xref: /freebsd/sys/dev/gem/if_gem.c (revision fcb560670601b2a4d87bb31d7531c8dcc37ee71b)
1 /*-
2  * Copyright (C) 2001 Eduardo Horvath.
3  * Copyright (c) 2001-2003 Thomas Moestl
4  * Copyright (c) 2007 Marius Strobl <marius@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR  ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR  BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  *	from: NetBSD: gem.c,v 1.21 2002/06/01 23:50:58 lukem Exp
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 /*
35  * Driver for Apple GMAC, Sun ERI and Sun GEM Ethernet controllers
36  */
37 
38 #if 0
39 #define	GEM_DEBUG
40 #endif
41 
42 #if 0	/* XXX: In case of emergency, re-enable this. */
43 #define	GEM_RINT_TIMEOUT
44 #endif
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/bus.h>
49 #include <sys/callout.h>
50 #include <sys/endian.h>
51 #include <sys/mbuf.h>
52 #include <sys/malloc.h>
53 #include <sys/kernel.h>
54 #include <sys/lock.h>
55 #include <sys/module.h>
56 #include <sys/mutex.h>
57 #include <sys/socket.h>
58 #include <sys/sockio.h>
59 #include <sys/rman.h>
60 
61 #include <net/bpf.h>
62 #include <net/ethernet.h>
63 #include <net/if.h>
64 #include <net/if_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, u_int bank, bus_addr_t r,
101 		    uint32_t clr, 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(struct ifnet *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(struct ifnet *ifp);
127 static void	gem_start_locked(struct ifnet *ifp);
128 static void	gem_stop(struct ifnet *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 devclass_t gem_devclass;
135 DRIVER_MODULE(miibus, gem, miibus_driver, miibus_devclass, 0, 0);
136 MODULE_DEPEND(gem, miibus, 1, 1, 1);
137 
138 #ifdef GEM_DEBUG
139 #include <sys/ktr.h>
140 #define	KTR_GEM		KTR_SPARE2
141 #endif
142 
143 #define	GEM_BANK1_BITWAIT(sc, r, clr, set)				\
144 	gem_bitwait((sc), GEM_RES_BANK1, (r), (clr), (set))
145 #define	GEM_BANK2_BITWAIT(sc, r, clr, set)				\
146 	gem_bitwait((sc), GEM_RES_BANK2, (r), (clr), (set))
147 
148 int
149 gem_attach(struct gem_softc *sc)
150 {
151 	struct gem_txsoft *txs;
152 	struct ifnet *ifp;
153 	int error, i, phy;
154 	uint32_t v;
155 
156 	if (bootverbose)
157 		device_printf(sc->sc_dev, "flags=0x%x\n", sc->sc_flags);
158 
159 	/* Set up ifnet structure. */
160 	ifp = sc->sc_ifp = if_alloc(IFT_ETHER);
161 	if (ifp == NULL)
162 		return (ENOSPC);
163 	sc->sc_csum_features = GEM_CSUM_FEATURES;
164 	ifp->if_softc = sc;
165 	if_initname(ifp, device_get_name(sc->sc_dev),
166 	    device_get_unit(sc->sc_dev));
167 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
168 	ifp->if_start = gem_start;
169 	ifp->if_ioctl = gem_ioctl;
170 	ifp->if_init = gem_init;
171 	IFQ_SET_MAXLEN(&ifp->if_snd, GEM_TXQUEUELEN);
172 	ifp->if_snd.ifq_drv_maxlen = GEM_TXQUEUELEN;
173 	IFQ_SET_READY(&ifp->if_snd);
174 
175 	callout_init_mtx(&sc->sc_tick_ch, &sc->sc_mtx, 0);
176 #ifdef GEM_RINT_TIMEOUT
177 	callout_init_mtx(&sc->sc_rx_ch, &sc->sc_mtx, 0);
178 #endif
179 
180 	/* Make sure the chip is stopped. */
181 	gem_reset(sc);
182 
183 	error = bus_dma_tag_create(bus_get_dma_tag(sc->sc_dev), 1, 0,
184 	    BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL,
185 	    BUS_SPACE_MAXSIZE_32BIT, 0, BUS_SPACE_MAXSIZE_32BIT, 0, NULL,
186 	    NULL, &sc->sc_pdmatag);
187 	if (error != 0)
188 		goto fail_ifnet;
189 
190 	error = bus_dma_tag_create(sc->sc_pdmatag, 1, 0,
191 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL, MCLBYTES,
192 	    1, MCLBYTES, BUS_DMA_ALLOCNOW, NULL, NULL, &sc->sc_rdmatag);
193 	if (error != 0)
194 		goto fail_ptag;
195 
196 	error = bus_dma_tag_create(sc->sc_pdmatag, 1, 0,
197 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
198 	    MCLBYTES * GEM_NTXSEGS, GEM_NTXSEGS, MCLBYTES,
199 	    BUS_DMA_ALLOCNOW, NULL, NULL, &sc->sc_tdmatag);
200 	if (error != 0)
201 		goto fail_rtag;
202 
203 	error = bus_dma_tag_create(sc->sc_pdmatag, PAGE_SIZE, 0,
204 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
205 	    sizeof(struct gem_control_data), 1,
206 	    sizeof(struct gem_control_data), 0,
207 	    NULL, NULL, &sc->sc_cdmatag);
208 	if (error != 0)
209 		goto fail_ttag;
210 
211 	/*
212 	 * Allocate the control data structures, create and load the
213 	 * DMA map for it.
214 	 */
215 	if ((error = bus_dmamem_alloc(sc->sc_cdmatag,
216 	    (void **)&sc->sc_control_data,
217 	    BUS_DMA_WAITOK | BUS_DMA_COHERENT | BUS_DMA_ZERO,
218 	    &sc->sc_cddmamap)) != 0) {
219 		device_printf(sc->sc_dev,
220 		    "unable to allocate control data, error = %d\n", error);
221 		goto fail_ctag;
222 	}
223 
224 	sc->sc_cddma = 0;
225 	if ((error = bus_dmamap_load(sc->sc_cdmatag, sc->sc_cddmamap,
226 	    sc->sc_control_data, sizeof(struct gem_control_data),
227 	    gem_cddma_callback, sc, 0)) != 0 || sc->sc_cddma == 0) {
228 		device_printf(sc->sc_dev,
229 		    "unable to load control data DMA map, error = %d\n",
230 		    error);
231 		goto fail_cmem;
232 	}
233 
234 	/*
235 	 * Initialize the transmit job descriptors.
236 	 */
237 	STAILQ_INIT(&sc->sc_txfreeq);
238 	STAILQ_INIT(&sc->sc_txdirtyq);
239 
240 	/*
241 	 * Create the transmit buffer DMA maps.
242 	 */
243 	error = ENOMEM;
244 	for (i = 0; i < GEM_TXQUEUELEN; i++) {
245 		txs = &sc->sc_txsoft[i];
246 		txs->txs_mbuf = NULL;
247 		txs->txs_ndescs = 0;
248 		if ((error = bus_dmamap_create(sc->sc_tdmatag, 0,
249 		    &txs->txs_dmamap)) != 0) {
250 			device_printf(sc->sc_dev,
251 			    "unable to create TX DMA map %d, error = %d\n",
252 			    i, error);
253 			goto fail_txd;
254 		}
255 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
256 	}
257 
258 	/*
259 	 * Create the receive buffer DMA maps.
260 	 */
261 	for (i = 0; i < GEM_NRXDESC; i++) {
262 		if ((error = bus_dmamap_create(sc->sc_rdmatag, 0,
263 		    &sc->sc_rxsoft[i].rxs_dmamap)) != 0) {
264 			device_printf(sc->sc_dev,
265 			    "unable to create RX DMA map %d, error = %d\n",
266 			    i, error);
267 			goto fail_rxd;
268 		}
269 		sc->sc_rxsoft[i].rxs_mbuf = NULL;
270 	}
271 
272 	/* Bypass probing PHYs if we already know for sure to use a SERDES. */
273 	if ((sc->sc_flags & GEM_SERDES) != 0)
274 		goto serdes;
275 
276 	/* Bad things will happen when touching this register on ERI. */
277 	if (sc->sc_variant != GEM_SUN_ERI) {
278 		GEM_BANK1_WRITE_4(sc, GEM_MII_DATAPATH_MODE,
279 		    GEM_MII_DATAPATH_MII);
280 		GEM_BANK1_BARRIER(sc, GEM_MII_DATAPATH_MODE, 4,
281 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
282 	}
283 
284 	gem_mifinit(sc);
285 
286 	/*
287 	 * Look for an external PHY.
288 	 */
289 	error = ENXIO;
290 	v = GEM_BANK1_READ_4(sc, GEM_MIF_CONFIG);
291 	if ((v & GEM_MIF_CONFIG_MDI1) != 0) {
292 		v |= GEM_MIF_CONFIG_PHY_SEL;
293 		GEM_BANK1_WRITE_4(sc, GEM_MIF_CONFIG, v);
294 		GEM_BANK1_BARRIER(sc, GEM_MIF_CONFIG, 4,
295 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
296 		switch (sc->sc_variant) {
297 		case GEM_SUN_ERI:
298 			phy = GEM_PHYAD_EXTERNAL;
299 			break;
300 		default:
301 			phy = MII_PHY_ANY;
302 			break;
303 		}
304 		error = mii_attach(sc->sc_dev, &sc->sc_miibus, ifp,
305 		    gem_mediachange, gem_mediastatus, BMSR_DEFCAPMASK, phy,
306 		    MII_OFFSET_ANY, MIIF_DOPAUSE);
307 	}
308 
309 	/*
310 	 * Fall back on an internal PHY if no external PHY was found.
311 	 * Note that with Apple (K2) GMACs GEM_MIF_CONFIG_MDI0 can't be
312 	 * trusted when the firmware has powered down the chip.
313 	 */
314 	if (error != 0 &&
315 	    ((v & GEM_MIF_CONFIG_MDI0) != 0 || GEM_IS_APPLE(sc))) {
316 		v &= ~GEM_MIF_CONFIG_PHY_SEL;
317 		GEM_BANK1_WRITE_4(sc, GEM_MIF_CONFIG, v);
318 		GEM_BANK1_BARRIER(sc, GEM_MIF_CONFIG, 4,
319 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
320 		switch (sc->sc_variant) {
321 		case GEM_SUN_ERI:
322 		case GEM_APPLE_K2_GMAC:
323 			phy = GEM_PHYAD_INTERNAL;
324 			break;
325 		case GEM_APPLE_GMAC:
326 			phy = GEM_PHYAD_EXTERNAL;
327 			break;
328 		default:
329 			phy = MII_PHY_ANY;
330 			break;
331 		}
332 		error = mii_attach(sc->sc_dev, &sc->sc_miibus, ifp,
333 		    gem_mediachange, gem_mediastatus, BMSR_DEFCAPMASK, phy,
334 		    MII_OFFSET_ANY, MIIF_DOPAUSE);
335 	}
336 
337 	/*
338 	 * Try the external PCS SERDES if we didn't find any PHYs.
339 	 */
340 	if (error != 0 && sc->sc_variant == GEM_SUN_GEM) {
341  serdes:
342 		GEM_BANK1_WRITE_4(sc, GEM_MII_DATAPATH_MODE,
343 		    GEM_MII_DATAPATH_SERDES);
344 		GEM_BANK1_BARRIER(sc, GEM_MII_DATAPATH_MODE, 4,
345 		    BUS_SPACE_BARRIER_WRITE);
346 		GEM_BANK1_WRITE_4(sc, GEM_MII_SLINK_CONTROL,
347 		    GEM_MII_SLINK_LOOPBACK | GEM_MII_SLINK_EN_SYNC_D);
348 		GEM_BANK1_BARRIER(sc, GEM_MII_SLINK_CONTROL, 4,
349 		    BUS_SPACE_BARRIER_WRITE);
350 		GEM_BANK1_WRITE_4(sc, GEM_MII_CONFIG, GEM_MII_CONFIG_ENABLE);
351 		GEM_BANK1_BARRIER(sc, GEM_MII_CONFIG, 4,
352 		    BUS_SPACE_BARRIER_WRITE);
353 		sc->sc_flags |= GEM_SERDES;
354 		error = mii_attach(sc->sc_dev, &sc->sc_miibus, ifp,
355 		    gem_mediachange, gem_mediastatus, BMSR_DEFCAPMASK,
356 		    GEM_PHYAD_EXTERNAL, MII_OFFSET_ANY, MIIF_DOPAUSE);
357 	}
358 	if (error != 0) {
359 		device_printf(sc->sc_dev, "attaching PHYs failed\n");
360 		goto fail_rxd;
361 	}
362 	sc->sc_mii = device_get_softc(sc->sc_miibus);
363 
364 	/*
365 	 * From this point forward, the attachment cannot fail.  A failure
366 	 * before this point releases all resources that may have been
367 	 * allocated.
368 	 */
369 
370 	/* Get RX FIFO size. */
371 	sc->sc_rxfifosize = 64 *
372 	    GEM_BANK1_READ_4(sc, GEM_RX_FIFO_SIZE);
373 
374 	/* Get TX FIFO size. */
375 	v = GEM_BANK1_READ_4(sc, GEM_TX_FIFO_SIZE);
376 	device_printf(sc->sc_dev, "%ukB RX FIFO, %ukB TX FIFO\n",
377 	    sc->sc_rxfifosize / 1024, v / 16);
378 
379 	/* Attach the interface. */
380 	ether_ifattach(ifp, sc->sc_enaddr);
381 
382 	/*
383 	 * Tell the upper layer(s) we support long frames/checksum offloads.
384 	 */
385 	ifp->if_hdrlen = sizeof(struct ether_vlan_header);
386 	ifp->if_capabilities |= IFCAP_VLAN_MTU | IFCAP_HWCSUM;
387 	ifp->if_hwassist |= sc->sc_csum_features;
388 	ifp->if_capenable |= IFCAP_VLAN_MTU | IFCAP_HWCSUM;
389 
390 	return (0);
391 
392 	/*
393 	 * Free any resources we've allocated during the failed attach
394 	 * attempt.  Do this in reverse order and fall through.
395 	 */
396  fail_rxd:
397 	for (i = 0; i < GEM_NRXDESC; i++)
398 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
399 			bus_dmamap_destroy(sc->sc_rdmatag,
400 			    sc->sc_rxsoft[i].rxs_dmamap);
401  fail_txd:
402 	for (i = 0; i < GEM_TXQUEUELEN; i++)
403 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
404 			bus_dmamap_destroy(sc->sc_tdmatag,
405 			    sc->sc_txsoft[i].txs_dmamap);
406 	bus_dmamap_unload(sc->sc_cdmatag, sc->sc_cddmamap);
407  fail_cmem:
408 	bus_dmamem_free(sc->sc_cdmatag, sc->sc_control_data,
409 	    sc->sc_cddmamap);
410  fail_ctag:
411 	bus_dma_tag_destroy(sc->sc_cdmatag);
412  fail_ttag:
413 	bus_dma_tag_destroy(sc->sc_tdmatag);
414  fail_rtag:
415 	bus_dma_tag_destroy(sc->sc_rdmatag);
416  fail_ptag:
417 	bus_dma_tag_destroy(sc->sc_pdmatag);
418  fail_ifnet:
419 	if_free(ifp);
420 	return (error);
421 }
422 
423 void
424 gem_detach(struct gem_softc *sc)
425 {
426 	struct ifnet *ifp = sc->sc_ifp;
427 	int i;
428 
429 	ether_ifdetach(ifp);
430 	GEM_LOCK(sc);
431 	gem_stop(ifp, 1);
432 	GEM_UNLOCK(sc);
433 	callout_drain(&sc->sc_tick_ch);
434 #ifdef GEM_RINT_TIMEOUT
435 	callout_drain(&sc->sc_rx_ch);
436 #endif
437 	if_free(ifp);
438 	device_delete_child(sc->sc_dev, sc->sc_miibus);
439 
440 	for (i = 0; i < GEM_NRXDESC; i++)
441 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
442 			bus_dmamap_destroy(sc->sc_rdmatag,
443 			    sc->sc_rxsoft[i].rxs_dmamap);
444 	for (i = 0; i < GEM_TXQUEUELEN; i++)
445 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
446 			bus_dmamap_destroy(sc->sc_tdmatag,
447 			    sc->sc_txsoft[i].txs_dmamap);
448 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
449 	bus_dmamap_unload(sc->sc_cdmatag, sc->sc_cddmamap);
450 	bus_dmamem_free(sc->sc_cdmatag, sc->sc_control_data,
451 	    sc->sc_cddmamap);
452 	bus_dma_tag_destroy(sc->sc_cdmatag);
453 	bus_dma_tag_destroy(sc->sc_tdmatag);
454 	bus_dma_tag_destroy(sc->sc_rdmatag);
455 	bus_dma_tag_destroy(sc->sc_pdmatag);
456 }
457 
458 void
459 gem_suspend(struct gem_softc *sc)
460 {
461 	struct ifnet *ifp = sc->sc_ifp;
462 
463 	GEM_LOCK(sc);
464 	gem_stop(ifp, 0);
465 	GEM_UNLOCK(sc);
466 }
467 
468 void
469 gem_resume(struct gem_softc *sc)
470 {
471 	struct ifnet *ifp = sc->sc_ifp;
472 
473 	GEM_LOCK(sc);
474 	/*
475 	 * On resume all registers have to be initialized again like
476 	 * after power-on.
477 	 */
478 	sc->sc_flags &= ~GEM_INITED;
479 	if (ifp->if_flags & IFF_UP)
480 		gem_init_locked(sc);
481 	GEM_UNLOCK(sc);
482 }
483 
484 static inline void
485 gem_rxcksum(struct mbuf *m, uint64_t flags)
486 {
487 	struct ether_header *eh;
488 	struct ip *ip;
489 	struct udphdr *uh;
490 	uint16_t *opts;
491 	int32_t hlen, len, pktlen;
492 	uint32_t temp32;
493 	uint16_t cksum;
494 
495 	pktlen = m->m_pkthdr.len;
496 	if (pktlen < sizeof(struct ether_header) + sizeof(struct ip))
497 		return;
498 	eh = mtod(m, struct ether_header *);
499 	if (eh->ether_type != htons(ETHERTYPE_IP))
500 		return;
501 	ip = (struct ip *)(eh + 1);
502 	if (ip->ip_v != IPVERSION)
503 		return;
504 
505 	hlen = ip->ip_hl << 2;
506 	pktlen -= sizeof(struct ether_header);
507 	if (hlen < sizeof(struct ip))
508 		return;
509 	if (ntohs(ip->ip_len) < hlen)
510 		return;
511 	if (ntohs(ip->ip_len) != pktlen)
512 		return;
513 	if (ip->ip_off & htons(IP_MF | IP_OFFMASK))
514 		return;	/* Cannot handle fragmented packet. */
515 
516 	switch (ip->ip_p) {
517 	case IPPROTO_TCP:
518 		if (pktlen < (hlen + sizeof(struct tcphdr)))
519 			return;
520 		break;
521 	case IPPROTO_UDP:
522 		if (pktlen < (hlen + sizeof(struct udphdr)))
523 			return;
524 		uh = (struct udphdr *)((uint8_t *)ip + hlen);
525 		if (uh->uh_sum == 0)
526 			return; /* no checksum */
527 		break;
528 	default:
529 		return;
530 	}
531 
532 	cksum = ~(flags & GEM_RD_CHECKSUM);
533 	/* checksum fixup for IP options */
534 	len = hlen - sizeof(struct ip);
535 	if (len > 0) {
536 		opts = (uint16_t *)(ip + 1);
537 		for (; len > 0; len -= sizeof(uint16_t), opts++) {
538 			temp32 = cksum - *opts;
539 			temp32 = (temp32 >> 16) + (temp32 & 65535);
540 			cksum = temp32 & 65535;
541 		}
542 	}
543 	m->m_pkthdr.csum_flags |= CSUM_DATA_VALID;
544 	m->m_pkthdr.csum_data = cksum;
545 }
546 
547 static void
548 gem_cddma_callback(void *xsc, bus_dma_segment_t *segs, int nsegs, int error)
549 {
550 	struct gem_softc *sc = xsc;
551 
552 	if (error != 0)
553 		return;
554 	if (nsegs != 1)
555 		panic("%s: bad control buffer segment count", __func__);
556 	sc->sc_cddma = segs[0].ds_addr;
557 }
558 
559 static void
560 gem_tick(void *arg)
561 {
562 	struct gem_softc *sc = arg;
563 	struct ifnet *ifp = sc->sc_ifp;
564 	uint32_t v;
565 
566 	GEM_LOCK_ASSERT(sc, MA_OWNED);
567 
568 	/*
569 	 * Unload collision and error counters.
570 	 */
571 	if_inc_counter(ifp, IFCOUNTER_COLLISIONS,
572 	    GEM_BANK1_READ_4(sc, GEM_MAC_NORM_COLL_CNT) +
573 	    GEM_BANK1_READ_4(sc, GEM_MAC_FIRST_COLL_CNT));
574 	v = GEM_BANK1_READ_4(sc, GEM_MAC_EXCESS_COLL_CNT) +
575 	    GEM_BANK1_READ_4(sc, GEM_MAC_LATE_COLL_CNT);
576 	if_inc_counter(ifp, IFCOUNTER_COLLISIONS, v);
577 	if_inc_counter(ifp, IFCOUNTER_OERRORS, v);
578 	if_inc_counter(ifp, IFCOUNTER_IERRORS,
579 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_LEN_ERR_CNT) +
580 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_ALIGN_ERR) +
581 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CRC_ERR_CNT) +
582 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CODE_VIOL));
583 
584 	/*
585 	 * Then clear the hardware counters.
586 	 */
587 	GEM_BANK1_WRITE_4(sc, GEM_MAC_NORM_COLL_CNT, 0);
588 	GEM_BANK1_WRITE_4(sc, GEM_MAC_FIRST_COLL_CNT, 0);
589 	GEM_BANK1_WRITE_4(sc, GEM_MAC_EXCESS_COLL_CNT, 0);
590 	GEM_BANK1_WRITE_4(sc, GEM_MAC_LATE_COLL_CNT, 0);
591 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_LEN_ERR_CNT, 0);
592 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_ALIGN_ERR, 0);
593 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CRC_ERR_CNT, 0);
594 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CODE_VIOL, 0);
595 
596 	mii_tick(sc->sc_mii);
597 
598 	if (gem_watchdog(sc) == EJUSTRETURN)
599 		return;
600 
601 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
602 }
603 
604 static int
605 gem_bitwait(struct gem_softc *sc, u_int bank, bus_addr_t r, uint32_t clr,
606     uint32_t set)
607 {
608 	int i;
609 	uint32_t reg;
610 
611 	for (i = GEM_TRIES; i--; DELAY(100)) {
612 		reg = GEM_BANKN_READ_M(bank, 4, sc, r);
613 		if ((reg & clr) == 0 && (reg & set) == set)
614 			return (1);
615 	}
616 	return (0);
617 }
618 
619 static void
620 gem_reset(struct gem_softc *sc)
621 {
622 
623 #ifdef GEM_DEBUG
624 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
625 #endif
626 	gem_reset_rx(sc);
627 	gem_reset_tx(sc);
628 
629 	/* Do a full reset. */
630 	GEM_BANK2_WRITE_4(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX |
631 	    (sc->sc_variant == GEM_SUN_ERI ? GEM_ERI_CACHE_LINE_SIZE <<
632 	    GEM_RESET_CLSZ_SHFT : 0));
633 	GEM_BANK2_BARRIER(sc, GEM_RESET, 4,
634 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
635 	if (!GEM_BANK2_BITWAIT(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX, 0))
636 		device_printf(sc->sc_dev, "cannot reset device\n");
637 }
638 
639 static void
640 gem_rxdrain(struct gem_softc *sc)
641 {
642 	struct gem_rxsoft *rxs;
643 	int i;
644 
645 	for (i = 0; i < GEM_NRXDESC; i++) {
646 		rxs = &sc->sc_rxsoft[i];
647 		if (rxs->rxs_mbuf != NULL) {
648 			bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
649 			    BUS_DMASYNC_POSTREAD);
650 			bus_dmamap_unload(sc->sc_rdmatag, rxs->rxs_dmamap);
651 			m_freem(rxs->rxs_mbuf);
652 			rxs->rxs_mbuf = NULL;
653 		}
654 	}
655 }
656 
657 static void
658 gem_stop(struct ifnet *ifp, int disable)
659 {
660 	struct gem_softc *sc = ifp->if_softc;
661 	struct gem_txsoft *txs;
662 
663 #ifdef GEM_DEBUG
664 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
665 #endif
666 
667 	callout_stop(&sc->sc_tick_ch);
668 #ifdef GEM_RINT_TIMEOUT
669 	callout_stop(&sc->sc_rx_ch);
670 #endif
671 
672 	gem_reset_tx(sc);
673 	gem_reset_rx(sc);
674 
675 	/*
676 	 * Release any queued transmit buffers.
677 	 */
678 	while ((txs = STAILQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
679 		STAILQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
680 		if (txs->txs_ndescs != 0) {
681 			bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
682 			    BUS_DMASYNC_POSTWRITE);
683 			bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
684 			if (txs->txs_mbuf != NULL) {
685 				m_freem(txs->txs_mbuf);
686 				txs->txs_mbuf = NULL;
687 			}
688 		}
689 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
690 	}
691 
692 	if (disable)
693 		gem_rxdrain(sc);
694 
695 	/*
696 	 * Mark the interface down and cancel the watchdog timer.
697 	 */
698 	ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
699 	sc->sc_flags &= ~GEM_LINK;
700 	sc->sc_wdog_timer = 0;
701 }
702 
703 static int
704 gem_reset_rx(struct gem_softc *sc)
705 {
706 
707 	/*
708 	 * Resetting while DMA is in progress can cause a bus hang, so we
709 	 * disable DMA first.
710 	 */
711 	(void)gem_disable_rx(sc);
712 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG, 0);
713 	GEM_BANK1_BARRIER(sc, GEM_RX_CONFIG, 4,
714 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
715 	if (!GEM_BANK1_BITWAIT(sc, GEM_RX_CONFIG, GEM_RX_CONFIG_RXDMA_EN, 0))
716 		device_printf(sc->sc_dev, "cannot disable RX DMA\n");
717 
718 	/* Wait 5ms extra. */
719 	DELAY(5000);
720 
721 	/* Reset the ERX. */
722 	GEM_BANK2_WRITE_4(sc, GEM_RESET, GEM_RESET_RX |
723 	    (sc->sc_variant == GEM_SUN_ERI ? GEM_ERI_CACHE_LINE_SIZE <<
724 	    GEM_RESET_CLSZ_SHFT : 0));
725 	GEM_BANK2_BARRIER(sc, GEM_RESET, 4,
726 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
727 	if (!GEM_BANK2_BITWAIT(sc, GEM_RESET, GEM_RESET_RX, 0)) {
728 		device_printf(sc->sc_dev, "cannot reset receiver\n");
729 		return (1);
730 	}
731 
732 	/* Finally, reset RX MAC. */
733 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RXRESET, 1);
734 	GEM_BANK1_BARRIER(sc, GEM_MAC_RXRESET, 4,
735 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
736 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_RXRESET, 1, 0)) {
737 		device_printf(sc->sc_dev, "cannot reset RX MAC\n");
738 		return (1);
739 	}
740 
741 	return (0);
742 }
743 
744 /*
745  * Reset the receiver DMA engine.
746  *
747  * Intended to be used in case of GEM_INTR_RX_TAG_ERR, GEM_MAC_RX_OVERFLOW
748  * etc in order to reset the receiver DMA engine only and not do a full
749  * reset which amongst others also downs the link and clears the FIFOs.
750  */
751 static void
752 gem_reset_rxdma(struct gem_softc *sc)
753 {
754 	int i;
755 
756 	if (gem_reset_rx(sc) != 0) {
757 		sc->sc_ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
758 		return (gem_init_locked(sc));
759 	}
760 	for (i = 0; i < GEM_NRXDESC; i++)
761 		if (sc->sc_rxsoft[i].rxs_mbuf != NULL)
762 			GEM_UPDATE_RXDESC(sc, i);
763 	sc->sc_rxptr = 0;
764 	GEM_CDSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
765 
766 	/* NOTE: we use only 32-bit DMA addresses here. */
767 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_HI, 0);
768 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_LO, GEM_CDRXADDR(sc, 0));
769 	GEM_BANK1_WRITE_4(sc, GEM_RX_KICK, GEM_NRXDESC - 4);
770 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG,
771 	    gem_ringsize(GEM_NRXDESC /* XXX */) |
772 	    ((ETHER_HDR_LEN + sizeof(struct ip)) <<
773 	    GEM_RX_CONFIG_CXM_START_SHFT) |
774 	    (GEM_THRSH_1024 << GEM_RX_CONFIG_FIFO_THRS_SHIFT) |
775 	    (ETHER_ALIGN << GEM_RX_CONFIG_FBOFF_SHFT));
776 	/* Adjusting for the SBus clock probably isn't worth the fuzz. */
777 	GEM_BANK1_WRITE_4(sc, GEM_RX_BLANKING,
778 	    ((6 * (sc->sc_flags & GEM_PCI66) != 0 ? 2 : 1) <<
779 	    GEM_RX_BLANKING_TIME_SHIFT) | 6);
780 	GEM_BANK1_WRITE_4(sc, GEM_RX_PAUSE_THRESH,
781 	    (3 * sc->sc_rxfifosize / 256) |
782 	    ((sc->sc_rxfifosize / 256) << 12));
783 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG,
784 	    GEM_BANK1_READ_4(sc, GEM_RX_CONFIG) | GEM_RX_CONFIG_RXDMA_EN);
785 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_MASK,
786 	    GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT);
787 	/*
788 	 * Clear the RX filter and reprogram it.  This will also set the
789 	 * current RX MAC configuration and enable it.
790 	 */
791 	gem_setladrf(sc);
792 }
793 
794 static int
795 gem_reset_tx(struct gem_softc *sc)
796 {
797 
798 	/*
799 	 * Resetting while DMA is in progress can cause a bus hang, so we
800 	 * disable DMA first.
801 	 */
802 	(void)gem_disable_tx(sc);
803 	GEM_BANK1_WRITE_4(sc, GEM_TX_CONFIG, 0);
804 	GEM_BANK1_BARRIER(sc, GEM_TX_CONFIG, 4,
805 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
806 	if (!GEM_BANK1_BITWAIT(sc, GEM_TX_CONFIG, GEM_TX_CONFIG_TXDMA_EN, 0))
807 		device_printf(sc->sc_dev, "cannot disable TX DMA\n");
808 
809 	/* Wait 5ms extra. */
810 	DELAY(5000);
811 
812 	/* Finally, reset the ETX. */
813 	GEM_BANK2_WRITE_4(sc, GEM_RESET, GEM_RESET_TX |
814 	    (sc->sc_variant == GEM_SUN_ERI ? GEM_ERI_CACHE_LINE_SIZE <<
815 	    GEM_RESET_CLSZ_SHFT : 0));
816 	GEM_BANK2_BARRIER(sc, GEM_RESET, 4,
817 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
818 	if (!GEM_BANK2_BITWAIT(sc, GEM_RESET, GEM_RESET_TX, 0)) {
819 		device_printf(sc->sc_dev, "cannot reset transmitter\n");
820 		return (1);
821 	}
822 	return (0);
823 }
824 
825 static int
826 gem_disable_rx(struct gem_softc *sc)
827 {
828 
829 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG,
830 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG) & ~GEM_MAC_RX_ENABLE);
831 	GEM_BANK1_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
832 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
833 	if (GEM_BANK1_BITWAIT(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_ENABLE, 0))
834 		return (1);
835 	device_printf(sc->sc_dev, "cannot disable RX MAC\n");
836 	return (0);
837 }
838 
839 static int
840 gem_disable_tx(struct gem_softc *sc)
841 {
842 
843 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG,
844 	    GEM_BANK1_READ_4(sc, GEM_MAC_TX_CONFIG) & ~GEM_MAC_TX_ENABLE);
845 	GEM_BANK1_BARRIER(sc, GEM_MAC_TX_CONFIG, 4,
846 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
847 	if (GEM_BANK1_BITWAIT(sc, GEM_MAC_TX_CONFIG, GEM_MAC_TX_ENABLE, 0))
848 		return (1);
849 	device_printf(sc->sc_dev, "cannot disable TX MAC\n");
850 	return (0);
851 }
852 
853 static int
854 gem_meminit(struct gem_softc *sc)
855 {
856 	struct gem_rxsoft *rxs;
857 	int error, i;
858 
859 	GEM_LOCK_ASSERT(sc, MA_OWNED);
860 
861 	/*
862 	 * Initialize the transmit descriptor ring.
863 	 */
864 	for (i = 0; i < GEM_NTXDESC; i++) {
865 		sc->sc_txdescs[i].gd_flags = 0;
866 		sc->sc_txdescs[i].gd_addr = 0;
867 	}
868 	sc->sc_txfree = GEM_MAXTXFREE;
869 	sc->sc_txnext = 0;
870 	sc->sc_txwin = 0;
871 
872 	/*
873 	 * Initialize the receive descriptor and receive job
874 	 * descriptor rings.
875 	 */
876 	for (i = 0; i < GEM_NRXDESC; i++) {
877 		rxs = &sc->sc_rxsoft[i];
878 		if (rxs->rxs_mbuf == NULL) {
879 			if ((error = gem_add_rxbuf(sc, i)) != 0) {
880 				device_printf(sc->sc_dev,
881 				    "unable to allocate or map RX buffer %d, "
882 				    "error = %d\n", i, error);
883 				/*
884 				 * XXX we should attempt to run with fewer
885 				 * receive buffers instead of just failing.
886 				 */
887 				gem_rxdrain(sc);
888 				return (1);
889 			}
890 		} else
891 			GEM_INIT_RXDESC(sc, i);
892 	}
893 	sc->sc_rxptr = 0;
894 
895 	GEM_CDSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
896 
897 	return (0);
898 }
899 
900 static u_int
901 gem_ringsize(u_int sz)
902 {
903 
904 	switch (sz) {
905 	case 32:
906 		return (GEM_RING_SZ_32);
907 	case 64:
908 		return (GEM_RING_SZ_64);
909 	case 128:
910 		return (GEM_RING_SZ_128);
911 	case 256:
912 		return (GEM_RING_SZ_256);
913 	case 512:
914 		return (GEM_RING_SZ_512);
915 	case 1024:
916 		return (GEM_RING_SZ_1024);
917 	case 2048:
918 		return (GEM_RING_SZ_2048);
919 	case 4096:
920 		return (GEM_RING_SZ_4096);
921 	case 8192:
922 		return (GEM_RING_SZ_8192);
923 	default:
924 		printf("%s: invalid ring size %d\n", __func__, sz);
925 		return (GEM_RING_SZ_32);
926 	}
927 }
928 
929 static void
930 gem_init(void *xsc)
931 {
932 	struct gem_softc *sc = xsc;
933 
934 	GEM_LOCK(sc);
935 	gem_init_locked(sc);
936 	GEM_UNLOCK(sc);
937 }
938 
939 /*
940  * Initialization of interface; set up initialization block
941  * and transmit/receive descriptor rings.
942  */
943 static void
944 gem_init_locked(struct gem_softc *sc)
945 {
946 	struct ifnet *ifp = sc->sc_ifp;
947 	uint32_t v;
948 
949 	GEM_LOCK_ASSERT(sc, MA_OWNED);
950 
951 	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
952 		return;
953 
954 #ifdef GEM_DEBUG
955 	CTR2(KTR_GEM, "%s: %s: calling stop", device_get_name(sc->sc_dev),
956 	    __func__);
957 #endif
958 	/*
959 	 * Initialization sequence.  The numbered steps below correspond
960 	 * to the sequence outlined in section 6.3.5.1 in the Ethernet
961 	 * Channel Engine manual (part of the PCIO manual).
962 	 * See also the STP2002-STQ document from Sun Microsystems.
963 	 */
964 
965 	/* step 1 & 2.  Reset the Ethernet Channel. */
966 	gem_stop(ifp, 0);
967 	gem_reset(sc);
968 #ifdef GEM_DEBUG
969 	CTR2(KTR_GEM, "%s: %s: restarting", device_get_name(sc->sc_dev),
970 	    __func__);
971 #endif
972 
973 	if ((sc->sc_flags & GEM_SERDES) == 0)
974 		/* Re-initialize the MIF. */
975 		gem_mifinit(sc);
976 
977 	/* step 3.  Setup data structures in host memory. */
978 	if (gem_meminit(sc) != 0)
979 		return;
980 
981 	/* step 4.  TX MAC registers & counters */
982 	gem_init_regs(sc);
983 
984 	/* step 5.  RX MAC registers & counters */
985 
986 	/* step 6 & 7.  Program Descriptor Ring Base Addresses. */
987 	/* NOTE: we use only 32-bit DMA addresses here. */
988 	GEM_BANK1_WRITE_4(sc, GEM_TX_RING_PTR_HI, 0);
989 	GEM_BANK1_WRITE_4(sc, GEM_TX_RING_PTR_LO, GEM_CDTXADDR(sc, 0));
990 
991 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_HI, 0);
992 	GEM_BANK1_WRITE_4(sc, GEM_RX_RING_PTR_LO, GEM_CDRXADDR(sc, 0));
993 #ifdef GEM_DEBUG
994 	CTR3(KTR_GEM, "loading RX ring %lx, TX ring %lx, cddma %lx",
995 	    GEM_CDRXADDR(sc, 0), GEM_CDTXADDR(sc, 0), sc->sc_cddma);
996 #endif
997 
998 	/* step 8.  Global Configuration & Interrupt Mask */
999 
1000 	/*
1001 	 * Set the internal arbitration to "infinite" bursts of the
1002 	 * maximum length of 31 * 64 bytes so DMA transfers aren't
1003 	 * split up in cache line size chunks.  This greatly improves
1004 	 * RX performance.
1005 	 * Enable silicon bug workarounds for the Apple variants.
1006 	 */
1007 	GEM_BANK1_WRITE_4(sc, GEM_CONFIG,
1008 	    GEM_CONFIG_TXDMA_LIMIT | GEM_CONFIG_RXDMA_LIMIT |
1009 	    ((sc->sc_flags & GEM_PCI) != 0 ? GEM_CONFIG_BURST_INF :
1010 	    GEM_CONFIG_BURST_64) | (GEM_IS_APPLE(sc) ?
1011 	    GEM_CONFIG_RONPAULBIT | GEM_CONFIG_BUG2FIX : 0));
1012 
1013 	GEM_BANK1_WRITE_4(sc, GEM_INTMASK,
1014 	    ~(GEM_INTR_TX_INTME | GEM_INTR_TX_EMPTY | GEM_INTR_RX_DONE |
1015 	    GEM_INTR_RX_NOBUF | GEM_INTR_RX_TAG_ERR | GEM_INTR_PERR |
1016 	    GEM_INTR_BERR
1017 #ifdef GEM_DEBUG
1018 	    | GEM_INTR_PCS | GEM_INTR_MIF
1019 #endif
1020 	    ));
1021 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_MASK,
1022 	    GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT);
1023 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_MASK,
1024 	    GEM_MAC_TX_XMIT_DONE | GEM_MAC_TX_DEFER_EXP |
1025 	    GEM_MAC_TX_PEAK_EXP);
1026 #ifdef GEM_DEBUG
1027 	GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_MASK,
1028 	    ~(GEM_MAC_PAUSED | GEM_MAC_PAUSE | GEM_MAC_RESUME));
1029 #else
1030 	GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_MASK,
1031 	    GEM_MAC_PAUSED | GEM_MAC_PAUSE | GEM_MAC_RESUME);
1032 #endif
1033 
1034 	/* step 9.  ETX Configuration: use mostly default values. */
1035 
1036 	/* Enable DMA. */
1037 	v = gem_ringsize(GEM_NTXDESC);
1038 	/* Set TX FIFO threshold and enable DMA. */
1039 	v |= ((sc->sc_variant == GEM_SUN_ERI ? 0x100 : 0x4ff) << 10) &
1040 	    GEM_TX_CONFIG_TXFIFO_TH;
1041 	GEM_BANK1_WRITE_4(sc, GEM_TX_CONFIG, v | GEM_TX_CONFIG_TXDMA_EN);
1042 
1043 	/* step 10.  ERX Configuration */
1044 
1045 	/* Encode Receive Descriptor ring size. */
1046 	v = gem_ringsize(GEM_NRXDESC /* XXX */);
1047 	/* RX TCP/UDP checksum offset */
1048 	v |= ((ETHER_HDR_LEN + sizeof(struct ip)) <<
1049 	    GEM_RX_CONFIG_CXM_START_SHFT);
1050 	/* Set RX FIFO threshold, set first byte offset and enable DMA. */
1051 	GEM_BANK1_WRITE_4(sc, GEM_RX_CONFIG,
1052 	    v | (GEM_THRSH_1024 << GEM_RX_CONFIG_FIFO_THRS_SHIFT) |
1053 	    (ETHER_ALIGN << GEM_RX_CONFIG_FBOFF_SHFT) |
1054 	    GEM_RX_CONFIG_RXDMA_EN);
1055 
1056 	/* Adjusting for the SBus clock probably isn't worth the fuzz. */
1057 	GEM_BANK1_WRITE_4(sc, GEM_RX_BLANKING,
1058 	    ((6 * (sc->sc_flags & GEM_PCI66) != 0 ? 2 : 1) <<
1059 	    GEM_RX_BLANKING_TIME_SHIFT) | 6);
1060 
1061 	/*
1062 	 * The following value is for an OFF Threshold of about 3/4 full
1063 	 * and an ON Threshold of 1/4 full.
1064 	 */
1065 	GEM_BANK1_WRITE_4(sc, GEM_RX_PAUSE_THRESH,
1066 	    (3 * sc->sc_rxfifosize / 256) |
1067 	    ((sc->sc_rxfifosize / 256) << 12));
1068 
1069 	/* step 11.  Configure Media. */
1070 
1071 	/* step 12.  RX_MAC Configuration Register */
1072 	v = GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG);
1073 	v &= ~GEM_MAC_RX_ENABLE;
1074 	v |= GEM_MAC_RX_STRIP_CRC;
1075 	sc->sc_mac_rxcfg = v;
1076 	/*
1077 	 * Clear the RX filter and reprogram it.  This will also set the
1078 	 * current RX MAC configuration and enable it.
1079 	 */
1080 	gem_setladrf(sc);
1081 
1082 	/* step 13.  TX_MAC Configuration Register */
1083 	v = GEM_BANK1_READ_4(sc, GEM_MAC_TX_CONFIG);
1084 	v |= GEM_MAC_TX_ENABLE;
1085 	(void)gem_disable_tx(sc);
1086 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG, v);
1087 
1088 	/* step 14.  Issue Transmit Pending command. */
1089 
1090 	/* step 15.  Give the receiver a swift kick. */
1091 	GEM_BANK1_WRITE_4(sc, GEM_RX_KICK, GEM_NRXDESC - 4);
1092 
1093 	ifp->if_drv_flags |= IFF_DRV_RUNNING;
1094 	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
1095 
1096 	mii_mediachg(sc->sc_mii);
1097 
1098 	/* Start the one second timer. */
1099 	sc->sc_wdog_timer = 0;
1100 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
1101 }
1102 
1103 static int
1104 gem_load_txmbuf(struct gem_softc *sc, struct mbuf **m_head)
1105 {
1106 	bus_dma_segment_t txsegs[GEM_NTXSEGS];
1107 	struct gem_txsoft *txs;
1108 	struct ip *ip;
1109 	struct mbuf *m;
1110 	uint64_t cflags, flags;
1111 	int error, nexttx, nsegs, offset, seg;
1112 
1113 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1114 
1115 	/* Get a work queue entry. */
1116 	if ((txs = STAILQ_FIRST(&sc->sc_txfreeq)) == NULL) {
1117 		/* Ran out of descriptors. */
1118 		return (ENOBUFS);
1119 	}
1120 
1121 	cflags = 0;
1122 	if (((*m_head)->m_pkthdr.csum_flags & sc->sc_csum_features) != 0) {
1123 		if (M_WRITABLE(*m_head) == 0) {
1124 			m = m_dup(*m_head, M_NOWAIT);
1125 			m_freem(*m_head);
1126 			*m_head = m;
1127 			if (m == NULL)
1128 				return (ENOBUFS);
1129 		}
1130 		offset = sizeof(struct ether_header);
1131 		m = m_pullup(*m_head, offset + sizeof(struct ip));
1132 		if (m == NULL) {
1133 			*m_head = NULL;
1134 			return (ENOBUFS);
1135 		}
1136 		ip = (struct ip *)(mtod(m, caddr_t) + offset);
1137 		offset += (ip->ip_hl << 2);
1138 		cflags = offset << GEM_TD_CXSUM_STARTSHFT |
1139 		    ((offset + m->m_pkthdr.csum_data) <<
1140 		    GEM_TD_CXSUM_STUFFSHFT) | GEM_TD_CXSUM_ENABLE;
1141 		*m_head = m;
1142 	}
1143 
1144 	error = bus_dmamap_load_mbuf_sg(sc->sc_tdmatag, txs->txs_dmamap,
1145 	    *m_head, txsegs, &nsegs, BUS_DMA_NOWAIT);
1146 	if (error == EFBIG) {
1147 		m = m_collapse(*m_head, M_NOWAIT, GEM_NTXSEGS);
1148 		if (m == NULL) {
1149 			m_freem(*m_head);
1150 			*m_head = NULL;
1151 			return (ENOBUFS);
1152 		}
1153 		*m_head = m;
1154 		error = bus_dmamap_load_mbuf_sg(sc->sc_tdmatag,
1155 		    txs->txs_dmamap, *m_head, txsegs, &nsegs,
1156 		    BUS_DMA_NOWAIT);
1157 		if (error != 0) {
1158 			m_freem(*m_head);
1159 			*m_head = NULL;
1160 			return (error);
1161 		}
1162 	} else if (error != 0)
1163 		return (error);
1164 	/* If nsegs is wrong then the stack is corrupt. */
1165 	KASSERT(nsegs <= GEM_NTXSEGS,
1166 	    ("%s: too many DMA segments (%d)", __func__, nsegs));
1167 	if (nsegs == 0) {
1168 		m_freem(*m_head);
1169 		*m_head = NULL;
1170 		return (EIO);
1171 	}
1172 
1173 	/*
1174 	 * Ensure we have enough descriptors free to describe
1175 	 * the packet.  Note, we always reserve one descriptor
1176 	 * at the end of the ring as a termination point, in
1177 	 * order to prevent wrap-around.
1178 	 */
1179 	if (nsegs > sc->sc_txfree - 1) {
1180 		txs->txs_ndescs = 0;
1181 		bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
1182 		return (ENOBUFS);
1183 	}
1184 
1185 	txs->txs_ndescs = nsegs;
1186 	txs->txs_firstdesc = sc->sc_txnext;
1187 	nexttx = txs->txs_firstdesc;
1188 	for (seg = 0; seg < nsegs; seg++, nexttx = GEM_NEXTTX(nexttx)) {
1189 #ifdef GEM_DEBUG
1190 		CTR6(KTR_GEM,
1191 		    "%s: mapping seg %d (txd %d), len %lx, addr %#lx (%#lx)",
1192 		    __func__, seg, nexttx, txsegs[seg].ds_len,
1193 		    txsegs[seg].ds_addr,
1194 		    GEM_DMA_WRITE(sc, txsegs[seg].ds_addr));
1195 #endif
1196 		sc->sc_txdescs[nexttx].gd_addr =
1197 		    GEM_DMA_WRITE(sc, txsegs[seg].ds_addr);
1198 		KASSERT(txsegs[seg].ds_len < GEM_TD_BUFSIZE,
1199 		    ("%s: segment size too large!", __func__));
1200 		flags = txsegs[seg].ds_len & GEM_TD_BUFSIZE;
1201 		sc->sc_txdescs[nexttx].gd_flags =
1202 		    GEM_DMA_WRITE(sc, flags | cflags);
1203 		txs->txs_lastdesc = nexttx;
1204 	}
1205 
1206 	/* Set EOP on the last descriptor. */
1207 #ifdef GEM_DEBUG
1208 	CTR3(KTR_GEM, "%s: end of packet at segment %d, TX %d",
1209 	    __func__, seg, nexttx);
1210 #endif
1211 	sc->sc_txdescs[txs->txs_lastdesc].gd_flags |=
1212 	    GEM_DMA_WRITE(sc, GEM_TD_END_OF_PACKET);
1213 
1214 	/* Lastly set SOP on the first descriptor. */
1215 #ifdef GEM_DEBUG
1216 	CTR3(KTR_GEM, "%s: start of packet at segment %d, TX %d",
1217 	    __func__, seg, nexttx);
1218 #endif
1219 	if (++sc->sc_txwin > GEM_NTXSEGS * 2 / 3) {
1220 		sc->sc_txwin = 0;
1221 		sc->sc_txdescs[txs->txs_firstdesc].gd_flags |=
1222 		    GEM_DMA_WRITE(sc, GEM_TD_INTERRUPT_ME |
1223 		    GEM_TD_START_OF_PACKET);
1224 	} else
1225 		sc->sc_txdescs[txs->txs_firstdesc].gd_flags |=
1226 		    GEM_DMA_WRITE(sc, GEM_TD_START_OF_PACKET);
1227 
1228 	/* Sync the DMA map. */
1229 	bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
1230 	    BUS_DMASYNC_PREWRITE);
1231 
1232 #ifdef GEM_DEBUG
1233 	CTR4(KTR_GEM, "%s: setting firstdesc=%d, lastdesc=%d, ndescs=%d",
1234 	    __func__, txs->txs_firstdesc, txs->txs_lastdesc,
1235 	    txs->txs_ndescs);
1236 #endif
1237 	STAILQ_REMOVE_HEAD(&sc->sc_txfreeq, txs_q);
1238 	STAILQ_INSERT_TAIL(&sc->sc_txdirtyq, txs, txs_q);
1239 	txs->txs_mbuf = *m_head;
1240 
1241 	sc->sc_txnext = GEM_NEXTTX(txs->txs_lastdesc);
1242 	sc->sc_txfree -= txs->txs_ndescs;
1243 
1244 	return (0);
1245 }
1246 
1247 static void
1248 gem_init_regs(struct gem_softc *sc)
1249 {
1250 	const u_char *laddr = IF_LLADDR(sc->sc_ifp);
1251 
1252 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1253 
1254 	/* These registers are not cleared on reset. */
1255 	if ((sc->sc_flags & GEM_INITED) == 0) {
1256 		/* magic values */
1257 		GEM_BANK1_WRITE_4(sc, GEM_MAC_IPG0, 0);
1258 		GEM_BANK1_WRITE_4(sc, GEM_MAC_IPG1, 8);
1259 		GEM_BANK1_WRITE_4(sc, GEM_MAC_IPG2, 4);
1260 
1261 		/* min frame length */
1262 		GEM_BANK1_WRITE_4(sc, GEM_MAC_MAC_MIN_FRAME, ETHER_MIN_LEN);
1263 		/* max frame length and max burst size */
1264 		GEM_BANK1_WRITE_4(sc, GEM_MAC_MAC_MAX_FRAME,
1265 		    (ETHER_MAX_LEN + ETHER_VLAN_ENCAP_LEN) | (0x2000 << 16));
1266 
1267 		/* more magic values */
1268 		GEM_BANK1_WRITE_4(sc, GEM_MAC_PREAMBLE_LEN, 0x7);
1269 		GEM_BANK1_WRITE_4(sc, GEM_MAC_JAM_SIZE, 0x4);
1270 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ATTEMPT_LIMIT, 0x10);
1271 		GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_TYPE, 0x8808);
1272 
1273 		/* random number seed */
1274 		GEM_BANK1_WRITE_4(sc, GEM_MAC_RANDOM_SEED,
1275 		    ((laddr[5] << 8) | laddr[4]) & 0x3ff);
1276 
1277 		/* secondary MAC address: 0:0:0:0:0:0 */
1278 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR3, 0);
1279 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR4, 0);
1280 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR5, 0);
1281 
1282 		/* MAC control address: 01:80:c2:00:00:01 */
1283 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR6, 0x0001);
1284 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR7, 0xc200);
1285 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR8, 0x0180);
1286 
1287 		/* MAC filter address: 0:0:0:0:0:0 */
1288 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR_FILTER0, 0);
1289 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR_FILTER1, 0);
1290 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR_FILTER2, 0);
1291 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADR_FLT_MASK1_2, 0);
1292 		GEM_BANK1_WRITE_4(sc, GEM_MAC_ADR_FLT_MASK0, 0);
1293 
1294 		sc->sc_flags |= GEM_INITED;
1295 	}
1296 
1297 	/* Counters need to be zeroed. */
1298 	GEM_BANK1_WRITE_4(sc, GEM_MAC_NORM_COLL_CNT, 0);
1299 	GEM_BANK1_WRITE_4(sc, GEM_MAC_FIRST_COLL_CNT, 0);
1300 	GEM_BANK1_WRITE_4(sc, GEM_MAC_EXCESS_COLL_CNT, 0);
1301 	GEM_BANK1_WRITE_4(sc, GEM_MAC_LATE_COLL_CNT, 0);
1302 	GEM_BANK1_WRITE_4(sc, GEM_MAC_DEFER_TMR_CNT, 0);
1303 	GEM_BANK1_WRITE_4(sc, GEM_MAC_PEAK_ATTEMPTS, 0);
1304 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_FRAME_COUNT, 0);
1305 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_LEN_ERR_CNT, 0);
1306 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_ALIGN_ERR, 0);
1307 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CRC_ERR_CNT, 0);
1308 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CODE_VIOL, 0);
1309 
1310 	/* Set XOFF PAUSE time. */
1311 	GEM_BANK1_WRITE_4(sc, GEM_MAC_SEND_PAUSE_CMD, 0x1BF0);
1312 
1313 	/* Set the station address. */
1314 	GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR0, (laddr[4] << 8) | laddr[5]);
1315 	GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR1, (laddr[2] << 8) | laddr[3]);
1316 	GEM_BANK1_WRITE_4(sc, GEM_MAC_ADDR2, (laddr[0] << 8) | laddr[1]);
1317 
1318 	/* Enable MII outputs. */
1319 	GEM_BANK1_WRITE_4(sc, GEM_MAC_XIF_CONFIG, GEM_MAC_XIF_TX_MII_ENA);
1320 }
1321 
1322 static void
1323 gem_start(struct ifnet *ifp)
1324 {
1325 	struct gem_softc *sc = ifp->if_softc;
1326 
1327 	GEM_LOCK(sc);
1328 	gem_start_locked(ifp);
1329 	GEM_UNLOCK(sc);
1330 }
1331 
1332 static inline void
1333 gem_txkick(struct gem_softc *sc)
1334 {
1335 
1336 	/*
1337 	 * Update the TX kick register.  This register has to point to the
1338 	 * descriptor after the last valid one and for optimum performance
1339 	 * should be incremented in multiples of 4 (the DMA engine fetches/
1340 	 * updates descriptors in batches of 4).
1341 	 */
1342 #ifdef GEM_DEBUG
1343 	CTR3(KTR_GEM, "%s: %s: kicking TX %d",
1344 	    device_get_name(sc->sc_dev), __func__, sc->sc_txnext);
1345 #endif
1346 	GEM_CDSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1347 	GEM_BANK1_WRITE_4(sc, GEM_TX_KICK, sc->sc_txnext);
1348 }
1349 
1350 static void
1351 gem_start_locked(struct ifnet *ifp)
1352 {
1353 	struct gem_softc *sc = ifp->if_softc;
1354 	struct mbuf *m;
1355 	int kicked, ntx;
1356 
1357 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1358 
1359 	if ((ifp->if_drv_flags & (IFF_DRV_RUNNING | IFF_DRV_OACTIVE)) !=
1360 	    IFF_DRV_RUNNING || (sc->sc_flags & GEM_LINK) == 0)
1361 		return;
1362 
1363 #ifdef GEM_DEBUG
1364 	CTR4(KTR_GEM, "%s: %s: txfree %d, txnext %d",
1365 	    device_get_name(sc->sc_dev), __func__, sc->sc_txfree,
1366 	    sc->sc_txnext);
1367 #endif
1368 	ntx = 0;
1369 	kicked = 0;
1370 	for (; !IFQ_DRV_IS_EMPTY(&ifp->if_snd) && sc->sc_txfree > 1;) {
1371 		IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
1372 		if (m == NULL)
1373 			break;
1374 		if (gem_load_txmbuf(sc, &m) != 0) {
1375 			if (m == NULL)
1376 				break;
1377 			ifp->if_drv_flags |= IFF_DRV_OACTIVE;
1378 			IFQ_DRV_PREPEND(&ifp->if_snd, m);
1379 			break;
1380 		}
1381 		if ((sc->sc_txnext % 4) == 0) {
1382 			gem_txkick(sc);
1383 			kicked = 1;
1384 		} else
1385 			kicked = 0;
1386 		ntx++;
1387 		BPF_MTAP(ifp, m);
1388 	}
1389 
1390 	if (ntx > 0) {
1391 		if (kicked == 0)
1392 			gem_txkick(sc);
1393 #ifdef GEM_DEBUG
1394 		CTR2(KTR_GEM, "%s: packets enqueued, OWN on %d",
1395 		    device_get_name(sc->sc_dev), sc->sc_txnext);
1396 #endif
1397 
1398 		/* Set a watchdog timer in case the chip flakes out. */
1399 		sc->sc_wdog_timer = 5;
1400 #ifdef GEM_DEBUG
1401 		CTR3(KTR_GEM, "%s: %s: watchdog %d",
1402 		    device_get_name(sc->sc_dev), __func__,
1403 		    sc->sc_wdog_timer);
1404 #endif
1405 	}
1406 }
1407 
1408 static void
1409 gem_tint(struct gem_softc *sc)
1410 {
1411 	struct ifnet *ifp = sc->sc_ifp;
1412 	struct gem_txsoft *txs;
1413 	int progress;
1414 	uint32_t txlast;
1415 #ifdef GEM_DEBUG
1416 	int i;
1417 
1418 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1419 
1420 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
1421 #endif
1422 
1423 	/*
1424 	 * Go through our TX list and free mbufs for those
1425 	 * frames that have been transmitted.
1426 	 */
1427 	progress = 0;
1428 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD);
1429 	while ((txs = STAILQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
1430 #ifdef GEM_DEBUG
1431 		if ((ifp->if_flags & IFF_DEBUG) != 0) {
1432 			printf("    txsoft %p transmit chain:\n", txs);
1433 			for (i = txs->txs_firstdesc;; i = GEM_NEXTTX(i)) {
1434 				printf("descriptor %d: ", i);
1435 				printf("gd_flags: 0x%016llx\t",
1436 				    (long long)GEM_DMA_READ(sc,
1437 				    sc->sc_txdescs[i].gd_flags));
1438 				printf("gd_addr: 0x%016llx\n",
1439 				    (long long)GEM_DMA_READ(sc,
1440 				    sc->sc_txdescs[i].gd_addr));
1441 				if (i == txs->txs_lastdesc)
1442 					break;
1443 			}
1444 		}
1445 #endif
1446 
1447 		/*
1448 		 * In theory, we could harvest some descriptors before
1449 		 * the ring is empty, but that's a bit complicated.
1450 		 *
1451 		 * GEM_TX_COMPLETION points to the last descriptor
1452 		 * processed + 1.
1453 		 */
1454 		txlast = GEM_BANK1_READ_4(sc, GEM_TX_COMPLETION);
1455 #ifdef GEM_DEBUG
1456 		CTR4(KTR_GEM, "%s: txs->txs_firstdesc = %d, "
1457 		    "txs->txs_lastdesc = %d, txlast = %d",
1458 		    __func__, txs->txs_firstdesc, txs->txs_lastdesc, txlast);
1459 #endif
1460 		if (txs->txs_firstdesc <= txs->txs_lastdesc) {
1461 			if ((txlast >= txs->txs_firstdesc) &&
1462 			    (txlast <= txs->txs_lastdesc))
1463 				break;
1464 		} else {
1465 			/* Ick -- this command wraps. */
1466 			if ((txlast >= txs->txs_firstdesc) ||
1467 			    (txlast <= txs->txs_lastdesc))
1468 				break;
1469 		}
1470 
1471 #ifdef GEM_DEBUG
1472 		CTR1(KTR_GEM, "%s: releasing a descriptor", __func__);
1473 #endif
1474 		STAILQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
1475 
1476 		sc->sc_txfree += txs->txs_ndescs;
1477 
1478 		bus_dmamap_sync(sc->sc_tdmatag, txs->txs_dmamap,
1479 		    BUS_DMASYNC_POSTWRITE);
1480 		bus_dmamap_unload(sc->sc_tdmatag, txs->txs_dmamap);
1481 		if (txs->txs_mbuf != NULL) {
1482 			m_freem(txs->txs_mbuf);
1483 			txs->txs_mbuf = NULL;
1484 		}
1485 
1486 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
1487 
1488 		if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
1489 		progress = 1;
1490 	}
1491 
1492 #ifdef GEM_DEBUG
1493 	CTR4(KTR_GEM, "%s: GEM_TX_STATE_MACHINE %x GEM_TX_DATA_PTR %llx "
1494 	    "GEM_TX_COMPLETION %x",
1495 	    __func__, GEM_BANK1_READ_4(sc, GEM_TX_STATE_MACHINE),
1496 	    ((long long)GEM_BANK1_READ_4(sc, GEM_TX_DATA_PTR_HI) << 32) |
1497 	    GEM_BANK1_READ_4(sc, GEM_TX_DATA_PTR_LO),
1498 	    GEM_BANK1_READ_4(sc, GEM_TX_COMPLETION));
1499 #endif
1500 
1501 	if (progress) {
1502 		if (sc->sc_txfree == GEM_NTXDESC - 1)
1503 			sc->sc_txwin = 0;
1504 
1505 		/*
1506 		 * We freed some descriptors, so reset IFF_DRV_OACTIVE
1507 		 * and restart.
1508 		 */
1509 		ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
1510 		if (STAILQ_EMPTY(&sc->sc_txdirtyq))
1511 		    sc->sc_wdog_timer = 0;
1512 		gem_start_locked(ifp);
1513 	}
1514 
1515 #ifdef GEM_DEBUG
1516 	CTR3(KTR_GEM, "%s: %s: watchdog %d",
1517 	    device_get_name(sc->sc_dev), __func__, sc->sc_wdog_timer);
1518 #endif
1519 }
1520 
1521 #ifdef GEM_RINT_TIMEOUT
1522 static void
1523 gem_rint_timeout(void *arg)
1524 {
1525 	struct gem_softc *sc = arg;
1526 
1527 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1528 
1529 	gem_rint(sc);
1530 }
1531 #endif
1532 
1533 static void
1534 gem_rint(struct gem_softc *sc)
1535 {
1536 	struct ifnet *ifp = sc->sc_ifp;
1537 	struct mbuf *m;
1538 	uint64_t rxstat;
1539 	uint32_t rxcomp;
1540 
1541 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1542 
1543 #ifdef GEM_RINT_TIMEOUT
1544 	callout_stop(&sc->sc_rx_ch);
1545 #endif
1546 #ifdef GEM_DEBUG
1547 	CTR2(KTR_GEM, "%s: %s", device_get_name(sc->sc_dev), __func__);
1548 #endif
1549 
1550 	/*
1551 	 * Read the completion register once.  This limits
1552 	 * how long the following loop can execute.
1553 	 */
1554 	rxcomp = GEM_BANK1_READ_4(sc, GEM_RX_COMPLETION);
1555 #ifdef GEM_DEBUG
1556 	CTR3(KTR_GEM, "%s: sc->sc_rxptr %d, complete %d",
1557 	    __func__, sc->sc_rxptr, rxcomp);
1558 #endif
1559 	GEM_CDSYNC(sc, BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
1560 	for (; sc->sc_rxptr != rxcomp;) {
1561 		m = sc->sc_rxsoft[sc->sc_rxptr].rxs_mbuf;
1562 		rxstat = GEM_DMA_READ(sc,
1563 		    sc->sc_rxdescs[sc->sc_rxptr].gd_flags);
1564 
1565 		if (rxstat & GEM_RD_OWN) {
1566 #ifdef GEM_RINT_TIMEOUT
1567 			/*
1568 			 * The descriptor is still marked as owned, although
1569 			 * it is supposed to have completed.  This has been
1570 			 * observed on some machines.  Just exiting here
1571 			 * might leave the packet sitting around until another
1572 			 * one arrives to trigger a new interrupt, which is
1573 			 * generally undesirable, so set up a timeout.
1574 			 */
1575 			callout_reset(&sc->sc_rx_ch, GEM_RXOWN_TICKS,
1576 			    gem_rint_timeout, sc);
1577 #endif
1578 			m = NULL;
1579 			goto kickit;
1580 		}
1581 
1582 		if (rxstat & GEM_RD_BAD_CRC) {
1583 			if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
1584 			device_printf(sc->sc_dev, "receive error: CRC error\n");
1585 			GEM_INIT_RXDESC(sc, sc->sc_rxptr);
1586 			m = NULL;
1587 			goto kickit;
1588 		}
1589 
1590 #ifdef GEM_DEBUG
1591 		if ((ifp->if_flags & IFF_DEBUG) != 0) {
1592 			printf("    rxsoft %p descriptor %d: ",
1593 			    &sc->sc_rxsoft[sc->sc_rxptr], sc->sc_rxptr);
1594 			printf("gd_flags: 0x%016llx\t",
1595 			    (long long)GEM_DMA_READ(sc,
1596 			    sc->sc_rxdescs[sc->sc_rxptr].gd_flags));
1597 			printf("gd_addr: 0x%016llx\n",
1598 			    (long long)GEM_DMA_READ(sc,
1599 			    sc->sc_rxdescs[sc->sc_rxptr].gd_addr));
1600 		}
1601 #endif
1602 
1603 		/*
1604 		 * Allocate a new mbuf cluster.  If that fails, we are
1605 		 * out of memory, and must drop the packet and recycle
1606 		 * the buffer that's already attached to this descriptor.
1607 		 */
1608 		if (gem_add_rxbuf(sc, sc->sc_rxptr) != 0) {
1609 			if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1);
1610 			GEM_INIT_RXDESC(sc, sc->sc_rxptr);
1611 			m = NULL;
1612 		}
1613 
1614  kickit:
1615 		/*
1616 		 * Update the RX kick register.  This register has to point
1617 		 * to the descriptor after the last valid one (before the
1618 		 * current batch) and for optimum performance should be
1619 		 * incremented in multiples of 4 (the DMA engine fetches/
1620 		 * updates descriptors in batches of 4).
1621 		 */
1622 		sc->sc_rxptr = GEM_NEXTRX(sc->sc_rxptr);
1623 		if ((sc->sc_rxptr % 4) == 0) {
1624 			GEM_CDSYNC(sc,
1625 			    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1626 			GEM_BANK1_WRITE_4(sc, GEM_RX_KICK,
1627 			    (sc->sc_rxptr + GEM_NRXDESC - 4) &
1628 			    GEM_NRXDESC_MASK);
1629 		}
1630 
1631 		if (m == NULL) {
1632 			if (rxstat & GEM_RD_OWN)
1633 				break;
1634 			continue;
1635 		}
1636 
1637 		if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
1638 		m->m_data += ETHER_ALIGN; /* first byte offset */
1639 		m->m_pkthdr.rcvif = ifp;
1640 		m->m_pkthdr.len = m->m_len = GEM_RD_BUFLEN(rxstat);
1641 
1642 		if ((ifp->if_capenable & IFCAP_RXCSUM) != 0)
1643 			gem_rxcksum(m, rxstat);
1644 
1645 		/* Pass it on. */
1646 		GEM_UNLOCK(sc);
1647 		(*ifp->if_input)(ifp, m);
1648 		GEM_LOCK(sc);
1649 	}
1650 
1651 #ifdef GEM_DEBUG
1652 	CTR3(KTR_GEM, "%s: done sc->sc_rxptr %d, complete %d", __func__,
1653 	    sc->sc_rxptr, GEM_BANK1_READ_4(sc, GEM_RX_COMPLETION));
1654 #endif
1655 }
1656 
1657 static int
1658 gem_add_rxbuf(struct gem_softc *sc, int idx)
1659 {
1660 	struct gem_rxsoft *rxs = &sc->sc_rxsoft[idx];
1661 	struct mbuf *m;
1662 	bus_dma_segment_t segs[1];
1663 	int error, nsegs;
1664 
1665 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1666 
1667 	m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
1668 	if (m == NULL)
1669 		return (ENOBUFS);
1670 	m->m_len = m->m_pkthdr.len = m->m_ext.ext_size;
1671 
1672 #ifdef GEM_DEBUG
1673 	/* Bzero the packet to check DMA. */
1674 	memset(m->m_ext.ext_buf, 0, m->m_ext.ext_size);
1675 #endif
1676 
1677 	if (rxs->rxs_mbuf != NULL) {
1678 		bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
1679 		    BUS_DMASYNC_POSTREAD);
1680 		bus_dmamap_unload(sc->sc_rdmatag, rxs->rxs_dmamap);
1681 	}
1682 
1683 	error = bus_dmamap_load_mbuf_sg(sc->sc_rdmatag, rxs->rxs_dmamap,
1684 	    m, segs, &nsegs, BUS_DMA_NOWAIT);
1685 	if (error != 0) {
1686 		device_printf(sc->sc_dev,
1687 		    "cannot load RS DMA map %d, error = %d\n", idx, error);
1688 		m_freem(m);
1689 		return (error);
1690 	}
1691 	/* If nsegs is wrong then the stack is corrupt. */
1692 	KASSERT(nsegs == 1,
1693 	    ("%s: too many DMA segments (%d)", __func__, nsegs));
1694 	rxs->rxs_mbuf = m;
1695 	rxs->rxs_paddr = segs[0].ds_addr;
1696 
1697 	bus_dmamap_sync(sc->sc_rdmatag, rxs->rxs_dmamap,
1698 	    BUS_DMASYNC_PREREAD);
1699 
1700 	GEM_INIT_RXDESC(sc, idx);
1701 
1702 	return (0);
1703 }
1704 
1705 static void
1706 gem_eint(struct gem_softc *sc, u_int status)
1707 {
1708 
1709 	if_inc_counter(sc->sc_ifp, IFCOUNTER_IERRORS, 1);
1710 	if ((status & GEM_INTR_RX_TAG_ERR) != 0) {
1711 		gem_reset_rxdma(sc);
1712 		return;
1713 	}
1714 
1715 	device_printf(sc->sc_dev, "%s: status 0x%x", __func__, status);
1716 	if ((status & GEM_INTR_BERR) != 0) {
1717 		if ((sc->sc_flags & GEM_PCI) != 0)
1718 			printf(", PCI bus error 0x%x\n",
1719 			    GEM_BANK1_READ_4(sc, GEM_PCI_ERROR_STATUS));
1720 		else
1721 			printf(", SBus error 0x%x\n",
1722 			    GEM_BANK1_READ_4(sc, GEM_SBUS_STATUS));
1723 	}
1724 }
1725 
1726 void
1727 gem_intr(void *v)
1728 {
1729 	struct gem_softc *sc = v;
1730 	uint32_t status, status2;
1731 
1732 	GEM_LOCK(sc);
1733 	status = GEM_BANK1_READ_4(sc, GEM_STATUS);
1734 
1735 #ifdef GEM_DEBUG
1736 	CTR4(KTR_GEM, "%s: %s: cplt %x, status %x",
1737 	    device_get_name(sc->sc_dev), __func__,
1738 	    (status >> GEM_STATUS_TX_COMPLETION_SHFT), (u_int)status);
1739 
1740 	/*
1741 	 * PCS interrupts must be cleared, otherwise no traffic is passed!
1742 	 */
1743 	if ((status & GEM_INTR_PCS) != 0) {
1744 		status2 =
1745 		    GEM_BANK1_READ_4(sc, GEM_MII_INTERRUP_STATUS) |
1746 		    GEM_BANK1_READ_4(sc, GEM_MII_INTERRUP_STATUS);
1747 		if ((status2 & GEM_MII_INTERRUP_LINK) != 0)
1748 			device_printf(sc->sc_dev,
1749 			    "%s: PCS link status changed\n", __func__);
1750 	}
1751 	if ((status & GEM_MAC_CONTROL_STATUS) != 0) {
1752 		status2 = GEM_BANK1_READ_4(sc, GEM_MAC_CONTROL_STATUS);
1753 		if ((status2 & GEM_MAC_PAUSED) != 0)
1754 			device_printf(sc->sc_dev,
1755 			    "%s: PAUSE received (PAUSE time %d slots)\n",
1756 			    __func__, GEM_MAC_PAUSE_TIME(status2));
1757 		if ((status2 & GEM_MAC_PAUSE) != 0)
1758 			device_printf(sc->sc_dev,
1759 			    "%s: transited to PAUSE state\n", __func__);
1760 		if ((status2 & GEM_MAC_RESUME) != 0)
1761 			device_printf(sc->sc_dev,
1762 			    "%s: transited to non-PAUSE state\n", __func__);
1763 	}
1764 	if ((status & GEM_INTR_MIF) != 0)
1765 		device_printf(sc->sc_dev, "%s: MIF interrupt\n", __func__);
1766 #endif
1767 
1768 	if (__predict_false(status &
1769 	    (GEM_INTR_RX_TAG_ERR | GEM_INTR_PERR | GEM_INTR_BERR)) != 0)
1770 		gem_eint(sc, status);
1771 
1772 	if ((status & (GEM_INTR_RX_DONE | GEM_INTR_RX_NOBUF)) != 0)
1773 		gem_rint(sc);
1774 
1775 	if ((status & (GEM_INTR_TX_EMPTY | GEM_INTR_TX_INTME)) != 0)
1776 		gem_tint(sc);
1777 
1778 	if (__predict_false((status & GEM_INTR_TX_MAC) != 0)) {
1779 		status2 = GEM_BANK1_READ_4(sc, GEM_MAC_TX_STATUS);
1780 		if ((status2 &
1781 		    ~(GEM_MAC_TX_XMIT_DONE | GEM_MAC_TX_DEFER_EXP |
1782 		    GEM_MAC_TX_PEAK_EXP)) != 0)
1783 			device_printf(sc->sc_dev,
1784 			    "MAC TX fault, status %x\n", status2);
1785 		if ((status2 &
1786 		    (GEM_MAC_TX_UNDERRUN | GEM_MAC_TX_PKT_TOO_LONG)) != 0) {
1787 			if_inc_counter(sc->sc_ifp, IFCOUNTER_OERRORS, 1);
1788 			sc->sc_ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
1789 			gem_init_locked(sc);
1790 		}
1791 	}
1792 	if (__predict_false((status & GEM_INTR_RX_MAC) != 0)) {
1793 		status2 = GEM_BANK1_READ_4(sc, GEM_MAC_RX_STATUS);
1794 		/*
1795 		 * At least with GEM_SUN_GEM and some GEM_SUN_ERI
1796 		 * revisions GEM_MAC_RX_OVERFLOW happen often due to a
1797 		 * silicon bug so handle them silently.  Moreover, it's
1798 		 * likely that the receiver has hung so we reset it.
1799 		 */
1800 		if ((status2 & GEM_MAC_RX_OVERFLOW) != 0) {
1801 			if_inc_counter(sc->sc_ifp, IFCOUNTER_IERRORS, 1);
1802 			gem_reset_rxdma(sc);
1803 		} else if ((status2 &
1804 		    ~(GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT)) != 0)
1805 			device_printf(sc->sc_dev,
1806 			    "MAC RX fault, status %x\n", status2);
1807 	}
1808 	GEM_UNLOCK(sc);
1809 }
1810 
1811 static int
1812 gem_watchdog(struct gem_softc *sc)
1813 {
1814 	struct ifnet *ifp = sc->sc_ifp;
1815 
1816 	GEM_LOCK_ASSERT(sc, MA_OWNED);
1817 
1818 #ifdef GEM_DEBUG
1819 	CTR4(KTR_GEM,
1820 	    "%s: GEM_RX_CONFIG %x GEM_MAC_RX_STATUS %x GEM_MAC_RX_CONFIG %x",
1821 	    __func__, GEM_BANK1_READ_4(sc, GEM_RX_CONFIG),
1822 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_STATUS),
1823 	    GEM_BANK1_READ_4(sc, GEM_MAC_RX_CONFIG));
1824 	CTR4(KTR_GEM,
1825 	    "%s: GEM_TX_CONFIG %x GEM_MAC_TX_STATUS %x GEM_MAC_TX_CONFIG %x",
1826 	    __func__, GEM_BANK1_READ_4(sc, GEM_TX_CONFIG),
1827 	    GEM_BANK1_READ_4(sc, GEM_MAC_TX_STATUS),
1828 	    GEM_BANK1_READ_4(sc, GEM_MAC_TX_CONFIG));
1829 #endif
1830 
1831 	if (sc->sc_wdog_timer == 0 || --sc->sc_wdog_timer != 0)
1832 		return (0);
1833 
1834 	if ((sc->sc_flags & GEM_LINK) != 0)
1835 		device_printf(sc->sc_dev, "device timeout\n");
1836 	else if (bootverbose)
1837 		device_printf(sc->sc_dev, "device timeout (no link)\n");
1838 	if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
1839 
1840 	/* Try to get more packets going. */
1841 	ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
1842 	gem_init_locked(sc);
1843 	gem_start_locked(ifp);
1844 	return (EJUSTRETURN);
1845 }
1846 
1847 static void
1848 gem_mifinit(struct gem_softc *sc)
1849 {
1850 
1851 	/* Configure the MIF in frame mode. */
1852 	GEM_BANK1_WRITE_4(sc, GEM_MIF_CONFIG,
1853 	    GEM_BANK1_READ_4(sc, GEM_MIF_CONFIG) & ~GEM_MIF_CONFIG_BB_ENA);
1854 	GEM_BANK1_BARRIER(sc, GEM_MIF_CONFIG, 4,
1855 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1856 }
1857 
1858 /*
1859  * MII interface
1860  *
1861  * The MII interface supports at least three different operating modes:
1862  *
1863  * Bitbang mode is implemented using data, clock and output enable registers.
1864  *
1865  * Frame mode is implemented by loading a complete frame into the frame
1866  * register and polling the valid bit for completion.
1867  *
1868  * Polling mode uses the frame register but completion is indicated by
1869  * an interrupt.
1870  *
1871  */
1872 int
1873 gem_mii_readreg(device_t dev, int phy, int reg)
1874 {
1875 	struct gem_softc *sc;
1876 	int n;
1877 	uint32_t v;
1878 
1879 #ifdef GEM_DEBUG_PHY
1880 	printf("%s: phy %d reg %d\n", __func__, phy, reg);
1881 #endif
1882 
1883 	sc = device_get_softc(dev);
1884 	if ((sc->sc_flags & GEM_SERDES) != 0) {
1885 		switch (reg) {
1886 		case MII_BMCR:
1887 			reg = GEM_MII_CONTROL;
1888 			break;
1889 		case MII_BMSR:
1890 			reg = GEM_MII_STATUS;
1891 			break;
1892 		case MII_PHYIDR1:
1893 		case MII_PHYIDR2:
1894 			return (0);
1895 		case MII_ANAR:
1896 			reg = GEM_MII_ANAR;
1897 			break;
1898 		case MII_ANLPAR:
1899 			reg = GEM_MII_ANLPAR;
1900 			break;
1901 		case MII_EXTSR:
1902 			return (EXTSR_1000XFDX | EXTSR_1000XHDX);
1903 		default:
1904 			device_printf(sc->sc_dev,
1905 			    "%s: unhandled register %d\n", __func__, reg);
1906 			return (0);
1907 		}
1908 		return (GEM_BANK1_READ_4(sc, reg));
1909 	}
1910 
1911 	/* Construct the frame command. */
1912 	v = GEM_MIF_FRAME_READ |
1913 	    (phy << GEM_MIF_PHY_SHIFT) |
1914 	    (reg << GEM_MIF_REG_SHIFT);
1915 
1916 	GEM_BANK1_WRITE_4(sc, GEM_MIF_FRAME, v);
1917 	GEM_BANK1_BARRIER(sc, GEM_MIF_FRAME, 4,
1918 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1919 	for (n = 0; n < 100; n++) {
1920 		DELAY(1);
1921 		v = GEM_BANK1_READ_4(sc, GEM_MIF_FRAME);
1922 		if (v & GEM_MIF_FRAME_TA0)
1923 			return (v & GEM_MIF_FRAME_DATA);
1924 	}
1925 
1926 	device_printf(sc->sc_dev, "%s: timed out\n", __func__);
1927 	return (0);
1928 }
1929 
1930 int
1931 gem_mii_writereg(device_t dev, int phy, int reg, int val)
1932 {
1933 	struct gem_softc *sc;
1934 	int n;
1935 	uint32_t v;
1936 
1937 #ifdef GEM_DEBUG_PHY
1938 	printf("%s: phy %d reg %d val %x\n", phy, reg, val, __func__);
1939 #endif
1940 
1941 	sc = device_get_softc(dev);
1942 	if ((sc->sc_flags & GEM_SERDES) != 0) {
1943 		switch (reg) {
1944 		case MII_BMSR:
1945 			reg = GEM_MII_STATUS;
1946 			break;
1947 		case MII_BMCR:
1948 			reg = GEM_MII_CONTROL;
1949 			if ((val & GEM_MII_CONTROL_RESET) == 0)
1950 				break;
1951 			GEM_BANK1_WRITE_4(sc, GEM_MII_CONTROL, val);
1952 			GEM_BANK1_BARRIER(sc, GEM_MII_CONTROL, 4,
1953 			    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1954 			if (!GEM_BANK1_BITWAIT(sc, GEM_MII_CONTROL,
1955 			    GEM_MII_CONTROL_RESET, 0))
1956 				device_printf(sc->sc_dev,
1957 				    "cannot reset PCS\n");
1958 			/* FALLTHROUGH */
1959 		case MII_ANAR:
1960 			GEM_BANK1_WRITE_4(sc, GEM_MII_CONFIG, 0);
1961 			GEM_BANK1_BARRIER(sc, GEM_MII_CONFIG, 4,
1962 			    BUS_SPACE_BARRIER_WRITE);
1963 			GEM_BANK1_WRITE_4(sc, GEM_MII_ANAR, val);
1964 			GEM_BANK1_BARRIER(sc, GEM_MII_ANAR, 4,
1965 			    BUS_SPACE_BARRIER_WRITE);
1966 			GEM_BANK1_WRITE_4(sc, GEM_MII_SLINK_CONTROL,
1967 			    GEM_MII_SLINK_LOOPBACK | GEM_MII_SLINK_EN_SYNC_D);
1968 			GEM_BANK1_BARRIER(sc, GEM_MII_SLINK_CONTROL, 4,
1969 			    BUS_SPACE_BARRIER_WRITE);
1970 			GEM_BANK1_WRITE_4(sc, GEM_MII_CONFIG,
1971 			    GEM_MII_CONFIG_ENABLE);
1972 			GEM_BANK1_BARRIER(sc, GEM_MII_CONFIG, 4,
1973 			    BUS_SPACE_BARRIER_WRITE);
1974 			return (0);
1975 		case MII_ANLPAR:
1976 			reg = GEM_MII_ANLPAR;
1977 			break;
1978 		default:
1979 			device_printf(sc->sc_dev,
1980 			    "%s: unhandled register %d\n", __func__, reg);
1981 			return (0);
1982 		}
1983 		GEM_BANK1_WRITE_4(sc, reg, val);
1984 		GEM_BANK1_BARRIER(sc, reg, 4,
1985 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1986 		return (0);
1987 	}
1988 
1989 	/* Construct the frame command. */
1990 	v = GEM_MIF_FRAME_WRITE |
1991 	    (phy << GEM_MIF_PHY_SHIFT) |
1992 	    (reg << GEM_MIF_REG_SHIFT) |
1993 	    (val & GEM_MIF_FRAME_DATA);
1994 
1995 	GEM_BANK1_WRITE_4(sc, GEM_MIF_FRAME, v);
1996 	GEM_BANK1_BARRIER(sc, GEM_MIF_FRAME, 4,
1997 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
1998 	for (n = 0; n < 100; n++) {
1999 		DELAY(1);
2000 		v = GEM_BANK1_READ_4(sc, GEM_MIF_FRAME);
2001 		if (v & GEM_MIF_FRAME_TA0)
2002 			return (1);
2003 	}
2004 
2005 	device_printf(sc->sc_dev, "%s: timed out\n", __func__);
2006 	return (0);
2007 }
2008 
2009 void
2010 gem_mii_statchg(device_t dev)
2011 {
2012 	struct gem_softc *sc;
2013 	int gigabit;
2014 	uint32_t rxcfg, txcfg, v;
2015 
2016 	sc = device_get_softc(dev);
2017 
2018 	GEM_LOCK_ASSERT(sc, MA_OWNED);
2019 
2020 #ifdef GEM_DEBUG
2021 	if ((sc->sc_ifp->if_flags & IFF_DEBUG) != 0)
2022 		device_printf(sc->sc_dev, "%s: status change\n", __func__);
2023 #endif
2024 
2025 	if ((sc->sc_mii->mii_media_status & IFM_ACTIVE) != 0 &&
2026 	    IFM_SUBTYPE(sc->sc_mii->mii_media_active) != IFM_NONE)
2027 		sc->sc_flags |= GEM_LINK;
2028 	else
2029 		sc->sc_flags &= ~GEM_LINK;
2030 
2031 	switch (IFM_SUBTYPE(sc->sc_mii->mii_media_active)) {
2032 	case IFM_1000_SX:
2033 	case IFM_1000_LX:
2034 	case IFM_1000_CX:
2035 	case IFM_1000_T:
2036 		gigabit = 1;
2037 		break;
2038 	default:
2039 		gigabit = 0;
2040 	}
2041 
2042 	/*
2043 	 * The configuration done here corresponds to the steps F) and
2044 	 * G) and as far as enabling of RX and TX MAC goes also step H)
2045 	 * of the initialization sequence outlined in section 3.2.1 of
2046 	 * the GEM Gigabit Ethernet ASIC Specification.
2047 	 */
2048 
2049 	rxcfg = sc->sc_mac_rxcfg;
2050 	rxcfg &= ~GEM_MAC_RX_CARR_EXTEND;
2051 	txcfg = GEM_MAC_TX_ENA_IPG0 | GEM_MAC_TX_NGU | GEM_MAC_TX_NGU_LIMIT;
2052 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) != 0)
2053 		txcfg |= GEM_MAC_TX_IGN_CARRIER | GEM_MAC_TX_IGN_COLLIS;
2054 	else if (gigabit != 0) {
2055 		rxcfg |= GEM_MAC_RX_CARR_EXTEND;
2056 		txcfg |= GEM_MAC_TX_CARR_EXTEND;
2057 	}
2058 	(void)gem_disable_tx(sc);
2059 	GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG, txcfg);
2060 	(void)gem_disable_rx(sc);
2061 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, rxcfg);
2062 
2063 	v = GEM_BANK1_READ_4(sc, GEM_MAC_CONTROL_CONFIG) &
2064 	    ~(GEM_MAC_CC_RX_PAUSE | GEM_MAC_CC_TX_PAUSE);
2065 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
2066 	    IFM_ETH_RXPAUSE) != 0)
2067 		v |= GEM_MAC_CC_RX_PAUSE;
2068 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
2069 	    IFM_ETH_TXPAUSE) != 0)
2070 		v |= GEM_MAC_CC_TX_PAUSE;
2071 	GEM_BANK1_WRITE_4(sc, GEM_MAC_CONTROL_CONFIG, v);
2072 
2073 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) == 0 &&
2074 	    gigabit != 0)
2075 		GEM_BANK1_WRITE_4(sc, GEM_MAC_SLOT_TIME,
2076 		    GEM_MAC_SLOT_TIME_CARR_EXTEND);
2077 	else
2078 		GEM_BANK1_WRITE_4(sc, GEM_MAC_SLOT_TIME,
2079 		    GEM_MAC_SLOT_TIME_NORMAL);
2080 
2081 	/* XIF Configuration */
2082 	v = GEM_MAC_XIF_LINK_LED;
2083 	v |= GEM_MAC_XIF_TX_MII_ENA;
2084 	if ((sc->sc_flags & GEM_SERDES) == 0) {
2085 		if ((GEM_BANK1_READ_4(sc, GEM_MIF_CONFIG) &
2086 		    GEM_MIF_CONFIG_PHY_SEL) != 0) {
2087 			/* External MII needs echo disable if half duplex. */
2088 			if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) &
2089 			    IFM_FDX) == 0)
2090 				v |= GEM_MAC_XIF_ECHO_DISABL;
2091 		} else
2092 			/*
2093 			 * Internal MII needs buffer enable.
2094 			 * XXX buffer enable makes only sense for an
2095 			 * external PHY.
2096 			 */
2097 			v |= GEM_MAC_XIF_MII_BUF_ENA;
2098 	}
2099 	if (gigabit != 0)
2100 		v |= GEM_MAC_XIF_GMII_MODE;
2101 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) != 0)
2102 		v |= GEM_MAC_XIF_FDPLX_LED;
2103 	GEM_BANK1_WRITE_4(sc, GEM_MAC_XIF_CONFIG, v);
2104 
2105 	sc->sc_mac_rxcfg = rxcfg;
2106 	if ((sc->sc_ifp->if_drv_flags & IFF_DRV_RUNNING) != 0 &&
2107 	    (sc->sc_flags & GEM_LINK) != 0) {
2108 		GEM_BANK1_WRITE_4(sc, GEM_MAC_TX_CONFIG,
2109 		    txcfg | GEM_MAC_TX_ENABLE);
2110 		GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG,
2111 		    rxcfg | GEM_MAC_RX_ENABLE);
2112 	}
2113 }
2114 
2115 int
2116 gem_mediachange(struct ifnet *ifp)
2117 {
2118 	struct gem_softc *sc = ifp->if_softc;
2119 	int error;
2120 
2121 	/* XXX add support for serial media. */
2122 
2123 	GEM_LOCK(sc);
2124 	error = mii_mediachg(sc->sc_mii);
2125 	GEM_UNLOCK(sc);
2126 	return (error);
2127 }
2128 
2129 void
2130 gem_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
2131 {
2132 	struct gem_softc *sc = ifp->if_softc;
2133 
2134 	GEM_LOCK(sc);
2135 	if ((ifp->if_flags & IFF_UP) == 0) {
2136 		GEM_UNLOCK(sc);
2137 		return;
2138 	}
2139 
2140 	mii_pollstat(sc->sc_mii);
2141 	ifmr->ifm_active = sc->sc_mii->mii_media_active;
2142 	ifmr->ifm_status = sc->sc_mii->mii_media_status;
2143 	GEM_UNLOCK(sc);
2144 }
2145 
2146 static int
2147 gem_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
2148 {
2149 	struct gem_softc *sc = ifp->if_softc;
2150 	struct ifreq *ifr = (struct ifreq *)data;
2151 	int error;
2152 
2153 	error = 0;
2154 	switch (cmd) {
2155 	case SIOCSIFFLAGS:
2156 		GEM_LOCK(sc);
2157 		if ((ifp->if_flags & IFF_UP) != 0) {
2158 			if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0 &&
2159 			    ((ifp->if_flags ^ sc->sc_ifflags) &
2160 			    (IFF_ALLMULTI | IFF_PROMISC)) != 0)
2161 				gem_setladrf(sc);
2162 			else
2163 				gem_init_locked(sc);
2164 		} else if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
2165 			gem_stop(ifp, 0);
2166 		if ((ifp->if_flags & IFF_LINK0) != 0)
2167 			sc->sc_csum_features |= CSUM_UDP;
2168 		else
2169 			sc->sc_csum_features &= ~CSUM_UDP;
2170 		if ((ifp->if_capenable & IFCAP_TXCSUM) != 0)
2171 			ifp->if_hwassist = sc->sc_csum_features;
2172 		sc->sc_ifflags = ifp->if_flags;
2173 		GEM_UNLOCK(sc);
2174 		break;
2175 	case SIOCADDMULTI:
2176 	case SIOCDELMULTI:
2177 		GEM_LOCK(sc);
2178 		if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
2179 			gem_setladrf(sc);
2180 		GEM_UNLOCK(sc);
2181 		break;
2182 	case SIOCGIFMEDIA:
2183 	case SIOCSIFMEDIA:
2184 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii->mii_media, cmd);
2185 		break;
2186 	case SIOCSIFCAP:
2187 		GEM_LOCK(sc);
2188 		ifp->if_capenable = ifr->ifr_reqcap;
2189 		if ((ifp->if_capenable & IFCAP_TXCSUM) != 0)
2190 			ifp->if_hwassist = sc->sc_csum_features;
2191 		else
2192 			ifp->if_hwassist = 0;
2193 		GEM_UNLOCK(sc);
2194 		break;
2195 	default:
2196 		error = ether_ioctl(ifp, cmd, data);
2197 		break;
2198 	}
2199 
2200 	return (error);
2201 }
2202 
2203 static void
2204 gem_setladrf(struct gem_softc *sc)
2205 {
2206 	struct ifnet *ifp = sc->sc_ifp;
2207 	struct ifmultiaddr *inm;
2208 	int i;
2209 	uint32_t hash[16];
2210 	uint32_t crc, v;
2211 
2212 	GEM_LOCK_ASSERT(sc, MA_OWNED);
2213 
2214 	/*
2215 	 * Turn off the RX MAC and the hash filter as required by the Sun GEM
2216 	 * programming restrictions.
2217 	 */
2218 	v = sc->sc_mac_rxcfg & ~GEM_MAC_RX_HASH_FILTER;
2219 	GEM_BANK1_WRITE_4(sc, GEM_MAC_RX_CONFIG, v);
2220 	GEM_BANK1_BARRIER(sc, GEM_MAC_RX_CONFIG, 4,
2221 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
2222 	if (!GEM_BANK1_BITWAIT(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_HASH_FILTER |
2223 	    GEM_MAC_RX_ENABLE, 0))
2224 		device_printf(sc->sc_dev,
2225 		    "cannot disable RX MAC or hash filter\n");
2226 
2227 	v &= ~(GEM_MAC_RX_PROMISCUOUS | GEM_MAC_RX_PROMISC_GRP);
2228 	if ((ifp->if_flags & IFF_PROMISC) != 0) {
2229 		v |= GEM_MAC_RX_PROMISCUOUS;
2230 		goto chipit;
2231 	}
2232 	if ((ifp->if_flags & IFF_ALLMULTI) != 0) {
2233 		v |= GEM_MAC_RX_PROMISC_GRP;
2234 		goto chipit;
2235 	}
2236 
2237 	/*
2238 	 * Set up multicast address filter by passing all multicast
2239 	 * addresses through a crc generator, and then using the high
2240 	 * order 8 bits as an index into the 256 bit logical address
2241 	 * filter.  The high order 4 bits selects the word, while the
2242 	 * other 4 bits select the bit within the word (where bit 0
2243 	 * is the MSB).
2244 	 */
2245 
2246 	/* Clear the hash table. */
2247 	memset(hash, 0, sizeof(hash));
2248 
2249 	if_maddr_rlock(ifp);
2250 	TAILQ_FOREACH(inm, &ifp->if_multiaddrs, ifma_link) {
2251 		if (inm->ifma_addr->sa_family != AF_LINK)
2252 			continue;
2253 		crc = ether_crc32_le(LLADDR((struct sockaddr_dl *)
2254 		    inm->ifma_addr), ETHER_ADDR_LEN);
2255 
2256 		/* We just want the 8 most significant bits. */
2257 		crc >>= 24;
2258 
2259 		/* Set the corresponding bit in the filter. */
2260 		hash[crc >> 4] |= 1 << (15 - (crc & 15));
2261 	}
2262 	if_maddr_runlock(ifp);
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