xref: /freebsd/sys/dev/gem/if_gem.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (C) 2001 Eduardo Horvath.
5  * Copyright (c) 2001-2003 Thomas Moestl
6  * Copyright (c) 2007 Marius Strobl <marius@FreeBSD.org>
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR  ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR  BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  *	from: NetBSD: gem.c,v 1.21 2002/06/01 23:50:58 lukem Exp
31  */
32 
33 #include <sys/cdefs.h>
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_var.h>
65 #include <net/if_arp.h>
66 #include <net/if_dl.h>
67 #include <net/if_media.h>
68 #include <net/if_types.h>
69 #include <net/if_vlan_var.h>
70 
71 #include <netinet/in.h>
72 #include <netinet/in_systm.h>
73 #include <netinet/ip.h>
74 #include <netinet/tcp.h>
75 #include <netinet/udp.h>
76 
77 #include <machine/bus.h>
78 
79 #include <dev/mii/mii.h>
80 #include <dev/mii/miivar.h>
81 
82 #include <dev/gem/if_gemreg.h>
83 #include <dev/gem/if_gemvar.h>
84 
85 CTASSERT(powerof2(GEM_NRXDESC) && GEM_NRXDESC >= 32 && GEM_NRXDESC <= 8192);
86 CTASSERT(powerof2(GEM_NTXDESC) && GEM_NTXDESC >= 32 && GEM_NTXDESC <= 8192);
87 
88 #define	GEM_TRIES	10000
89 
90 /*
91  * The hardware supports basic TCP/UDP checksum offloading.  However,
92  * the hardware doesn't compensate the checksum for UDP datagram which
93  * can yield to 0x0.  As a safe guard, UDP checksum offload is disabled
94  * by default.  It can be reactivated by setting special link option
95  * link0 with ifconfig(8).
96  */
97 #define	GEM_CSUM_FEATURES	(CSUM_TCP)
98 
99 static int	gem_add_rxbuf(struct gem_softc *sc, int idx);
100 static int	gem_bitwait(struct gem_softc *sc, bus_addr_t r, uint32_t clr,
101 		    uint32_t set);
102 static void	gem_cddma_callback(void *xsc, bus_dma_segment_t *segs,
103 		    int nsegs, int error);
104 static int	gem_disable_rx(struct gem_softc *sc);
105 static int	gem_disable_tx(struct gem_softc *sc);
106 static void	gem_eint(struct gem_softc *sc, u_int status);
107 static void	gem_init(void *xsc);
108 static void	gem_init_locked(struct gem_softc *sc);
109 static void	gem_init_regs(struct gem_softc *sc);
110 static int	gem_ioctl(if_t ifp, u_long cmd, caddr_t data);
111 static int	gem_load_txmbuf(struct gem_softc *sc, struct mbuf **m_head);
112 static int	gem_meminit(struct gem_softc *sc);
113 static void	gem_mifinit(struct gem_softc *sc);
114 static void	gem_reset(struct gem_softc *sc);
115 static int	gem_reset_rx(struct gem_softc *sc);
116 static void	gem_reset_rxdma(struct gem_softc *sc);
117 static int	gem_reset_tx(struct gem_softc *sc);
118 static u_int	gem_ringsize(u_int sz);
119 static void	gem_rint(struct gem_softc *sc);
120 #ifdef GEM_RINT_TIMEOUT
121 static void	gem_rint_timeout(void *arg);
122 #endif
123 static inline void gem_rxcksum(struct mbuf *m, uint64_t flags);
124 static void	gem_rxdrain(struct gem_softc *sc);
125 static void	gem_setladrf(struct gem_softc *sc);
126 static void	gem_start(if_t ifp);
127 static void	gem_start_locked(if_t ifp);
128 static void	gem_stop(if_t ifp, int disable);
129 static void	gem_tick(void *arg);
130 static void	gem_tint(struct gem_softc *sc);
131 static inline void gem_txkick(struct gem_softc *sc);
132 static int	gem_watchdog(struct gem_softc *sc);
133 
134 DRIVER_MODULE(miibus, gem, miibus_driver, 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 int
143 gem_attach(struct gem_softc *sc)
144 {
145 	struct gem_txsoft *txs;
146 	if_t ifp;
147 	int error, i, phy;
148 	uint32_t v;
149 
150 	if (bootverbose)
151 		device_printf(sc->sc_dev, "flags=0x%x\n", sc->sc_flags);
152 
153 	/* Set up ifnet structure. */
154 	ifp = sc->sc_ifp = if_alloc(IFT_ETHER);
155 	if (ifp == NULL)
156 		return (ENOSPC);
157 	sc->sc_csum_features = GEM_CSUM_FEATURES;
158 	if_setsoftc(ifp, sc);
159 	if_initname(ifp, device_get_name(sc->sc_dev),
160 	    device_get_unit(sc->sc_dev));
161 	if_setflags(ifp, IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST);
162 	if_setstartfn(ifp, gem_start);
163 	if_setioctlfn(ifp, gem_ioctl);
164 	if_setinitfn(ifp, gem_init);
165 	if_setsendqlen(ifp, GEM_TXQUEUELEN);
166 	if_setsendqready(ifp);
167 
168 	callout_init_mtx(&sc->sc_tick_ch, &sc->sc_mtx, 0);
169 #ifdef GEM_RINT_TIMEOUT
170 	callout_init_mtx(&sc->sc_rx_ch, &sc->sc_mtx, 0);
171 #endif
172 
173 	/* Make sure the chip is stopped. */
174 	gem_reset(sc);
175 
176 	error = bus_dma_tag_create(bus_get_dma_tag(sc->sc_dev), 1, 0,
177 	    BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL,
178 	    BUS_SPACE_MAXSIZE_32BIT, 0, BUS_SPACE_MAXSIZE_32BIT, 0, NULL,
179 	    NULL, &sc->sc_pdmatag);
180 	if (error != 0)
181 		goto fail_ifnet;
182 
183 	error = bus_dma_tag_create(sc->sc_pdmatag, 1, 0,
184 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL, MCLBYTES,
185 	    1, MCLBYTES, BUS_DMA_ALLOCNOW, NULL, NULL, &sc->sc_rdmatag);
186 	if (error != 0)
187 		goto fail_ptag;
188 
189 	error = bus_dma_tag_create(sc->sc_pdmatag, 1, 0,
190 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
191 	    MCLBYTES * GEM_NTXSEGS, GEM_NTXSEGS, MCLBYTES,
192 	    BUS_DMA_ALLOCNOW, NULL, NULL, &sc->sc_tdmatag);
193 	if (error != 0)
194 		goto fail_rtag;
195 
196 	error = bus_dma_tag_create(sc->sc_pdmatag, PAGE_SIZE, 0,
197 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
198 	    sizeof(struct gem_control_data), 1,
199 	    sizeof(struct gem_control_data), 0,
200 	    NULL, NULL, &sc->sc_cdmatag);
201 	if (error != 0)
202 		goto fail_ttag;
203 
204 	/*
205 	 * Allocate the control data structures, create and load the
206 	 * DMA map for it.
207 	 */
208 	if ((error = bus_dmamem_alloc(sc->sc_cdmatag,
209 	    (void **)&sc->sc_control_data,
210 	    BUS_DMA_WAITOK | BUS_DMA_COHERENT | BUS_DMA_ZERO,
211 	    &sc->sc_cddmamap)) != 0) {
212 		device_printf(sc->sc_dev,
213 		    "unable to allocate control data, error = %d\n", error);
214 		goto fail_ctag;
215 	}
216 
217 	sc->sc_cddma = 0;
218 	if ((error = bus_dmamap_load(sc->sc_cdmatag, sc->sc_cddmamap,
219 	    sc->sc_control_data, sizeof(struct gem_control_data),
220 	    gem_cddma_callback, sc, 0)) != 0 || sc->sc_cddma == 0) {
221 		device_printf(sc->sc_dev,
222 		    "unable to load control data DMA map, error = %d\n",
223 		    error);
224 		goto fail_cmem;
225 	}
226 
227 	/*
228 	 * Initialize the transmit job descriptors.
229 	 */
230 	STAILQ_INIT(&sc->sc_txfreeq);
231 	STAILQ_INIT(&sc->sc_txdirtyq);
232 
233 	/*
234 	 * Create the transmit buffer DMA maps.
235 	 */
236 	error = ENOMEM;
237 	for (i = 0; i < GEM_TXQUEUELEN; i++) {
238 		txs = &sc->sc_txsoft[i];
239 		txs->txs_mbuf = NULL;
240 		txs->txs_ndescs = 0;
241 		if ((error = bus_dmamap_create(sc->sc_tdmatag, 0,
242 		    &txs->txs_dmamap)) != 0) {
243 			device_printf(sc->sc_dev,
244 			    "unable to create TX DMA map %d, error = %d\n",
245 			    i, error);
246 			goto fail_txd;
247 		}
248 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
249 	}
250 
251 	/*
252 	 * Create the receive buffer DMA maps.
253 	 */
254 	for (i = 0; i < GEM_NRXDESC; i++) {
255 		if ((error = bus_dmamap_create(sc->sc_rdmatag, 0,
256 		    &sc->sc_rxsoft[i].rxs_dmamap)) != 0) {
257 			device_printf(sc->sc_dev,
258 			    "unable to create RX DMA map %d, error = %d\n",
259 			    i, error);
260 			goto fail_rxd;
261 		}
262 		sc->sc_rxsoft[i].rxs_mbuf = NULL;
263 	}
264 
265 	/* Bypass probing PHYs if we already know for sure to use a SERDES. */
266 	if ((sc->sc_flags & GEM_SERDES) != 0)
267 		goto serdes;
268 
269 	GEM_WRITE_4(sc, GEM_MII_DATAPATH_MODE, GEM_MII_DATAPATH_MII);
270 	GEM_BARRIER(sc, GEM_MII_DATAPATH_MODE, 4,
271 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
272 
273 	gem_mifinit(sc);
274 
275 	/*
276 	 * Look for an external PHY.
277 	 */
278 	error = ENXIO;
279 	v = GEM_READ_4(sc, GEM_MIF_CONFIG);
280 	if ((v & GEM_MIF_CONFIG_MDI1) != 0) {
281 		v |= GEM_MIF_CONFIG_PHY_SEL;
282 		GEM_WRITE_4(sc, GEM_MIF_CONFIG, v);
283 		GEM_BARRIER(sc, GEM_MIF_CONFIG, 4,
284 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
285 		error = mii_attach(sc->sc_dev, &sc->sc_miibus, ifp,
286 		    gem_mediachange, gem_mediastatus, BMSR_DEFCAPMASK,
287 		    MII_PHY_ANY, MII_OFFSET_ANY, MIIF_DOPAUSE);
288 	}
289 
290 	/*
291 	 * Fall back on an internal PHY if no external PHY was found.
292 	 * Note that with Apple (K2) GMACs GEM_MIF_CONFIG_MDI0 can't be
293 	 * trusted when the firmware has powered down the chip.
294 	 */
295 	if (error != 0 &&
296 	    ((v & GEM_MIF_CONFIG_MDI0) != 0 || GEM_IS_APPLE(sc))) {
297 		v &= ~GEM_MIF_CONFIG_PHY_SEL;
298 		GEM_WRITE_4(sc, GEM_MIF_CONFIG, v);
299 		GEM_BARRIER(sc, GEM_MIF_CONFIG, 4,
300 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
301 		switch (sc->sc_variant) {
302 		case GEM_APPLE_K2_GMAC:
303 			phy = GEM_PHYAD_INTERNAL;
304 			break;
305 		case GEM_APPLE_GMAC:
306 			phy = GEM_PHYAD_EXTERNAL;
307 			break;
308 		default:
309 			phy = MII_PHY_ANY;
310 			break;
311 		}
312 		error = mii_attach(sc->sc_dev, &sc->sc_miibus, ifp,
313 		    gem_mediachange, gem_mediastatus, BMSR_DEFCAPMASK, phy,
314 		    MII_OFFSET_ANY, MIIF_DOPAUSE);
315 	}
316 
317 	/*
318 	 * Try the external PCS SERDES if we didn't find any PHYs.
319 	 */
320 	if (error != 0 && sc->sc_variant == GEM_SUN_GEM) {
321  serdes:
322 		GEM_WRITE_4(sc, GEM_MII_DATAPATH_MODE,
323 		    GEM_MII_DATAPATH_SERDES);
324 		GEM_BARRIER(sc, GEM_MII_DATAPATH_MODE, 4,
325 		    BUS_SPACE_BARRIER_WRITE);
326 		GEM_WRITE_4(sc, GEM_MII_SLINK_CONTROL,
327 		    GEM_MII_SLINK_LOOPBACK | GEM_MII_SLINK_EN_SYNC_D);
328 		GEM_BARRIER(sc, GEM_MII_SLINK_CONTROL, 4,
329 		    BUS_SPACE_BARRIER_WRITE);
330 		GEM_WRITE_4(sc, GEM_MII_CONFIG, GEM_MII_CONFIG_ENABLE);
331 		GEM_BARRIER(sc, GEM_MII_CONFIG, 4,
332 		    BUS_SPACE_BARRIER_WRITE);
333 		sc->sc_flags |= GEM_SERDES;
334 		error = mii_attach(sc->sc_dev, &sc->sc_miibus, ifp,
335 		    gem_mediachange, gem_mediastatus, BMSR_DEFCAPMASK,
336 		    GEM_PHYAD_EXTERNAL, MII_OFFSET_ANY, MIIF_DOPAUSE);
337 	}
338 	if (error != 0) {
339 		device_printf(sc->sc_dev, "attaching PHYs failed\n");
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_READ_4(sc, GEM_RX_FIFO_SIZE);
353 
354 	/* Get TX FIFO size. */
355 	v = GEM_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 	if_setifheaderlen(ifp, sizeof(struct ether_vlan_header));
366 	if_setcapabilitiesbit(ifp, IFCAP_VLAN_MTU | IFCAP_HWCSUM, 0);
367 	if_sethwassistbits(ifp, sc->sc_csum_features, 0);
368 	if_setcapenablebit(ifp, IFCAP_VLAN_MTU | IFCAP_HWCSUM, 0);
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 	if_t 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 	if_t 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 	if_t 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 (if_getflags(ifp) & 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 	if_t 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 	if_inc_counter(ifp, IFCOUNTER_COLLISIONS,
552 	    GEM_READ_4(sc, GEM_MAC_NORM_COLL_CNT) +
553 	    GEM_READ_4(sc, GEM_MAC_FIRST_COLL_CNT));
554 	v = GEM_READ_4(sc, GEM_MAC_EXCESS_COLL_CNT) +
555 	    GEM_READ_4(sc, GEM_MAC_LATE_COLL_CNT);
556 	if_inc_counter(ifp, IFCOUNTER_COLLISIONS, v);
557 	if_inc_counter(ifp, IFCOUNTER_OERRORS, v);
558 	if_inc_counter(ifp, IFCOUNTER_IERRORS,
559 	    GEM_READ_4(sc, GEM_MAC_RX_LEN_ERR_CNT) +
560 	    GEM_READ_4(sc, GEM_MAC_RX_ALIGN_ERR) +
561 	    GEM_READ_4(sc, GEM_MAC_RX_CRC_ERR_CNT) +
562 	    GEM_READ_4(sc, GEM_MAC_RX_CODE_VIOL));
563 
564 	/*
565 	 * Then clear the hardware counters.
566 	 */
567 	GEM_WRITE_4(sc, GEM_MAC_NORM_COLL_CNT, 0);
568 	GEM_WRITE_4(sc, GEM_MAC_FIRST_COLL_CNT, 0);
569 	GEM_WRITE_4(sc, GEM_MAC_EXCESS_COLL_CNT, 0);
570 	GEM_WRITE_4(sc, GEM_MAC_LATE_COLL_CNT, 0);
571 	GEM_WRITE_4(sc, GEM_MAC_RX_LEN_ERR_CNT, 0);
572 	GEM_WRITE_4(sc, GEM_MAC_RX_ALIGN_ERR, 0);
573 	GEM_WRITE_4(sc, GEM_MAC_RX_CRC_ERR_CNT, 0);
574 	GEM_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, bus_addr_t r, uint32_t clr, uint32_t set)
586 {
587 	int i;
588 	uint32_t reg;
589 
590 	for (i = GEM_TRIES; i--; DELAY(100)) {
591 		reg = GEM_READ_4(sc, r);
592 		if ((reg & clr) == 0 && (reg & set) == set)
593 			return (1);
594 	}
595 	return (0);
596 }
597 
598 static void
599 gem_reset(struct gem_softc *sc)
600 {
601 
602 #ifdef GEM_DEBUG
603 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
604 #endif
605 	gem_reset_rx(sc);
606 	gem_reset_tx(sc);
607 
608 	/* Do a full reset. */
609 	GEM_WRITE_4(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX);
610 	GEM_BARRIER(sc, GEM_RESET, 4,
611 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
612 	if (!gem_bitwait(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX, 0))
613 		device_printf(sc->sc_dev, "cannot reset device\n");
614 }
615 
616 static void
617 gem_rxdrain(struct gem_softc *sc)
618 {
619 	struct gem_rxsoft *rxs;
620 	int i;
621 
622 	for (i = 0; i < GEM_NRXDESC; i++) {
623 		rxs = &sc->sc_rxsoft[i];
624 		if (rxs->rxs_mbuf != NULL) {
625 			bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
626 			    BUS_DMASYNC_POSTREAD);
627 			bus_dmamap_unload(sc->sc_rdmatag, rxs->rxs_dmamap);
628 			m_freem(rxs->rxs_mbuf);
629 			rxs->rxs_mbuf = NULL;
630 		}
631 	}
632 }
633 
634 static void
635 gem_stop(if_t ifp, int disable)
636 {
637 	struct gem_softc *sc = if_getsoftc(ifp);
638 	struct gem_txsoft *txs;
639 
640 #ifdef GEM_DEBUG
641 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
642 #endif
643 
644 	callout_stop(&sc->sc_tick_ch);
645 #ifdef GEM_RINT_TIMEOUT
646 	callout_stop(&sc->sc_rx_ch);
647 #endif
648 
649 	gem_reset_tx(sc);
650 	gem_reset_rx(sc);
651 
652 	/*
653 	 * Release any queued transmit buffers.
654 	 */
655 	while ((txs = STAILQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
656 		STAILQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
657 		if (txs->txs_ndescs != 0) {
658 			bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
659 			    BUS_DMASYNC_POSTWRITE);
660 			bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
661 			if (txs->txs_mbuf != NULL) {
662 				m_freem(txs->txs_mbuf);
663 				txs->txs_mbuf = NULL;
664 			}
665 		}
666 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
667 	}
668 
669 	if (disable)
670 		gem_rxdrain(sc);
671 
672 	/*
673 	 * Mark the interface down and cancel the watchdog timer.
674 	 */
675 	if_setdrvflagbits(ifp, 0, (IFF_DRV_RUNNING | IFF_DRV_OACTIVE));
676 	sc->sc_flags &= ~GEM_LINK;
677 	sc->sc_wdog_timer = 0;
678 }
679 
680 static int
681 gem_reset_rx(struct gem_softc *sc)
682 {
683 
684 	/*
685 	 * Resetting while DMA is in progress can cause a bus hang, so we
686 	 * disable DMA first.
687 	 */
688 	(void)gem_disable_rx(sc);
689 	GEM_WRITE_4(sc, GEM_RX_CONFIG, 0);
690 	GEM_BARRIER(sc, GEM_RX_CONFIG, 4,
691 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
692 	if (!gem_bitwait(sc, GEM_RX_CONFIG, GEM_RX_CONFIG_RXDMA_EN, 0))
693 		device_printf(sc->sc_dev, "cannot disable RX DMA\n");
694 
695 	/* Wait 5ms extra. */
696 	DELAY(5000);
697 
698 	/* Reset the ERX. */
699 	GEM_WRITE_4(sc, GEM_RESET, GEM_RESET_RX);
700 	GEM_BARRIER(sc, GEM_RESET, 4,
701 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
702 	if (!gem_bitwait(sc, GEM_RESET, GEM_RESET_RX, 0)) {
703 		device_printf(sc->sc_dev, "cannot reset receiver\n");
704 		return (1);
705 	}
706 
707 	/* Finally, reset RX MAC. */
708 	GEM_WRITE_4(sc, GEM_MAC_RXRESET, 1);
709 	GEM_BARRIER(sc, GEM_MAC_RXRESET, 4,
710 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
711 	if (!gem_bitwait(sc, GEM_MAC_RXRESET, 1, 0)) {
712 		device_printf(sc->sc_dev, "cannot reset RX MAC\n");
713 		return (1);
714 	}
715 
716 	return (0);
717 }
718 
719 /*
720  * Reset the receiver DMA engine.
721  *
722  * Intended to be used in case of GEM_INTR_RX_TAG_ERR, GEM_MAC_RX_OVERFLOW
723  * etc in order to reset the receiver DMA engine only and not do a full
724  * reset which amongst others also downs the link and clears the FIFOs.
725  */
726 static void
727 gem_reset_rxdma(struct gem_softc *sc)
728 {
729 	int i;
730 
731 	if (gem_reset_rx(sc) != 0) {
732 		if_setdrvflagbits(sc->sc_ifp, 0, IFF_DRV_RUNNING);
733 		return (gem_init_locked(sc));
734 	}
735 	for (i = 0; i < GEM_NRXDESC; i++)
736 		if (sc->sc_rxsoft[i].rxs_mbuf != NULL)
737 			GEM_UPDATE_RXDESC(sc, i);
738 	sc->sc_rxptr = 0;
739 	GEM_CDSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
740 
741 	/* NOTE: we use only 32-bit DMA addresses here. */
742 	GEM_WRITE_4(sc, GEM_RX_RING_PTR_HI, 0);
743 	GEM_WRITE_4(sc, GEM_RX_RING_PTR_LO, GEM_CDRXADDR(sc, 0));
744 	GEM_WRITE_4(sc, GEM_RX_KICK, GEM_NRXDESC - 4);
745 	GEM_WRITE_4(sc, GEM_RX_CONFIG,
746 	    gem_ringsize(GEM_NRXDESC /* XXX */) |
747 	    ((ETHER_HDR_LEN + sizeof(struct ip)) <<
748 	    GEM_RX_CONFIG_CXM_START_SHFT) |
749 	    (GEM_THRSH_1024 << GEM_RX_CONFIG_FIFO_THRS_SHIFT) |
750 	    (ETHER_ALIGN << GEM_RX_CONFIG_FBOFF_SHFT));
751 	GEM_WRITE_4(sc, GEM_RX_BLANKING,
752 	    ((6 * (sc->sc_flags & GEM_PCI66) != 0 ? 2 : 1) <<
753 	    GEM_RX_BLANKING_TIME_SHIFT) | 6);
754 	GEM_WRITE_4(sc, GEM_RX_PAUSE_THRESH,
755 	    (3 * sc->sc_rxfifosize / 256) |
756 	    ((sc->sc_rxfifosize / 256) << 12));
757 	GEM_WRITE_4(sc, GEM_RX_CONFIG,
758 	    GEM_READ_4(sc, GEM_RX_CONFIG) | GEM_RX_CONFIG_RXDMA_EN);
759 	GEM_WRITE_4(sc, GEM_MAC_RX_MASK,
760 	    GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT);
761 	/*
762 	 * Clear the RX filter and reprogram it.  This will also set the
763 	 * current RX MAC configuration and enable it.
764 	 */
765 	gem_setladrf(sc);
766 }
767 
768 static int
769 gem_reset_tx(struct gem_softc *sc)
770 {
771 
772 	/*
773 	 * Resetting while DMA is in progress can cause a bus hang, so we
774 	 * disable DMA first.
775 	 */
776 	(void)gem_disable_tx(sc);
777 	GEM_WRITE_4(sc, GEM_TX_CONFIG, 0);
778 	GEM_BARRIER(sc, GEM_TX_CONFIG, 4,
779 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
780 	if (!gem_bitwait(sc, GEM_TX_CONFIG, GEM_TX_CONFIG_TXDMA_EN, 0))
781 		device_printf(sc->sc_dev, "cannot disable TX DMA\n");
782 
783 	/* Wait 5ms extra. */
784 	DELAY(5000);
785 
786 	/* Finally, reset the ETX. */
787 	GEM_WRITE_4(sc, GEM_RESET, GEM_RESET_TX);
788 	GEM_BARRIER(sc, GEM_RESET, 4,
789 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
790 	if (!gem_bitwait(sc, GEM_RESET, GEM_RESET_TX, 0)) {
791 		device_printf(sc->sc_dev, "cannot reset transmitter\n");
792 		return (1);
793 	}
794 	return (0);
795 }
796 
797 static int
798 gem_disable_rx(struct gem_softc *sc)
799 {
800 
801 	GEM_WRITE_4(sc, GEM_MAC_RX_CONFIG,
802 	    GEM_READ_4(sc, GEM_MAC_RX_CONFIG) & ~GEM_MAC_RX_ENABLE);
803 	GEM_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
804 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
805 	if (gem_bitwait(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_ENABLE, 0))
806 		return (1);
807 	device_printf(sc->sc_dev, "cannot disable RX MAC\n");
808 	return (0);
809 }
810 
811 static int
812 gem_disable_tx(struct gem_softc *sc)
813 {
814 
815 	GEM_WRITE_4(sc, GEM_MAC_TX_CONFIG,
816 	    GEM_READ_4(sc, GEM_MAC_TX_CONFIG) & ~GEM_MAC_TX_ENABLE);
817 	GEM_BARRIER(sc, GEM_MAC_TX_CONFIG, 4,
818 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
819 	if (gem_bitwait(sc, GEM_MAC_TX_CONFIG, GEM_MAC_TX_ENABLE, 0))
820 		return (1);
821 	device_printf(sc->sc_dev, "cannot disable TX MAC\n");
822 	return (0);
823 }
824 
825 static int
826 gem_meminit(struct gem_softc *sc)
827 {
828 	struct gem_rxsoft *rxs;
829 	int error, i;
830 
831 	GEM_LOCK_ASSERT(sc, MA_OWNED);
832 
833 	/*
834 	 * Initialize the transmit descriptor ring.
835 	 */
836 	for (i = 0; i < GEM_NTXDESC; i++) {
837 		sc->sc_txdescs[i].gd_flags = 0;
838 		sc->sc_txdescs[i].gd_addr = 0;
839 	}
840 	sc->sc_txfree = GEM_MAXTXFREE;
841 	sc->sc_txnext = 0;
842 	sc->sc_txwin = 0;
843 
844 	/*
845 	 * Initialize the receive descriptor and receive job
846 	 * descriptor rings.
847 	 */
848 	for (i = 0; i < GEM_NRXDESC; i++) {
849 		rxs = &sc->sc_rxsoft[i];
850 		if (rxs->rxs_mbuf == NULL) {
851 			if ((error = gem_add_rxbuf(sc, i)) != 0) {
852 				device_printf(sc->sc_dev,
853 				    "unable to allocate or map RX buffer %d, "
854 				    "error = %d\n", i, error);
855 				/*
856 				 * XXX we should attempt to run with fewer
857 				 * receive buffers instead of just failing.
858 				 */
859 				gem_rxdrain(sc);
860 				return (1);
861 			}
862 		} else
863 			GEM_INIT_RXDESC(sc, i);
864 	}
865 	sc->sc_rxptr = 0;
866 
867 	GEM_CDSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
868 
869 	return (0);
870 }
871 
872 static u_int
873 gem_ringsize(u_int sz)
874 {
875 
876 	switch (sz) {
877 	case 32:
878 		return (GEM_RING_SZ_32);
879 	case 64:
880 		return (GEM_RING_SZ_64);
881 	case 128:
882 		return (GEM_RING_SZ_128);
883 	case 256:
884 		return (GEM_RING_SZ_256);
885 	case 512:
886 		return (GEM_RING_SZ_512);
887 	case 1024:
888 		return (GEM_RING_SZ_1024);
889 	case 2048:
890 		return (GEM_RING_SZ_2048);
891 	case 4096:
892 		return (GEM_RING_SZ_4096);
893 	case 8192:
894 		return (GEM_RING_SZ_8192);
895 	default:
896 		printf("%s: invalid ring size %d\n", __func__, sz);
897 		return (GEM_RING_SZ_32);
898 	}
899 }
900 
901 static void
902 gem_init(void *xsc)
903 {
904 	struct gem_softc *sc = xsc;
905 
906 	GEM_LOCK(sc);
907 	gem_init_locked(sc);
908 	GEM_UNLOCK(sc);
909 }
910 
911 /*
912  * Initialization of interface; set up initialization block
913  * and transmit/receive descriptor rings.
914  */
915 static void
916 gem_init_locked(struct gem_softc *sc)
917 {
918 	if_t ifp = sc->sc_ifp;
919 	uint32_t v;
920 
921 	GEM_LOCK_ASSERT(sc, MA_OWNED);
922 
923 	if ((if_getdrvflags(ifp) & IFF_DRV_RUNNING) != 0)
924 		return;
925 
926 #ifdef GEM_DEBUG
927 	CTR2(KTR_GEM, "%s: %s: calling stop", device_get_name(sc->sc_dev),
928 	    __func__);
929 #endif
930 	/*
931 	 * Initialization sequence.  The numbered steps below correspond
932 	 * to the sequence outlined in section 6.3.5.1 in the Ethernet
933 	 * Channel Engine manual (part of the PCIO manual).
934 	 * See also the STP2002-STQ document from Sun Microsystems.
935 	 */
936 
937 	/* step 1 & 2.  Reset the Ethernet Channel. */
938 	gem_stop(ifp, 0);
939 	gem_reset(sc);
940 #ifdef GEM_DEBUG
941 	CTR2(KTR_GEM, "%s: %s: restarting", device_get_name(sc->sc_dev),
942 	    __func__);
943 #endif
944 
945 	if ((sc->sc_flags & GEM_SERDES) == 0)
946 		/* Re-initialize the MIF. */
947 		gem_mifinit(sc);
948 
949 	/* step 3.  Setup data structures in host memory. */
950 	if (gem_meminit(sc) != 0)
951 		return;
952 
953 	/* step 4.  TX MAC registers & counters */
954 	gem_init_regs(sc);
955 
956 	/* step 5.  RX MAC registers & counters */
957 
958 	/* step 6 & 7.  Program Descriptor Ring Base Addresses. */
959 	/* NOTE: we use only 32-bit DMA addresses here. */
960 	GEM_WRITE_4(sc, GEM_TX_RING_PTR_HI, 0);
961 	GEM_WRITE_4(sc, GEM_TX_RING_PTR_LO, GEM_CDTXADDR(sc, 0));
962 
963 	GEM_WRITE_4(sc, GEM_RX_RING_PTR_HI, 0);
964 	GEM_WRITE_4(sc, GEM_RX_RING_PTR_LO, GEM_CDRXADDR(sc, 0));
965 #ifdef GEM_DEBUG
966 	CTR3(KTR_GEM, "loading RX ring %lx, TX ring %lx, cddma %lx",
967 	    GEM_CDRXADDR(sc, 0), GEM_CDTXADDR(sc, 0), sc->sc_cddma);
968 #endif
969 
970 	/* step 8.  Global Configuration & Interrupt Mask */
971 
972 	/*
973 	 * Set the internal arbitration to "infinite" bursts of the
974 	 * maximum length of 31 * 64 bytes so DMA transfers aren't
975 	 * split up in cache line size chunks.  This greatly improves
976 	 * RX performance.
977 	 * Enable silicon bug workarounds for the Apple variants.
978 	 */
979 	GEM_WRITE_4(sc, GEM_CONFIG,
980 	    GEM_CONFIG_TXDMA_LIMIT | GEM_CONFIG_RXDMA_LIMIT |
981 	    GEM_CONFIG_BURST_INF | (GEM_IS_APPLE(sc) ?
982 	    GEM_CONFIG_RONPAULBIT | GEM_CONFIG_BUG2FIX : 0));
983 
984 	GEM_WRITE_4(sc, GEM_INTMASK,
985 	    ~(GEM_INTR_TX_INTME | GEM_INTR_TX_EMPTY | GEM_INTR_RX_DONE |
986 	    GEM_INTR_RX_NOBUF | GEM_INTR_RX_TAG_ERR | GEM_INTR_PERR |
987 	    GEM_INTR_BERR
988 #ifdef GEM_DEBUG
989 	    | GEM_INTR_PCS | GEM_INTR_MIF
990 #endif
991 	    ));
992 	GEM_WRITE_4(sc, GEM_MAC_RX_MASK,
993 	    GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT);
994 	GEM_WRITE_4(sc, GEM_MAC_TX_MASK,
995 	    GEM_MAC_TX_XMIT_DONE | GEM_MAC_TX_DEFER_EXP |
996 	    GEM_MAC_TX_PEAK_EXP);
997 #ifdef GEM_DEBUG
998 	GEM_WRITE_4(sc, GEM_MAC_CONTROL_MASK,
999 	    ~(GEM_MAC_PAUSED | GEM_MAC_PAUSE | GEM_MAC_RESUME));
1000 #else
1001 	GEM_WRITE_4(sc, GEM_MAC_CONTROL_MASK,
1002 	    GEM_MAC_PAUSED | GEM_MAC_PAUSE | GEM_MAC_RESUME);
1003 #endif
1004 
1005 	/* step 9.  ETX Configuration: use mostly default values. */
1006 
1007 	/* Enable DMA. */
1008 	v = gem_ringsize(GEM_NTXDESC);
1009 	/* Set TX FIFO threshold and enable DMA. */
1010 	v |= (0x4ff << 10) & GEM_TX_CONFIG_TXFIFO_TH;
1011 	GEM_WRITE_4(sc, GEM_TX_CONFIG, v | GEM_TX_CONFIG_TXDMA_EN);
1012 
1013 	/* step 10.  ERX Configuration */
1014 
1015 	/* Encode Receive Descriptor ring size. */
1016 	v = gem_ringsize(GEM_NRXDESC /* XXX */);
1017 	/* RX TCP/UDP checksum offset */
1018 	v |= ((ETHER_HDR_LEN + sizeof(struct ip)) <<
1019 	    GEM_RX_CONFIG_CXM_START_SHFT);
1020 	/* Set RX FIFO threshold, set first byte offset and enable DMA. */
1021 	GEM_WRITE_4(sc, GEM_RX_CONFIG,
1022 	    v | (GEM_THRSH_1024 << GEM_RX_CONFIG_FIFO_THRS_SHIFT) |
1023 	    (ETHER_ALIGN << GEM_RX_CONFIG_FBOFF_SHFT) |
1024 	    GEM_RX_CONFIG_RXDMA_EN);
1025 
1026 	GEM_WRITE_4(sc, GEM_RX_BLANKING,
1027 	    ((6 * (sc->sc_flags & GEM_PCI66) != 0 ? 2 : 1) <<
1028 	    GEM_RX_BLANKING_TIME_SHIFT) | 6);
1029 
1030 	/*
1031 	 * The following value is for an OFF Threshold of about 3/4 full
1032 	 * and an ON Threshold of 1/4 full.
1033 	 */
1034 	GEM_WRITE_4(sc, GEM_RX_PAUSE_THRESH,
1035 	    (3 * sc->sc_rxfifosize / 256) |
1036 	    ((sc->sc_rxfifosize / 256) << 12));
1037 
1038 	/* step 11.  Configure Media. */
1039 
1040 	/* step 12.  RX_MAC Configuration Register */
1041 	v = GEM_READ_4(sc, GEM_MAC_RX_CONFIG);
1042 	v &= ~GEM_MAC_RX_ENABLE;
1043 	v |= GEM_MAC_RX_STRIP_CRC;
1044 	sc->sc_mac_rxcfg = v;
1045 	/*
1046 	 * Clear the RX filter and reprogram it.  This will also set the
1047 	 * current RX MAC configuration and enable it.
1048 	 */
1049 	gem_setladrf(sc);
1050 
1051 	/* step 13.  TX_MAC Configuration Register */
1052 	v = GEM_READ_4(sc, GEM_MAC_TX_CONFIG);
1053 	v |= GEM_MAC_TX_ENABLE;
1054 	(void)gem_disable_tx(sc);
1055 	GEM_WRITE_4(sc, GEM_MAC_TX_CONFIG, v);
1056 
1057 	/* step 14.  Issue Transmit Pending command. */
1058 
1059 	/* step 15.  Give the receiver a swift kick. */
1060 	GEM_WRITE_4(sc, GEM_RX_KICK, GEM_NRXDESC - 4);
1061 
1062 	if_setdrvflagbits(ifp, IFF_DRV_RUNNING, 0);
1063 	if_setdrvflagbits(ifp, 0, IFF_DRV_OACTIVE);
1064 
1065 	mii_mediachg(sc->sc_mii);
1066 
1067 	/* Start the one second timer. */
1068 	sc->sc_wdog_timer = 0;
1069 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
1070 }
1071 
1072 static int
1073 gem_load_txmbuf(struct gem_softc *sc, struct mbuf **m_head)
1074 {
1075 	bus_dma_segment_t txsegs[GEM_NTXSEGS];
1076 	struct gem_txsoft *txs;
1077 	struct ip *ip;
1078 	struct mbuf *m;
1079 	uint64_t cflags, flags;
1080 	int error, nexttx, nsegs, offset, seg;
1081 
1082 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1083 
1084 	/* Get a work queue entry. */
1085 	if ((txs = STAILQ_FIRST(&sc->sc_txfreeq)) == NULL) {
1086 		/* Ran out of descriptors. */
1087 		return (ENOBUFS);
1088 	}
1089 
1090 	cflags = 0;
1091 	if (((*m_head)->m_pkthdr.csum_flags & sc->sc_csum_features) != 0) {
1092 		if (M_WRITABLE(*m_head) == 0) {
1093 			m = m_dup(*m_head, M_NOWAIT);
1094 			m_freem(*m_head);
1095 			*m_head = m;
1096 			if (m == NULL)
1097 				return (ENOBUFS);
1098 		}
1099 		offset = sizeof(struct ether_header);
1100 		m = m_pullup(*m_head, offset + sizeof(struct ip));
1101 		if (m == NULL) {
1102 			*m_head = NULL;
1103 			return (ENOBUFS);
1104 		}
1105 		ip = (struct ip *)(mtod(m, caddr_t) + offset);
1106 		offset += (ip->ip_hl << 2);
1107 		cflags = offset << GEM_TD_CXSUM_STARTSHFT |
1108 		    ((offset + m->m_pkthdr.csum_data) <<
1109 		    GEM_TD_CXSUM_STUFFSHFT) | GEM_TD_CXSUM_ENABLE;
1110 		*m_head = m;
1111 	}
1112 
1113 	error = bus_dmamap_load_mbuf_sg(sc->sc_tdmatag, txs->txs_dmamap,
1114 	    *m_head, txsegs, &nsegs, BUS_DMA_NOWAIT);
1115 	if (error == EFBIG) {
1116 		m = m_collapse(*m_head, M_NOWAIT, GEM_NTXSEGS);
1117 		if (m == NULL) {
1118 			m_freem(*m_head);
1119 			*m_head = NULL;
1120 			return (ENOBUFS);
1121 		}
1122 		*m_head = m;
1123 		error = bus_dmamap_load_mbuf_sg(sc->sc_tdmatag,
1124 		    txs->txs_dmamap, *m_head, txsegs, &nsegs,
1125 		    BUS_DMA_NOWAIT);
1126 		if (error != 0) {
1127 			m_freem(*m_head);
1128 			*m_head = NULL;
1129 			return (error);
1130 		}
1131 	} else if (error != 0)
1132 		return (error);
1133 	/* If nsegs is wrong then the stack is corrupt. */
1134 	KASSERT(nsegs <= GEM_NTXSEGS,
1135 	    ("%s: too many DMA segments (%d)", __func__, nsegs));
1136 	if (nsegs == 0) {
1137 		m_freem(*m_head);
1138 		*m_head = NULL;
1139 		return (EIO);
1140 	}
1141 
1142 	/*
1143 	 * Ensure we have enough descriptors free to describe
1144 	 * the packet.  Note, we always reserve one descriptor
1145 	 * at the end of the ring as a termination point, in
1146 	 * order to prevent wrap-around.
1147 	 */
1148 	if (nsegs > sc->sc_txfree - 1) {
1149 		txs->txs_ndescs = 0;
1150 		bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
1151 		return (ENOBUFS);
1152 	}
1153 
1154 	txs->txs_ndescs = nsegs;
1155 	txs->txs_firstdesc = sc->sc_txnext;
1156 	nexttx = txs->txs_firstdesc;
1157 	for (seg = 0; seg < nsegs; seg++, nexttx = GEM_NEXTTX(nexttx)) {
1158 #ifdef GEM_DEBUG
1159 		CTR6(KTR_GEM,
1160 		    "%s: mapping seg %d (txd %d), len %lx, addr %#lx (%#lx)",
1161 		    __func__, seg, nexttx, txsegs[seg].ds_len,
1162 		    txsegs[seg].ds_addr, htole64(txsegs[seg].ds_addr));
1163 #endif
1164 		sc->sc_txdescs[nexttx].gd_addr = htole64(txsegs[seg].ds_addr);
1165 		KASSERT(txsegs[seg].ds_len < GEM_TD_BUFSIZE,
1166 		    ("%s: segment size too large!", __func__));
1167 		flags = txsegs[seg].ds_len & GEM_TD_BUFSIZE;
1168 		sc->sc_txdescs[nexttx].gd_flags = htole64(flags | cflags);
1169 		txs->txs_lastdesc = nexttx;
1170 	}
1171 
1172 	/* Set EOP on the last descriptor. */
1173 #ifdef GEM_DEBUG
1174 	CTR3(KTR_GEM, "%s: end of packet at segment %d, TX %d",
1175 	    __func__, seg, nexttx);
1176 #endif
1177 	sc->sc_txdescs[txs->txs_lastdesc].gd_flags |=
1178 	    htole64(GEM_TD_END_OF_PACKET);
1179 
1180 	/* Lastly set SOP on the first descriptor. */
1181 #ifdef GEM_DEBUG
1182 	CTR3(KTR_GEM, "%s: start of packet at segment %d, TX %d",
1183 	    __func__, seg, nexttx);
1184 #endif
1185 	if (++sc->sc_txwin > GEM_NTXSEGS * 2 / 3) {
1186 		sc->sc_txwin = 0;
1187 		sc->sc_txdescs[txs->txs_firstdesc].gd_flags |=
1188 		    htole64(GEM_TD_INTERRUPT_ME | GEM_TD_START_OF_PACKET);
1189 	} else
1190 		sc->sc_txdescs[txs->txs_firstdesc].gd_flags |=
1191 		    htole64(GEM_TD_START_OF_PACKET);
1192 
1193 	/* Sync the DMA map. */
1194 	bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
1195 	    BUS_DMASYNC_PREWRITE);
1196 
1197 #ifdef GEM_DEBUG
1198 	CTR4(KTR_GEM, "%s: setting firstdesc=%d, lastdesc=%d, ndescs=%d",
1199 	    __func__, txs->txs_firstdesc, txs->txs_lastdesc,
1200 	    txs->txs_ndescs);
1201 #endif
1202 	STAILQ_REMOVE_HEAD(&sc->sc_txfreeq, txs_q);
1203 	STAILQ_INSERT_TAIL(&sc->sc_txdirtyq, txs, txs_q);
1204 	txs->txs_mbuf = *m_head;
1205 
1206 	sc->sc_txnext = GEM_NEXTTX(txs->txs_lastdesc);
1207 	sc->sc_txfree -= txs->txs_ndescs;
1208 
1209 	return (0);
1210 }
1211 
1212 static void
1213 gem_init_regs(struct gem_softc *sc)
1214 {
1215 	const u_char *laddr = if_getlladdr(sc->sc_ifp);
1216 
1217 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1218 
1219 	/* These registers are not cleared on reset. */
1220 	if ((sc->sc_flags & GEM_INITED) == 0) {
1221 		/* magic values */
1222 		GEM_WRITE_4(sc, GEM_MAC_IPG0, 0);
1223 		GEM_WRITE_4(sc, GEM_MAC_IPG1, 8);
1224 		GEM_WRITE_4(sc, GEM_MAC_IPG2, 4);
1225 
1226 		/* min frame length */
1227 		GEM_WRITE_4(sc, GEM_MAC_MAC_MIN_FRAME, ETHER_MIN_LEN);
1228 		/* max frame length and max burst size */
1229 		GEM_WRITE_4(sc, GEM_MAC_MAC_MAX_FRAME,
1230 		    (ETHER_MAX_LEN + ETHER_VLAN_ENCAP_LEN) | (0x2000 << 16));
1231 
1232 		/* more magic values */
1233 		GEM_WRITE_4(sc, GEM_MAC_PREAMBLE_LEN, 0x7);
1234 		GEM_WRITE_4(sc, GEM_MAC_JAM_SIZE, 0x4);
1235 		GEM_WRITE_4(sc, GEM_MAC_ATTEMPT_LIMIT, 0x10);
1236 		GEM_WRITE_4(sc, GEM_MAC_CONTROL_TYPE, 0x8808);
1237 
1238 		/* random number seed */
1239 		GEM_WRITE_4(sc, GEM_MAC_RANDOM_SEED,
1240 		    ((laddr[5] << 8) | laddr[4]) & 0x3ff);
1241 
1242 		/* secondary MAC address: 0:0:0:0:0:0 */
1243 		GEM_WRITE_4(sc, GEM_MAC_ADDR3, 0);
1244 		GEM_WRITE_4(sc, GEM_MAC_ADDR4, 0);
1245 		GEM_WRITE_4(sc, GEM_MAC_ADDR5, 0);
1246 
1247 		/* MAC control address: 01:80:c2:00:00:01 */
1248 		GEM_WRITE_4(sc, GEM_MAC_ADDR6, 0x0001);
1249 		GEM_WRITE_4(sc, GEM_MAC_ADDR7, 0xc200);
1250 		GEM_WRITE_4(sc, GEM_MAC_ADDR8, 0x0180);
1251 
1252 		/* MAC filter address: 0:0:0:0:0:0 */
1253 		GEM_WRITE_4(sc, GEM_MAC_ADDR_FILTER0, 0);
1254 		GEM_WRITE_4(sc, GEM_MAC_ADDR_FILTER1, 0);
1255 		GEM_WRITE_4(sc, GEM_MAC_ADDR_FILTER2, 0);
1256 		GEM_WRITE_4(sc, GEM_MAC_ADR_FLT_MASK1_2, 0);
1257 		GEM_WRITE_4(sc, GEM_MAC_ADR_FLT_MASK0, 0);
1258 
1259 		sc->sc_flags |= GEM_INITED;
1260 	}
1261 
1262 	/* Counters need to be zeroed. */
1263 	GEM_WRITE_4(sc, GEM_MAC_NORM_COLL_CNT, 0);
1264 	GEM_WRITE_4(sc, GEM_MAC_FIRST_COLL_CNT, 0);
1265 	GEM_WRITE_4(sc, GEM_MAC_EXCESS_COLL_CNT, 0);
1266 	GEM_WRITE_4(sc, GEM_MAC_LATE_COLL_CNT, 0);
1267 	GEM_WRITE_4(sc, GEM_MAC_DEFER_TMR_CNT, 0);
1268 	GEM_WRITE_4(sc, GEM_MAC_PEAK_ATTEMPTS, 0);
1269 	GEM_WRITE_4(sc, GEM_MAC_RX_FRAME_COUNT, 0);
1270 	GEM_WRITE_4(sc, GEM_MAC_RX_LEN_ERR_CNT, 0);
1271 	GEM_WRITE_4(sc, GEM_MAC_RX_ALIGN_ERR, 0);
1272 	GEM_WRITE_4(sc, GEM_MAC_RX_CRC_ERR_CNT, 0);
1273 	GEM_WRITE_4(sc, GEM_MAC_RX_CODE_VIOL, 0);
1274 
1275 	/* Set XOFF PAUSE time. */
1276 	GEM_WRITE_4(sc, GEM_MAC_SEND_PAUSE_CMD, 0x1BF0);
1277 
1278 	/* Set the station address. */
1279 	GEM_WRITE_4(sc, GEM_MAC_ADDR0, (laddr[4] << 8) | laddr[5]);
1280 	GEM_WRITE_4(sc, GEM_MAC_ADDR1, (laddr[2] << 8) | laddr[3]);
1281 	GEM_WRITE_4(sc, GEM_MAC_ADDR2, (laddr[0] << 8) | laddr[1]);
1282 
1283 	/* Enable MII outputs. */
1284 	GEM_WRITE_4(sc, GEM_MAC_XIF_CONFIG, GEM_MAC_XIF_TX_MII_ENA);
1285 }
1286 
1287 static void
1288 gem_start(if_t ifp)
1289 {
1290 	struct gem_softc *sc = if_getsoftc(ifp);
1291 
1292 	GEM_LOCK(sc);
1293 	gem_start_locked(ifp);
1294 	GEM_UNLOCK(sc);
1295 }
1296 
1297 static inline void
1298 gem_txkick(struct gem_softc *sc)
1299 {
1300 
1301 	/*
1302 	 * Update the TX kick register.  This register has to point to the
1303 	 * descriptor after the last valid one and for optimum performance
1304 	 * should be incremented in multiples of 4 (the DMA engine fetches/
1305 	 * updates descriptors in batches of 4).
1306 	 */
1307 #ifdef GEM_DEBUG
1308 	CTR3(KTR_GEM, "%s: %s: kicking TX %d",
1309 	    device_get_name(sc->sc_dev), __func__, sc->sc_txnext);
1310 #endif
1311 	GEM_CDSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1312 	GEM_WRITE_4(sc, GEM_TX_KICK, sc->sc_txnext);
1313 }
1314 
1315 static void
1316 gem_start_locked(if_t ifp)
1317 {
1318 	struct gem_softc *sc = if_getsoftc(ifp);
1319 	struct mbuf *m;
1320 	int kicked, ntx;
1321 
1322 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1323 
1324 	if ((if_getdrvflags(ifp) & (IFF_DRV_RUNNING | IFF_DRV_OACTIVE)) !=
1325 	    IFF_DRV_RUNNING || (sc->sc_flags & GEM_LINK) == 0)
1326 		return;
1327 
1328 #ifdef GEM_DEBUG
1329 	CTR4(KTR_GEM, "%s: %s: txfree %d, txnext %d",
1330 	    device_get_name(sc->sc_dev), __func__, sc->sc_txfree,
1331 	    sc->sc_txnext);
1332 #endif
1333 	ntx = 0;
1334 	kicked = 0;
1335 	for (; !if_sendq_empty(ifp) && sc->sc_txfree > 1;) {
1336 		m = if_dequeue(ifp);
1337 		if (m == NULL)
1338 			break;
1339 		if (gem_load_txmbuf(sc, &m) != 0) {
1340 			if (m == NULL)
1341 				break;
1342 			if_setdrvflagbits(ifp, IFF_DRV_OACTIVE, 0);
1343 			if_sendq_prepend(ifp, m);
1344 			break;
1345 		}
1346 		if ((sc->sc_txnext % 4) == 0) {
1347 			gem_txkick(sc);
1348 			kicked = 1;
1349 		} else
1350 			kicked = 0;
1351 		ntx++;
1352 		BPF_MTAP(ifp, m);
1353 	}
1354 
1355 	if (ntx > 0) {
1356 		if (kicked == 0)
1357 			gem_txkick(sc);
1358 #ifdef GEM_DEBUG
1359 		CTR2(KTR_GEM, "%s: packets enqueued, OWN on %d",
1360 		    device_get_name(sc->sc_dev), sc->sc_txnext);
1361 #endif
1362 
1363 		/* Set a watchdog timer in case the chip flakes out. */
1364 		sc->sc_wdog_timer = 5;
1365 #ifdef GEM_DEBUG
1366 		CTR3(KTR_GEM, "%s: %s: watchdog %d",
1367 		    device_get_name(sc->sc_dev), __func__,
1368 		    sc->sc_wdog_timer);
1369 #endif
1370 	}
1371 }
1372 
1373 static void
1374 gem_tint(struct gem_softc *sc)
1375 {
1376 	if_t ifp = sc->sc_ifp;
1377 	struct gem_txsoft *txs;
1378 	int progress;
1379 	uint32_t txlast;
1380 #ifdef GEM_DEBUG
1381 	int i;
1382 
1383 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1384 
1385 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
1386 #endif
1387 
1388 	/*
1389 	 * Go through our TX list and free mbufs for those
1390 	 * frames that have been transmitted.
1391 	 */
1392 	progress = 0;
1393 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD);
1394 	while ((txs = STAILQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
1395 #ifdef GEM_DEBUG
1396 		if ((if_getflags(ifp) & IFF_DEBUG) != 0) {
1397 			printf("    txsoft %p transmit chain:\n", txs);
1398 			for (i = txs->txs_firstdesc;; i = GEM_NEXTTX(i)) {
1399 				printf("descriptor %d: ", i);
1400 				printf("gd_flags: 0x%016llx\t",
1401 				    (long long)le64toh(
1402 				    sc->sc_txdescs[i].gd_flags));
1403 				printf("gd_addr: 0x%016llx\n",
1404 				    (long long)le64toh(
1405 				    sc->sc_txdescs[i].gd_addr));
1406 				if (i == txs->txs_lastdesc)
1407 					break;
1408 			}
1409 		}
1410 #endif
1411 
1412 		/*
1413 		 * In theory, we could harvest some descriptors before
1414 		 * the ring is empty, but that's a bit complicated.
1415 		 *
1416 		 * GEM_TX_COMPLETION points to the last descriptor
1417 		 * processed + 1.
1418 		 */
1419 		txlast = GEM_READ_4(sc, GEM_TX_COMPLETION);
1420 #ifdef GEM_DEBUG
1421 		CTR4(KTR_GEM, "%s: txs->txs_firstdesc = %d, "
1422 		    "txs->txs_lastdesc = %d, txlast = %d",
1423 		    __func__, txs->txs_firstdesc, txs->txs_lastdesc, txlast);
1424 #endif
1425 		if (txs->txs_firstdesc <= txs->txs_lastdesc) {
1426 			if ((txlast >= txs->txs_firstdesc) &&
1427 			    (txlast <= txs->txs_lastdesc))
1428 				break;
1429 		} else {
1430 			/* Ick -- this command wraps. */
1431 			if ((txlast >= txs->txs_firstdesc) ||
1432 			    (txlast <= txs->txs_lastdesc))
1433 				break;
1434 		}
1435 
1436 #ifdef GEM_DEBUG
1437 		CTR1(KTR_GEM, "%s: releasing a descriptor", __func__);
1438 #endif
1439 		STAILQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
1440 
1441 		sc->sc_txfree += txs->txs_ndescs;
1442 
1443 		bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
1444 		    BUS_DMASYNC_POSTWRITE);
1445 		bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
1446 		if (txs->txs_mbuf != NULL) {
1447 			m_freem(txs->txs_mbuf);
1448 			txs->txs_mbuf = NULL;
1449 		}
1450 
1451 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
1452 
1453 		if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
1454 		progress = 1;
1455 	}
1456 
1457 #ifdef GEM_DEBUG
1458 	CTR4(KTR_GEM, "%s: GEM_TX_STATE_MACHINE %x GEM_TX_DATA_PTR %llx "
1459 	    "GEM_TX_COMPLETION %x",
1460 	    __func__, GEM_READ_4(sc, GEM_TX_STATE_MACHINE),
1461 	    ((long long)GEM_READ_4(sc, GEM_TX_DATA_PTR_HI) << 32) |
1462 	    GEM_READ_4(sc, GEM_TX_DATA_PTR_LO),
1463 	    GEM_READ_4(sc, GEM_TX_COMPLETION));
1464 #endif
1465 
1466 	if (progress) {
1467 		if (sc->sc_txfree == GEM_NTXDESC - 1)
1468 			sc->sc_txwin = 0;
1469 
1470 		/*
1471 		 * We freed some descriptors, so reset IFF_DRV_OACTIVE
1472 		 * and restart.
1473 		 */
1474 		if_setdrvflagbits(ifp, 0, IFF_DRV_OACTIVE);
1475 		if (STAILQ_EMPTY(&sc->sc_txdirtyq))
1476 		    sc->sc_wdog_timer = 0;
1477 		gem_start_locked(ifp);
1478 	}
1479 
1480 #ifdef GEM_DEBUG
1481 	CTR3(KTR_GEM, "%s: %s: watchdog %d",
1482 	    device_get_name(sc->sc_dev), __func__, sc->sc_wdog_timer);
1483 #endif
1484 }
1485 
1486 #ifdef GEM_RINT_TIMEOUT
1487 static void
1488 gem_rint_timeout(void *arg)
1489 {
1490 	struct gem_softc *sc = arg;
1491 
1492 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1493 
1494 	gem_rint(sc);
1495 }
1496 #endif
1497 
1498 static void
1499 gem_rint(struct gem_softc *sc)
1500 {
1501 	if_t ifp = sc->sc_ifp;
1502 	struct mbuf *m;
1503 	uint64_t rxstat;
1504 	uint32_t rxcomp;
1505 
1506 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1507 
1508 #ifdef GEM_RINT_TIMEOUT
1509 	callout_stop(&sc->sc_rx_ch);
1510 #endif
1511 #ifdef GEM_DEBUG
1512 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
1513 #endif
1514 
1515 	/*
1516 	 * Read the completion register once.  This limits
1517 	 * how long the following loop can execute.
1518 	 */
1519 	rxcomp = GEM_READ_4(sc, GEM_RX_COMPLETION);
1520 #ifdef GEM_DEBUG
1521 	CTR3(KTR_GEM, "%s: sc->sc_rxptr %d, complete %d",
1522 	    __func__, sc->sc_rxptr, rxcomp);
1523 #endif
1524 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
1525 	for (; sc->sc_rxptr != rxcomp;) {
1526 		m = sc->sc_rxsoft[sc->sc_rxptr].rxs_mbuf;
1527 		rxstat = le64toh(sc->sc_rxdescs[sc->sc_rxptr].gd_flags);
1528 
1529 		if (rxstat & GEM_RD_OWN) {
1530 #ifdef GEM_RINT_TIMEOUT
1531 			/*
1532 			 * The descriptor is still marked as owned, although
1533 			 * it is supposed to have completed.  This has been
1534 			 * observed on some machines.  Just exiting here
1535 			 * might leave the packet sitting around until another
1536 			 * one arrives to trigger a new interrupt, which is
1537 			 * generally undesirable, so set up a timeout.
1538 			 */
1539 			callout_reset(&sc->sc_rx_ch, GEM_RXOWN_TICKS,
1540 			    gem_rint_timeout, sc);
1541 #endif
1542 			m = NULL;
1543 			goto kickit;
1544 		}
1545 
1546 		if (rxstat & GEM_RD_BAD_CRC) {
1547 			if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
1548 			device_printf(sc->sc_dev, "receive error: CRC error\n");
1549 			GEM_INIT_RXDESC(sc, sc->sc_rxptr);
1550 			m = NULL;
1551 			goto kickit;
1552 		}
1553 
1554 #ifdef GEM_DEBUG
1555 		if ((if_getflags(ifp) & IFF_DEBUG) != 0) {
1556 			printf("    rxsoft %p descriptor %d: ",
1557 			    &sc->sc_rxsoft[sc->sc_rxptr], sc->sc_rxptr);
1558 			printf("gd_flags: 0x%016llx\t",
1559 			    (long long)le64toh(
1560 			    sc->sc_rxdescs[sc->sc_rxptr].gd_flags));
1561 			printf("gd_addr: 0x%016llx\n",
1562 			    (long long)le64toh(
1563 			    sc->sc_rxdescs[sc->sc_rxptr].gd_addr));
1564 		}
1565 #endif
1566 
1567 		/*
1568 		 * Allocate a new mbuf cluster.  If that fails, we are
1569 		 * out of memory, and must drop the packet and recycle
1570 		 * the buffer that's already attached to this descriptor.
1571 		 */
1572 		if (gem_add_rxbuf(sc, sc->sc_rxptr) != 0) {
1573 			if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1);
1574 			GEM_INIT_RXDESC(sc, sc->sc_rxptr);
1575 			m = NULL;
1576 		}
1577 
1578  kickit:
1579 		/*
1580 		 * Update the RX kick register.  This register has to point
1581 		 * to the descriptor after the last valid one (before the
1582 		 * current batch) and for optimum performance should be
1583 		 * incremented in multiples of 4 (the DMA engine fetches/
1584 		 * updates descriptors in batches of 4).
1585 		 */
1586 		sc->sc_rxptr = GEM_NEXTRX(sc->sc_rxptr);
1587 		if ((sc->sc_rxptr % 4) == 0) {
1588 			GEM_CDSYNC(sc,
1589 			    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1590 			GEM_WRITE_4(sc, GEM_RX_KICK,
1591 			    (sc->sc_rxptr + GEM_NRXDESC - 4) &
1592 			    GEM_NRXDESC_MASK);
1593 		}
1594 
1595 		if (m == NULL) {
1596 			if (rxstat & GEM_RD_OWN)
1597 				break;
1598 			continue;
1599 		}
1600 
1601 		if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
1602 		m->m_data += ETHER_ALIGN; /* first byte offset */
1603 		m->m_pkthdr.rcvif = ifp;
1604 		m->m_pkthdr.len = m->m_len = GEM_RD_BUFLEN(rxstat);
1605 
1606 		if ((if_getcapenable(ifp) & IFCAP_RXCSUM) != 0)
1607 			gem_rxcksum(m, rxstat);
1608 
1609 		/* Pass it on. */
1610 		GEM_UNLOCK(sc);
1611 		if_input(ifp, m);
1612 		GEM_LOCK(sc);
1613 	}
1614 
1615 #ifdef GEM_DEBUG
1616 	CTR3(KTR_GEM, "%s: done sc->sc_rxptr %d, complete %d", __func__,
1617 	    sc->sc_rxptr, GEM_READ_4(sc, GEM_RX_COMPLETION));
1618 #endif
1619 }
1620 
1621 static int
1622 gem_add_rxbuf(struct gem_softc *sc, int idx)
1623 {
1624 	struct gem_rxsoft *rxs = &sc->sc_rxsoft[idx];
1625 	struct mbuf *m;
1626 	bus_dma_segment_t segs[1];
1627 	int error, nsegs;
1628 
1629 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1630 
1631 	m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
1632 	if (m == NULL)
1633 		return (ENOBUFS);
1634 	m->m_len = m->m_pkthdr.len = m->m_ext.ext_size;
1635 
1636 #ifdef GEM_DEBUG
1637 	/* Bzero the packet to check DMA. */
1638 	memset(m->m_ext.ext_buf, 0, m->m_ext.ext_size);
1639 #endif
1640 
1641 	if (rxs->rxs_mbuf != NULL) {
1642 		bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
1643 		    BUS_DMASYNC_POSTREAD);
1644 		bus_dmamap_unload(sc->sc_rdmatag, rxs->rxs_dmamap);
1645 	}
1646 
1647 	error = bus_dmamap_load_mbuf_sg(sc->sc_rdmatag, rxs->rxs_dmamap,
1648 	    m, segs, &nsegs, BUS_DMA_NOWAIT);
1649 	if (error != 0) {
1650 		device_printf(sc->sc_dev,
1651 		    "cannot load RS DMA map %d, error = %d\n", idx, error);
1652 		m_freem(m);
1653 		return (error);
1654 	}
1655 	/* If nsegs is wrong then the stack is corrupt. */
1656 	KASSERT(nsegs == 1,
1657 	    ("%s: too many DMA segments (%d)", __func__, nsegs));
1658 	rxs->rxs_mbuf = m;
1659 	rxs->rxs_paddr = segs[0].ds_addr;
1660 
1661 	bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
1662 	    BUS_DMASYNC_PREREAD);
1663 
1664 	GEM_INIT_RXDESC(sc, idx);
1665 
1666 	return (0);
1667 }
1668 
1669 static void
1670 gem_eint(struct gem_softc *sc, u_int status)
1671 {
1672 
1673 	if_inc_counter(sc->sc_ifp, IFCOUNTER_IERRORS, 1);
1674 	if ((status & GEM_INTR_RX_TAG_ERR) != 0) {
1675 		gem_reset_rxdma(sc);
1676 		return;
1677 	}
1678 
1679 	device_printf(sc->sc_dev, "%s: status 0x%x", __func__, status);
1680 	if ((status & GEM_INTR_BERR) != 0) {
1681 		printf(", PCI bus error 0x%x",
1682 		    GEM_READ_4(sc, GEM_PCI_ERROR_STATUS));
1683 	}
1684 	printf("\n");
1685 }
1686 
1687 void
1688 gem_intr(void *v)
1689 {
1690 	struct gem_softc *sc = v;
1691 	uint32_t status, status2;
1692 
1693 	GEM_LOCK(sc);
1694 	status = GEM_READ_4(sc, GEM_STATUS);
1695 
1696 #ifdef GEM_DEBUG
1697 	CTR4(KTR_GEM, "%s: %s: cplt %x, status %x",
1698 	    device_get_name(sc->sc_dev), __func__,
1699 	    (status >> GEM_STATUS_TX_COMPLETION_SHFT), (u_int)status);
1700 
1701 	/*
1702 	 * PCS interrupts must be cleared, otherwise no traffic is passed!
1703 	 */
1704 	if ((status & GEM_INTR_PCS) != 0) {
1705 		status2 =
1706 		    GEM_READ_4(sc, GEM_MII_INTERRUP_STATUS) |
1707 		    GEM_READ_4(sc, GEM_MII_INTERRUP_STATUS);
1708 		if ((status2 & GEM_MII_INTERRUP_LINK) != 0)
1709 			device_printf(sc->sc_dev,
1710 			    "%s: PCS link status changed\n", __func__);
1711 	}
1712 	if ((status & GEM_MAC_CONTROL_STATUS) != 0) {
1713 		status2 = GEM_READ_4(sc, GEM_MAC_CONTROL_STATUS);
1714 		if ((status2 & GEM_MAC_PAUSED) != 0)
1715 			device_printf(sc->sc_dev,
1716 			    "%s: PAUSE received (PAUSE time %d slots)\n",
1717 			    __func__, GEM_MAC_PAUSE_TIME(status2));
1718 		if ((status2 & GEM_MAC_PAUSE) != 0)
1719 			device_printf(sc->sc_dev,
1720 			    "%s: transited to PAUSE state\n", __func__);
1721 		if ((status2 & GEM_MAC_RESUME) != 0)
1722 			device_printf(sc->sc_dev,
1723 			    "%s: transited to non-PAUSE state\n", __func__);
1724 	}
1725 	if ((status & GEM_INTR_MIF) != 0)
1726 		device_printf(sc->sc_dev, "%s: MIF interrupt\n", __func__);
1727 #endif
1728 
1729 	if (__predict_false(status &
1730 	    (GEM_INTR_RX_TAG_ERR | GEM_INTR_PERR | GEM_INTR_BERR)) != 0)
1731 		gem_eint(sc, status);
1732 
1733 	if ((status & (GEM_INTR_RX_DONE | GEM_INTR_RX_NOBUF)) != 0)
1734 		gem_rint(sc);
1735 
1736 	if ((status & (GEM_INTR_TX_EMPTY | GEM_INTR_TX_INTME)) != 0)
1737 		gem_tint(sc);
1738 
1739 	if (__predict_false((status & GEM_INTR_TX_MAC) != 0)) {
1740 		status2 = GEM_READ_4(sc, GEM_MAC_TX_STATUS);
1741 		if ((status2 &
1742 		    ~(GEM_MAC_TX_XMIT_DONE | GEM_MAC_TX_DEFER_EXP |
1743 		    GEM_MAC_TX_PEAK_EXP)) != 0)
1744 			device_printf(sc->sc_dev,
1745 			    "MAC TX fault, status %x\n", status2);
1746 		if ((status2 &
1747 		    (GEM_MAC_TX_UNDERRUN | GEM_MAC_TX_PKT_TOO_LONG)) != 0) {
1748 			if_inc_counter(sc->sc_ifp, IFCOUNTER_OERRORS, 1);
1749 			if_setdrvflagbits(sc->sc_ifp, 0, IFF_DRV_RUNNING);
1750 			gem_init_locked(sc);
1751 		}
1752 	}
1753 	if (__predict_false((status & GEM_INTR_RX_MAC) != 0)) {
1754 		status2 = GEM_READ_4(sc, GEM_MAC_RX_STATUS);
1755 		/*
1756 		 * At least with GEM_SUN_GEM revisions GEM_MAC_RX_OVERFLOW
1757 		 * happen often due to a silicon bug so handle them silently.
1758 		 * Moreover, it's likely that the receiver has hung so we
1759 		 * reset it.
1760 		 */
1761 		if ((status2 & GEM_MAC_RX_OVERFLOW) != 0) {
1762 			if_inc_counter(sc->sc_ifp, IFCOUNTER_IERRORS, 1);
1763 			gem_reset_rxdma(sc);
1764 		} else if ((status2 &
1765 		    ~(GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT)) != 0)
1766 			device_printf(sc->sc_dev,
1767 			    "MAC RX fault, status %x\n", status2);
1768 	}
1769 	GEM_UNLOCK(sc);
1770 }
1771 
1772 static int
1773 gem_watchdog(struct gem_softc *sc)
1774 {
1775 	if_t ifp = sc->sc_ifp;
1776 
1777 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1778 
1779 #ifdef GEM_DEBUG
1780 	CTR4(KTR_GEM,
1781 	    "%s: GEM_RX_CONFIG %x GEM_MAC_RX_STATUS %x GEM_MAC_RX_CONFIG %x",
1782 	    __func__, GEM_READ_4(sc, GEM_RX_CONFIG),
1783 	    GEM_READ_4(sc, GEM_MAC_RX_STATUS),
1784 	    GEM_READ_4(sc, GEM_MAC_RX_CONFIG));
1785 	CTR4(KTR_GEM,
1786 	    "%s: GEM_TX_CONFIG %x GEM_MAC_TX_STATUS %x GEM_MAC_TX_CONFIG %x",
1787 	    __func__, GEM_READ_4(sc, GEM_TX_CONFIG),
1788 	    GEM_READ_4(sc, GEM_MAC_TX_STATUS),
1789 	    GEM_READ_4(sc, GEM_MAC_TX_CONFIG));
1790 #endif
1791 
1792 	if (sc->sc_wdog_timer == 0 || --sc->sc_wdog_timer != 0)
1793 		return (0);
1794 
1795 	if ((sc->sc_flags & GEM_LINK) != 0)
1796 		device_printf(sc->sc_dev, "device timeout\n");
1797 	else if (bootverbose)
1798 		device_printf(sc->sc_dev, "device timeout (no link)\n");
1799 	if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
1800 
1801 	/* Try to get more packets going. */
1802 	if_setdrvflagbits(ifp, 0, IFF_DRV_RUNNING);
1803 	gem_init_locked(sc);
1804 	gem_start_locked(ifp);
1805 	return (EJUSTRETURN);
1806 }
1807 
1808 static void
1809 gem_mifinit(struct gem_softc *sc)
1810 {
1811 
1812 	/* Configure the MIF in frame mode. */
1813 	GEM_WRITE_4(sc, GEM_MIF_CONFIG,
1814 	    GEM_READ_4(sc, GEM_MIF_CONFIG) & ~GEM_MIF_CONFIG_BB_ENA);
1815 	GEM_BARRIER(sc, GEM_MIF_CONFIG, 4,
1816 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1817 }
1818 
1819 /*
1820  * MII interface
1821  *
1822  * The MII interface supports at least three different operating modes:
1823  *
1824  * Bitbang mode is implemented using data, clock and output enable registers.
1825  *
1826  * Frame mode is implemented by loading a complete frame into the frame
1827  * register and polling the valid bit for completion.
1828  *
1829  * Polling mode uses the frame register but completion is indicated by
1830  * an interrupt.
1831  *
1832  */
1833 int
1834 gem_mii_readreg(device_t dev, int phy, int reg)
1835 {
1836 	struct gem_softc *sc;
1837 	int n;
1838 	uint32_t v;
1839 
1840 #ifdef GEM_DEBUG_PHY
1841 	printf("%s: phy %d reg %d\n", __func__, phy, reg);
1842 #endif
1843 
1844 	sc = device_get_softc(dev);
1845 	if ((sc->sc_flags & GEM_SERDES) != 0) {
1846 		switch (reg) {
1847 		case MII_BMCR:
1848 			reg = GEM_MII_CONTROL;
1849 			break;
1850 		case MII_BMSR:
1851 			reg = GEM_MII_STATUS;
1852 			break;
1853 		case MII_PHYIDR1:
1854 		case MII_PHYIDR2:
1855 			return (0);
1856 		case MII_ANAR:
1857 			reg = GEM_MII_ANAR;
1858 			break;
1859 		case MII_ANLPAR:
1860 			reg = GEM_MII_ANLPAR;
1861 			break;
1862 		case MII_EXTSR:
1863 			return (EXTSR_1000XFDX | EXTSR_1000XHDX);
1864 		default:
1865 			device_printf(sc->sc_dev,
1866 			    "%s: unhandled register %d\n", __func__, reg);
1867 			return (0);
1868 		}
1869 		return (GEM_READ_4(sc, reg));
1870 	}
1871 
1872 	/* Construct the frame command. */
1873 	v = GEM_MIF_FRAME_READ |
1874 	    (phy << GEM_MIF_PHY_SHIFT) |
1875 	    (reg << GEM_MIF_REG_SHIFT);
1876 
1877 	GEM_WRITE_4(sc, GEM_MIF_FRAME, v);
1878 	GEM_BARRIER(sc, GEM_MIF_FRAME, 4,
1879 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1880 	for (n = 0; n < 100; n++) {
1881 		DELAY(1);
1882 		v = GEM_READ_4(sc, GEM_MIF_FRAME);
1883 		if (v & GEM_MIF_FRAME_TA0)
1884 			return (v & GEM_MIF_FRAME_DATA);
1885 	}
1886 
1887 	device_printf(sc->sc_dev, "%s: timed out\n", __func__);
1888 	return (0);
1889 }
1890 
1891 int
1892 gem_mii_writereg(device_t dev, int phy, int reg, int val)
1893 {
1894 	struct gem_softc *sc;
1895 	int n;
1896 	uint32_t v;
1897 
1898 #ifdef GEM_DEBUG_PHY
1899 	printf("%s: phy %d reg %d val %x\n", phy, reg, val, __func__);
1900 #endif
1901 
1902 	sc = device_get_softc(dev);
1903 	if ((sc->sc_flags & GEM_SERDES) != 0) {
1904 		switch (reg) {
1905 		case MII_BMSR:
1906 			reg = GEM_MII_STATUS;
1907 			break;
1908 		case MII_BMCR:
1909 			reg = GEM_MII_CONTROL;
1910 			if ((val & GEM_MII_CONTROL_RESET) == 0)
1911 				break;
1912 			GEM_WRITE_4(sc, GEM_MII_CONTROL, val);
1913 			GEM_BARRIER(sc, GEM_MII_CONTROL, 4,
1914 			    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1915 			if (!gem_bitwait(sc, GEM_MII_CONTROL,
1916 			    GEM_MII_CONTROL_RESET, 0))
1917 				device_printf(sc->sc_dev,
1918 				    "cannot reset PCS\n");
1919 			/* FALLTHROUGH */
1920 		case MII_ANAR:
1921 			GEM_WRITE_4(sc, GEM_MII_CONFIG, 0);
1922 			GEM_BARRIER(sc, GEM_MII_CONFIG, 4,
1923 			    BUS_SPACE_BARRIER_WRITE);
1924 			GEM_WRITE_4(sc, GEM_MII_ANAR, val);
1925 			GEM_BARRIER(sc, GEM_MII_ANAR, 4,
1926 			    BUS_SPACE_BARRIER_WRITE);
1927 			GEM_WRITE_4(sc, GEM_MII_SLINK_CONTROL,
1928 			    GEM_MII_SLINK_LOOPBACK | GEM_MII_SLINK_EN_SYNC_D);
1929 			GEM_BARRIER(sc, GEM_MII_SLINK_CONTROL, 4,
1930 			    BUS_SPACE_BARRIER_WRITE);
1931 			GEM_WRITE_4(sc, GEM_MII_CONFIG,
1932 			    GEM_MII_CONFIG_ENABLE);
1933 			GEM_BARRIER(sc, GEM_MII_CONFIG, 4,
1934 			    BUS_SPACE_BARRIER_WRITE);
1935 			return (0);
1936 		case MII_ANLPAR:
1937 			reg = GEM_MII_ANLPAR;
1938 			break;
1939 		default:
1940 			device_printf(sc->sc_dev,
1941 			    "%s: unhandled register %d\n", __func__, reg);
1942 			return (0);
1943 		}
1944 		GEM_WRITE_4(sc, reg, val);
1945 		GEM_BARRIER(sc, reg, 4,
1946 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1947 		return (0);
1948 	}
1949 
1950 	/* Construct the frame command. */
1951 	v = GEM_MIF_FRAME_WRITE |
1952 	    (phy << GEM_MIF_PHY_SHIFT) |
1953 	    (reg << GEM_MIF_REG_SHIFT) |
1954 	    (val & GEM_MIF_FRAME_DATA);
1955 
1956 	GEM_WRITE_4(sc, GEM_MIF_FRAME, v);
1957 	GEM_BARRIER(sc, GEM_MIF_FRAME, 4,
1958 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1959 	for (n = 0; n < 100; n++) {
1960 		DELAY(1);
1961 		v = GEM_READ_4(sc, GEM_MIF_FRAME);
1962 		if (v & GEM_MIF_FRAME_TA0)
1963 			return (1);
1964 	}
1965 
1966 	device_printf(sc->sc_dev, "%s: timed out\n", __func__);
1967 	return (0);
1968 }
1969 
1970 void
1971 gem_mii_statchg(device_t dev)
1972 {
1973 	struct gem_softc *sc;
1974 	int gigabit;
1975 	uint32_t rxcfg, txcfg, v;
1976 
1977 	sc = device_get_softc(dev);
1978 
1979 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1980 
1981 #ifdef GEM_DEBUG
1982 	if ((sc->sc_if_getflags(ifp) & IFF_DEBUG) != 0)
1983 		device_printf(sc->sc_dev, "%s: status change\n", __func__);
1984 #endif
1985 
1986 	if ((sc->sc_mii->mii_media_status & IFM_ACTIVE) != 0 &&
1987 	    IFM_SUBTYPE(sc->sc_mii->mii_media_active) != IFM_NONE)
1988 		sc->sc_flags |= GEM_LINK;
1989 	else
1990 		sc->sc_flags &= ~GEM_LINK;
1991 
1992 	switch (IFM_SUBTYPE(sc->sc_mii->mii_media_active)) {
1993 	case IFM_1000_SX:
1994 	case IFM_1000_LX:
1995 	case IFM_1000_CX:
1996 	case IFM_1000_T:
1997 		gigabit = 1;
1998 		break;
1999 	default:
2000 		gigabit = 0;
2001 	}
2002 
2003 	/*
2004 	 * The configuration done here corresponds to the steps F) and
2005 	 * G) and as far as enabling of RX and TX MAC goes also step H)
2006 	 * of the initialization sequence outlined in section 3.2.1 of
2007 	 * the GEM Gigabit Ethernet ASIC Specification.
2008 	 */
2009 
2010 	rxcfg = sc->sc_mac_rxcfg;
2011 	rxcfg &= ~GEM_MAC_RX_CARR_EXTEND;
2012 	txcfg = GEM_MAC_TX_ENA_IPG0 | GEM_MAC_TX_NGU | GEM_MAC_TX_NGU_LIMIT;
2013 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) != 0)
2014 		txcfg |= GEM_MAC_TX_IGN_CARRIER | GEM_MAC_TX_IGN_COLLIS;
2015 	else if (gigabit != 0) {
2016 		rxcfg |= GEM_MAC_RX_CARR_EXTEND;
2017 		txcfg |= GEM_MAC_TX_CARR_EXTEND;
2018 	}
2019 	(void)gem_disable_tx(sc);
2020 	GEM_WRITE_4(sc, GEM_MAC_TX_CONFIG, txcfg);
2021 	(void)gem_disable_rx(sc);
2022 	GEM_WRITE_4(sc, GEM_MAC_RX_CONFIG, rxcfg);
2023 
2024 	v = GEM_READ_4(sc, GEM_MAC_CONTROL_CONFIG) &
2025 	    ~(GEM_MAC_CC_RX_PAUSE | GEM_MAC_CC_TX_PAUSE);
2026 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
2027 	    IFM_ETH_RXPAUSE) != 0)
2028 		v |= GEM_MAC_CC_RX_PAUSE;
2029 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
2030 	    IFM_ETH_TXPAUSE) != 0)
2031 		v |= GEM_MAC_CC_TX_PAUSE;
2032 	GEM_WRITE_4(sc, GEM_MAC_CONTROL_CONFIG, v);
2033 
2034 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) == 0 &&
2035 	    gigabit != 0)
2036 		GEM_WRITE_4(sc, GEM_MAC_SLOT_TIME,
2037 		    GEM_MAC_SLOT_TIME_CARR_EXTEND);
2038 	else
2039 		GEM_WRITE_4(sc, GEM_MAC_SLOT_TIME,
2040 		    GEM_MAC_SLOT_TIME_NORMAL);
2041 
2042 	/* XIF Configuration */
2043 	v = GEM_MAC_XIF_LINK_LED;
2044 	v |= GEM_MAC_XIF_TX_MII_ENA;
2045 	if ((sc->sc_flags & GEM_SERDES) == 0) {
2046 		if ((GEM_READ_4(sc, GEM_MIF_CONFIG) &
2047 		    GEM_MIF_CONFIG_PHY_SEL) != 0) {
2048 			/* External MII needs echo disable if half duplex. */
2049 			if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
2050 			    IFM_FDX) == 0)
2051 				v |= GEM_MAC_XIF_ECHO_DISABL;
2052 		} else
2053 			/*
2054 			 * Internal MII needs buffer enable.
2055 			 * XXX buffer enable makes only sense for an
2056 			 * external PHY.
2057 			 */
2058 			v |= GEM_MAC_XIF_MII_BUF_ENA;
2059 	}
2060 	if (gigabit != 0)
2061 		v |= GEM_MAC_XIF_GMII_MODE;
2062 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) != 0)
2063 		v |= GEM_MAC_XIF_FDPLX_LED;
2064 	GEM_WRITE_4(sc, GEM_MAC_XIF_CONFIG, v);
2065 
2066 	sc->sc_mac_rxcfg = rxcfg;
2067 	if ((if_getdrvflags(sc->sc_ifp) & IFF_DRV_RUNNING) != 0 &&
2068 	    (sc->sc_flags & GEM_LINK) != 0) {
2069 		GEM_WRITE_4(sc, GEM_MAC_TX_CONFIG,
2070 		    txcfg | GEM_MAC_TX_ENABLE);
2071 		GEM_WRITE_4(sc, GEM_MAC_RX_CONFIG,
2072 		    rxcfg | GEM_MAC_RX_ENABLE);
2073 	}
2074 }
2075 
2076 int
2077 gem_mediachange(if_t ifp)
2078 {
2079 	struct gem_softc *sc = if_getsoftc(ifp);
2080 	int error;
2081 
2082 	/* XXX add support for serial media. */
2083 
2084 	GEM_LOCK(sc);
2085 	error = mii_mediachg(sc->sc_mii);
2086 	GEM_UNLOCK(sc);
2087 	return (error);
2088 }
2089 
2090 void
2091 gem_mediastatus(if_t ifp, struct ifmediareq *ifmr)
2092 {
2093 	struct gem_softc *sc = if_getsoftc(ifp);
2094 
2095 	GEM_LOCK(sc);
2096 	if ((if_getflags(ifp) & IFF_UP) == 0) {
2097 		GEM_UNLOCK(sc);
2098 		return;
2099 	}
2100 
2101 	mii_pollstat(sc->sc_mii);
2102 	ifmr->ifm_active = sc->sc_mii->mii_media_active;
2103 	ifmr->ifm_status = sc->sc_mii->mii_media_status;
2104 	GEM_UNLOCK(sc);
2105 }
2106 
2107 static int
2108 gem_ioctl(if_t ifp, u_long cmd, caddr_t data)
2109 {
2110 	struct gem_softc *sc = if_getsoftc(ifp);
2111 	struct ifreq *ifr = (struct ifreq *)data;
2112 	int error;
2113 
2114 	error = 0;
2115 	switch (cmd) {
2116 	case SIOCSIFFLAGS:
2117 		GEM_LOCK(sc);
2118 		if ((if_getflags(ifp) & IFF_UP) != 0) {
2119 			if ((if_getdrvflags(ifp) & IFF_DRV_RUNNING) != 0 &&
2120 			    ((if_getflags(ifp) ^ sc->sc_ifflags) &
2121 			    (IFF_ALLMULTI | IFF_PROMISC)) != 0)
2122 				gem_setladrf(sc);
2123 			else
2124 				gem_init_locked(sc);
2125 		} else if ((if_getdrvflags(ifp) & IFF_DRV_RUNNING) != 0)
2126 			gem_stop(ifp, 0);
2127 		if ((if_getflags(ifp) & IFF_LINK0) != 0)
2128 			sc->sc_csum_features |= CSUM_UDP;
2129 		else
2130 			sc->sc_csum_features &= ~CSUM_UDP;
2131 		if ((if_getcapenable(ifp) & IFCAP_TXCSUM) != 0)
2132 			if_sethwassist(ifp, sc->sc_csum_features);
2133 		sc->sc_ifflags = if_getflags(ifp);
2134 		GEM_UNLOCK(sc);
2135 		break;
2136 	case SIOCADDMULTI:
2137 	case SIOCDELMULTI:
2138 		GEM_LOCK(sc);
2139 		if ((if_getdrvflags(ifp) & IFF_DRV_RUNNING) != 0)
2140 			gem_setladrf(sc);
2141 		GEM_UNLOCK(sc);
2142 		break;
2143 	case SIOCGIFMEDIA:
2144 	case SIOCSIFMEDIA:
2145 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii->mii_media, cmd);
2146 		break;
2147 	case SIOCSIFCAP:
2148 		GEM_LOCK(sc);
2149 		if_setcapenable(ifp, ifr->ifr_reqcap);
2150 		if ((if_getcapenable(ifp) & IFCAP_TXCSUM) != 0)
2151 			if_sethwassist(ifp, sc->sc_csum_features);
2152 		else
2153 			if_sethwassist(ifp, 0);
2154 		GEM_UNLOCK(sc);
2155 		break;
2156 	default:
2157 		error = ether_ioctl(ifp, cmd, data);
2158 		break;
2159 	}
2160 
2161 	return (error);
2162 }
2163 
2164 static u_int
2165 gem_hash_maddr(void *arg, struct sockaddr_dl *sdl, u_int cnt)
2166 {
2167 	uint32_t crc, *hash = arg;
2168 
2169 	crc = ether_crc32_le(LLADDR(sdl), ETHER_ADDR_LEN);
2170 	/* We just want the 8 most significant bits. */
2171 	crc >>= 24;
2172 	/* Set the corresponding bit in the filter. */
2173 	hash[crc >> 4] |= 1 << (15 - (crc & 15));
2174 
2175 	return (1);
2176 }
2177 
2178 static void
2179 gem_setladrf(struct gem_softc *sc)
2180 {
2181 	if_t ifp = sc->sc_ifp;
2182 	int i;
2183 	uint32_t hash[16];
2184 	uint32_t v;
2185 
2186 	GEM_LOCK_ASSERT(sc, MA_OWNED);
2187 
2188 	/*
2189 	 * Turn off the RX MAC and the hash filter as required by the Sun GEM
2190 	 * programming restrictions.
2191 	 */
2192 	v = sc->sc_mac_rxcfg & ~GEM_MAC_RX_HASH_FILTER;
2193 	GEM_WRITE_4(sc, GEM_MAC_RX_CONFIG, v);
2194 	GEM_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
2195 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
2196 	if (!gem_bitwait(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_HASH_FILTER |
2197 	    GEM_MAC_RX_ENABLE, 0))
2198 		device_printf(sc->sc_dev,
2199 		    "cannot disable RX MAC or hash filter\n");
2200 
2201 	v &= ~(GEM_MAC_RX_PROMISCUOUS | GEM_MAC_RX_PROMISC_GRP);
2202 	if ((if_getflags(ifp) & IFF_PROMISC) != 0) {
2203 		v |= GEM_MAC_RX_PROMISCUOUS;
2204 		goto chipit;
2205 	}
2206 	if ((if_getflags(ifp) & IFF_ALLMULTI) != 0) {
2207 		v |= GEM_MAC_RX_PROMISC_GRP;
2208 		goto chipit;
2209 	}
2210 
2211 	/*
2212 	 * Set up multicast address filter by passing all multicast
2213 	 * addresses through a crc generator, and then using the high
2214 	 * order 8 bits as an index into the 256 bit logical address
2215 	 * filter.  The high order 4 bits selects the word, while the
2216 	 * other 4 bits select the bit within the word (where bit 0
2217 	 * is the MSB).
2218 	 */
2219 
2220 	memset(hash, 0, sizeof(hash));
2221 	if_foreach_llmaddr(ifp, gem_hash_maddr, hash);
2222 
2223 	v |= GEM_MAC_RX_HASH_FILTER;
2224 
2225 	/* Now load the hash table into the chip (if we are using it). */
2226 	for (i = 0; i < 16; i++)
2227 		GEM_WRITE_4(sc,
2228 		    GEM_MAC_HASH0 + i * (GEM_MAC_HASH1 - GEM_MAC_HASH0),
2229 		    hash[i]);
2230 
2231  chipit:
2232 	sc->sc_mac_rxcfg = v;
2233 	GEM_WRITE_4(sc, GEM_MAC_RX_CONFIG, v | GEM_MAC_RX_ENABLE);
2234 }
2235