xref: /freebsd/sys/dev/gem/if_gem.c (revision 42c159fe388a3765f69860c84183700af37aca8a)
1 /*
2  * Copyright (C) 2001 Eduardo Horvath.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR  ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR  BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  *	from: NetBSD: gem.c,v 1.9 2001/10/21 20:45:15 thorpej Exp
27  *
28  * $FreeBSD$
29  */
30 
31 /*
32  * Driver for Sun GEM ethernet controllers.
33  */
34 
35 #define	GEM_DEBUG
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/bus.h>
40 #include <sys/callout.h>
41 #include <sys/mbuf.h>
42 #include <sys/malloc.h>
43 #include <sys/kernel.h>
44 #include <sys/socket.h>
45 #include <sys/sockio.h>
46 
47 #include <net/ethernet.h>
48 #include <net/if.h>
49 #include <net/if_arp.h>
50 #include <net/if_dl.h>
51 #include <net/if_media.h>
52 
53 #include <machine/bus.h>
54 
55 #include <dev/mii/mii.h>
56 #include <dev/mii/miivar.h>
57 
58 #include <gem/if_gemreg.h>
59 #include <gem/if_gemvar.h>
60 
61 #define TRIES	10000
62 
63 static void	gem_start(struct ifnet *);
64 static void	gem_stop(struct ifnet *, int);
65 static int	gem_ioctl(struct ifnet *, u_long, caddr_t);
66 static void	gem_cddma_callback(void *, bus_dma_segment_t *, int, int);
67 static void	gem_rxdma_callback(void *, bus_dma_segment_t *, int, int);
68 static void	gem_txdma_callback(void *, bus_dma_segment_t *, int, int);
69 static void	gem_tick(void *);
70 static void	gem_watchdog(struct ifnet *);
71 static void	gem_init(void *);
72 static void	gem_init_regs(struct gem_softc *sc);
73 static int	gem_ringsize(int sz);
74 static int	gem_meminit(struct gem_softc *);
75 static int	gem_dmamap_load_mbuf(struct gem_softc *, struct mbuf *,
76     bus_dmamap_callback_t *,  struct gem_txjob *, int);
77 static void	gem_dmamap_unload_mbuf(struct gem_softc *, struct gem_txjob *);
78 static void	gem_dmamap_commit_mbuf(struct gem_softc *, struct gem_txjob *);
79 static void	gem_mifinit(struct gem_softc *);
80 static int	gem_bitwait(struct gem_softc *sc, bus_addr_t r,
81     u_int32_t clr, u_int32_t set);
82 static int	gem_reset_rx(struct gem_softc *);
83 static int	gem_reset_tx(struct gem_softc *);
84 static int	gem_disable_rx(struct gem_softc *);
85 static int	gem_disable_tx(struct gem_softc *);
86 static void	gem_rxdrain(struct gem_softc *);
87 static int	gem_add_rxbuf(struct gem_softc *, int);
88 static void	gem_setladrf(struct gem_softc *);
89 
90 struct mbuf	*gem_get(struct gem_softc *, int, int);
91 static void	gem_eint(struct gem_softc *, u_int);
92 static void	gem_rint(struct gem_softc *);
93 static void	gem_rint_timeout(void *);
94 static void	gem_tint(struct gem_softc *);
95 #ifdef notyet
96 static void	gem_power(int, void *);
97 #endif
98 
99 devclass_t gem_devclass;
100 DRIVER_MODULE(miibus, gem, miibus_driver, miibus_devclass, 0, 0);
101 MODULE_DEPEND(gem, miibus, 1, 1, 1);
102 
103 #ifdef GEM_DEBUG
104 #define	DPRINTF(sc, x)	if ((sc)->sc_arpcom.ac_if.if_flags & IFF_DEBUG) \
105 				printf x
106 #include <sys/ktr.h>
107 #define	KTR_GEM		KTR_CT2
108 #else
109 #define	DPRINTF(sc, x)	/* nothing */
110 #endif
111 
112 #define	GEM_NSEGS GEM_NTXSEGS
113 
114 /*
115  * gem_attach:
116  *
117  *	Attach a Gem interface to the system.
118  */
119 int
120 gem_attach(sc)
121 	struct gem_softc *sc;
122 {
123 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
124 	struct mii_softc *child;
125 	int i, error;
126 
127 	/* Make sure the chip is stopped. */
128 	ifp->if_softc = sc;
129 	gem_reset(sc);
130 
131 	error = bus_dma_tag_create(NULL, 1, 0, BUS_SPACE_MAXADDR_32BIT,
132 	    BUS_SPACE_MAXADDR, NULL, NULL, MCLBYTES, GEM_NSEGS,
133 	    BUS_SPACE_MAXSIZE_32BIT, 0, &sc->sc_pdmatag);
134 	if (error)
135 		return (error);
136 
137 	error = bus_dma_tag_create(sc->sc_pdmatag, 1, 0,
138 	    BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL, MAXBSIZE,
139 	    GEM_NSEGS, BUS_SPACE_MAXSIZE_32BIT, BUS_DMA_ALLOCNOW,
140 	    &sc->sc_dmatag);
141 	if (error)
142 		goto fail_0;
143 
144 	error = bus_dma_tag_create(sc->sc_pdmatag, PAGE_SIZE, 0,
145 	    BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL,
146 	    sizeof(struct gem_control_data), 1,
147 	    sizeof(struct gem_control_data), BUS_DMA_ALLOCNOW,
148 	    &sc->sc_cdmatag);
149 	if (error)
150 		goto fail_1;
151 
152 	/*
153 	 * Allocate the control data structures, and create and load the
154 	 * DMA map for it.
155 	 */
156 	if ((error = bus_dmamem_alloc(sc->sc_cdmatag,
157 	    (void **)&sc->sc_control_data, 0, &sc->sc_cddmamap))) {
158 		device_printf(sc->sc_dev, "unable to allocate control data,"
159 		    " error = %d\n", error);
160 		goto fail_2;
161 	}
162 
163 	sc->sc_cddma = 0;
164 	if ((error = bus_dmamap_load(sc->sc_cdmatag, sc->sc_cddmamap,
165 	    sc->sc_control_data, sizeof(struct gem_control_data),
166 	    gem_cddma_callback, sc, 0)) != 0 || sc->sc_cddma == 0) {
167 		device_printf(sc->sc_dev, "unable to load control data DMA "
168 		    "map, error = %d\n", error);
169 		goto fail_3;
170 	}
171 
172 	/*
173 	 * Initialize the transmit job descriptors.
174 	 */
175 	STAILQ_INIT(&sc->sc_txfreeq);
176 	STAILQ_INIT(&sc->sc_txdirtyq);
177 
178 	/*
179 	 * Create the transmit buffer DMA maps.
180 	 */
181 	error = ENOMEM;
182 	for (i = 0; i < GEM_TXQUEUELEN; i++) {
183 		struct gem_txsoft *txs;
184 
185 		txs = &sc->sc_txsoft[i];
186 		txs->txs_mbuf = NULL;
187 		txs->txs_ndescs = 0;
188 		if ((error = bus_dmamap_create(sc->sc_dmatag, 0,
189 		    &txs->txs_dmamap)) != 0) {
190 			device_printf(sc->sc_dev, "unable to create tx DMA map "
191 			    "%d, error = %d\n", i, error);
192 			goto fail_4;
193 		}
194 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
195 	}
196 
197 	/*
198 	 * Create the receive buffer DMA maps.
199 	 */
200 	for (i = 0; i < GEM_NRXDESC; i++) {
201 		if ((error = bus_dmamap_create(sc->sc_dmatag, 0,
202 		    &sc->sc_rxsoft[i].rxs_dmamap)) != 0) {
203 			device_printf(sc->sc_dev, "unable to create rx DMA map "
204 			    "%d, error = %d\n", i, error);
205 			goto fail_5;
206 		}
207 		sc->sc_rxsoft[i].rxs_mbuf = NULL;
208 	}
209 
210 
211 	gem_mifinit(sc);
212 
213 	if ((error = mii_phy_probe(sc->sc_dev, &sc->sc_miibus, gem_mediachange,
214 	    gem_mediastatus)) != 0) {
215 		device_printf(sc->sc_dev, "phy probe failed: %d\n", error);
216 		goto fail_5;
217 	}
218 	sc->sc_mii = device_get_softc(sc->sc_miibus);
219 
220 	/*
221 	 * From this point forward, the attachment cannot fail.  A failure
222 	 * before this point releases all resources that may have been
223 	 * allocated.
224 	 */
225 
226 	/* Announce ourselves. */
227 	device_printf(sc->sc_dev, "Ethernet address:");
228 	for (i = 0; i < 6; i++)
229 		printf("%c%02x", i > 0 ? ':' : ' ', sc->sc_arpcom.ac_enaddr[i]);
230 	printf("\n");
231 
232 	/* Initialize ifnet structure. */
233 	ifp->if_softc = sc;
234 	ifp->if_unit = device_get_unit(sc->sc_dev);
235 	ifp->if_name = "gem";
236 	ifp->if_mtu = ETHERMTU;
237 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
238 	ifp->if_start = gem_start;
239 	ifp->if_ioctl = gem_ioctl;
240 	ifp->if_watchdog = gem_watchdog;
241 	ifp->if_init = gem_init;
242 	ifp->if_output = ether_output;
243 	ifp->if_snd.ifq_maxlen = GEM_TXQUEUELEN;
244 	/*
245 	 * Walk along the list of attached MII devices and
246 	 * establish an `MII instance' to `phy number'
247 	 * mapping. We'll use this mapping in media change
248 	 * requests to determine which phy to use to program
249 	 * the MIF configuration register.
250 	 */
251 	for (child = LIST_FIRST(&sc->sc_mii->mii_phys); child != NULL;
252 	     child = LIST_NEXT(child, mii_list)) {
253 		/*
254 		 * Note: we support just two PHYs: the built-in
255 		 * internal device and an external on the MII
256 		 * connector.
257 		 */
258 		if (child->mii_phy > 1 || child->mii_inst > 1) {
259 			device_printf(sc->sc_dev, "cannot accomodate "
260 			    "MII device %s at phy %d, instance %d\n",
261 			    device_get_name(child->mii_dev),
262 			    child->mii_phy, child->mii_inst);
263 			continue;
264 		}
265 
266 		sc->sc_phys[child->mii_inst] = child->mii_phy;
267 	}
268 
269 	/*
270 	 * Now select and activate the PHY we will use.
271 	 *
272 	 * The order of preference is External (MDI1),
273 	 * Internal (MDI0), Serial Link (no MII).
274 	 */
275 	if (sc->sc_phys[1]) {
276 #ifdef GEM_DEBUG
277 		printf("using external phy\n");
278 #endif
279 		sc->sc_mif_config |= GEM_MIF_CONFIG_PHY_SEL;
280 	} else {
281 #ifdef GEM_DEBUG
282 		printf("using internal phy\n");
283 #endif
284 		sc->sc_mif_config &= ~GEM_MIF_CONFIG_PHY_SEL;
285 	}
286 	bus_space_write_4(sc->sc_bustag, sc->sc_h, GEM_MIF_CONFIG,
287 	    sc->sc_mif_config);
288 	/* Attach the interface. */
289 	ether_ifattach(ifp, ETHER_BPF_SUPPORTED);
290 
291 #if notyet
292 	/*
293 	 * Add a suspend hook to make sure we come back up after a
294 	 * resume.
295 	 */
296 	sc->sc_powerhook = powerhook_establish(gem_power, sc);
297 	if (sc->sc_powerhook == NULL)
298 		device_printf(sc->sc_dev, "WARNING: unable to establish power "
299 		    "hook\n");
300 #endif
301 
302 	callout_init(&sc->sc_tick_ch, 0);
303 	callout_init(&sc->sc_rx_ch, 0);
304 	return (0);
305 
306 	/*
307 	 * Free any resources we've allocated during the failed attach
308 	 * attempt.  Do this in reverse order and fall through.
309 	 */
310 fail_5:
311 	for (i = 0; i < GEM_NRXDESC; i++) {
312 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
313 			bus_dmamap_destroy(sc->sc_dmatag,
314 			    sc->sc_rxsoft[i].rxs_dmamap);
315 	}
316 fail_4:
317 	for (i = 0; i < GEM_TXQUEUELEN; i++) {
318 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
319 			bus_dmamap_destroy(sc->sc_dmatag,
320 			    sc->sc_txsoft[i].txs_dmamap);
321 	}
322 	bus_dmamap_unload(sc->sc_dmatag, sc->sc_cddmamap);
323 fail_3:
324 	bus_dmamem_free(sc->sc_cdmatag, sc->sc_control_data,
325 	    sc->sc_cddmamap);
326 fail_2:
327 	bus_dma_tag_destroy(sc->sc_cdmatag);
328 fail_1:
329 	bus_dma_tag_destroy(sc->sc_dmatag);
330 fail_0:
331 	bus_dma_tag_destroy(sc->sc_pdmatag);
332 	return (error);
333 }
334 
335 static void
336 gem_cddma_callback(xsc, segs, nsegs, error)
337 	void *xsc;
338 	bus_dma_segment_t *segs;
339 	int nsegs;
340 	int error;
341 {
342 	struct gem_softc *sc = (struct gem_softc *)xsc;
343 
344 	if (error != 0)
345 		return;
346 	if (nsegs != 1) {
347 		/* can't happen... */
348 		panic("gem_cddma_callback: bad control buffer segment count");
349 	}
350 	sc->sc_cddma = segs[0].ds_addr;
351 }
352 
353 static void
354 gem_rxdma_callback(xsc, segs, nsegs, error)
355 	void *xsc;
356 	bus_dma_segment_t *segs;
357 	int nsegs;
358 	int error;
359 {
360 	struct gem_rxsoft *rxs = (struct gem_rxsoft *)xsc;
361 
362 	if (error != 0)
363 		return;
364 	if (nsegs != 1) {
365 		/* can't happen... */
366 		panic("gem_rxdma_callback: bad control buffer segment count");
367 	}
368 	rxs->rxs_paddr = segs[0].ds_addr;
369 }
370 
371 /*
372  * This is called multiple times in our version of dmamap_load_mbuf, but should
373  * be fit for a generic version that only calls it once.
374  */
375 static void
376 gem_txdma_callback(xsc, segs, nsegs, error)
377 	void *xsc;
378 	bus_dma_segment_t *segs;
379 	int nsegs;
380 	int error;
381 {
382 	struct gem_txdma *tx = (struct gem_txdma *)xsc;
383 	int seg;
384 
385 	tx->txd_error = error;
386 	if (error != 0)
387 		return;
388 	tx->txd_nsegs = nsegs;
389 
390 	/*
391 	 * Initialize the transmit descriptors.
392 	 */
393 	for (seg = 0; seg < nsegs;
394 	     seg++, tx->txd_nexttx = GEM_NEXTTX(tx->txd_nexttx)) {
395 		uint64_t flags;
396 
397 		DPRINTF(tx->txd_sc, ("txdma_cb: mapping seg %d (txd %d), len "
398 		    "%lx, addr %#lx (%#lx)\n",  seg, tx->txd_nexttx,
399 		    segs[seg].ds_len, segs[seg].ds_addr,
400 		    GEM_DMA_WRITE(tx->txd_sc, segs[seg].ds_addr)));
401 		CTR5(KTR_GEM, "txdma_cb: mapping seg %d (txd %d), len "
402 		    "%lx, addr %#lx (%#lx)",  seg, tx->txd_nexttx,
403 		    segs[seg].ds_len, segs[seg].ds_addr,
404 		    GEM_DMA_WRITE(tx->txd_sc, segs[seg].ds_addr));
405 		/*
406 		 * If this is the first descriptor we're
407 		 * enqueueing, set the start of packet flag,
408 		 * and the checksum stuff if we want the hardware
409 		 * to do it.
410 		 */
411 		tx->txd_sc->sc_txdescs[tx->txd_nexttx].gd_addr =
412 		    GEM_DMA_WRITE(tx->txd_sc, segs[seg].ds_addr);
413 		flags = segs[seg].ds_len & GEM_TD_BUFSIZE;
414 		if ((tx->txd_flags & GTXD_FIRST) != 0 && seg == 0) {
415 			CTR2(KTR_GEM, "txdma_cb: start of packet at seg %d, "
416 			    "tx %d", seg, tx->txd_nexttx);
417 			flags |= GEM_TD_START_OF_PACKET;
418 		}
419 		if ((tx->txd_flags & GTXD_LAST) != 0 && seg == nsegs - 1) {
420 			CTR2(KTR_GEM, "txdma_cb: end of packet at seg %d, "
421 			    "tx %d", seg, tx->txd_nexttx);
422 			flags |= GEM_TD_END_OF_PACKET;
423 		}
424 		tx->txd_sc->sc_txdescs[tx->txd_nexttx].gd_flags =
425 		    GEM_DMA_WRITE(tx->txd_sc, flags);
426 		tx->txd_lasttx = tx->txd_nexttx;
427 	}
428 }
429 
430 static void
431 gem_tick(arg)
432 	void *arg;
433 {
434 	struct gem_softc *sc = arg;
435 	int s;
436 
437 	s = splnet();
438 	mii_tick(sc->sc_mii);
439 	splx(s);
440 
441 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
442 }
443 
444 static int
445 gem_bitwait(sc, r, clr, set)
446 	struct gem_softc *sc;
447 	bus_addr_t r;
448 	u_int32_t clr;
449 	u_int32_t set;
450 {
451 	int i;
452 	u_int32_t reg;
453 
454 	for (i = TRIES; i--; DELAY(100)) {
455 		reg = bus_space_read_4(sc->sc_bustag, sc->sc_h, r);
456 		if ((r & clr) == 0 && (r & set) == set)
457 			return (1);
458 	}
459 	return (0);
460 }
461 
462 void
463 gem_reset(sc)
464 	struct gem_softc *sc;
465 {
466 	bus_space_tag_t t = sc->sc_bustag;
467 	bus_space_handle_t h = sc->sc_h;
468 	int s;
469 
470 	s = splnet();
471 	DPRINTF(sc, ("%s: gem_reset\n", device_get_name(sc->sc_dev)));
472 	CTR1(KTR_GEM, "%s: gem_reset", device_get_name(sc->sc_dev));
473 	gem_reset_rx(sc);
474 	gem_reset_tx(sc);
475 
476 	/* Do a full reset */
477 	bus_space_write_4(t, h, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX);
478 	if (!gem_bitwait(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX, 0))
479 		device_printf(sc->sc_dev, "cannot reset device\n");
480 	splx(s);
481 }
482 
483 
484 /*
485  * gem_rxdrain:
486  *
487  *	Drain the receive queue.
488  */
489 static void
490 gem_rxdrain(sc)
491 	struct gem_softc *sc;
492 {
493 	struct gem_rxsoft *rxs;
494 	int i;
495 
496 	for (i = 0; i < GEM_NRXDESC; i++) {
497 		rxs = &sc->sc_rxsoft[i];
498 		if (rxs->rxs_mbuf != NULL) {
499 			bus_dmamap_unload(sc->sc_dmatag, rxs->rxs_dmamap);
500 			m_freem(rxs->rxs_mbuf);
501 			rxs->rxs_mbuf = NULL;
502 		}
503 	}
504 }
505 
506 /*
507  * Reset the whole thing.
508  */
509 static void
510 gem_stop(ifp, disable)
511 	struct ifnet *ifp;
512 	int disable;
513 {
514 	struct gem_softc *sc = (struct gem_softc *)ifp->if_softc;
515 	struct gem_txsoft *txs;
516 
517 	DPRINTF(sc, ("%s: gem_stop\n", device_get_name(sc->sc_dev)));
518 	CTR1(KTR_GEM, "%s: gem_stop", device_get_name(sc->sc_dev));
519 
520 	callout_stop(&sc->sc_tick_ch);
521 
522 	/* XXX - Should we reset these instead? */
523 	gem_disable_tx(sc);
524 	gem_disable_rx(sc);
525 
526 	/*
527 	 * Release any queued transmit buffers.
528 	 */
529 	while ((txs = STAILQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
530 		STAILQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
531 		if (txs->txs_ndescs != 0) {
532 			bus_dmamap_unload(sc->sc_dmatag, txs->txs_dmamap);
533 			if (txs->txs_mbuf != NULL) {
534 				m_freem(txs->txs_mbuf);
535 				txs->txs_mbuf = NULL;
536 			}
537 		}
538 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
539 	}
540 
541 	if (disable)
542 		gem_rxdrain(sc);
543 
544 	/*
545 	 * Mark the interface down and cancel the watchdog timer.
546 	 */
547 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
548 	ifp->if_timer = 0;
549 }
550 
551 /*
552  * Reset the receiver
553  */
554 int
555 gem_reset_rx(sc)
556 	struct gem_softc *sc;
557 {
558 	bus_space_tag_t t = sc->sc_bustag;
559 	bus_space_handle_t h = sc->sc_h;
560 
561 	/*
562 	 * Resetting while DMA is in progress can cause a bus hang, so we
563 	 * disable DMA first.
564 	 */
565 	gem_disable_rx(sc);
566 	bus_space_write_4(t, h, GEM_RX_CONFIG, 0);
567 	/* Wait till it finishes */
568 	if (!gem_bitwait(sc, GEM_RX_CONFIG, 1, 0))
569 		device_printf(sc->sc_dev, "cannot disable read dma\n");
570 
571 	/* Wait 5ms extra. */
572 	DELAY(5000);
573 
574 	/* Finally, reset the ERX */
575 	bus_space_write_4(t, h, GEM_RESET, GEM_RESET_RX);
576 	/* Wait till it finishes */
577 	if (!gem_bitwait(sc, GEM_RESET, GEM_RESET_TX, 0)) {
578 		device_printf(sc->sc_dev, "cannot reset receiver\n");
579 		return (1);
580 	}
581 	return (0);
582 }
583 
584 
585 /*
586  * Reset the transmitter
587  */
588 static int
589 gem_reset_tx(sc)
590 	struct gem_softc *sc;
591 {
592 	bus_space_tag_t t = sc->sc_bustag;
593 	bus_space_handle_t h = sc->sc_h;
594 	int i;
595 
596 	/*
597 	 * Resetting while DMA is in progress can cause a bus hang, so we
598 	 * disable DMA first.
599 	 */
600 	gem_disable_tx(sc);
601 	bus_space_write_4(t, h, GEM_TX_CONFIG, 0);
602 	/* Wait till it finishes */
603 	if (!gem_bitwait(sc, GEM_TX_CONFIG, 1, 0))
604 		device_printf(sc->sc_dev, "cannot disable read dma\n");
605 
606 	/* Wait 5ms extra. */
607 	DELAY(5000);
608 
609 	/* Finally, reset the ETX */
610 	bus_space_write_4(t, h, GEM_RESET, GEM_RESET_TX);
611 	/* Wait till it finishes */
612 	for (i = TRIES; i--; DELAY(100))
613 		if ((bus_space_read_4(t, h, GEM_RESET) & GEM_RESET_TX) == 0)
614 			break;
615 	if (!gem_bitwait(sc, GEM_RESET, GEM_RESET_TX, 0)) {
616 		device_printf(sc->sc_dev, "cannot reset receiver\n");
617 		return (1);
618 	}
619 	return (0);
620 }
621 
622 /*
623  * disable receiver.
624  */
625 static int
626 gem_disable_rx(sc)
627 	struct gem_softc *sc;
628 {
629 	bus_space_tag_t t = sc->sc_bustag;
630 	bus_space_handle_t h = sc->sc_h;
631 	u_int32_t cfg;
632 
633 	/* Flip the enable bit */
634 	cfg = bus_space_read_4(t, h, GEM_MAC_RX_CONFIG);
635 	cfg &= ~GEM_MAC_RX_ENABLE;
636 	bus_space_write_4(t, h, GEM_MAC_RX_CONFIG, cfg);
637 
638 	/* Wait for it to finish */
639 	return (gem_bitwait(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_ENABLE, 0));
640 }
641 
642 /*
643  * disable transmitter.
644  */
645 static int
646 gem_disable_tx(sc)
647 	struct gem_softc *sc;
648 {
649 	bus_space_tag_t t = sc->sc_bustag;
650 	bus_space_handle_t h = sc->sc_h;
651 	u_int32_t cfg;
652 
653 	/* Flip the enable bit */
654 	cfg = bus_space_read_4(t, h, GEM_MAC_TX_CONFIG);
655 	cfg &= ~GEM_MAC_TX_ENABLE;
656 	bus_space_write_4(t, h, GEM_MAC_TX_CONFIG, cfg);
657 
658 	/* Wait for it to finish */
659 	return (gem_bitwait(sc, GEM_MAC_TX_CONFIG, GEM_MAC_TX_ENABLE, 0));
660 }
661 
662 /*
663  * Initialize interface.
664  */
665 static int
666 gem_meminit(sc)
667 	struct gem_softc *sc;
668 {
669 	struct gem_rxsoft *rxs;
670 	int i, error;
671 
672 	/*
673 	 * Initialize the transmit descriptor ring.
674 	 */
675 	memset((void *)sc->sc_txdescs, 0, sizeof(sc->sc_txdescs));
676 	for (i = 0; i < GEM_NTXDESC; i++) {
677 		sc->sc_txdescs[i].gd_flags = 0;
678 		sc->sc_txdescs[i].gd_addr = 0;
679 	}
680 	GEM_CDTXSYNC(sc, 0, GEM_NTXDESC,
681 	    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
682 	sc->sc_txfree = GEM_NTXDESC;
683 	sc->sc_txnext = 0;
684 
685 	/*
686 	 * Initialize the receive descriptor and receive job
687 	 * descriptor rings.
688 	 */
689 	for (i = 0; i < GEM_NRXDESC; i++) {
690 		rxs = &sc->sc_rxsoft[i];
691 		if (rxs->rxs_mbuf == NULL) {
692 			if ((error = gem_add_rxbuf(sc, i)) != 0) {
693 				device_printf(sc->sc_dev, "unable to "
694 				    "allocate or map rx buffer %d, error = "
695 				    "%d\n", i, error);
696 				/*
697 				 * XXX Should attempt to run with fewer receive
698 				 * XXX buffers instead of just failing.
699 				 */
700 				gem_rxdrain(sc);
701 				return (1);
702 			}
703 		} else
704 			GEM_INIT_RXDESC(sc, i);
705 	}
706 	sc->sc_rxptr = 0;
707 
708 	return (0);
709 }
710 
711 static int
712 gem_ringsize(sz)
713 	int sz;
714 {
715 	int v = 0;
716 
717 	switch (sz) {
718 	case 32:
719 		v = GEM_RING_SZ_32;
720 		break;
721 	case 64:
722 		v = GEM_RING_SZ_64;
723 		break;
724 	case 128:
725 		v = GEM_RING_SZ_128;
726 		break;
727 	case 256:
728 		v = GEM_RING_SZ_256;
729 		break;
730 	case 512:
731 		v = GEM_RING_SZ_512;
732 		break;
733 	case 1024:
734 		v = GEM_RING_SZ_1024;
735 		break;
736 	case 2048:
737 		v = GEM_RING_SZ_2048;
738 		break;
739 	case 4096:
740 		v = GEM_RING_SZ_4096;
741 		break;
742 	case 8192:
743 		v = GEM_RING_SZ_8192;
744 		break;
745 	default:
746 		printf("gem: invalid Receive Descriptor ring size\n");
747 		break;
748 	}
749 	return (v);
750 }
751 
752 /*
753  * Initialization of interface; set up initialization block
754  * and transmit/receive descriptor rings.
755  */
756 static void
757 gem_init(xsc)
758 	void *xsc;
759 {
760 	struct gem_softc *sc = (struct gem_softc *)xsc;
761 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
762 	bus_space_tag_t t = sc->sc_bustag;
763 	bus_space_handle_t h = sc->sc_h;
764 	int s;
765 	u_int32_t v;
766 
767 	s = splnet();
768 
769 	DPRINTF(sc, ("%s: gem_init: calling stop\n", device_get_name(sc->sc_dev)));
770 	CTR1(KTR_GEM, "%s: gem_init: calling stop", device_get_name(sc->sc_dev));
771 	/*
772 	 * Initialization sequence. The numbered steps below correspond
773 	 * to the sequence outlined in section 6.3.5.1 in the Ethernet
774 	 * Channel Engine manual (part of the PCIO manual).
775 	 * See also the STP2002-STQ document from Sun Microsystems.
776 	 */
777 
778 	/* step 1 & 2. Reset the Ethernet Channel */
779 	gem_stop(&sc->sc_arpcom.ac_if, 0);
780 	gem_reset(sc);
781 	DPRINTF(sc, ("%s: gem_init: restarting\n", device_get_name(sc->sc_dev)));
782 	CTR1(KTR_GEM, "%s: gem_init: restarting", device_get_name(sc->sc_dev));
783 
784 	/* Re-initialize the MIF */
785 	gem_mifinit(sc);
786 
787 	/* Call MI reset function if any */
788 	if (sc->sc_hwreset)
789 		(*sc->sc_hwreset)(sc);
790 
791 	/* step 3. Setup data structures in host memory */
792 	gem_meminit(sc);
793 
794 	/* step 4. TX MAC registers & counters */
795 	gem_init_regs(sc);
796 	/* XXX: VLAN code from NetBSD temporarily removed. */
797 	bus_space_write_4(t, h, GEM_MAC_MAC_MAX_FRAME,
798             (ETHER_MAX_LEN + sizeof(struct ether_header)) | (0x2000<<16));
799 
800 	/* step 5. RX MAC registers & counters */
801 	gem_setladrf(sc);
802 
803 	/* step 6 & 7. Program Descriptor Ring Base Addresses */
804 	/* NOTE: we use only 32-bit DMA addresses here. */
805 	bus_space_write_4(t, h, GEM_TX_RING_PTR_HI, 0);
806 	bus_space_write_4(t, h, GEM_TX_RING_PTR_LO, GEM_CDTXADDR(sc, 0));
807 
808 	bus_space_write_4(t, h, GEM_RX_RING_PTR_HI, 0);
809 	bus_space_write_4(t, h, GEM_RX_RING_PTR_LO, GEM_CDRXADDR(sc, 0));
810 	DPRINTF(sc, ("loading rx ring %lx, tx ring %lx, cddma %lx\n",
811 	    GEM_CDRXADDR(sc, 0), GEM_CDTXADDR(sc, 0), sc->sc_cddma));
812 	CTR3(KTR_GEM, "loading rx ring %lx, tx ring %lx, cddma %lx",
813 	    GEM_CDRXADDR(sc, 0), GEM_CDTXADDR(sc, 0), sc->sc_cddma);
814 
815 	/* step 8. Global Configuration & Interrupt Mask */
816 	bus_space_write_4(t, h, GEM_INTMASK,
817 		      ~(GEM_INTR_TX_INTME|
818 			GEM_INTR_TX_EMPTY|
819 			GEM_INTR_RX_DONE|GEM_INTR_RX_NOBUF|
820 			GEM_INTR_RX_TAG_ERR|GEM_INTR_PCS|
821 			GEM_INTR_MAC_CONTROL|GEM_INTR_MIF|
822 			GEM_INTR_BERR));
823 	bus_space_write_4(t, h, GEM_MAC_RX_MASK, 0); /* XXXX */
824 	bus_space_write_4(t, h, GEM_MAC_TX_MASK, 0xffff); /* XXXX */
825 	bus_space_write_4(t, h, GEM_MAC_CONTROL_MASK, 0); /* XXXX */
826 
827 	/* step 9. ETX Configuration: use mostly default values */
828 
829 	/* Enable DMA */
830 	v = gem_ringsize(GEM_NTXDESC /*XXX*/);
831 	bus_space_write_4(t, h, GEM_TX_CONFIG,
832 		v|GEM_TX_CONFIG_TXDMA_EN|
833 		((0x400<<10)&GEM_TX_CONFIG_TXFIFO_TH));
834 
835 	/* step 10. ERX Configuration */
836 
837 	/* Encode Receive Descriptor ring size: four possible values */
838 	v = gem_ringsize(GEM_NRXDESC /*XXX*/);
839 
840 	/* Enable DMA */
841 	bus_space_write_4(t, h, GEM_RX_CONFIG,
842 		v|(GEM_THRSH_1024<<GEM_RX_CONFIG_FIFO_THRS_SHIFT)|
843 		(2<<GEM_RX_CONFIG_FBOFF_SHFT)|GEM_RX_CONFIG_RXDMA_EN|
844 		(0<<GEM_RX_CONFIG_CXM_START_SHFT));
845 	/*
846 	 * The following value is for an OFF Threshold of about 15.5 Kbytes
847 	 * and an ON Threshold of 4K bytes.
848 	 */
849 	bus_space_write_4(t, h, GEM_RX_PAUSE_THRESH, 0xf8 | (0x40 << 12));
850 	bus_space_write_4(t, h, GEM_RX_BLANKING, (2<<12)|6);
851 
852 	/* step 11. Configure Media */
853 	(void)gem_mii_statchg(sc->sc_dev);
854 
855 	/* step 12. RX_MAC Configuration Register */
856 	v = bus_space_read_4(t, h, GEM_MAC_RX_CONFIG);
857 	v |= GEM_MAC_RX_ENABLE;
858 	bus_space_write_4(t, h, GEM_MAC_RX_CONFIG, v);
859 
860 	/* step 14. Issue Transmit Pending command */
861 
862 	/* Call MI initialization function if any */
863 	if (sc->sc_hwinit)
864 		(*sc->sc_hwinit)(sc);
865 
866 	/* step 15.  Give the reciever a swift kick */
867 	bus_space_write_4(t, h, GEM_RX_KICK, GEM_NRXDESC-4);
868 
869 	/* Start the one second timer. */
870 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
871 
872 	ifp->if_flags |= IFF_RUNNING;
873 	ifp->if_flags &= ~IFF_OACTIVE;
874 	ifp->if_timer = 0;
875 	sc->sc_flags = ifp->if_flags;
876 	splx(s);
877 }
878 
879 /*
880  * XXX: This is really a substitute for bus_dmamap_load_mbuf(), which FreeBSD
881  * does not yet have, with some adaptions for this driver.
882  * Some changes are mandated by the fact that multiple maps may needed to map
883  * a single mbuf.
884  * It should be removed once generic support is available.
885  *
886  * This is derived from NetBSD (syssrc/sys/arch/sparc64/sparc64/machdep.c), for
887  * a copyright notice see sparc64/sparc64/bus_machdep.c.
888  *
889  * Not every error condition is passed to the callback in this version, and the
890  * callback may be called more than once.
891  * It also gropes in the entails of the callback arg...
892  */
893 static int
894 gem_dmamap_load_mbuf(sc, m0, cb, txj, flags)
895 	struct gem_softc *sc;
896 	struct mbuf *m0;
897 	bus_dmamap_callback_t *cb;
898 	struct gem_txjob *txj;
899 	int flags;
900 {
901 	struct gem_txdma txd;
902 	struct gem_txsoft *txs;
903 	struct mbuf *m;
904 	void  *vaddr;
905 	int error, first = 1, len, totlen;
906 
907 	if ((m0->m_flags & M_PKTHDR) == 0)
908 		panic("gem_dmamap_load_mbuf: no packet header");
909 	totlen = m0->m_pkthdr.len;
910 	len = 0;
911 	txd.txd_sc = sc;
912 	txd.txd_nexttx = txj->txj_nexttx;
913 	txj->txj_nsegs = 0;
914 	STAILQ_INIT(&txj->txj_txsq);
915 	m = m0;
916 	while (m != NULL && len < totlen) {
917 		if (m->m_len == 0)
918 			continue;
919 		/* Get a work queue entry. */
920 		if ((txs = STAILQ_FIRST(&sc->sc_txfreeq)) == NULL) {
921 			/*
922 			 * Ran out of descriptors, return a value that
923 			 * cannot be returned by bus_dmamap_load to notify
924 			 * the caller.
925 			 */
926 			error = -1;
927 			goto fail;
928 		}
929 		len += m->m_len;
930 		txd.txd_flags = first ? GTXD_FIRST : 0;
931 		if (m->m_next == NULL || len >= totlen)
932 			txd.txd_flags |= GTXD_LAST;
933 		vaddr = mtod(m, void *);
934 		error = bus_dmamap_load(sc->sc_dmatag, txs->txs_dmamap, vaddr,
935 		    m->m_len, cb, &txd, flags);
936 		if (error != 0 || txd.txd_error != 0)
937 			goto fail;
938 		/* Sync the DMA map. */
939 		bus_dmamap_sync(sc->sc_dmatag, txs->txs_dmamap,
940 		    BUS_DMASYNC_PREWRITE);
941 		m = m->m_next;
942 		/*
943 		 * Store a pointer to the packet so we can free it later,
944 		 * and remember what txdirty will be once the packet is
945 		 * done.
946 		 */
947 		txs->txs_mbuf = first ? m0 : NULL;
948 		txs->txs_firstdesc = txj->txj_nexttx;
949 		txs->txs_lastdesc = txd.txd_lasttx;
950 		txs->txs_ndescs = txd.txd_nsegs;
951 		CTR3(KTR_GEM, "load_mbuf: setting firstdesc=%d, lastdesc=%d, "
952 		    "ndescs=%d", txs->txs_firstdesc, txs->txs_lastdesc,
953 		    txs->txs_ndescs);
954 		STAILQ_REMOVE_HEAD(&sc->sc_txfreeq, txs_q);
955 		STAILQ_INSERT_TAIL(&txj->txj_txsq, txs, txs_q);
956 		txj->txj_nexttx = txd.txd_nexttx;
957 		txj->txj_nsegs += txd.txd_nsegs;
958 		first = 0;
959 	}
960 	txj->txj_lasttx = txd.txd_lasttx;
961 	return (0);
962 
963 fail:
964 	CTR1(KTR_GEM, "gem_dmamap_load_mbuf failed (%d)", error);
965 	gem_dmamap_unload_mbuf(sc, txj);
966 	return (error);
967 }
968 
969 /*
970  * Unload an mbuf using the txd the information was placed in.
971  * The tx interrupt code frees the tx segments one by one, because the txd is
972  * not available any more.
973  */
974 static void
975 gem_dmamap_unload_mbuf(sc, txj)
976 	struct gem_softc *sc;
977 	struct gem_txjob *txj;
978 {
979 	struct gem_txsoft *txs;
980 
981 	/* Readd the removed descriptors and unload the segments. */
982 	while ((txs = STAILQ_FIRST(&txj->txj_txsq)) != NULL) {
983 		bus_dmamap_unload(sc->sc_dmatag, txs->txs_dmamap);
984 		STAILQ_REMOVE_HEAD(&txj->txj_txsq, txs_q);
985 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
986 	}
987 }
988 
989 static void
990 gem_dmamap_commit_mbuf(sc, txj)
991 	struct gem_softc *sc;
992 	struct gem_txjob *txj;
993 {
994 	struct gem_txsoft *txs;
995 
996 	/* Commit the txjob by transfering the txsoft's to the txdirtyq. */
997 	while ((txs = STAILQ_FIRST(&txj->txj_txsq)) != NULL) {
998 		STAILQ_REMOVE_HEAD(&txj->txj_txsq, txs_q);
999 		STAILQ_INSERT_TAIL(&sc->sc_txdirtyq, txs, txs_q);
1000 	}
1001 }
1002 
1003 static void
1004 gem_init_regs(sc)
1005 	struct gem_softc *sc;
1006 {
1007 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1008 	bus_space_tag_t t = sc->sc_bustag;
1009 	bus_space_handle_t h = sc->sc_h;
1010 
1011 	/* These regs are not cleared on reset */
1012 	sc->sc_inited = 0;
1013 	if (!sc->sc_inited) {
1014 
1015 		/* Wooo.  Magic values. */
1016 		bus_space_write_4(t, h, GEM_MAC_IPG0, 0);
1017 		bus_space_write_4(t, h, GEM_MAC_IPG1, 8);
1018 		bus_space_write_4(t, h, GEM_MAC_IPG2, 4);
1019 
1020 		bus_space_write_4(t, h, GEM_MAC_MAC_MIN_FRAME, ETHER_MIN_LEN);
1021 		/* Max frame and max burst size */
1022 		bus_space_write_4(t, h, GEM_MAC_MAC_MAX_FRAME,
1023 			(ifp->if_mtu+18) | (0x2000<<16)/* Burst size */);
1024 		bus_space_write_4(t, h, GEM_MAC_PREAMBLE_LEN, 0x7);
1025 		bus_space_write_4(t, h, GEM_MAC_JAM_SIZE, 0x4);
1026 		bus_space_write_4(t, h, GEM_MAC_ATTEMPT_LIMIT, 0x10);
1027 		/* Dunno.... */
1028 		bus_space_write_4(t, h, GEM_MAC_CONTROL_TYPE, 0x8088);
1029 		bus_space_write_4(t, h, GEM_MAC_RANDOM_SEED,
1030 			((sc->sc_arpcom.ac_enaddr[5]<<8)|
1031 			  sc->sc_arpcom.ac_enaddr[4])&0x3ff);
1032 		/* Secondary MAC addr set to 0:0:0:0:0:0 */
1033 		bus_space_write_4(t, h, GEM_MAC_ADDR3, 0);
1034 		bus_space_write_4(t, h, GEM_MAC_ADDR4, 0);
1035 		bus_space_write_4(t, h, GEM_MAC_ADDR5, 0);
1036 		/* MAC control addr set to 0:1:c2:0:1:80 */
1037 		bus_space_write_4(t, h, GEM_MAC_ADDR6, 0x0001);
1038 		bus_space_write_4(t, h, GEM_MAC_ADDR7, 0xc200);
1039 		bus_space_write_4(t, h, GEM_MAC_ADDR8, 0x0180);
1040 
1041 		/* MAC filter addr set to 0:0:0:0:0:0 */
1042 		bus_space_write_4(t, h, GEM_MAC_ADDR_FILTER0, 0);
1043 		bus_space_write_4(t, h, GEM_MAC_ADDR_FILTER1, 0);
1044 		bus_space_write_4(t, h, GEM_MAC_ADDR_FILTER2, 0);
1045 
1046 		bus_space_write_4(t, h, GEM_MAC_ADR_FLT_MASK1_2, 0);
1047 		bus_space_write_4(t, h, GEM_MAC_ADR_FLT_MASK0, 0);
1048 
1049 		sc->sc_inited = 1;
1050 	}
1051 
1052 	/* Counters need to be zeroed */
1053 	bus_space_write_4(t, h, GEM_MAC_NORM_COLL_CNT, 0);
1054 	bus_space_write_4(t, h, GEM_MAC_FIRST_COLL_CNT, 0);
1055 	bus_space_write_4(t, h, GEM_MAC_EXCESS_COLL_CNT, 0);
1056 	bus_space_write_4(t, h, GEM_MAC_LATE_COLL_CNT, 0);
1057 	bus_space_write_4(t, h, GEM_MAC_DEFER_TMR_CNT, 0);
1058 	bus_space_write_4(t, h, GEM_MAC_PEAK_ATTEMPTS, 0);
1059 	bus_space_write_4(t, h, GEM_MAC_RX_FRAME_COUNT, 0);
1060 	bus_space_write_4(t, h, GEM_MAC_RX_LEN_ERR_CNT, 0);
1061 	bus_space_write_4(t, h, GEM_MAC_RX_ALIGN_ERR, 0);
1062 	bus_space_write_4(t, h, GEM_MAC_RX_CRC_ERR_CNT, 0);
1063 	bus_space_write_4(t, h, GEM_MAC_RX_CODE_VIOL, 0);
1064 
1065 	/* Un-pause stuff */
1066 #if 0
1067 	bus_space_write_4(t, h, GEM_MAC_SEND_PAUSE_CMD, 0x1BF0);
1068 #else
1069 	bus_space_write_4(t, h, GEM_MAC_SEND_PAUSE_CMD, 0);
1070 #endif
1071 
1072 	/*
1073 	 * Set the station address.
1074 	 */
1075 	bus_space_write_4(t, h, GEM_MAC_ADDR0,
1076 		(sc->sc_arpcom.ac_enaddr[4]<<8) | sc->sc_arpcom.ac_enaddr[5]);
1077 	bus_space_write_4(t, h, GEM_MAC_ADDR1,
1078 		(sc->sc_arpcom.ac_enaddr[2]<<8) | sc->sc_arpcom.ac_enaddr[3]);
1079 	bus_space_write_4(t, h, GEM_MAC_ADDR2,
1080 		(sc->sc_arpcom.ac_enaddr[0]<<8) | sc->sc_arpcom.ac_enaddr[1]);
1081 }
1082 
1083 static void
1084 gem_start(ifp)
1085 	struct ifnet *ifp;
1086 {
1087 	struct gem_softc *sc = (struct gem_softc *)ifp->if_softc;
1088 	struct mbuf *m0 = NULL, *m;
1089 	struct gem_txjob txj;
1090 	int firsttx, ofree, seg, ntx, txmfail;
1091 
1092 	if ((ifp->if_flags & (IFF_RUNNING | IFF_OACTIVE)) != IFF_RUNNING)
1093 		return;
1094 
1095 	/*
1096 	 * Remember the previous number of free descriptors and
1097 	 * the first descriptor we'll use.
1098 	 */
1099 	ofree = sc->sc_txfree;
1100 	firsttx = sc->sc_txnext;
1101 
1102 	DPRINTF(sc, ("%s: gem_start: txfree %d, txnext %d\n",
1103 	    device_get_name(sc->sc_dev), ofree, firsttx));
1104 	CTR3(KTR_GEM, "%s: gem_start: txfree %d, txnext %d",
1105 	    device_get_name(sc->sc_dev), ofree, firsttx);
1106 
1107 	txj.txj_nexttx = firsttx;
1108 	txj.txj_lasttx = 0;
1109 	/*
1110 	 * Loop through the send queue, setting up transmit descriptors
1111 	 * until we drain the queue, or use up all available transmit
1112 	 * descriptors.
1113 	 */
1114 	txmfail = 0;
1115 	for (ntx = 0;; ntx++) {
1116 		/*
1117 		 * Grab a packet off the queue.
1118 		 */
1119 		IF_DEQUEUE(&ifp->if_snd, m0);
1120 		if (m0 == NULL)
1121 			break;
1122 		m = NULL;
1123 
1124 		/*
1125 		 * Load the DMA map.  If this fails, the packet either
1126 		 * didn't fit in the alloted number of segments, or we were
1127 		 * short on resources.  In this case, we'll copy and try
1128 		 * again.
1129 		 */
1130 		txmfail = gem_dmamap_load_mbuf(sc, m0,
1131 		    gem_txdma_callback, &txj, BUS_DMA_NOWAIT);
1132 		if (txmfail == -1) {
1133 			IF_PREPEND(&ifp->if_snd, m0);
1134 			break;
1135 		}
1136 		if (txmfail > 0) {
1137 			MGETHDR(m, M_DONTWAIT, MT_DATA);
1138 			if (m == NULL) {
1139 				device_printf(sc->sc_dev, "unable to "
1140 				    "allocate Tx mbuf\n");
1141 				/* Failed; requeue. */
1142 				IF_PREPEND(&ifp->if_snd, m0);
1143 				break;
1144 			}
1145 			if (m0->m_pkthdr.len > MHLEN) {
1146 				MCLGET(m, M_DONTWAIT);
1147 				if ((m->m_flags & M_EXT) == 0) {
1148 					device_printf(sc->sc_dev, "unable to "
1149 					    "allocate Tx cluster\n");
1150 					IF_PREPEND(&ifp->if_snd, m0);
1151 					m_freem(m);
1152 					break;
1153 				}
1154 			}
1155 			m_copydata(m0, 0, m0->m_pkthdr.len, mtod(m, caddr_t));
1156 			m->m_pkthdr.len = m->m_len = m0->m_pkthdr.len;
1157 			txmfail = gem_dmamap_load_mbuf(sc, m,
1158 			    gem_txdma_callback, &txj, BUS_DMA_NOWAIT);
1159 			if (txmfail != 0) {
1160 				if (txmfail > 0) {
1161 					device_printf(sc->sc_dev, "unable to "
1162 					    "load Tx buffer, error = %d\n",
1163 					    txmfail);
1164 				}
1165 				m_freem(m);
1166 				IF_PREPEND(&ifp->if_snd, m0);
1167 				break;
1168 			}
1169 		}
1170 
1171 		/*
1172 		 * Ensure we have enough descriptors free to describe
1173 		 * the packet.  Note, we always reserve one descriptor
1174 		 * at the end of the ring as a termination point, to
1175 		 * prevent wrap-around.
1176 		 */
1177 		if (txj.txj_nsegs > (sc->sc_txfree - 1)) {
1178 			/*
1179 			 * Not enough free descriptors to transmit this
1180 			 * packet.  We haven't committed to anything yet,
1181 			 * so just unload the DMA map, put the packet
1182 			 * back on the queue, and punt.  Notify the upper
1183 			 * layer that there are no more slots left.
1184 			 *
1185 			 * XXX We could allocate an mbuf and copy, but
1186 			 * XXX it is worth it?
1187 			 */
1188 			ifp->if_flags |= IFF_OACTIVE;
1189 			gem_dmamap_unload_mbuf(sc, &txj);
1190 			if (m != NULL)
1191 				m_freem(m);
1192 			IF_PREPEND(&ifp->if_snd, m0);
1193 			break;
1194 		}
1195 
1196 		if (m != NULL)
1197 			m_freem(m0);
1198 
1199 		/*
1200 		 * WE ARE NOW COMMITTED TO TRANSMITTING THE PACKET.
1201 		 */
1202 
1203 #ifdef GEM_DEBUG
1204 		if (ifp->if_flags & IFF_DEBUG) {
1205 			printf("     gem_start %p transmit chain:\n",
1206 			    STAILQ_FIRST(&txj.txj_txsq));
1207 			for (seg = sc->sc_txnext;; seg = GEM_NEXTTX(seg)) {
1208 				printf("descriptor %d:\t", seg);
1209 				printf("gd_flags:   0x%016llx\t", (long long)
1210 					GEM_DMA_READ(sc, sc->sc_txdescs[seg].gd_flags));
1211 				printf("gd_addr: 0x%016llx\n", (long long)
1212 					GEM_DMA_READ(sc, sc->sc_txdescs[seg].gd_addr));
1213 				if (seg == txj.txj_lasttx)
1214 					break;
1215 			}
1216 		}
1217 #endif
1218 
1219 		/* Sync the descriptors we're using. */
1220 		GEM_CDTXSYNC(sc, sc->sc_txnext, txj.txj_nsegs,
1221 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
1222 
1223 		/* Advance the tx pointer. */
1224 		sc->sc_txfree -= txj.txj_nsegs;
1225 		sc->sc_txnext = txj.txj_nexttx;
1226 
1227 		gem_dmamap_commit_mbuf(sc, &txj);
1228 	}
1229 
1230 	if (txmfail == -1 || sc->sc_txfree == 0) {
1231 		ifp->if_flags |= IFF_OACTIVE;
1232 		/* No more slots left; notify upper layer. */
1233 	}
1234 
1235 	if (ntx > 0) {
1236 		DPRINTF(sc, ("%s: packets enqueued, IC on %d, OWN on %d\n",
1237 		    device_get_name(sc->sc_dev), txj.txj_lasttx, firsttx));
1238 		CTR3(KTR_GEM, "%s: packets enqueued, IC on %d, OWN on %d",
1239 		    device_get_name(sc->sc_dev), txj.txj_lasttx, firsttx);
1240 		/*
1241 		 * The entire packet chain is set up.
1242 		 * Kick the transmitter.
1243 		 */
1244 		DPRINTF(sc, ("%s: gem_start: kicking tx %d\n",
1245 			device_get_name(sc->sc_dev), txj.txj_nexttx));
1246 		CTR3(KTR_GEM, "%s: gem_start: kicking tx %d=%d",
1247 		    device_get_name(sc->sc_dev), txj.txj_nexttx,
1248 		    sc->sc_txnext);
1249 		bus_space_write_4(sc->sc_bustag, sc->sc_h, GEM_TX_KICK,
1250 			sc->sc_txnext);
1251 
1252 		/* Set a watchdog timer in case the chip flakes out. */
1253 		ifp->if_timer = 5;
1254 		DPRINTF(sc, ("%s: gem_start: watchdog %d\n",
1255 			device_get_name(sc->sc_dev), ifp->if_timer));
1256 		CTR2(KTR_GEM, "%s: gem_start: watchdog %d",
1257 			device_get_name(sc->sc_dev), ifp->if_timer);
1258 	}
1259 }
1260 
1261 /*
1262  * Transmit interrupt.
1263  */
1264 static void
1265 gem_tint(sc)
1266 	struct gem_softc *sc;
1267 {
1268 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1269 	bus_space_tag_t t = sc->sc_bustag;
1270 	bus_space_handle_t mac = sc->sc_h;
1271 	struct gem_txsoft *txs;
1272 	int txlast;
1273 
1274 
1275 	DPRINTF(sc, ("%s: gem_tint\n", device_get_name(sc->sc_dev)));
1276 	CTR1(KTR_GEM, "%s: gem_tint", device_get_name(sc->sc_dev));
1277 
1278 	/*
1279 	 * Unload collision counters
1280 	 */
1281 	ifp->if_collisions +=
1282 		bus_space_read_4(t, mac, GEM_MAC_NORM_COLL_CNT) +
1283 		bus_space_read_4(t, mac, GEM_MAC_FIRST_COLL_CNT) +
1284 		bus_space_read_4(t, mac, GEM_MAC_EXCESS_COLL_CNT) +
1285 		bus_space_read_4(t, mac, GEM_MAC_LATE_COLL_CNT);
1286 
1287 	/*
1288 	 * then clear the hardware counters.
1289 	 */
1290 	bus_space_write_4(t, mac, GEM_MAC_NORM_COLL_CNT, 0);
1291 	bus_space_write_4(t, mac, GEM_MAC_FIRST_COLL_CNT, 0);
1292 	bus_space_write_4(t, mac, GEM_MAC_EXCESS_COLL_CNT, 0);
1293 	bus_space_write_4(t, mac, GEM_MAC_LATE_COLL_CNT, 0);
1294 
1295 	/*
1296 	 * Go through our Tx list and free mbufs for those
1297 	 * frames that have been transmitted.
1298 	 */
1299 	while ((txs = STAILQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
1300 		GEM_CDTXSYNC(sc, txs->txs_lastdesc,
1301 		    txs->txs_ndescs,
1302 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1303 
1304 #ifdef GEM_DEBUG
1305 		if (ifp->if_flags & IFF_DEBUG) {
1306 			int i;
1307 			printf("    txsoft %p transmit chain:\n", txs);
1308 			for (i = txs->txs_firstdesc;; i = GEM_NEXTTX(i)) {
1309 				printf("descriptor %d: ", i);
1310 				printf("gd_flags: 0x%016llx\t", (long long)
1311 					GEM_DMA_READ(sc, sc->sc_txdescs[i].gd_flags));
1312 				printf("gd_addr: 0x%016llx\n", (long long)
1313 					GEM_DMA_READ(sc, sc->sc_txdescs[i].gd_addr));
1314 				if (i == txs->txs_lastdesc)
1315 					break;
1316 			}
1317 		}
1318 #endif
1319 
1320 		/*
1321 		 * In theory, we could harveast some descriptors before
1322 		 * the ring is empty, but that's a bit complicated.
1323 		 *
1324 		 * GEM_TX_COMPLETION points to the last descriptor
1325 		 * processed +1.
1326 		 */
1327 		txlast = bus_space_read_4(t, mac, GEM_TX_COMPLETION);
1328 		DPRINTF(sc,
1329 			("gem_tint: txs->txs_lastdesc = %d, txlast = %d\n",
1330 				txs->txs_lastdesc, txlast));
1331 		CTR3(KTR_GEM, "gem_tint: txs->txs_firstdesc = %d, "
1332 		    "txs->txs_lastdesc = %d, txlast = %d",
1333 		    txs->txs_firstdesc, txs->txs_lastdesc, txlast);
1334 		if (txs->txs_firstdesc <= txs->txs_lastdesc) {
1335 			if ((txlast >= txs->txs_firstdesc) &&
1336 				(txlast <= txs->txs_lastdesc))
1337 				break;
1338 		} else {
1339 			/* Ick -- this command wraps */
1340 			if ((txlast >= txs->txs_firstdesc) ||
1341 				(txlast <= txs->txs_lastdesc))
1342 				break;
1343 		}
1344 
1345 		DPRINTF(sc, ("gem_tint: releasing a desc\n"));
1346 		CTR0(KTR_GEM, "gem_tint: releasing a desc");
1347 		STAILQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
1348 
1349 		sc->sc_txfree += txs->txs_ndescs;
1350 
1351 		bus_dmamap_sync(sc->sc_dmatag, txs->txs_dmamap,
1352 		    BUS_DMASYNC_POSTWRITE);
1353 		bus_dmamap_unload(sc->sc_dmatag, txs->txs_dmamap);
1354 		if (txs->txs_mbuf != NULL) {
1355 			m_freem(txs->txs_mbuf);
1356 			txs->txs_mbuf = NULL;
1357 		}
1358 
1359 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
1360 
1361 		ifp->if_opackets++;
1362 	}
1363 
1364 	DPRINTF(sc, ("gem_tint: GEM_TX_STATE_MACHINE %x "
1365 		"GEM_TX_DATA_PTR %llx "
1366 		"GEM_TX_COMPLETION %x\n",
1367 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_TX_STATE_MACHINE),
1368 		((long long) bus_space_read_4(sc->sc_bustag, sc->sc_h,
1369 			GEM_TX_DATA_PTR_HI) << 32) |
1370 			     bus_space_read_4(sc->sc_bustag, sc->sc_h,
1371 			GEM_TX_DATA_PTR_LO),
1372 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_TX_COMPLETION)));
1373 	CTR3(KTR_GEM, "gem_tint: GEM_TX_STATE_MACHINE %x "
1374 		"GEM_TX_DATA_PTR %llx "
1375 		"GEM_TX_COMPLETION %x",
1376 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_TX_STATE_MACHINE),
1377 		((long long) bus_space_read_4(sc->sc_bustag, sc->sc_h,
1378 			GEM_TX_DATA_PTR_HI) << 32) |
1379 			     bus_space_read_4(sc->sc_bustag, sc->sc_h,
1380 			GEM_TX_DATA_PTR_LO),
1381 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_TX_COMPLETION));
1382 
1383 	if (STAILQ_FIRST(&sc->sc_txdirtyq) == NULL)
1384 		ifp->if_timer = 0;
1385 
1386 
1387 	DPRINTF(sc, ("%s: gem_tint: watchdog %d\n",
1388 		device_get_name(sc->sc_dev), ifp->if_timer));
1389 	CTR2(KTR_GEM, "%s: gem_tint: watchdog %d",
1390 		device_get_name(sc->sc_dev), ifp->if_timer);
1391 
1392 	/* Freed some descriptors, so reset IFF_OACTIVE and restart. */
1393 	ifp->if_flags &= ~IFF_OACTIVE;
1394 	gem_start(ifp);
1395 }
1396 
1397 static void
1398 gem_rint_timeout(arg)
1399 	void *arg;
1400 {
1401 
1402 	gem_rint((struct gem_softc *)arg);
1403 }
1404 
1405 /*
1406  * Receive interrupt.
1407  */
1408 static void
1409 gem_rint(sc)
1410 	struct gem_softc *sc;
1411 {
1412 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1413 	bus_space_tag_t t = sc->sc_bustag;
1414 	bus_space_handle_t h = sc->sc_h;
1415 	struct ether_header *eh;
1416 	struct gem_rxsoft *rxs;
1417 	struct mbuf *m;
1418 	u_int64_t rxstat;
1419 	int i, len;
1420 
1421 	callout_stop(&sc->sc_rx_ch);
1422 	DPRINTF(sc, ("%s: gem_rint\n", device_get_name(sc->sc_dev)));
1423 	CTR1(KTR_GEM, "%s: gem_rint", device_get_name(sc->sc_dev));
1424 	/*
1425 	 * XXXX Read the lastrx only once at the top for speed.
1426 	 */
1427 	DPRINTF(sc, ("gem_rint: sc->rxptr %d, complete %d\n",
1428 		sc->sc_rxptr, bus_space_read_4(t, h, GEM_RX_COMPLETION)));
1429 	CTR2(KTR_GEM, "gem_rint: sc->rxptr %d, complete %d",
1430 	    sc->sc_rxptr, bus_space_read_4(t, h, GEM_RX_COMPLETION));
1431 	for (i = sc->sc_rxptr; i != bus_space_read_4(t, h, GEM_RX_COMPLETION);
1432 	     i = GEM_NEXTRX(i)) {
1433 		rxs = &sc->sc_rxsoft[i];
1434 
1435 		GEM_CDRXSYNC(sc, i,
1436 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1437 
1438 		rxstat = GEM_DMA_READ(sc, sc->sc_rxdescs[i].gd_flags);
1439 
1440 		if (rxstat & GEM_RD_OWN) {
1441 			/*
1442 			 * The descriptor is still marked as owned, although
1443 			 * it is supposed to have completed. This has been
1444 			 * observed on some machines. Just exiting here
1445 			 * might leave the packet sitting around until another
1446 			 * one arrives to trigger a new interrupt, which is
1447 			 * generally undesirable, so set up a timeout.
1448 			 */
1449 			callout_reset(&sc->sc_rx_ch, GEM_RXOWN_TICKS,
1450 			    gem_rint_timeout, sc);
1451 			break;
1452 		}
1453 
1454 		if (rxstat & GEM_RD_BAD_CRC) {
1455 			device_printf(sc->sc_dev, "receive error: CRC error\n");
1456 			GEM_INIT_RXDESC(sc, i);
1457 			continue;
1458 		}
1459 
1460 		bus_dmamap_sync(sc->sc_dmatag, rxs->rxs_dmamap,
1461 		    BUS_DMASYNC_POSTREAD);
1462 #ifdef GEM_DEBUG
1463 		if (ifp->if_flags & IFF_DEBUG) {
1464 			printf("    rxsoft %p descriptor %d: ", rxs, i);
1465 			printf("gd_flags: 0x%016llx\t", (long long)
1466 				GEM_DMA_READ(sc, sc->sc_rxdescs[i].gd_flags));
1467 			printf("gd_addr: 0x%016llx\n", (long long)
1468 				GEM_DMA_READ(sc, sc->sc_rxdescs[i].gd_addr));
1469 		}
1470 #endif
1471 
1472 		/*
1473 		 * No errors; receive the packet.  Note the Gem
1474 		 * includes the CRC with every packet.
1475 		 */
1476 		len = GEM_RD_BUFLEN(rxstat);
1477 
1478 		/*
1479 		 * Allocate a new mbuf cluster.  If that fails, we are
1480 		 * out of memory, and must drop the packet and recycle
1481 		 * the buffer that's already attached to this descriptor.
1482 		 */
1483 		m = rxs->rxs_mbuf;
1484 		if (gem_add_rxbuf(sc, i) != 0) {
1485 			ifp->if_ierrors++;
1486 			GEM_INIT_RXDESC(sc, i);
1487 			bus_dmamap_sync(sc->sc_dmatag, rxs->rxs_dmamap,
1488 			    BUS_DMASYNC_PREREAD);
1489 			continue;
1490 		}
1491 		m->m_data += 2; /* We're already off by two */
1492 
1493 		ifp->if_ipackets++;
1494 		eh = mtod(m, struct ether_header *);
1495 		m->m_pkthdr.rcvif = ifp;
1496 		m->m_pkthdr.len = m->m_len = len - ETHER_CRC_LEN;
1497 		m_adj(m, sizeof(struct ether_header));
1498 
1499 		/* Pass it on. */
1500 		ether_input(ifp, eh, m);
1501 	}
1502 
1503 	/* Update the receive pointer. */
1504 	sc->sc_rxptr = i;
1505 	bus_space_write_4(t, h, GEM_RX_KICK, i);
1506 
1507 	DPRINTF(sc, ("gem_rint: done sc->rxptr %d, complete %d\n",
1508 		sc->sc_rxptr, bus_space_read_4(t, h, GEM_RX_COMPLETION)));
1509 	CTR2(KTR_GEM, "gem_rint: done sc->rxptr %d, complete %d",
1510 		sc->sc_rxptr, bus_space_read_4(t, h, GEM_RX_COMPLETION));
1511 
1512 }
1513 
1514 
1515 /*
1516  * gem_add_rxbuf:
1517  *
1518  *	Add a receive buffer to the indicated descriptor.
1519  */
1520 static int
1521 gem_add_rxbuf(sc, idx)
1522 	struct gem_softc *sc;
1523 	int idx;
1524 {
1525 	struct gem_rxsoft *rxs = &sc->sc_rxsoft[idx];
1526 	struct mbuf *m;
1527 	int error;
1528 
1529 	MGETHDR(m, M_DONTWAIT, MT_DATA);
1530 	if (m == NULL)
1531 		return (ENOBUFS);
1532 
1533 	MCLGET(m, M_DONTWAIT);
1534 	if ((m->m_flags & M_EXT) == 0) {
1535 		m_freem(m);
1536 		return (ENOBUFS);
1537 	}
1538 
1539 #ifdef GEM_DEBUG
1540 	/* bzero the packet to check dma */
1541 	memset(m->m_ext.ext_buf, 0, m->m_ext.ext_size);
1542 #endif
1543 
1544 	if (rxs->rxs_mbuf != NULL)
1545 		bus_dmamap_unload(sc->sc_dmatag, rxs->rxs_dmamap);
1546 
1547 	rxs->rxs_mbuf = m;
1548 
1549 	error = bus_dmamap_load(sc->sc_dmatag, rxs->rxs_dmamap,
1550 	    m->m_ext.ext_buf, m->m_ext.ext_size, gem_rxdma_callback, rxs,
1551 	    BUS_DMA_NOWAIT);
1552 	if (error != 0 || rxs->rxs_paddr == 0) {
1553 		device_printf(sc->sc_dev, "can't load rx DMA map %d, error = "
1554 		    "%d\n", idx, error);
1555 		panic("gem_add_rxbuf");	/* XXX */
1556 	}
1557 
1558 	bus_dmamap_sync(sc->sc_dmatag, rxs->rxs_dmamap, BUS_DMASYNC_PREREAD);
1559 
1560 	GEM_INIT_RXDESC(sc, idx);
1561 
1562 	return (0);
1563 }
1564 
1565 
1566 static void
1567 gem_eint(sc, status)
1568 	struct gem_softc *sc;
1569 	u_int status;
1570 {
1571 
1572 	if ((status & GEM_INTR_MIF) != 0) {
1573 		device_printf(sc->sc_dev, "XXXlink status changed\n");
1574 		return;
1575 	}
1576 
1577 	device_printf(sc->sc_dev, "status=%x\n", status);
1578 }
1579 
1580 
1581 void
1582 gem_intr(v)
1583 	void *v;
1584 {
1585 	struct gem_softc *sc = (struct gem_softc *)v;
1586 	bus_space_tag_t t = sc->sc_bustag;
1587 	bus_space_handle_t seb = sc->sc_h;
1588 	u_int32_t status;
1589 
1590 	status = bus_space_read_4(t, seb, GEM_STATUS);
1591 	DPRINTF(sc, ("%s: gem_intr: cplt %x, status %x\n",
1592 		device_get_name(sc->sc_dev), (status>>19),
1593 		(u_int)status));
1594 	CTR3(KTR_GEM, "%s: gem_intr: cplt %x, status %x",
1595 		device_get_name(sc->sc_dev), (status>>19),
1596 		(u_int)status);
1597 
1598 	if ((status & (GEM_INTR_RX_TAG_ERR | GEM_INTR_BERR)) != 0)
1599 		gem_eint(sc, status);
1600 
1601 	if ((status & (GEM_INTR_TX_EMPTY | GEM_INTR_TX_INTME)) != 0)
1602 		gem_tint(sc);
1603 
1604 	if ((status & (GEM_INTR_RX_DONE | GEM_INTR_RX_NOBUF)) != 0)
1605 		gem_rint(sc);
1606 
1607 	/* We should eventually do more than just print out error stats. */
1608 	if (status & GEM_INTR_TX_MAC) {
1609 		int txstat = bus_space_read_4(t, seb, GEM_MAC_TX_STATUS);
1610 		if (txstat & ~GEM_MAC_TX_XMIT_DONE)
1611 			printf("MAC tx fault, status %x\n", txstat);
1612 	}
1613 	if (status & GEM_INTR_RX_MAC) {
1614 		int rxstat = bus_space_read_4(t, seb, GEM_MAC_RX_STATUS);
1615 		if (rxstat & ~(GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT))
1616 			printf("MAC rx fault, status %x\n", rxstat);
1617 	}
1618 }
1619 
1620 
1621 static void
1622 gem_watchdog(ifp)
1623 	struct ifnet *ifp;
1624 {
1625 	struct gem_softc *sc = ifp->if_softc;
1626 
1627 	DPRINTF(sc, ("gem_watchdog: GEM_RX_CONFIG %x GEM_MAC_RX_STATUS %x "
1628 		"GEM_MAC_RX_CONFIG %x\n",
1629 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_RX_CONFIG),
1630 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_MAC_RX_STATUS),
1631 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_MAC_RX_CONFIG)));
1632 	CTR3(KTR_GEM, "gem_watchdog: GEM_RX_CONFIG %x GEM_MAC_RX_STATUS %x "
1633 		"GEM_MAC_RX_CONFIG %x",
1634 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_RX_CONFIG),
1635 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_MAC_RX_STATUS),
1636 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_MAC_RX_CONFIG));
1637 	CTR3(KTR_GEM, "gem_watchdog: GEM_TX_CONFIG %x GEM_MAC_TX_STATUS %x "
1638 		"GEM_MAC_TX_CONFIG %x",
1639 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_TX_CONFIG),
1640 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_MAC_TX_STATUS),
1641 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_MAC_TX_CONFIG));
1642 
1643 	device_printf(sc->sc_dev, "device timeout\n");
1644 	++ifp->if_oerrors;
1645 
1646 	/* Try to get more packets going. */
1647 	gem_start(ifp);
1648 }
1649 
1650 /*
1651  * Initialize the MII Management Interface
1652  */
1653 static void
1654 gem_mifinit(sc)
1655 	struct gem_softc *sc;
1656 {
1657 	bus_space_tag_t t = sc->sc_bustag;
1658 	bus_space_handle_t mif = sc->sc_h;
1659 
1660 	/* Configure the MIF in frame mode */
1661 	sc->sc_mif_config = bus_space_read_4(t, mif, GEM_MIF_CONFIG);
1662 	sc->sc_mif_config &= ~GEM_MIF_CONFIG_BB_ENA;
1663 	bus_space_write_4(t, mif, GEM_MIF_CONFIG, sc->sc_mif_config);
1664 }
1665 
1666 /*
1667  * MII interface
1668  *
1669  * The GEM MII interface supports at least three different operating modes:
1670  *
1671  * Bitbang mode is implemented using data, clock and output enable registers.
1672  *
1673  * Frame mode is implemented by loading a complete frame into the frame
1674  * register and polling the valid bit for completion.
1675  *
1676  * Polling mode uses the frame register but completion is indicated by
1677  * an interrupt.
1678  *
1679  */
1680 int
1681 gem_mii_readreg(dev, phy, reg)
1682 	device_t dev;
1683 	int phy, reg;
1684 {
1685 	struct gem_softc *sc = device_get_softc(dev);
1686 	bus_space_tag_t t = sc->sc_bustag;
1687 	bus_space_handle_t mif = sc->sc_h;
1688 	int n;
1689 	u_int32_t v;
1690 
1691 #ifdef GEM_DEBUG_PHY
1692 	printf("gem_mii_readreg: phy %d reg %d\n", phy, reg);
1693 #endif
1694 
1695 #if 0
1696 	/* Select the desired PHY in the MIF configuration register */
1697 	v = bus_space_read_4(t, mif, GEM_MIF_CONFIG);
1698 	/* Clear PHY select bit */
1699 	v &= ~GEM_MIF_CONFIG_PHY_SEL;
1700 	if (phy == GEM_PHYAD_EXTERNAL)
1701 		/* Set PHY select bit to get at external device */
1702 		v |= GEM_MIF_CONFIG_PHY_SEL;
1703 	bus_space_write_4(t, mif, GEM_MIF_CONFIG, v);
1704 #endif
1705 
1706 	/* Construct the frame command */
1707 	v = (reg << GEM_MIF_REG_SHIFT)	| (phy << GEM_MIF_PHY_SHIFT) |
1708 		GEM_MIF_FRAME_READ;
1709 
1710 	bus_space_write_4(t, mif, GEM_MIF_FRAME, v);
1711 	for (n = 0; n < 100; n++) {
1712 		DELAY(1);
1713 		v = bus_space_read_4(t, mif, GEM_MIF_FRAME);
1714 		if (v & GEM_MIF_FRAME_TA0)
1715 			return (v & GEM_MIF_FRAME_DATA);
1716 	}
1717 
1718 	device_printf(sc->sc_dev, "mii_read timeout\n");
1719 	return (0);
1720 }
1721 
1722 int
1723 gem_mii_writereg(dev, phy, reg, val)
1724 	device_t dev;
1725 	int phy, reg, val;
1726 {
1727 	struct gem_softc *sc = device_get_softc(dev);
1728 	bus_space_tag_t t = sc->sc_bustag;
1729 	bus_space_handle_t mif = sc->sc_h;
1730 	int n;
1731 	u_int32_t v;
1732 
1733 #ifdef GEM_DEBUG_PHY
1734 	printf("gem_mii_writereg: phy %d reg %d val %x\n", phy, reg, val);
1735 #endif
1736 
1737 #if 0
1738 	/* Select the desired PHY in the MIF configuration register */
1739 	v = bus_space_read_4(t, mif, GEM_MIF_CONFIG);
1740 	/* Clear PHY select bit */
1741 	v &= ~GEM_MIF_CONFIG_PHY_SEL;
1742 	if (phy == GEM_PHYAD_EXTERNAL)
1743 		/* Set PHY select bit to get at external device */
1744 		v |= GEM_MIF_CONFIG_PHY_SEL;
1745 	bus_space_write_4(t, mif, GEM_MIF_CONFIG, v);
1746 #endif
1747 	/* Construct the frame command */
1748 	v = GEM_MIF_FRAME_WRITE			|
1749 	    (phy << GEM_MIF_PHY_SHIFT)		|
1750 	    (reg << GEM_MIF_REG_SHIFT)		|
1751 	    (val & GEM_MIF_FRAME_DATA);
1752 
1753 	bus_space_write_4(t, mif, GEM_MIF_FRAME, v);
1754 	for (n = 0; n < 100; n++) {
1755 		DELAY(1);
1756 		v = bus_space_read_4(t, mif, GEM_MIF_FRAME);
1757 		if (v & GEM_MIF_FRAME_TA0)
1758 			return (1);
1759 	}
1760 
1761 	device_printf(sc->sc_dev, "mii_write timeout\n");
1762 	return (0);
1763 }
1764 
1765 void
1766 gem_mii_statchg(dev)
1767 	device_t dev;
1768 {
1769 	struct gem_softc *sc = device_get_softc(dev);
1770 #ifdef GEM_DEBUG
1771 	int instance = IFM_INST(sc->sc_mii->mii_media.ifm_cur->ifm_media);
1772 #endif
1773 	bus_space_tag_t t = sc->sc_bustag;
1774 	bus_space_handle_t mac = sc->sc_h;
1775 	u_int32_t v;
1776 
1777 #ifdef GEM_DEBUG
1778 	if (sc->sc_debug)
1779 		printf("gem_mii_statchg: status change: phy = %d\n",
1780 			sc->sc_phys[instance]);
1781 #endif
1782 
1783 	/* Set tx full duplex options */
1784 	bus_space_write_4(t, mac, GEM_MAC_TX_CONFIG, 0);
1785 	DELAY(10000); /* reg must be cleared and delay before changing. */
1786 	v = GEM_MAC_TX_ENA_IPG0|GEM_MAC_TX_NGU|GEM_MAC_TX_NGU_LIMIT|
1787 		GEM_MAC_TX_ENABLE;
1788 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) != 0) {
1789 		v |= GEM_MAC_TX_IGN_CARRIER|GEM_MAC_TX_IGN_COLLIS;
1790 	}
1791 	bus_space_write_4(t, mac, GEM_MAC_TX_CONFIG, v);
1792 
1793 	/* XIF Configuration */
1794  /* We should really calculate all this rather than rely on defaults */
1795 	v = bus_space_read_4(t, mac, GEM_MAC_XIF_CONFIG);
1796 	v = GEM_MAC_XIF_LINK_LED;
1797 	v |= GEM_MAC_XIF_TX_MII_ENA;
1798 	/* If an external transceiver is connected, enable its MII drivers */
1799 	sc->sc_mif_config = bus_space_read_4(t, mac, GEM_MIF_CONFIG);
1800 	if ((sc->sc_mif_config & GEM_MIF_CONFIG_MDI1) != 0) {
1801 		/* External MII needs echo disable if half duplex. */
1802 		if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) != 0)
1803 			/* turn on full duplex LED */
1804 			v |= GEM_MAC_XIF_FDPLX_LED;
1805  			else
1806 	 			/* half duplex -- disable echo */
1807 		 		v |= GEM_MAC_XIF_ECHO_DISABL;
1808 	} else {
1809 		/* Internal MII needs buf enable */
1810 		v |= GEM_MAC_XIF_MII_BUF_ENA;
1811 	}
1812 	bus_space_write_4(t, mac, GEM_MAC_XIF_CONFIG, v);
1813 }
1814 
1815 int
1816 gem_mediachange(ifp)
1817 	struct ifnet *ifp;
1818 {
1819 	struct gem_softc *sc = ifp->if_softc;
1820 
1821 	/* XXX Add support for serial media. */
1822 
1823 	return (mii_mediachg(sc->sc_mii));
1824 }
1825 
1826 void
1827 gem_mediastatus(ifp, ifmr)
1828 	struct ifnet *ifp;
1829 	struct ifmediareq *ifmr;
1830 {
1831 	struct gem_softc *sc = ifp->if_softc;
1832 
1833 	if ((ifp->if_flags & IFF_UP) == 0)
1834 		return;
1835 
1836 	mii_pollstat(sc->sc_mii);
1837 	ifmr->ifm_active = sc->sc_mii->mii_media_active;
1838 	ifmr->ifm_status = sc->sc_mii->mii_media_status;
1839 }
1840 
1841 /*
1842  * Process an ioctl request.
1843  */
1844 static int
1845 gem_ioctl(ifp, cmd, data)
1846 	struct ifnet *ifp;
1847 	u_long cmd;
1848 	caddr_t data;
1849 {
1850 	struct gem_softc *sc = ifp->if_softc;
1851 	struct ifreq *ifr = (struct ifreq *)data;
1852 	int s, error = 0;
1853 
1854 	switch (cmd) {
1855 	case SIOCSIFADDR:
1856 	case SIOCGIFADDR:
1857 	case SIOCSIFMTU:
1858 		error = ether_ioctl(ifp, cmd, data);
1859 		break;
1860 	case SIOCSIFFLAGS:
1861 		if (ifp->if_flags & IFF_UP) {
1862 			if ((sc->sc_flags ^ ifp->if_flags) == IFF_PROMISC)
1863 				gem_setladrf(sc);
1864 			else
1865 				gem_init(sc);
1866 		} else {
1867 			if (ifp->if_flags & IFF_RUNNING)
1868 				gem_stop(ifp, 0);
1869 		}
1870 		sc->sc_flags = ifp->if_flags;
1871 		error = 0;
1872 		break;
1873 	case SIOCADDMULTI:
1874 	case SIOCDELMULTI:
1875 		gem_setladrf(sc);
1876 		error = 0;
1877 		break;
1878 	case SIOCGIFMEDIA:
1879 	case SIOCSIFMEDIA:
1880 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii->mii_media, cmd);
1881 		break;
1882 	default:
1883 		error = ENOTTY;
1884 		break;
1885 	}
1886 
1887 	/* Try to get things going again */
1888 	if (ifp->if_flags & IFF_UP)
1889 		gem_start(ifp);
1890 	splx(s);
1891 	return (error);
1892 }
1893 
1894 /*
1895  * Set up the logical address filter.
1896  */
1897 static void
1898 gem_setladrf(sc)
1899 	struct gem_softc *sc;
1900 {
1901 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1902 	struct ifmultiaddr *inm;
1903 	struct sockaddr_dl *sdl;
1904 	bus_space_tag_t t = sc->sc_bustag;
1905 	bus_space_handle_t h = sc->sc_h;
1906 	u_char *cp;
1907 	u_int32_t crc;
1908 	u_int32_t hash[16];
1909 	u_int32_t v;
1910 	int len;
1911 
1912 	/* Clear hash table */
1913 	memset(hash, 0, sizeof(hash));
1914 
1915 	/* Get current RX configuration */
1916 	v = bus_space_read_4(t, h, GEM_MAC_RX_CONFIG);
1917 
1918 	if ((ifp->if_flags & IFF_PROMISC) != 0) {
1919 		/* Turn on promiscuous mode; turn off the hash filter */
1920 		v |= GEM_MAC_RX_PROMISCUOUS;
1921 		v &= ~GEM_MAC_RX_HASH_FILTER;
1922 		;
1923 		goto chipit;
1924 	}
1925 	if ((ifp->if_flags & IFF_ALLMULTI) != 0) {
1926 		hash[3] = hash[2] = hash[1] = hash[0] = 0xffff;
1927 		ifp->if_flags |= IFF_ALLMULTI;
1928 		goto chipit;
1929 	}
1930 
1931 	/* Turn off promiscuous mode; turn on the hash filter */
1932 	v &= ~GEM_MAC_RX_PROMISCUOUS;
1933 	v |= GEM_MAC_RX_HASH_FILTER;
1934 
1935 	/*
1936 	 * Set up multicast address filter by passing all multicast addresses
1937 	 * through a crc generator, and then using the high order 6 bits as an
1938 	 * index into the 256 bit logical address filter.  The high order bit
1939 	 * selects the word, while the rest of the bits select the bit within
1940 	 * the word.
1941 	 */
1942 
1943 	TAILQ_FOREACH(inm, &sc->sc_arpcom.ac_if.if_multiaddrs, ifma_link) {
1944 		if (inm->ifma_addr->sa_family != AF_LINK)
1945 			continue;
1946 		sdl = (struct sockaddr_dl *)inm->ifma_addr;
1947 		cp = LLADDR(sdl);
1948 		crc = 0xffffffff;
1949 		for (len = sdl->sdl_alen; --len >= 0;) {
1950 			int octet = *cp++;
1951 			int i;
1952 
1953 #define MC_POLY_LE	0xedb88320UL	/* mcast crc, little endian */
1954 			for (i = 0; i < 8; i++) {
1955 				if ((crc & 1) ^ (octet & 1)) {
1956 					crc >>= 1;
1957 					crc ^= MC_POLY_LE;
1958 				} else {
1959 					crc >>= 1;
1960 				}
1961 				octet >>= 1;
1962 			}
1963 		}
1964 		/* Just want the 8 most significant bits. */
1965 		crc >>= 24;
1966 
1967 		/* Set the corresponding bit in the filter. */
1968 		hash[crc >> 4] |= 1 << (crc & 0xf);
1969 	}
1970 
1971 chipit:
1972 	/* Now load the hash table into the chip */
1973 	bus_space_write_4(t, h, GEM_MAC_HASH0, hash[0]);
1974 	bus_space_write_4(t, h, GEM_MAC_HASH1, hash[1]);
1975 	bus_space_write_4(t, h, GEM_MAC_HASH2, hash[2]);
1976 	bus_space_write_4(t, h, GEM_MAC_HASH3, hash[3]);
1977 	bus_space_write_4(t, h, GEM_MAC_HASH4, hash[4]);
1978 	bus_space_write_4(t, h, GEM_MAC_HASH5, hash[5]);
1979 	bus_space_write_4(t, h, GEM_MAC_HASH6, hash[6]);
1980 	bus_space_write_4(t, h, GEM_MAC_HASH7, hash[7]);
1981 	bus_space_write_4(t, h, GEM_MAC_HASH8, hash[8]);
1982 	bus_space_write_4(t, h, GEM_MAC_HASH9, hash[9]);
1983 	bus_space_write_4(t, h, GEM_MAC_HASH10, hash[10]);
1984 	bus_space_write_4(t, h, GEM_MAC_HASH11, hash[11]);
1985 	bus_space_write_4(t, h, GEM_MAC_HASH12, hash[12]);
1986 	bus_space_write_4(t, h, GEM_MAC_HASH13, hash[13]);
1987 	bus_space_write_4(t, h, GEM_MAC_HASH14, hash[14]);
1988 	bus_space_write_4(t, h, GEM_MAC_HASH15, hash[15]);
1989 
1990 	bus_space_write_4(t, h, GEM_MAC_RX_CONFIG, v);
1991 }
1992 
1993 #if notyet
1994 
1995 /*
1996  * gem_power:
1997  *
1998  *	Power management (suspend/resume) hook.
1999  */
2000 void
2001 static gem_power(why, arg)
2002 	int why;
2003 	void *arg;
2004 {
2005 	struct gem_softc *sc = arg;
2006 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
2007 	int s;
2008 
2009 	s = splnet();
2010 	switch (why) {
2011 	case PWR_SUSPEND:
2012 	case PWR_STANDBY:
2013 		gem_stop(ifp, 1);
2014 		if (sc->sc_power != NULL)
2015 			(*sc->sc_power)(sc, why);
2016 		break;
2017 	case PWR_RESUME:
2018 		if (ifp->if_flags & IFF_UP) {
2019 			if (sc->sc_power != NULL)
2020 				(*sc->sc_power)(sc, why);
2021 			gem_init(ifp);
2022 		}
2023 		break;
2024 	case PWR_SOFTSUSPEND:
2025 	case PWR_SOFTSTANDBY:
2026 	case PWR_SOFTRESUME:
2027 		break;
2028 	}
2029 	splx(s);
2030 }
2031 #endif
2032