xref: /freebsd/sys/dev/gem/if_gem.c (revision c17d43407fe04133a94055b0dbc7ea8965654a9f)
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_tint(struct gem_softc *);
94 #ifdef notyet
95 static void	gem_power(int, void *);
96 #endif
97 
98 devclass_t gem_devclass;
99 DRIVER_MODULE(miibus, gem, miibus_driver, miibus_devclass, 0, 0);
100 MODULE_DEPEND(gem, miibus, 1, 1, 1);
101 
102 #ifdef GEM_DEBUG
103 #define	DPRINTF(sc, x)	if ((sc)->sc_arpcom.ac_if.if_flags & IFF_DEBUG) \
104 				printf x
105 #include <sys/ktr.h>
106 #define	KTR_GEM		KTR_CT2
107 #else
108 #define	DPRINTF(sc, x)	/* nothing */
109 #endif
110 
111 #define	GEM_NSEGS GEM_NTXSEGS
112 
113 /*
114  * gem_attach:
115  *
116  *	Attach a Gem interface to the system.
117  */
118 int
119 gem_attach(sc)
120 	struct gem_softc *sc;
121 {
122 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
123 	struct mii_softc *child;
124 	int i, error;
125 
126 	/* Make sure the chip is stopped. */
127 	ifp->if_softc = sc;
128 	gem_reset(sc);
129 
130 	error = bus_dma_tag_create(NULL, 1, 0, BUS_SPACE_MAXADDR_32BIT,
131 	    BUS_SPACE_MAXADDR, NULL, NULL, MCLBYTES, GEM_NSEGS,
132 	    BUS_SPACE_MAXSIZE_32BIT, 0, &sc->sc_pdmatag);
133 	if (error)
134 		return (error);
135 
136 	error = bus_dma_tag_create(sc->sc_pdmatag, 1, 0,
137 	    BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL, MAXBSIZE,
138 	    GEM_NSEGS, BUS_SPACE_MAXSIZE_32BIT, BUS_DMA_ALLOCNOW,
139 	    &sc->sc_dmatag);
140 	if (error)
141 		goto fail_0;
142 
143 	error = bus_dma_tag_create(sc->sc_pdmatag, PAGE_SIZE, 0,
144 	    BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL,
145 	    sizeof(struct gem_control_data), 1,
146 	    sizeof(struct gem_control_data), BUS_DMA_ALLOCNOW,
147 	    &sc->sc_cdmatag);
148 	if (error)
149 		goto fail_1;
150 
151 	/*
152 	 * Allocate the control data structures, and create and load the
153 	 * DMA map for it.
154 	 */
155 	if ((error = bus_dmamem_alloc(sc->sc_cdmatag,
156 	    (void **)&sc->sc_control_data, 0, &sc->sc_cddmamap))) {
157 		device_printf(sc->sc_dev, "unable to allocate control data,"
158 		    " error = %d\n", error);
159 		goto fail_2;
160 	}
161 
162 	sc->sc_cddma = 0;
163 	if ((error = bus_dmamap_load(sc->sc_cdmatag, sc->sc_cddmamap,
164 	    sc->sc_control_data, sizeof(struct gem_control_data),
165 	    gem_cddma_callback, sc, 0)) != 0 || sc->sc_cddma == 0) {
166 		device_printf(sc->sc_dev, "unable to load control data DMA "
167 		    "map, error = %d\n", error);
168 		goto fail_3;
169 	}
170 
171 	/*
172 	 * Initialize the transmit job descriptors.
173 	 */
174 	STAILQ_INIT(&sc->sc_txfreeq);
175 	STAILQ_INIT(&sc->sc_txdirtyq);
176 
177 	/*
178 	 * Create the transmit buffer DMA maps.
179 	 */
180 	error = ENOMEM;
181 	for (i = 0; i < GEM_TXQUEUELEN; i++) {
182 		struct gem_txsoft *txs;
183 
184 		txs = &sc->sc_txsoft[i];
185 		txs->txs_mbuf = NULL;
186 		txs->txs_ndescs = 0;
187 		if ((error = bus_dmamap_create(sc->sc_dmatag, 0,
188 		    &txs->txs_dmamap)) != 0) {
189 			device_printf(sc->sc_dev, "unable to create tx DMA map "
190 			    "%d, error = %d\n", i, error);
191 			goto fail_4;
192 		}
193 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
194 	}
195 
196 	/*
197 	 * Create the receive buffer DMA maps.
198 	 */
199 	for (i = 0; i < GEM_NRXDESC; i++) {
200 		if ((error = bus_dmamap_create(sc->sc_dmatag, 0,
201 		    &sc->sc_rxsoft[i].rxs_dmamap)) != 0) {
202 			device_printf(sc->sc_dev, "unable to create rx DMA map "
203 			    "%d, error = %d\n", i, error);
204 			goto fail_5;
205 		}
206 		sc->sc_rxsoft[i].rxs_mbuf = NULL;
207 	}
208 
209 
210 	gem_mifinit(sc);
211 
212 	if ((error = mii_phy_probe(sc->sc_dev, &sc->sc_miibus, gem_mediachange,
213 	    gem_mediastatus)) != 0) {
214 		device_printf(sc->sc_dev, "phy probe failed: %d\n", error);
215 		goto fail_5;
216 	}
217 	sc->sc_mii = device_get_softc(sc->sc_miibus);
218 
219 	/*
220 	 * From this point forward, the attachment cannot fail.  A failure
221 	 * before this point releases all resources that may have been
222 	 * allocated.
223 	 */
224 
225 	/* Announce ourselves. */
226 	device_printf(sc->sc_dev, "Ethernet address:");
227 	for (i = 0; i < 6; i++)
228 		printf("%c%02x", i > 0 ? ':' : ' ', sc->sc_arpcom.ac_enaddr[i]);
229 	printf("\n");
230 
231 	/* Initialize ifnet structure. */
232 	ifp->if_softc = sc;
233 	ifp->if_unit = device_get_unit(sc->sc_dev);
234 	ifp->if_name = "gem";
235 	ifp->if_mtu = ETHERMTU;
236 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
237 	ifp->if_start = gem_start;
238 	ifp->if_ioctl = gem_ioctl;
239 	ifp->if_watchdog = gem_watchdog;
240 	ifp->if_init = gem_init;
241 	ifp->if_output = ether_output;
242 	ifp->if_snd.ifq_maxlen = GEM_TXQUEUELEN;
243 	/*
244 	 * Walk along the list of attached MII devices and
245 	 * establish an `MII instance' to `phy number'
246 	 * mapping. We'll use this mapping in media change
247 	 * requests to determine which phy to use to program
248 	 * the MIF configuration register.
249 	 */
250 	for (child = LIST_FIRST(&sc->sc_mii->mii_phys); child != NULL;
251 	     child = LIST_NEXT(child, mii_list)) {
252 		/*
253 		 * Note: we support just two PHYs: the built-in
254 		 * internal device and an external on the MII
255 		 * connector.
256 		 */
257 		if (child->mii_phy > 1 || child->mii_inst > 1) {
258 			device_printf(sc->sc_dev, "cannot accomodate "
259 			    "MII device %s at phy %d, instance %d\n",
260 			    device_get_name(child->mii_dev),
261 			    child->mii_phy, child->mii_inst);
262 			continue;
263 		}
264 
265 		sc->sc_phys[child->mii_inst] = child->mii_phy;
266 	}
267 
268 	/*
269 	 * Now select and activate the PHY we will use.
270 	 *
271 	 * The order of preference is External (MDI1),
272 	 * Internal (MDI0), Serial Link (no MII).
273 	 */
274 	if (sc->sc_phys[1]) {
275 #ifdef GEM_DEBUG
276 		printf("using external phy\n");
277 #endif
278 		sc->sc_mif_config |= GEM_MIF_CONFIG_PHY_SEL;
279 	} else {
280 #ifdef GEM_DEBUG
281 		printf("using internal phy\n");
282 #endif
283 		sc->sc_mif_config &= ~GEM_MIF_CONFIG_PHY_SEL;
284 	}
285 	bus_space_write_4(sc->sc_bustag, sc->sc_h, GEM_MIF_CONFIG,
286 	    sc->sc_mif_config);
287 	/* Attach the interface. */
288 	ether_ifattach(ifp, ETHER_BPF_SUPPORTED);
289 
290 #if notyet
291 	/*
292 	 * Add a suspend hook to make sure we come back up after a
293 	 * resume.
294 	 */
295 	sc->sc_powerhook = powerhook_establish(gem_power, sc);
296 	if (sc->sc_powerhook == NULL)
297 		device_printf(sc->sc_dev, "WARNING: unable to establish power "
298 		    "hook\n");
299 #endif
300 
301 	callout_init(&sc->sc_tick_ch, 0);
302 	return (0);
303 
304 	/*
305 	 * Free any resources we've allocated during the failed attach
306 	 * attempt.  Do this in reverse order and fall through.
307 	 */
308 fail_5:
309 	for (i = 0; i < GEM_NRXDESC; i++) {
310 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
311 			bus_dmamap_destroy(sc->sc_dmatag,
312 			    sc->sc_rxsoft[i].rxs_dmamap);
313 	}
314 fail_4:
315 	for (i = 0; i < GEM_TXQUEUELEN; i++) {
316 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
317 			bus_dmamap_destroy(sc->sc_dmatag,
318 			    sc->sc_txsoft[i].txs_dmamap);
319 	}
320 	bus_dmamap_unload(sc->sc_dmatag, sc->sc_cddmamap);
321 fail_3:
322 	bus_dmamem_free(sc->sc_cdmatag, sc->sc_control_data,
323 	    sc->sc_cddmamap);
324 fail_2:
325 	bus_dma_tag_destroy(sc->sc_cdmatag);
326 fail_1:
327 	bus_dma_tag_destroy(sc->sc_dmatag);
328 fail_0:
329 	bus_dma_tag_destroy(sc->sc_pdmatag);
330 	return (error);
331 }
332 
333 static void
334 gem_cddma_callback(xsc, segs, nsegs, error)
335 	void *xsc;
336 	bus_dma_segment_t *segs;
337 	int nsegs;
338 	int error;
339 {
340 	struct gem_softc *sc = (struct gem_softc *)xsc;
341 
342 	if (error != 0)
343 		return;
344 	if (nsegs != 1) {
345 		/* can't happen... */
346 		panic("gem_cddma_callback: bad control buffer segment count");
347 	}
348 	sc->sc_cddma = segs[0].ds_addr;
349 }
350 
351 static void
352 gem_rxdma_callback(xsc, segs, nsegs, error)
353 	void *xsc;
354 	bus_dma_segment_t *segs;
355 	int nsegs;
356 	int error;
357 {
358 	struct gem_rxsoft *rxs = (struct gem_rxsoft *)xsc;
359 
360 	if (error != 0)
361 		return;
362 	if (nsegs != 1) {
363 		/* can't happen... */
364 		panic("gem_rxdma_callback: bad control buffer segment count");
365 	}
366 	rxs->rxs_paddr = segs[0].ds_addr;
367 }
368 
369 /*
370  * This is called multiple times in our version of dmamap_load_mbuf, but should
371  * be fit for a generic version that only calls it once.
372  */
373 static void
374 gem_txdma_callback(xsc, segs, nsegs, error)
375 	void *xsc;
376 	bus_dma_segment_t *segs;
377 	int nsegs;
378 	int error;
379 {
380 	struct gem_txdma *tx = (struct gem_txdma *)xsc;
381 	int seg;
382 
383 	tx->txd_error = error;
384 	if (error != 0)
385 		return;
386 	tx->txd_nsegs = nsegs;
387 
388 	/*
389 	 * Initialize the transmit descriptors.
390 	 */
391 	for (seg = 0; seg < nsegs;
392 	     seg++, tx->txd_nexttx = GEM_NEXTTX(tx->txd_nexttx)) {
393 		uint64_t flags;
394 
395 		DPRINTF(tx->txd_sc, ("txdma_cb: mapping seg %d (txd %d), len "
396 		    "%lx, addr %#lx (%#lx)\n",  seg, tx->txd_nexttx,
397 		    segs[seg].ds_len, segs[seg].ds_addr,
398 		    GEM_DMA_WRITE(tx->txd_sc, segs[seg].ds_addr)));
399 		CTR5(KTR_GEM, "txdma_cb: mapping seg %d (txd %d), len "
400 		    "%lx, addr %#lx (%#lx)",  seg, tx->txd_nexttx,
401 		    segs[seg].ds_len, segs[seg].ds_addr,
402 		    GEM_DMA_WRITE(tx->txd_sc, segs[seg].ds_addr));
403 		/*
404 		 * If this is the first descriptor we're
405 		 * enqueueing, set the start of packet flag,
406 		 * and the checksum stuff if we want the hardware
407 		 * to do it.
408 		 */
409 		tx->txd_sc->sc_txdescs[tx->txd_nexttx].gd_addr =
410 		    GEM_DMA_WRITE(tx->txd_sc, segs[seg].ds_addr);
411 		flags = segs[seg].ds_len & GEM_TD_BUFSIZE;
412 		if ((tx->txd_flags & GTXD_FIRST) != 0 && seg == 0) {
413 			CTR2(KTR_GEM, "txdma_cb: start of packet at seg %d, "
414 			    "tx %d", seg, tx->txd_nexttx);
415 			flags |= GEM_TD_START_OF_PACKET;
416 		}
417 		if ((tx->txd_flags & GTXD_LAST) != 0 && seg == nsegs - 1) {
418 			CTR2(KTR_GEM, "txdma_cb: end of packet at seg %d, "
419 			    "tx %d", seg, tx->txd_nexttx);
420 			flags |= GEM_TD_END_OF_PACKET;
421 		}
422 		tx->txd_sc->sc_txdescs[tx->txd_nexttx].gd_flags =
423 		    GEM_DMA_WRITE(tx->txd_sc, flags);
424 		tx->txd_lasttx = tx->txd_nexttx;
425 	}
426 }
427 
428 static void
429 gem_tick(arg)
430 	void *arg;
431 {
432 	struct gem_softc *sc = arg;
433 	int s;
434 
435 	s = splnet();
436 	mii_tick(sc->sc_mii);
437 	splx(s);
438 
439 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
440 }
441 
442 static int
443 gem_bitwait(sc, r, clr, set)
444 	struct gem_softc *sc;
445 	bus_addr_t r;
446 	u_int32_t clr;
447 	u_int32_t set;
448 {
449 	int i;
450 	u_int32_t reg;
451 
452 	for (i = TRIES; i--; DELAY(100)) {
453 		reg = bus_space_read_4(sc->sc_bustag, sc->sc_h, r);
454 		if ((r & clr) == 0 && (r & set) == set)
455 			return (1);
456 	}
457 	return (0);
458 }
459 
460 void
461 gem_reset(sc)
462 	struct gem_softc *sc;
463 {
464 	bus_space_tag_t t = sc->sc_bustag;
465 	bus_space_handle_t h = sc->sc_h;
466 	int s;
467 
468 	s = splnet();
469 	DPRINTF(sc, ("%s: gem_reset\n", device_get_name(sc->sc_dev)));
470 	CTR1(KTR_GEM, "%s: gem_reset", device_get_name(sc->sc_dev));
471 	gem_reset_rx(sc);
472 	gem_reset_tx(sc);
473 
474 	/* Do a full reset */
475 	bus_space_write_4(t, h, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX);
476 	if (!gem_bitwait(sc, GEM_RESET, GEM_RESET_RX | GEM_RESET_TX, 0))
477 		device_printf(sc->sc_dev, "cannot reset device\n");
478 	splx(s);
479 }
480 
481 
482 /*
483  * gem_rxdrain:
484  *
485  *	Drain the receive queue.
486  */
487 static void
488 gem_rxdrain(sc)
489 	struct gem_softc *sc;
490 {
491 	struct gem_rxsoft *rxs;
492 	int i;
493 
494 	for (i = 0; i < GEM_NRXDESC; i++) {
495 		rxs = &sc->sc_rxsoft[i];
496 		if (rxs->rxs_mbuf != NULL) {
497 			bus_dmamap_unload(sc->sc_dmatag, rxs->rxs_dmamap);
498 			m_freem(rxs->rxs_mbuf);
499 			rxs->rxs_mbuf = NULL;
500 		}
501 	}
502 }
503 
504 /*
505  * Reset the whole thing.
506  */
507 static void
508 gem_stop(ifp, disable)
509 	struct ifnet *ifp;
510 	int disable;
511 {
512 	struct gem_softc *sc = (struct gem_softc *)ifp->if_softc;
513 	struct gem_txsoft *txs;
514 
515 	DPRINTF(sc, ("%s: gem_stop\n", device_get_name(sc->sc_dev)));
516 	CTR1(KTR_GEM, "%s: gem_stop", device_get_name(sc->sc_dev));
517 
518 	callout_stop(&sc->sc_tick_ch);
519 
520 	/* XXX - Should we reset these instead? */
521 	gem_disable_tx(sc);
522 	gem_disable_rx(sc);
523 
524 	/*
525 	 * Release any queued transmit buffers.
526 	 */
527 	while ((txs = STAILQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
528 		STAILQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
529 		if (txs->txs_ndescs != 0) {
530 			bus_dmamap_unload(sc->sc_dmatag, txs->txs_dmamap);
531 			if (txs->txs_mbuf != NULL) {
532 				m_freem(txs->txs_mbuf);
533 				txs->txs_mbuf = NULL;
534 			}
535 		}
536 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
537 	}
538 
539 	if (disable)
540 		gem_rxdrain(sc);
541 
542 	/*
543 	 * Mark the interface down and cancel the watchdog timer.
544 	 */
545 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
546 	ifp->if_timer = 0;
547 }
548 
549 /*
550  * Reset the receiver
551  */
552 int
553 gem_reset_rx(sc)
554 	struct gem_softc *sc;
555 {
556 	bus_space_tag_t t = sc->sc_bustag;
557 	bus_space_handle_t h = sc->sc_h;
558 
559 	/*
560 	 * Resetting while DMA is in progress can cause a bus hang, so we
561 	 * disable DMA first.
562 	 */
563 	gem_disable_rx(sc);
564 	bus_space_write_4(t, h, GEM_RX_CONFIG, 0);
565 	/* Wait till it finishes */
566 	if (!gem_bitwait(sc, GEM_RX_CONFIG, 1, 0))
567 		device_printf(sc->sc_dev, "cannot disable read dma\n");
568 
569 	/* Wait 5ms extra. */
570 	DELAY(5000);
571 
572 	/* Finally, reset the ERX */
573 	bus_space_write_4(t, h, GEM_RESET, GEM_RESET_RX);
574 	/* Wait till it finishes */
575 	if (!gem_bitwait(sc, GEM_RESET, GEM_RESET_TX, 0)) {
576 		device_printf(sc->sc_dev, "cannot reset receiver\n");
577 		return (1);
578 	}
579 	return (0);
580 }
581 
582 
583 /*
584  * Reset the transmitter
585  */
586 static int
587 gem_reset_tx(sc)
588 	struct gem_softc *sc;
589 {
590 	bus_space_tag_t t = sc->sc_bustag;
591 	bus_space_handle_t h = sc->sc_h;
592 	int i;
593 
594 	/*
595 	 * Resetting while DMA is in progress can cause a bus hang, so we
596 	 * disable DMA first.
597 	 */
598 	gem_disable_tx(sc);
599 	bus_space_write_4(t, h, GEM_TX_CONFIG, 0);
600 	/* Wait till it finishes */
601 	if (!gem_bitwait(sc, GEM_TX_CONFIG, 1, 0))
602 		device_printf(sc->sc_dev, "cannot disable read dma\n");
603 
604 	/* Wait 5ms extra. */
605 	DELAY(5000);
606 
607 	/* Finally, reset the ETX */
608 	bus_space_write_4(t, h, GEM_RESET, GEM_RESET_TX);
609 	/* Wait till it finishes */
610 	for (i = TRIES; i--; DELAY(100))
611 		if ((bus_space_read_4(t, h, GEM_RESET) & GEM_RESET_TX) == 0)
612 			break;
613 	if (!gem_bitwait(sc, GEM_RESET, GEM_RESET_TX, 0)) {
614 		device_printf(sc->sc_dev, "cannot reset receiver\n");
615 		return (1);
616 	}
617 	return (0);
618 }
619 
620 /*
621  * disable receiver.
622  */
623 static int
624 gem_disable_rx(sc)
625 	struct gem_softc *sc;
626 {
627 	bus_space_tag_t t = sc->sc_bustag;
628 	bus_space_handle_t h = sc->sc_h;
629 	u_int32_t cfg;
630 
631 	/* Flip the enable bit */
632 	cfg = bus_space_read_4(t, h, GEM_MAC_RX_CONFIG);
633 	cfg &= ~GEM_MAC_RX_ENABLE;
634 	bus_space_write_4(t, h, GEM_MAC_RX_CONFIG, cfg);
635 
636 	/* Wait for it to finish */
637 	return (gem_bitwait(sc, GEM_MAC_RX_CONFIG, GEM_MAC_RX_ENABLE, 0));
638 }
639 
640 /*
641  * disable transmitter.
642  */
643 static int
644 gem_disable_tx(sc)
645 	struct gem_softc *sc;
646 {
647 	bus_space_tag_t t = sc->sc_bustag;
648 	bus_space_handle_t h = sc->sc_h;
649 	u_int32_t cfg;
650 
651 	/* Flip the enable bit */
652 	cfg = bus_space_read_4(t, h, GEM_MAC_TX_CONFIG);
653 	cfg &= ~GEM_MAC_TX_ENABLE;
654 	bus_space_write_4(t, h, GEM_MAC_TX_CONFIG, cfg);
655 
656 	/* Wait for it to finish */
657 	return (gem_bitwait(sc, GEM_MAC_TX_CONFIG, GEM_MAC_TX_ENABLE, 0));
658 }
659 
660 /*
661  * Initialize interface.
662  */
663 static int
664 gem_meminit(sc)
665 	struct gem_softc *sc;
666 {
667 	struct gem_rxsoft *rxs;
668 	int i, error;
669 
670 	/*
671 	 * Initialize the transmit descriptor ring.
672 	 */
673 	memset((void *)sc->sc_txdescs, 0, sizeof(sc->sc_txdescs));
674 	for (i = 0; i < GEM_NTXDESC; i++) {
675 		sc->sc_txdescs[i].gd_flags = 0;
676 		sc->sc_txdescs[i].gd_addr = 0;
677 	}
678 	GEM_CDTXSYNC(sc, 0, GEM_NTXDESC,
679 	    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
680 	sc->sc_txfree = GEM_NTXDESC;
681 	sc->sc_txnext = 0;
682 
683 	/*
684 	 * Initialize the receive descriptor and receive job
685 	 * descriptor rings.
686 	 */
687 	for (i = 0; i < GEM_NRXDESC; i++) {
688 		rxs = &sc->sc_rxsoft[i];
689 		if (rxs->rxs_mbuf == NULL) {
690 			if ((error = gem_add_rxbuf(sc, i)) != 0) {
691 				device_printf(sc->sc_dev, "unable to "
692 				    "allocate or map rx buffer %d, error = "
693 				    "%d\n", i, error);
694 				/*
695 				 * XXX Should attempt to run with fewer receive
696 				 * XXX buffers instead of just failing.
697 				 */
698 				gem_rxdrain(sc);
699 				return (1);
700 			}
701 		} else
702 			GEM_INIT_RXDESC(sc, i);
703 	}
704 	sc->sc_rxptr = 0;
705 
706 	return (0);
707 }
708 
709 static int
710 gem_ringsize(sz)
711 	int sz;
712 {
713 	int v = 0;
714 
715 	switch (sz) {
716 	case 32:
717 		v = GEM_RING_SZ_32;
718 		break;
719 	case 64:
720 		v = GEM_RING_SZ_64;
721 		break;
722 	case 128:
723 		v = GEM_RING_SZ_128;
724 		break;
725 	case 256:
726 		v = GEM_RING_SZ_256;
727 		break;
728 	case 512:
729 		v = GEM_RING_SZ_512;
730 		break;
731 	case 1024:
732 		v = GEM_RING_SZ_1024;
733 		break;
734 	case 2048:
735 		v = GEM_RING_SZ_2048;
736 		break;
737 	case 4096:
738 		v = GEM_RING_SZ_4096;
739 		break;
740 	case 8192:
741 		v = GEM_RING_SZ_8192;
742 		break;
743 	default:
744 		printf("gem: invalid Receive Descriptor ring size\n");
745 		break;
746 	}
747 	return (v);
748 }
749 
750 /*
751  * Initialization of interface; set up initialization block
752  * and transmit/receive descriptor rings.
753  */
754 static void
755 gem_init(xsc)
756 	void *xsc;
757 {
758 	struct gem_softc *sc = (struct gem_softc *)xsc;
759 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
760 	bus_space_tag_t t = sc->sc_bustag;
761 	bus_space_handle_t h = sc->sc_h;
762 	int s;
763 	u_int32_t v;
764 
765 	s = splnet();
766 
767 	DPRINTF(sc, ("%s: gem_init: calling stop\n", device_get_name(sc->sc_dev)));
768 	CTR1(KTR_GEM, "%s: gem_init: calling stop", device_get_name(sc->sc_dev));
769 	/*
770 	 * Initialization sequence. The numbered steps below correspond
771 	 * to the sequence outlined in section 6.3.5.1 in the Ethernet
772 	 * Channel Engine manual (part of the PCIO manual).
773 	 * See also the STP2002-STQ document from Sun Microsystems.
774 	 */
775 
776 	/* step 1 & 2. Reset the Ethernet Channel */
777 	gem_stop(&sc->sc_arpcom.ac_if, 0);
778 	gem_reset(sc);
779 	DPRINTF(sc, ("%s: gem_init: restarting\n", device_get_name(sc->sc_dev)));
780 	CTR1(KTR_GEM, "%s: gem_init: restarting", device_get_name(sc->sc_dev));
781 
782 	/* Re-initialize the MIF */
783 	gem_mifinit(sc);
784 
785 	/* Call MI reset function if any */
786 	if (sc->sc_hwreset)
787 		(*sc->sc_hwreset)(sc);
788 
789 	/* step 3. Setup data structures in host memory */
790 	gem_meminit(sc);
791 
792 	/* step 4. TX MAC registers & counters */
793 	gem_init_regs(sc);
794 	/* XXX: VLAN code from NetBSD temporarily removed. */
795 	bus_space_write_4(t, h, GEM_MAC_MAC_MAX_FRAME,
796             (ETHER_MAX_LEN + sizeof(struct ether_header)) | (0x2000<<16));
797 
798 	/* step 5. RX MAC registers & counters */
799 	gem_setladrf(sc);
800 
801 	/* step 6 & 7. Program Descriptor Ring Base Addresses */
802 	/* NOTE: we use only 32-bit DMA addresses here. */
803 	bus_space_write_4(t, h, GEM_TX_RING_PTR_HI, 0);
804 	bus_space_write_4(t, h, GEM_TX_RING_PTR_LO, GEM_CDTXADDR(sc, 0));
805 
806 	bus_space_write_4(t, h, GEM_RX_RING_PTR_HI, 0);
807 	bus_space_write_4(t, h, GEM_RX_RING_PTR_LO, GEM_CDRXADDR(sc, 0));
808 	DPRINTF(sc, ("loading rx ring %lx, tx ring %lx, cddma %lx\n",
809 	    GEM_CDRXADDR(sc, 0), GEM_CDTXADDR(sc, 0), sc->sc_cddma));
810 	CTR3(KTR_GEM, "loading rx ring %lx, tx ring %lx, cddma %lx",
811 	    GEM_CDRXADDR(sc, 0), GEM_CDTXADDR(sc, 0), sc->sc_cddma);
812 
813 	/* step 8. Global Configuration & Interrupt Mask */
814 	bus_space_write_4(t, h, GEM_INTMASK,
815 		      ~(GEM_INTR_TX_INTME|
816 			GEM_INTR_TX_EMPTY|
817 			GEM_INTR_RX_DONE|GEM_INTR_RX_NOBUF|
818 			GEM_INTR_RX_TAG_ERR|GEM_INTR_PCS|
819 			GEM_INTR_MAC_CONTROL|GEM_INTR_MIF|
820 			GEM_INTR_BERR));
821 	bus_space_write_4(t, h, GEM_MAC_RX_MASK, 0); /* XXXX */
822 	bus_space_write_4(t, h, GEM_MAC_TX_MASK, 0xffff); /* XXXX */
823 	bus_space_write_4(t, h, GEM_MAC_CONTROL_MASK, 0); /* XXXX */
824 
825 	/* step 9. ETX Configuration: use mostly default values */
826 
827 	/* Enable DMA */
828 	v = gem_ringsize(GEM_NTXDESC /*XXX*/);
829 	bus_space_write_4(t, h, GEM_TX_CONFIG,
830 		v|GEM_TX_CONFIG_TXDMA_EN|
831 		((0x400<<10)&GEM_TX_CONFIG_TXFIFO_TH));
832 
833 	/* step 10. ERX Configuration */
834 
835 	/* Encode Receive Descriptor ring size: four possible values */
836 	v = gem_ringsize(GEM_NRXDESC /*XXX*/);
837 
838 	/* Enable DMA */
839 	bus_space_write_4(t, h, GEM_RX_CONFIG,
840 		v|(GEM_THRSH_1024<<GEM_RX_CONFIG_FIFO_THRS_SHIFT)|
841 		(2<<GEM_RX_CONFIG_FBOFF_SHFT)|GEM_RX_CONFIG_RXDMA_EN|
842 		(0<<GEM_RX_CONFIG_CXM_START_SHFT));
843 	/*
844 	 * The following value is for an OFF Threshold of about 15.5 Kbytes
845 	 * and an ON Threshold of 4K bytes.
846 	 */
847 	bus_space_write_4(t, h, GEM_RX_PAUSE_THRESH, 0xf8 | (0x40 << 12));
848 	bus_space_write_4(t, h, GEM_RX_BLANKING, (2<<12)|6);
849 
850 	/* step 11. Configure Media */
851 	(void)gem_mii_statchg(sc->sc_dev);
852 
853 	/* step 12. RX_MAC Configuration Register */
854 	v = bus_space_read_4(t, h, GEM_MAC_RX_CONFIG);
855 	v |= GEM_MAC_RX_ENABLE;
856 	bus_space_write_4(t, h, GEM_MAC_RX_CONFIG, v);
857 
858 	/* step 14. Issue Transmit Pending command */
859 
860 	/* Call MI initialization function if any */
861 	if (sc->sc_hwinit)
862 		(*sc->sc_hwinit)(sc);
863 
864 	/* step 15.  Give the reciever a swift kick */
865 	bus_space_write_4(t, h, GEM_RX_KICK, GEM_NRXDESC-4);
866 
867 	/* Start the one second timer. */
868 	callout_reset(&sc->sc_tick_ch, hz, gem_tick, sc);
869 
870 	ifp->if_flags |= IFF_RUNNING;
871 	ifp->if_flags &= ~IFF_OACTIVE;
872 	ifp->if_timer = 0;
873 	sc->sc_flags = ifp->if_flags;
874 	splx(s);
875 }
876 
877 /*
878  * XXX: This is really a substitute for bus_dmamap_load_mbuf(), which FreeBSD
879  * does not yet have, with some adaptions for this driver.
880  * Some changes are mandated by the fact that multiple maps may needed to map
881  * a single mbuf.
882  * It should be removed once generic support is available.
883  *
884  * This is derived from NetBSD (syssrc/sys/arch/sparc64/sparc64/machdep.c), for
885  * a copyright notice see sparc64/sparc64/bus_machdep.c.
886  *
887  * Not every error condition is passed to the callback in this version, and the
888  * callback may be called more than once.
889  * It also gropes in the entails of the callback arg...
890  */
891 static int
892 gem_dmamap_load_mbuf(sc, m0, cb, txj, flags)
893 	struct gem_softc *sc;
894 	struct mbuf *m0;
895 	bus_dmamap_callback_t *cb;
896 	struct gem_txjob *txj;
897 	int flags;
898 {
899 	struct gem_txdma txd;
900 	struct gem_txsoft *txs;
901 	struct mbuf *m;
902 	void  *vaddr;
903 	int error, first = 1, len, totlen;
904 
905 	if ((m0->m_flags & M_PKTHDR) == 0)
906 		panic("gem_dmamap_load_mbuf: no packet header");
907 	totlen = m0->m_pkthdr.len;
908 	len = 0;
909 	txd.txd_sc = sc;
910 	txd.txd_nexttx = txj->txj_nexttx;
911 	txj->txj_nsegs = 0;
912 	STAILQ_INIT(&txj->txj_txsq);
913 	m = m0;
914 	while (m != NULL && len < totlen) {
915 		if (m->m_len == 0)
916 			continue;
917 		/* Get a work queue entry. */
918 		if ((txs = STAILQ_FIRST(&sc->sc_txfreeq)) == NULL) {
919 			/*
920 			 * Ran out of descriptors, return a value that
921 			 * cannot be returned by bus_dmamap_load to notify
922 			 * the caller.
923 			 */
924 			error = -1;
925 			goto fail;
926 		}
927 		len += m->m_len;
928 		txd.txd_flags = first ? GTXD_FIRST : 0;
929 		if (m->m_next == NULL || len >= totlen)
930 			txd.txd_flags |= GTXD_LAST;
931 		vaddr = mtod(m, void *);
932 		error = bus_dmamap_load(sc->sc_dmatag, txs->txs_dmamap, vaddr,
933 		    m->m_len, cb, &txd, flags);
934 		if (error != 0 || txd.txd_error != 0)
935 			goto fail;
936 		/* Sync the DMA map. */
937 		bus_dmamap_sync(sc->sc_dmatag, txs->txs_dmamap,
938 		    BUS_DMASYNC_PREWRITE);
939 		m = m->m_next;
940 		/*
941 		 * Store a pointer to the packet so we can free it later,
942 		 * and remember what txdirty will be once the packet is
943 		 * done.
944 		 */
945 		txs->txs_mbuf = first ? m0 : NULL;
946 		txs->txs_firstdesc = txj->txj_nexttx;
947 		txs->txs_lastdesc = txd.txd_lasttx;
948 		txs->txs_ndescs = txd.txd_nsegs;
949 		CTR3(KTR_GEM, "load_mbuf: setting firstdesc=%d, lastdesc=%d, "
950 		    "ndescs=%d", txs->txs_firstdesc, txs->txs_lastdesc,
951 		    txs->txs_ndescs);
952 		STAILQ_REMOVE_HEAD(&sc->sc_txfreeq, txs_q);
953 		STAILQ_INSERT_TAIL(&txj->txj_txsq, txs, txs_q);
954 		txj->txj_nexttx = txd.txd_nexttx;
955 		txj->txj_nsegs += txd.txd_nsegs;
956 		first = 0;
957 	}
958 	txj->txj_lasttx = txd.txd_lasttx;
959 	return (0);
960 
961 fail:
962 	CTR1(KTR_GEM, "gem_dmamap_load_mbuf failed (%d)", error);
963 	gem_dmamap_unload_mbuf(sc, txj);
964 	return (error);
965 }
966 
967 /*
968  * Unload an mbuf using the txd the information was placed in.
969  * The tx interrupt code frees the tx segments one by one, because the txd is
970  * not available any more.
971  */
972 static void
973 gem_dmamap_unload_mbuf(sc, txj)
974 	struct gem_softc *sc;
975 	struct gem_txjob *txj;
976 {
977 	struct gem_txsoft *txs;
978 
979 	/* Readd the removed descriptors and unload the segments. */
980 	while ((txs = STAILQ_FIRST(&txj->txj_txsq)) != NULL) {
981 		bus_dmamap_unload(sc->sc_dmatag, txs->txs_dmamap);
982 		STAILQ_REMOVE_HEAD(&txj->txj_txsq, txs_q);
983 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
984 	}
985 }
986 
987 static void
988 gem_dmamap_commit_mbuf(sc, txj)
989 	struct gem_softc *sc;
990 	struct gem_txjob *txj;
991 {
992 	struct gem_txsoft *txs;
993 
994 	/* Commit the txjob by transfering the txsoft's to the txdirtyq. */
995 	while ((txs = STAILQ_FIRST(&txj->txj_txsq)) != NULL) {
996 		STAILQ_REMOVE_HEAD(&txj->txj_txsq, txs_q);
997 		STAILQ_INSERT_TAIL(&sc->sc_txdirtyq, txs, txs_q);
998 	}
999 }
1000 
1001 static void
1002 gem_init_regs(sc)
1003 	struct gem_softc *sc;
1004 {
1005 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1006 	bus_space_tag_t t = sc->sc_bustag;
1007 	bus_space_handle_t h = sc->sc_h;
1008 
1009 	/* These regs are not cleared on reset */
1010 	sc->sc_inited = 0;
1011 	if (!sc->sc_inited) {
1012 
1013 		/* Wooo.  Magic values. */
1014 		bus_space_write_4(t, h, GEM_MAC_IPG0, 0);
1015 		bus_space_write_4(t, h, GEM_MAC_IPG1, 8);
1016 		bus_space_write_4(t, h, GEM_MAC_IPG2, 4);
1017 
1018 		bus_space_write_4(t, h, GEM_MAC_MAC_MIN_FRAME, ETHER_MIN_LEN);
1019 		/* Max frame and max burst size */
1020 		bus_space_write_4(t, h, GEM_MAC_MAC_MAX_FRAME,
1021 			(ifp->if_mtu+18) | (0x2000<<16)/* Burst size */);
1022 		bus_space_write_4(t, h, GEM_MAC_PREAMBLE_LEN, 0x7);
1023 		bus_space_write_4(t, h, GEM_MAC_JAM_SIZE, 0x4);
1024 		bus_space_write_4(t, h, GEM_MAC_ATTEMPT_LIMIT, 0x10);
1025 		/* Dunno.... */
1026 		bus_space_write_4(t, h, GEM_MAC_CONTROL_TYPE, 0x8088);
1027 		bus_space_write_4(t, h, GEM_MAC_RANDOM_SEED,
1028 			((sc->sc_arpcom.ac_enaddr[5]<<8)|
1029 			  sc->sc_arpcom.ac_enaddr[4])&0x3ff);
1030 		/* Secondary MAC addr set to 0:0:0:0:0:0 */
1031 		bus_space_write_4(t, h, GEM_MAC_ADDR3, 0);
1032 		bus_space_write_4(t, h, GEM_MAC_ADDR4, 0);
1033 		bus_space_write_4(t, h, GEM_MAC_ADDR5, 0);
1034 		/* MAC control addr set to 0:1:c2:0:1:80 */
1035 		bus_space_write_4(t, h, GEM_MAC_ADDR6, 0x0001);
1036 		bus_space_write_4(t, h, GEM_MAC_ADDR7, 0xc200);
1037 		bus_space_write_4(t, h, GEM_MAC_ADDR8, 0x0180);
1038 
1039 		/* MAC filter addr set to 0:0:0:0:0:0 */
1040 		bus_space_write_4(t, h, GEM_MAC_ADDR_FILTER0, 0);
1041 		bus_space_write_4(t, h, GEM_MAC_ADDR_FILTER1, 0);
1042 		bus_space_write_4(t, h, GEM_MAC_ADDR_FILTER2, 0);
1043 
1044 		bus_space_write_4(t, h, GEM_MAC_ADR_FLT_MASK1_2, 0);
1045 		bus_space_write_4(t, h, GEM_MAC_ADR_FLT_MASK0, 0);
1046 
1047 		sc->sc_inited = 1;
1048 	}
1049 
1050 	/* Counters need to be zeroed */
1051 	bus_space_write_4(t, h, GEM_MAC_NORM_COLL_CNT, 0);
1052 	bus_space_write_4(t, h, GEM_MAC_FIRST_COLL_CNT, 0);
1053 	bus_space_write_4(t, h, GEM_MAC_EXCESS_COLL_CNT, 0);
1054 	bus_space_write_4(t, h, GEM_MAC_LATE_COLL_CNT, 0);
1055 	bus_space_write_4(t, h, GEM_MAC_DEFER_TMR_CNT, 0);
1056 	bus_space_write_4(t, h, GEM_MAC_PEAK_ATTEMPTS, 0);
1057 	bus_space_write_4(t, h, GEM_MAC_RX_FRAME_COUNT, 0);
1058 	bus_space_write_4(t, h, GEM_MAC_RX_LEN_ERR_CNT, 0);
1059 	bus_space_write_4(t, h, GEM_MAC_RX_ALIGN_ERR, 0);
1060 	bus_space_write_4(t, h, GEM_MAC_RX_CRC_ERR_CNT, 0);
1061 	bus_space_write_4(t, h, GEM_MAC_RX_CODE_VIOL, 0);
1062 
1063 	/* Un-pause stuff */
1064 #if 0
1065 	bus_space_write_4(t, h, GEM_MAC_SEND_PAUSE_CMD, 0x1BF0);
1066 #else
1067 	bus_space_write_4(t, h, GEM_MAC_SEND_PAUSE_CMD, 0);
1068 #endif
1069 
1070 	/*
1071 	 * Set the station address.
1072 	 */
1073 	bus_space_write_4(t, h, GEM_MAC_ADDR0,
1074 		(sc->sc_arpcom.ac_enaddr[4]<<8) | sc->sc_arpcom.ac_enaddr[5]);
1075 	bus_space_write_4(t, h, GEM_MAC_ADDR1,
1076 		(sc->sc_arpcom.ac_enaddr[2]<<8) | sc->sc_arpcom.ac_enaddr[3]);
1077 	bus_space_write_4(t, h, GEM_MAC_ADDR2,
1078 		(sc->sc_arpcom.ac_enaddr[0]<<8) | sc->sc_arpcom.ac_enaddr[1]);
1079 }
1080 
1081 static void
1082 gem_start(ifp)
1083 	struct ifnet *ifp;
1084 {
1085 	struct gem_softc *sc = (struct gem_softc *)ifp->if_softc;
1086 	struct mbuf *m0 = NULL, *m;
1087 	struct gem_txjob txj;
1088 	int firsttx, ofree, seg, ntx, txmfail;
1089 
1090 	if ((ifp->if_flags & (IFF_RUNNING | IFF_OACTIVE)) != IFF_RUNNING)
1091 		return;
1092 
1093 	/*
1094 	 * Remember the previous number of free descriptors and
1095 	 * the first descriptor we'll use.
1096 	 */
1097 	ofree = sc->sc_txfree;
1098 	firsttx = sc->sc_txnext;
1099 
1100 	DPRINTF(sc, ("%s: gem_start: txfree %d, txnext %d\n",
1101 	    device_get_name(sc->sc_dev), ofree, firsttx));
1102 	CTR3(KTR_GEM, "%s: gem_start: txfree %d, txnext %d",
1103 	    device_get_name(sc->sc_dev), ofree, firsttx);
1104 
1105 	txj.txj_nexttx = firsttx;
1106 	txj.txj_lasttx = 0;
1107 	/*
1108 	 * Loop through the send queue, setting up transmit descriptors
1109 	 * until we drain the queue, or use up all available transmit
1110 	 * descriptors.
1111 	 */
1112 	txmfail = 0;
1113 	for (ntx = 0;; ntx++) {
1114 		/*
1115 		 * Grab a packet off the queue.
1116 		 */
1117 		IF_DEQUEUE(&ifp->if_snd, m0);
1118 		if (m0 == NULL)
1119 			break;
1120 		m = NULL;
1121 
1122 		/*
1123 		 * Load the DMA map.  If this fails, the packet either
1124 		 * didn't fit in the alloted number of segments, or we were
1125 		 * short on resources.  In this case, we'll copy and try
1126 		 * again.
1127 		 */
1128 		txmfail = gem_dmamap_load_mbuf(sc, m0,
1129 		    gem_txdma_callback, &txj, BUS_DMA_NOWAIT);
1130 		if (txmfail == -1) {
1131 			IF_PREPEND(&ifp->if_snd, m0);
1132 			break;
1133 		}
1134 		if (txmfail > 0) {
1135 			MGETHDR(m, M_DONTWAIT, MT_DATA);
1136 			if (m == NULL) {
1137 				device_printf(sc->sc_dev, "unable to "
1138 				    "allocate Tx mbuf\n");
1139 				/* Failed; requeue. */
1140 				IF_PREPEND(&ifp->if_snd, m0);
1141 				break;
1142 			}
1143 			if (m0->m_pkthdr.len > MHLEN) {
1144 				MCLGET(m, M_DONTWAIT);
1145 				if ((m->m_flags & M_EXT) == 0) {
1146 					device_printf(sc->sc_dev, "unable to "
1147 					    "allocate Tx cluster\n");
1148 					IF_PREPEND(&ifp->if_snd, m0);
1149 					m_freem(m);
1150 					break;
1151 				}
1152 			}
1153 			m_copydata(m0, 0, m0->m_pkthdr.len, mtod(m, caddr_t));
1154 			m->m_pkthdr.len = m->m_len = m0->m_pkthdr.len;
1155 			txmfail = gem_dmamap_load_mbuf(sc, m,
1156 			    gem_txdma_callback, &txj, BUS_DMA_NOWAIT);
1157 			if (txmfail != 0) {
1158 				if (txmfail > 0) {
1159 					device_printf(sc->sc_dev, "unable to "
1160 					    "load Tx buffer, error = %d\n",
1161 					    txmfail);
1162 				}
1163 				m_freem(m);
1164 				IF_PREPEND(&ifp->if_snd, m0);
1165 				break;
1166 			}
1167 		}
1168 
1169 		/*
1170 		 * Ensure we have enough descriptors free to describe
1171 		 * the packet.  Note, we always reserve one descriptor
1172 		 * at the end of the ring as a termination point, to
1173 		 * prevent wrap-around.
1174 		 */
1175 		if (txj.txj_nsegs > (sc->sc_txfree - 1)) {
1176 			/*
1177 			 * Not enough free descriptors to transmit this
1178 			 * packet.  We haven't committed to anything yet,
1179 			 * so just unload the DMA map, put the packet
1180 			 * back on the queue, and punt.  Notify the upper
1181 			 * layer that there are no more slots left.
1182 			 *
1183 			 * XXX We could allocate an mbuf and copy, but
1184 			 * XXX it is worth it?
1185 			 */
1186 			ifp->if_flags |= IFF_OACTIVE;
1187 			gem_dmamap_unload_mbuf(sc, &txj);
1188 			if (m != NULL)
1189 				m_freem(m);
1190 			IF_PREPEND(&ifp->if_snd, m0);
1191 			break;
1192 		}
1193 
1194 		if (m != NULL)
1195 			m_freem(m0);
1196 
1197 		/*
1198 		 * WE ARE NOW COMMITTED TO TRANSMITTING THE PACKET.
1199 		 */
1200 
1201 #ifdef GEM_DEBUG
1202 		if (ifp->if_flags & IFF_DEBUG) {
1203 			printf("     gem_start %p transmit chain:\n",
1204 			    STAILQ_FIRST(&txj.txj_txsq));
1205 			for (seg = sc->sc_txnext;; seg = GEM_NEXTTX(seg)) {
1206 				printf("descriptor %d:\t", seg);
1207 				printf("gd_flags:   0x%016llx\t", (long long)
1208 					GEM_DMA_READ(sc, sc->sc_txdescs[seg].gd_flags));
1209 				printf("gd_addr: 0x%016llx\n", (long long)
1210 					GEM_DMA_READ(sc, sc->sc_txdescs[seg].gd_addr));
1211 				if (seg == txj.txj_lasttx)
1212 					break;
1213 			}
1214 		}
1215 #endif
1216 
1217 		/* Sync the descriptors we're using. */
1218 		GEM_CDTXSYNC(sc, sc->sc_txnext, txj.txj_nsegs,
1219 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
1220 
1221 		/* Advance the tx pointer. */
1222 		sc->sc_txfree -= txj.txj_nsegs;
1223 		sc->sc_txnext = txj.txj_nexttx;
1224 
1225 		gem_dmamap_commit_mbuf(sc, &txj);
1226 	}
1227 
1228 	if (txmfail == -1 || sc->sc_txfree == 0) {
1229 		ifp->if_flags |= IFF_OACTIVE;
1230 		/* No more slots left; notify upper layer. */
1231 	}
1232 
1233 	if (ntx > 0) {
1234 		DPRINTF(sc, ("%s: packets enqueued, IC on %d, OWN on %d\n",
1235 		    device_get_name(sc->sc_dev), txj.txj_lasttx, firsttx));
1236 		CTR3(KTR_GEM, "%s: packets enqueued, IC on %d, OWN on %d",
1237 		    device_get_name(sc->sc_dev), txj.txj_lasttx, firsttx);
1238 		/*
1239 		 * The entire packet chain is set up.
1240 		 * Kick the transmitter.
1241 		 */
1242 		DPRINTF(sc, ("%s: gem_start: kicking tx %d\n",
1243 			device_get_name(sc->sc_dev), txj.txj_nexttx));
1244 		CTR3(KTR_GEM, "%s: gem_start: kicking tx %d=%d",
1245 		    device_get_name(sc->sc_dev), txj.txj_nexttx,
1246 		    sc->sc_txnext);
1247 		bus_space_write_4(sc->sc_bustag, sc->sc_h, GEM_TX_KICK,
1248 			sc->sc_txnext);
1249 
1250 		/* Set a watchdog timer in case the chip flakes out. */
1251 		ifp->if_timer = 5;
1252 		DPRINTF(sc, ("%s: gem_start: watchdog %d\n",
1253 			device_get_name(sc->sc_dev), ifp->if_timer));
1254 		CTR2(KTR_GEM, "%s: gem_start: watchdog %d",
1255 			device_get_name(sc->sc_dev), ifp->if_timer);
1256 	}
1257 }
1258 
1259 /*
1260  * Transmit interrupt.
1261  */
1262 static void
1263 gem_tint(sc)
1264 	struct gem_softc *sc;
1265 {
1266 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1267 	bus_space_tag_t t = sc->sc_bustag;
1268 	bus_space_handle_t mac = sc->sc_h;
1269 	struct gem_txsoft *txs;
1270 	int txlast;
1271 
1272 
1273 	DPRINTF(sc, ("%s: gem_tint\n", device_get_name(sc->sc_dev)));
1274 	CTR1(KTR_GEM, "%s: gem_tint", device_get_name(sc->sc_dev));
1275 
1276 	/*
1277 	 * Unload collision counters
1278 	 */
1279 	ifp->if_collisions +=
1280 		bus_space_read_4(t, mac, GEM_MAC_NORM_COLL_CNT) +
1281 		bus_space_read_4(t, mac, GEM_MAC_FIRST_COLL_CNT) +
1282 		bus_space_read_4(t, mac, GEM_MAC_EXCESS_COLL_CNT) +
1283 		bus_space_read_4(t, mac, GEM_MAC_LATE_COLL_CNT);
1284 
1285 	/*
1286 	 * then clear the hardware counters.
1287 	 */
1288 	bus_space_write_4(t, mac, GEM_MAC_NORM_COLL_CNT, 0);
1289 	bus_space_write_4(t, mac, GEM_MAC_FIRST_COLL_CNT, 0);
1290 	bus_space_write_4(t, mac, GEM_MAC_EXCESS_COLL_CNT, 0);
1291 	bus_space_write_4(t, mac, GEM_MAC_LATE_COLL_CNT, 0);
1292 
1293 	/*
1294 	 * Go through our Tx list and free mbufs for those
1295 	 * frames that have been transmitted.
1296 	 */
1297 	while ((txs = STAILQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
1298 		GEM_CDTXSYNC(sc, txs->txs_lastdesc,
1299 		    txs->txs_ndescs,
1300 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1301 
1302 #ifdef GEM_DEBUG
1303 		if (ifp->if_flags & IFF_DEBUG) {
1304 			int i;
1305 			printf("    txsoft %p transmit chain:\n", txs);
1306 			for (i = txs->txs_firstdesc;; i = GEM_NEXTTX(i)) {
1307 				printf("descriptor %d: ", i);
1308 				printf("gd_flags: 0x%016llx\t", (long long)
1309 					GEM_DMA_READ(sc, sc->sc_txdescs[i].gd_flags));
1310 				printf("gd_addr: 0x%016llx\n", (long long)
1311 					GEM_DMA_READ(sc, sc->sc_txdescs[i].gd_addr));
1312 				if (i == txs->txs_lastdesc)
1313 					break;
1314 			}
1315 		}
1316 #endif
1317 
1318 		/*
1319 		 * In theory, we could harveast some descriptors before
1320 		 * the ring is empty, but that's a bit complicated.
1321 		 *
1322 		 * GEM_TX_COMPLETION points to the last descriptor
1323 		 * processed +1.
1324 		 */
1325 		txlast = bus_space_read_4(t, mac, GEM_TX_COMPLETION);
1326 		DPRINTF(sc,
1327 			("gem_tint: txs->txs_lastdesc = %d, txlast = %d\n",
1328 				txs->txs_lastdesc, txlast));
1329 		CTR3(KTR_GEM, "gem_tint: txs->txs_firstdesc = %d, "
1330 		    "txs->txs_lastdesc = %d, txlast = %d",
1331 		    txs->txs_firstdesc, txs->txs_lastdesc, txlast);
1332 		if (txs->txs_firstdesc <= txs->txs_lastdesc) {
1333 			if ((txlast >= txs->txs_firstdesc) &&
1334 				(txlast <= txs->txs_lastdesc))
1335 				break;
1336 		} else {
1337 			/* Ick -- this command wraps */
1338 			if ((txlast >= txs->txs_firstdesc) ||
1339 				(txlast <= txs->txs_lastdesc))
1340 				break;
1341 		}
1342 
1343 		DPRINTF(sc, ("gem_tint: releasing a desc\n"));
1344 		CTR0(KTR_GEM, "gem_tint: releasing a desc");
1345 		STAILQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs_q);
1346 
1347 		sc->sc_txfree += txs->txs_ndescs;
1348 
1349 		bus_dmamap_sync(sc->sc_dmatag, txs->txs_dmamap,
1350 		    BUS_DMASYNC_POSTWRITE);
1351 		bus_dmamap_unload(sc->sc_dmatag, txs->txs_dmamap);
1352 		if (txs->txs_mbuf != NULL) {
1353 			m_freem(txs->txs_mbuf);
1354 			txs->txs_mbuf = NULL;
1355 		}
1356 
1357 		STAILQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
1358 
1359 		ifp->if_opackets++;
1360 	}
1361 
1362 	DPRINTF(sc, ("gem_tint: GEM_TX_STATE_MACHINE %x "
1363 		"GEM_TX_DATA_PTR %llx "
1364 		"GEM_TX_COMPLETION %x\n",
1365 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_TX_STATE_MACHINE),
1366 		((long long) bus_space_read_4(sc->sc_bustag, sc->sc_h,
1367 			GEM_TX_DATA_PTR_HI) << 32) |
1368 			     bus_space_read_4(sc->sc_bustag, sc->sc_h,
1369 			GEM_TX_DATA_PTR_LO),
1370 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_TX_COMPLETION)));
1371 	CTR3(KTR_GEM, "gem_tint: GEM_TX_STATE_MACHINE %x "
1372 		"GEM_TX_DATA_PTR %llx "
1373 		"GEM_TX_COMPLETION %x",
1374 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_TX_STATE_MACHINE),
1375 		((long long) bus_space_read_4(sc->sc_bustag, sc->sc_h,
1376 			GEM_TX_DATA_PTR_HI) << 32) |
1377 			     bus_space_read_4(sc->sc_bustag, sc->sc_h,
1378 			GEM_TX_DATA_PTR_LO),
1379 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_TX_COMPLETION));
1380 
1381 	if (STAILQ_FIRST(&sc->sc_txdirtyq) == NULL)
1382 		ifp->if_timer = 0;
1383 
1384 
1385 	DPRINTF(sc, ("%s: gem_tint: watchdog %d\n",
1386 		device_get_name(sc->sc_dev), ifp->if_timer));
1387 	CTR2(KTR_GEM, "%s: gem_tint: watchdog %d",
1388 		device_get_name(sc->sc_dev), ifp->if_timer);
1389 
1390 	/* Freed some descriptors, so reset IFF_OACTIVE and restart. */
1391 	ifp->if_flags &= ~IFF_OACTIVE;
1392 	gem_start(ifp);
1393 }
1394 
1395 /*
1396  * Receive interrupt.
1397  */
1398 static void
1399 gem_rint(sc)
1400 	struct gem_softc *sc;
1401 {
1402 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1403 	bus_space_tag_t t = sc->sc_bustag;
1404 	bus_space_handle_t h = sc->sc_h;
1405 	struct ether_header *eh;
1406 	struct gem_rxsoft *rxs;
1407 	struct mbuf *m;
1408 	u_int64_t rxstat;
1409 	int i, len;
1410 
1411 	DPRINTF(sc, ("%s: gem_rint\n", device_get_name(sc->sc_dev)));
1412 	CTR1(KTR_GEM, "%s: gem_rint", device_get_name(sc->sc_dev));
1413 	/*
1414 	 * XXXX Read the lastrx only once at the top for speed.
1415 	 */
1416 	DPRINTF(sc, ("gem_rint: sc->rxptr %d, complete %d\n",
1417 		sc->sc_rxptr, bus_space_read_4(t, h, GEM_RX_COMPLETION)));
1418 	CTR2(KTR_GEM, "gem_rint: sc->rxptr %d, complete %d",
1419 	    sc->sc_rxptr, bus_space_read_4(t, h, GEM_RX_COMPLETION));
1420 	for (i = sc->sc_rxptr; i != bus_space_read_4(t, h, GEM_RX_COMPLETION);
1421 	     i = GEM_NEXTRX(i)) {
1422 		rxs = &sc->sc_rxsoft[i];
1423 
1424 		GEM_CDRXSYNC(sc, i,
1425 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1426 
1427 		rxstat = GEM_DMA_READ(sc, sc->sc_rxdescs[i].gd_flags);
1428 
1429 		if (rxstat & GEM_RD_OWN) {
1430 			printf("gem_rint: completed descriptor "
1431 				"still owned %d\n", i);
1432 			/*
1433 			 * We have processed all of the receive buffers.
1434 			 */
1435 			break;
1436 		}
1437 
1438 		if (rxstat & GEM_RD_BAD_CRC) {
1439 			device_printf(sc->sc_dev, "receive error: CRC error\n");
1440 			GEM_INIT_RXDESC(sc, i);
1441 			continue;
1442 		}
1443 
1444 		bus_dmamap_sync(sc->sc_dmatag, rxs->rxs_dmamap,
1445 		    BUS_DMASYNC_POSTREAD);
1446 #ifdef GEM_DEBUG
1447 		if (ifp->if_flags & IFF_DEBUG) {
1448 			printf("    rxsoft %p descriptor %d: ", rxs, i);
1449 			printf("gd_flags: 0x%016llx\t", (long long)
1450 				GEM_DMA_READ(sc, sc->sc_rxdescs[i].gd_flags));
1451 			printf("gd_addr: 0x%016llx\n", (long long)
1452 				GEM_DMA_READ(sc, sc->sc_rxdescs[i].gd_addr));
1453 		}
1454 #endif
1455 
1456 		/*
1457 		 * No errors; receive the packet.  Note the Gem
1458 		 * includes the CRC with every packet.
1459 		 */
1460 		len = GEM_RD_BUFLEN(rxstat);
1461 
1462 		/*
1463 		 * Allocate a new mbuf cluster.  If that fails, we are
1464 		 * out of memory, and must drop the packet and recycle
1465 		 * the buffer that's already attached to this descriptor.
1466 		 */
1467 		m = rxs->rxs_mbuf;
1468 		if (gem_add_rxbuf(sc, i) != 0) {
1469 			ifp->if_ierrors++;
1470 			GEM_INIT_RXDESC(sc, i);
1471 			bus_dmamap_sync(sc->sc_dmatag, rxs->rxs_dmamap,
1472 			    BUS_DMASYNC_PREREAD);
1473 			continue;
1474 		}
1475 		m->m_data += 2; /* We're already off by two */
1476 
1477 		ifp->if_ipackets++;
1478 		eh = mtod(m, struct ether_header *);
1479 		m->m_pkthdr.rcvif = ifp;
1480 		m->m_pkthdr.len = m->m_len = len - ETHER_CRC_LEN;
1481 		m_adj(m, sizeof(struct ether_header));
1482 
1483 		/* Pass it on. */
1484 		ether_input(ifp, eh, m);
1485 	}
1486 
1487 	/* Update the receive pointer. */
1488 	sc->sc_rxptr = i;
1489 	bus_space_write_4(t, h, GEM_RX_KICK, i);
1490 
1491 	DPRINTF(sc, ("gem_rint: done sc->rxptr %d, complete %d\n",
1492 		sc->sc_rxptr, bus_space_read_4(t, h, GEM_RX_COMPLETION)));
1493 	CTR2(KTR_GEM, "gem_rint: done sc->rxptr %d, complete %d",
1494 		sc->sc_rxptr, bus_space_read_4(t, h, GEM_RX_COMPLETION));
1495 
1496 }
1497 
1498 
1499 /*
1500  * gem_add_rxbuf:
1501  *
1502  *	Add a receive buffer to the indicated descriptor.
1503  */
1504 static int
1505 gem_add_rxbuf(sc, idx)
1506 	struct gem_softc *sc;
1507 	int idx;
1508 {
1509 	struct gem_rxsoft *rxs = &sc->sc_rxsoft[idx];
1510 	struct mbuf *m;
1511 	int error;
1512 
1513 	MGETHDR(m, M_DONTWAIT, MT_DATA);
1514 	if (m == NULL)
1515 		return (ENOBUFS);
1516 
1517 	MCLGET(m, M_DONTWAIT);
1518 	if ((m->m_flags & M_EXT) == 0) {
1519 		m_freem(m);
1520 		return (ENOBUFS);
1521 	}
1522 
1523 #ifdef GEM_DEBUG
1524 	/* bzero the packet to check dma */
1525 	memset(m->m_ext.ext_buf, 0, m->m_ext.ext_size);
1526 #endif
1527 
1528 	if (rxs->rxs_mbuf != NULL)
1529 		bus_dmamap_unload(sc->sc_dmatag, rxs->rxs_dmamap);
1530 
1531 	rxs->rxs_mbuf = m;
1532 
1533 	error = bus_dmamap_load(sc->sc_dmatag, rxs->rxs_dmamap,
1534 	    m->m_ext.ext_buf, m->m_ext.ext_size, gem_rxdma_callback, rxs,
1535 	    BUS_DMA_NOWAIT);
1536 	if (error != 0 || rxs->rxs_paddr == 0) {
1537 		device_printf(sc->sc_dev, "can't load rx DMA map %d, error = "
1538 		    "%d\n", idx, error);
1539 		panic("gem_add_rxbuf");	/* XXX */
1540 	}
1541 
1542 	bus_dmamap_sync(sc->sc_dmatag, rxs->rxs_dmamap, BUS_DMASYNC_PREREAD);
1543 
1544 	GEM_INIT_RXDESC(sc, idx);
1545 
1546 	return (0);
1547 }
1548 
1549 
1550 static void
1551 gem_eint(sc, status)
1552 	struct gem_softc *sc;
1553 	u_int status;
1554 {
1555 
1556 	if ((status & GEM_INTR_MIF) != 0) {
1557 		device_printf(sc->sc_dev, "XXXlink status changed\n");
1558 		return;
1559 	}
1560 
1561 	device_printf(sc->sc_dev, "status=%x\n", status);
1562 }
1563 
1564 
1565 void
1566 gem_intr(v)
1567 	void *v;
1568 {
1569 	struct gem_softc *sc = (struct gem_softc *)v;
1570 	bus_space_tag_t t = sc->sc_bustag;
1571 	bus_space_handle_t seb = sc->sc_h;
1572 	u_int32_t status;
1573 
1574 	status = bus_space_read_4(t, seb, GEM_STATUS);
1575 	DPRINTF(sc, ("%s: gem_intr: cplt %x, status %x\n",
1576 		device_get_name(sc->sc_dev), (status>>19),
1577 		(u_int)status));
1578 	CTR3(KTR_GEM, "%s: gem_intr: cplt %x, status %x",
1579 		device_get_name(sc->sc_dev), (status>>19),
1580 		(u_int)status);
1581 
1582 	if ((status & (GEM_INTR_RX_TAG_ERR | GEM_INTR_BERR)) != 0)
1583 		gem_eint(sc, status);
1584 
1585 	if ((status & (GEM_INTR_TX_EMPTY | GEM_INTR_TX_INTME)) != 0)
1586 		gem_tint(sc);
1587 
1588 	if ((status & (GEM_INTR_RX_DONE | GEM_INTR_RX_NOBUF)) != 0)
1589 		gem_rint(sc);
1590 
1591 	/* We should eventually do more than just print out error stats. */
1592 	if (status & GEM_INTR_TX_MAC) {
1593 		int txstat = bus_space_read_4(t, seb, GEM_MAC_TX_STATUS);
1594 		if (txstat & ~GEM_MAC_TX_XMIT_DONE)
1595 			printf("MAC tx fault, status %x\n", txstat);
1596 	}
1597 	if (status & GEM_INTR_RX_MAC) {
1598 		int rxstat = bus_space_read_4(t, seb, GEM_MAC_RX_STATUS);
1599 		if (rxstat & ~(GEM_MAC_RX_DONE | GEM_MAC_RX_FRAME_CNT))
1600 			printf("MAC rx fault, status %x\n", rxstat);
1601 	}
1602 }
1603 
1604 
1605 static void
1606 gem_watchdog(ifp)
1607 	struct ifnet *ifp;
1608 {
1609 	struct gem_softc *sc = ifp->if_softc;
1610 
1611 	DPRINTF(sc, ("gem_watchdog: GEM_RX_CONFIG %x GEM_MAC_RX_STATUS %x "
1612 		"GEM_MAC_RX_CONFIG %x\n",
1613 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_RX_CONFIG),
1614 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_MAC_RX_STATUS),
1615 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_MAC_RX_CONFIG)));
1616 	CTR3(KTR_GEM, "gem_watchdog: GEM_RX_CONFIG %x GEM_MAC_RX_STATUS %x "
1617 		"GEM_MAC_RX_CONFIG %x",
1618 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_RX_CONFIG),
1619 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_MAC_RX_STATUS),
1620 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_MAC_RX_CONFIG));
1621 	CTR3(KTR_GEM, "gem_watchdog: GEM_TX_CONFIG %x GEM_MAC_TX_STATUS %x "
1622 		"GEM_MAC_TX_CONFIG %x",
1623 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_TX_CONFIG),
1624 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_MAC_TX_STATUS),
1625 		bus_space_read_4(sc->sc_bustag, sc->sc_h, GEM_MAC_TX_CONFIG));
1626 
1627 	device_printf(sc->sc_dev, "device timeout\n");
1628 	++ifp->if_oerrors;
1629 
1630 	/* Try to get more packets going. */
1631 	gem_start(ifp);
1632 }
1633 
1634 /*
1635  * Initialize the MII Management Interface
1636  */
1637 static void
1638 gem_mifinit(sc)
1639 	struct gem_softc *sc;
1640 {
1641 	bus_space_tag_t t = sc->sc_bustag;
1642 	bus_space_handle_t mif = sc->sc_h;
1643 
1644 	/* Configure the MIF in frame mode */
1645 	sc->sc_mif_config = bus_space_read_4(t, mif, GEM_MIF_CONFIG);
1646 	sc->sc_mif_config &= ~GEM_MIF_CONFIG_BB_ENA;
1647 	bus_space_write_4(t, mif, GEM_MIF_CONFIG, sc->sc_mif_config);
1648 }
1649 
1650 /*
1651  * MII interface
1652  *
1653  * The GEM MII interface supports at least three different operating modes:
1654  *
1655  * Bitbang mode is implemented using data, clock and output enable registers.
1656  *
1657  * Frame mode is implemented by loading a complete frame into the frame
1658  * register and polling the valid bit for completion.
1659  *
1660  * Polling mode uses the frame register but completion is indicated by
1661  * an interrupt.
1662  *
1663  */
1664 int
1665 gem_mii_readreg(dev, phy, reg)
1666 	device_t dev;
1667 	int phy, reg;
1668 {
1669 	struct gem_softc *sc = device_get_softc(dev);
1670 	bus_space_tag_t t = sc->sc_bustag;
1671 	bus_space_handle_t mif = sc->sc_h;
1672 	int n;
1673 	u_int32_t v;
1674 
1675 #ifdef GEM_DEBUG_PHY
1676 	printf("gem_mii_readreg: phy %d reg %d\n", phy, reg);
1677 #endif
1678 
1679 #if 0
1680 	/* Select the desired PHY in the MIF configuration register */
1681 	v = bus_space_read_4(t, mif, GEM_MIF_CONFIG);
1682 	/* Clear PHY select bit */
1683 	v &= ~GEM_MIF_CONFIG_PHY_SEL;
1684 	if (phy == GEM_PHYAD_EXTERNAL)
1685 		/* Set PHY select bit to get at external device */
1686 		v |= GEM_MIF_CONFIG_PHY_SEL;
1687 	bus_space_write_4(t, mif, GEM_MIF_CONFIG, v);
1688 #endif
1689 
1690 	/* Construct the frame command */
1691 	v = (reg << GEM_MIF_REG_SHIFT)	| (phy << GEM_MIF_PHY_SHIFT) |
1692 		GEM_MIF_FRAME_READ;
1693 
1694 	bus_space_write_4(t, mif, GEM_MIF_FRAME, v);
1695 	for (n = 0; n < 100; n++) {
1696 		DELAY(1);
1697 		v = bus_space_read_4(t, mif, GEM_MIF_FRAME);
1698 		if (v & GEM_MIF_FRAME_TA0)
1699 			return (v & GEM_MIF_FRAME_DATA);
1700 	}
1701 
1702 	device_printf(sc->sc_dev, "mii_read timeout\n");
1703 	return (0);
1704 }
1705 
1706 int
1707 gem_mii_writereg(dev, phy, reg, val)
1708 	device_t dev;
1709 	int phy, reg, val;
1710 {
1711 	struct gem_softc *sc = device_get_softc(dev);
1712 	bus_space_tag_t t = sc->sc_bustag;
1713 	bus_space_handle_t mif = sc->sc_h;
1714 	int n;
1715 	u_int32_t v;
1716 
1717 #ifdef GEM_DEBUG_PHY
1718 	printf("gem_mii_writereg: phy %d reg %d val %x\n", phy, reg, val);
1719 #endif
1720 
1721 #if 0
1722 	/* Select the desired PHY in the MIF configuration register */
1723 	v = bus_space_read_4(t, mif, GEM_MIF_CONFIG);
1724 	/* Clear PHY select bit */
1725 	v &= ~GEM_MIF_CONFIG_PHY_SEL;
1726 	if (phy == GEM_PHYAD_EXTERNAL)
1727 		/* Set PHY select bit to get at external device */
1728 		v |= GEM_MIF_CONFIG_PHY_SEL;
1729 	bus_space_write_4(t, mif, GEM_MIF_CONFIG, v);
1730 #endif
1731 	/* Construct the frame command */
1732 	v = GEM_MIF_FRAME_WRITE			|
1733 	    (phy << GEM_MIF_PHY_SHIFT)		|
1734 	    (reg << GEM_MIF_REG_SHIFT)		|
1735 	    (val & GEM_MIF_FRAME_DATA);
1736 
1737 	bus_space_write_4(t, mif, GEM_MIF_FRAME, v);
1738 	for (n = 0; n < 100; n++) {
1739 		DELAY(1);
1740 		v = bus_space_read_4(t, mif, GEM_MIF_FRAME);
1741 		if (v & GEM_MIF_FRAME_TA0)
1742 			return (1);
1743 	}
1744 
1745 	device_printf(sc->sc_dev, "mii_write timeout\n");
1746 	return (0);
1747 }
1748 
1749 void
1750 gem_mii_statchg(dev)
1751 	device_t dev;
1752 {
1753 	struct gem_softc *sc = device_get_softc(dev);
1754 #ifdef GEM_DEBUG
1755 	int instance = IFM_INST(sc->sc_mii->mii_media.ifm_cur->ifm_media);
1756 #endif
1757 	bus_space_tag_t t = sc->sc_bustag;
1758 	bus_space_handle_t mac = sc->sc_h;
1759 	u_int32_t v;
1760 
1761 #ifdef GEM_DEBUG
1762 	if (sc->sc_debug)
1763 		printf("gem_mii_statchg: status change: phy = %d\n",
1764 			sc->sc_phys[instance]);
1765 #endif
1766 
1767 	/* Set tx full duplex options */
1768 	bus_space_write_4(t, mac, GEM_MAC_TX_CONFIG, 0);
1769 	DELAY(10000); /* reg must be cleared and delay before changing. */
1770 	v = GEM_MAC_TX_ENA_IPG0|GEM_MAC_TX_NGU|GEM_MAC_TX_NGU_LIMIT|
1771 		GEM_MAC_TX_ENABLE;
1772 	if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) != 0) {
1773 		v |= GEM_MAC_TX_IGN_CARRIER|GEM_MAC_TX_IGN_COLLIS;
1774 	}
1775 	bus_space_write_4(t, mac, GEM_MAC_TX_CONFIG, v);
1776 
1777 	/* XIF Configuration */
1778  /* We should really calculate all this rather than rely on defaults */
1779 	v = bus_space_read_4(t, mac, GEM_MAC_XIF_CONFIG);
1780 	v = GEM_MAC_XIF_LINK_LED;
1781 	v |= GEM_MAC_XIF_TX_MII_ENA;
1782 	/* If an external transceiver is connected, enable its MII drivers */
1783 	sc->sc_mif_config = bus_space_read_4(t, mac, GEM_MIF_CONFIG);
1784 	if ((sc->sc_mif_config & GEM_MIF_CONFIG_MDI1) != 0) {
1785 		/* External MII needs echo disable if half duplex. */
1786 		if ((IFM_OPTIONS(sc->sc_mii->mii_media_active) & IFM_FDX) != 0)
1787 			/* turn on full duplex LED */
1788 			v |= GEM_MAC_XIF_FDPLX_LED;
1789  			else
1790 	 			/* half duplex -- disable echo */
1791 		 		v |= GEM_MAC_XIF_ECHO_DISABL;
1792 	} else {
1793 		/* Internal MII needs buf enable */
1794 		v |= GEM_MAC_XIF_MII_BUF_ENA;
1795 	}
1796 	bus_space_write_4(t, mac, GEM_MAC_XIF_CONFIG, v);
1797 }
1798 
1799 int
1800 gem_mediachange(ifp)
1801 	struct ifnet *ifp;
1802 {
1803 	struct gem_softc *sc = ifp->if_softc;
1804 
1805 	/* XXX Add support for serial media. */
1806 
1807 	return (mii_mediachg(sc->sc_mii));
1808 }
1809 
1810 void
1811 gem_mediastatus(ifp, ifmr)
1812 	struct ifnet *ifp;
1813 	struct ifmediareq *ifmr;
1814 {
1815 	struct gem_softc *sc = ifp->if_softc;
1816 
1817 	if ((ifp->if_flags & IFF_UP) == 0)
1818 		return;
1819 
1820 	mii_pollstat(sc->sc_mii);
1821 	ifmr->ifm_active = sc->sc_mii->mii_media_active;
1822 	ifmr->ifm_status = sc->sc_mii->mii_media_status;
1823 }
1824 
1825 /*
1826  * Process an ioctl request.
1827  */
1828 static int
1829 gem_ioctl(ifp, cmd, data)
1830 	struct ifnet *ifp;
1831 	u_long cmd;
1832 	caddr_t data;
1833 {
1834 	struct gem_softc *sc = ifp->if_softc;
1835 	struct ifreq *ifr = (struct ifreq *)data;
1836 	int s, error = 0;
1837 
1838 	switch (cmd) {
1839 	case SIOCSIFADDR:
1840 	case SIOCGIFADDR:
1841 	case SIOCSIFMTU:
1842 		error = ether_ioctl(ifp, cmd, data);
1843 		break;
1844 	case SIOCSIFFLAGS:
1845 		if (ifp->if_flags & IFF_UP) {
1846 			if ((sc->sc_flags ^ ifp->if_flags) == IFF_PROMISC)
1847 				gem_setladrf(sc);
1848 			else
1849 				gem_init(sc);
1850 		} else {
1851 			if (ifp->if_flags & IFF_RUNNING)
1852 				gem_stop(ifp, 0);
1853 		}
1854 		sc->sc_flags = ifp->if_flags;
1855 		error = 0;
1856 		break;
1857 	case SIOCADDMULTI:
1858 	case SIOCDELMULTI:
1859 		gem_setladrf(sc);
1860 		error = 0;
1861 		break;
1862 	case SIOCGIFMEDIA:
1863 	case SIOCSIFMEDIA:
1864 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii->mii_media, cmd);
1865 		break;
1866 	default:
1867 		error = ENOTTY;
1868 		break;
1869 	}
1870 
1871 	/* Try to get things going again */
1872 	if (ifp->if_flags & IFF_UP)
1873 		gem_start(ifp);
1874 	splx(s);
1875 	return (error);
1876 }
1877 
1878 /*
1879  * Set up the logical address filter.
1880  */
1881 static void
1882 gem_setladrf(sc)
1883 	struct gem_softc *sc;
1884 {
1885 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1886 	struct ifmultiaddr *inm;
1887 	struct sockaddr_dl *sdl;
1888 	bus_space_tag_t t = sc->sc_bustag;
1889 	bus_space_handle_t h = sc->sc_h;
1890 	u_char *cp;
1891 	u_int32_t crc;
1892 	u_int32_t hash[16];
1893 	u_int32_t v;
1894 	int len;
1895 
1896 	/* Clear hash table */
1897 	memset(hash, 0, sizeof(hash));
1898 
1899 	/* Get current RX configuration */
1900 	v = bus_space_read_4(t, h, GEM_MAC_RX_CONFIG);
1901 
1902 	if ((ifp->if_flags & IFF_PROMISC) != 0) {
1903 		/* Turn on promiscuous mode; turn off the hash filter */
1904 		v |= GEM_MAC_RX_PROMISCUOUS;
1905 		v &= ~GEM_MAC_RX_HASH_FILTER;
1906 		;
1907 		goto chipit;
1908 	}
1909 	if ((ifp->if_flags & IFF_ALLMULTI) != 0) {
1910 		hash[3] = hash[2] = hash[1] = hash[0] = 0xffff;
1911 		ifp->if_flags |= IFF_ALLMULTI;
1912 		goto chipit;
1913 	}
1914 
1915 	/* Turn off promiscuous mode; turn on the hash filter */
1916 	v &= ~GEM_MAC_RX_PROMISCUOUS;
1917 	v |= GEM_MAC_RX_HASH_FILTER;
1918 
1919 	/*
1920 	 * Set up multicast address filter by passing all multicast addresses
1921 	 * through a crc generator, and then using the high order 6 bits as an
1922 	 * index into the 256 bit logical address filter.  The high order bit
1923 	 * selects the word, while the rest of the bits select the bit within
1924 	 * the word.
1925 	 */
1926 
1927 	TAILQ_FOREACH(inm, &sc->sc_arpcom.ac_if.if_multiaddrs, ifma_link) {
1928 		if (inm->ifma_addr->sa_family != AF_LINK)
1929 			continue;
1930 		sdl = (struct sockaddr_dl *)inm->ifma_addr;
1931 		cp = LLADDR(sdl);
1932 		crc = 0xffffffff;
1933 		for (len = sdl->sdl_alen; --len >= 0;) {
1934 			int octet = *cp++;
1935 			int i;
1936 
1937 #define MC_POLY_LE	0xedb88320UL	/* mcast crc, little endian */
1938 			for (i = 0; i < 8; i++) {
1939 				if ((crc & 1) ^ (octet & 1)) {
1940 					crc >>= 1;
1941 					crc ^= MC_POLY_LE;
1942 				} else {
1943 					crc >>= 1;
1944 				}
1945 				octet >>= 1;
1946 			}
1947 		}
1948 		/* Just want the 8 most significant bits. */
1949 		crc >>= 24;
1950 
1951 		/* Set the corresponding bit in the filter. */
1952 		hash[crc >> 4] |= 1 << (crc & 0xf);
1953 	}
1954 
1955 chipit:
1956 	/* Now load the hash table into the chip */
1957 	bus_space_write_4(t, h, GEM_MAC_HASH0, hash[0]);
1958 	bus_space_write_4(t, h, GEM_MAC_HASH1, hash[1]);
1959 	bus_space_write_4(t, h, GEM_MAC_HASH2, hash[2]);
1960 	bus_space_write_4(t, h, GEM_MAC_HASH3, hash[3]);
1961 	bus_space_write_4(t, h, GEM_MAC_HASH4, hash[4]);
1962 	bus_space_write_4(t, h, GEM_MAC_HASH5, hash[5]);
1963 	bus_space_write_4(t, h, GEM_MAC_HASH6, hash[6]);
1964 	bus_space_write_4(t, h, GEM_MAC_HASH7, hash[7]);
1965 	bus_space_write_4(t, h, GEM_MAC_HASH8, hash[8]);
1966 	bus_space_write_4(t, h, GEM_MAC_HASH9, hash[9]);
1967 	bus_space_write_4(t, h, GEM_MAC_HASH10, hash[10]);
1968 	bus_space_write_4(t, h, GEM_MAC_HASH11, hash[11]);
1969 	bus_space_write_4(t, h, GEM_MAC_HASH12, hash[12]);
1970 	bus_space_write_4(t, h, GEM_MAC_HASH13, hash[13]);
1971 	bus_space_write_4(t, h, GEM_MAC_HASH14, hash[14]);
1972 	bus_space_write_4(t, h, GEM_MAC_HASH15, hash[15]);
1973 
1974 	bus_space_write_4(t, h, GEM_MAC_RX_CONFIG, v);
1975 }
1976 
1977 #if notyet
1978 
1979 /*
1980  * gem_power:
1981  *
1982  *	Power management (suspend/resume) hook.
1983  */
1984 void
1985 static gem_power(why, arg)
1986 	int why;
1987 	void *arg;
1988 {
1989 	struct gem_softc *sc = arg;
1990 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1991 	int s;
1992 
1993 	s = splnet();
1994 	switch (why) {
1995 	case PWR_SUSPEND:
1996 	case PWR_STANDBY:
1997 		gem_stop(ifp, 1);
1998 		if (sc->sc_power != NULL)
1999 			(*sc->sc_power)(sc, why);
2000 		break;
2001 	case PWR_RESUME:
2002 		if (ifp->if_flags & IFF_UP) {
2003 			if (sc->sc_power != NULL)
2004 				(*sc->sc_power)(sc, why);
2005 			gem_init(ifp);
2006 		}
2007 		break;
2008 	case PWR_SOFTSUSPEND:
2009 	case PWR_SOFTSTANDBY:
2010 	case PWR_SOFTRESUME:
2011 		break;
2012 	}
2013 	splx(s);
2014 }
2015 #endif
2016