %d reg %d\n", __func__, phy, reg);
1828 #endif
1829 
1830 	sc = device_get_softc(dev);
1831 	if (sc->sc_phyad != -1 && phy != sc->sc_phyad)
1832 		return (0);
1833 
1834 	if ((sc->sc_flags & GEM_SERDES) != 0) {
1835 		switch (reg) {
1836 		case MII_BMCR:
1837 			reg = GEM_MII_CONTROL;
1838 			break;
1839 		case MII_BMSR:
1840 			reg = GEM_MII_STATUS;
1841 			break;
1842 		case MII_PHYIDR1:
1843 		case MII_PHYIDR2:
1844 			return (0);
1845 		case MII_ANAR:
1846 			reg = GEM_MII_ANAR;
1847 			break;
1848 		case MII_ANLPAR:
1849 			reg = GEM_MII_ANLPAR;
1850 			break;
1851 		case MII_EXTSR:
1852 			return (EXTSR_1000XFDX | EXTSR_1000XHDX);
1853 		default:
1854 			device_printf(sc->sc_dev,
1855 			    "%s: unhandled register %d\n", __func__, reg);
1856 			return (0);
1857 		}
1858 		return (GEM_BANK1_READ_4(sc, reg));
1859 	}
1860 
1861 	/* Construct the frame command. */
1862 	v = GEM_MIF_FRAME_READ |
1863 	    (phy << GEM_MIF_PHY_SHIFT) |
1864 	    (reg << GEM_MIF_REG_SHIFT);
1865 
1866 	GEM_BANK1_WRITE_4(sc, GEM_MIF_FRAME, v);
1867 	GEM_BANK1_BARRIER(sc, GEM_MIF_FRAME, 4,
1868 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1869 	for (n = 0; n < 100; n++) {
1870 		DELAY(1);
1871 		v = GEM_BANK1_READ_4(sc, GEM_MIF_FRAME);
1872 		if (v & GEM_MIF_FRAME_TA0)
1873 			return (v & GEM_MIF_FRAME_DATA);
1874 	}
1875 
1876 	device_printf(sc->sc_dev, "%s: timed out\n", __func__);
1877 	return (0);
1878 }
1879 
1880 int
1881 gem_mii_writereg(device_t dev, int phy, int reg, int val)
1882 {
1883 	struct gem_softc *sc;
1884 	int n;
1885 	uint32_t v;
1886 
1887 #ifdef GEM_DEBUG_PHY
1888 	printf("%s: phy %d reg %d val %x\n", phy, reg, val, __func__);
1889 #endif
1890 
1891 	sc = device_get_softc(dev);
1892 	if (sc->sc_phyad != -1 && phy != sc->sc_phyad)
1893 		return (0);
1894 
1895 	if ((sc->sc_flags & GEM_SERDES) != 0) {
1896 		switch (reg) {
1897 		case MII_BMSR:
1898 			reg = GEM_MII_STATUS;
1899 			break;
1900 		case MII_BMCR:
1901 			reg = GEM_MII_CONTROL;
1902 			if ((val & GEM_MII_CONTROL_RESET) == 0)
1903 				break;
1904 			GEM_BANK1_WRITE_4(sc, GEM_MII_CONTROL, val);
1905 			GEM_BANK1_BARRIER(sc, GEM_MII_CONTROL, 4,
1906 			    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1907 			if (!GEM_BANK1_BITWAIT(sc, GEM_MII_CONTROL,
1908 			    GEM_MII_CONTROL_RESET, 0))
1909 				device_printf(sc->sc_dev,
1910 				    "cannot reset PCS\n");
1911 			/* FALLTHROUGH */
1912 		case MII_ANAR:
1913 			GEM_BANK1_WRITE_4(sc, GEM_MII_CONFIG, 0);
1914 			GEM_BANK1_BARRIER(sc, GEM_MII_CONFIG, 4,
1915 			    BUS_SPACE_BARRIER_WRITE);
1916 			GEM_BANK1_WRITE_4(sc, GEM_MII_ANAR, val);
1917 			GEM_BANK1_WRITE_4(sc, GEM_MII_SLINK_CONTROL,
1918 			    GEM_MII_SLINK_LOOPBACK | GEM_MII_SLINK_EN_SYNC_D);
1919 			GEM_BANK1_WRITE_4(sc, GEM_MII_CONFIG,
1920 			    GEM_MII_CONFIG_ENABLE);
1921 			return (0);
1922 		case MII_ANLPAR:
1923 			reg = GEM_MII_ANLPAR;
1924 			break;
1925 		default:
1926 			device_printf(sc->sc_dev,
1927 			    "%s: unhandled register %d\n", __func__, reg);
1928 			return (0);
1929 		}
1930 		GEM_BANK1_WRITE_4(sc, reg, val);
1931 		return (0);
1932 	}
1933 
1934 	/* Construct the frame command. */
1935 	v = GEM_MIF_FRAME_WRITE |
1936 	    (phy << GEM_MIF_PHY_SHIFT) |
1937 	    (reg << GEM_MIF_REG_SHIFT) |
1938 	    (val & GEM_MIF_FRAME_DATA);
1939 
1940 	GEM_BANK1_WRITE_4(sc, GEM_MIF_FRAME, v);
1941 	GEM_BANK1_BARRIER(sc, GEM_MIF_FRAME, 4,
1942 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1943 	for (n = 0; n < 100; n++) {
1944 		DELAY(1);
1945 		v = GEM_BANK1_READ_4(sc, GEM_MIF_FRAME);
1946 		if (v & GEM_MIF_FRAME_TA0)
1947 			return (1);
1948 	}
1949 
1950 	device_printf(sc->sc_dev, "%s: timed out\n", __func__);
1951 	return (0);
1952 }
1953 
1954 void
1955 gem_mii_statchg(device_t dev)
1956 {
1957 	struct gem_softc *sc;
1958 	int gigabit;
1959 	uint32_t rxcfg, txcfg, v;
1960 
1961 	sc = device_get_softc(dev);
1962 
1963 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1964 
1965 #ifdef GEM_DEBUG
1966 	if ((sc->sc_ifp->if_flags & IFF_DEBUG) != 0)
1967 		device_printf(sc->sc_dev, "%s: status change: PHY = %d\n",
1968 		    __func__, sc->sc_phyad);
1969 #endif
1970 
1971 	if ((sc->sc_mii->mii_media_status & IFM_ACTIVE) != 0 &&
1972 	    IFM_SUBTYPE(sc->sc_mii->mii_media_active) != IFM_NONE)
1973 		sc->sc_flags |= GEM_LINK;
1974 	else
1975 		sc->sc_flags &= ~GEM_LINK;
1976 
1977 	switch (IFM_SUBTYPE(sc->sc_mii->mii_media_active)) {
1978 	case IFM_1000_SX:
1979 	case IFM_1000_LX:
1980 	case IFM_1000_CX:
1981 	case IFM_1000_T:
1982 		gigabit = 1;
1983 		break;
1984 	default:
1985 		gigabit = 0;
1986 	}
1987 
1988 	/*
1989 	 * The configuration done here corresponds to the steps F) and
1990 	 * G) and as far as enabling of RX and TX MAC goes also step H)
1991 	 * of the initialization sequence outlined in section 3.2.1 of
1992 	 * the GEM Gigabit Ethernet ASIC Specification.
1993 	 */
1994 
1995 	rxcfg = GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG);
1996 	rxcfg &= ~(GEM_MAC_RX_CARR_EXTEND | GEM_MAC_RX_ENABLE);
1997 	txcfg = GEM_MAC_TX_ENA_IPG0 | GEM_MAC_TX_NGU | GEM_MAC_TX_NGU_LIMIT;
1998 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) != 0)
1999 		txcfg |= GEM_MAC_TX_IGN_CARRIER | GEM_MAC_TX_IGN_COLLIS;
2000 	else if (gigabit != 0) {
2001 		rxcfg |= GEM_MAC_RX_CARR_EXTEND;
2002 		txcfg |= GEM_MAC_TX_CARR_EXTEND;
2003 	}
2004 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG, 0);
2005 	GEM_BANK1_BARRIER(sc, GEM_MAC_TX_CONFIG, 4,
2006 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
2007 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_TX_CONFIG, GEM_MAC_TX_ENABLE, 0))
2008 		device_printf(sc->sc_dev, "cannot disable TX MAC\n");
2009 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG, txcfg);
2010 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, 0);
2011 	GEM_BANK1_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
2012 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
2013 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_ENABLE, 0))
2014 		device_printf(sc->sc_dev, "cannot disable RX MAC\n");
2015 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, rxcfg);
2016 
2017 	v = GEM_BANK1_READ_4(sc, GEM_MAC_CONTROL_CONFIG) &
2018 	    ~(GEM_MAC_CC_RX_PAUSE | GEM_MAC_CC_TX_PAUSE);
2019 #ifdef notyet
2020 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
2021 	    IFM_ETH_RXPAUSE) != 0)
2022 		v |= GEM_MAC_CC_RX_PAUSE;
2023 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
2024 	    IFM_ETH_TXPAUSE) != 0)
2025 		v |= GEM_MAC_CC_TX_PAUSE;
2026 #endif
2027 	GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_CONFIG, v);
2028 
2029 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) == 0 &&
2030 	    gigabit != 0)
2031 		GEM_BANK1_WRITE_4(sc, GEM_MAC_SLOT_TIME,
2032 		    GEM_MAC_SLOT_TIME_CARR_EXTEND);
2033 	else
2034 		GEM_BANK1_WRITE_4(sc, GEM_MAC_SLOT_TIME,
2035 		    GEM_MAC_SLOT_TIME_NORMAL);
2036 
2037 	/* XIF Configuration */
2038 	v = GEM_MAC_XIF_LINK_LED;
2039 	v |= GEM_MAC_XIF_TX_MII_ENA;
2040 	if ((sc->sc_flags & GEM_SERDES) == 0) {
2041 		if ((GEM_BANK1_READ_4(sc, GEM_MIF_CONFIG) &
2042 		    GEM_MIF_CONFIG_PHY_SEL) != 0) {
2043 			/* External MII needs echo disable if half duplex. */
2044 			if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
2045 			    IFM_FDX) == 0)
2046 				v |= GEM_MAC_XIF_ECHO_DISABL;
2047 		} else
2048 			/*
2049 			 * Internal MII needs buffer enable.
2050 			 * XXX buffer enable makes only sense for an
2051 			 * external PHY.
2052 			 */
2053 			v |= GEM_MAC_XIF_MII_BUF_ENA;
2054 	}
2055 	if (gigabit != 0)
2056 		v |= GEM_MAC_XIF_GMII_MODE;
2057 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) != 0)
2058 		v |= GEM_MAC_XIF_FDPLX_LED;
2059 	GEM_BANK1_WRITE_4(sc, GEM_MAC_XIF_CONFIG, v);
2060 
2061 	if ((sc->sc_ifp->if_drv_flags & IFF_DRV_RUNNING) != 0 &&
2062 	    (sc->sc_flags & GEM_LINK) != 0) {
2063 		GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG,
2064 		    txcfg | GEM_MAC_TX_ENABLE);
2065 		GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG,
2066 		    rxcfg | GEM_MAC_RX_ENABLE);
2067 	}
2068 }
2069 
2070 int
2071 gem_mediachange(struct ifnet *ifp)
2072 {
2073 	struct gem_softc *sc = ifp->if_softc;
2074 	int error;
2075 
2076 	/* XXX add support for serial media. */
2077 
2078 	GEM_LOCK(sc);
2079 	error = mii_mediachg(sc->sc_mii);
2080 	GEM_UNLOCK(sc);
2081 	return (error);
2082 }
2083 
2084 void
2085 gem_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
2086 {
2087 	struct gem_softc *sc = ifp->if_softc;
2088 
2089 	GEM_LOCK(sc);
2090 	if ((ifp->if_flags & IFF_UP) == 0) {
2091 		GEM_UNLOCK(sc);
2092 		return;
2093 	}
2094 
2095 	mii_pollstat(sc->sc_mii);
2096 	ifmr->ifm_active = sc->sc_mii->mii_media_active;
2097 	ifmr->ifm_status = sc->sc_mii->mii_media_status;
2098 	GEM_UNLOCK(sc);
2099 }
2100 
2101 static int
2102 gem_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
2103 {
2104 	struct gem_softc *sc = ifp->if_softc;
2105 	struct ifreq *ifr = (struct ifreq *)data;
2106 	int error;
2107 
2108 	error = 0;
2109 	switch (cmd) {
2110 	case SIOCSIFFLAGS:
2111 		GEM_LOCK(sc);
2112 		if ((ifp->if_flags & IFF_UP) != 0) {
2113 			if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0 &&
2114 			    ((ifp->if_flags ^ sc->sc_ifflags) &
2115 			    (IFF_ALLMULTI | IFF_PROMISC)) != 0)
2116 				gem_setladrf(sc);
2117 			else
2118 				gem_init_locked(sc);
2119 		} else if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
2120 			gem_stop(ifp, 0);
2121 		if ((ifp->if_flags & IFF_LINK0) != 0)
2122 			sc->sc_csum_features |= CSUM_UDP;
2123 		else
2124 			sc->sc_csum_features &= ~CSUM_UDP;
2125 		if ((ifp->if_capenable & IFCAP_TXCSUM) != 0)
2126 			ifp->if_hwassist = sc->sc_csum_features;
2127 		sc->sc_ifflags = ifp->if_flags;
2128 		GEM_UNLOCK(sc);
2129 		break;
2130 	case SIOCADDMULTI:
2131 	case SIOCDELMULTI:
2132 		GEM_LOCK(sc);
2133 		gem_setladrf(sc);
2134 		GEM_UNLOCK(sc);
2135 		break;
2136 	case SIOCGIFMEDIA:
2137 	case SIOCSIFMEDIA:
2138 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii->mii_media, cmd);
2139 		break;
2140 	case SIOCSIFCAP:
2141 		GEM_LOCK(sc);
2142 		ifp->if_capenable = ifr->ifr_reqcap;
2143 		if ((ifp->if_capenable & IFCAP_TXCSUM) != 0)
2144 			ifp->if_hwassist = sc->sc_csum_features;
2145 		else
2146 			ifp->if_hwassist = 0;
2147 		GEM_UNLOCK(sc);
2148 		break;
2149 	default:
2150 		error = ether_ioctl(ifp, cmd, data);
2151 		break;
2152 	}
2153 
2154 	return (error);
2155 }
2156 
2157 static void
2158 gem_setladrf(struct gem_softc *sc)
2159 {
2160 	struct ifnet *ifp = sc->sc_ifp;
2161 	struct ifmultiaddr *inm;
2162 	int i;
2163 	uint32_t hash[16];
2164 	uint32_t crc, v;
2165 
2166 	GEM_LOCK_ASSERT(sc, MA_OWNED);
2167 
2168 	/* Get the current RX configuration. */
2169 	v = GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG);
2170 
2171 	/*
2172 	 * Turn off promiscuous mode, promiscuous group mode (all multicast),
2173 	 * and hash filter.  Depending on the case, the right bit will be
2174 	 * enabled.
2175 	 */
2176 	v &= ~(GEM_MAC_RX_PROMISCUOUS | GEM_MAC_RX_HASH_FILTER |
2177 	    GEM_MAC_RX_PROMISC_GRP);
2178 
2179 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, v);
2180 	GEM_BANK1_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
2181 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
2182 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_HASH_FILTER,
2183 	    0))
2184 		device_printf(sc->sc_dev, "cannot disable RX hash filter\n");
2185 
2186 	if ((ifp->if_flags & IFF_PROMISC) != 0) {
2187 		v |= GEM_MAC_RX_PROMISCUOUS;
2188 		goto chipit;
2189 	}
2190 	if ((ifp->if_flags & IFF_ALLMULTI) != 0) {
2191 		v |= GEM_MAC_RX_PROMISC_GRP;
2192 		goto chipit;
2193 	}
2194 
2195 	/*
2196 	 * Set up multicast address filter by passing all multicast
2197 	 * addresses through a crc generator, and then using the high
2198 	 * order 8 bits as an index into the 256 bit logical address
2199 	 * filter.  The high order 4 bits selects the word, while the
2200 	 * other 4 bits select the bit within the word (where bit 0
2201 	 * is the MSB).
2202 	 */
2203 
2204 	/* Clear the hash table. */
2205 	memset(hash, 0, sizeof(hash));
2206 
2207 	if_maddr_rlock(ifp);
2208 	TAILQ_FOREACH(inm, &ifp->if_multiaddrs, ifma_link) {
2209 		if (inm->ifma_addr->sa_family != AF_LINK)
2210 			continue;
2211 		crc = ether_crc32_le(LLADDR((struct sockaddr_dl *)
2212 		    inm->ifma_addr), ETHER_ADDR_LEN);
2213 
2214 		/* We just want the 8 most significant bits. */
2215 		crc >>= 24;
2216 
2217 		/* Set the corresponding bit in the filter. */
2218 		hash[crc >> 4] |= 1 << (15 - (crc & 15));
2219 	}
2220 	if_maddr_runlock(ifp);
2221 
2222 	v |= GEM_MAC_RX_HASH_FILTER;
2223 
2224 	/* Now load the hash table into the chip (if we are using it). */
2225 	for (i = 0; i < 16; i++)
2226 		GEM_BANK1_WRITE_4(sc,
2227 		    GEM_MAC_HASH0 + i * (GEM_MAC_HASH1 - GEM_MAC_HASH0),
2228 		    hash[i]);
2229 
2230  chipit:
2231 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, v);
2232 }
2233