xref: /openbsd-src/sys/dev/pci/if_stge.c (revision d13be5d47e4149db2549a9828e244d59dbc43f15)
1 /*	$OpenBSD: if_stge.c,v 1.53 2011/04/05 18:01:21 henning Exp $	*/
2 /*	$NetBSD: if_stge.c,v 1.27 2005/05/16 21:35:32 bouyer Exp $	*/
3 
4 /*-
5  * Copyright (c) 2001 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Jason R. Thorpe.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 /*
34  * Device driver for the Sundance Tech. TC9021 10/100/1000
35  * Ethernet controller.
36  */
37 
38 #include "bpfilter.h"
39 #include "vlan.h"
40 
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/timeout.h>
44 #include <sys/mbuf.h>
45 #include <sys/malloc.h>
46 #include <sys/kernel.h>
47 #include <sys/socket.h>
48 #include <sys/ioctl.h>
49 #include <sys/errno.h>
50 #include <sys/device.h>
51 #include <sys/queue.h>
52 
53 #include <net/if.h>
54 #include <net/if_dl.h>
55 
56 #ifdef INET
57 #include <netinet/in.h>
58 #include <netinet/in_systm.h>
59 #include <netinet/in_var.h>
60 #include <netinet/ip.h>
61 #include <netinet/if_ether.h>
62 #endif
63 
64 #include <net/if_media.h>
65 
66 #if NVLAN > 0
67 #include <net/if_types.h>
68 #include <net/if_vlan_var.h>
69 #endif
70 
71 #if NBPFILTER > 0
72 #include <net/bpf.h>
73 #endif
74 
75 #include <machine/bus.h>
76 #include <machine/intr.h>
77 
78 #include <dev/mii/mii.h>
79 #include <dev/mii/miivar.h>
80 #include <dev/mii/mii_bitbang.h>
81 
82 #include <dev/pci/pcireg.h>
83 #include <dev/pci/pcivar.h>
84 #include <dev/pci/pcidevs.h>
85 
86 #include <dev/pci/if_stgereg.h>
87 
88 void	stge_start(struct ifnet *);
89 void	stge_watchdog(struct ifnet *);
90 int	stge_ioctl(struct ifnet *, u_long, caddr_t);
91 int	stge_init(struct ifnet *);
92 void	stge_stop(struct ifnet *, int);
93 
94 void	stge_reset(struct stge_softc *);
95 void	stge_rxdrain(struct stge_softc *);
96 int	stge_add_rxbuf(struct stge_softc *, int);
97 void	stge_read_eeprom(struct stge_softc *, int, uint16_t *);
98 void	stge_tick(void *);
99 
100 void	stge_stats_update(struct stge_softc *);
101 
102 void	stge_iff(struct stge_softc *);
103 
104 int	stge_intr(void *);
105 void	stge_txintr(struct stge_softc *);
106 void	stge_rxintr(struct stge_softc *);
107 
108 int	stge_mii_readreg(struct device *, int, int);
109 void	stge_mii_writereg(struct device *, int, int, int);
110 void	stge_mii_statchg(struct device *);
111 
112 int	stge_mediachange(struct ifnet *);
113 void	stge_mediastatus(struct ifnet *, struct ifmediareq *);
114 
115 int	stge_match(struct device *, void *, void *);
116 void	stge_attach(struct device *, struct device *, void *);
117 
118 int	stge_copy_small = 0;
119 
120 struct cfattach stge_ca = {
121 	sizeof(struct stge_softc), stge_match, stge_attach,
122 };
123 
124 struct cfdriver stge_cd = {
125 	NULL, "stge", DV_IFNET
126 };
127 
128 uint32_t stge_mii_bitbang_read(struct device *);
129 void	stge_mii_bitbang_write(struct device *, uint32_t);
130 
131 const struct mii_bitbang_ops stge_mii_bitbang_ops = {
132 	stge_mii_bitbang_read,
133 	stge_mii_bitbang_write,
134 	{
135 		PC_MgmtData,		/* MII_BIT_MDO */
136 		PC_MgmtData,		/* MII_BIT_MDI */
137 		PC_MgmtClk,		/* MII_BIT_MDC */
138 		PC_MgmtDir,		/* MII_BIT_DIR_HOST_PHY */
139 		0,			/* MII_BIT_DIR_PHY_HOST */
140 	}
141 };
142 
143 /*
144  * Devices supported by this driver.
145  */
146 const struct pci_matchid stge_devices[] = {
147 	{ PCI_VENDOR_ANTARES, PCI_PRODUCT_ANTARES_TC9021 },
148 	{ PCI_VENDOR_DLINK, PCI_PRODUCT_DLINK_DGE550T },
149 	{ PCI_VENDOR_SUNDANCE, PCI_PRODUCT_SUNDANCE_ST1023 },
150 	{ PCI_VENDOR_SUNDANCE, PCI_PRODUCT_SUNDANCE_ST2021 },
151 	{ PCI_VENDOR_SUNDANCE, PCI_PRODUCT_SUNDANCE_TC9021 },
152 	{ PCI_VENDOR_SUNDANCE, PCI_PRODUCT_SUNDANCE_TC9021_ALT },
153 	{ PCI_VENDOR_TAMARACK, PCI_PRODUCT_TAMARACK_TC9021 },
154 	{ PCI_VENDOR_TAMARACK, PCI_PRODUCT_TAMARACK_TC9021_ALT }
155 };
156 
157 int
158 stge_match(struct device *parent, void *match, void *aux)
159 {
160 	return (pci_matchbyid((struct pci_attach_args *)aux, stge_devices,
161 	    sizeof(stge_devices) / sizeof(stge_devices[0])));
162 }
163 
164 void
165 stge_attach(struct device *parent, struct device *self, void *aux)
166 {
167 	struct stge_softc *sc = (struct stge_softc *) self;
168 	struct pci_attach_args *pa = aux;
169 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
170 	pci_chipset_tag_t pc = pa->pa_pc;
171 	pci_intr_handle_t ih;
172 	const char *intrstr = NULL;
173 	bus_space_tag_t iot, memt;
174 	bus_space_handle_t ioh, memh;
175 	bus_dma_segment_t seg;
176 	bus_size_t iosize;
177 	int ioh_valid, memh_valid;
178 	int i, rseg, error;
179 	int state;
180 
181 	timeout_set(&sc->sc_timeout, stge_tick, sc);
182 
183 	sc->sc_rev = PCI_REVISION(pa->pa_class);
184 
185 	/*
186 	 * Map the device.
187 	 */
188 	ioh_valid = (pci_mapreg_map(pa, STGE_PCI_IOBA,
189 	    PCI_MAPREG_TYPE_IO, 0,
190 	    &iot, &ioh, NULL, &iosize, 0) == 0);
191 	memh_valid = (pci_mapreg_map(pa, STGE_PCI_MMBA,
192 	    PCI_MAPREG_TYPE_MEM|PCI_MAPREG_MEM_TYPE_32BIT, 0,
193 	    &memt, &memh, NULL, &iosize, 0) == 0);
194 
195 	if (memh_valid) {
196 		sc->sc_st = memt;
197 		sc->sc_sh = memh;
198 	} else if (ioh_valid) {
199 		sc->sc_st = iot;
200 		sc->sc_sh = ioh;
201 	} else {
202 		printf(": unable to map device registers\n");
203 		return;
204 	}
205 
206 	sc->sc_dmat = pa->pa_dmat;
207 
208 	/* Get it out of power save mode if needed. */
209 	state = pci_set_powerstate(pc, pa->pa_tag, PCI_PMCSR_STATE_D0);
210 	if (state == PCI_PMCSR_STATE_D3) {
211 		/*
212 		 * The card has lost all configuration data in
213 		 * this state, so punt.
214 		 */
215 		printf(": unable to wake up from power state D3, "
216 		    "reboot required.\n");
217 		return;
218 	}
219 
220 	/*
221 	 * Map and establish our interrupt.
222 	 */
223 	if (pci_intr_map(pa, &ih)) {
224 		printf(": unable to map interrupt\n");
225 		goto fail_0;
226 	}
227 	intrstr = pci_intr_string(pc, ih);
228 	sc->sc_ih = pci_intr_establish(pc, ih, IPL_NET, stge_intr, sc,
229 				       sc->sc_dev.dv_xname);
230 	if (sc->sc_ih == NULL) {
231 		printf(": unable to establish interrupt");
232 		if (intrstr != NULL)
233 			printf(" at %s", intrstr);
234 		printf("\n");
235 		goto fail_0;
236 	}
237 	printf(": %s", intrstr);
238 
239 	/*
240 	 * Allocate the control data structures, and create and load the
241 	 * DMA map for it.
242 	 */
243 	if ((error = bus_dmamem_alloc(sc->sc_dmat,
244 	    sizeof(struct stge_control_data), PAGE_SIZE, 0, &seg, 1, &rseg,
245 	    0)) != 0) {
246 		printf("%s: unable to allocate control data, error = %d\n",
247 		    sc->sc_dev.dv_xname, error);
248 		goto fail_0;
249 	}
250 
251 	if ((error = bus_dmamem_map(sc->sc_dmat, &seg, rseg,
252 	    sizeof(struct stge_control_data), (caddr_t *)&sc->sc_control_data,
253 	    BUS_DMA_COHERENT)) != 0) {
254 		printf("%s: unable to map control data, error = %d\n",
255 		    sc->sc_dev.dv_xname, error);
256 		goto fail_1;
257 	}
258 
259 	if ((error = bus_dmamap_create(sc->sc_dmat,
260 	    sizeof(struct stge_control_data), 1,
261 	    sizeof(struct stge_control_data), 0, 0, &sc->sc_cddmamap)) != 0) {
262 		printf("%s: unable to create control data DMA map, "
263 		    "error = %d\n", sc->sc_dev.dv_xname, error);
264 		goto fail_2;
265 	}
266 
267 	if ((error = bus_dmamap_load(sc->sc_dmat, sc->sc_cddmamap,
268 	    sc->sc_control_data, sizeof(struct stge_control_data), NULL,
269 	    0)) != 0) {
270 		printf("%s: unable to load control data DMA map, error = %d\n",
271 		    sc->sc_dev.dv_xname, error);
272 		goto fail_3;
273 	}
274 
275 	/*
276 	 * Create the transmit buffer DMA maps.  Note that rev B.3
277 	 * and earlier seem to have a bug regarding multi-fragment
278 	 * packets.  We need to limit the number of Tx segments on
279 	 * such chips to 1.
280 	 */
281 	for (i = 0; i < STGE_NTXDESC; i++) {
282 		if ((error = bus_dmamap_create(sc->sc_dmat,
283 		    STGE_JUMBO_FRAMELEN, STGE_NTXFRAGS, MCLBYTES, 0, 0,
284 		    &sc->sc_txsoft[i].ds_dmamap)) != 0) {
285 			printf("%s: unable to create tx DMA map %d, "
286 			    "error = %d\n", sc->sc_dev.dv_xname, i, error);
287 			goto fail_4;
288 		}
289 	}
290 
291 	/*
292 	 * Create the receive buffer DMA maps.
293 	 */
294 	for (i = 0; i < STGE_NRXDESC; i++) {
295 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES, 1,
296 		    MCLBYTES, 0, 0, &sc->sc_rxsoft[i].ds_dmamap)) != 0) {
297 			printf("%s: unable to create rx DMA map %d, "
298 			    "error = %d\n", sc->sc_dev.dv_xname, i, error);
299 			goto fail_5;
300 		}
301 		sc->sc_rxsoft[i].ds_mbuf = NULL;
302 	}
303 
304 	/*
305 	 * Determine if we're copper or fiber.  It affects how we
306 	 * reset the card.
307 	 */
308 	if (CSR_READ_4(sc, STGE_AsicCtrl) & AC_PhyMedia)
309 		sc->sc_usefiber = 1;
310 	else
311 		sc->sc_usefiber = 0;
312 
313 	/*
314 	 * Reset the chip to a known state.
315 	 */
316 	stge_reset(sc);
317 
318 	/*
319 	 * Reading the station address from the EEPROM doesn't seem
320 	 * to work, at least on my sample boards.  Instead, since
321 	 * the reset sequence does AutoInit, read it from the station
322 	 * address registers. For Sundance 1023 you can only read it
323 	 * from EEPROM.
324 	 */
325 	if (PCI_PRODUCT(pa->pa_id) != PCI_PRODUCT_SUNDANCE_ST1023) {
326 		sc->sc_arpcom.ac_enaddr[0] = CSR_READ_2(sc,
327 		    STGE_StationAddress0) & 0xff;
328 		sc->sc_arpcom.ac_enaddr[1] = CSR_READ_2(sc,
329 		    STGE_StationAddress0) >> 8;
330 		sc->sc_arpcom.ac_enaddr[2] = CSR_READ_2(sc,
331 		    STGE_StationAddress1) & 0xff;
332 		sc->sc_arpcom.ac_enaddr[3] = CSR_READ_2(sc,
333 		    STGE_StationAddress1) >> 8;
334 		sc->sc_arpcom.ac_enaddr[4] = CSR_READ_2(sc,
335 		    STGE_StationAddress2) & 0xff;
336 		sc->sc_arpcom.ac_enaddr[5] = CSR_READ_2(sc,
337 		    STGE_StationAddress2) >> 8;
338 		sc->sc_stge1023 = 0;
339 	} else {
340 		uint16_t myaddr[ETHER_ADDR_LEN / 2];
341 		for (i = 0; i < ETHER_ADDR_LEN / 2; i++) {
342 			stge_read_eeprom(sc, STGE_EEPROM_StationAddress0 + i,
343 			    &myaddr[i]);
344 			myaddr[i] = letoh16(myaddr[i]);
345 		}
346 		(void)memcpy(sc->sc_arpcom.ac_enaddr, myaddr,
347 		    sizeof(sc->sc_arpcom.ac_enaddr));
348 		sc->sc_stge1023 = 1;
349 	}
350 
351 	printf(", address %s\n", ether_sprintf(sc->sc_arpcom.ac_enaddr));
352 
353 	/*
354 	 * Read some important bits from the PhyCtrl register.
355 	 */
356 	sc->sc_PhyCtrl = CSR_READ_1(sc, STGE_PhyCtrl) &
357 	    (PC_PhyDuplexPolarity | PC_PhyLnkPolarity);
358 
359 	/*
360 	 * Initialize our media structures and probe the MII.
361 	 */
362 	sc->sc_mii.mii_ifp = ifp;
363 	sc->sc_mii.mii_readreg = stge_mii_readreg;
364 	sc->sc_mii.mii_writereg = stge_mii_writereg;
365 	sc->sc_mii.mii_statchg = stge_mii_statchg;
366 	ifmedia_init(&sc->sc_mii.mii_media, 0, stge_mediachange,
367 	    stge_mediastatus);
368 	mii_attach(&sc->sc_dev, &sc->sc_mii, 0xffffffff, MII_PHY_ANY,
369 	    MII_OFFSET_ANY, MIIF_DOPAUSE);
370 	if (LIST_FIRST(&sc->sc_mii.mii_phys) == NULL) {
371 		ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE, 0, NULL);
372 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE);
373 	} else
374 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_AUTO);
375 
376 	ifp = &sc->sc_arpcom.ac_if;
377 	strlcpy(ifp->if_xname, sc->sc_dev.dv_xname, sizeof ifp->if_xname);
378 	ifp->if_softc = sc;
379 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
380 	ifp->if_ioctl = stge_ioctl;
381 	ifp->if_start = stge_start;
382 	ifp->if_watchdog = stge_watchdog;
383 #ifdef STGE_JUMBO
384 	ifp->if_hardmtu = STGE_JUMBO_MTU;
385 #endif
386 	IFQ_SET_MAXLEN(&ifp->if_snd, STGE_NTXDESC - 1);
387 	IFQ_SET_READY(&ifp->if_snd);
388 
389 	ifp->if_capabilities = IFCAP_VLAN_MTU;
390 
391 #if NVLAN > 0
392 	ifp->if_capabilities |= IFCAP_VLAN_HWTAGGING;
393 #endif
394 
395 	/*
396 	 * The manual recommends disabling early transmit, so we
397 	 * do.  It's disabled anyway, if using IP checksumming,
398 	 * since the entire packet must be in the FIFO in order
399 	 * for the chip to perform the checksum.
400 	 */
401 	sc->sc_txthresh = 0x0fff;
402 
403 	/*
404 	 * Disable MWI if the PCI layer tells us to.
405 	 */
406 	sc->sc_DMACtrl = 0;
407 #ifdef fake
408 	if ((pa->pa_flags & PCI_FLAGS_MWI_OKAY) == 0)
409 		sc->sc_DMACtrl |= DMAC_MWIDisable;
410 #endif
411 
412 #ifdef STGE_CHECKSUM
413 	/*
414 	 * We can do IPv4/TCPv4/UDPv4 checksums in hardware.
415 	 */
416 	sc->sc_arpcom.ac_if.if_capabilities |= IFCAP_CSUM_IPv4 |
417 	    IFCAP_CSUM_TCPv4 | IFCAP_CSUM_UDPv4;
418 #endif
419 
420 	/*
421 	 * Attach the interface.
422 	 */
423 	if_attach(ifp);
424 	ether_ifattach(ifp);
425 	return;
426 
427 	/*
428 	 * Free any resources we've allocated during the failed attach
429 	 * attempt.  Do this in reverse order and fall through.
430 	 */
431  fail_5:
432 	for (i = 0; i < STGE_NRXDESC; i++) {
433 		if (sc->sc_rxsoft[i].ds_dmamap != NULL)
434 			bus_dmamap_destroy(sc->sc_dmat,
435 			    sc->sc_rxsoft[i].ds_dmamap);
436 	}
437  fail_4:
438 	for (i = 0; i < STGE_NTXDESC; i++) {
439 		if (sc->sc_txsoft[i].ds_dmamap != NULL)
440 			bus_dmamap_destroy(sc->sc_dmat,
441 			    sc->sc_txsoft[i].ds_dmamap);
442 	}
443 	bus_dmamap_unload(sc->sc_dmat, sc->sc_cddmamap);
444  fail_3:
445 	bus_dmamap_destroy(sc->sc_dmat, sc->sc_cddmamap);
446  fail_2:
447 	bus_dmamem_unmap(sc->sc_dmat, (caddr_t)sc->sc_control_data,
448 	    sizeof(struct stge_control_data));
449  fail_1:
450 	bus_dmamem_free(sc->sc_dmat, &seg, rseg);
451  fail_0:
452 	bus_space_unmap(sc->sc_st, sc->sc_sh, iosize);
453 	return;
454 }
455 
456 static void
457 stge_dma_wait(struct stge_softc *sc)
458 {
459 	int i;
460 
461 	for (i = 0; i < STGE_TIMEOUT; i++) {
462 		delay(2);
463 		if ((CSR_READ_4(sc, STGE_DMACtrl) & DMAC_TxDMAInProg) == 0)
464 			break;
465 	}
466 
467 	if (i == STGE_TIMEOUT)
468 		printf("%s: DMA wait timed out\n", sc->sc_dev.dv_xname);
469 }
470 
471 /*
472  * stge_start:		[ifnet interface function]
473  *
474  *	Start packet transmission on the interface.
475  */
476 void
477 stge_start(struct ifnet *ifp)
478 {
479 	struct stge_softc *sc = ifp->if_softc;
480 	struct mbuf *m0;
481 	struct stge_descsoft *ds;
482 	struct stge_tfd *tfd;
483 	bus_dmamap_t dmamap;
484 	int error, firsttx, nexttx, opending, seg, totlen;
485 	uint64_t csum_flags = 0, tfc;
486 
487 	if ((ifp->if_flags & (IFF_RUNNING|IFF_OACTIVE)) != IFF_RUNNING)
488 		return;
489 
490 	/*
491 	 * Remember the previous number of pending transmissions
492 	 * and the first descriptor we will use.
493 	 */
494 	opending = sc->sc_txpending;
495 	firsttx = STGE_NEXTTX(sc->sc_txlast);
496 
497 	/*
498 	 * Loop through the send queue, setting up transmit descriptors
499 	 * until we drain the queue, or use up all available transmit
500 	 * descriptors.
501 	 */
502 	for (;;) {
503 		/*
504 		 * Grab a packet off the queue.
505 		 */
506 		IFQ_POLL(&ifp->if_snd, m0);
507 		if (m0 == NULL)
508 			break;
509 
510 		/*
511 		 * Leave one unused descriptor at the end of the
512 		 * list to prevent wrapping completely around.
513 		 */
514 		if (sc->sc_txpending == (STGE_NTXDESC - 1))
515 			break;
516 
517 		/*
518 		 * Get the last and next available transmit descriptor.
519 		 */
520 		nexttx = STGE_NEXTTX(sc->sc_txlast);
521 		tfd = &sc->sc_txdescs[nexttx];
522 		ds = &sc->sc_txsoft[nexttx];
523 
524 		dmamap = ds->ds_dmamap;
525 
526 		/*
527 		 * Load the DMA map.  If this fails, the packet either
528 		 * didn't fit in the alloted number of segments, or we
529 		 * were short on resources.  For the too-many-segments
530 		 * case, we simply report an error and drop the packet,
531 		 * since we can't sanely copy a jumbo packet to a single
532 		 * buffer.
533 		 */
534 		error = bus_dmamap_load_mbuf(sc->sc_dmat, dmamap, m0,
535 		    BUS_DMA_NOWAIT);
536 		if (error) {
537 			if (error == EFBIG) {
538 				printf("%s: Tx packet consumes too many "
539 				    "DMA segments (%u), dropping...\n",
540 				    sc->sc_dev.dv_xname, dmamap->dm_nsegs);
541 				IFQ_DEQUEUE(&ifp->if_snd, m0);
542 				m_freem(m0);
543 				continue;
544 			}
545 			/*
546 			 * Short on resources, just stop for now.
547 			 */
548 			break;
549 		}
550 
551 		IFQ_DEQUEUE(&ifp->if_snd, m0);
552 
553 		/*
554 		 * WE ARE NOW COMMITTED TO TRANSMITTING THE PACKET.
555 		 */
556 
557 		/* Sync the DMA map. */
558 		bus_dmamap_sync(sc->sc_dmat, dmamap, 0, dmamap->dm_mapsize,
559 		    BUS_DMASYNC_PREWRITE);
560 
561 		/* Initialize the fragment list. */
562 		for (totlen = 0, seg = 0; seg < dmamap->dm_nsegs; seg++) {
563 			tfd->tfd_frags[seg].frag_word0 =
564 			    htole64(FRAG_ADDR(dmamap->dm_segs[seg].ds_addr) |
565 			    FRAG_LEN(dmamap->dm_segs[seg].ds_len));
566 			totlen += dmamap->dm_segs[seg].ds_len;
567 		}
568 
569 #ifdef STGE_CHECKSUM
570 		/*
571 		 * Initialize checksumming flags in the descriptor.
572 		 * Byte-swap constants so the compiler can optimize.
573 		 */
574 		if (m0->m_pkthdr.csum_flags & M_IPV4_CSUM_OUT)
575 			csum_flags |= TFD_IPChecksumEnable;
576 
577 		if (m0->m_pkthdr.csum_flags & M_TCP_CSUM_OUT)
578 			csum_flags |= TFD_TCPChecksumEnable;
579 		else if (m0->m_pkthdr.csum_flags & M_UDP_CSUM_OUT)
580 			csum_flags |= TFD_UDPChecksumEnable;
581 #endif
582 
583 		/*
584 		 * Initialize the descriptor and give it to the chip.
585 		 */
586 		tfc = TFD_FrameId(nexttx) | TFD_WordAlign(/*totlen & */3) |
587 		    TFD_FragCount(seg) | csum_flags;
588 		if ((nexttx & STGE_TXINTR_SPACING_MASK) == 0)
589 			tfc |= TFD_TxDMAIndicate;
590 
591 #if NVLAN > 0
592 		/* Check if we have a VLAN tag to insert. */
593 		if (m0->m_flags & M_VLANTAG)
594 			tfc |= (TFD_VLANTagInsert |
595 			    TFD_VID(m0->m_pkthdr.ether_vtag));
596 #endif
597 
598 		tfd->tfd_control = htole64(tfc);
599 
600 		/* Sync the descriptor. */
601 		STGE_CDTXSYNC(sc, nexttx,
602 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
603 
604 		/*
605 		 * Kick the transmit DMA logic.
606 		 */
607 		CSR_WRITE_4(sc, STGE_DMACtrl,
608 		    sc->sc_DMACtrl | DMAC_TxDMAPollNow);
609 
610 		/*
611 		 * Store a pointer to the packet so we can free it later.
612 		 */
613 		ds->ds_mbuf = m0;
614 
615 		/* Advance the tx pointer. */
616 		sc->sc_txpending++;
617 		sc->sc_txlast = nexttx;
618 
619 #if NBPFILTER > 0
620 		/*
621 		 * Pass the packet to any BPF listeners.
622 		 */
623 		if (ifp->if_bpf)
624 			bpf_mtap_ether(ifp->if_bpf, m0, BPF_DIRECTION_OUT);
625 #endif /* NBPFILTER > 0 */
626 	}
627 
628 	if (sc->sc_txpending == (STGE_NTXDESC - 1)) {
629 		/* No more slots left; notify upper layer. */
630 		ifp->if_flags |= IFF_OACTIVE;
631 	}
632 
633 	if (sc->sc_txpending != opending) {
634 		/*
635 		 * We enqueued packets.  If the transmitter was idle,
636 		 * reset the txdirty pointer.
637 		 */
638 		if (opending == 0)
639 			sc->sc_txdirty = firsttx;
640 
641 		/* Set a watchdog timer in case the chip flakes out. */
642 		ifp->if_timer = 5;
643 	}
644 }
645 
646 /*
647  * stge_watchdog:	[ifnet interface function]
648  *
649  *	Watchdog timer handler.
650  */
651 void
652 stge_watchdog(struct ifnet *ifp)
653 {
654 	struct stge_softc *sc = ifp->if_softc;
655 
656 	/*
657 	 * Sweep up first, since we don't interrupt every frame.
658 	 */
659 	stge_txintr(sc);
660 	if (sc->sc_txpending != 0) {
661 		printf("%s: device timeout\n", sc->sc_dev.dv_xname);
662 		ifp->if_oerrors++;
663 
664 		(void) stge_init(ifp);
665 
666 		/* Try to get more packets going. */
667 		stge_start(ifp);
668 	}
669 }
670 
671 /*
672  * stge_ioctl:		[ifnet interface function]
673  *
674  *	Handle control requests from the operator.
675  */
676 int
677 stge_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
678 {
679 	struct stge_softc *sc = ifp->if_softc;
680 	struct ifaddr *ifa = (struct ifaddr *)data;
681 	struct ifreq *ifr = (struct ifreq *)data;
682 	int s, error = 0;
683 
684 	s = splnet();
685 
686 	switch (cmd) {
687 	case SIOCSIFADDR:
688 		ifp->if_flags |= IFF_UP;
689 		if (!(ifp->if_flags & IFF_RUNNING))
690 			stge_init(ifp);
691 
692 #ifdef INET
693 		if (ifa->ifa_addr->sa_family == AF_INET)
694 			arp_ifinit(&sc->sc_arpcom, ifa);
695 #endif
696 		break;
697 
698 	case SIOCSIFFLAGS:
699 		if (ifp->if_flags & IFF_UP) {
700 			if (ifp->if_flags & IFF_RUNNING)
701 				error = ENETRESET;
702 			else
703 				stge_init(ifp);
704 		} else {
705 			if (ifp->if_flags & IFF_RUNNING)
706 				stge_stop(ifp, 1);
707 		}
708 		break;
709 
710 	case SIOCSIFMEDIA:
711 	case SIOCGIFMEDIA:
712 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii.mii_media, cmd);
713 		break;
714 
715 	default:
716 		error = ether_ioctl(ifp, &sc->sc_arpcom, cmd, data);
717 	}
718 
719 	if (error == ENETRESET) {
720 		if (ifp->if_flags & IFF_RUNNING)
721 			stge_iff(sc);
722 		error = 0;
723 	}
724 
725 	/* Try to get more packets going. */
726 	stge_start(ifp);
727 
728 	splx(s);
729 	return (error);
730 }
731 
732 /*
733  * stge_intr:
734  *
735  *	Interrupt service routine.
736  */
737 int
738 stge_intr(void *arg)
739 {
740 	struct stge_softc *sc = arg;
741 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
742 	uint32_t txstat;
743 	int wantinit;
744 	uint16_t isr;
745 
746 	if ((CSR_READ_2(sc, STGE_IntStatus) & IS_InterruptStatus) == 0)
747 		return (0);
748 
749 	for (wantinit = 0; wantinit == 0;) {
750 		isr = CSR_READ_2(sc, STGE_IntStatusAck);
751 		if ((isr & sc->sc_IntEnable) == 0)
752 			break;
753 
754 		/* Host interface errors. */
755 		if (isr & IS_HostError) {
756 			printf("%s: Host interface error\n",
757 			    sc->sc_dev.dv_xname);
758 			wantinit = 1;
759 			continue;
760 		}
761 
762 		/* Receive interrupts. */
763 		if (isr & (IS_RxDMAComplete|IS_RFDListEnd)) {
764 			stge_rxintr(sc);
765 			if (isr & IS_RFDListEnd) {
766 				printf("%s: receive ring overflow\n",
767 				    sc->sc_dev.dv_xname);
768 				/*
769 				 * XXX Should try to recover from this
770 				 * XXX more gracefully.
771 				 */
772 				wantinit = 1;
773 			}
774 		}
775 
776 		/* Transmit interrupts. */
777 		if (isr & (IS_TxDMAComplete|IS_TxComplete))
778 			stge_txintr(sc);
779 
780 		/* Statistics overflow. */
781 		if (isr & IS_UpdateStats)
782 			stge_stats_update(sc);
783 
784 		/* Transmission errors. */
785 		if (isr & IS_TxComplete) {
786 			for (;;) {
787 				txstat = CSR_READ_4(sc, STGE_TxStatus);
788 				if ((txstat & TS_TxComplete) == 0)
789 					break;
790 				if (txstat & TS_TxUnderrun) {
791 					sc->sc_txthresh++;
792 					if (sc->sc_txthresh > 0x0fff)
793 						sc->sc_txthresh = 0x0fff;
794 					printf("%s: transmit underrun, new "
795 					    "threshold: %d bytes\n",
796 					    sc->sc_dev.dv_xname,
797 					    sc->sc_txthresh << 5);
798 				}
799 				if (txstat & TS_MaxCollisions)
800 					printf("%s: excessive collisions\n",
801 					    sc->sc_dev.dv_xname);
802 			}
803 			wantinit = 1;
804 		}
805 
806 	}
807 
808 	if (wantinit)
809 		stge_init(ifp);
810 
811 	CSR_WRITE_2(sc, STGE_IntEnable, sc->sc_IntEnable);
812 
813 	/* Try to get more packets going. */
814 	stge_start(ifp);
815 
816 	return (1);
817 }
818 
819 /*
820  * stge_txintr:
821  *
822  *	Helper; handle transmit interrupts.
823  */
824 void
825 stge_txintr(struct stge_softc *sc)
826 {
827 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
828 	struct stge_descsoft *ds;
829 	uint64_t control;
830 	int i;
831 
832 	ifp->if_flags &= ~IFF_OACTIVE;
833 
834 	/*
835 	 * Go through our Tx list and free mbufs for those
836 	 * frames which have been transmitted.
837 	 */
838 	for (i = sc->sc_txdirty; sc->sc_txpending != 0;
839 	     i = STGE_NEXTTX(i), sc->sc_txpending--) {
840 		ds = &sc->sc_txsoft[i];
841 
842 		STGE_CDTXSYNC(sc, i,
843 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
844 
845 		control = letoh64(sc->sc_txdescs[i].tfd_control);
846 		if ((control & TFD_TFDDone) == 0)
847 			break;
848 
849 		bus_dmamap_sync(sc->sc_dmat, ds->ds_dmamap,
850 		    0, ds->ds_dmamap->dm_mapsize, BUS_DMASYNC_POSTWRITE);
851 		bus_dmamap_unload(sc->sc_dmat, ds->ds_dmamap);
852 		m_freem(ds->ds_mbuf);
853 		ds->ds_mbuf = NULL;
854 	}
855 
856 	/* Update the dirty transmit buffer pointer. */
857 	sc->sc_txdirty = i;
858 
859 	/*
860 	 * If there are no more pending transmissions, cancel the watchdog
861 	 * timer.
862 	 */
863 	if (sc->sc_txpending == 0)
864 		ifp->if_timer = 0;
865 }
866 
867 /*
868  * stge_rxintr:
869  *
870  *	Helper; handle receive interrupts.
871  */
872 void
873 stge_rxintr(struct stge_softc *sc)
874 {
875 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
876 	struct stge_descsoft *ds;
877 	struct mbuf *m, *tailm;
878 	uint64_t status;
879 	int i, len;
880 
881 	for (i = sc->sc_rxptr;; i = STGE_NEXTRX(i)) {
882 		ds = &sc->sc_rxsoft[i];
883 
884 		STGE_CDRXSYNC(sc, i,
885 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
886 
887 		status = letoh64(sc->sc_rxdescs[i].rfd_status);
888 
889 		if ((status & RFD_RFDDone) == 0)
890 			break;
891 
892 		if (__predict_false(sc->sc_rxdiscard)) {
893 			STGE_INIT_RXDESC(sc, i);
894 			if (status & RFD_FrameEnd) {
895 				/* Reset our state. */
896 				sc->sc_rxdiscard = 0;
897 			}
898 			continue;
899 		}
900 
901 		bus_dmamap_sync(sc->sc_dmat, ds->ds_dmamap, 0,
902 		    ds->ds_dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);
903 
904 		m = ds->ds_mbuf;
905 
906 		/*
907 		 * Add a new receive buffer to the ring.
908 		 */
909 		if (stge_add_rxbuf(sc, i) != 0) {
910 			/*
911 			 * Failed, throw away what we've done so
912 			 * far, and discard the rest of the packet.
913 			 */
914 			ifp->if_ierrors++;
915 			bus_dmamap_sync(sc->sc_dmat, ds->ds_dmamap, 0,
916 			    ds->ds_dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);
917 			STGE_INIT_RXDESC(sc, i);
918 			if ((status & RFD_FrameEnd) == 0)
919 				sc->sc_rxdiscard = 1;
920 			if (sc->sc_rxhead != NULL)
921 				m_freem(sc->sc_rxhead);
922 			STGE_RXCHAIN_RESET(sc);
923 			continue;
924 		}
925 
926 #ifdef DIAGNOSTIC
927 		if (status & RFD_FrameStart) {
928 			KASSERT(sc->sc_rxhead == NULL);
929 			KASSERT(sc->sc_rxtailp == &sc->sc_rxhead);
930 		}
931 #endif
932 
933 		STGE_RXCHAIN_LINK(sc, m);
934 
935 		/*
936 		 * If this is not the end of the packet, keep
937 		 * looking.
938 		 */
939 		if ((status & RFD_FrameEnd) == 0) {
940 			sc->sc_rxlen += m->m_len;
941 			continue;
942 		}
943 
944 		/*
945 		 * Okay, we have the entire packet now...
946 		 */
947 		*sc->sc_rxtailp = NULL;
948 		m = sc->sc_rxhead;
949 		tailm = sc->sc_rxtail;
950 
951 		STGE_RXCHAIN_RESET(sc);
952 
953 		/*
954 		 * If the packet had an error, drop it.  Note we
955 		 * count the error later in the periodic stats update.
956 		 */
957 		if (status & (RFD_RxFIFOOverrun | RFD_RxRuntFrame |
958 			      RFD_RxAlignmentError | RFD_RxFCSError |
959 			      RFD_RxLengthError)) {
960 			m_freem(m);
961 			continue;
962 		}
963 
964 		/*
965 		 * No errors.
966 		 *
967 		 * Note we have configured the chip to not include
968 		 * the CRC at the end of the packet.
969 		 */
970 		len = RFD_RxDMAFrameLen(status);
971 		tailm->m_len = len - sc->sc_rxlen;
972 
973 		/*
974 		 * If the packet is small enough to fit in a
975 		 * single header mbuf, allocate one and copy
976 		 * the data into it.  This greatly reduces
977 		 * memory consumption when we receive lots
978 		 * of small packets.
979 		 */
980 		if (stge_copy_small != 0 && len <= (MHLEN - 2)) {
981 			struct mbuf *nm;
982 			MGETHDR(nm, M_DONTWAIT, MT_DATA);
983 			if (nm == NULL) {
984 				ifp->if_ierrors++;
985 				m_freem(m);
986 				continue;
987 			}
988 			nm->m_data += 2;
989 			nm->m_pkthdr.len = nm->m_len = len;
990 			m_copydata(m, 0, len, mtod(nm, caddr_t));
991 			m_freem(m);
992 			m = nm;
993 		}
994 
995 		/*
996 		 * Set the incoming checksum information for the packet.
997 		 */
998 		if ((status & RFD_IPDetected) &&
999 		    (!(status & RFD_IPError)))
1000 			m->m_pkthdr.csum_flags |= M_IPV4_CSUM_IN_OK;
1001 		if ((status & RFD_TCPDetected) &&
1002 		    (!(status & RFD_TCPError)))
1003 			m->m_pkthdr.csum_flags |= M_TCP_CSUM_IN_OK;
1004 		else if ((status & RFD_UDPDetected) &&
1005 		    (!(status & RFD_UDPError)))
1006 			m->m_pkthdr.csum_flags |= M_UDP_CSUM_IN_OK;
1007 
1008 #if NVLAN > 0
1009 		/* Check for VLAN tagged packets. */
1010 		if (status & RFD_VLANDetected) {
1011 			m->m_pkthdr.ether_vtag = RFD_TCI(status);
1012 			m->m_flags |= M_VLANTAG;
1013 		}
1014 #endif
1015 
1016 		m->m_pkthdr.rcvif = ifp;
1017 		m->m_pkthdr.len = len;
1018 
1019 #if NBPFILTER > 0
1020 		/*
1021 		 * Pass this up to any BPF listeners, but only
1022 		 * pass if up the stack if it's for us.
1023 		 */
1024 		if (ifp->if_bpf)
1025 			bpf_mtap_ether(ifp->if_bpf, m, BPF_DIRECTION_IN);
1026 #endif /* NBPFILTER > 0 */
1027 
1028 		/* Pass it on. */
1029 		ether_input_mbuf(ifp, m);
1030 	}
1031 
1032 	/* Update the receive pointer. */
1033 	sc->sc_rxptr = i;
1034 }
1035 
1036 /*
1037  * stge_tick:
1038  *
1039  *	One second timer, used to tick the MII.
1040  */
1041 void
1042 stge_tick(void *arg)
1043 {
1044 	struct stge_softc *sc = arg;
1045 	int s;
1046 
1047 	s = splnet();
1048 	mii_tick(&sc->sc_mii);
1049 	stge_stats_update(sc);
1050 	splx(s);
1051 
1052 	timeout_add_sec(&sc->sc_timeout, 1);
1053 }
1054 
1055 /*
1056  * stge_stats_update:
1057  *
1058  *	Read the TC9021 statistics counters.
1059  */
1060 void
1061 stge_stats_update(struct stge_softc *sc)
1062 {
1063 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1064 
1065 	(void) CSR_READ_4(sc, STGE_OctetRcvOk);
1066 
1067 	ifp->if_ipackets +=
1068 	    CSR_READ_4(sc, STGE_FramesRcvdOk);
1069 
1070 	ifp->if_ierrors +=
1071 	    (u_int) CSR_READ_2(sc, STGE_FramesLostRxErrors);
1072 
1073 	(void) CSR_READ_4(sc, STGE_OctetXmtdOk);
1074 
1075 	ifp->if_opackets +=
1076 	    CSR_READ_4(sc, STGE_FramesXmtdOk);
1077 
1078 	ifp->if_collisions +=
1079 	    CSR_READ_4(sc, STGE_LateCollisions) +
1080 	    CSR_READ_4(sc, STGE_MultiColFrames) +
1081 	    CSR_READ_4(sc, STGE_SingleColFrames);
1082 
1083 	ifp->if_oerrors +=
1084 	    (u_int) CSR_READ_2(sc, STGE_FramesAbortXSColls) +
1085 	    (u_int) CSR_READ_2(sc, STGE_FramesWEXDeferal);
1086 }
1087 
1088 /*
1089  * stge_reset:
1090  *
1091  *	Perform a soft reset on the TC9021.
1092  */
1093 void
1094 stge_reset(struct stge_softc *sc)
1095 {
1096 	uint32_t ac;
1097 	int i;
1098 
1099 	ac = CSR_READ_4(sc, STGE_AsicCtrl);
1100 
1101 	/*
1102 	 * Only assert RstOut if we're fiber.  We need GMII clocks
1103 	 * to be present in order for the reset to complete on fiber
1104 	 * cards.
1105 	 */
1106 	CSR_WRITE_4(sc, STGE_AsicCtrl,
1107 	    ac | AC_GlobalReset | AC_RxReset | AC_TxReset |
1108 	    AC_DMA | AC_FIFO | AC_Network | AC_Host | AC_AutoInit |
1109 	    (sc->sc_usefiber ? AC_RstOut : 0));
1110 
1111 	delay(50000);
1112 
1113 	for (i = 0; i < STGE_TIMEOUT; i++) {
1114 		delay(5000);
1115 		if ((CSR_READ_4(sc, STGE_AsicCtrl) & AC_ResetBusy) == 0)
1116 			break;
1117 	}
1118 
1119 	if (i == STGE_TIMEOUT)
1120 		printf("%s: reset failed to complete\n", sc->sc_dev.dv_xname);
1121 
1122 	delay(1000);
1123 }
1124 
1125 /*
1126  * stge_init:		[ ifnet interface function ]
1127  *
1128  *	Initialize the interface.  Must be called at splnet().
1129  */
1130 int
1131 stge_init(struct ifnet *ifp)
1132 {
1133 	struct stge_softc *sc = ifp->if_softc;
1134 	struct stge_descsoft *ds;
1135 	int i, error = 0;
1136 
1137 	/*
1138 	 * Cancel any pending I/O.
1139 	 */
1140 	stge_stop(ifp, 0);
1141 
1142 	/*
1143 	 * Reset the chip to a known state.
1144 	 */
1145 	stge_reset(sc);
1146 
1147 	/*
1148 	 * Initialize the transmit descriptor ring.
1149 	 */
1150 	memset(sc->sc_txdescs, 0, sizeof(sc->sc_txdescs));
1151 	for (i = 0; i < STGE_NTXDESC; i++) {
1152 		sc->sc_txdescs[i].tfd_next = htole64(
1153 		    STGE_CDTXADDR(sc, STGE_NEXTTX(i)));
1154 		sc->sc_txdescs[i].tfd_control = htole64(TFD_TFDDone);
1155 	}
1156 	sc->sc_txpending = 0;
1157 	sc->sc_txdirty = 0;
1158 	sc->sc_txlast = STGE_NTXDESC - 1;
1159 
1160 	/*
1161 	 * Initialize the receive descriptor and receive job
1162 	 * descriptor rings.
1163 	 */
1164 	for (i = 0; i < STGE_NRXDESC; i++) {
1165 		ds = &sc->sc_rxsoft[i];
1166 		if (ds->ds_mbuf == NULL) {
1167 			if ((error = stge_add_rxbuf(sc, i)) != 0) {
1168 				printf("%s: unable to allocate or map rx "
1169 				    "buffer %d, error = %d\n",
1170 				    sc->sc_dev.dv_xname, i, error);
1171 				/*
1172 				 * XXX Should attempt to run with fewer receive
1173 				 * XXX buffers instead of just failing.
1174 				 */
1175 				stge_rxdrain(sc);
1176 				goto out;
1177 			}
1178 		} else
1179 			STGE_INIT_RXDESC(sc, i);
1180 	}
1181 	sc->sc_rxptr = 0;
1182 	sc->sc_rxdiscard = 0;
1183 	STGE_RXCHAIN_RESET(sc);
1184 
1185 	/* Set the station address. */
1186 	if (sc->sc_stge1023) {
1187 		CSR_WRITE_2(sc, STGE_StationAddress0,
1188 		    sc->sc_arpcom.ac_enaddr[0] | sc->sc_arpcom.ac_enaddr[1] << 8);
1189 		CSR_WRITE_2(sc, STGE_StationAddress1,
1190 		    sc->sc_arpcom.ac_enaddr[2] | sc->sc_arpcom.ac_enaddr[3] << 8);
1191 		CSR_WRITE_2(sc, STGE_StationAddress2,
1192 		    sc->sc_arpcom.ac_enaddr[4] | sc->sc_arpcom.ac_enaddr[5] << 8);
1193 	} else {
1194 		for (i = 0; i < ETHER_ADDR_LEN; i++)
1195 			CSR_WRITE_1(sc, STGE_StationAddress0 + i,
1196 			    sc->sc_arpcom.ac_enaddr[i]);
1197 	}
1198 
1199 	/*
1200 	 * Set the statistics masks.  Disable all the RMON stats,
1201 	 * and disable selected stats in the non-RMON stats registers.
1202 	 */
1203 	CSR_WRITE_4(sc, STGE_RMONStatisticsMask, 0xffffffff);
1204 	CSR_WRITE_4(sc, STGE_StatisticsMask,
1205 	    (1U << 1) | (1U << 2) | (1U << 3) | (1U << 4) | (1U << 5) |
1206 	    (1U << 6) | (1U << 7) | (1U << 8) | (1U << 9) | (1U << 10) |
1207 	    (1U << 13) | (1U << 14) | (1U << 15) | (1U << 19) | (1U << 20) |
1208 	    (1U << 21));
1209 
1210 	/* Program promiscuous mode and multicast filters. */
1211 	stge_iff(sc);
1212 
1213 	/*
1214 	 * Give the transmit and receive ring to the chip.
1215 	 */
1216 	CSR_WRITE_4(sc, STGE_TFDListPtrHi, 0); /* NOTE: 32-bit DMA */
1217 	CSR_WRITE_4(sc, STGE_TFDListPtrLo,
1218 	    STGE_CDTXADDR(sc, sc->sc_txdirty));
1219 
1220 	CSR_WRITE_4(sc, STGE_RFDListPtrHi, 0); /* NOTE: 32-bit DMA */
1221 	CSR_WRITE_4(sc, STGE_RFDListPtrLo,
1222 	    STGE_CDRXADDR(sc, sc->sc_rxptr));
1223 
1224 	/*
1225 	 * Initialize the Tx auto-poll period.  It's OK to make this number
1226 	 * large (255 is the max, but we use 127) -- we explicitly kick the
1227 	 * transmit engine when there's actually a packet.
1228 	 */
1229 	CSR_WRITE_1(sc, STGE_TxDMAPollPeriod, 127);
1230 
1231 	/* ..and the Rx auto-poll period. */
1232 	CSR_WRITE_1(sc, STGE_RxDMAPollPeriod, 64);
1233 
1234 	/* Initialize the Tx start threshold. */
1235 	CSR_WRITE_2(sc, STGE_TxStartThresh, sc->sc_txthresh);
1236 
1237 	/* RX DMA thresholds, from linux */
1238 	CSR_WRITE_1(sc, STGE_RxDMABurstThresh, 0x30);
1239 	CSR_WRITE_1(sc, STGE_RxDMAUrgentThresh, 0x30);
1240 
1241 	/* Rx early threhold, from Linux */
1242 	CSR_WRITE_2(sc, STGE_RxEarlyThresh, 0x7ff);
1243 
1244 	/* Tx DMA thresholds, from Linux */
1245 	CSR_WRITE_1(sc, STGE_TxDMABurstThresh, 0x30);
1246 	CSR_WRITE_1(sc, STGE_TxDMAUrgentThresh, 0x04);
1247 
1248 	/*
1249 	 * Initialize the Rx DMA interrupt control register.  We
1250 	 * request an interrupt after every incoming packet, but
1251 	 * defer it for 32us (64 * 512 ns).  When the number of
1252 	 * interrupts pending reaches 8, we stop deferring the
1253 	 * interrupt, and signal it immediately.
1254 	 */
1255 	CSR_WRITE_4(sc, STGE_RxDMAIntCtrl,
1256 	    RDIC_RxFrameCount(8) | RDIC_RxDMAWaitTime(512));
1257 
1258 	/*
1259 	 * Initialize the interrupt mask.
1260 	 */
1261 	sc->sc_IntEnable = IS_HostError | IS_TxComplete | IS_UpdateStats |
1262 	    IS_TxDMAComplete | IS_RxDMAComplete | IS_RFDListEnd;
1263 	CSR_WRITE_2(sc, STGE_IntStatus, 0xffff);
1264 	CSR_WRITE_2(sc, STGE_IntEnable, sc->sc_IntEnable);
1265 
1266 	/*
1267 	 * Configure the DMA engine.
1268 	 * XXX Should auto-tune TxBurstLimit.
1269 	 */
1270 	CSR_WRITE_4(sc, STGE_DMACtrl, sc->sc_DMACtrl |
1271 	    DMAC_TxBurstLimit(3));
1272 
1273 	/*
1274 	 * Send a PAUSE frame when we reach 29,696 bytes in the Rx
1275 	 * FIFO, and send an un-PAUSE frame when we reach 3056 bytes
1276 	 * in the Rx FIFO.
1277 	 */
1278 	CSR_WRITE_2(sc, STGE_FlowOnTresh, 29696 / 16);
1279 	CSR_WRITE_2(sc, STGE_FlowOffThresh, 3056 / 16);
1280 
1281 	/*
1282 	 * Set the maximum frame size.
1283 	 */
1284 #ifdef STGE_JUMBO
1285 	CSR_WRITE_2(sc, STGE_MaxFrameSize, STGE_JUMBO_FRAMELEN);
1286 #else
1287 	CSR_WRITE_2(sc, STGE_MaxFrameSize, ETHER_MAX_LEN);
1288 #endif
1289 
1290 	/*
1291 	 * Initialize MacCtrl -- do it before setting the media,
1292 	 * as setting the media will actually program the register.
1293 	 *
1294 	 * Note: We have to poke the IFS value before poking
1295 	 * anything else.
1296 	 */
1297 	sc->sc_MACCtrl = MC_IFSSelect(0);
1298 	CSR_WRITE_4(sc, STGE_MACCtrl, sc->sc_MACCtrl);
1299 
1300 	if (ifp->if_capabilities & IFCAP_VLAN_HWTAGGING)
1301 		sc->sc_MACCtrl |= MC_AutoVLANuntagging;
1302 
1303 	sc->sc_MACCtrl |= MC_StatisticsEnable | MC_TxEnable | MC_RxEnable;
1304 
1305 	if (sc->sc_rev >= 6) {		/* >= B.2 */
1306 		/* Multi-frag frame bug work-around. */
1307 		CSR_WRITE_2(sc, STGE_DebugCtrl,
1308 		    CSR_READ_2(sc, STGE_DebugCtrl) | 0x0200);
1309 
1310 		/* Tx Poll Now bug work-around. */
1311 		CSR_WRITE_2(sc, STGE_DebugCtrl,
1312 		    CSR_READ_2(sc, STGE_DebugCtrl) | 0x0010);
1313 
1314 		/* Rx Poll Now bug work-around. */
1315 		CSR_WRITE_2(sc, STGE_DebugCtrl,
1316 		    CSR_READ_2(sc, STGE_DebugCtrl) | 0x0020);
1317 	}
1318 
1319 	/*
1320 	 * Set the current media.
1321 	 */
1322 	mii_mediachg(&sc->sc_mii);
1323 
1324 	/*
1325 	 * Start the one second MII clock.
1326 	 */
1327 	timeout_add_sec(&sc->sc_timeout, 1);
1328 
1329 	/*
1330 	 * ...all done!
1331 	 */
1332 	ifp->if_flags |= IFF_RUNNING;
1333 	ifp->if_flags &= ~IFF_OACTIVE;
1334 
1335  out:
1336 	if (error)
1337 		printf("%s: interface not running\n", sc->sc_dev.dv_xname);
1338 	return (error);
1339 }
1340 
1341 /*
1342  * stge_drain:
1343  *
1344  *	Drain the receive queue.
1345  */
1346 void
1347 stge_rxdrain(struct stge_softc *sc)
1348 {
1349 	struct stge_descsoft *ds;
1350 	int i;
1351 
1352 	for (i = 0; i < STGE_NRXDESC; i++) {
1353 		ds = &sc->sc_rxsoft[i];
1354 		if (ds->ds_mbuf != NULL) {
1355 			bus_dmamap_unload(sc->sc_dmat, ds->ds_dmamap);
1356 			ds->ds_mbuf->m_next = NULL;
1357 			m_freem(ds->ds_mbuf);
1358 			ds->ds_mbuf = NULL;
1359 		}
1360 	}
1361 }
1362 
1363 /*
1364  * stge_stop:		[ ifnet interface function ]
1365  *
1366  *	Stop transmission on the interface.
1367  */
1368 void
1369 stge_stop(struct ifnet *ifp, int disable)
1370 {
1371 	struct stge_softc *sc = ifp->if_softc;
1372 	struct stge_descsoft *ds;
1373 	int i;
1374 
1375 	/*
1376 	 * Stop the one second clock.
1377 	 */
1378 	timeout_del(&sc->sc_timeout);
1379 
1380 	/*
1381 	 * Mark the interface down and cancel the watchdog timer.
1382 	 */
1383 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
1384 	ifp->if_timer = 0;
1385 
1386 	/* Down the MII. */
1387 	mii_down(&sc->sc_mii);
1388 
1389 	/*
1390 	 * Disable interrupts.
1391 	 */
1392 	CSR_WRITE_2(sc, STGE_IntEnable, 0);
1393 
1394 	/*
1395 	 * Stop receiver, transmitter, and stats update.
1396 	 */
1397 	CSR_WRITE_4(sc, STGE_MACCtrl,
1398 	    MC_StatisticsDisable | MC_TxDisable | MC_RxDisable);
1399 
1400 	/*
1401 	 * Stop the transmit and receive DMA.
1402 	 */
1403 	stge_dma_wait(sc);
1404 	CSR_WRITE_4(sc, STGE_TFDListPtrHi, 0);
1405 	CSR_WRITE_4(sc, STGE_TFDListPtrLo, 0);
1406 	CSR_WRITE_4(sc, STGE_RFDListPtrHi, 0);
1407 	CSR_WRITE_4(sc, STGE_RFDListPtrLo, 0);
1408 
1409 	/*
1410 	 * Release any queued transmit buffers.
1411 	 */
1412 	for (i = 0; i < STGE_NTXDESC; i++) {
1413 		ds = &sc->sc_txsoft[i];
1414 		if (ds->ds_mbuf != NULL) {
1415 			bus_dmamap_unload(sc->sc_dmat, ds->ds_dmamap);
1416 			m_freem(ds->ds_mbuf);
1417 			ds->ds_mbuf = NULL;
1418 		}
1419 	}
1420 
1421 	if (disable)
1422 		stge_rxdrain(sc);
1423 }
1424 
1425 static int
1426 stge_eeprom_wait(struct stge_softc *sc)
1427 {
1428 	int i;
1429 
1430 	for (i = 0; i < STGE_TIMEOUT; i++) {
1431 		delay(1000);
1432 		if ((CSR_READ_2(sc, STGE_EepromCtrl) & EC_EepromBusy) == 0)
1433 			return (0);
1434 	}
1435 	return (1);
1436 }
1437 
1438 /*
1439  * stge_read_eeprom:
1440  *
1441  *	Read data from the serial EEPROM.
1442  */
1443 void
1444 stge_read_eeprom(struct stge_softc *sc, int offset, uint16_t *data)
1445 {
1446 
1447 	if (stge_eeprom_wait(sc))
1448 		printf("%s: EEPROM failed to come ready\n",
1449 		    sc->sc_dev.dv_xname);
1450 
1451 	CSR_WRITE_2(sc, STGE_EepromCtrl,
1452 	    EC_EepromAddress(offset) | EC_EepromOpcode(EC_OP_RR));
1453 	if (stge_eeprom_wait(sc))
1454 		printf("%s: EEPROM read timed out\n",
1455 		    sc->sc_dev.dv_xname);
1456 	*data = CSR_READ_2(sc, STGE_EepromData);
1457 }
1458 
1459 /*
1460  * stge_add_rxbuf:
1461  *
1462  *	Add a receive buffer to the indicated descriptor.
1463  */
1464 int
1465 stge_add_rxbuf(struct stge_softc *sc, int idx)
1466 {
1467 	struct stge_descsoft *ds = &sc->sc_rxsoft[idx];
1468 	struct mbuf *m;
1469 	int error;
1470 
1471 	MGETHDR(m, M_DONTWAIT, MT_DATA);
1472 	if (m == NULL)
1473 		return (ENOBUFS);
1474 
1475 	MCLGET(m, M_DONTWAIT);
1476 	if ((m->m_flags & M_EXT) == 0) {
1477 		m_freem(m);
1478 		return (ENOBUFS);
1479 	}
1480 
1481 	m->m_data = m->m_ext.ext_buf + 2;
1482 	m->m_len = MCLBYTES - 2;
1483 
1484 	if (ds->ds_mbuf != NULL)
1485 		bus_dmamap_unload(sc->sc_dmat, ds->ds_dmamap);
1486 
1487 	ds->ds_mbuf = m;
1488 
1489 	error = bus_dmamap_load(sc->sc_dmat, ds->ds_dmamap,
1490 	    m->m_ext.ext_buf, m->m_ext.ext_size, NULL, BUS_DMA_NOWAIT);
1491 	if (error) {
1492 		printf("%s: can't load rx DMA map %d, error = %d\n",
1493 		    sc->sc_dev.dv_xname, idx, error);
1494 		panic("stge_add_rxbuf");	/* XXX */
1495 	}
1496 
1497 	bus_dmamap_sync(sc->sc_dmat, ds->ds_dmamap, 0,
1498 	    ds->ds_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
1499 
1500 	STGE_INIT_RXDESC(sc, idx);
1501 
1502 	return (0);
1503 }
1504 
1505 /*
1506  * stge_iff:
1507  *
1508  *	Set up the receive filter.
1509  */
1510 void
1511 stge_iff(struct stge_softc *sc)
1512 {
1513 	struct arpcom *ac = &sc->sc_arpcom;
1514 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1515 	struct ether_multi *enm;
1516 	struct ether_multistep step;
1517 	uint32_t crc;
1518 	uint32_t mchash[2];
1519 
1520 	memset(mchash, 0, sizeof(mchash));
1521 	ifp->if_flags &= ~IFF_ALLMULTI;
1522 
1523 	/*
1524 	 * Always accept broadcast packets.
1525 	 * Always accept frames destined to our station address.
1526 	 */
1527 	sc->sc_ReceiveMode = RM_ReceiveBroadcast | RM_ReceiveUnicast;
1528 
1529 	if (ifp->if_flags & IFF_PROMISC || ac->ac_multirangecnt > 0) {
1530 		ifp->if_flags |= IFF_ALLMULTI;
1531 		if (ifp->if_flags & IFF_PROMISC)
1532 			sc->sc_ReceiveMode |= RM_ReceiveAllFrames;
1533 		else
1534 			sc->sc_ReceiveMode |= RM_ReceiveMulticast;
1535 	} else {
1536 		/*
1537 		 * Set up the multicast address filter by passing all
1538 		 * multicast addresses through a CRC generator, and then
1539 		 * using the low-order 6 bits as an index into the 64 bit
1540 		 * multicast hash table.  The high order bits select the
1541 		 * register, while the rest of the bits select the bit
1542 		 * within the register.
1543 		 */
1544 		sc->sc_ReceiveMode |= RM_ReceiveMulticastHash;
1545 
1546 		ETHER_FIRST_MULTI(step, ac, enm);
1547 		while (enm != NULL) {
1548 			crc = ether_crc32_be(enm->enm_addrlo,
1549 			    ETHER_ADDR_LEN);
1550 
1551 			/* Just want the 6 least significant bits. */
1552 			crc &= 0x3f;
1553 
1554 			/* Set the corresponding bit in the hash table. */
1555 			mchash[crc >> 5] |= 1 << (crc & 0x1f);
1556 
1557 			ETHER_NEXT_MULTI(step, enm);
1558 		}
1559 	}
1560 
1561 	CSR_WRITE_4(sc, STGE_HashTable0, mchash[0]);
1562 	CSR_WRITE_4(sc, STGE_HashTable1, mchash[1]);
1563 	CSR_WRITE_2(sc, STGE_ReceiveMode, sc->sc_ReceiveMode);
1564 }
1565 
1566 /*
1567  * stge_mii_readreg:	[mii interface function]
1568  *
1569  *	Read a PHY register on the MII of the TC9021.
1570  */
1571 int
1572 stge_mii_readreg(struct device *self, int phy, int reg)
1573 {
1574 
1575 	return (mii_bitbang_readreg(self, &stge_mii_bitbang_ops, phy, reg));
1576 }
1577 
1578 /*
1579  * stge_mii_writereg:	[mii interface function]
1580  *
1581  *	Write a PHY register on the MII of the TC9021.
1582  */
1583 void
1584 stge_mii_writereg(struct device *self, int phy, int reg, int val)
1585 {
1586 
1587 	mii_bitbang_writereg(self, &stge_mii_bitbang_ops, phy, reg, val);
1588 }
1589 
1590 /*
1591  * stge_mii_statchg:	[mii interface function]
1592  *
1593  *	Callback from MII layer when media changes.
1594  */
1595 void
1596 stge_mii_statchg(struct device *self)
1597 {
1598 	struct stge_softc *sc = (struct stge_softc *) self;
1599 	struct mii_data *mii = &sc->sc_mii;
1600 
1601 	sc->sc_MACCtrl &= ~(MC_DuplexSelect | MC_RxFlowControlEnable |
1602 	    MC_TxFlowControlEnable);
1603 
1604 	if (((mii->mii_media_active & IFM_GMASK) & IFM_FDX) != 0)
1605 		sc->sc_MACCtrl |= MC_DuplexSelect;
1606 
1607 	if (((mii->mii_media_active & IFM_GMASK) & IFM_ETH_RXPAUSE) != 0)
1608 		sc->sc_MACCtrl |= MC_RxFlowControlEnable;
1609 	if (((mii->mii_media_active & IFM_GMASK) & IFM_ETH_TXPAUSE) != 0)
1610 		sc->sc_MACCtrl |= MC_TxFlowControlEnable;
1611 
1612 	CSR_WRITE_4(sc, STGE_MACCtrl, sc->sc_MACCtrl);
1613 }
1614 
1615 /*
1616  * sste_mii_bitbang_read: [mii bit-bang interface function]
1617  *
1618  *	Read the MII serial port for the MII bit-bang module.
1619  */
1620 uint32_t
1621 stge_mii_bitbang_read(struct device *self)
1622 {
1623 	struct stge_softc *sc = (void *) self;
1624 
1625 	return (CSR_READ_1(sc, STGE_PhyCtrl));
1626 }
1627 
1628 /*
1629  * stge_mii_bitbang_write: [mii big-bang interface function]
1630  *
1631  *	Write the MII serial port for the MII bit-bang module.
1632  */
1633 void
1634 stge_mii_bitbang_write(struct device *self, uint32_t val)
1635 {
1636 	struct stge_softc *sc = (void *) self;
1637 
1638 	CSR_WRITE_1(sc, STGE_PhyCtrl, val | sc->sc_PhyCtrl);
1639 }
1640 
1641 /*
1642  * stge_mediastatus:	[ifmedia interface function]
1643  *
1644  *	Get the current interface media status.
1645  */
1646 void
1647 stge_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
1648 {
1649 	struct stge_softc *sc = ifp->if_softc;
1650 
1651 	mii_pollstat(&sc->sc_mii);
1652 	ifmr->ifm_status = sc->sc_mii.mii_media_status;
1653 	ifmr->ifm_active = sc->sc_mii.mii_media_active;
1654 }
1655 
1656 /*
1657  * stge_mediachange:	[ifmedia interface function]
1658  *
1659  *	Set hardware to newly-selected media.
1660  */
1661 int
1662 stge_mediachange(struct ifnet *ifp)
1663 {
1664 	struct stge_softc *sc = ifp->if_softc;
1665 
1666 	if (ifp->if_flags & IFF_UP)
1667 		mii_mediachg(&sc->sc_mii);
1668 	return (0);
1669 }
1670