xref: /freebsd/sys/dev/gem/if_gem.c (revision a0409676120c1e558d0ade943019934e0f15118d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-NetBSD
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 __FBSDID("$FreeBSD$");
35 
36 /*
37  * Driver for Apple GMAC, Sun ERI and Sun GEM Ethernet controllers
38  */
39 
40 #if 0
41 #define	GEM_DEBUG
42 #endif
43 
44 #if 0	/* XXX: In case of emergency, re-enable this. */
45 #define	GEM_RINT_TIMEOUT
46 #endif
47 
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/bus.h>
51 #include <sys/callout.h>
52 #include <sys/endian.h>
53 #include <sys/mbuf.h>
54 #include <sys/malloc.h>
55 #include <sys/kernel.h>
56 #include <sys/lock.h>
57 #include <sys/module.h>
58 #include <sys/mutex.h>
59 #include <sys/socket.h>
60 #include <sys/sockio.h>
61 #include <sys/rman.h>
62 
63 #include <net/bpf.h>
64 #include <net/ethernet.h>
65 #include <net/if.h>
66 #include <net/if_var.h>
67 #include <net/if_arp.h>
68 #include <net/if_dl.h>
69 #include <net/if_media.h>
70 #include <net/if_types.h>
71 #include <net/if_vlan_var.h>
72 
73 #include <netinet/in.h>
74 #include <netinet/in_systm.h>
75 #include <netinet/ip.h>
76 #include <netinet/tcp.h>
77 #include <netinet/udp.h>
78 
79 #include <machine/bus.h>
80 
81 #include <dev/mii/mii.h>
82 #include <dev/mii/miivar.h>
83 
84 #include <dev/gem/if_gemreg.h>
85 #include <dev/gem/if_gemvar.h>
86 
87 CTASSERT(powerof2(GEM_NRXDESC) && GEM_NRXDESC >= 32 && GEM_NRXDESC <= 8192);
88 CTASSERT(powerof2(GEM_NTXDESC) && GEM_NTXDESC >= 32 && GEM_NTXDESC <= 8192);
89 
90 #define	GEM_TRIES	10000
91 
92 /*
93  * The hardware supports basic TCP/UDP checksum offloading.  However,
94  * the hardware doesn't compensate the checksum for UDP datagram which
95  * can yield to 0x0.  As a safe guard, UDP checksum offload is disabled
96  * by default.  It can be reactivated by setting special link option
97  * link0 with ifconfig(8).
98  */
99 #define	GEM_CSUM_FEATURES	(CSUM_TCP)
100 
101 static int	gem_add_rxbuf(struct gem_softc *sc, int idx);
102 static int	gem_bitwait(struct gem_softc *sc, u_int bank, bus_addr_t r,
103 		    uint32_t clr, uint32_t set);
104 static void	gem_cddma_callback(void *xsc, bus_dma_segment_t *segs,
105 		    int nsegs, int error);
106 static int	gem_disable_rx(struct gem_softc *sc);
107 static int	gem_disable_tx(struct gem_softc *sc);
108 static void	gem_eint(struct gem_softc *sc, u_int status);
109 static void	gem_init(void *xsc);
110 static void	gem_init_locked(struct gem_softc *sc);
111 static void	gem_init_regs(struct gem_softc *sc);
112 static int	gem_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data);
113 static int	gem_load_txmbuf(struct gem_softc *sc, struct mbuf **m_head);
114 static int	gem_meminit(struct gem_softc *sc);
115 static void	gem_mifinit(struct gem_softc *sc);
116 static void	gem_reset(struct gem_softc *sc);
117 static int	gem_reset_rx(struct gem_softc *sc);
118 static void	gem_reset_rxdma(struct gem_softc *sc);
119 static int	gem_reset_tx(struct gem_softc *sc);
120 static u_int	gem_ringsize(u_int sz);
121 static void	gem_rint(struct gem_softc *sc);
122 #ifdef GEM_RINT_TIMEOUT
123 static void	gem_rint_timeout(void *arg);
124 #endif
125 static inline void gem_rxcksum(struct mbuf *m, uint64_t flags);
126 static void	gem_rxdrain(struct gem_softc *sc);
127 static void	gem_setladrf(struct gem_softc *sc);
128 static void	gem_start(struct ifnet *ifp);
129 static void	gem_start_locked(struct ifnet *ifp);
130 static void	gem_stop(struct ifnet *ifp, int disable);
131 static void	gem_tick(void *arg);
132 static void	gem_tint(struct gem_softc *sc);
133 static inline void gem_txkick(struct gem_softc *sc);
134 static int	gem_watchdog(struct gem_softc *sc);
135 
136 devclass_t gem_devclass;
137 DRIVER_MODULE(miibus, gem, miibus_driver, miibus_devclass, 0, 0);
138 MODULE_DEPEND(gem, miibus, 1, 1, 1);
139 
140 #ifdef GEM_DEBUG
141 #include <sys/ktr.h>
142 #define	KTR_GEM		KTR_SPARE2
143 #endif
144 
145 #define	GEM_BANK1_BITWAIT(sc, r, clr, set)				\
146 	gem_bitwait((sc), GEM_RES_BANK1, (r), (clr), (set))
147 #define	GEM_BANK2_BITWAIT(sc, r, clr, set)				\
148 	gem_bitwait((sc), GEM_RES_BANK2, (r), (clr), (set))
149 
150 int
151 gem_attach(struct gem_softc *sc)
152 {
153 	struct gem_txsoft *txs;
154 	struct ifnet *ifp;
155 	int error, i, phy;
156 	uint32_t v;
157 
158 	if (bootverbose)
159 		device_printf(sc->sc_dev, "flags=0x%x\n", sc->sc_flags);
160 
161 	/* Set up ifnet structure. */
162 	ifp = sc->sc_ifp = if_alloc(IFT_ETHER);
163 	if (ifp == NULL)
164 		return (ENOSPC);
165 	sc->sc_csum_features = GEM_CSUM_FEATURES;
166 	ifp->if_softc = sc;
167 	if_initname(ifp, device_get_name(sc->sc_dev),
168 	    device_get_unit(sc->sc_dev));
169 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
170 	ifp->if_start = gem_start;
171 	ifp->if_ioctl = gem_ioctl;
172 	ifp->if_init = gem_init;
173 	IFQ_SET_MAXLEN(&ifp->if_snd, GEM_TXQUEUELEN);
174 	ifp->if_snd.ifq_drv_maxlen = GEM_TXQUEUELEN;
175 	IFQ_SET_READY(&ifp->if_snd);
176 
177 	callout_init_mtx(&sc->sc_tick_ch, &sc->sc_mtx, 0);
178 #ifdef GEM_RINT_TIMEOUT
179 	callout_init_mtx(&sc->sc_rx_ch, &sc->sc_mtx, 0);
180 #endif
181 
182 	/* Make sure the chip is stopped. */
183 	gem_reset(sc);
184 
185 	error = bus_dma_tag_create(bus_get_dma_tag(sc->sc_dev), 1, 0,
186 	    BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL,
187 	    BUS_SPACE_MAXSIZE_32BIT, 0, BUS_SPACE_MAXSIZE_32BIT, 0, NULL,
188 	    NULL, &sc->sc_pdmatag);
189 	if (error != 0)
190 		goto fail_ifnet;
191 
192 	error = bus_dma_tag_create(sc->sc_pdmatag, 1, 0,
193 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL, MCLBYTES,
194 	    1, MCLBYTES, BUS_DMA_ALLOCNOW, NULL, NULL, &sc->sc_rdmatag);
195 	if (error != 0)
196 		goto fail_ptag;
197 
198 	error = bus_dma_tag_create(sc->sc_pdmatag, 1, 0,
199 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
200 	    MCLBYTES * GEM_NTXSEGS, GEM_NTXSEGS, MCLBYTES,
201 	    BUS_DMA_ALLOCNOW, NULL, NULL, &sc->sc_tdmatag);
202 	if (error != 0)
203 		goto fail_rtag;
204 
205 	error = bus_dma_tag_create(sc->sc_pdmatag, PAGE_SIZE, 0,
206 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
207 	    sizeof(struct gem_control_data), 1,
208 	    sizeof(struct gem_control_data), 0,
209 	    NULL, NULL, &sc->sc_cdmatag);
210 	if (error != 0)
211 		goto fail_ttag;
212 
213 	/*
214 	 * Allocate the control data structures, create and load the
215 	 * DMA map for it.
216 	 */
217 	if ((error = bus_dmamem_alloc(sc->sc_cdmatag,
218 	    (void **)&sc->sc_control_data,
219 	    BUS_DMA_WAITOK | BUS_DMA_COHERENT | BUS_DMA_ZERO,
220 	    &sc->sc_cddmamap)) != 0) {
221 		device_printf(sc->sc_dev,
222 		    "unable to allocate control data, error = %d\n", error);
223 		goto fail_ctag;
224 	}
225 
226 	sc->sc_cddma = 0;
227 	if ((error = bus_dmamap_load(sc->sc_cdmatag, sc->sc_cddmamap,
228 	    sc->sc_control_data, sizeof(struct gem_control_data),
229 	    gem_cddma_callback, sc, 0)) != 0 || sc->sc_cddma == 0) {
230 		device_printf(sc->sc_dev,
231 		    "unable to load control data DMA map, error = %d\n",
232 		    error);
233 		goto fail_cmem;
234 	}
235 
236 	/*
237 	 * Initialize the transmit job descriptors.
238 	 */
239 	STAILQ_INIT(&sc->sc_txfreeq);
240 	STAILQ_INIT(&sc->sc_txdirtyq);
241 
242 	/*
243 	 * Create the transmit buffer DMA maps.
244 	 */
245 	error = ENOMEM;
246 	for (i = 0; i < GEM_TXQUEUELEN; i++) {
247 		txs = &sc->sc_txsoft[i];
248 		txs->txs_mbuf = NULL;
249 		txs->txs_ndescs = 0;
250 		if ((error = bus_dmamap_create(sc->sc_tdmatag, 0,
251 		    &txs->txs_dmamap)) != 0) {
252 			device_printf(sc->sc_dev,
253 			    "unable to create TX DMA map %d, error = %d\n",
254 			    i, error);
255 			goto fail_txd;
256 		}
257 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
258 	}
259 
260 	/*
261 	 * Create the receive buffer DMA maps.
262 	 */
263 	for (i = 0; i < GEM_NRXDESC; i++) {
264 		if ((error = bus_dmamap_create(sc->sc_rdmatag, 0,
265 		    &sc->sc_rxsoft[i].rxs_dmamap)) != 0) {
266 			device_printf(sc->sc_dev,
267 			    "unable to create RX DMA map %d, error = %d\n",
268 			    i, error);
269 			goto fail_rxd;
270 		}
271 		sc->sc_rxsoft[i].rxs_mbuf = NULL;
272 	}
273 
274 	/* Bypass probing PHYs if we already know for sure to use a SERDES. */
275 	if ((sc->sc_flags & GEM_SERDES) != 0)
276 		goto serdes;
277 
278 	/* Bad things will happen when touching this register on ERI. */
279 	if (sc->sc_variant != GEM_SUN_ERI) {
280 		GEM_BANK1_WRITE_4(sc, GEM_MII_DATAPATH_MODE,
281 		    GEM_MII_DATAPATH_MII);
282 		GEM_BANK1_BARRIER(sc, GEM_MII_DATAPATH_MODE, 4,
283 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
284 	}
285 
286 	gem_mifinit(sc);
287 
288 	/*
289 	 * Look for an external PHY.
290 	 */
291 	error = ENXIO;
292 	v = GEM_BANK1_READ_4(sc, GEM_MIF_CONFIG);
293 	if ((v & GEM_MIF_CONFIG_MDI1) != 0) {
294 		v |= GEM_MIF_CONFIG_PHY_SEL;
295 		GEM_BANK1_WRITE_4(sc, GEM_MIF_CONFIG, v);
296 		GEM_BANK1_BARRIER(sc, GEM_MIF_CONFIG, 4,
297 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
298 		switch (sc->sc_variant) {
299 		case GEM_SUN_ERI:
300 			phy = GEM_PHYAD_EXTERNAL;
301 			break;
302 		default:
303 			phy = MII_PHY_ANY;
304 			break;
305 		}
306 		error = mii_attach(sc->sc_dev, &sc->sc_miibus, ifp,
307 		    gem_mediachange, gem_mediastatus, BMSR_DEFCAPMASK, phy,
308 		    MII_OFFSET_ANY, MIIF_DOPAUSE);
309 	}
310 
311 	/*
312 	 * Fall back on an internal PHY if no external PHY was found.
313 	 * Note that with Apple (K2) GMACs GEM_MIF_CONFIG_MDI0 can't be
314 	 * trusted when the firmware has powered down the chip.
315 	 */
316 	if (error != 0 &&
317 	    ((v & GEM_MIF_CONFIG_MDI0) != 0 || GEM_IS_APPLE(sc))) {
318 		v &= ~GEM_MIF_CONFIG_PHY_SEL;
319 		GEM_BANK1_WRITE_4(sc, GEM_MIF_CONFIG, v);
320 		GEM_BANK1_BARRIER(sc, GEM_MIF_CONFIG, 4,
321 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
322 		switch (sc->sc_variant) {
323 		case GEM_SUN_ERI:
324 		case GEM_APPLE_K2_GMAC:
325 			phy = GEM_PHYAD_INTERNAL;
326 			break;
327 		case GEM_APPLE_GMAC:
328 			phy = GEM_PHYAD_EXTERNAL;
329 			break;
330 		default:
331 			phy = MII_PHY_ANY;
332 			break;
333 		}
334 		error = mii_attach(sc->sc_dev, &sc->sc_miibus, ifp,
335 		    gem_mediachange, gem_mediastatus, BMSR_DEFCAPMASK, phy,
336 		    MII_OFFSET_ANY, MIIF_DOPAUSE);
337 	}
338 
339 	/*
340 	 * Try the external PCS SERDES if we didn't find any PHYs.
341 	 */
342 	if (error != 0 && sc->sc_variant == GEM_SUN_GEM) {
343  serdes:
344 		GEM_BANK1_WRITE_4(sc, GEM_MII_DATAPATH_MODE,
345 		    GEM_MII_DATAPATH_SERDES);
346 		GEM_BANK1_BARRIER(sc, GEM_MII_DATAPATH_MODE, 4,
347 		    BUS_SPACE_BARRIER_WRITE);
348 		GEM_BANK1_WRITE_4(sc, GEM_MII_SLINK_CONTROL,
349 		    GEM_MII_SLINK_LOOPBACK | GEM_MII_SLINK_EN_SYNC_D);
350 		GEM_BANK1_BARRIER(sc, GEM_MII_SLINK_CONTROL, 4,
351 		    BUS_SPACE_BARRIER_WRITE);
352 		GEM_BANK1_WRITE_4(sc, GEM_MII_CONFIG, GEM_MII_CONFIG_ENABLE);
353 		GEM_BANK1_BARRIER(sc, GEM_MII_CONFIG, 4,
354 		    BUS_SPACE_BARRIER_WRITE);
355 		sc->sc_flags |= GEM_SERDES;
356 		error = mii_attach(sc->sc_dev, &sc->sc_miibus, ifp,
357 		    gem_mediachange, gem_mediastatus, BMSR_DEFCAPMASK,
358 		    GEM_PHYAD_EXTERNAL, MII_OFFSET_ANY, MIIF_DOPAUSE);
359 	}
360 	if (error != 0) {
361 		device_printf(sc->sc_dev, "attaching PHYs failed\n");
362 		goto fail_rxd;
363 	}
364 	sc->sc_mii = device_get_softc(sc->sc_miibus);
365 
366 	/*
367 	 * From this point forward, the attachment cannot fail.  A failure
368 	 * before this point releases all resources that may have been
369 	 * allocated.
370 	 */
371 
372 	/* Get RX FIFO size. */
373 	sc->sc_rxfifosize = 64 *
374 	    GEM_BANK1_READ_4(sc, GEM_RX_FIFO_SIZE);
375 
376 	/* Get TX FIFO size. */
377 	v = GEM_BANK1_READ_4(sc, GEM_TX_FIFO_SIZE);
378 	device_printf(sc->sc_dev, "%ukB RX FIFO, %ukB TX FIFO\n",
379 	    sc->sc_rxfifosize / 1024, v / 16);
380 
381 	/* Attach the interface. */
382 	ether_ifattach(ifp, sc->sc_enaddr);
383 
384 	/*
385 	 * Tell the upper layer(s) we support long frames/checksum offloads.
386 	 */
387 	ifp->if_hdrlen = sizeof(struct ether_vlan_header);
388 	ifp->if_capabilities |= IFCAP_VLAN_MTU | IFCAP_HWCSUM;
389 	ifp->if_hwassist |= sc->sc_csum_features;
390 	ifp->if_capenable |= IFCAP_VLAN_MTU | IFCAP_HWCSUM;
391 
392 	return (0);
393 
394 	/*
395 	 * Free any resources we've allocated during the failed attach
396 	 * attempt.  Do this in reverse order and fall through.
397 	 */
398  fail_rxd:
399 	for (i = 0; i < GEM_NRXDESC; i++)
400 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
401 			bus_dmamap_destroy(sc->sc_rdmatag,
402 			    sc->sc_rxsoft[i].rxs_dmamap);
403  fail_txd:
404 	for (i = 0; i < GEM_TXQUEUELEN; i++)
405 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
406 			bus_dmamap_destroy(sc->sc_tdmatag,
407 			    sc->sc_txsoft[i].txs_dmamap);
408 	bus_dmamap_unload(sc->sc_cdmatag, sc->sc_cddmamap);
409  fail_cmem:
410 	bus_dmamem_free(sc->sc_cdmatag, sc->sc_control_data,
411 	    sc->sc_cddmamap);
412  fail_ctag:
413 	bus_dma_tag_destroy(sc->sc_cdmatag);
414  fail_ttag:
415 	bus_dma_tag_destroy(sc->sc_tdmatag);
416  fail_rtag:
417 	bus_dma_tag_destroy(sc->sc_rdmatag);
418  fail_ptag:
419 	bus_dma_tag_destroy(sc->sc_pdmatag);
420  fail_ifnet:
421 	if_free(ifp);
422 	return (error);
423 }
424 
425 void
426 gem_detach(struct gem_softc *sc)
427 {
428 	struct ifnet *ifp = sc->sc_ifp;
429 	int i;
430 
431 	ether_ifdetach(ifp);
432 	GEM_LOCK(sc);
433 	gem_stop(ifp, 1);
434 	GEM_UNLOCK(sc);
435 	callout_drain(&sc->sc_tick_ch);
436 #ifdef GEM_RINT_TIMEOUT
437 	callout_drain(&sc->sc_rx_ch);
438 #endif
439 	if_free(ifp);
440 	device_delete_child(sc->sc_dev, sc->sc_miibus);
441 
442 	for (i = 0; i < GEM_NRXDESC; i++)
443 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
444 			bus_dmamap_destroy(sc->sc_rdmatag,
445 			    sc->sc_rxsoft[i].rxs_dmamap);
446 	for (i = 0; i < GEM_TXQUEUELEN; i++)
447 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
448 			bus_dmamap_destroy(sc->sc_tdmatag,
449 			    sc->sc_txsoft[i].txs_dmamap);
450 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
451 	bus_dmamap_unload(sc->sc_cdmatag, sc->sc_cddmamap);
452 	bus_dmamem_free(sc->sc_cdmatag, sc->sc_control_data,
453 	    sc->sc_cddmamap);
454 	bus_dma_tag_destroy(sc->sc_cdmatag);
455 	bus_dma_tag_destroy(sc->sc_tdmatag);
456 	bus_dma_tag_destroy(sc->sc_rdmatag);
457 	bus_dma_tag_destroy(sc->sc_pdmatag);
458 }
459 
460 void
461 gem_suspend(struct gem_softc *sc)
462 {
463 	struct ifnet *ifp = sc->sc_ifp;
464 
465 	GEM_LOCK(sc);
466 	gem_stop(ifp, 0);
467 	GEM_UNLOCK(sc);
468 }
469 
470 void
471 gem_resume(struct gem_softc *sc)
472 {
473 	struct ifnet *ifp = sc->sc_ifp;
474 
475 	GEM_LOCK(sc);
476 	/*
477 	 * On resume all registers have to be initialized again like
478 	 * after power-on.
479 	 */
480 	sc->sc_flags &= ~GEM_INITED;
481 	if (ifp->if_flags & IFF_UP)
482 		gem_init_locked(sc);
483 	GEM_UNLOCK(sc);
484 }
485 
486 static inline void
487 gem_rxcksum(struct mbuf *m, uint64_t flags)
488 {
489 	struct ether_header *eh;
490 	struct ip *ip;
491 	struct udphdr *uh;
492 	uint16_t *opts;
493 	int32_t hlen, len, pktlen;
494 	uint32_t temp32;
495 	uint16_t cksum;
496 
497 	pktlen = m->m_pkthdr.len;
498 	if (pktlen < sizeof(struct ether_header) + sizeof(struct ip))
499 		return;
500 	eh = mtod(m, struct ether_header *);
501 	if (eh->ether_type != htons(ETHERTYPE_IP))
502 		return;
503 	ip = (struct ip *)(eh + 1);
504 	if (ip->ip_v != IPVERSION)
505 		return;
506 
507 	hlen = ip->ip_hl << 2;
508 	pktlen -= sizeof(struct ether_header);
509 	if (hlen < sizeof(struct ip))
510 		return;
511 	if (ntohs(ip->ip_len) < hlen)
512 		return;
513 	if (ntohs(ip->ip_len) != pktlen)
514 		return;
515 	if (ip->ip_off & htons(IP_MF | IP_OFFMASK))
516 		return;	/* Cannot handle fragmented packet. */
517 
518 	switch (ip->ip_p) {
519 	case IPPROTO_TCP:
520 		if (pktlen < (hlen + sizeof(struct tcphdr)))
521 			return;
522 		break;
523 	case IPPROTO_UDP:
524 		if (pktlen < (hlen + sizeof(struct udphdr)))
525 			return;
526 		uh = (struct udphdr *)((uint8_t *)ip + hlen);
527 		if (uh->uh_sum == 0)
528 			return; /* no checksum */
529 		break;
530 	default:
531 		return;
532 	}
533 
534 	cksum = ~(flags & GEM_RD_CHECKSUM);
535 	/* checksum fixup for IP options */
536 	len = hlen - sizeof(struct ip);
537 	if (len > 0) {
538 		opts = (uint16_t *)(ip + 1);
539 		for (; len > 0; len -= sizeof(uint16_t), opts++) {
540 			temp32 = cksum - *opts;
541 			temp32 = (temp32 >> 16) + (temp32 & 65535);
542 			cksum = temp32 & 65535;
543 		}
544 	}
545 	m->m_pkthdr.csum_flags |= CSUM_DATA_VALID;
546 	m->m_pkthdr.csum_data = cksum;
547 }
548 
549 static void
550 gem_cddma_callback(void *xsc, bus_dma_segment_t *segs, int nsegs, int error)
551 {
552 	struct gem_softc *sc = xsc;
553 
554 	if (error != 0)
555 		return;
556 	if (nsegs != 1)
557 		panic("%s: bad control buffer segment count", __func__);
558 	sc->sc_cddma = segs[0].ds_addr;
559 }
560 
561 static void
562 gem_tick(void *arg)
563 {
564 	struct gem_softc *sc = arg;
565 	struct ifnet *ifp = sc->sc_ifp;
566 	uint32_t v;
567 
568 	GEM_LOCK_ASSERT(sc, MA_OWNED);
569 
570 	/*
571 	 * Unload collision and error counters.
572 	 */
573 	if_inc_counter(ifp, IFCOUNTER_COLLISIONS,
574 	    GEM_BANK1_READ_4(sc, GEM_MAC_NORM_COLL_CNT) +
575 	    GEM_BANK1_READ_4(sc, GEM_MAC_FIRST_COLL_CNT));
576 	v = GEM_BANK1_READ_4(sc, GEM_MAC_EXCESS_COLL_CNT) +
577 	    GEM_BANK1_READ_4(sc, GEM_MAC_LATE_COLL_CNT);
578 	if_inc_counter(ifp, IFCOUNTER_COLLISIONS, v);
579 	if_inc_counter(ifp, IFCOUNTER_OERRORS, v);
580 	if_inc_counter(ifp, IFCOUNTER_IERRORS,
581 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_LEN_ERR_CNT) +
582 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_ALIGN_ERR) +
583 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CRC_ERR_CNT) +
584 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CODE_VIOL));
585 
586 	/*
587 	 * Then clear the hardware counters.
588 	 */
589 	GEM_BANK1_WRITE_4(sc, GEM_MAC_NORM_COLL_CNT, 0);
590 	GEM_BANK1_WRITE_4(sc, GEM_MAC_FIRST_COLL_CNT, 0);
591 	GEM_BANK1_WRITE_4(sc, GEM_MAC_EXCESS_COLL_CNT, 0);
592 	GEM_BANK1_WRITE_4(sc, GEM_MAC_LATE_COLL_CNT, 0);
593 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_LEN_ERR_CNT, 0);
594 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_ALIGN_ERR, 0);
595 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CRC_ERR_CNT, 0);
596 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CODE_VIOL, 0);
597 
598 	mii_tick(sc->sc_mii);
599 
600 	if (gem_watchdog(sc) == EJUSTRETURN)
601 		return;
602 
603 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
604 }
605 
606 static int
607 gem_bitwait(struct gem_softc *sc, u_int bank, bus_addr_t r, uint32_t clr,
608     uint32_t set)
609 {
610 	int i;
611 	uint32_t reg;
612 
613 	for (i = GEM_TRIES; i--; DELAY(100)) {
614 		reg = GEM_BANKN_READ_M(bank, 4, sc, r);
615 		if ((reg & clr) == 0 && (reg & set) == set)
616 			return (1);
617 	}
618 	return (0);
619 }
620 
621 static void
622 gem_reset(struct gem_softc *sc)
623 {
624 
625 #ifdef GEM_DEBUG
626 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
627 #endif
628 	gem_reset_rx(sc);
629 	gem_reset_tx(sc);
630 
631 	/* Do a full reset. */
632 	GEM_BANK2_WRITE_4(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX |
633 	    (sc->sc_variant == GEM_SUN_ERI ? GEM_ERI_CACHE_LINE_SIZE <<
634 	    GEM_RESET_CLSZ_SHFT : 0));
635 	GEM_BANK2_BARRIER(sc, GEM_RESET, 4,
636 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
637 	if (!GEM_BANK2_BITWAIT(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX, 0))
638 		device_printf(sc->sc_dev, "cannot reset device\n");
639 }
640 
641 static void
642 gem_rxdrain(struct gem_softc *sc)
643 {
644 	struct gem_rxsoft *rxs;
645 	int i;
646 
647 	for (i = 0; i < GEM_NRXDESC; i++) {
648 		rxs = &sc->sc_rxsoft[i];
649 		if (rxs->rxs_mbuf != NULL) {
650 			bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
651 			    BUS_DMASYNC_POSTREAD);
652 			bus_dmamap_unload(sc->sc_rdmatag, rxs->rxs_dmamap);
653 			m_freem(rxs->rxs_mbuf);
654 			rxs->rxs_mbuf = NULL;
655 		}
656 	}
657 }
658 
659 static void
660 gem_stop(struct ifnet *ifp, int disable)
661 {
662 	struct gem_softc *sc = ifp->if_softc;
663 	struct gem_txsoft *txs;
664 
665 #ifdef GEM_DEBUG
666 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
667 #endif
668 
669 	callout_stop(&sc->sc_tick_ch);
670 #ifdef GEM_RINT_TIMEOUT
671 	callout_stop(&sc->sc_rx_ch);
672 #endif
673 
674 	gem_reset_tx(sc);
675 	gem_reset_rx(sc);
676 
677 	/*
678 	 * Release any queued transmit buffers.
679 	 */
680 	while ((txs = STAILQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
681 		STAILQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
682 		if (txs->txs_ndescs != 0) {
683 			bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
684 			    BUS_DMASYNC_POSTWRITE);
685 			bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
686 			if (txs->txs_mbuf != NULL) {
687 				m_freem(txs->txs_mbuf);
688 				txs->txs_mbuf = NULL;
689 			}
690 		}
691 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
692 	}
693 
694 	if (disable)
695 		gem_rxdrain(sc);
696 
697 	/*
698 	 * Mark the interface down and cancel the watchdog timer.
699 	 */
700 	ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
701 	sc->sc_flags &= ~GEM_LINK;
702 	sc->sc_wdog_timer = 0;
703 }
704 
705 static int
706 gem_reset_rx(struct gem_softc *sc)
707 {
708 
709 	/*
710 	 * Resetting while DMA is in progress can cause a bus hang, so we
711 	 * disable DMA first.
712 	 */
713 	(void)gem_disable_rx(sc);
714 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG, 0);
715 	GEM_BANK1_BARRIER(sc, GEM_RX_CONFIG, 4,
716 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
717 	if (!GEM_BANK1_BITWAIT(sc, GEM_RX_CONFIG, GEM_RX_CONFIG_RXDMA_EN, 0))
718 		device_printf(sc->sc_dev, "cannot disable RX DMA\n");
719 
720 	/* Wait 5ms extra. */
721 	DELAY(5000);
722 
723 	/* Reset the ERX. */
724 	GEM_BANK2_WRITE_4(sc, GEM_RESET, GEM_RESET_RX |
725 	    (sc->sc_variant == GEM_SUN_ERI ? GEM_ERI_CACHE_LINE_SIZE <<
726 	    GEM_RESET_CLSZ_SHFT : 0));
727 	GEM_BANK2_BARRIER(sc, GEM_RESET, 4,
728 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
729 	if (!GEM_BANK2_BITWAIT(sc, GEM_RESET, GEM_RESET_RX, 0)) {
730 		device_printf(sc->sc_dev, "cannot reset receiver\n");
731 		return (1);
732 	}
733 
734 	/* Finally, reset RX MAC. */
735 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RXRESET, 1);
736 	GEM_BANK1_BARRIER(sc, GEM_MAC_RXRESET, 4,
737 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
738 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_RXRESET, 1, 0)) {
739 		device_printf(sc->sc_dev, "cannot reset RX MAC\n");
740 		return (1);
741 	}
742 
743 	return (0);
744 }
745 
746 /*
747  * Reset the receiver DMA engine.
748  *
749  * Intended to be used in case of GEM_INTR_RX_TAG_ERR, GEM_MAC_RX_OVERFLOW
750  * etc in order to reset the receiver DMA engine only and not do a full
751  * reset which amongst others also downs the link and clears the FIFOs.
752  */
753 static void
754 gem_reset_rxdma(struct gem_softc *sc)
755 {
756 	int i;
757 
758 	if (gem_reset_rx(sc) != 0) {
759 		sc->sc_ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
760 		return (gem_init_locked(sc));
761 	}
762 	for (i = 0; i < GEM_NRXDESC; i++)
763 		if (sc->sc_rxsoft[i].rxs_mbuf != NULL)
764 			GEM_UPDATE_RXDESC(sc, i);
765 	sc->sc_rxptr = 0;
766 	GEM_CDSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
767 
768 	/* NOTE: we use only 32-bit DMA addresses here. */
769 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_HI, 0);
770 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_LO, GEM_CDRXADDR(sc, 0));
771 	GEM_BANK1_WRITE_4(sc, GEM_RX_KICK, GEM_NRXDESC - 4);
772 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG,
773 	    gem_ringsize(GEM_NRXDESC /* XXX */) |
774 	    ((ETHER_HDR_LEN + sizeof(struct ip)) <<
775 	    GEM_RX_CONFIG_CXM_START_SHFT) |
776 	    (GEM_THRSH_1024 << GEM_RX_CONFIG_FIFO_THRS_SHIFT) |
777 	    (ETHER_ALIGN << GEM_RX_CONFIG_FBOFF_SHFT));
778 	/* Adjusting for the SBus clock probably isn't worth the fuzz. */
779 	GEM_BANK1_WRITE_4(sc, GEM_RX_BLANKING,
780 	    ((6 * (sc->sc_flags & GEM_PCI66) != 0 ? 2 : 1) <<
781 	    GEM_RX_BLANKING_TIME_SHIFT) | 6);
782 	GEM_BANK1_WRITE_4(sc, GEM_RX_PAUSE_THRESH,
783 	    (3 * sc->sc_rxfifosize / 256) |
784 	    ((sc->sc_rxfifosize / 256) << 12));
785 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG,
786 	    GEM_BANK1_READ_4(sc, GEM_RX_CONFIG) | GEM_RX_CONFIG_RXDMA_EN);
787 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_MASK,
788 	    GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT);
789 	/*
790 	 * Clear the RX filter and reprogram it.  This will also set the
791 	 * current RX MAC configuration and enable it.
792 	 */
793 	gem_setladrf(sc);
794 }
795 
796 static int
797 gem_reset_tx(struct gem_softc *sc)
798 {
799 
800 	/*
801 	 * Resetting while DMA is in progress can cause a bus hang, so we
802 	 * disable DMA first.
803 	 */
804 	(void)gem_disable_tx(sc);
805 	GEM_BANK1_WRITE_4(sc, GEM_TX_CONFIG, 0);
806 	GEM_BANK1_BARRIER(sc, GEM_TX_CONFIG, 4,
807 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
808 	if (!GEM_BANK1_BITWAIT(sc, GEM_TX_CONFIG, GEM_TX_CONFIG_TXDMA_EN, 0))
809 		device_printf(sc->sc_dev, "cannot disable TX DMA\n");
810 
811 	/* Wait 5ms extra. */
812 	DELAY(5000);
813 
814 	/* Finally, reset the ETX. */
815 	GEM_BANK2_WRITE_4(sc, GEM_RESET, GEM_RESET_TX |
816 	    (sc->sc_variant == GEM_SUN_ERI ? GEM_ERI_CACHE_LINE_SIZE <<
817 	    GEM_RESET_CLSZ_SHFT : 0));
818 	GEM_BANK2_BARRIER(sc, GEM_RESET, 4,
819 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
820 	if (!GEM_BANK2_BITWAIT(sc, GEM_RESET, GEM_RESET_TX, 0)) {
821 		device_printf(sc->sc_dev, "cannot reset transmitter\n");
822 		return (1);
823 	}
824 	return (0);
825 }
826 
827 static int
828 gem_disable_rx(struct gem_softc *sc)
829 {
830 
831 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG,
832 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG) & ~GEM_MAC_RX_ENABLE);
833 	GEM_BANK1_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
834 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
835 	if (GEM_BANK1_BITWAIT(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_ENABLE, 0))
836 		return (1);
837 	device_printf(sc->sc_dev, "cannot disable RX MAC\n");
838 	return (0);
839 }
840 
841 static int
842 gem_disable_tx(struct gem_softc *sc)
843 {
844 
845 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG,
846 	    GEM_BANK1_READ_4(sc, GEM_MAC_TX_CONFIG) & ~GEM_MAC_TX_ENABLE);
847 	GEM_BANK1_BARRIER(sc, GEM_MAC_TX_CONFIG, 4,
848 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
849 	if (GEM_BANK1_BITWAIT(sc, GEM_MAC_TX_CONFIG, GEM_MAC_TX_ENABLE, 0))
850 		return (1);
851 	device_printf(sc->sc_dev, "cannot disable TX MAC\n");
852 	return (0);
853 }
854 
855 static int
856 gem_meminit(struct gem_softc *sc)
857 {
858 	struct gem_rxsoft *rxs;
859 	int error, i;
860 
861 	GEM_LOCK_ASSERT(sc, MA_OWNED);
862 
863 	/*
864 	 * Initialize the transmit descriptor ring.
865 	 */
866 	for (i = 0; i < GEM_NTXDESC; i++) {
867 		sc->sc_txdescs[i].gd_flags = 0;
868 		sc->sc_txdescs[i].gd_addr = 0;
869 	}
870 	sc->sc_txfree = GEM_MAXTXFREE;
871 	sc->sc_txnext = 0;
872 	sc->sc_txwin = 0;
873 
874 	/*
875 	 * Initialize the receive descriptor and receive job
876 	 * descriptor rings.
877 	 */
878 	for (i = 0; i < GEM_NRXDESC; i++) {
879 		rxs = &sc->sc_rxsoft[i];
880 		if (rxs->rxs_mbuf == NULL) {
881 			if ((error = gem_add_rxbuf(sc, i)) != 0) {
882 				device_printf(sc->sc_dev,
883 				    "unable to allocate or map RX buffer %d, "
884 				    "error = %d\n", i, error);
885 				/*
886 				 * XXX we should attempt to run with fewer
887 				 * receive buffers instead of just failing.
888 				 */
889 				gem_rxdrain(sc);
890 				return (1);
891 			}
892 		} else
893 			GEM_INIT_RXDESC(sc, i);
894 	}
895 	sc->sc_rxptr = 0;
896 
897 	GEM_CDSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
898 
899 	return (0);
900 }
901 
902 static u_int
903 gem_ringsize(u_int sz)
904 {
905 
906 	switch (sz) {
907 	case 32:
908 		return (GEM_RING_SZ_32);
909 	case 64:
910 		return (GEM_RING_SZ_64);
911 	case 128:
912 		return (GEM_RING_SZ_128);
913 	case 256:
914 		return (GEM_RING_SZ_256);
915 	case 512:
916 		return (GEM_RING_SZ_512);
917 	case 1024:
918 		return (GEM_RING_SZ_1024);
919 	case 2048:
920 		return (GEM_RING_SZ_2048);
921 	case 4096:
922 		return (GEM_RING_SZ_4096);
923 	case 8192:
924 		return (GEM_RING_SZ_8192);
925 	default:
926 		printf("%s: invalid ring size %d\n", __func__, sz);
927 		return (GEM_RING_SZ_32);
928 	}
929 }
930 
931 static void
932 gem_init(void *xsc)
933 {
934 	struct gem_softc *sc = xsc;
935 
936 	GEM_LOCK(sc);
937 	gem_init_locked(sc);
938 	GEM_UNLOCK(sc);
939 }
940 
941 /*
942  * Initialization of interface; set up initialization block
943  * and transmit/receive descriptor rings.
944  */
945 static void
946 gem_init_locked(struct gem_softc *sc)
947 {
948 	struct ifnet *ifp = sc->sc_ifp;
949 	uint32_t v;
950 
951 	GEM_LOCK_ASSERT(sc, MA_OWNED);
952 
953 	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
954 		return;
955 
956 #ifdef GEM_DEBUG
957 	CTR2(KTR_GEM, "%s: %s: calling stop", device_get_name(sc->sc_dev),
958 	    __func__);
959 #endif
960 	/*
961 	 * Initialization sequence.  The numbered steps below correspond
962 	 * to the sequence outlined in section 6.3.5.1 in the Ethernet
963 	 * Channel Engine manual (part of the PCIO manual).
964 	 * See also the STP2002-STQ document from Sun Microsystems.
965 	 */
966 
967 	/* step 1 & 2.  Reset the Ethernet Channel. */
968 	gem_stop(ifp, 0);
969 	gem_reset(sc);
970 #ifdef GEM_DEBUG
971 	CTR2(KTR_GEM, "%s: %s: restarting", device_get_name(sc->sc_dev),
972 	    __func__);
973 #endif
974 
975 	if ((sc->sc_flags & GEM_SERDES) == 0)
976 		/* Re-initialize the MIF. */
977 		gem_mifinit(sc);
978 
979 	/* step 3.  Setup data structures in host memory. */
980 	if (gem_meminit(sc) != 0)
981 		return;
982 
983 	/* step 4.  TX MAC registers & counters */
984 	gem_init_regs(sc);
985 
986 	/* step 5.  RX MAC registers & counters */
987 
988 	/* step 6 & 7.  Program Descriptor Ring Base Addresses. */
989 	/* NOTE: we use only 32-bit DMA addresses here. */
990 	GEM_BANK1_WRITE_4(sc, GEM_TX_RING_PTR_HI, 0);
991 	GEM_BANK1_WRITE_4(sc, GEM_TX_RING_PTR_LO, GEM_CDTXADDR(sc, 0));
992 
993 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_HI, 0);
994 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_LO, GEM_CDRXADDR(sc, 0));
995 #ifdef GEM_DEBUG
996 	CTR3(KTR_GEM, "loading RX ring %lx, TX ring %lx, cddma %lx",
997 	    GEM_CDRXADDR(sc, 0), GEM_CDTXADDR(sc, 0), sc->sc_cddma);
998 #endif
999 
1000 	/* step 8.  Global Configuration & Interrupt Mask */
1001 
1002 	/*
1003 	 * Set the internal arbitration to "infinite" bursts of the
1004 	 * maximum length of 31 * 64 bytes so DMA transfers aren't
1005 	 * split up in cache line size chunks.  This greatly improves
1006 	 * RX performance.
1007 	 * Enable silicon bug workarounds for the Apple variants.
1008 	 */
1009 	GEM_BANK1_WRITE_4(sc, GEM_CONFIG,
1010 	    GEM_CONFIG_TXDMA_LIMIT | GEM_CONFIG_RXDMA_LIMIT |
1011 	    ((sc->sc_flags & GEM_PCI) != 0 ? GEM_CONFIG_BURST_INF :
1012 	    GEM_CONFIG_BURST_64) | (GEM_IS_APPLE(sc) ?
1013 	    GEM_CONFIG_RONPAULBIT | GEM_CONFIG_BUG2FIX : 0));
1014 
1015 	GEM_BANK1_WRITE_4(sc, GEM_INTMASK,
1016 	    ~(GEM_INTR_TX_INTME | GEM_INTR_TX_EMPTY | GEM_INTR_RX_DONE |
1017 	    GEM_INTR_RX_NOBUF | GEM_INTR_RX_TAG_ERR | GEM_INTR_PERR |
1018 	    GEM_INTR_BERR
1019 #ifdef GEM_DEBUG
1020 	    | GEM_INTR_PCS | GEM_INTR_MIF
1021 #endif
1022 	    ));
1023 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_MASK,
1024 	    GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT);
1025 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_MASK,
1026 	    GEM_MAC_TX_XMIT_DONE | GEM_MAC_TX_DEFER_EXP |
1027 	    GEM_MAC_TX_PEAK_EXP);
1028 #ifdef GEM_DEBUG
1029 	GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_MASK,
1030 	    ~(GEM_MAC_PAUSED | GEM_MAC_PAUSE | GEM_MAC_RESUME));
1031 #else
1032 	GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_MASK,
1033 	    GEM_MAC_PAUSED | GEM_MAC_PAUSE | GEM_MAC_RESUME);
1034 #endif
1035 
1036 	/* step 9.  ETX Configuration: use mostly default values. */
1037 
1038 	/* Enable DMA. */
1039 	v = gem_ringsize(GEM_NTXDESC);
1040 	/* Set TX FIFO threshold and enable DMA. */
1041 	v |= ((sc->sc_variant == GEM_SUN_ERI ? 0x100 : 0x4ff) << 10) &
1042 	    GEM_TX_CONFIG_TXFIFO_TH;
1043 	GEM_BANK1_WRITE_4(sc, GEM_TX_CONFIG, v | GEM_TX_CONFIG_TXDMA_EN);
1044 
1045 	/* step 10.  ERX Configuration */
1046 
1047 	/* Encode Receive Descriptor ring size. */
1048 	v = gem_ringsize(GEM_NRXDESC /* XXX */);
1049 	/* RX TCP/UDP checksum offset */
1050 	v |= ((ETHER_HDR_LEN + sizeof(struct ip)) <<
1051 	    GEM_RX_CONFIG_CXM_START_SHFT);
1052 	/* Set RX FIFO threshold, set first byte offset and enable DMA. */
1053 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG,
1054 	    v | (GEM_THRSH_1024 << GEM_RX_CONFIG_FIFO_THRS_SHIFT) |
1055 	    (ETHER_ALIGN << GEM_RX_CONFIG_FBOFF_SHFT) |
1056 	    GEM_RX_CONFIG_RXDMA_EN);
1057 
1058 	/* Adjusting for the SBus clock probably isn't worth the fuzz. */
1059 	GEM_BANK1_WRITE_4(sc, GEM_RX_BLANKING,
1060 	    ((6 * (sc->sc_flags & GEM_PCI66) != 0 ? 2 : 1) <<
1061 	    GEM_RX_BLANKING_TIME_SHIFT) | 6);
1062 
1063 	/*
1064 	 * The following value is for an OFF Threshold of about 3/4 full
1065 	 * and an ON Threshold of 1/4 full.
1066 	 */
1067 	GEM_BANK1_WRITE_4(sc, GEM_RX_PAUSE_THRESH,
1068 	    (3 * sc->sc_rxfifosize / 256) |
1069 	    ((sc->sc_rxfifosize / 256) << 12));
1070 
1071 	/* step 11.  Configure Media. */
1072 
1073 	/* step 12.  RX_MAC Configuration Register */
1074 	v = GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG);
1075 	v &= ~GEM_MAC_RX_ENABLE;
1076 	v |= GEM_MAC_RX_STRIP_CRC;
1077 	sc->sc_mac_rxcfg = v;
1078 	/*
1079 	 * Clear the RX filter and reprogram it.  This will also set the
1080 	 * current RX MAC configuration and enable it.
1081 	 */
1082 	gem_setladrf(sc);
1083 
1084 	/* step 13.  TX_MAC Configuration Register */
1085 	v = GEM_BANK1_READ_4(sc, GEM_MAC_TX_CONFIG);
1086 	v |= GEM_MAC_TX_ENABLE;
1087 	(void)gem_disable_tx(sc);
1088 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG, v);
1089 
1090 	/* step 14.  Issue Transmit Pending command. */
1091 
1092 	/* step 15.  Give the receiver a swift kick. */
1093 	GEM_BANK1_WRITE_4(sc, GEM_RX_KICK, GEM_NRXDESC - 4);
1094 
1095 	ifp->if_drv_flags |= IFF_DRV_RUNNING;
1096 	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
1097 
1098 	mii_mediachg(sc->sc_mii);
1099 
1100 	/* Start the one second timer. */
1101 	sc->sc_wdog_timer = 0;
1102 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
1103 }
1104 
1105 static int
1106 gem_load_txmbuf(struct gem_softc *sc, struct mbuf **m_head)
1107 {
1108 	bus_dma_segment_t txsegs[GEM_NTXSEGS];
1109 	struct gem_txsoft *txs;
1110 	struct ip *ip;
1111 	struct mbuf *m;
1112 	uint64_t cflags, flags;
1113 	int error, nexttx, nsegs, offset, seg;
1114 
1115 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1116 
1117 	/* Get a work queue entry. */
1118 	if ((txs = STAILQ_FIRST(&sc->sc_txfreeq)) == NULL) {
1119 		/* Ran out of descriptors. */
1120 		return (ENOBUFS);
1121 	}
1122 
1123 	cflags = 0;
1124 	if (((*m_head)->m_pkthdr.csum_flags & sc->sc_csum_features) != 0) {
1125 		if (M_WRITABLE(*m_head) == 0) {
1126 			m = m_dup(*m_head, M_NOWAIT);
1127 			m_freem(*m_head);
1128 			*m_head = m;
1129 			if (m == NULL)
1130 				return (ENOBUFS);
1131 		}
1132 		offset = sizeof(struct ether_header);
1133 		m = m_pullup(*m_head, offset + sizeof(struct ip));
1134 		if (m == NULL) {
1135 			*m_head = NULL;
1136 			return (ENOBUFS);
1137 		}
1138 		ip = (struct ip *)(mtod(m, caddr_t) + offset);
1139 		offset += (ip->ip_hl << 2);
1140 		cflags = offset << GEM_TD_CXSUM_STARTSHFT |
1141 		    ((offset + m->m_pkthdr.csum_data) <<
1142 		    GEM_TD_CXSUM_STUFFSHFT) | GEM_TD_CXSUM_ENABLE;
1143 		*m_head = m;
1144 	}
1145 
1146 	error = bus_dmamap_load_mbuf_sg(sc->sc_tdmatag, txs->txs_dmamap,
1147 	    *m_head, txsegs, &nsegs, BUS_DMA_NOWAIT);
1148 	if (error == EFBIG) {
1149 		m = m_collapse(*m_head, M_NOWAIT, GEM_NTXSEGS);
1150 		if (m == NULL) {
1151 			m_freem(*m_head);
1152 			*m_head = NULL;
1153 			return (ENOBUFS);
1154 		}
1155 		*m_head = m;
1156 		error = bus_dmamap_load_mbuf_sg(sc->sc_tdmatag,
1157 		    txs->txs_dmamap, *m_head, txsegs, &nsegs,
1158 		    BUS_DMA_NOWAIT);
1159 		if (error != 0) {
1160 			m_freem(*m_head);
1161 			*m_head = NULL;
1162 			return (error);
1163 		}
1164 	} else if (error != 0)
1165 		return (error);
1166 	/* If nsegs is wrong then the stack is corrupt. */
1167 	KASSERT(nsegs <= GEM_NTXSEGS,
1168 	    ("%s: too many DMA segments (%d)", __func__, nsegs));
1169 	if (nsegs == 0) {
1170 		m_freem(*m_head);
1171 		*m_head = NULL;
1172 		return (EIO);
1173 	}
1174 
1175 	/*
1176 	 * Ensure we have enough descriptors free to describe
1177 	 * the packet.  Note, we always reserve one descriptor
1178 	 * at the end of the ring as a termination point, in
1179 	 * order to prevent wrap-around.
1180 	 */
1181 	if (nsegs > sc->sc_txfree - 1) {
1182 		txs->txs_ndescs = 0;
1183 		bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
1184 		return (ENOBUFS);
1185 	}
1186 
1187 	txs->txs_ndescs = nsegs;
1188 	txs->txs_firstdesc = sc->sc_txnext;
1189 	nexttx = txs->txs_firstdesc;
1190 	for (seg = 0; seg < nsegs; seg++, nexttx = GEM_NEXTTX(nexttx)) {
1191 #ifdef GEM_DEBUG
1192 		CTR6(KTR_GEM,
1193 		    "%s: mapping seg %d (txd %d), len %lx, addr %#lx (%#lx)",
1194 		    __func__, seg, nexttx, txsegs[seg].ds_len,
1195 		    txsegs[seg].ds_addr,
1196 		    GEM_DMA_WRITE(sc, txsegs[seg].ds_addr));
1197 #endif
1198 		sc->sc_txdescs[nexttx].gd_addr =
1199 		    GEM_DMA_WRITE(sc, txsegs[seg].ds_addr);
1200 		KASSERT(txsegs[seg].ds_len < GEM_TD_BUFSIZE,
1201 		    ("%s: segment size too large!", __func__));
1202 		flags = txsegs[seg].ds_len & GEM_TD_BUFSIZE;
1203 		sc->sc_txdescs[nexttx].gd_flags =
1204 		    GEM_DMA_WRITE(sc, flags | cflags);
1205 		txs->txs_lastdesc = nexttx;
1206 	}
1207 
1208 	/* Set EOP on the last descriptor. */
1209 #ifdef GEM_DEBUG
1210 	CTR3(KTR_GEM, "%s: end of packet at segment %d, TX %d",
1211 	    __func__, seg, nexttx);
1212 #endif
1213 	sc->sc_txdescs[txs->txs_lastdesc].gd_flags |=
1214 	    GEM_DMA_WRITE(sc, GEM_TD_END_OF_PACKET);
1215 
1216 	/* Lastly set SOP on the first descriptor. */
1217 #ifdef GEM_DEBUG
1218 	CTR3(KTR_GEM, "%s: start of packet at segment %d, TX %d",
1219 	    __func__, seg, nexttx);
1220 #endif
1221 	if (++sc->sc_txwin > GEM_NTXSEGS * 2 / 3) {
1222 		sc->sc_txwin = 0;
1223 		sc->sc_txdescs[txs->txs_firstdesc].gd_flags |=
1224 		    GEM_DMA_WRITE(sc, GEM_TD_INTERRUPT_ME |
1225 		    GEM_TD_START_OF_PACKET);
1226 	} else
1227 		sc->sc_txdescs[txs->txs_firstdesc].gd_flags |=
1228 		    GEM_DMA_WRITE(sc, GEM_TD_START_OF_PACKET);
1229 
1230 	/* Sync the DMA map. */
1231 	bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
1232 	    BUS_DMASYNC_PREWRITE);
1233 
1234 #ifdef GEM_DEBUG
1235 	CTR4(KTR_GEM, "%s: setting firstdesc=%d, lastdesc=%d, ndescs=%d",
1236 	    __func__, txs->txs_firstdesc, txs->txs_lastdesc,
1237 	    txs->txs_ndescs);
1238 #endif
1239 	STAILQ_REMOVE_HEAD(&sc->sc_txfreeq, txs_q);
1240 	STAILQ_INSERT_TAIL(&sc->sc_txdirtyq, txs, txs_q);
1241 	txs->txs_mbuf = *m_head;
1242 
1243 	sc->sc_txnext = GEM_NEXTTX(txs->txs_lastdesc);
1244 	sc->sc_txfree -= txs->txs_ndescs;
1245 
1246 	return (0);
1247 }
1248 
1249 static void
1250 gem_init_regs(struct gem_softc *sc)
1251 {
1252 	const u_char *laddr = IF_LLADDR(sc->sc_ifp);
1253 
1254 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1255 
1256 	/* These registers are not cleared on reset. */
1257 	if ((sc->sc_flags & GEM_INITED) == 0) {
1258 		/* magic values */
1259 		GEM_BANK1_WRITE_4(sc, GEM_MAC_IPG0, 0);
1260 		GEM_BANK1_WRITE_4(sc, GEM_MAC_IPG1, 8);
1261 		GEM_BANK1_WRITE_4(sc, GEM_MAC_IPG2, 4);
1262 
1263 		/* min frame length */
1264 		GEM_BANK1_WRITE_4(sc, GEM_MAC_MAC_MIN_FRAME, ETHER_MIN_LEN);
1265 		/* max frame length and max burst size */
1266 		GEM_BANK1_WRITE_4(sc, GEM_MAC_MAC_MAX_FRAME,
1267 		    (ETHER_MAX_LEN + ETHER_VLAN_ENCAP_LEN) | (0x2000 << 16));
1268 
1269 		/* more magic values */
1270 		GEM_BANK1_WRITE_4(sc, GEM_MAC_PREAMBLE_LEN, 0x7);
1271 		GEM_BANK1_WRITE_4(sc, GEM_MAC_JAM_SIZE, 0x4);
1272 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ATTEMPT_LIMIT, 0x10);
1273 		GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_TYPE, 0x8808);
1274 
1275 		/* random number seed */
1276 		GEM_BANK1_WRITE_4(sc, GEM_MAC_RANDOM_SEED,
1277 		    ((laddr[5] << 8) | laddr[4]) & 0x3ff);
1278 
1279 		/* secondary MAC address: 0:0:0:0:0:0 */
1280 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR3, 0);
1281 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR4, 0);
1282 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR5, 0);
1283 
1284 		/* MAC control address: 01:80:c2:00:00:01 */
1285 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR6, 0x0001);
1286 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR7, 0xc200);
1287 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR8, 0x0180);
1288 
1289 		/* MAC filter address: 0:0:0:0:0:0 */
1290 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR_FILTER0, 0);
1291 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR_FILTER1, 0);
1292 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR_FILTER2, 0);
1293 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADR_FLT_MASK1_2, 0);
1294 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADR_FLT_MASK0, 0);
1295 
1296 		sc->sc_flags |= GEM_INITED;
1297 	}
1298 
1299 	/* Counters need to be zeroed. */
1300 	GEM_BANK1_WRITE_4(sc, GEM_MAC_NORM_COLL_CNT, 0);
1301 	GEM_BANK1_WRITE_4(sc, GEM_MAC_FIRST_COLL_CNT, 0);
1302 	GEM_BANK1_WRITE_4(sc, GEM_MAC_EXCESS_COLL_CNT, 0);
1303 	GEM_BANK1_WRITE_4(sc, GEM_MAC_LATE_COLL_CNT, 0);
1304 	GEM_BANK1_WRITE_4(sc, GEM_MAC_DEFER_TMR_CNT, 0);
1305 	GEM_BANK1_WRITE_4(sc, GEM_MAC_PEAK_ATTEMPTS, 0);
1306 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_FRAME_COUNT, 0);
1307 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_LEN_ERR_CNT, 0);
1308 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_ALIGN_ERR, 0);
1309 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CRC_ERR_CNT, 0);
1310 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CODE_VIOL, 0);
1311 
1312 	/* Set XOFF PAUSE time. */
1313 	GEM_BANK1_WRITE_4(sc, GEM_MAC_SEND_PAUSE_CMD, 0x1BF0);
1314 
1315 	/* Set the station address. */
1316 	GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR0, (laddr[4] << 8) | laddr[5]);
1317 	GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR1, (laddr[2] << 8) | laddr[3]);
1318 	GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR2, (laddr[0] << 8) | laddr[1]);
1319 
1320 	/* Enable MII outputs. */
1321 	GEM_BANK1_WRITE_4(sc, GEM_MAC_XIF_CONFIG, GEM_MAC_XIF_TX_MII_ENA);
1322 }
1323 
1324 static void
1325 gem_start(struct ifnet *ifp)
1326 {
1327 	struct gem_softc *sc = ifp->if_softc;
1328 
1329 	GEM_LOCK(sc);
1330 	gem_start_locked(ifp);
1331 	GEM_UNLOCK(sc);
1332 }
1333 
1334 static inline void
1335 gem_txkick(struct gem_softc *sc)
1336 {
1337 
1338 	/*
1339 	 * Update the TX kick register.  This register has to point to the
1340 	 * descriptor after the last valid one and for optimum performance
1341 	 * should be incremented in multiples of 4 (the DMA engine fetches/
1342 	 * updates descriptors in batches of 4).
1343 	 */
1344 #ifdef GEM_DEBUG
1345 	CTR3(KTR_GEM, "%s: %s: kicking TX %d",
1346 	    device_get_name(sc->sc_dev), __func__, sc->sc_txnext);
1347 #endif
1348 	GEM_CDSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1349 	GEM_BANK1_WRITE_4(sc, GEM_TX_KICK, sc->sc_txnext);
1350 }
1351 
1352 static void
1353 gem_start_locked(struct ifnet *ifp)
1354 {
1355 	struct gem_softc *sc = ifp->if_softc;
1356 	struct mbuf *m;
1357 	int kicked, ntx;
1358 
1359 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1360 
1361 	if ((ifp->if_drv_flags & (IFF_DRV_RUNNING | IFF_DRV_OACTIVE)) !=
1362 	    IFF_DRV_RUNNING || (sc->sc_flags & GEM_LINK) == 0)
1363 		return;
1364 
1365 #ifdef GEM_DEBUG
1366 	CTR4(KTR_GEM, "%s: %s: txfree %d, txnext %d",
1367 	    device_get_name(sc->sc_dev), __func__, sc->sc_txfree,
1368 	    sc->sc_txnext);
1369 #endif
1370 	ntx = 0;
1371 	kicked = 0;
1372 	for (; !IFQ_DRV_IS_EMPTY(&ifp->if_snd) && sc->sc_txfree > 1;) {
1373 		IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
1374 		if (m == NULL)
1375 			break;
1376 		if (gem_load_txmbuf(sc, &m) != 0) {
1377 			if (m == NULL)
1378 				break;
1379 			ifp->if_drv_flags |= IFF_DRV_OACTIVE;
1380 			IFQ_DRV_PREPEND(&ifp->if_snd, m);
1381 			break;
1382 		}
1383 		if ((sc->sc_txnext % 4) == 0) {
1384 			gem_txkick(sc);
1385 			kicked = 1;
1386 		} else
1387 			kicked = 0;
1388 		ntx++;
1389 		BPF_MTAP(ifp, m);
1390 	}
1391 
1392 	if (ntx > 0) {
1393 		if (kicked == 0)
1394 			gem_txkick(sc);
1395 #ifdef GEM_DEBUG
1396 		CTR2(KTR_GEM, "%s: packets enqueued, OWN on %d",
1397 		    device_get_name(sc->sc_dev), sc->sc_txnext);
1398 #endif
1399 
1400 		/* Set a watchdog timer in case the chip flakes out. */
1401 		sc->sc_wdog_timer = 5;
1402 #ifdef GEM_DEBUG
1403 		CTR3(KTR_GEM, "%s: %s: watchdog %d",
1404 		    device_get_name(sc->sc_dev), __func__,
1405 		    sc->sc_wdog_timer);
1406 #endif
1407 	}
1408 }
1409 
1410 static void
1411 gem_tint(struct gem_softc *sc)
1412 {
1413 	struct ifnet *ifp = sc->sc_ifp;
1414 	struct gem_txsoft *txs;
1415 	int progress;
1416 	uint32_t txlast;
1417 #ifdef GEM_DEBUG
1418 	int i;
1419 
1420 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1421 
1422 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
1423 #endif
1424 
1425 	/*
1426 	 * Go through our TX list and free mbufs for those
1427 	 * frames that have been transmitted.
1428 	 */
1429 	progress = 0;
1430 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD);
1431 	while ((txs = STAILQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
1432 #ifdef GEM_DEBUG
1433 		if ((ifp->if_flags & IFF_DEBUG) != 0) {
1434 			printf("    txsoft %p transmit chain:\n", txs);
1435 			for (i = txs->txs_firstdesc;; i = GEM_NEXTTX(i)) {
1436 				printf("descriptor %d: ", i);
1437 				printf("gd_flags: 0x%016llx\t",
1438 				    (long long)GEM_DMA_READ(sc,
1439 				    sc->sc_txdescs[i].gd_flags));
1440 				printf("gd_addr: 0x%016llx\n",
1441 				    (long long)GEM_DMA_READ(sc,
1442 				    sc->sc_txdescs[i].gd_addr));
1443 				if (i == txs->txs_lastdesc)
1444 					break;
1445 			}
1446 		}
1447 #endif
1448 
1449 		/*
1450 		 * In theory, we could harvest some descriptors before
1451 		 * the ring is empty, but that's a bit complicated.
1452 		 *
1453 		 * GEM_TX_COMPLETION points to the last descriptor
1454 		 * processed + 1.
1455 		 */
1456 		txlast = GEM_BANK1_READ_4(sc, GEM_TX_COMPLETION);
1457 #ifdef GEM_DEBUG
1458 		CTR4(KTR_GEM, "%s: txs->txs_firstdesc = %d, "
1459 		    "txs->txs_lastdesc = %d, txlast = %d",
1460 		    __func__, txs->txs_firstdesc, txs->txs_lastdesc, txlast);
1461 #endif
1462 		if (txs->txs_firstdesc <= txs->txs_lastdesc) {
1463 			if ((txlast >= txs->txs_firstdesc) &&
1464 			    (txlast <= txs->txs_lastdesc))
1465 				break;
1466 		} else {
1467 			/* Ick -- this command wraps. */
1468 			if ((txlast >= txs->txs_firstdesc) ||
1469 			    (txlast <= txs->txs_lastdesc))
1470 				break;
1471 		}
1472 
1473 #ifdef GEM_DEBUG
1474 		CTR1(KTR_GEM, "%s: releasing a descriptor", __func__);
1475 #endif
1476 		STAILQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
1477 
1478 		sc->sc_txfree += txs->txs_ndescs;
1479 
1480 		bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
1481 		    BUS_DMASYNC_POSTWRITE);
1482 		bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
1483 		if (txs->txs_mbuf != NULL) {
1484 			m_freem(txs->txs_mbuf);
1485 			txs->txs_mbuf = NULL;
1486 		}
1487 
1488 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
1489 
1490 		if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
1491 		progress = 1;
1492 	}
1493 
1494 #ifdef GEM_DEBUG
1495 	CTR4(KTR_GEM, "%s: GEM_TX_STATE_MACHINE %x GEM_TX_DATA_PTR %llx "
1496 	    "GEM_TX_COMPLETION %x",
1497 	    __func__, GEM_BANK1_READ_4(sc, GEM_TX_STATE_MACHINE),
1498 	    ((long long)GEM_BANK1_READ_4(sc, GEM_TX_DATA_PTR_HI) << 32) |
1499 	    GEM_BANK1_READ_4(sc, GEM_TX_DATA_PTR_LO),
1500 	    GEM_BANK1_READ_4(sc, GEM_TX_COMPLETION));
1501 #endif
1502 
1503 	if (progress) {
1504 		if (sc->sc_txfree == GEM_NTXDESC - 1)
1505 			sc->sc_txwin = 0;
1506 
1507 		/*
1508 		 * We freed some descriptors, so reset IFF_DRV_OACTIVE
1509 		 * and restart.
1510 		 */
1511 		ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
1512 		if (STAILQ_EMPTY(&sc->sc_txdirtyq))
1513 		    sc->sc_wdog_timer = 0;
1514 		gem_start_locked(ifp);
1515 	}
1516 
1517 #ifdef GEM_DEBUG
1518 	CTR3(KTR_GEM, "%s: %s: watchdog %d",
1519 	    device_get_name(sc->sc_dev), __func__, sc->sc_wdog_timer);
1520 #endif
1521 }
1522 
1523 #ifdef GEM_RINT_TIMEOUT
1524 static void
1525 gem_rint_timeout(void *arg)
1526 {
1527 	struct gem_softc *sc = arg;
1528 
1529 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1530 
1531 	gem_rint(sc);
1532 }
1533 #endif
1534 
1535 static void
1536 gem_rint(struct gem_softc *sc)
1537 {
1538 	struct ifnet *ifp = sc->sc_ifp;
1539 	struct mbuf *m;
1540 	uint64_t rxstat;
1541 	uint32_t rxcomp;
1542 
1543 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1544 
1545 #ifdef GEM_RINT_TIMEOUT
1546 	callout_stop(&sc->sc_rx_ch);
1547 #endif
1548 #ifdef GEM_DEBUG
1549 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
1550 #endif
1551 
1552 	/*
1553 	 * Read the completion register once.  This limits
1554 	 * how long the following loop can execute.
1555 	 */
1556 	rxcomp = GEM_BANK1_READ_4(sc, GEM_RX_COMPLETION);
1557 #ifdef GEM_DEBUG
1558 	CTR3(KTR_GEM, "%s: sc->sc_rxptr %d, complete %d",
1559 	    __func__, sc->sc_rxptr, rxcomp);
1560 #endif
1561 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
1562 	for (; sc->sc_rxptr != rxcomp;) {
1563 		m = sc->sc_rxsoft[sc->sc_rxptr].rxs_mbuf;
1564 		rxstat = GEM_DMA_READ(sc,
1565 		    sc->sc_rxdescs[sc->sc_rxptr].gd_flags);
1566 
1567 		if (rxstat & GEM_RD_OWN) {
1568 #ifdef GEM_RINT_TIMEOUT
1569 			/*
1570 			 * The descriptor is still marked as owned, although
1571 			 * it is supposed to have completed.  This has been
1572 			 * observed on some machines.  Just exiting here
1573 			 * might leave the packet sitting around until another
1574 			 * one arrives to trigger a new interrupt, which is
1575 			 * generally undesirable, so set up a timeout.
1576 			 */
1577 			callout_reset(&sc->sc_rx_ch, GEM_RXOWN_TICKS,
1578 			    gem_rint_timeout, sc);
1579 #endif
1580 			m = NULL;
1581 			goto kickit;
1582 		}
1583 
1584 		if (rxstat & GEM_RD_BAD_CRC) {
1585 			if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
1586 			device_printf(sc->sc_dev, "receive error: CRC error\n");
1587 			GEM_INIT_RXDESC(sc, sc->sc_rxptr);
1588 			m = NULL;
1589 			goto kickit;
1590 		}
1591 
1592 #ifdef GEM_DEBUG
1593 		if ((ifp->if_flags & IFF_DEBUG) != 0) {
1594 			printf("    rxsoft %p descriptor %d: ",
1595 			    &sc->sc_rxsoft[sc->sc_rxptr], sc->sc_rxptr);
1596 			printf("gd_flags: 0x%016llx\t",
1597 			    (long long)GEM_DMA_READ(sc,
1598 			    sc->sc_rxdescs[sc->sc_rxptr].gd_flags));
1599 			printf("gd_addr: 0x%016llx\n",
1600 			    (long long)GEM_DMA_READ(sc,
1601 			    sc->sc_rxdescs[sc->sc_rxptr].gd_addr));
1602 		}
1603 #endif
1604 
1605 		/*
1606 		 * Allocate a new mbuf cluster.  If that fails, we are
1607 		 * out of memory, and must drop the packet and recycle
1608 		 * the buffer that's already attached to this descriptor.
1609 		 */
1610 		if (gem_add_rxbuf(sc, sc->sc_rxptr) != 0) {
1611 			if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1);
1612 			GEM_INIT_RXDESC(sc, sc->sc_rxptr);
1613 			m = NULL;
1614 		}
1615 
1616  kickit:
1617 		/*
1618 		 * Update the RX kick register.  This register has to point
1619 		 * to the descriptor after the last valid one (before the
1620 		 * current batch) and for optimum performance should be
1621 		 * incremented in multiples of 4 (the DMA engine fetches/
1622 		 * updates descriptors in batches of 4).
1623 		 */
1624 		sc->sc_rxptr = GEM_NEXTRX(sc->sc_rxptr);
1625 		if ((sc->sc_rxptr % 4) == 0) {
1626 			GEM_CDSYNC(sc,
1627 			    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1628 			GEM_BANK1_WRITE_4(sc, GEM_RX_KICK,
1629 			    (sc->sc_rxptr + GEM_NRXDESC - 4) &
1630 			    GEM_NRXDESC_MASK);
1631 		}
1632 
1633 		if (m == NULL) {
1634 			if (rxstat & GEM_RD_OWN)
1635 				break;
1636 			continue;
1637 		}
1638 
1639 		if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
1640 		m->m_data += ETHER_ALIGN; /* first byte offset */
1641 		m->m_pkthdr.rcvif = ifp;
1642 		m->m_pkthdr.len = m->m_len = GEM_RD_BUFLEN(rxstat);
1643 
1644 		if ((ifp->if_capenable & IFCAP_RXCSUM) != 0)
1645 			gem_rxcksum(m, rxstat);
1646 
1647 		/* Pass it on. */
1648 		GEM_UNLOCK(sc);
1649 		(*ifp->if_input)(ifp, m);
1650 		GEM_LOCK(sc);
1651 	}
1652 
1653 #ifdef GEM_DEBUG
1654 	CTR3(KTR_GEM, "%s: done sc->sc_rxptr %d, complete %d", __func__,
1655 	    sc->sc_rxptr, GEM_BANK1_READ_4(sc, GEM_RX_COMPLETION));
1656 #endif
1657 }
1658 
1659 static int
1660 gem_add_rxbuf(struct gem_softc *sc, int idx)
1661 {
1662 	struct gem_rxsoft *rxs = &sc->sc_rxsoft[idx];
1663 	struct mbuf *m;
1664 	bus_dma_segment_t segs[1];
1665 	int error, nsegs;
1666 
1667 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1668 
1669 	m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
1670 	if (m == NULL)
1671 		return (ENOBUFS);
1672 	m->m_len = m->m_pkthdr.len = m->m_ext.ext_size;
1673 
1674 #ifdef GEM_DEBUG
1675 	/* Bzero the packet to check DMA. */
1676 	memset(m->m_ext.ext_buf, 0, m->m_ext.ext_size);
1677 #endif
1678 
1679 	if (rxs->rxs_mbuf != NULL) {
1680 		bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
1681 		    BUS_DMASYNC_POSTREAD);
1682 		bus_dmamap_unload(sc->sc_rdmatag, rxs->rxs_dmamap);
1683 	}
1684 
1685 	error = bus_dmamap_load_mbuf_sg(sc->sc_rdmatag, rxs->rxs_dmamap,
1686 	    m, segs, &nsegs, BUS_DMA_NOWAIT);
1687 	if (error != 0) {
1688 		device_printf(sc->sc_dev,
1689 		    "cannot load RS DMA map %d, error = %d\n", idx, error);
1690 		m_freem(m);
1691 		return (error);
1692 	}
1693 	/* If nsegs is wrong then the stack is corrupt. */
1694 	KASSERT(nsegs == 1,
1695 	    ("%s: too many DMA segments (%d)", __func__, nsegs));
1696 	rxs->rxs_mbuf = m;
1697 	rxs->rxs_paddr = segs[0].ds_addr;
1698 
1699 	bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
1700 	    BUS_DMASYNC_PREREAD);
1701 
1702 	GEM_INIT_RXDESC(sc, idx);
1703 
1704 	return (0);
1705 }
1706 
1707 static void
1708 gem_eint(struct gem_softc *sc, u_int status)
1709 {
1710 
1711 	if_inc_counter(sc->sc_ifp, IFCOUNTER_IERRORS, 1);
1712 	if ((status & GEM_INTR_RX_TAG_ERR) != 0) {
1713 		gem_reset_rxdma(sc);
1714 		return;
1715 	}
1716 
1717 	device_printf(sc->sc_dev, "%s: status 0x%x", __func__, status);
1718 	if ((status & GEM_INTR_BERR) != 0) {
1719 		if ((sc->sc_flags & GEM_PCI) != 0)
1720 			printf(", PCI bus error 0x%x\n",
1721 			    GEM_BANK1_READ_4(sc, GEM_PCI_ERROR_STATUS));
1722 		else
1723 			printf(", SBus error 0x%x\n",
1724 			    GEM_BANK1_READ_4(sc, GEM_SBUS_STATUS));
1725 	}
1726 }
1727 
1728 void
1729 gem_intr(void *v)
1730 {
1731 	struct gem_softc *sc = v;
1732 	uint32_t status, status2;
1733 
1734 	GEM_LOCK(sc);
1735 	status = GEM_BANK1_READ_4(sc, GEM_STATUS);
1736 
1737 #ifdef GEM_DEBUG
1738 	CTR4(KTR_GEM, "%s: %s: cplt %x, status %x",
1739 	    device_get_name(sc->sc_dev), __func__,
1740 	    (status >> GEM_STATUS_TX_COMPLETION_SHFT), (u_int)status);
1741 
1742 	/*
1743 	 * PCS interrupts must be cleared, otherwise no traffic is passed!
1744 	 */
1745 	if ((status & GEM_INTR_PCS) != 0) {
1746 		status2 =
1747 		    GEM_BANK1_READ_4(sc, GEM_MII_INTERRUP_STATUS) |
1748 		    GEM_BANK1_READ_4(sc, GEM_MII_INTERRUP_STATUS);
1749 		if ((status2 & GEM_MII_INTERRUP_LINK) != 0)
1750 			device_printf(sc->sc_dev,
1751 			    "%s: PCS link status changed\n", __func__);
1752 	}
1753 	if ((status & GEM_MAC_CONTROL_STATUS) != 0) {
1754 		status2 = GEM_BANK1_READ_4(sc, GEM_MAC_CONTROL_STATUS);
1755 		if ((status2 & GEM_MAC_PAUSED) != 0)
1756 			device_printf(sc->sc_dev,
1757 			    "%s: PAUSE received (PAUSE time %d slots)\n",
1758 			    __func__, GEM_MAC_PAUSE_TIME(status2));
1759 		if ((status2 & GEM_MAC_PAUSE) != 0)
1760 			device_printf(sc->sc_dev,
1761 			    "%s: transited to PAUSE state\n", __func__);
1762 		if ((status2 & GEM_MAC_RESUME) != 0)
1763 			device_printf(sc->sc_dev,
1764 			    "%s: transited to non-PAUSE state\n", __func__);
1765 	}
1766 	if ((status & GEM_INTR_MIF) != 0)
1767 		device_printf(sc->sc_dev, "%s: MIF interrupt\n", __func__);
1768 #endif
1769 
1770 	if (__predict_false(status &
1771 	    (GEM_INTR_RX_TAG_ERR | GEM_INTR_PERR | GEM_INTR_BERR)) != 0)
1772 		gem_eint(sc, status);
1773 
1774 	if ((status & (GEM_INTR_RX_DONE | GEM_INTR_RX_NOBUF)) != 0)
1775 		gem_rint(sc);
1776 
1777 	if ((status & (GEM_INTR_TX_EMPTY | GEM_INTR_TX_INTME)) != 0)
1778 		gem_tint(sc);
1779 
1780 	if (__predict_false((status & GEM_INTR_TX_MAC) != 0)) {
1781 		status2 = GEM_BANK1_READ_4(sc, GEM_MAC_TX_STATUS);
1782 		if ((status2 &
1783 		    ~(GEM_MAC_TX_XMIT_DONE | GEM_MAC_TX_DEFER_EXP |
1784 		    GEM_MAC_TX_PEAK_EXP)) != 0)
1785 			device_printf(sc->sc_dev,
1786 			    "MAC TX fault, status %x\n", status2);
1787 		if ((status2 &
1788 		    (GEM_MAC_TX_UNDERRUN | GEM_MAC_TX_PKT_TOO_LONG)) != 0) {
1789 			if_inc_counter(sc->sc_ifp, IFCOUNTER_OERRORS, 1);
1790 			sc->sc_ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
1791 			gem_init_locked(sc);
1792 		}
1793 	}
1794 	if (__predict_false((status & GEM_INTR_RX_MAC) != 0)) {
1795 		status2 = GEM_BANK1_READ_4(sc, GEM_MAC_RX_STATUS);
1796 		/*
1797 		 * At least with GEM_SUN_GEM and some GEM_SUN_ERI
1798 		 * revisions GEM_MAC_RX_OVERFLOW happen often due to a
1799 		 * silicon bug so handle them silently.  Moreover, it's
1800 		 * likely that the receiver has hung so we reset it.
1801 		 */
1802 		if ((status2 & GEM_MAC_RX_OVERFLOW) != 0) {
1803 			if_inc_counter(sc->sc_ifp, IFCOUNTER_IERRORS, 1);
1804 			gem_reset_rxdma(sc);
1805 		} else if ((status2 &
1806 		    ~(GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT)) != 0)
1807 			device_printf(sc->sc_dev,
1808 			    "MAC RX fault, status %x\n", status2);
1809 	}
1810 	GEM_UNLOCK(sc);
1811 }
1812 
1813 static int
1814 gem_watchdog(struct gem_softc *sc)
1815 {
1816 	struct ifnet *ifp = sc->sc_ifp;
1817 
1818 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1819 
1820 #ifdef GEM_DEBUG
1821 	CTR4(KTR_GEM,
1822 	    "%s: GEM_RX_CONFIG %x GEM_MAC_RX_STATUS %x GEM_MAC_RX_CONFIG %x",
1823 	    __func__, GEM_BANK1_READ_4(sc, GEM_RX_CONFIG),
1824 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_STATUS),
1825 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG));
1826 	CTR4(KTR_GEM,
1827 	    "%s: GEM_TX_CONFIG %x GEM_MAC_TX_STATUS %x GEM_MAC_TX_CONFIG %x",
1828 	    __func__, GEM_BANK1_READ_4(sc, GEM_TX_CONFIG),
1829 	    GEM_BANK1_READ_4(sc, GEM_MAC_TX_STATUS),
1830 	    GEM_BANK1_READ_4(sc, GEM_MAC_TX_CONFIG));
1831 #endif
1832 
1833 	if (sc->sc_wdog_timer == 0 || --sc->sc_wdog_timer != 0)
1834 		return (0);
1835 
1836 	if ((sc->sc_flags & GEM_LINK) != 0)
1837 		device_printf(sc->sc_dev, "device timeout\n");
1838 	else if (bootverbose)
1839 		device_printf(sc->sc_dev, "device timeout (no link)\n");
1840 	if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
1841 
1842 	/* Try to get more packets going. */
1843 	ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
1844 	gem_init_locked(sc);
1845 	gem_start_locked(ifp);
1846 	return (EJUSTRETURN);
1847 }
1848 
1849 static void
1850 gem_mifinit(struct gem_softc *sc)
1851 {
1852 
1853 	/* Configure the MIF in frame mode. */
1854 	GEM_BANK1_WRITE_4(sc, GEM_MIF_CONFIG,
1855 	    GEM_BANK1_READ_4(sc, GEM_MIF_CONFIG) & ~GEM_MIF_CONFIG_BB_ENA);
1856 	GEM_BANK1_BARRIER(sc, GEM_MIF_CONFIG, 4,
1857 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1858 }
1859 
1860 /*
1861  * MII interface
1862  *
1863  * The MII interface supports at least three different operating modes:
1864  *
1865  * Bitbang mode is implemented using data, clock and output enable registers.
1866  *
1867  * Frame mode is implemented by loading a complete frame into the frame
1868  * register and polling the valid bit for completion.
1869  *
1870  * Polling mode uses the frame register but completion is indicated by
1871  * an interrupt.
1872  *
1873  */
1874 int
1875 gem_mii_readreg(device_t dev, int phy, int reg)
1876 {
1877 	struct gem_softc *sc;
1878 	int n;
1879 	uint32_t v;
1880 
1881 #ifdef GEM_DEBUG_PHY
1882 	printf("%s: phy %d reg %d\n", __func__, phy, reg);
1883 #endif
1884 
1885 	sc = device_get_softc(dev);
1886 	if ((sc->sc_flags & GEM_SERDES) != 0) {
1887 		switch (reg) {
1888 		case MII_BMCR:
1889 			reg = GEM_MII_CONTROL;
1890 			break;
1891 		case MII_BMSR:
1892 			reg = GEM_MII_STATUS;
1893 			break;
1894 		case MII_PHYIDR1:
1895 		case MII_PHYIDR2:
1896 			return (0);
1897 		case MII_ANAR:
1898 			reg = GEM_MII_ANAR;
1899 			break;
1900 		case MII_ANLPAR:
1901 			reg = GEM_MII_ANLPAR;
1902 			break;
1903 		case MII_EXTSR:
1904 			return (EXTSR_1000XFDX | EXTSR_1000XHDX);
1905 		default:
1906 			device_printf(sc->sc_dev,
1907 			    "%s: unhandled register %d\n", __func__, reg);
1908 			return (0);
1909 		}
1910 		return (GEM_BANK1_READ_4(sc, reg));
1911 	}
1912 
1913 	/* Construct the frame command. */
1914 	v = GEM_MIF_FRAME_READ |
1915 	    (phy << GEM_MIF_PHY_SHIFT) |
1916 	    (reg << GEM_MIF_REG_SHIFT);
1917 
1918 	GEM_BANK1_WRITE_4(sc, GEM_MIF_FRAME, v);
1919 	GEM_BANK1_BARRIER(sc, GEM_MIF_FRAME, 4,
1920 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1921 	for (n = 0; n < 100; n++) {
1922 		DELAY(1);
1923 		v = GEM_BANK1_READ_4(sc, GEM_MIF_FRAME);
1924 		if (v & GEM_MIF_FRAME_TA0)
1925 			return (v & GEM_MIF_FRAME_DATA);
1926 	}
1927 
1928 	device_printf(sc->sc_dev, "%s: timed out\n", __func__);
1929 	return (0);
1930 }
1931 
1932 int
1933 gem_mii_writereg(device_t dev, int phy, int reg, int val)
1934 {
1935 	struct gem_softc *sc;
1936 	int n;
1937 	uint32_t v;
1938 
1939 #ifdef GEM_DEBUG_PHY
1940 	printf("%s: phy %d reg %d val %x\n", phy, reg, val, __func__);
1941 #endif
1942 
1943 	sc = device_get_softc(dev);
1944 	if ((sc->sc_flags & GEM_SERDES) != 0) {
1945 		switch (reg) {
1946 		case MII_BMSR:
1947 			reg = GEM_MII_STATUS;
1948 			break;
1949 		case MII_BMCR:
1950 			reg = GEM_MII_CONTROL;
1951 			if ((val & GEM_MII_CONTROL_RESET) == 0)
1952 				break;
1953 			GEM_BANK1_WRITE_4(sc, GEM_MII_CONTROL, val);
1954 			GEM_BANK1_BARRIER(sc, GEM_MII_CONTROL, 4,
1955 			    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1956 			if (!GEM_BANK1_BITWAIT(sc, GEM_MII_CONTROL,
1957 			    GEM_MII_CONTROL_RESET, 0))
1958 				device_printf(sc->sc_dev,
1959 				    "cannot reset PCS\n");
1960 			/* FALLTHROUGH */
1961 		case MII_ANAR:
1962 			GEM_BANK1_WRITE_4(sc, GEM_MII_CONFIG, 0);
1963 			GEM_BANK1_BARRIER(sc, GEM_MII_CONFIG, 4,
1964 			    BUS_SPACE_BARRIER_WRITE);
1965 			GEM_BANK1_WRITE_4(sc, GEM_MII_ANAR, val);
1966 			GEM_BANK1_BARRIER(sc, GEM_MII_ANAR, 4,
1967 			    BUS_SPACE_BARRIER_WRITE);
1968 			GEM_BANK1_WRITE_4(sc, GEM_MII_SLINK_CONTROL,
1969 			    GEM_MII_SLINK_LOOPBACK | GEM_MII_SLINK_EN_SYNC_D);
1970 			GEM_BANK1_BARRIER(sc, GEM_MII_SLINK_CONTROL, 4,
1971 			    BUS_SPACE_BARRIER_WRITE);
1972 			GEM_BANK1_WRITE_4(sc, GEM_MII_CONFIG,
1973 			    GEM_MII_CONFIG_ENABLE);
1974 			GEM_BANK1_BARRIER(sc, GEM_MII_CONFIG, 4,
1975 			    BUS_SPACE_BARRIER_WRITE);
1976 			return (0);
1977 		case MII_ANLPAR:
1978 			reg = GEM_MII_ANLPAR;
1979 			break;
1980 		default:
1981 			device_printf(sc->sc_dev,
1982 			    "%s: unhandled register %d\n", __func__, reg);
1983 			return (0);
1984 		}
1985 		GEM_BANK1_WRITE_4(sc, reg, val);
1986 		GEM_BANK1_BARRIER(sc, reg, 4,
1987 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1988 		return (0);
1989 	}
1990 
1991 	/* Construct the frame command. */
1992 	v = GEM_MIF_FRAME_WRITE |
1993 	    (phy << GEM_MIF_PHY_SHIFT) |
1994 	    (reg << GEM_MIF_REG_SHIFT) |
1995 	    (val & GEM_MIF_FRAME_DATA);
1996 
1997 	GEM_BANK1_WRITE_4(sc, GEM_MIF_FRAME, v);
1998 	GEM_BANK1_BARRIER(sc, GEM_MIF_FRAME, 4,
1999 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
2000 	for (n = 0; n < 100; n++) {
2001 		DELAY(1);
2002 		v = GEM_BANK1_READ_4(sc, GEM_MIF_FRAME);
2003 		if (v & GEM_MIF_FRAME_TA0)
2004 			return (1);
2005 	}
2006 
2007 	device_printf(sc->sc_dev, "%s: timed out\n", __func__);
2008 	return (0);
2009 }
2010 
2011 void
2012 gem_mii_statchg(device_t dev)
2013 {
2014 	struct gem_softc *sc;
2015 	int gigabit;
2016 	uint32_t rxcfg, txcfg, v;
2017 
2018 	sc = device_get_softc(dev);
2019 
2020 	GEM_LOCK_ASSERT(sc, MA_OWNED);
2021 
2022 #ifdef GEM_DEBUG
2023 	if ((sc->sc_ifp->if_flags & IFF_DEBUG) != 0)
2024 		device_printf(sc->sc_dev, "%s: status change\n", __func__);
2025 #endif
2026 
2027 	if ((sc->sc_mii->mii_media_status & IFM_ACTIVE) != 0 &&
2028 	    IFM_SUBTYPE(sc->sc_mii->mii_media_active) != IFM_NONE)
2029 		sc->sc_flags |= GEM_LINK;
2030 	else
2031 		sc->sc_flags &= ~GEM_LINK;
2032 
2033 	switch (IFM_SUBTYPE(sc->sc_mii->mii_media_active)) {
2034 	case IFM_1000_SX:
2035 	case IFM_1000_LX:
2036 	case IFM_1000_CX:
2037 	case IFM_1000_T:
2038 		gigabit = 1;
2039 		break;
2040 	default:
2041 		gigabit = 0;
2042 	}
2043 
2044 	/*
2045 	 * The configuration done here corresponds to the steps F) and
2046 	 * G) and as far as enabling of RX and TX MAC goes also step H)
2047 	 * of the initialization sequence outlined in section 3.2.1 of
2048 	 * the GEM Gigabit Ethernet ASIC Specification.
2049 	 */
2050 
2051 	rxcfg = sc->sc_mac_rxcfg;
2052 	rxcfg &= ~GEM_MAC_RX_CARR_EXTEND;
2053 	txcfg = GEM_MAC_TX_ENA_IPG0 | GEM_MAC_TX_NGU | GEM_MAC_TX_NGU_LIMIT;
2054 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) != 0)
2055 		txcfg |= GEM_MAC_TX_IGN_CARRIER | GEM_MAC_TX_IGN_COLLIS;
2056 	else if (gigabit != 0) {
2057 		rxcfg |= GEM_MAC_RX_CARR_EXTEND;
2058 		txcfg |= GEM_MAC_TX_CARR_EXTEND;
2059 	}
2060 	(void)gem_disable_tx(sc);
2061 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG, txcfg);
2062 	(void)gem_disable_rx(sc);
2063 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, rxcfg);
2064 
2065 	v = GEM_BANK1_READ_4(sc, GEM_MAC_CONTROL_CONFIG) &
2066 	    ~(GEM_MAC_CC_RX_PAUSE | GEM_MAC_CC_TX_PAUSE);
2067 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
2068 	    IFM_ETH_RXPAUSE) != 0)
2069 		v |= GEM_MAC_CC_RX_PAUSE;
2070 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
2071 	    IFM_ETH_TXPAUSE) != 0)
2072 		v |= GEM_MAC_CC_TX_PAUSE;
2073 	GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_CONFIG, v);
2074 
2075 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) == 0 &&
2076 	    gigabit != 0)
2077 		GEM_BANK1_WRITE_4(sc, GEM_MAC_SLOT_TIME,
2078 		    GEM_MAC_SLOT_TIME_CARR_EXTEND);
2079 	else
2080 		GEM_BANK1_WRITE_4(sc, GEM_MAC_SLOT_TIME,
2081 		    GEM_MAC_SLOT_TIME_NORMAL);
2082 
2083 	/* XIF Configuration */
2084 	v = GEM_MAC_XIF_LINK_LED;
2085 	v |= GEM_MAC_XIF_TX_MII_ENA;
2086 	if ((sc->sc_flags & GEM_SERDES) == 0) {
2087 		if ((GEM_BANK1_READ_4(sc, GEM_MIF_CONFIG) &
2088 		    GEM_MIF_CONFIG_PHY_SEL) != 0) {
2089 			/* External MII needs echo disable if half duplex. */
2090 			if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
2091 			    IFM_FDX) == 0)
2092 				v |= GEM_MAC_XIF_ECHO_DISABL;
2093 		} else
2094 			/*
2095 			 * Internal MII needs buffer enable.
2096 			 * XXX buffer enable makes only sense for an
2097 			 * external PHY.
2098 			 */
2099 			v |= GEM_MAC_XIF_MII_BUF_ENA;
2100 	}
2101 	if (gigabit != 0)
2102 		v |= GEM_MAC_XIF_GMII_MODE;
2103 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) != 0)
2104 		v |= GEM_MAC_XIF_FDPLX_LED;
2105 	GEM_BANK1_WRITE_4(sc, GEM_MAC_XIF_CONFIG, v);
2106 
2107 	sc->sc_mac_rxcfg = rxcfg;
2108 	if ((sc->sc_ifp->if_drv_flags & IFF_DRV_RUNNING) != 0 &&
2109 	    (sc->sc_flags & GEM_LINK) != 0) {
2110 		GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG,
2111 		    txcfg | GEM_MAC_TX_ENABLE);
2112 		GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG,
2113 		    rxcfg | GEM_MAC_RX_ENABLE);
2114 	}
2115 }
2116 
2117 int
2118 gem_mediachange(struct ifnet *ifp)
2119 {
2120 	struct gem_softc *sc = ifp->if_softc;
2121 	int error;
2122 
2123 	/* XXX add support for serial media. */
2124 
2125 	GEM_LOCK(sc);
2126 	error = mii_mediachg(sc->sc_mii);
2127 	GEM_UNLOCK(sc);
2128 	return (error);
2129 }
2130 
2131 void
2132 gem_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
2133 {
2134 	struct gem_softc *sc = ifp->if_softc;
2135 
2136 	GEM_LOCK(sc);
2137 	if ((ifp->if_flags & IFF_UP) == 0) {
2138 		GEM_UNLOCK(sc);
2139 		return;
2140 	}
2141 
2142 	mii_pollstat(sc->sc_mii);
2143 	ifmr->ifm_active = sc->sc_mii->mii_media_active;
2144 	ifmr->ifm_status = sc->sc_mii->mii_media_status;
2145 	GEM_UNLOCK(sc);
2146 }
2147 
2148 static int
2149 gem_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
2150 {
2151 	struct gem_softc *sc = ifp->if_softc;
2152 	struct ifreq *ifr = (struct ifreq *)data;
2153 	int error;
2154 
2155 	error = 0;
2156 	switch (cmd) {
2157 	case SIOCSIFFLAGS:
2158 		GEM_LOCK(sc);
2159 		if ((ifp->if_flags & IFF_UP) != 0) {
2160 			if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0 &&
2161 			    ((ifp->if_flags ^ sc->sc_ifflags) &
2162 			    (IFF_ALLMULTI | IFF_PROMISC)) != 0)
2163 				gem_setladrf(sc);
2164 			else
2165 				gem_init_locked(sc);
2166 		} else if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
2167 			gem_stop(ifp, 0);
2168 		if ((ifp->if_flags & IFF_LINK0) != 0)
2169 			sc->sc_csum_features |= CSUM_UDP;
2170 		else
2171 			sc->sc_csum_features &= ~CSUM_UDP;
2172 		if ((ifp->if_capenable & IFCAP_TXCSUM) != 0)
2173 			ifp->if_hwassist = sc->sc_csum_features;
2174 		sc->sc_ifflags = ifp->if_flags;
2175 		GEM_UNLOCK(sc);
2176 		break;
2177 	case SIOCADDMULTI:
2178 	case SIOCDELMULTI:
2179 		GEM_LOCK(sc);
2180 		if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
2181 			gem_setladrf(sc);
2182 		GEM_UNLOCK(sc);
2183 		break;
2184 	case SIOCGIFMEDIA:
2185 	case SIOCSIFMEDIA:
2186 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii->mii_media, cmd);
2187 		break;
2188 	case SIOCSIFCAP:
2189 		GEM_LOCK(sc);
2190 		ifp->if_capenable = ifr->ifr_reqcap;
2191 		if ((ifp->if_capenable & IFCAP_TXCSUM) != 0)
2192 			ifp->if_hwassist = sc->sc_csum_features;
2193 		else
2194 			ifp->if_hwassist = 0;
2195 		GEM_UNLOCK(sc);
2196 		break;
2197 	default:
2198 		error = ether_ioctl(ifp, cmd, data);
2199 		break;
2200 	}
2201 
2202 	return (error);
2203 }
2204 
2205 static u_int
2206 gem_hash_maddr(void *arg, struct sockaddr_dl *sdl, u_int cnt)
2207 {
2208 	uint32_t crc, *hash = arg;
2209 
2210 	crc = ether_crc32_le(LLADDR(sdl), ETHER_ADDR_LEN);
2211 	/* We just want the 8 most significant bits. */
2212 	crc >>= 24;
2213 	/* Set the corresponding bit in the filter. */
2214 	hash[crc >> 4] |= 1 << (15 - (crc & 15));
2215 
2216 	return (1);
2217 }
2218 
2219 static void
2220 gem_setladrf(struct gem_softc *sc)
2221 {
2222 	struct ifnet *ifp = sc->sc_ifp;
2223 	int i;
2224 	uint32_t hash[16];
2225 	uint32_t v;
2226 
2227 	GEM_LOCK_ASSERT(sc, MA_OWNED);
2228 
2229 	/*
2230 	 * Turn off the RX MAC and the hash filter as required by the Sun GEM
2231 	 * programming restrictions.
2232 	 */
2233 	v = sc->sc_mac_rxcfg & ~GEM_MAC_RX_HASH_FILTER;
2234 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, v);
2235 	GEM_BANK1_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
2236 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
2237 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_HASH_FILTER |
2238 	    GEM_MAC_RX_ENABLE, 0))
2239 		device_printf(sc->sc_dev,
2240 		    "cannot disable RX MAC or hash filter\n");
2241 
2242 	v &= ~(GEM_MAC_RX_PROMISCUOUS | GEM_MAC_RX_PROMISC_GRP);
2243 	if ((ifp->if_flags & IFF_PROMISC) != 0) {
2244 		v |= GEM_MAC_RX_PROMISCUOUS;
2245 		goto chipit;
2246 	}
2247 	if ((ifp->if_flags & IFF_ALLMULTI) != 0) {
2248 		v |= GEM_MAC_RX_PROMISC_GRP;
2249 		goto chipit;
2250 	}
2251 
2252 	/*
2253 	 * Set up multicast address filter by passing all multicast
2254 	 * addresses through a crc generator, and then using the high
2255 	 * order 8 bits as an index into the 256 bit logical address
2256 	 * filter.  The high order 4 bits selects the word, while the
2257 	 * other 4 bits select the bit within the word (where bit 0
2258 	 * is the MSB).
2259 	 */
2260 
2261 	memset(hash, 0, sizeof(hash));
2262 	if_foreach_llmaddr(ifp, gem_hash_maddr, hash);
2263 
2264 	v |= GEM_MAC_RX_HASH_FILTER;
2265 
2266 	/* Now load the hash table into the chip (if we are using it). */
2267 	for (i = 0; i < 16; i++)
2268 		GEM_BANK1_WRITE_4(sc,
2269 		    GEM_MAC_HASH0 + i * (GEM_MAC_HASH1 - GEM_MAC_HASH0),
2270 		    hash[i]);
2271 
2272  chipit:
2273 	sc->sc_mac_rxcfg = v;
2274 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, v | GEM_MAC_RX_ENABLE);
2275 }
2276