xref: /netbsd-src/sys/dev/pci/if_ste.c (revision 3b01aba77a7a698587faaae455bbfe740923c1f5)
1 /*	$NetBSD: if_ste.c,v 1.6 2001/07/23 17:26:50 thorpej Exp $	*/
2 
3 /*-
4  * Copyright (c) 2001 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the NetBSD
21  *	Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Device driver for the Sundance Tech. ST-201 10/100
41  * Ethernet controller.
42  */
43 
44 #include "bpfilter.h"
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/callout.h>
49 #include <sys/mbuf.h>
50 #include <sys/malloc.h>
51 #include <sys/kernel.h>
52 #include <sys/socket.h>
53 #include <sys/ioctl.h>
54 #include <sys/errno.h>
55 #include <sys/device.h>
56 #include <sys/queue.h>
57 
58 #include <uvm/uvm_extern.h>		/* for PAGE_SIZE */
59 
60 #include <net/if.h>
61 #include <net/if_dl.h>
62 #include <net/if_media.h>
63 #include <net/if_ether.h>
64 
65 #if NBPFILTER > 0
66 #include <net/bpf.h>
67 #endif
68 
69 #include <machine/bus.h>
70 #include <machine/intr.h>
71 
72 #include <dev/mii/mii.h>
73 #include <dev/mii/miivar.h>
74 #include <dev/mii/mii_bitbang.h>
75 
76 #include <dev/pci/pcireg.h>
77 #include <dev/pci/pcivar.h>
78 #include <dev/pci/pcidevs.h>
79 
80 #include <dev/pci/if_stereg.h>
81 
82 /*
83  * Transmit descriptor list size.
84  */
85 #define	STE_NTXDESC		256
86 #define	STE_NTXDESC_MASK	(STE_NTXDESC - 1)
87 #define	STE_NEXTTX(x)		(((x) + 1) & STE_NTXDESC_MASK)
88 
89 /*
90  * Receive descriptor list size.
91  */
92 #define	STE_NRXDESC		128
93 #define	STE_NRXDESC_MASK	(STE_NRXDESC - 1)
94 #define	STE_NEXTRX(x)		(((x) + 1) & STE_NRXDESC_MASK)
95 
96 /*
97  * Control structures are DMA'd to the ST-201 chip.  We allocate them in
98  * a single clump that maps to a single DMA segment to make several things
99  * easier.
100  */
101 struct ste_control_data {
102 	/*
103 	 * The transmit descriptors.
104 	 */
105 	struct ste_tfd scd_txdescs[STE_NTXDESC];
106 
107 	/*
108 	 * The receive descriptors.
109 	 */
110 	struct ste_rfd scd_rxdescs[STE_NRXDESC];
111 };
112 
113 #define	STE_CDOFF(x)	offsetof(struct ste_control_data, x)
114 #define	STE_CDTXOFF(x)	STE_CDOFF(scd_txdescs[(x)])
115 #define	STE_CDRXOFF(x)	STE_CDOFF(scd_rxdescs[(x)])
116 
117 /*
118  * Software state for transmit and receive jobs.
119  */
120 struct ste_descsoft {
121 	struct mbuf *ds_mbuf;		/* head of our mbuf chain */
122 	bus_dmamap_t ds_dmamap;		/* our DMA map */
123 };
124 
125 /*
126  * Software state per device.
127  */
128 struct ste_softc {
129 	struct device sc_dev;		/* generic device information */
130 	bus_space_tag_t sc_st;		/* bus space tag */
131 	bus_space_handle_t sc_sh;	/* bus space handle */
132 	bus_dma_tag_t sc_dmat;		/* bus DMA tag */
133 	struct ethercom sc_ethercom;	/* ethernet common data */
134 	void *sc_sdhook;		/* shutdown hook */
135 
136 	void *sc_ih;			/* interrupt cookie */
137 
138 	struct mii_data sc_mii;		/* MII/media information */
139 
140 	struct callout sc_tick_ch;	/* tick callout */
141 
142 	bus_dmamap_t sc_cddmamap;	/* control data DMA map */
143 #define	sc_cddma	sc_cddmamap->dm_segs[0].ds_addr
144 
145 	/*
146 	 * Software state for transmit and receive descriptors.
147 	 */
148 	struct ste_descsoft sc_txsoft[STE_NTXDESC];
149 	struct ste_descsoft sc_rxsoft[STE_NRXDESC];
150 
151 	/*
152 	 * Control data structures.
153 	 */
154 	struct ste_control_data *sc_control_data;
155 #define	sc_txdescs	sc_control_data->scd_txdescs
156 #define	sc_rxdescs	sc_control_data->scd_rxdescs
157 
158 	int	sc_txpending;		/* number of Tx requests pending */
159 	int	sc_txdirty;		/* first dirty Tx descriptor */
160 	int	sc_txlast;		/* last used Tx descriptor */
161 
162 	int	sc_rxptr;		/* next ready Rx descriptor/descsoft */
163 
164 	int	sc_txthresh;		/* Tx threshold */
165 	uint32_t sc_DMACtrl;		/* prototype DMACtrl register */
166 	uint16_t sc_IntEnable;		/* prototype IntEnable register */
167 	uint16_t sc_MacCtrl0;		/* prototype MacCtrl0 register */
168 	uint8_t	sc_ReceiveMode;		/* prototype ReceiveMode register */
169 };
170 
171 #define	STE_CDTXADDR(sc, x)	((sc)->sc_cddma + STE_CDTXOFF((x)))
172 #define	STE_CDRXADDR(sc, x)	((sc)->sc_cddma + STE_CDRXOFF((x)))
173 
174 #define	STE_CDTXSYNC(sc, x, ops)					\
175 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
176 	    STE_CDTXOFF((x)), sizeof(struct ste_tfd), (ops))
177 
178 #define	STE_CDRXSYNC(sc, x, ops)					\
179 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
180 	    STE_CDRXOFF((x)), sizeof(struct ste_rfd), (ops))
181 
182 #define	STE_INIT_RXDESC(sc, x)						\
183 do {									\
184 	struct ste_descsoft *__ds = &(sc)->sc_rxsoft[(x)];		\
185 	struct ste_rfd *__rfd = &(sc)->sc_rxdescs[(x)];			\
186 	struct mbuf *__m = __ds->ds_mbuf;				\
187 									\
188 	/*								\
189 	 * Note: We scoot the packet forward 2 bytes in the buffer	\
190 	 * so that the payload after the Ethernet header is aligned	\
191 	 * to a 4-byte boundary.					\
192 	 */								\
193 	__m->m_data = __m->m_ext.ext_buf + 2;				\
194 	__rfd->rfd_frag.frag_addr =					\
195 	    htole32(__ds->ds_dmamap->dm_segs[0].ds_addr + 2);		\
196 	__rfd->rfd_frag.frag_len = htole32((MCLBYTES - 2) | FRAG_LAST);	\
197 	__rfd->rfd_next = htole32(STE_CDRXADDR((sc), STE_NEXTRX((x))));	\
198 	__rfd->rfd_status = 0;						\
199 	STE_CDRXSYNC((sc), (x), BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE); \
200 } while (/*CONSTCOND*/0)
201 
202 #define STE_TIMEOUT 1000
203 
204 void	ste_start(struct ifnet *);
205 void	ste_watchdog(struct ifnet *);
206 int	ste_ioctl(struct ifnet *, u_long, caddr_t);
207 int	ste_init(struct ifnet *);
208 void	ste_stop(struct ifnet *, int);
209 
210 void	ste_shutdown(void *);
211 
212 void	ste_reset(struct ste_softc *);
213 void	ste_rxdrain(struct ste_softc *);
214 int	ste_add_rxbuf(struct ste_softc *, int);
215 void	ste_read_eeprom(struct ste_softc *, int, uint16_t *);
216 void	ste_tick(void *);
217 
218 void	ste_stats_update(struct ste_softc *);
219 
220 void	ste_set_filter(struct ste_softc *);
221 
222 int	ste_intr(void *);
223 void	ste_txintr(struct ste_softc *);
224 void	ste_rxintr(struct ste_softc *);
225 
226 int	ste_mii_readreg(struct device *, int, int);
227 void	ste_mii_writereg(struct device *, int, int, int);
228 void	ste_mii_statchg(struct device *);
229 
230 int	ste_mediachange(struct ifnet *);
231 void	ste_mediastatus(struct ifnet *, struct ifmediareq *);
232 
233 int	ste_match(struct device *, struct cfdata *, void *);
234 void	ste_attach(struct device *, struct device *, void *);
235 
236 int	ste_copy_small = 0;
237 
238 struct cfattach ste_ca = {
239 	sizeof(struct ste_softc), ste_match, ste_attach,
240 };
241 
242 uint32_t ste_mii_bitbang_read(struct device *);
243 void	ste_mii_bitbang_write(struct device *, uint32_t);
244 
245 const struct mii_bitbang_ops ste_mii_bitbang_ops = {
246 	ste_mii_bitbang_read,
247 	ste_mii_bitbang_write,
248 	{
249 		PC_MgmtData,		/* MII_BIT_MDO */
250 		PC_MgmtData,		/* MII_BIT_MDI */
251 		PC_MgmtClk,		/* MII_BIT_MDC */
252 		PC_MgmtDir,		/* MII_BIT_DIR_HOST_PHY */
253 		0,			/* MII_BIT_DIR_PHY_HOST */
254 	}
255 };
256 
257 /*
258  * Devices supported by this driver.
259  */
260 const struct ste_product {
261 	pci_vendor_id_t		ste_vendor;
262 	pci_product_id_t	ste_product;
263 	const char		*ste_name;
264 } ste_products[] = {
265 	{ PCI_VENDOR_SUNDANCETI,	PCI_PRODUCT_SUNDANCETI_ST201,
266 	  "Sundance ST-201 10/100 Ethernet" },
267 
268 	{ PCI_VENDOR_DLINK,		PCI_PRODUCT_DLINK_DL1002,
269 	  "D-Link DL-1002 10/100 Ethernet" },
270 
271 	{ 0,				0,
272 	  NULL },
273 };
274 
275 static const struct ste_product *
276 ste_lookup(const struct pci_attach_args *pa)
277 {
278 	const struct ste_product *sp;
279 
280 	for (sp = ste_products; sp->ste_name != NULL; sp++) {
281 		if (PCI_VENDOR(pa->pa_id) == sp->ste_vendor &&
282 		    PCI_PRODUCT(pa->pa_id) == sp->ste_product)
283 			return (sp);
284 	}
285 	return (NULL);
286 }
287 
288 int
289 ste_match(struct device *parent, struct cfdata *cf, void *aux)
290 {
291 	struct pci_attach_args *pa = aux;
292 
293 	if (ste_lookup(pa) != NULL)
294 		return (1);
295 
296 	return (0);
297 }
298 
299 void
300 ste_attach(struct device *parent, struct device *self, void *aux)
301 {
302 	struct ste_softc *sc = (struct ste_softc *) self;
303 	struct pci_attach_args *pa = aux;
304 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
305 	pci_chipset_tag_t pc = pa->pa_pc;
306 	pci_intr_handle_t ih;
307 	const char *intrstr = NULL;
308 	bus_space_tag_t iot, memt;
309 	bus_space_handle_t ioh, memh;
310 	bus_dma_segment_t seg;
311 	int ioh_valid, memh_valid;
312 	int i, rseg, error;
313 	const struct ste_product *sp;
314 	pcireg_t pmode;
315 	uint8_t enaddr[ETHER_ADDR_LEN];
316 	uint16_t myea[ETHER_ADDR_LEN / 2];
317 	int pmreg;
318 
319 	callout_init(&sc->sc_tick_ch);
320 
321 	sp = ste_lookup(pa);
322 	if (sp == NULL) {
323 		printf("\n");
324 		panic("ste_attach: impossible");
325 	}
326 
327 	printf(": %s\n", sp->ste_name);
328 
329 	/*
330 	 * Map the device.
331 	 */
332 	ioh_valid = (pci_mapreg_map(pa, STE_PCI_IOBA,
333 	    PCI_MAPREG_TYPE_IO, 0,
334 	    &iot, &ioh, NULL, NULL) == 0);
335 	memh_valid = (pci_mapreg_map(pa, STE_PCI_MMBA,
336 	    PCI_MAPREG_TYPE_MEM|PCI_MAPREG_MEM_TYPE_32BIT, 0,
337 	    &memt, &memh, NULL, NULL) == 0);
338 
339 	if (memh_valid) {
340 		sc->sc_st = memt;
341 		sc->sc_sh = memh;
342 	} else if (ioh_valid) {
343 		sc->sc_st = iot;
344 		sc->sc_sh = ioh;
345 	} else {
346 		printf("%s: unable to map device registers\n",
347 		    sc->sc_dev.dv_xname);
348 		return;
349 	}
350 
351 	sc->sc_dmat = pa->pa_dmat;
352 
353 	/* Enable bus mastering. */
354 	pci_conf_write(pc, pa->pa_tag, PCI_COMMAND_STATUS_REG,
355 	    pci_conf_read(pc, pa->pa_tag, PCI_COMMAND_STATUS_REG) |
356 	    PCI_COMMAND_MASTER_ENABLE);
357 
358 	/* Get it out of power save mode if needed. */
359 	if (pci_get_capability(pc, pa->pa_tag, PCI_CAP_PWRMGMT, &pmreg, 0)) {
360 		pmode = pci_conf_read(pc, pa->pa_tag, pmreg + 4) & 0x3;
361 		if (pmode == 3) {
362 			/*
363 			 * The card has lost all configuration data in
364 			 * this state, so punt.
365 			 */
366 			printf("%s: unable to wake up from power state D3\n",
367 			    sc->sc_dev.dv_xname);
368 			return;
369 		}
370 		if (pmode != 0) {
371 			printf("%s: waking up from power state D%d\n",
372 			    sc->sc_dev.dv_xname, pmode);
373 			pci_conf_write(pc, pa->pa_tag, pmreg + 4, 0);
374 		}
375 	}
376 
377 	/*
378 	 * Map and establish our interrupt.
379 	 */
380 	if (pci_intr_map(pa, &ih)) {
381 		printf("%s: unable to map interrupt\n", sc->sc_dev.dv_xname);
382 		return;
383 	}
384 	intrstr = pci_intr_string(pc, ih);
385 	sc->sc_ih = pci_intr_establish(pc, ih, IPL_NET, ste_intr, sc);
386 	if (sc->sc_ih == NULL) {
387 		printf("%s: unable to establish interrupt",
388 		    sc->sc_dev.dv_xname);
389 		if (intrstr != NULL)
390 			printf(" at %s", intrstr);
391 		printf("\n");
392 		return;
393 	}
394 	printf("%s: interrupting at %s\n", sc->sc_dev.dv_xname, intrstr);
395 
396 	/*
397 	 * Allocate the control data structures, and create and load the
398 	 * DMA map for it.
399 	 */
400 	if ((error = bus_dmamem_alloc(sc->sc_dmat,
401 	    sizeof(struct ste_control_data), PAGE_SIZE, 0, &seg, 1, &rseg,
402 	    0)) != 0) {
403 		printf("%s: unable to allocate control data, error = %d\n",
404 		    sc->sc_dev.dv_xname, error);
405 		goto fail_0;
406 	}
407 
408 	if ((error = bus_dmamem_map(sc->sc_dmat, &seg, rseg,
409 	    sizeof(struct ste_control_data), (caddr_t *)&sc->sc_control_data,
410 	    BUS_DMA_COHERENT)) != 0) {
411 		printf("%s: unable to map control data, error = %d\n",
412 		    sc->sc_dev.dv_xname, error);
413 		goto fail_1;
414 	}
415 
416 	if ((error = bus_dmamap_create(sc->sc_dmat,
417 	    sizeof(struct ste_control_data), 1,
418 	    sizeof(struct ste_control_data), 0, 0, &sc->sc_cddmamap)) != 0) {
419 		printf("%s: unable to create control data DMA map, "
420 		    "error = %d\n", sc->sc_dev.dv_xname, error);
421 		goto fail_2;
422 	}
423 
424 	if ((error = bus_dmamap_load(sc->sc_dmat, sc->sc_cddmamap,
425 	    sc->sc_control_data, sizeof(struct ste_control_data), NULL,
426 	    0)) != 0) {
427 		printf("%s: unable to load control data DMA map, error = %d\n",
428 		    sc->sc_dev.dv_xname, error);
429 		goto fail_3;
430 	}
431 
432 	/*
433 	 * Create the transmit buffer DMA maps.
434 	 */
435 	for (i = 0; i < STE_NTXDESC; i++) {
436 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES,
437 		    STE_NTXFRAGS, MCLBYTES, 0, 0,
438 		    &sc->sc_txsoft[i].ds_dmamap)) != 0) {
439 			printf("%s: unable to create tx DMA map %d, "
440 			    "error = %d\n", sc->sc_dev.dv_xname, i, error);
441 			goto fail_4;
442 		}
443 	}
444 
445 	/*
446 	 * Create the receive buffer DMA maps.
447 	 */
448 	for (i = 0; i < STE_NRXDESC; i++) {
449 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES, 1,
450 		    MCLBYTES, 0, 0, &sc->sc_rxsoft[i].ds_dmamap)) != 0) {
451 			printf("%s: unable to create rx DMA map %d, "
452 			    "error = %d\n", sc->sc_dev.dv_xname, i, error);
453 			goto fail_5;
454 		}
455 		sc->sc_rxsoft[i].ds_mbuf = NULL;
456 	}
457 
458 	/*
459 	 * Reset the chip to a known state.
460 	 */
461 	ste_reset(sc);
462 
463 	/*
464 	 * Read the Ethernet address from the EEPROM.
465 	 */
466 	for (i = 0; i < 3; i++) {
467 		ste_read_eeprom(sc, STE_EEPROM_StationAddress0 + i, &myea[i]);
468 		myea[i] = le16toh(myea[i]);
469 	}
470 	memcpy(enaddr, myea, sizeof(enaddr));
471 
472 	printf("%s: Ethernet address %s\n", sc->sc_dev.dv_xname,
473 	    ether_sprintf(enaddr));
474 
475 	/*
476 	 * Initialize our media structures and probe the MII.
477 	 */
478 	sc->sc_mii.mii_ifp = ifp;
479 	sc->sc_mii.mii_readreg = ste_mii_readreg;
480 	sc->sc_mii.mii_writereg = ste_mii_writereg;
481 	sc->sc_mii.mii_statchg = ste_mii_statchg;
482 	ifmedia_init(&sc->sc_mii.mii_media, 0, ste_mediachange,
483 	    ste_mediastatus);
484 	mii_attach(&sc->sc_dev, &sc->sc_mii, 0xffffffff, MII_PHY_ANY,
485 	    MII_OFFSET_ANY, 0);
486 	if (LIST_FIRST(&sc->sc_mii.mii_phys) == NULL) {
487 		ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE, 0, NULL);
488 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE);
489 	} else
490 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_AUTO);
491 
492 	ifp = &sc->sc_ethercom.ec_if;
493 	strcpy(ifp->if_xname, sc->sc_dev.dv_xname);
494 	ifp->if_softc = sc;
495 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
496 	ifp->if_ioctl = ste_ioctl;
497 	ifp->if_start = ste_start;
498 	ifp->if_watchdog = ste_watchdog;
499 	ifp->if_init = ste_init;
500 	ifp->if_stop = ste_stop;
501 	IFQ_SET_READY(&ifp->if_snd);
502 
503 	/*
504 	 * Default the transmit threshold to 128 bytes.
505 	 */
506 	sc->sc_txthresh = 128;
507 
508 	/*
509 	 * Disable MWI if the PCI layer tells us to.
510 	 */
511 	sc->sc_DMACtrl = 0;
512 	if ((pa->pa_flags & PCI_FLAGS_MWI_OKAY) == 0)
513 		sc->sc_DMACtrl |= DC_MWIDisable;
514 
515 	/*
516 	 * We can support 802.1Q VLAN-sized frames.
517 	 */
518 	sc->sc_ethercom.ec_capabilities |= ETHERCAP_VLAN_MTU;
519 
520 	/*
521 	 * Attach the interface.
522 	 */
523 	if_attach(ifp);
524 	ether_ifattach(ifp, enaddr);
525 
526 	/*
527 	 * Make sure the interface is shutdown during reboot.
528 	 */
529 	sc->sc_sdhook = shutdownhook_establish(ste_shutdown, sc);
530 	if (sc->sc_sdhook == NULL)
531 		printf("%s: WARNING: unable to establish shutdown hook\n",
532 		    sc->sc_dev.dv_xname);
533 	return;
534 
535 	/*
536 	 * Free any resources we've allocated during the failed attach
537 	 * attempt.  Do this in reverse order and fall through.
538 	 */
539  fail_5:
540 	for (i = 0; i < STE_NRXDESC; i++) {
541 		if (sc->sc_rxsoft[i].ds_dmamap != NULL)
542 			bus_dmamap_destroy(sc->sc_dmat,
543 			    sc->sc_rxsoft[i].ds_dmamap);
544 	}
545  fail_4:
546 	for (i = 0; i < STE_NTXDESC; i++) {
547 		if (sc->sc_txsoft[i].ds_dmamap != NULL)
548 			bus_dmamap_destroy(sc->sc_dmat,
549 			    sc->sc_txsoft[i].ds_dmamap);
550 	}
551 	bus_dmamap_unload(sc->sc_dmat, sc->sc_cddmamap);
552  fail_3:
553 	bus_dmamap_destroy(sc->sc_dmat, sc->sc_cddmamap);
554  fail_2:
555 	bus_dmamem_unmap(sc->sc_dmat, (caddr_t)sc->sc_control_data,
556 	    sizeof(struct ste_control_data));
557  fail_1:
558 	bus_dmamem_free(sc->sc_dmat, &seg, rseg);
559  fail_0:
560 	return;
561 }
562 
563 /*
564  * ste_shutdown:
565  *
566  *	Make sure the interface is stopped at reboot time.
567  */
568 void
569 ste_shutdown(void *arg)
570 {
571 	struct ste_softc *sc = arg;
572 
573 	ste_stop(&sc->sc_ethercom.ec_if, 1);
574 }
575 
576 static void
577 ste_dmahalt_wait(struct ste_softc *sc)
578 {
579 	int i;
580 
581 	for (i = 0; i < STE_TIMEOUT; i++) {
582 		delay(2);
583 		if ((bus_space_read_4(sc->sc_st, sc->sc_sh, STE_DMACtrl) &
584 		     DC_DMAHaltBusy) == 0)
585 			break;
586 	}
587 
588 	if (i == STE_TIMEOUT)
589 		printf("%s: DMA halt timed out\n", sc->sc_dev.dv_xname);
590 }
591 
592 /*
593  * ste_start:		[ifnet interface function]
594  *
595  *	Start packet transmission on the interface.
596  */
597 void
598 ste_start(struct ifnet *ifp)
599 {
600 	struct ste_softc *sc = ifp->if_softc;
601 	struct mbuf *m0, *m;
602 	struct ste_descsoft *ds;
603 	struct ste_tfd *tfd;
604 	bus_dmamap_t dmamap;
605 	int error, olasttx, nexttx, opending, seg, totlen;
606 
607 	if ((ifp->if_flags & (IFF_RUNNING|IFF_OACTIVE)) != IFF_RUNNING)
608 		return;
609 
610 	/*
611 	 * Remember the previous number of pending transmissions
612 	 * and the current last descriptor in the list.
613 	 */
614 	opending = sc->sc_txpending;
615 	olasttx = sc->sc_txlast;
616 
617 	/*
618 	 * Loop through the send queue, setting up transmit descriptors
619 	 * until we drain the queue, or use up all available transmit
620 	 * descriptors.
621 	 */
622 	while (sc->sc_txpending < STE_NTXDESC) {
623 		/*
624 		 * Grab a packet off the queue.
625 		 */
626 		IFQ_POLL(&ifp->if_snd, m0);
627 		if (m0 == NULL)
628 			break;
629 		m = NULL;
630 
631 		/*
632 		 * Get the last and next available transmit descriptor.
633 		 */
634 		nexttx = STE_NEXTTX(sc->sc_txlast);
635 		tfd = &sc->sc_txdescs[nexttx];
636 		ds = &sc->sc_txsoft[nexttx];
637 
638 		dmamap = ds->ds_dmamap;
639 
640 		/*
641 		 * Load the DMA map.  If this fails, the packet either
642 		 * didn't fit in the alloted number of segments, or we
643 		 * were short on resources.  In this case, we'll copy
644 		 * and try again.
645 		 */
646 		if (bus_dmamap_load_mbuf(sc->sc_dmat, dmamap, m0,
647 		    BUS_DMA_WRITE|BUS_DMA_NOWAIT) != 0) {
648 			MGETHDR(m, M_DONTWAIT, MT_DATA);
649 			if (m == NULL) {
650 				printf("%s: unable to allocate Tx mbuf\n",
651 				    sc->sc_dev.dv_xname);
652 				break;
653 			}
654 			if (m0->m_pkthdr.len > MHLEN) {
655 				MCLGET(m, M_DONTWAIT);
656 				if ((m->m_flags & M_EXT) == 0) {
657 					printf("%s: unable to allocate Tx "
658 					    "cluster\n", sc->sc_dev.dv_xname);
659 					m_freem(m);
660 					break;
661 				}
662 			}
663 			m_copydata(m0, 0, m0->m_pkthdr.len, mtod(m, caddr_t));
664 			m->m_pkthdr.len = m->m_len = m0->m_pkthdr.len;
665 			error = bus_dmamap_load_mbuf(sc->sc_dmat, dmamap,
666 			    m, BUS_DMA_WRITE|BUS_DMA_NOWAIT);
667 			if (error) {
668 				printf("%s: unable to load Tx buffer, "
669 				    "error = %d\n", sc->sc_dev.dv_xname, error);
670 				break;
671 			}
672 		}
673 
674 		IFQ_DEQUEUE(&ifp->if_snd, m0);
675 		if (m != NULL) {
676 			m_freem(m0);
677 			m0 = m;
678 		}
679 
680 		/*
681 		 * WE ARE NOW COMMITTED TO TRANSMITTING THE PACKET.
682 		 */
683 
684 		/* Sync the DMA map. */
685 		bus_dmamap_sync(sc->sc_dmat, dmamap, 0, dmamap->dm_mapsize,
686 		    BUS_DMASYNC_PREWRITE);
687 
688 		/* Initialize the fragment list. */
689 		for (totlen = 0, seg = 0; seg < dmamap->dm_nsegs; seg++) {
690 			tfd->tfd_frags[seg].frag_addr =
691 			    htole32(dmamap->dm_segs[seg].ds_addr);
692 			tfd->tfd_frags[seg].frag_len =
693 			    htole32(dmamap->dm_segs[seg].ds_len);
694 			totlen += dmamap->dm_segs[seg].ds_len;
695 		}
696 		tfd->tfd_frags[seg - 1].frag_len |= htole32(FRAG_LAST);
697 
698 		/* Initialize the descriptor. */
699 		tfd->tfd_next = htole32(STE_CDTXADDR(sc, nexttx));
700 		tfd->tfd_control = htole32(TFD_FrameId(nexttx) | (totlen & 3));
701 
702 		/* Sync the descriptor. */
703 		STE_CDTXSYNC(sc, nexttx,
704 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
705 
706 		/*
707 		 * Store a pointer to the packet so we can free it later,
708 		 * and remember what txdirty will be once the packet is
709 		 * done.
710 		 */
711 		ds->ds_mbuf = m0;
712 
713 		/* Advance the tx pointer. */
714 		sc->sc_txpending++;
715 		sc->sc_txlast = nexttx;
716 
717 #if NBPFILTER > 0
718 		/*
719 		 * Pass the packet to any BPF listeners.
720 		 */
721 		if (ifp->if_bpf)
722 			bpf_mtap(ifp->if_bpf, m0);
723 #endif /* NBPFILTER > 0 */
724 	}
725 
726 	if (sc->sc_txpending == STE_NTXDESC) {
727 		/* No more slots left; notify upper layer. */
728 		ifp->if_flags |= IFF_OACTIVE;
729 	}
730 
731 	if (sc->sc_txpending != opending) {
732 		/*
733 		 * We enqueued packets.  If the transmitter was idle,
734 		 * reset the txdirty pointer.
735 		 */
736 		if (opending == 0)
737 			sc->sc_txdirty = STE_NEXTTX(olasttx);
738 
739 		/*
740 		 * Cause a descriptor interrupt to happen on the
741 		 * last packet we enqueued, and also cause the
742 		 * DMA engine to wait after is has finished processing
743 		 * it.
744 		 */
745 		sc->sc_txdescs[sc->sc_txlast].tfd_next = 0;
746 		sc->sc_txdescs[sc->sc_txlast].tfd_control |=
747 		    htole32(TFD_TxDMAIndicate);
748 		STE_CDTXSYNC(sc, sc->sc_txlast,
749 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
750 
751 		/*
752 		 * Link up the new chain of descriptors to the
753 		 * last.
754 		 */
755 		sc->sc_txdescs[olasttx].tfd_next =
756 		    STE_CDTXADDR(sc, STE_NEXTTX(olasttx));
757 		STE_CDTXSYNC(sc, olasttx,
758 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
759 
760 		/*
761 		 * Kick the transmit DMA logic.  Note that since we're
762 		 * using auto-polling, reading the Tx desc pointer will
763 		 * give it the nudge it needs to get going.
764 		 */
765 		if (bus_space_read_4(sc->sc_st, sc->sc_sh,
766 		    STE_TxDMAListPtr) == 0) {
767 			bus_space_write_4(sc->sc_st, sc->sc_sh,
768 			    STE_DMACtrl, DC_TxDMAHalt);
769 			ste_dmahalt_wait(sc);
770 			bus_space_write_4(sc->sc_st, sc->sc_sh,
771 			    STE_TxDMAListPtr,
772 			    STE_CDTXADDR(sc, STE_NEXTTX(olasttx)));
773 			bus_space_write_4(sc->sc_st, sc->sc_sh,
774 			    STE_DMACtrl, DC_TxDMAResume);
775 		}
776 
777 		/* Set a watchdog timer in case the chip flakes out. */
778 		ifp->if_timer = 5;
779 	}
780 }
781 
782 /*
783  * ste_watchdog:	[ifnet interface function]
784  *
785  *	Watchdog timer handler.
786  */
787 void
788 ste_watchdog(struct ifnet *ifp)
789 {
790 	struct ste_softc *sc = ifp->if_softc;
791 
792 	printf("%s: device timeout\n", sc->sc_dev.dv_xname);
793 	ifp->if_oerrors++;
794 
795 	(void) ste_init(ifp);
796 
797 	/* Try to get more packets going. */
798 	ste_start(ifp);
799 }
800 
801 /*
802  * ste_ioctl:		[ifnet interface function]
803  *
804  *	Handle control requests from the operator.
805  */
806 int
807 ste_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
808 {
809 	struct ste_softc *sc = ifp->if_softc;
810 	struct ifreq *ifr = (struct ifreq *)data;
811 	int s, error;
812 
813 	s = splnet();
814 
815 	switch (cmd) {
816 	case SIOCSIFMEDIA:
817 	case SIOCGIFMEDIA:
818 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii.mii_media, cmd);
819 		break;
820 
821 	default:
822 		error = ether_ioctl(ifp, cmd, data);
823 		if (error == ENETRESET) {
824 			/*
825 			 * Multicast list has changed; set the hardware filter
826 			 * accordingly.
827 			 */
828 			ste_set_filter(sc);
829 			error = 0;
830 		}
831 		break;
832 	}
833 
834 	/* Try to get more packets going. */
835 	ste_start(ifp);
836 
837 	splx(s);
838 	return (error);
839 }
840 
841 /*
842  * ste_intr:
843  *
844  *	Interrupt service routine.
845  */
846 int
847 ste_intr(void *arg)
848 {
849 	struct ste_softc *sc = arg;
850 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
851 	uint16_t isr;
852 	uint8_t txstat;
853 	int wantinit;
854 
855 	if ((bus_space_read_2(sc->sc_st, sc->sc_sh, STE_IntStatus) &
856 	     IS_InterruptStatus) == 0)
857 		return (0);
858 
859 	for (wantinit = 0; wantinit == 0;) {
860 		isr = bus_space_read_2(sc->sc_st, sc->sc_sh, STE_IntStatusAck);
861 		if ((isr & sc->sc_IntEnable) == 0)
862 			break;
863 
864 		/* Receive interrupts. */
865 		if (isr & IE_RxDMAComplete)
866 			ste_rxintr(sc);
867 
868 		/* Transmit interrupts. */
869 		if (isr & (IE_TxDMAComplete|IE_TxComplete))
870 			ste_txintr(sc);
871 
872 		/* Statistics overflow. */
873 		if (isr & IE_UpdateStats)
874 			ste_stats_update(sc);
875 
876 		/* Transmission errors. */
877 		if (isr & IE_TxComplete) {
878 			for (;;) {
879 				txstat = bus_space_read_1(sc->sc_st, sc->sc_sh,
880 				    STE_TxStatus);
881 				if ((txstat & TS_TxComplete) == 0)
882 					break;
883 				if (txstat & TS_TxUnderrun) {
884 					sc->sc_txthresh += 32;
885 					if (sc->sc_txthresh > 0x1ffc)
886 						sc->sc_txthresh = 0x1ffc;
887 					printf("%s: transmit underrun, new "
888 					    "threshold: %d bytes\n",
889 					    sc->sc_dev.dv_xname,
890 					    sc->sc_txthresh);
891 				}
892 				if (txstat & TS_TxReleaseError)
893 					printf("%s: Tx FIFO release error\n",
894 					    sc->sc_dev.dv_xname);
895 				if (txstat & TS_MaxCollisions)
896 					printf("%s: excessive collisions\n",
897 					    sc->sc_dev.dv_xname);
898 				bus_space_write_2(sc->sc_st, sc->sc_sh,
899 				    STE_TxStatus, 0);
900 			}
901 			wantinit = 1;
902 		}
903 
904 		/* Host interface errors. */
905 		if (isr & IE_HostError) {
906 			printf("%s: Host interface error\n",
907 			    sc->sc_dev.dv_xname);
908 			wantinit = 1;
909 		}
910 	}
911 
912 	if (wantinit)
913 		ste_init(ifp);
914 
915 	bus_space_write_2(sc->sc_st, sc->sc_sh, STE_IntEnable,
916 	    sc->sc_IntEnable);
917 
918 	/* Try to get more packets going. */
919 	ste_start(ifp);
920 
921 	return (1);
922 }
923 
924 /*
925  * ste_txintr:
926  *
927  *	Helper; handle transmit interrupts.
928  */
929 void
930 ste_txintr(struct ste_softc *sc)
931 {
932 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
933 	struct ste_descsoft *ds;
934 	uint32_t control;
935 	int i;
936 
937 	ifp->if_flags &= ~IFF_OACTIVE;
938 
939 	/*
940 	 * Go through our Tx list and free mbufs for those
941 	 * frames which have been transmitted.
942 	 */
943 	for (i = sc->sc_txdirty; sc->sc_txpending != 0;
944 	     i = STE_NEXTTX(i), sc->sc_txpending--) {
945 		ds = &sc->sc_txsoft[i];
946 
947 		STE_CDTXSYNC(sc, i,
948 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
949 
950 		control = le32toh(sc->sc_txdescs[i].tfd_control);
951 		if ((control & TFD_TxDMAComplete) == 0)
952 			break;
953 
954 		bus_dmamap_sync(sc->sc_dmat, ds->ds_dmamap,
955 		    0, ds->ds_dmamap->dm_mapsize, BUS_DMASYNC_POSTWRITE);
956 		bus_dmamap_unload(sc->sc_dmat, ds->ds_dmamap);
957 		m_freem(ds->ds_mbuf);
958 		ds->ds_mbuf = NULL;
959 	}
960 
961 	/* Update the dirty transmit buffer pointer. */
962 	sc->sc_txdirty = i;
963 
964 	/*
965 	 * If there are no more pending transmissions, cancel the watchdog
966 	 * timer.
967 	 */
968 	if (sc->sc_txpending == 0)
969 		ifp->if_timer = 0;
970 }
971 
972 /*
973  * ste_rxintr:
974  *
975  *	Helper; handle receive interrupts.
976  */
977 void
978 ste_rxintr(struct ste_softc *sc)
979 {
980 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
981 	struct ste_descsoft *ds;
982 	struct mbuf *m;
983 	uint32_t status;
984 	int i, len;
985 
986 	for (i = sc->sc_rxptr;; i = STE_NEXTRX(i)) {
987 		ds = &sc->sc_rxsoft[i];
988 
989 		STE_CDRXSYNC(sc, i, BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
990 
991 		status = le32toh(sc->sc_rxdescs[i].rfd_status);
992 
993 		if ((status & RFD_RxDMAComplete) == 0)
994 			break;
995 
996 		/*
997 		 * If the packet had an error, simply recycle the
998 		 * buffer.  Note, we count the error later in the
999 		 * periodic stats update.
1000 		 */
1001 		if (status & RFD_RxFrameError) {
1002 			STE_INIT_RXDESC(sc, i);
1003 			continue;
1004 		}
1005 
1006 		bus_dmamap_sync(sc->sc_dmat, ds->ds_dmamap, 0,
1007 		    ds->ds_dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);
1008 
1009 		/*
1010 		 * No errors; receive the packet.  Note, we have
1011 		 * configured the chip to not include the CRC at
1012 		 * the end of the packet.
1013 		 */
1014 		len = RFD_RxDMAFrameLen(status);
1015 
1016 		/*
1017 		 * If the packet is small enough to fit in a
1018 		 * single header mbuf, allocate one and copy
1019 		 * the data into it.  This greatly reduces
1020 		 * memory consumption when we receive lots
1021 		 * of small packets.
1022 		 *
1023 		 * Otherwise, we add a new buffer to the receive
1024 		 * chain.  If this fails, we drop the packet and
1025 		 * recycle the old buffer.
1026 		 */
1027 		if (ste_copy_small != 0 && len <= (MHLEN - 2)) {
1028 			MGETHDR(m, M_DONTWAIT, MT_DATA);
1029 			if (m == NULL)
1030 				goto dropit;
1031 			m->m_data += 2;
1032 			memcpy(mtod(m, caddr_t),
1033 			    mtod(ds->ds_mbuf, caddr_t), len);
1034 			STE_INIT_RXDESC(sc, i);
1035 			bus_dmamap_sync(sc->sc_dmat, ds->ds_dmamap, 0,
1036 			    ds->ds_dmamap->dm_mapsize,
1037 			    BUS_DMASYNC_PREREAD);
1038 		} else {
1039 			m = ds->ds_mbuf;
1040 			if (ste_add_rxbuf(sc, i) != 0) {
1041  dropit:
1042 				ifp->if_ierrors++;
1043 				STE_INIT_RXDESC(sc, i);
1044 				bus_dmamap_sync(sc->sc_dmat,
1045 				    ds->ds_dmamap, 0,
1046 				    ds->ds_dmamap->dm_mapsize,
1047 				    BUS_DMASYNC_PREREAD);
1048 				continue;
1049 			}
1050 		}
1051 
1052 		m->m_pkthdr.rcvif = ifp;
1053 		m->m_pkthdr.len = m->m_len = len;
1054 
1055 #if NBPFILTER > 0
1056 		/*
1057 		 * Pass this up to any BPF listeners, but only
1058 		 * pass if up the stack if it's for us.
1059 		 */
1060 		if (ifp->if_bpf)
1061 			bpf_mtap(ifp->if_bpf, m);
1062 #endif /* NBPFILTER > 0 */
1063 
1064 		/* Pass it on. */
1065 		(*ifp->if_input)(ifp, m);
1066 	}
1067 
1068 	/* Update the receive pointer. */
1069 	sc->sc_rxptr = i;
1070 }
1071 
1072 /*
1073  * ste_tick:
1074  *
1075  *	One second timer, used to tick the MII.
1076  */
1077 void
1078 ste_tick(void *arg)
1079 {
1080 	struct ste_softc *sc = arg;
1081 	int s;
1082 
1083 	s = splnet();
1084 	mii_tick(&sc->sc_mii);
1085 	ste_stats_update(sc);
1086 	splx(s);
1087 
1088 	callout_reset(&sc->sc_tick_ch, hz, ste_tick, sc);
1089 }
1090 
1091 /*
1092  * ste_stats_update:
1093  *
1094  *	Read the ST-201 statistics counters.
1095  */
1096 void
1097 ste_stats_update(struct ste_softc *sc)
1098 {
1099 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1100 	bus_space_tag_t st = sc->sc_st;
1101 	bus_space_handle_t sh = sc->sc_sh;
1102 
1103 	(void) bus_space_read_2(st, sh, STE_OctetsReceivedOk0);
1104 	(void) bus_space_read_2(st, sh, STE_OctetsReceivedOk1);
1105 
1106 	(void) bus_space_read_2(st, sh, STE_OctetsTransmittedOk0);
1107 	(void) bus_space_read_2(st, sh, STE_OctetsTransmittedOk1);
1108 
1109 	ifp->if_opackets +=
1110 	    (u_int) bus_space_read_2(st, sh, STE_FramesTransmittedOK);
1111 	ifp->if_ipackets +=
1112 	    (u_int) bus_space_read_2(st, sh, STE_FramesReceivedOK);
1113 
1114 	(void) bus_space_read_2(st, sh, STE_CarrierSenseErrors);
1115 
1116 	ifp->if_collisions +=
1117 	    (u_int) bus_space_read_1(st, sh, STE_LateCollisions) +
1118 	    (u_int) bus_space_read_1(st, sh, STE_MultipleColFrames) +
1119 	    (u_int) bus_space_read_1(st, sh, STE_SingleColFrames);
1120 
1121 	(void) bus_space_read_1(st, sh, STE_FramesWDeferredXmt);
1122 
1123 	ifp->if_ierrors +=
1124 	    (u_int) bus_space_read_1(st, sh, STE_FramesLostRxErrors);
1125 
1126 	ifp->if_oerrors +=
1127 	    (u_int) bus_space_read_1(st, sh, STE_FramesWExDeferral) +
1128 	    (u_int) bus_space_read_1(st, sh, STE_FramesXbortXSColls);
1129 
1130 	(void) bus_space_read_1(st, sh, STE_BcstFramesXmtdOk);
1131 	(void) bus_space_read_1(st, sh, STE_BcstFramesRcvdOk);
1132 	(void) bus_space_read_1(st, sh, STE_McstFramesXmtdOk);
1133 	(void) bus_space_read_1(st, sh, STE_McstFramesRcvdOk);
1134 }
1135 
1136 /*
1137  * ste_reset:
1138  *
1139  *	Perform a soft reset on the ST-201.
1140  */
1141 void
1142 ste_reset(struct ste_softc *sc)
1143 {
1144 	uint32_t ac;
1145 	int i;
1146 
1147 	ac = bus_space_read_4(sc->sc_st, sc->sc_sh, STE_AsicCtrl);
1148 
1149 	bus_space_write_4(sc->sc_st, sc->sc_sh, STE_AsicCtrl,
1150 	    ac | AC_GlobalReset | AC_RxReset | AC_TxReset |
1151 	    AC_DMA | AC_FIFO | AC_Network | AC_Host | AC_AutoInit |
1152 	    AC_RstOut);
1153 
1154 	delay(50000);
1155 
1156 	for (i = 0; i < STE_TIMEOUT; i++) {
1157 		delay(1000);
1158 		if ((bus_space_read_4(sc->sc_st, sc->sc_sh, STE_AsicCtrl) &
1159 		     AC_ResetBusy) == 0)
1160 			break;
1161 	}
1162 
1163 	if (i == STE_TIMEOUT)
1164 		printf("%s: reset failed to complete\n", sc->sc_dev.dv_xname);
1165 
1166 	delay(1000);
1167 }
1168 
1169 /*
1170  * ste_init:		[ ifnet interface function ]
1171  *
1172  *	Initialize the interface.  Must be called at splnet().
1173  */
1174 int
1175 ste_init(struct ifnet *ifp)
1176 {
1177 	struct ste_softc *sc = ifp->if_softc;
1178 	bus_space_tag_t st = sc->sc_st;
1179 	bus_space_handle_t sh = sc->sc_sh;
1180 	struct ste_descsoft *ds;
1181 	int i, error = 0;
1182 
1183 	/*
1184 	 * Cancel any pending I/O.
1185 	 */
1186 	ste_stop(ifp, 0);
1187 
1188 	/*
1189 	 * Reset the chip to a known state.
1190 	 */
1191 	ste_reset(sc);
1192 
1193 	/*
1194 	 * Initialize the transmit descriptor ring.
1195 	 */
1196 	memset(sc->sc_txdescs, 0, sizeof(sc->sc_txdescs));
1197 	sc->sc_txpending = 0;
1198 	sc->sc_txdirty = 0;
1199 	sc->sc_txlast = STE_NTXDESC - 1;
1200 
1201 	/*
1202 	 * Initialize the receive descriptor and receive job
1203 	 * descriptor rings.
1204 	 */
1205 	for (i = 0; i < STE_NRXDESC; i++) {
1206 		ds = &sc->sc_rxsoft[i];
1207 		if (ds->ds_mbuf == NULL) {
1208 			if ((error = ste_add_rxbuf(sc, i)) != 0) {
1209 				printf("%s: unable to allocate or map rx "
1210 				    "buffer %d, error = %d\n",
1211 				    sc->sc_dev.dv_xname, i, error);
1212 				/*
1213 				 * XXX Should attempt to run with fewer receive
1214 				 * XXX buffers instead of just failing.
1215 				 */
1216 				ste_rxdrain(sc);
1217 				goto out;
1218 			}
1219 		} else
1220 			STE_INIT_RXDESC(sc, i);
1221 	}
1222 	sc->sc_rxptr = 0;
1223 
1224 	/* Set the station address. */
1225 	for (i = 0; i < ETHER_ADDR_LEN; i++)
1226 		bus_space_write_1(st, sh, STE_StationAddress0 + 1,
1227 		    LLADDR(ifp->if_sadl)[i]);
1228 
1229 	/* Set up the receive filter. */
1230 	ste_set_filter(sc);
1231 
1232 	/*
1233 	 * Give the receive ring to the chip.
1234 	 */
1235 	bus_space_write_4(st, sh, STE_RxDMAListPtr,
1236 	    STE_CDRXADDR(sc, sc->sc_rxptr));
1237 
1238 	/*
1239 	 * We defer giving the transmit ring to the chip until we
1240 	 * transmit the first packet.
1241 	 */
1242 
1243 	/*
1244 	 * Initialize the Tx auto-poll period.  It's OK to make this number
1245 	 * large (127 is the max) -- we explicitly kick the transmit engine
1246 	 * when there's actually a packet.  We are using auto-polling only
1247 	 * to make the interface to the transmit engine not suck.
1248 	 */
1249 	bus_space_write_1(sc->sc_st, sc->sc_sh, STE_TxDMAPollPeriod, 127);
1250 
1251 	/* ..and the Rx auto-poll period. */
1252 	bus_space_write_1(st, sh, STE_RxDMAPollPeriod, 64);
1253 
1254 	/* Initialize the Tx start threshold. */
1255 	bus_space_write_2(st, sh, STE_TxStartThresh, sc->sc_txthresh);
1256 
1257 	/* Set the FIFO release threshold to 512 bytes. */
1258 	bus_space_write_1(st, sh, STE_TxReleaseThresh, 512 >> 4);
1259 
1260 	/*
1261 	 * Initialize the interrupt mask.
1262 	 */
1263 	sc->sc_IntEnable = IE_HostError | IE_TxComplete | IE_UpdateStats |
1264 	    IE_TxDMAComplete | IE_RxDMAComplete;
1265 	bus_space_write_2(st, sh, STE_IntStatus, 0xffff);
1266 	bus_space_write_2(st, sh, STE_IntEnable, sc->sc_IntEnable);
1267 
1268 	/*
1269 	 * Start the receive DMA engine.
1270 	 */
1271 	bus_space_write_4(st, sh, STE_DMACtrl, sc->sc_DMACtrl | DC_RxDMAResume);
1272 
1273 	/*
1274 	 * Initialize MacCtrl0 -- do it before setting the media,
1275 	 * as setting the media will actually program the register.
1276 	 */
1277 	sc->sc_MacCtrl0 = MC0_IFSSelect(0);
1278 	if (sc->sc_ethercom.ec_capenable & ETHERCAP_VLAN_MTU)
1279 		sc->sc_MacCtrl0 |= MC0_RcvLargeFrames;
1280 
1281 	/*
1282 	 * Set the current media.
1283 	 */
1284 	mii_mediachg(&sc->sc_mii);
1285 
1286 	/*
1287 	 * Start the MAC.
1288 	 */
1289 	bus_space_write_2(st, sh, STE_MacCtrl1,
1290 	    MC1_StatisticsEnable | MC1_TxEnable | MC1_RxEnable);
1291 
1292 	/*
1293 	 * Start the one second MII clock.
1294 	 */
1295 	callout_reset(&sc->sc_tick_ch, hz, ste_tick, sc);
1296 
1297 	/*
1298 	 * ...all done!
1299 	 */
1300 	ifp->if_flags |= IFF_RUNNING;
1301 	ifp->if_flags &= ~IFF_OACTIVE;
1302 
1303  out:
1304 	if (error)
1305 		printf("%s: interface not running\n", sc->sc_dev.dv_xname);
1306 	return (error);
1307 }
1308 
1309 /*
1310  * ste_drain:
1311  *
1312  *	Drain the receive queue.
1313  */
1314 void
1315 ste_rxdrain(struct ste_softc *sc)
1316 {
1317 	struct ste_descsoft *ds;
1318 	int i;
1319 
1320 	for (i = 0; i < STE_NRXDESC; i++) {
1321 		ds = &sc->sc_rxsoft[i];
1322 		if (ds->ds_mbuf != NULL) {
1323 			bus_dmamap_unload(sc->sc_dmat, ds->ds_dmamap);
1324 			m_freem(ds->ds_mbuf);
1325 			ds->ds_mbuf = NULL;
1326 		}
1327 	}
1328 }
1329 
1330 /*
1331  * ste_stop:		[ ifnet interface function ]
1332  *
1333  *	Stop transmission on the interface.
1334  */
1335 void
1336 ste_stop(struct ifnet *ifp, int disable)
1337 {
1338 	struct ste_softc *sc = ifp->if_softc;
1339 	struct ste_descsoft *ds;
1340 	int i;
1341 
1342 	/*
1343 	 * Stop the one second clock.
1344 	 */
1345 	callout_stop(&sc->sc_tick_ch);
1346 
1347 	/* Down the MII. */
1348 	mii_down(&sc->sc_mii);
1349 
1350 	/*
1351 	 * Disable interrupts.
1352 	 */
1353 	bus_space_write_2(sc->sc_st, sc->sc_sh, STE_IntEnable, 0);
1354 
1355 	/*
1356 	 * Stop receiver, transmitter, and stats update.
1357 	 */
1358 	bus_space_write_2(sc->sc_st, sc->sc_sh, STE_MacCtrl1,
1359 	    MC1_StatisticsDisable | MC1_TxDisable | MC1_RxDisable);
1360 
1361 	/*
1362 	 * Stop the transmit and receive DMA.
1363 	 */
1364 	bus_space_write_4(sc->sc_st, sc->sc_sh, STE_DMACtrl,
1365 	    DC_RxDMAHalt | DC_TxDMAHalt);
1366 	ste_dmahalt_wait(sc);
1367 
1368 	/*
1369 	 * Release any queued transmit buffers.
1370 	 */
1371 	for (i = 0; i < STE_NTXDESC; i++) {
1372 		ds = &sc->sc_txsoft[i];
1373 		if (ds->ds_mbuf != NULL) {
1374 			bus_dmamap_unload(sc->sc_dmat, ds->ds_dmamap);
1375 			m_freem(ds->ds_mbuf);
1376 			ds->ds_mbuf = NULL;
1377 		}
1378 	}
1379 
1380 	if (disable)
1381 		ste_rxdrain(sc);
1382 
1383 	/*
1384 	 * Mark the interface down and cancel the watchdog timer.
1385 	 */
1386 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
1387 	ifp->if_timer = 0;
1388 }
1389 
1390 static int
1391 ste_eeprom_wait(struct ste_softc *sc)
1392 {
1393 	int i;
1394 
1395 	for (i = 0; i < STE_TIMEOUT; i++) {
1396 		delay(1000);
1397 		if ((bus_space_read_2(sc->sc_st, sc->sc_sh, STE_EepromCtrl) &
1398 		     EC_EepromBusy) == 0)
1399 			return (0);
1400 	}
1401 	return (1);
1402 }
1403 
1404 /*
1405  * ste_read_eeprom:
1406  *
1407  *	Read data from the serial EEPROM.
1408  */
1409 void
1410 ste_read_eeprom(struct ste_softc *sc, int offset, uint16_t *data)
1411 {
1412 
1413 	if (ste_eeprom_wait(sc))
1414 		printf("%s: EEPROM failed to come ready\n",
1415 		    sc->sc_dev.dv_xname);
1416 
1417 	bus_space_write_2(sc->sc_st, sc->sc_sh, STE_EepromCtrl,
1418 	    EC_EepromAddress(offset) | EC_EepromOpcode(EC_OP_R));
1419 	if (ste_eeprom_wait(sc))
1420 		printf("%s: EEPROM read timed out\n",
1421 		    sc->sc_dev.dv_xname);
1422 	*data = bus_space_read_2(sc->sc_st, sc->sc_sh, STE_EepromData);
1423 }
1424 
1425 /*
1426  * ste_add_rxbuf:
1427  *
1428  *	Add a receive buffer to the indicated descriptor.
1429  */
1430 int
1431 ste_add_rxbuf(struct ste_softc *sc, int idx)
1432 {
1433 	struct ste_descsoft *ds = &sc->sc_rxsoft[idx];
1434 	struct mbuf *m;
1435 	int error;
1436 
1437 	MGETHDR(m, M_DONTWAIT, MT_DATA);
1438 	if (m == NULL)
1439 		return (ENOBUFS);
1440 
1441 	MCLGET(m, M_DONTWAIT);
1442 	if ((m->m_flags & M_EXT) == 0) {
1443 		m_freem(m);
1444 		return (ENOBUFS);
1445 	}
1446 
1447 	if (ds->ds_mbuf != NULL)
1448 		bus_dmamap_unload(sc->sc_dmat, ds->ds_dmamap);
1449 
1450 	ds->ds_mbuf = m;
1451 
1452 	error = bus_dmamap_load(sc->sc_dmat, ds->ds_dmamap,
1453 	    m->m_ext.ext_buf, m->m_ext.ext_size, NULL,
1454 	    BUS_DMA_READ|BUS_DMA_NOWAIT);
1455 	if (error) {
1456 		printf("%s: can't load rx DMA map %d, error = %d\n",
1457 		    sc->sc_dev.dv_xname, idx, error);
1458 		panic("ste_add_rxbuf");		/* XXX */
1459 	}
1460 
1461 	bus_dmamap_sync(sc->sc_dmat, ds->ds_dmamap, 0,
1462 	    ds->ds_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
1463 
1464 	STE_INIT_RXDESC(sc, idx);
1465 
1466 	return (0);
1467 }
1468 
1469 /*
1470  * ste_set_filter:
1471  *
1472  *	Set up the receive filter.
1473  */
1474 void
1475 ste_set_filter(struct ste_softc *sc)
1476 {
1477 	struct ethercom *ec = &sc->sc_ethercom;
1478 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1479 	struct ether_multi *enm;
1480 	struct ether_multistep step;
1481 	uint32_t crc;
1482 	uint16_t mchash[4];
1483 
1484 	sc->sc_ReceiveMode = RM_ReceiveUnicast;
1485 	if (ifp->if_flags & IFF_BROADCAST)
1486 		sc->sc_ReceiveMode |= RM_ReceiveBroadcast;
1487 
1488 	if (ifp->if_flags & IFF_PROMISC) {
1489 		sc->sc_ReceiveMode |= RM_ReceiveAllFrames;
1490 		goto allmulti;
1491 	}
1492 
1493 	/*
1494 	 * Set up the multicast address filter by passing all multicast
1495 	 * addresses through a CRC generator, and then using the low-order
1496 	 * 6 bits as an index into the 64 bit multicast hash table.  The
1497 	 * high order bits select the register, while the rest of the bits
1498 	 * select the bit within the register.
1499 	 */
1500 
1501 	memset(mchash, 0, sizeof(mchash));
1502 
1503 	ETHER_FIRST_MULTI(step, ec, enm);
1504 	if (enm == NULL)
1505 		goto done;
1506 
1507 	while (enm != NULL) {
1508 		if (memcmp(enm->enm_addrlo, enm->enm_addrhi, ETHER_ADDR_LEN)) {
1509 			/*
1510 			 * We must listen to a range of multicast addresses.
1511 			 * For now, just accept all multicasts, rather than
1512 			 * trying to set only those filter bits needed to match
1513 			 * the range.  (At this time, the only use of address
1514 			 * ranges is for IP multicast routing, for which the
1515 			 * range is big enough to require all bits set.)
1516 			 */
1517 			goto allmulti;
1518 		}
1519 
1520 		crc = ether_crc32_be(enm->enm_addrlo, ETHER_ADDR_LEN);
1521 
1522 		/* Just want the 6 least significant bits. */
1523 		crc &= 0x3f;
1524 
1525 		/* Set the corresponding bit in the hash table. */
1526 		mchash[crc >> 4] |= 1 << (crc & 0xf);
1527 
1528 		ETHER_NEXT_MULTI(step, enm);
1529 	}
1530 
1531 	sc->sc_ReceiveMode |= RM_ReceiveMulticastHash;
1532 
1533 	ifp->if_flags &= ~IFF_ALLMULTI;
1534 	goto done;
1535 
1536  allmulti:
1537 	ifp->if_flags |= IFF_ALLMULTI;
1538 	sc->sc_ReceiveMode |= RM_ReceiveMulticast;
1539 
1540  done:
1541 	if ((ifp->if_flags & IFF_ALLMULTI) == 0) {
1542 		/*
1543 		 * Program the multicast hash table.
1544 		 */
1545 		bus_space_write_2(sc->sc_st, sc->sc_sh, STE_HashTable0,
1546 		    mchash[0]);
1547 		bus_space_write_2(sc->sc_st, sc->sc_sh, STE_HashTable1,
1548 		    mchash[1]);
1549 		bus_space_write_2(sc->sc_st, sc->sc_sh, STE_HashTable2,
1550 		    mchash[2]);
1551 		bus_space_write_2(sc->sc_st, sc->sc_sh, STE_HashTable3,
1552 		    mchash[3]);
1553 	}
1554 
1555 	bus_space_write_1(sc->sc_st, sc->sc_sh, STE_ReceiveMode,
1556 	    sc->sc_ReceiveMode);
1557 }
1558 
1559 /*
1560  * ste_mii_readreg:	[mii interface function]
1561  *
1562  *	Read a PHY register on the MII of the ST-201.
1563  */
1564 int
1565 ste_mii_readreg(struct device *self, int phy, int reg)
1566 {
1567 
1568 	return (mii_bitbang_readreg(self, &ste_mii_bitbang_ops, phy, reg));
1569 }
1570 
1571 /*
1572  * ste_mii_writereg:	[mii interface function]
1573  *
1574  *	Write a PHY register on the MII of the ST-201.
1575  */
1576 void
1577 ste_mii_writereg(struct device *self, int phy, int reg, int val)
1578 {
1579 
1580 	mii_bitbang_writereg(self, &ste_mii_bitbang_ops, phy, reg, val);
1581 }
1582 
1583 /*
1584  * ste_mii_statchg:	[mii interface function]
1585  *
1586  *	Callback from MII layer when media changes.
1587  */
1588 void
1589 ste_mii_statchg(struct device *self)
1590 {
1591 	struct ste_softc *sc = (struct ste_softc *) self;
1592 
1593 	if (sc->sc_mii.mii_media_active & IFM_FDX)
1594 		sc->sc_MacCtrl0 |= MC0_FullDuplexEnable;
1595 	else
1596 		sc->sc_MacCtrl0 &= ~MC0_FullDuplexEnable;
1597 
1598 	/* XXX 802.1x flow-control? */
1599 
1600 	bus_space_write_2(sc->sc_st, sc->sc_sh, STE_MacCtrl0, sc->sc_MacCtrl0);
1601 }
1602 
1603 /*
1604  * ste_mii_bitbang_read: [mii bit-bang interface function]
1605  *
1606  *	Read the MII serial port for the MII bit-bang module.
1607  */
1608 uint32_t
1609 ste_mii_bitbang_read(struct device *self)
1610 {
1611 	struct ste_softc *sc = (void *) self;
1612 
1613 	return (bus_space_read_1(sc->sc_st, sc->sc_sh, STE_PhyCtrl));
1614 }
1615 
1616 /*
1617  * ste_mii_bitbang_write: [mii big-bang interface function]
1618  *
1619  *	Write the MII serial port for the MII bit-bang module.
1620  */
1621 void
1622 ste_mii_bitbang_write(struct device *self, uint32_t val)
1623 {
1624 	struct ste_softc *sc = (void *) self;
1625 
1626 	bus_space_write_1(sc->sc_st, sc->sc_sh, STE_PhyCtrl, val);
1627 }
1628 
1629 /*
1630  * ste_mediastatus:	[ifmedia interface function]
1631  *
1632  *	Get the current interface media status.
1633  */
1634 void
1635 ste_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
1636 {
1637 	struct ste_softc *sc = ifp->if_softc;
1638 
1639 	mii_pollstat(&sc->sc_mii);
1640 	ifmr->ifm_status = sc->sc_mii.mii_media_status;
1641 	ifmr->ifm_active = sc->sc_mii.mii_media_active;
1642 }
1643 
1644 /*
1645  * ste_mediachange:	[ifmedia interface function]
1646  *
1647  *	Set hardware to newly-selected media.
1648  */
1649 int
1650 ste_mediachange(struct ifnet *ifp)
1651 {
1652 	struct ste_softc *sc = ifp->if_softc;
1653 
1654 	if (ifp->if_flags & IFF_UP)
1655 		mii_mediachg(&sc->sc_mii);
1656 	return (0);
1657 }
1658