xref: /freebsd/sys/dev/sis/if_sis.c (revision dd21556857e8d40f66bf5ad54754d9d52669ebf7)
1 /*-
2  * SPDX-License-Identifier: BSD-4-Clause
3  *
4  * Copyright (c) 2005 Poul-Henning Kamp <phk@FreeBSD.org>
5  * Copyright (c) 1997, 1998, 1999
6  *	Bill Paul <wpaul@ctr.columbia.edu>.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by Bill Paul.
19  * 4. Neither the name of the author nor the names of any co-contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR THE VOICES IN HIS HEAD
27  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
31  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
33  * THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 /*
38  * SiS 900/SiS 7016 fast ethernet PCI NIC driver. Datasheets are
39  * available from http://www.sis.com.tw.
40  *
41  * This driver also supports the NatSemi DP83815. Datasheets are
42  * available from http://www.national.com.
43  *
44  * Written by Bill Paul <wpaul@ee.columbia.edu>
45  * Electrical Engineering Department
46  * Columbia University, New York City
47  */
48 /*
49  * The SiS 900 is a fairly simple chip. It uses bus master DMA with
50  * simple TX and RX descriptors of 3 longwords in size. The receiver
51  * has a single perfect filter entry for the station address and a
52  * 128-bit multicast hash table. The SiS 900 has a built-in MII-based
53  * transceiver while the 7016 requires an external transceiver chip.
54  * Both chips offer the standard bit-bang MII interface as well as
55  * an enchanced PHY interface which simplifies accessing MII registers.
56  *
57  * The only downside to this chipset is that RX descriptors must be
58  * longword aligned.
59  */
60 
61 #ifdef HAVE_KERNEL_OPTION_HEADERS
62 #include "opt_device_polling.h"
63 #endif
64 
65 #include <sys/param.h>
66 #include <sys/systm.h>
67 #include <sys/bus.h>
68 #include <sys/endian.h>
69 #include <sys/kernel.h>
70 #include <sys/lock.h>
71 #include <sys/malloc.h>
72 #include <sys/mbuf.h>
73 #include <sys/module.h>
74 #include <sys/socket.h>
75 #include <sys/sockio.h>
76 #include <sys/sysctl.h>
77 
78 #include <net/if.h>
79 #include <net/if_var.h>
80 #include <net/if_arp.h>
81 #include <net/ethernet.h>
82 #include <net/if_dl.h>
83 #include <net/if_media.h>
84 #include <net/if_types.h>
85 #include <net/if_vlan_var.h>
86 
87 #include <net/bpf.h>
88 
89 #include <machine/bus.h>
90 #include <machine/resource.h>
91 #include <sys/rman.h>
92 
93 #include <dev/mii/mii.h>
94 #include <dev/mii/mii_bitbang.h>
95 #include <dev/mii/miivar.h>
96 
97 #include <dev/pci/pcireg.h>
98 #include <dev/pci/pcivar.h>
99 
100 #define SIS_USEIOSPACE
101 
102 #include <dev/sis/if_sisreg.h>
103 
104 MODULE_DEPEND(sis, pci, 1, 1, 1);
105 MODULE_DEPEND(sis, ether, 1, 1, 1);
106 MODULE_DEPEND(sis, miibus, 1, 1, 1);
107 
108 /* "device miibus" required.  See GENERIC if you get errors here. */
109 #include "miibus_if.h"
110 
111 #define	SIS_LOCK(_sc)		mtx_lock(&(_sc)->sis_mtx)
112 #define	SIS_UNLOCK(_sc)		mtx_unlock(&(_sc)->sis_mtx)
113 #define	SIS_LOCK_ASSERT(_sc)	mtx_assert(&(_sc)->sis_mtx, MA_OWNED)
114 
115 /*
116  * register space access macros
117  */
118 #define CSR_WRITE_4(sc, reg, val)	bus_write_4(sc->sis_res[0], reg, val)
119 
120 #define CSR_READ_4(sc, reg)		bus_read_4(sc->sis_res[0], reg)
121 
122 #define CSR_READ_2(sc, reg)		bus_read_2(sc->sis_res[0], reg)
123 
124 #define	CSR_BARRIER(sc, reg, length, flags)				\
125 	bus_barrier(sc->sis_res[0], reg, length, flags)
126 
127 /*
128  * Various supported device vendors/types and their names.
129  */
130 static const struct sis_type sis_devs[] = {
131 	{ SIS_VENDORID, SIS_DEVICEID_900, "SiS 900 10/100BaseTX" },
132 	{ SIS_VENDORID, SIS_DEVICEID_7016, "SiS 7016 10/100BaseTX" },
133 	{ NS_VENDORID, NS_DEVICEID_DP83815, "NatSemi DP8381[56] 10/100BaseTX" },
134 	{ 0, 0, NULL }
135 };
136 
137 static int sis_detach(device_t);
138 static __inline void sis_discard_rxbuf(struct sis_rxdesc *);
139 static int sis_dma_alloc(struct sis_softc *);
140 static void sis_dma_free(struct sis_softc *);
141 static int sis_dma_ring_alloc(struct sis_softc *, bus_size_t, bus_size_t,
142     bus_dma_tag_t *, uint8_t **, bus_dmamap_t *, bus_addr_t *, const char *);
143 static void sis_dmamap_cb(void *, bus_dma_segment_t *, int, int);
144 #ifndef __NO_STRICT_ALIGNMENT
145 static __inline void sis_fixup_rx(struct mbuf *);
146 #endif
147 static void sis_ifmedia_sts(if_t, struct ifmediareq *);
148 static int sis_ifmedia_upd(if_t);
149 static void sis_init(void *);
150 static void sis_initl(struct sis_softc *);
151 static void sis_intr(void *);
152 static int sis_ioctl(if_t, u_long, caddr_t);
153 static uint32_t sis_mii_bitbang_read(device_t);
154 static void sis_mii_bitbang_write(device_t, uint32_t);
155 static int sis_newbuf(struct sis_softc *, struct sis_rxdesc *);
156 static int sis_resume(device_t);
157 static int sis_rxeof(struct sis_softc *);
158 static void sis_rxfilter(struct sis_softc *);
159 static void sis_rxfilter_ns(struct sis_softc *);
160 static void sis_rxfilter_sis(struct sis_softc *);
161 static void sis_start(if_t);
162 static void sis_startl(if_t);
163 static void sis_stop(struct sis_softc *);
164 static int sis_suspend(device_t);
165 static void sis_add_sysctls(struct sis_softc *);
166 static void sis_watchdog(struct sis_softc *);
167 static void sis_wol(struct sis_softc *);
168 
169 /*
170  * MII bit-bang glue
171  */
172 static const struct mii_bitbang_ops sis_mii_bitbang_ops = {
173 	sis_mii_bitbang_read,
174 	sis_mii_bitbang_write,
175 	{
176 		SIS_MII_DATA,		/* MII_BIT_MDO */
177 		SIS_MII_DATA,		/* MII_BIT_MDI */
178 		SIS_MII_CLK,		/* MII_BIT_MDC */
179 		SIS_MII_DIR,		/* MII_BIT_DIR_HOST_PHY */
180 		0,			/* MII_BIT_DIR_PHY_HOST */
181 	}
182 };
183 
184 static struct resource_spec sis_res_spec[] = {
185 #ifdef SIS_USEIOSPACE
186 	{ SYS_RES_IOPORT,	SIS_PCI_LOIO,	RF_ACTIVE},
187 #else
188 	{ SYS_RES_MEMORY,	SIS_PCI_LOMEM,	RF_ACTIVE},
189 #endif
190 	{ SYS_RES_IRQ,		0,		RF_ACTIVE | RF_SHAREABLE},
191 	{ -1, 0 }
192 };
193 
194 #define SIS_SETBIT(sc, reg, x)				\
195 	CSR_WRITE_4(sc, reg,				\
196 		CSR_READ_4(sc, reg) | (x))
197 
198 #define SIS_CLRBIT(sc, reg, x)				\
199 	CSR_WRITE_4(sc, reg,				\
200 		CSR_READ_4(sc, reg) & ~(x))
201 
202 #define SIO_SET(x)					\
203 	CSR_WRITE_4(sc, SIS_EECTL, CSR_READ_4(sc, SIS_EECTL) | x)
204 
205 #define SIO_CLR(x)					\
206 	CSR_WRITE_4(sc, SIS_EECTL, CSR_READ_4(sc, SIS_EECTL) & ~x)
207 
208 /*
209  * Routine to reverse the bits in a word. Stolen almost
210  * verbatim from /usr/games/fortune.
211  */
212 static uint16_t
213 sis_reverse(uint16_t n)
214 {
215 	n = ((n >>  1) & 0x5555) | ((n <<  1) & 0xaaaa);
216 	n = ((n >>  2) & 0x3333) | ((n <<  2) & 0xcccc);
217 	n = ((n >>  4) & 0x0f0f) | ((n <<  4) & 0xf0f0);
218 	n = ((n >>  8) & 0x00ff) | ((n <<  8) & 0xff00);
219 
220 	return (n);
221 }
222 
223 static void
224 sis_delay(struct sis_softc *sc)
225 {
226 	int			idx;
227 
228 	for (idx = (300 / 33) + 1; idx > 0; idx--)
229 		CSR_READ_4(sc, SIS_CSR);
230 }
231 
232 static void
233 sis_eeprom_idle(struct sis_softc *sc)
234 {
235 	int		i;
236 
237 	SIO_SET(SIS_EECTL_CSEL);
238 	sis_delay(sc);
239 	SIO_SET(SIS_EECTL_CLK);
240 	sis_delay(sc);
241 
242 	for (i = 0; i < 25; i++) {
243 		SIO_CLR(SIS_EECTL_CLK);
244 		sis_delay(sc);
245 		SIO_SET(SIS_EECTL_CLK);
246 		sis_delay(sc);
247 	}
248 
249 	SIO_CLR(SIS_EECTL_CLK);
250 	sis_delay(sc);
251 	SIO_CLR(SIS_EECTL_CSEL);
252 	sis_delay(sc);
253 	CSR_WRITE_4(sc, SIS_EECTL, 0x00000000);
254 }
255 
256 /*
257  * Send a read command and address to the EEPROM, check for ACK.
258  */
259 static void
260 sis_eeprom_putbyte(struct sis_softc *sc, int addr)
261 {
262 	int		d, i;
263 
264 	d = addr | SIS_EECMD_READ;
265 
266 	/*
267 	 * Feed in each bit and stobe the clock.
268 	 */
269 	for (i = 0x400; i; i >>= 1) {
270 		if (d & i) {
271 			SIO_SET(SIS_EECTL_DIN);
272 		} else {
273 			SIO_CLR(SIS_EECTL_DIN);
274 		}
275 		sis_delay(sc);
276 		SIO_SET(SIS_EECTL_CLK);
277 		sis_delay(sc);
278 		SIO_CLR(SIS_EECTL_CLK);
279 		sis_delay(sc);
280 	}
281 }
282 
283 /*
284  * Read a word of data stored in the EEPROM at address 'addr.'
285  */
286 static void
287 sis_eeprom_getword(struct sis_softc *sc, int addr, uint16_t *dest)
288 {
289 	int		i;
290 	uint16_t	word = 0;
291 
292 	/* Force EEPROM to idle state. */
293 	sis_eeprom_idle(sc);
294 
295 	/* Enter EEPROM access mode. */
296 	sis_delay(sc);
297 	SIO_CLR(SIS_EECTL_CLK);
298 	sis_delay(sc);
299 	SIO_SET(SIS_EECTL_CSEL);
300 	sis_delay(sc);
301 
302 	/*
303 	 * Send address of word we want to read.
304 	 */
305 	sis_eeprom_putbyte(sc, addr);
306 
307 	/*
308 	 * Start reading bits from EEPROM.
309 	 */
310 	for (i = 0x8000; i; i >>= 1) {
311 		SIO_SET(SIS_EECTL_CLK);
312 		sis_delay(sc);
313 		if (CSR_READ_4(sc, SIS_EECTL) & SIS_EECTL_DOUT)
314 			word |= i;
315 		sis_delay(sc);
316 		SIO_CLR(SIS_EECTL_CLK);
317 		sis_delay(sc);
318 	}
319 
320 	/* Turn off EEPROM access mode. */
321 	sis_eeprom_idle(sc);
322 
323 	*dest = word;
324 }
325 
326 /*
327  * Read a sequence of words from the EEPROM.
328  */
329 static void
330 sis_read_eeprom(struct sis_softc *sc, caddr_t dest, int off, int cnt, int swap)
331 {
332 	int			i;
333 	uint16_t		word = 0, *ptr;
334 
335 	for (i = 0; i < cnt; i++) {
336 		sis_eeprom_getword(sc, off + i, &word);
337 		ptr = (uint16_t *)(dest + (i * 2));
338 		if (swap)
339 			*ptr = ntohs(word);
340 		else
341 			*ptr = word;
342 	}
343 }
344 
345 #if defined(__i386__) || defined(__amd64__)
346 static device_t
347 sis_find_bridge(device_t dev)
348 {
349 	devclass_t		pci_devclass;
350 	device_t		*pci_devices;
351 	int			pci_count = 0;
352 	device_t		*pci_children;
353 	int			pci_childcount = 0;
354 	device_t		*busp, *childp;
355 	device_t		child = NULL;
356 	int			i, j;
357 
358 	if ((pci_devclass = devclass_find("pci")) == NULL)
359 		return (NULL);
360 
361 	devclass_get_devices(pci_devclass, &pci_devices, &pci_count);
362 
363 	for (i = 0, busp = pci_devices; i < pci_count; i++, busp++) {
364 		if (device_get_children(*busp, &pci_children, &pci_childcount))
365 			continue;
366 		for (j = 0, childp = pci_children;
367 		    j < pci_childcount; j++, childp++) {
368 			if (pci_get_vendor(*childp) == SIS_VENDORID &&
369 			    pci_get_device(*childp) == 0x0008) {
370 				child = *childp;
371 				free(pci_children, M_TEMP);
372 				goto done;
373 			}
374 		}
375 		free(pci_children, M_TEMP);
376 	}
377 
378 done:
379 	free(pci_devices, M_TEMP);
380 	return (child);
381 }
382 
383 static void
384 sis_read_cmos(struct sis_softc *sc, device_t dev, caddr_t dest, int off, int cnt)
385 {
386 	device_t		bridge;
387 	uint8_t			reg;
388 	int			i;
389 	bus_space_tag_t		btag;
390 
391 	bridge = sis_find_bridge(dev);
392 	if (bridge == NULL)
393 		return;
394 	reg = pci_read_config(bridge, 0x48, 1);
395 	pci_write_config(bridge, 0x48, reg|0x40, 1);
396 
397 	/* XXX */
398 #if defined(__amd64__) || defined(__i386__)
399 	btag = X86_BUS_SPACE_IO;
400 #endif
401 
402 	for (i = 0; i < cnt; i++) {
403 		bus_space_write_1(btag, 0x0, 0x70, i + off);
404 		*(dest + i) = bus_space_read_1(btag, 0x0, 0x71);
405 	}
406 
407 	pci_write_config(bridge, 0x48, reg & ~0x40, 1);
408 }
409 
410 static void
411 sis_read_mac(struct sis_softc *sc, device_t dev, caddr_t dest)
412 {
413 	uint32_t		filtsave, csrsave;
414 
415 	filtsave = CSR_READ_4(sc, SIS_RXFILT_CTL);
416 	csrsave = CSR_READ_4(sc, SIS_CSR);
417 
418 	CSR_WRITE_4(sc, SIS_CSR, SIS_CSR_RELOAD | filtsave);
419 	CSR_WRITE_4(sc, SIS_CSR, 0);
420 
421 	CSR_WRITE_4(sc, SIS_RXFILT_CTL, filtsave & ~SIS_RXFILTCTL_ENABLE);
422 
423 	CSR_WRITE_4(sc, SIS_RXFILT_CTL, SIS_FILTADDR_PAR0);
424 	((uint16_t *)dest)[0] = CSR_READ_2(sc, SIS_RXFILT_DATA);
425 	CSR_WRITE_4(sc, SIS_RXFILT_CTL,SIS_FILTADDR_PAR1);
426 	((uint16_t *)dest)[1] = CSR_READ_2(sc, SIS_RXFILT_DATA);
427 	CSR_WRITE_4(sc, SIS_RXFILT_CTL, SIS_FILTADDR_PAR2);
428 	((uint16_t *)dest)[2] = CSR_READ_2(sc, SIS_RXFILT_DATA);
429 
430 	CSR_WRITE_4(sc, SIS_RXFILT_CTL, filtsave);
431 	CSR_WRITE_4(sc, SIS_CSR, csrsave);
432 }
433 #endif
434 
435 /*
436  * Read the MII serial port for the MII bit-bang module.
437  */
438 static uint32_t
439 sis_mii_bitbang_read(device_t dev)
440 {
441 	struct sis_softc	*sc;
442 	uint32_t		val;
443 
444 	sc = device_get_softc(dev);
445 
446 	val = CSR_READ_4(sc, SIS_EECTL);
447 	CSR_BARRIER(sc, SIS_EECTL, 4,
448 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
449 	return (val);
450 }
451 
452 /*
453  * Write the MII serial port for the MII bit-bang module.
454  */
455 static void
456 sis_mii_bitbang_write(device_t dev, uint32_t val)
457 {
458 	struct sis_softc	*sc;
459 
460 	sc = device_get_softc(dev);
461 
462 	CSR_WRITE_4(sc, SIS_EECTL, val);
463 	CSR_BARRIER(sc, SIS_EECTL, 4,
464 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
465 }
466 
467 static int
468 sis_miibus_readreg(device_t dev, int phy, int reg)
469 {
470 	struct sis_softc	*sc;
471 
472 	sc = device_get_softc(dev);
473 
474 	if (sc->sis_type == SIS_TYPE_83815) {
475 		if (phy != 0)
476 			return (0);
477 		/*
478 		 * The NatSemi chip can take a while after
479 		 * a reset to come ready, during which the BMSR
480 		 * returns a value of 0. This is *never* supposed
481 		 * to happen: some of the BMSR bits are meant to
482 		 * be hardwired in the on position, and this can
483 		 * confuse the miibus code a bit during the probe
484 		 * and attach phase. So we make an effort to check
485 		 * for this condition and wait for it to clear.
486 		 */
487 		if (!CSR_READ_4(sc, NS_BMSR))
488 			DELAY(1000);
489 		return CSR_READ_4(sc, NS_BMCR + (reg * 4));
490 	}
491 
492 	/*
493 	 * Chipsets < SIS_635 seem not to be able to read/write
494 	 * through mdio. Use the enhanced PHY access register
495 	 * again for them.
496 	 */
497 	if (sc->sis_type == SIS_TYPE_900 &&
498 	    sc->sis_rev < SIS_REV_635) {
499 		int i, val = 0;
500 
501 		if (phy != 0)
502 			return (0);
503 
504 		CSR_WRITE_4(sc, SIS_PHYCTL,
505 		    (phy << 11) | (reg << 6) | SIS_PHYOP_READ);
506 		SIS_SETBIT(sc, SIS_PHYCTL, SIS_PHYCTL_ACCESS);
507 
508 		for (i = 0; i < SIS_TIMEOUT; i++) {
509 			if (!(CSR_READ_4(sc, SIS_PHYCTL) & SIS_PHYCTL_ACCESS))
510 				break;
511 		}
512 
513 		if (i == SIS_TIMEOUT) {
514 			device_printf(sc->sis_dev,
515 			    "PHY failed to come ready\n");
516 			return (0);
517 		}
518 
519 		val = (CSR_READ_4(sc, SIS_PHYCTL) >> 16) & 0xFFFF;
520 
521 		if (val == 0xFFFF)
522 			return (0);
523 
524 		return (val);
525 	} else
526 		return (mii_bitbang_readreg(dev, &sis_mii_bitbang_ops, phy,
527 		    reg));
528 }
529 
530 static int
531 sis_miibus_writereg(device_t dev, int phy, int reg, int data)
532 {
533 	struct sis_softc	*sc;
534 
535 	sc = device_get_softc(dev);
536 
537 	if (sc->sis_type == SIS_TYPE_83815) {
538 		if (phy != 0)
539 			return (0);
540 		CSR_WRITE_4(sc, NS_BMCR + (reg * 4), data);
541 		return (0);
542 	}
543 
544 	/*
545 	 * Chipsets < SIS_635 seem not to be able to read/write
546 	 * through mdio. Use the enhanced PHY access register
547 	 * again for them.
548 	 */
549 	if (sc->sis_type == SIS_TYPE_900 &&
550 	    sc->sis_rev < SIS_REV_635) {
551 		int i;
552 
553 		if (phy != 0)
554 			return (0);
555 
556 		CSR_WRITE_4(sc, SIS_PHYCTL, (data << 16) | (phy << 11) |
557 		    (reg << 6) | SIS_PHYOP_WRITE);
558 		SIS_SETBIT(sc, SIS_PHYCTL, SIS_PHYCTL_ACCESS);
559 
560 		for (i = 0; i < SIS_TIMEOUT; i++) {
561 			if (!(CSR_READ_4(sc, SIS_PHYCTL) & SIS_PHYCTL_ACCESS))
562 				break;
563 		}
564 
565 		if (i == SIS_TIMEOUT)
566 			device_printf(sc->sis_dev,
567 			    "PHY failed to come ready\n");
568 	} else
569 		mii_bitbang_writereg(dev, &sis_mii_bitbang_ops, phy, reg,
570 		    data);
571 	return (0);
572 }
573 
574 static void
575 sis_miibus_statchg(device_t dev)
576 {
577 	struct sis_softc	*sc;
578 	struct mii_data		*mii;
579 	if_t			ifp;
580 	uint32_t		reg;
581 
582 	sc = device_get_softc(dev);
583 	SIS_LOCK_ASSERT(sc);
584 
585 	mii = device_get_softc(sc->sis_miibus);
586 	ifp = sc->sis_ifp;
587 	if (mii == NULL || ifp == NULL ||
588 	    (if_getdrvflags(ifp) & IFF_DRV_RUNNING) == 0)
589 		return;
590 
591 	sc->sis_flags &= ~SIS_FLAG_LINK;
592 	if ((mii->mii_media_status & (IFM_ACTIVE | IFM_AVALID)) ==
593 	    (IFM_ACTIVE | IFM_AVALID)) {
594 		switch (IFM_SUBTYPE(mii->mii_media_active)) {
595 		case IFM_10_T:
596 			CSR_WRITE_4(sc, SIS_TX_CFG, SIS_TXCFG_10);
597 			sc->sis_flags |= SIS_FLAG_LINK;
598 			break;
599 		case IFM_100_TX:
600 			CSR_WRITE_4(sc, SIS_TX_CFG, SIS_TXCFG_100);
601 			sc->sis_flags |= SIS_FLAG_LINK;
602 			break;
603 		default:
604 			break;
605 		}
606 	}
607 
608 	if ((sc->sis_flags & SIS_FLAG_LINK) == 0) {
609 		/*
610 		 * Stopping MACs seem to reset SIS_TX_LISTPTR and
611 		 * SIS_RX_LISTPTR which in turn requires resetting
612 		 * TX/RX buffers.  So just don't do anything for
613 		 * lost link.
614 		 */
615 		return;
616 	}
617 
618 	/* Set full/half duplex mode. */
619 	if ((IFM_OPTIONS(mii->mii_media_active) & IFM_FDX) != 0) {
620 		SIS_SETBIT(sc, SIS_TX_CFG,
621 		    (SIS_TXCFG_IGN_HBEAT | SIS_TXCFG_IGN_CARR));
622 		SIS_SETBIT(sc, SIS_RX_CFG, SIS_RXCFG_RX_TXPKTS);
623 	} else {
624 		SIS_CLRBIT(sc, SIS_TX_CFG,
625 		    (SIS_TXCFG_IGN_HBEAT | SIS_TXCFG_IGN_CARR));
626 		SIS_CLRBIT(sc, SIS_RX_CFG, SIS_RXCFG_RX_TXPKTS);
627 	}
628 
629 	if (sc->sis_type == SIS_TYPE_83815 && sc->sis_srr >= NS_SRR_16A) {
630 		/*
631 		 * MPII03.D: Half Duplex Excessive Collisions.
632 		 * Also page 49 in 83816 manual
633 		 */
634 		SIS_SETBIT(sc, SIS_TX_CFG, SIS_TXCFG_MPII03D);
635 	}
636 
637 	if (sc->sis_type == SIS_TYPE_83815 && sc->sis_srr < NS_SRR_16A &&
638 	    IFM_SUBTYPE(mii->mii_media_active) == IFM_100_TX) {
639 		/*
640 		 * Short Cable Receive Errors (MP21.E)
641 		 */
642 		CSR_WRITE_4(sc, NS_PHY_PAGE, 0x0001);
643 		reg = CSR_READ_4(sc, NS_PHY_DSPCFG) & 0xfff;
644 		CSR_WRITE_4(sc, NS_PHY_DSPCFG, reg | 0x1000);
645 		DELAY(100);
646 		reg = CSR_READ_4(sc, NS_PHY_TDATA) & 0xff;
647 		if ((reg & 0x0080) == 0 || (reg > 0xd8 && reg <= 0xff)) {
648 			device_printf(sc->sis_dev,
649 			    "Applying short cable fix (reg=%x)\n", reg);
650 			CSR_WRITE_4(sc, NS_PHY_TDATA, 0x00e8);
651 			SIS_SETBIT(sc, NS_PHY_DSPCFG, 0x20);
652 		}
653 		CSR_WRITE_4(sc, NS_PHY_PAGE, 0);
654 	}
655 	/* Enable TX/RX MACs. */
656 	SIS_CLRBIT(sc, SIS_CSR, SIS_CSR_TX_DISABLE | SIS_CSR_RX_DISABLE);
657 	SIS_SETBIT(sc, SIS_CSR, SIS_CSR_TX_ENABLE | SIS_CSR_RX_ENABLE);
658 }
659 
660 static uint32_t
661 sis_mchash(struct sis_softc *sc, const uint8_t *addr)
662 {
663 	uint32_t		crc;
664 
665 	/* Compute CRC for the address value. */
666 	crc = ether_crc32_be(addr, ETHER_ADDR_LEN);
667 
668 	/*
669 	 * return the filter bit position
670 	 *
671 	 * The NatSemi chip has a 512-bit filter, which is
672 	 * different than the SiS, so we special-case it.
673 	 */
674 	if (sc->sis_type == SIS_TYPE_83815)
675 		return (crc >> 23);
676 	else if (sc->sis_rev >= SIS_REV_635 ||
677 	    sc->sis_rev == SIS_REV_900B)
678 		return (crc >> 24);
679 	else
680 		return (crc >> 25);
681 }
682 
683 static void
684 sis_rxfilter(struct sis_softc *sc)
685 {
686 
687 	SIS_LOCK_ASSERT(sc);
688 
689 	if (sc->sis_type == SIS_TYPE_83815)
690 		sis_rxfilter_ns(sc);
691 	else
692 		sis_rxfilter_sis(sc);
693 }
694 
695 static u_int
696 sis_write_maddr(void *arg, struct sockaddr_dl *sdl, u_int cnt)
697 {
698 	struct sis_softc *sc = arg;
699 	uint32_t h;
700 	int bit, index;
701 
702 	h = sis_mchash(sc, LLADDR(sdl));
703 	index = h >> 3;
704 	bit = h & 0x1F;
705 	CSR_WRITE_4(sc, SIS_RXFILT_CTL, NS_FILTADDR_FMEM_LO + index);
706 	if (bit > 0xF)
707 		bit -= 0x10;
708 	SIS_SETBIT(sc, SIS_RXFILT_DATA, (1 << bit));
709 
710 	return (1);
711 }
712 
713 static void
714 sis_rxfilter_ns(struct sis_softc *sc)
715 {
716 	if_t			ifp;
717 	uint32_t		i, filter;
718 
719 	ifp = sc->sis_ifp;
720 	filter = CSR_READ_4(sc, SIS_RXFILT_CTL);
721 	if (filter & SIS_RXFILTCTL_ENABLE) {
722 		/*
723 		 * Filter should be disabled to program other bits.
724 		 */
725 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, filter & ~SIS_RXFILTCTL_ENABLE);
726 		CSR_READ_4(sc, SIS_RXFILT_CTL);
727 	}
728 	filter &= ~(NS_RXFILTCTL_ARP | NS_RXFILTCTL_PERFECT |
729 	    NS_RXFILTCTL_MCHASH | SIS_RXFILTCTL_ALLPHYS | SIS_RXFILTCTL_BROAD |
730 	    SIS_RXFILTCTL_ALLMULTI);
731 
732 	if (if_getflags(ifp) & IFF_BROADCAST)
733 		filter |= SIS_RXFILTCTL_BROAD;
734 	/*
735 	 * For the NatSemi chip, we have to explicitly enable the
736 	 * reception of ARP frames, as well as turn on the 'perfect
737 	 * match' filter where we store the station address, otherwise
738 	 * we won't receive unicasts meant for this host.
739 	 */
740 	filter |= NS_RXFILTCTL_ARP | NS_RXFILTCTL_PERFECT;
741 
742 	if (if_getflags(ifp) & (IFF_ALLMULTI | IFF_PROMISC)) {
743 		filter |= SIS_RXFILTCTL_ALLMULTI;
744 		if (if_getflags(ifp) & IFF_PROMISC)
745 			filter |= SIS_RXFILTCTL_ALLPHYS;
746 	} else {
747 		/*
748 		 * We have to explicitly enable the multicast hash table
749 		 * on the NatSemi chip if we want to use it, which we do.
750 		 */
751 		filter |= NS_RXFILTCTL_MCHASH;
752 
753 		/* first, zot all the existing hash bits */
754 		for (i = 0; i < 32; i++) {
755 			CSR_WRITE_4(sc, SIS_RXFILT_CTL, NS_FILTADDR_FMEM_LO +
756 			    (i * 2));
757 			CSR_WRITE_4(sc, SIS_RXFILT_DATA, 0);
758 		}
759 
760 		if_foreach_llmaddr(ifp, sis_write_maddr, sc);
761 	}
762 
763 	/* Turn the receive filter on */
764 	CSR_WRITE_4(sc, SIS_RXFILT_CTL, filter | SIS_RXFILTCTL_ENABLE);
765 	CSR_READ_4(sc, SIS_RXFILT_CTL);
766 }
767 
768 struct sis_hash_maddr_ctx {
769 	struct sis_softc *sc;
770 	uint16_t hashes[16];
771 };
772 
773 static u_int
774 sis_hash_maddr(void *arg, struct sockaddr_dl *sdl, u_int cnt)
775 {
776 	struct sis_hash_maddr_ctx *ctx = arg;
777 	uint32_t h;
778 
779 	h = sis_mchash(ctx->sc, LLADDR(sdl));
780 	ctx->hashes[h >> 4] |= 1 << (h & 0xf);
781 
782 	return (1);
783 }
784 
785 static void
786 sis_rxfilter_sis(struct sis_softc *sc)
787 {
788 	if_t			ifp;
789 	struct sis_hash_maddr_ctx ctx;
790 	uint32_t		filter, i, n;
791 
792 	ifp = sc->sis_ifp;
793 
794 	/* hash table size */
795 	if (sc->sis_rev >= SIS_REV_635 || sc->sis_rev == SIS_REV_900B)
796 		n = 16;
797 	else
798 		n = 8;
799 
800 	filter = CSR_READ_4(sc, SIS_RXFILT_CTL);
801 	if (filter & SIS_RXFILTCTL_ENABLE) {
802 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, filter & ~SIS_RXFILTCTL_ENABLE);
803 		CSR_READ_4(sc, SIS_RXFILT_CTL);
804 	}
805 	filter &= ~(SIS_RXFILTCTL_ALLPHYS | SIS_RXFILTCTL_BROAD |
806 	    SIS_RXFILTCTL_ALLMULTI);
807 	if (if_getflags(ifp) & IFF_BROADCAST)
808 		filter |= SIS_RXFILTCTL_BROAD;
809 
810 	if (if_getflags(ifp) & (IFF_ALLMULTI | IFF_PROMISC)) {
811 		filter |= SIS_RXFILTCTL_ALLMULTI;
812 		if (if_getflags(ifp) & IFF_PROMISC)
813 			filter |= SIS_RXFILTCTL_ALLPHYS;
814 		for (i = 0; i < n; i++)
815 			ctx.hashes[i] = ~0;
816 	} else {
817 		for (i = 0; i < n; i++)
818 			ctx.hashes[i] = 0;
819 		ctx.sc = sc;
820 		if (if_foreach_llmaddr(ifp, sis_hash_maddr, &ctx) > n) {
821 			filter |= SIS_RXFILTCTL_ALLMULTI;
822 			for (i = 0; i < n; i++)
823 				ctx.hashes[i] = ~0;
824 		}
825 	}
826 
827 	for (i = 0; i < n; i++) {
828 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, (4 + i) << 16);
829 		CSR_WRITE_4(sc, SIS_RXFILT_DATA, ctx.hashes[i]);
830 	}
831 
832 	/* Turn the receive filter on */
833 	CSR_WRITE_4(sc, SIS_RXFILT_CTL, filter | SIS_RXFILTCTL_ENABLE);
834 	CSR_READ_4(sc, SIS_RXFILT_CTL);
835 }
836 
837 static void
838 sis_reset(struct sis_softc *sc)
839 {
840 	int		i;
841 
842 	SIS_SETBIT(sc, SIS_CSR, SIS_CSR_RESET);
843 
844 	for (i = 0; i < SIS_TIMEOUT; i++) {
845 		if (!(CSR_READ_4(sc, SIS_CSR) & SIS_CSR_RESET))
846 			break;
847 	}
848 
849 	if (i == SIS_TIMEOUT)
850 		device_printf(sc->sis_dev, "reset never completed\n");
851 
852 	/* Wait a little while for the chip to get its brains in order. */
853 	DELAY(1000);
854 
855 	/*
856 	 * If this is a NetSemi chip, make sure to clear
857 	 * PME mode.
858 	 */
859 	if (sc->sis_type == SIS_TYPE_83815) {
860 		CSR_WRITE_4(sc, NS_CLKRUN, NS_CLKRUN_PMESTS);
861 		CSR_WRITE_4(sc, NS_CLKRUN, 0);
862 	} else {
863 		/* Disable WOL functions. */
864 		CSR_WRITE_4(sc, SIS_PWRMAN_CTL, 0);
865 	}
866 }
867 
868 /*
869  * Probe for an SiS chip. Check the PCI vendor and device
870  * IDs against our list and return a device name if we find a match.
871  */
872 static int
873 sis_probe(device_t dev)
874 {
875 	const struct sis_type	*t;
876 
877 	t = sis_devs;
878 
879 	while (t->sis_name != NULL) {
880 		if ((pci_get_vendor(dev) == t->sis_vid) &&
881 		    (pci_get_device(dev) == t->sis_did)) {
882 			device_set_desc(dev, t->sis_name);
883 			return (BUS_PROBE_DEFAULT);
884 		}
885 		t++;
886 	}
887 
888 	return (ENXIO);
889 }
890 
891 /*
892  * Attach the interface. Allocate softc structures, do ifmedia
893  * setup and ethernet/BPF attach.
894  */
895 static int
896 sis_attach(device_t dev)
897 {
898 	u_char			eaddr[ETHER_ADDR_LEN];
899 	struct sis_softc	*sc;
900 	if_t			ifp;
901 	int			error = 0, pmc;
902 
903 	sc = device_get_softc(dev);
904 
905 	sc->sis_dev = dev;
906 
907 	mtx_init(&sc->sis_mtx, device_get_nameunit(dev), MTX_NETWORK_LOCK,
908 	    MTX_DEF);
909 	callout_init_mtx(&sc->sis_stat_ch, &sc->sis_mtx, 0);
910 
911 	if (pci_get_device(dev) == SIS_DEVICEID_900)
912 		sc->sis_type = SIS_TYPE_900;
913 	if (pci_get_device(dev) == SIS_DEVICEID_7016)
914 		sc->sis_type = SIS_TYPE_7016;
915 	if (pci_get_vendor(dev) == NS_VENDORID)
916 		sc->sis_type = SIS_TYPE_83815;
917 
918 	sc->sis_rev = pci_read_config(dev, PCIR_REVID, 1);
919 	/*
920 	 * Map control/status registers.
921 	 */
922 	pci_enable_busmaster(dev);
923 
924 	error = bus_alloc_resources(dev, sis_res_spec, sc->sis_res);
925 	if (error) {
926 		device_printf(dev, "couldn't allocate resources\n");
927 		goto fail;
928 	}
929 
930 	/* Reset the adapter. */
931 	sis_reset(sc);
932 
933 	if (sc->sis_type == SIS_TYPE_900 &&
934 	    (sc->sis_rev == SIS_REV_635 ||
935 	    sc->sis_rev == SIS_REV_900B)) {
936 		SIO_SET(SIS_CFG_RND_CNT);
937 		SIO_SET(SIS_CFG_PERR_DETECT);
938 	}
939 
940 	/*
941 	 * Get station address from the EEPROM.
942 	 */
943 	switch (pci_get_vendor(dev)) {
944 	case NS_VENDORID:
945 		sc->sis_srr = CSR_READ_4(sc, NS_SRR);
946 
947 		/* We can't update the device description, so spew */
948 		if (sc->sis_srr == NS_SRR_15C)
949 			device_printf(dev, "Silicon Revision: DP83815C\n");
950 		else if (sc->sis_srr == NS_SRR_15D)
951 			device_printf(dev, "Silicon Revision: DP83815D\n");
952 		else if (sc->sis_srr == NS_SRR_16A)
953 			device_printf(dev, "Silicon Revision: DP83816A\n");
954 		else
955 			device_printf(dev, "Silicon Revision %x\n", sc->sis_srr);
956 
957 		/*
958 		 * Reading the MAC address out of the EEPROM on
959 		 * the NatSemi chip takes a bit more work than
960 		 * you'd expect. The address spans 4 16-bit words,
961 		 * with the first word containing only a single bit.
962 		 * You have to shift everything over one bit to
963 		 * get it aligned properly. Also, the bits are
964 		 * stored backwards (the LSB is really the MSB,
965 		 * and so on) so you have to reverse them in order
966 		 * to get the MAC address into the form we want.
967 		 * Why? Who the hell knows.
968 		 */
969 		{
970 			uint16_t		tmp[4];
971 
972 			sis_read_eeprom(sc, (caddr_t)&tmp,
973 			    NS_EE_NODEADDR, 4, 0);
974 
975 			/* Shift everything over one bit. */
976 			tmp[3] = tmp[3] >> 1;
977 			tmp[3] |= tmp[2] << 15;
978 			tmp[2] = tmp[2] >> 1;
979 			tmp[2] |= tmp[1] << 15;
980 			tmp[1] = tmp[1] >> 1;
981 			tmp[1] |= tmp[0] << 15;
982 
983 			/* Now reverse all the bits. */
984 			tmp[3] = sis_reverse(tmp[3]);
985 			tmp[2] = sis_reverse(tmp[2]);
986 			tmp[1] = sis_reverse(tmp[1]);
987 
988 			eaddr[0] = (tmp[1] >> 0) & 0xFF;
989 			eaddr[1] = (tmp[1] >> 8) & 0xFF;
990 			eaddr[2] = (tmp[2] >> 0) & 0xFF;
991 			eaddr[3] = (tmp[2] >> 8) & 0xFF;
992 			eaddr[4] = (tmp[3] >> 0) & 0xFF;
993 			eaddr[5] = (tmp[3] >> 8) & 0xFF;
994 		}
995 		break;
996 	case SIS_VENDORID:
997 	default:
998 #if defined(__i386__) || defined(__amd64__)
999 		/*
1000 		 * If this is a SiS 630E chipset with an embedded
1001 		 * SiS 900 controller, we have to read the MAC address
1002 		 * from the APC CMOS RAM. Our method for doing this
1003 		 * is very ugly since we have to reach out and grab
1004 		 * ahold of hardware for which we cannot properly
1005 		 * allocate resources. This code is only compiled on
1006 		 * the i386 architecture since the SiS 630E chipset
1007 		 * is for x86 motherboards only. Note that there are
1008 		 * a lot of magic numbers in this hack. These are
1009 		 * taken from SiS's Linux driver. I'd like to replace
1010 		 * them with proper symbolic definitions, but that
1011 		 * requires some datasheets that I don't have access
1012 		 * to at the moment.
1013 		 */
1014 		if (sc->sis_rev == SIS_REV_630S ||
1015 		    sc->sis_rev == SIS_REV_630E ||
1016 		    sc->sis_rev == SIS_REV_630EA1)
1017 			sis_read_cmos(sc, dev, (caddr_t)&eaddr, 0x9, 6);
1018 
1019 		else if (sc->sis_rev == SIS_REV_635 ||
1020 			 sc->sis_rev == SIS_REV_630ET)
1021 			sis_read_mac(sc, dev, (caddr_t)&eaddr);
1022 		else if (sc->sis_rev == SIS_REV_96x) {
1023 			/* Allow to read EEPROM from LAN. It is shared
1024 			 * between a 1394 controller and the NIC and each
1025 			 * time we access it, we need to set SIS_EECMD_REQ.
1026 			 */
1027 			SIO_SET(SIS_EECMD_REQ);
1028 			for (int waittime = 0; waittime < SIS_TIMEOUT;
1029 			    waittime++) {
1030 				/* Force EEPROM to idle state. */
1031 				sis_eeprom_idle(sc);
1032 				if (CSR_READ_4(sc, SIS_EECTL) & SIS_EECMD_GNT) {
1033 					sis_read_eeprom(sc, (caddr_t)&eaddr,
1034 					    SIS_EE_NODEADDR, 3, 0);
1035 					break;
1036 				}
1037 				DELAY(1);
1038 			}
1039 			/*
1040 			 * Set SIS_EECTL_CLK to high, so a other master
1041 			 * can operate on the i2c bus.
1042 			 */
1043 			SIO_SET(SIS_EECTL_CLK);
1044 			/* Refuse EEPROM access by LAN */
1045 			SIO_SET(SIS_EECMD_DONE);
1046 		} else
1047 #endif
1048 			sis_read_eeprom(sc, (caddr_t)&eaddr,
1049 			    SIS_EE_NODEADDR, 3, 0);
1050 		break;
1051 	}
1052 
1053 	sis_add_sysctls(sc);
1054 
1055 	/* Allocate DMA'able memory. */
1056 	if ((error = sis_dma_alloc(sc)) != 0)
1057 		goto fail;
1058 
1059 	ifp = sc->sis_ifp = if_alloc(IFT_ETHER);
1060 	if_setsoftc(ifp, sc);
1061 	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
1062 	if_setflags(ifp, IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST);
1063 	if_setioctlfn(ifp, sis_ioctl);
1064 	if_setstartfn(ifp, sis_start);
1065 	if_setinitfn(ifp, sis_init);
1066 	if_setsendqlen(ifp, SIS_TX_LIST_CNT - 1);
1067 	if_setsendqready(ifp);
1068 
1069 	if (pci_find_cap(sc->sis_dev, PCIY_PMG, &pmc) == 0) {
1070 		if (sc->sis_type == SIS_TYPE_83815)
1071 			if_setcapabilitiesbit(ifp, IFCAP_WOL, 0);
1072 		else
1073 			if_setcapabilitiesbit(ifp, IFCAP_WOL_MAGIC, 0);
1074 		if_setcapenable(ifp, if_getcapabilities(ifp));
1075 	}
1076 
1077 	/*
1078 	 * Do MII setup.
1079 	 */
1080 	error = mii_attach(dev, &sc->sis_miibus, ifp, sis_ifmedia_upd,
1081 	    sis_ifmedia_sts, BMSR_DEFCAPMASK, MII_PHY_ANY, MII_OFFSET_ANY, 0);
1082 	if (error != 0) {
1083 		device_printf(dev, "attaching PHYs failed\n");
1084 		goto fail;
1085 	}
1086 
1087 	/*
1088 	 * Call MI attach routine.
1089 	 */
1090 	ether_ifattach(ifp, eaddr);
1091 
1092 	/*
1093 	 * Tell the upper layer(s) we support long frames.
1094 	 */
1095 	if_setifheaderlen(ifp, sizeof(struct ether_vlan_header));
1096 	if_setcapabilitiesbit(ifp, IFCAP_VLAN_MTU, 0);
1097 	if_setcapenable(ifp, if_getcapabilities(ifp));
1098 #ifdef DEVICE_POLLING
1099 	if_setcapabilitiesbit(ifp, IFCAP_POLLING, 0);
1100 #endif
1101 
1102 	/* Hook interrupt last to avoid having to lock softc */
1103 	error = bus_setup_intr(dev, sc->sis_res[1], INTR_TYPE_NET | INTR_MPSAFE,
1104 	    NULL, sis_intr, sc, &sc->sis_intrhand);
1105 
1106 	if (error) {
1107 		device_printf(dev, "couldn't set up irq\n");
1108 		ether_ifdetach(ifp);
1109 		goto fail;
1110 	}
1111 
1112 fail:
1113 	if (error)
1114 		sis_detach(dev);
1115 
1116 	return (error);
1117 }
1118 
1119 /*
1120  * Shutdown hardware and free up resources. This can be called any
1121  * time after the mutex has been initialized. It is called in both
1122  * the error case in attach and the normal detach case so it needs
1123  * to be careful about only freeing resources that have actually been
1124  * allocated.
1125  */
1126 static int
1127 sis_detach(device_t dev)
1128 {
1129 	struct sis_softc	*sc;
1130 	if_t			ifp;
1131 
1132 	sc = device_get_softc(dev);
1133 	KASSERT(mtx_initialized(&sc->sis_mtx), ("sis mutex not initialized"));
1134 	ifp = sc->sis_ifp;
1135 
1136 #ifdef DEVICE_POLLING
1137 	if (if_getcapenable(ifp) & IFCAP_POLLING)
1138 		ether_poll_deregister(ifp);
1139 #endif
1140 
1141 	/* These should only be active if attach succeeded. */
1142 	if (device_is_attached(dev)) {
1143 		SIS_LOCK(sc);
1144 		sis_stop(sc);
1145 		SIS_UNLOCK(sc);
1146 		callout_drain(&sc->sis_stat_ch);
1147 		ether_ifdetach(ifp);
1148 	}
1149 	bus_generic_detach(dev);
1150 
1151 	if (sc->sis_intrhand)
1152 		bus_teardown_intr(dev, sc->sis_res[1], sc->sis_intrhand);
1153 	bus_release_resources(dev, sis_res_spec, sc->sis_res);
1154 
1155 	if (ifp)
1156 		if_free(ifp);
1157 
1158 	sis_dma_free(sc);
1159 
1160 	mtx_destroy(&sc->sis_mtx);
1161 
1162 	return (0);
1163 }
1164 
1165 struct sis_dmamap_arg {
1166 	bus_addr_t	sis_busaddr;
1167 };
1168 
1169 static void
1170 sis_dmamap_cb(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
1171 {
1172 	struct sis_dmamap_arg	*ctx;
1173 
1174 	if (error != 0)
1175 		return;
1176 
1177 	KASSERT(nsegs == 1, ("%s: %d segments returned!", __func__, nsegs));
1178 
1179 	ctx = (struct sis_dmamap_arg *)arg;
1180 	ctx->sis_busaddr = segs[0].ds_addr;
1181 }
1182 
1183 static int
1184 sis_dma_ring_alloc(struct sis_softc *sc, bus_size_t alignment,
1185     bus_size_t maxsize, bus_dma_tag_t *tag, uint8_t **ring, bus_dmamap_t *map,
1186     bus_addr_t *paddr, const char *msg)
1187 {
1188 	struct sis_dmamap_arg	ctx;
1189 	int			error;
1190 
1191 	error = bus_dma_tag_create(sc->sis_parent_tag, alignment, 0,
1192 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL, maxsize, 1,
1193 	    maxsize, 0, NULL, NULL, tag);
1194 	if (error != 0) {
1195 		device_printf(sc->sis_dev,
1196 		    "could not create %s dma tag\n", msg);
1197 		return (ENOMEM);
1198 	}
1199 	/* Allocate DMA'able memory for ring. */
1200 	error = bus_dmamem_alloc(*tag, (void **)ring,
1201 	    BUS_DMA_NOWAIT | BUS_DMA_ZERO | BUS_DMA_COHERENT, map);
1202 	if (error != 0) {
1203 		device_printf(sc->sis_dev,
1204 		    "could not allocate DMA'able memory for %s\n", msg);
1205 		return (ENOMEM);
1206 	}
1207 	/* Load the address of the ring. */
1208 	ctx.sis_busaddr = 0;
1209 	error = bus_dmamap_load(*tag, *map, *ring, maxsize, sis_dmamap_cb,
1210 	    &ctx, BUS_DMA_NOWAIT);
1211 	if (error != 0) {
1212 		device_printf(sc->sis_dev,
1213 		    "could not load DMA'able memory for %s\n", msg);
1214 		return (ENOMEM);
1215 	}
1216 	*paddr = ctx.sis_busaddr;
1217 	return (0);
1218 }
1219 
1220 static int
1221 sis_dma_alloc(struct sis_softc *sc)
1222 {
1223 	struct sis_rxdesc	*rxd;
1224 	struct sis_txdesc	*txd;
1225 	int			error, i;
1226 
1227 	/* Allocate the parent bus DMA tag appropriate for PCI. */
1228 	error = bus_dma_tag_create(bus_get_dma_tag(sc->sis_dev),
1229 	    1, 0, BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL,
1230 	    NULL, BUS_SPACE_MAXSIZE_32BIT, 0, BUS_SPACE_MAXSIZE_32BIT,
1231 	    0, NULL, NULL, &sc->sis_parent_tag);
1232 	if (error != 0) {
1233 		device_printf(sc->sis_dev,
1234 		    "could not allocate parent dma tag\n");
1235 		return (ENOMEM);
1236 	}
1237 
1238 	/* Create RX ring. */
1239 	error = sis_dma_ring_alloc(sc, SIS_DESC_ALIGN, SIS_RX_LIST_SZ,
1240 	    &sc->sis_rx_list_tag, (uint8_t **)&sc->sis_rx_list,
1241 	    &sc->sis_rx_list_map, &sc->sis_rx_paddr, "RX ring");
1242 	if (error)
1243 		return (error);
1244 
1245 	/* Create TX ring. */
1246 	error = sis_dma_ring_alloc(sc, SIS_DESC_ALIGN, SIS_TX_LIST_SZ,
1247 	    &sc->sis_tx_list_tag, (uint8_t **)&sc->sis_tx_list,
1248 	    &sc->sis_tx_list_map, &sc->sis_tx_paddr, "TX ring");
1249 	if (error)
1250 		return (error);
1251 
1252 	/* Create tag for RX mbufs. */
1253 	error = bus_dma_tag_create(sc->sis_parent_tag, SIS_RX_BUF_ALIGN, 0,
1254 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL, MCLBYTES, 1,
1255 	    MCLBYTES, 0, NULL, NULL, &sc->sis_rx_tag);
1256 	if (error) {
1257 		device_printf(sc->sis_dev, "could not allocate RX dma tag\n");
1258 		return (error);
1259 	}
1260 
1261 	/* Create tag for TX mbufs. */
1262 	error = bus_dma_tag_create(sc->sis_parent_tag, 1, 0,
1263 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
1264 	    MCLBYTES * SIS_MAXTXSEGS, SIS_MAXTXSEGS, MCLBYTES, 0, NULL, NULL,
1265 	    &sc->sis_tx_tag);
1266 	if (error) {
1267 		device_printf(sc->sis_dev, "could not allocate TX dma tag\n");
1268 		return (error);
1269 	}
1270 
1271 	/* Create DMA maps for RX buffers. */
1272 	error = bus_dmamap_create(sc->sis_rx_tag, 0, &sc->sis_rx_sparemap);
1273 	if (error) {
1274 		device_printf(sc->sis_dev,
1275 		    "can't create spare DMA map for RX\n");
1276 		return (error);
1277 	}
1278 	for (i = 0; i < SIS_RX_LIST_CNT; i++) {
1279 		rxd = &sc->sis_rxdesc[i];
1280 		rxd->rx_m = NULL;
1281 		error = bus_dmamap_create(sc->sis_rx_tag, 0, &rxd->rx_dmamap);
1282 		if (error) {
1283 			device_printf(sc->sis_dev,
1284 			    "can't create DMA map for RX\n");
1285 			return (error);
1286 		}
1287 	}
1288 
1289 	/* Create DMA maps for TX buffers. */
1290 	for (i = 0; i < SIS_TX_LIST_CNT; i++) {
1291 		txd = &sc->sis_txdesc[i];
1292 		txd->tx_m = NULL;
1293 		error = bus_dmamap_create(sc->sis_tx_tag, 0, &txd->tx_dmamap);
1294 		if (error) {
1295 			device_printf(sc->sis_dev,
1296 			    "can't create DMA map for TX\n");
1297 			return (error);
1298 		}
1299 	}
1300 
1301 	return (0);
1302 }
1303 
1304 static void
1305 sis_dma_free(struct sis_softc *sc)
1306 {
1307 	struct sis_rxdesc	*rxd;
1308 	struct sis_txdesc	*txd;
1309 	int			i;
1310 
1311 	/* Destroy DMA maps for RX buffers. */
1312 	for (i = 0; i < SIS_RX_LIST_CNT; i++) {
1313 		rxd = &sc->sis_rxdesc[i];
1314 		if (rxd->rx_dmamap)
1315 			bus_dmamap_destroy(sc->sis_rx_tag, rxd->rx_dmamap);
1316 	}
1317 	if (sc->sis_rx_sparemap)
1318 		bus_dmamap_destroy(sc->sis_rx_tag, sc->sis_rx_sparemap);
1319 
1320 	/* Destroy DMA maps for TX buffers. */
1321 	for (i = 0; i < SIS_TX_LIST_CNT; i++) {
1322 		txd = &sc->sis_txdesc[i];
1323 		if (txd->tx_dmamap)
1324 			bus_dmamap_destroy(sc->sis_tx_tag, txd->tx_dmamap);
1325 	}
1326 
1327 	if (sc->sis_rx_tag)
1328 		bus_dma_tag_destroy(sc->sis_rx_tag);
1329 	if (sc->sis_tx_tag)
1330 		bus_dma_tag_destroy(sc->sis_tx_tag);
1331 
1332 	/* Destroy RX ring. */
1333 	if (sc->sis_rx_paddr)
1334 		bus_dmamap_unload(sc->sis_rx_list_tag, sc->sis_rx_list_map);
1335 	if (sc->sis_rx_list)
1336 		bus_dmamem_free(sc->sis_rx_list_tag, sc->sis_rx_list,
1337 		    sc->sis_rx_list_map);
1338 
1339 	if (sc->sis_rx_list_tag)
1340 		bus_dma_tag_destroy(sc->sis_rx_list_tag);
1341 
1342 	/* Destroy TX ring. */
1343 	if (sc->sis_tx_paddr)
1344 		bus_dmamap_unload(sc->sis_tx_list_tag, sc->sis_tx_list_map);
1345 
1346 	if (sc->sis_tx_list)
1347 		bus_dmamem_free(sc->sis_tx_list_tag, sc->sis_tx_list,
1348 		    sc->sis_tx_list_map);
1349 
1350 	if (sc->sis_tx_list_tag)
1351 		bus_dma_tag_destroy(sc->sis_tx_list_tag);
1352 
1353 	/* Destroy the parent tag. */
1354 	if (sc->sis_parent_tag)
1355 		bus_dma_tag_destroy(sc->sis_parent_tag);
1356 }
1357 
1358 /*
1359  * Initialize the TX and RX descriptors and allocate mbufs for them. Note that
1360  * we arrange the descriptors in a closed ring, so that the last descriptor
1361  * points back to the first.
1362  */
1363 static int
1364 sis_ring_init(struct sis_softc *sc)
1365 {
1366 	struct sis_rxdesc	*rxd;
1367 	struct sis_txdesc	*txd;
1368 	bus_addr_t		next;
1369 	int			error, i;
1370 
1371 	bzero(&sc->sis_tx_list[0], SIS_TX_LIST_SZ);
1372 	for (i = 0; i < SIS_TX_LIST_CNT; i++) {
1373 		txd = &sc->sis_txdesc[i];
1374 		txd->tx_m = NULL;
1375 		if (i == SIS_TX_LIST_CNT - 1)
1376 			next = SIS_TX_RING_ADDR(sc, 0);
1377 		else
1378 			next = SIS_TX_RING_ADDR(sc, i + 1);
1379 		sc->sis_tx_list[i].sis_next = htole32(SIS_ADDR_LO(next));
1380 	}
1381 	sc->sis_tx_prod = sc->sis_tx_cons = sc->sis_tx_cnt = 0;
1382 	bus_dmamap_sync(sc->sis_tx_list_tag, sc->sis_tx_list_map,
1383 	    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1384 
1385 	sc->sis_rx_cons = 0;
1386 	bzero(&sc->sis_rx_list[0], SIS_RX_LIST_SZ);
1387 	for (i = 0; i < SIS_RX_LIST_CNT; i++) {
1388 		rxd = &sc->sis_rxdesc[i];
1389 		rxd->rx_desc = &sc->sis_rx_list[i];
1390 		if (i == SIS_RX_LIST_CNT - 1)
1391 			next = SIS_RX_RING_ADDR(sc, 0);
1392 		else
1393 			next = SIS_RX_RING_ADDR(sc, i + 1);
1394 		rxd->rx_desc->sis_next = htole32(SIS_ADDR_LO(next));
1395 		error = sis_newbuf(sc, rxd);
1396 		if (error)
1397 			return (error);
1398 	}
1399 	bus_dmamap_sync(sc->sis_rx_list_tag, sc->sis_rx_list_map,
1400 	    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1401 
1402 	return (0);
1403 }
1404 
1405 /*
1406  * Initialize an RX descriptor and attach an MBUF cluster.
1407  */
1408 static int
1409 sis_newbuf(struct sis_softc *sc, struct sis_rxdesc *rxd)
1410 {
1411 	struct mbuf		*m;
1412 	bus_dma_segment_t	segs[1];
1413 	bus_dmamap_t		map;
1414 	int nsegs;
1415 
1416 	m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
1417 	if (m == NULL)
1418 		return (ENOBUFS);
1419 	m->m_len = m->m_pkthdr.len = SIS_RXLEN;
1420 #ifndef __NO_STRICT_ALIGNMENT
1421 	m_adj(m, SIS_RX_BUF_ALIGN);
1422 #endif
1423 
1424 	if (bus_dmamap_load_mbuf_sg(sc->sis_rx_tag, sc->sis_rx_sparemap, m,
1425 	    segs, &nsegs, 0) != 0) {
1426 		m_freem(m);
1427 		return (ENOBUFS);
1428 	}
1429 	KASSERT(nsegs == 1, ("%s: %d segments returned!", __func__, nsegs));
1430 
1431 	if (rxd->rx_m != NULL) {
1432 		bus_dmamap_sync(sc->sis_rx_tag, rxd->rx_dmamap,
1433 		    BUS_DMASYNC_POSTREAD);
1434 		bus_dmamap_unload(sc->sis_rx_tag, rxd->rx_dmamap);
1435 	}
1436 	map = rxd->rx_dmamap;
1437 	rxd->rx_dmamap = sc->sis_rx_sparemap;
1438 	sc->sis_rx_sparemap = map;
1439 	bus_dmamap_sync(sc->sis_rx_tag, rxd->rx_dmamap, BUS_DMASYNC_PREREAD);
1440 	rxd->rx_m = m;
1441 	rxd->rx_desc->sis_ptr = htole32(SIS_ADDR_LO(segs[0].ds_addr));
1442 	rxd->rx_desc->sis_cmdsts = htole32(SIS_RXLEN);
1443 	return (0);
1444 }
1445 
1446 static __inline void
1447 sis_discard_rxbuf(struct sis_rxdesc *rxd)
1448 {
1449 
1450 	rxd->rx_desc->sis_cmdsts = htole32(SIS_RXLEN);
1451 }
1452 
1453 #ifndef __NO_STRICT_ALIGNMENT
1454 static __inline void
1455 sis_fixup_rx(struct mbuf *m)
1456 {
1457 	uint16_t		*src, *dst;
1458 	int			i;
1459 
1460 	src = mtod(m, uint16_t *);
1461 	dst = src - (SIS_RX_BUF_ALIGN - ETHER_ALIGN) / sizeof(*src);
1462 
1463 	for (i = 0; i < (m->m_len / sizeof(uint16_t) + 1); i++)
1464 		*dst++ = *src++;
1465 
1466 	m->m_data -= SIS_RX_BUF_ALIGN - ETHER_ALIGN;
1467 }
1468 #endif
1469 
1470 /*
1471  * A frame has been uploaded: pass the resulting mbuf chain up to
1472  * the higher level protocols.
1473  */
1474 static int
1475 sis_rxeof(struct sis_softc *sc)
1476 {
1477 	struct mbuf		*m;
1478 	if_t			ifp;
1479 	struct sis_rxdesc	*rxd;
1480 	struct sis_desc		*cur_rx;
1481 	int			prog, rx_cons, rx_npkts = 0, total_len;
1482 	uint32_t		rxstat;
1483 
1484 	SIS_LOCK_ASSERT(sc);
1485 
1486 	bus_dmamap_sync(sc->sis_rx_list_tag, sc->sis_rx_list_map,
1487 	    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
1488 
1489 	rx_cons = sc->sis_rx_cons;
1490 	ifp = sc->sis_ifp;
1491 
1492 	for (prog = 0; (if_getdrvflags(ifp) & IFF_DRV_RUNNING) != 0;
1493 	    SIS_INC(rx_cons, SIS_RX_LIST_CNT), prog++) {
1494 #ifdef DEVICE_POLLING
1495 		if (if_getcapenable(ifp) & IFCAP_POLLING) {
1496 			if (sc->rxcycles <= 0)
1497 				break;
1498 			sc->rxcycles--;
1499 		}
1500 #endif
1501 		cur_rx = &sc->sis_rx_list[rx_cons];
1502 		rxstat = le32toh(cur_rx->sis_cmdsts);
1503 		if ((rxstat & SIS_CMDSTS_OWN) == 0)
1504 			break;
1505 		rxd = &sc->sis_rxdesc[rx_cons];
1506 
1507 		total_len = (rxstat & SIS_CMDSTS_BUFLEN) - ETHER_CRC_LEN;
1508 		if ((if_getcapenable(ifp) & IFCAP_VLAN_MTU) != 0 &&
1509 		    total_len <= (ETHER_MAX_LEN + ETHER_VLAN_ENCAP_LEN -
1510 		    ETHER_CRC_LEN))
1511 			rxstat &= ~SIS_RXSTAT_GIANT;
1512 		if (SIS_RXSTAT_ERROR(rxstat) != 0) {
1513 			if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
1514 			if (rxstat & SIS_RXSTAT_COLL)
1515 				if_inc_counter(ifp, IFCOUNTER_COLLISIONS, 1);
1516 			sis_discard_rxbuf(rxd);
1517 			continue;
1518 		}
1519 
1520 		/* Add a new receive buffer to the ring. */
1521 		m = rxd->rx_m;
1522 		if (sis_newbuf(sc, rxd) != 0) {
1523 			if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1);
1524 			sis_discard_rxbuf(rxd);
1525 			continue;
1526 		}
1527 
1528 		/* No errors; receive the packet. */
1529 		m->m_pkthdr.len = m->m_len = total_len;
1530 #ifndef __NO_STRICT_ALIGNMENT
1531 		/*
1532 		 * On architectures without alignment problems we try to
1533 		 * allocate a new buffer for the receive ring, and pass up
1534 		 * the one where the packet is already, saving the expensive
1535 		 * copy operation.
1536 		 */
1537 		sis_fixup_rx(m);
1538 #endif
1539 		if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
1540 		m->m_pkthdr.rcvif = ifp;
1541 
1542 		SIS_UNLOCK(sc);
1543 		if_input(ifp, m);
1544 		SIS_LOCK(sc);
1545 		rx_npkts++;
1546 	}
1547 
1548 	if (prog > 0) {
1549 		sc->sis_rx_cons = rx_cons;
1550 		bus_dmamap_sync(sc->sis_rx_list_tag, sc->sis_rx_list_map,
1551 		    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1552 	}
1553 
1554 	return (rx_npkts);
1555 }
1556 
1557 /*
1558  * A frame was downloaded to the chip. It's safe for us to clean up
1559  * the list buffers.
1560  */
1561 
1562 static void
1563 sis_txeof(struct sis_softc *sc)
1564 {
1565 	if_t			ifp;
1566 	struct sis_desc		*cur_tx;
1567 	struct sis_txdesc	*txd;
1568 	uint32_t		cons, txstat;
1569 
1570 	SIS_LOCK_ASSERT(sc);
1571 
1572 	cons = sc->sis_tx_cons;
1573 	if (cons == sc->sis_tx_prod)
1574 		return;
1575 
1576 	ifp = sc->sis_ifp;
1577 	bus_dmamap_sync(sc->sis_tx_list_tag, sc->sis_tx_list_map,
1578 	    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
1579 
1580 	/*
1581 	 * Go through our tx list and free mbufs for those
1582 	 * frames that have been transmitted.
1583 	 */
1584 	for (; cons != sc->sis_tx_prod; SIS_INC(cons, SIS_TX_LIST_CNT)) {
1585 		cur_tx = &sc->sis_tx_list[cons];
1586 		txstat = le32toh(cur_tx->sis_cmdsts);
1587 		if ((txstat & SIS_CMDSTS_OWN) != 0)
1588 			break;
1589 		txd = &sc->sis_txdesc[cons];
1590 		if (txd->tx_m != NULL) {
1591 			bus_dmamap_sync(sc->sis_tx_tag, txd->tx_dmamap,
1592 			    BUS_DMASYNC_POSTWRITE);
1593 			bus_dmamap_unload(sc->sis_tx_tag, txd->tx_dmamap);
1594 			m_freem(txd->tx_m);
1595 			txd->tx_m = NULL;
1596 			if ((txstat & SIS_CMDSTS_PKT_OK) != 0) {
1597 				if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
1598 				if_inc_counter(ifp, IFCOUNTER_COLLISIONS,
1599 				    (txstat & SIS_TXSTAT_COLLCNT) >> 16);
1600 			} else {
1601 				if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
1602 				if (txstat & SIS_TXSTAT_EXCESSCOLLS)
1603 					if_inc_counter(ifp, IFCOUNTER_COLLISIONS, 1);
1604 				if (txstat & SIS_TXSTAT_OUTOFWINCOLL)
1605 					if_inc_counter(ifp, IFCOUNTER_COLLISIONS, 1);
1606 			}
1607 		}
1608 		sc->sis_tx_cnt--;
1609 		if_setdrvflagbits(ifp, 0, IFF_DRV_OACTIVE);
1610 	}
1611 	sc->sis_tx_cons = cons;
1612 	if (sc->sis_tx_cnt == 0)
1613 		sc->sis_watchdog_timer = 0;
1614 }
1615 
1616 static void
1617 sis_tick(void *xsc)
1618 {
1619 	struct sis_softc	*sc;
1620 	struct mii_data		*mii;
1621 
1622 	sc = xsc;
1623 	SIS_LOCK_ASSERT(sc);
1624 
1625 	mii = device_get_softc(sc->sis_miibus);
1626 	mii_tick(mii);
1627 	sis_watchdog(sc);
1628 	if ((sc->sis_flags & SIS_FLAG_LINK) == 0)
1629 		sis_miibus_statchg(sc->sis_dev);
1630 	callout_reset(&sc->sis_stat_ch, hz,  sis_tick, sc);
1631 }
1632 
1633 #ifdef DEVICE_POLLING
1634 static poll_handler_t sis_poll;
1635 
1636 static int
1637 sis_poll(if_t ifp, enum poll_cmd cmd, int count)
1638 {
1639 	struct	sis_softc *sc = if_getsoftc(ifp);
1640 	int rx_npkts = 0;
1641 
1642 	SIS_LOCK(sc);
1643 	if (!(if_getdrvflags(ifp) & IFF_DRV_RUNNING)) {
1644 		SIS_UNLOCK(sc);
1645 		return (rx_npkts);
1646 	}
1647 
1648 	/*
1649 	 * On the sis, reading the status register also clears it.
1650 	 * So before returning to intr mode we must make sure that all
1651 	 * possible pending sources of interrupts have been served.
1652 	 * In practice this means run to completion the *eof routines,
1653 	 * and then call the interrupt routine
1654 	 */
1655 	sc->rxcycles = count;
1656 	rx_npkts = sis_rxeof(sc);
1657 	sis_txeof(sc);
1658 	if (!if_sendq_empty(ifp))
1659 		sis_startl(ifp);
1660 
1661 	if (sc->rxcycles > 0 || cmd == POLL_AND_CHECK_STATUS) {
1662 		uint32_t	status;
1663 
1664 		/* Reading the ISR register clears all interrupts. */
1665 		status = CSR_READ_4(sc, SIS_ISR);
1666 
1667 		if (status & (SIS_ISR_RX_ERR|SIS_ISR_RX_OFLOW))
1668 			if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
1669 
1670 		if (status & (SIS_ISR_RX_IDLE))
1671 			SIS_SETBIT(sc, SIS_CSR, SIS_CSR_RX_ENABLE);
1672 
1673 		if (status & SIS_ISR_SYSERR) {
1674 			if_setdrvflagbits(ifp, 0, IFF_DRV_RUNNING);
1675 			sis_initl(sc);
1676 		}
1677 	}
1678 
1679 	SIS_UNLOCK(sc);
1680 	return (rx_npkts);
1681 }
1682 #endif /* DEVICE_POLLING */
1683 
1684 static void
1685 sis_intr(void *arg)
1686 {
1687 	struct sis_softc	*sc;
1688 	if_t			ifp;
1689 	uint32_t		status;
1690 
1691 	sc = arg;
1692 	ifp = sc->sis_ifp;
1693 
1694 	SIS_LOCK(sc);
1695 #ifdef DEVICE_POLLING
1696 	if (if_getcapenable(ifp) & IFCAP_POLLING) {
1697 		SIS_UNLOCK(sc);
1698 		return;
1699 	}
1700 #endif
1701 
1702 	/* Reading the ISR register clears all interrupts. */
1703 	status = CSR_READ_4(sc, SIS_ISR);
1704 	if ((status & SIS_INTRS) == 0) {
1705 		/* Not ours. */
1706 		SIS_UNLOCK(sc);
1707 		return;
1708 	}
1709 
1710 	/* Disable interrupts. */
1711 	CSR_WRITE_4(sc, SIS_IER, 0);
1712 
1713 	for (;(status & SIS_INTRS) != 0;) {
1714 		if ((if_getdrvflags(ifp) & IFF_DRV_RUNNING) == 0)
1715 			break;
1716 		if (status &
1717 		    (SIS_ISR_TX_DESC_OK | SIS_ISR_TX_ERR |
1718 		    SIS_ISR_TX_OK | SIS_ISR_TX_IDLE) )
1719 			sis_txeof(sc);
1720 
1721 		if (status & (SIS_ISR_RX_DESC_OK | SIS_ISR_RX_OK |
1722 		    SIS_ISR_RX_ERR | SIS_ISR_RX_IDLE))
1723 			sis_rxeof(sc);
1724 
1725 		if (status & SIS_ISR_RX_OFLOW)
1726 			if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
1727 
1728 		if (status & (SIS_ISR_RX_IDLE))
1729 			SIS_SETBIT(sc, SIS_CSR, SIS_CSR_RX_ENABLE);
1730 
1731 		if (status & SIS_ISR_SYSERR) {
1732 			if_setdrvflagbits(ifp, 0, IFF_DRV_RUNNING);
1733 			sis_initl(sc);
1734 			SIS_UNLOCK(sc);
1735 			return;
1736 		}
1737 		status = CSR_READ_4(sc, SIS_ISR);
1738 	}
1739 
1740 	if (if_getdrvflags(ifp) & IFF_DRV_RUNNING) {
1741 		/* Re-enable interrupts. */
1742 		CSR_WRITE_4(sc, SIS_IER, 1);
1743 
1744 		if (!if_sendq_empty(ifp))
1745 			sis_startl(ifp);
1746 	}
1747 
1748 	SIS_UNLOCK(sc);
1749 }
1750 
1751 /*
1752  * Encapsulate an mbuf chain in a descriptor by coupling the mbuf data
1753  * pointers to the fragment pointers.
1754  */
1755 static int
1756 sis_encap(struct sis_softc *sc, struct mbuf **m_head)
1757 {
1758 	struct mbuf		*m;
1759 	struct sis_txdesc	*txd;
1760 	struct sis_desc		*f;
1761 	bus_dma_segment_t	segs[SIS_MAXTXSEGS];
1762 	bus_dmamap_t		map;
1763 	int			error, i, frag, nsegs, prod;
1764 	int			padlen;
1765 
1766 	prod = sc->sis_tx_prod;
1767 	txd = &sc->sis_txdesc[prod];
1768 	if ((sc->sis_flags & SIS_FLAG_MANUAL_PAD) != 0 &&
1769 	    (*m_head)->m_pkthdr.len < SIS_MIN_FRAMELEN) {
1770 		m = *m_head;
1771 		padlen = SIS_MIN_FRAMELEN - m->m_pkthdr.len;
1772 		if (M_WRITABLE(m) == 0) {
1773 			/* Get a writable copy. */
1774 			m = m_dup(*m_head, M_NOWAIT);
1775 			m_freem(*m_head);
1776 			if (m == NULL) {
1777 				*m_head = NULL;
1778 				return (ENOBUFS);
1779 			}
1780 			*m_head = m;
1781 		}
1782 		if (m->m_next != NULL || M_TRAILINGSPACE(m) < padlen) {
1783 			m = m_defrag(m, M_NOWAIT);
1784 			if (m == NULL) {
1785 				m_freem(*m_head);
1786 				*m_head = NULL;
1787 				return (ENOBUFS);
1788 			}
1789 		}
1790 		/*
1791 		 * Manually pad short frames, and zero the pad space
1792 		 * to avoid leaking data.
1793 		 */
1794 		bzero(mtod(m, char *) + m->m_pkthdr.len, padlen);
1795 		m->m_pkthdr.len += padlen;
1796 		m->m_len = m->m_pkthdr.len;
1797 		*m_head = m;
1798 	}
1799 	error = bus_dmamap_load_mbuf_sg(sc->sis_tx_tag, txd->tx_dmamap,
1800 	    *m_head, segs, &nsegs, 0);
1801 	if (error == EFBIG) {
1802 		m = m_collapse(*m_head, M_NOWAIT, SIS_MAXTXSEGS);
1803 		if (m == NULL) {
1804 			m_freem(*m_head);
1805 			*m_head = NULL;
1806 			return (ENOBUFS);
1807 		}
1808 		*m_head = m;
1809 		error = bus_dmamap_load_mbuf_sg(sc->sis_tx_tag, txd->tx_dmamap,
1810 		    *m_head, segs, &nsegs, 0);
1811 		if (error != 0) {
1812 			m_freem(*m_head);
1813 			*m_head = NULL;
1814 			return (error);
1815 		}
1816 	} else if (error != 0)
1817 		return (error);
1818 
1819 	/* Check for descriptor overruns. */
1820 	if (sc->sis_tx_cnt + nsegs > SIS_TX_LIST_CNT - 1) {
1821 		bus_dmamap_unload(sc->sis_tx_tag, txd->tx_dmamap);
1822 		return (ENOBUFS);
1823 	}
1824 
1825 	bus_dmamap_sync(sc->sis_tx_tag, txd->tx_dmamap, BUS_DMASYNC_PREWRITE);
1826 
1827 	frag = prod;
1828 	for (i = 0; i < nsegs; i++) {
1829 		f = &sc->sis_tx_list[prod];
1830 		if (i == 0)
1831 			f->sis_cmdsts = htole32(segs[i].ds_len |
1832 			    SIS_CMDSTS_MORE);
1833 		else
1834 			f->sis_cmdsts = htole32(segs[i].ds_len |
1835 			    SIS_CMDSTS_OWN | SIS_CMDSTS_MORE);
1836 		f->sis_ptr = htole32(SIS_ADDR_LO(segs[i].ds_addr));
1837 		SIS_INC(prod, SIS_TX_LIST_CNT);
1838 		sc->sis_tx_cnt++;
1839 	}
1840 
1841 	/* Update producer index. */
1842 	sc->sis_tx_prod = prod;
1843 
1844 	/* Remove MORE flag on the last descriptor. */
1845 	prod = (prod - 1) & (SIS_TX_LIST_CNT - 1);
1846 	f = &sc->sis_tx_list[prod];
1847 	f->sis_cmdsts &= ~htole32(SIS_CMDSTS_MORE);
1848 
1849 	/* Lastly transfer ownership of packet to the controller. */
1850 	f = &sc->sis_tx_list[frag];
1851 	f->sis_cmdsts |= htole32(SIS_CMDSTS_OWN);
1852 
1853 	/* Swap the last and the first dmamaps. */
1854 	map = txd->tx_dmamap;
1855 	txd->tx_dmamap = sc->sis_txdesc[prod].tx_dmamap;
1856 	sc->sis_txdesc[prod].tx_dmamap = map;
1857 	sc->sis_txdesc[prod].tx_m = *m_head;
1858 
1859 	return (0);
1860 }
1861 
1862 static void
1863 sis_start(if_t ifp)
1864 {
1865 	struct sis_softc	*sc;
1866 
1867 	sc = if_getsoftc(ifp);
1868 	SIS_LOCK(sc);
1869 	sis_startl(ifp);
1870 	SIS_UNLOCK(sc);
1871 }
1872 
1873 static void
1874 sis_startl(if_t ifp)
1875 {
1876 	struct sis_softc	*sc;
1877 	struct mbuf		*m_head;
1878 	int			queued;
1879 
1880 	sc = if_getsoftc(ifp);
1881 
1882 	SIS_LOCK_ASSERT(sc);
1883 
1884 	if ((if_getdrvflags(ifp) & (IFF_DRV_RUNNING | IFF_DRV_OACTIVE)) !=
1885 	    IFF_DRV_RUNNING || (sc->sis_flags & SIS_FLAG_LINK) == 0)
1886 		return;
1887 
1888 	for (queued = 0; !if_sendq_empty(ifp) &&
1889 	    sc->sis_tx_cnt < SIS_TX_LIST_CNT - 4;) {
1890 		m_head = if_dequeue(ifp);
1891 		if (m_head == NULL)
1892 			break;
1893 
1894 		if (sis_encap(sc, &m_head) != 0) {
1895 			if (m_head == NULL)
1896 				break;
1897 			if_sendq_prepend(ifp, m_head);
1898 			if_setdrvflagbits(ifp, IFF_DRV_OACTIVE, 0);
1899 			break;
1900 		}
1901 
1902 		queued++;
1903 
1904 		/*
1905 		 * If there's a BPF listener, bounce a copy of this frame
1906 		 * to him.
1907 		 */
1908 		BPF_MTAP(ifp, m_head);
1909 	}
1910 
1911 	if (queued) {
1912 		/* Transmit */
1913 		bus_dmamap_sync(sc->sis_tx_list_tag, sc->sis_tx_list_map,
1914 		    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1915 		SIS_SETBIT(sc, SIS_CSR, SIS_CSR_TX_ENABLE);
1916 
1917 		/*
1918 		 * Set a timeout in case the chip goes out to lunch.
1919 		 */
1920 		sc->sis_watchdog_timer = 5;
1921 	}
1922 }
1923 
1924 static void
1925 sis_init(void *xsc)
1926 {
1927 	struct sis_softc	*sc = xsc;
1928 
1929 	SIS_LOCK(sc);
1930 	sis_initl(sc);
1931 	SIS_UNLOCK(sc);
1932 }
1933 
1934 static void
1935 sis_initl(struct sis_softc *sc)
1936 {
1937 	if_t			ifp = sc->sis_ifp;
1938 	struct mii_data		*mii;
1939 	uint8_t			*eaddr;
1940 
1941 	SIS_LOCK_ASSERT(sc);
1942 
1943 	if ((if_getdrvflags(ifp) & IFF_DRV_RUNNING) != 0)
1944 		return;
1945 
1946 	/*
1947 	 * Cancel pending I/O and free all RX/TX buffers.
1948 	 */
1949 	sis_stop(sc);
1950 	/*
1951 	 * Reset the chip to a known state.
1952 	 */
1953 	sis_reset(sc);
1954 #ifdef notyet
1955 	if (sc->sis_type == SIS_TYPE_83815 && sc->sis_srr >= NS_SRR_16A) {
1956 		/*
1957 		 * Configure 400usec of interrupt holdoff.  This is based
1958 		 * on empirical tests on a Soekris 4801.
1959  		 */
1960 		CSR_WRITE_4(sc, NS_IHR, 0x100 | 4);
1961 	}
1962 #endif
1963 
1964 	mii = device_get_softc(sc->sis_miibus);
1965 
1966 	/* Set MAC address */
1967 	eaddr = if_getlladdr(sc->sis_ifp);
1968 	if (sc->sis_type == SIS_TYPE_83815) {
1969 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, NS_FILTADDR_PAR0);
1970 		CSR_WRITE_4(sc, SIS_RXFILT_DATA, eaddr[0] | eaddr[1] << 8);
1971 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, NS_FILTADDR_PAR1);
1972 		CSR_WRITE_4(sc, SIS_RXFILT_DATA, eaddr[2] | eaddr[3] << 8);
1973 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, NS_FILTADDR_PAR2);
1974 		CSR_WRITE_4(sc, SIS_RXFILT_DATA, eaddr[4] | eaddr[5] << 8);
1975 	} else {
1976 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, SIS_FILTADDR_PAR0);
1977 		CSR_WRITE_4(sc, SIS_RXFILT_DATA, eaddr[0] | eaddr[1] << 8);
1978 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, SIS_FILTADDR_PAR1);
1979 		CSR_WRITE_4(sc, SIS_RXFILT_DATA, eaddr[2] | eaddr[3] << 8);
1980 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, SIS_FILTADDR_PAR2);
1981 		CSR_WRITE_4(sc, SIS_RXFILT_DATA, eaddr[4] | eaddr[5] << 8);
1982 	}
1983 
1984 	/* Init circular TX/RX lists. */
1985 	if (sis_ring_init(sc) != 0) {
1986 		device_printf(sc->sis_dev,
1987 		    "initialization failed: no memory for rx buffers\n");
1988 		sis_stop(sc);
1989 		return;
1990 	}
1991 
1992 	if (sc->sis_type == SIS_TYPE_83815) {
1993 		if (sc->sis_manual_pad != 0)
1994 			sc->sis_flags |= SIS_FLAG_MANUAL_PAD;
1995 		else
1996 			sc->sis_flags &= ~SIS_FLAG_MANUAL_PAD;
1997 	}
1998 
1999 	/*
2000 	 * Short Cable Receive Errors (MP21.E)
2001 	 * also: Page 78 of the DP83815 data sheet (september 2002 version)
2002 	 * recommends the following register settings "for optimum
2003 	 * performance." for rev 15C.  Set this also for 15D parts as
2004 	 * they require it in practice.
2005 	 */
2006 	if (sc->sis_type == SIS_TYPE_83815 && sc->sis_srr <= NS_SRR_15D) {
2007 		CSR_WRITE_4(sc, NS_PHY_PAGE, 0x0001);
2008 		CSR_WRITE_4(sc, NS_PHY_CR, 0x189C);
2009 		/* set val for c2 */
2010 		CSR_WRITE_4(sc, NS_PHY_TDATA, 0x0000);
2011 		/* load/kill c2 */
2012 		CSR_WRITE_4(sc, NS_PHY_DSPCFG, 0x5040);
2013 		/* rais SD off, from 4 to c */
2014 		CSR_WRITE_4(sc, NS_PHY_SDCFG, 0x008C);
2015 		CSR_WRITE_4(sc, NS_PHY_PAGE, 0);
2016 	}
2017 
2018 	sis_rxfilter(sc);
2019 
2020 	/*
2021 	 * Load the address of the RX and TX lists.
2022 	 */
2023 	CSR_WRITE_4(sc, SIS_RX_LISTPTR, SIS_ADDR_LO(sc->sis_rx_paddr));
2024 	CSR_WRITE_4(sc, SIS_TX_LISTPTR, SIS_ADDR_LO(sc->sis_tx_paddr));
2025 
2026 	/* SIS_CFG_EDB_MASTER_EN indicates the EDB bus is used instead of
2027 	 * the PCI bus. When this bit is set, the Max DMA Burst Size
2028 	 * for TX/RX DMA should be no larger than 16 double words.
2029 	 */
2030 	if (CSR_READ_4(sc, SIS_CFG) & SIS_CFG_EDB_MASTER_EN) {
2031 		CSR_WRITE_4(sc, SIS_RX_CFG, SIS_RXCFG64);
2032 	} else {
2033 		CSR_WRITE_4(sc, SIS_RX_CFG, SIS_RXCFG256);
2034 	}
2035 
2036 	/* Accept Long Packets for VLAN support */
2037 	SIS_SETBIT(sc, SIS_RX_CFG, SIS_RXCFG_RX_JABBER);
2038 
2039 	/*
2040 	 * Assume 100Mbps link, actual MAC configuration is done
2041 	 * after getting a valid link.
2042 	 */
2043 	CSR_WRITE_4(sc, SIS_TX_CFG, SIS_TXCFG_100);
2044 
2045 	/*
2046 	 * Enable interrupts.
2047 	 */
2048 	CSR_WRITE_4(sc, SIS_IMR, SIS_INTRS);
2049 #ifdef DEVICE_POLLING
2050 	/*
2051 	 * ... only enable interrupts if we are not polling, make sure
2052 	 * they are off otherwise.
2053 	 */
2054 	if (if_getcapenable(ifp) & IFCAP_POLLING)
2055 		CSR_WRITE_4(sc, SIS_IER, 0);
2056 	else
2057 #endif
2058 	CSR_WRITE_4(sc, SIS_IER, 1);
2059 
2060 	/* Clear MAC disable. */
2061 	SIS_CLRBIT(sc, SIS_CSR, SIS_CSR_TX_DISABLE | SIS_CSR_RX_DISABLE);
2062 
2063 	sc->sis_flags &= ~SIS_FLAG_LINK;
2064 	mii_mediachg(mii);
2065 
2066 	if_setdrvflagbits(ifp, IFF_DRV_RUNNING, 0);
2067 	if_setdrvflagbits(ifp, 0, IFF_DRV_OACTIVE);
2068 
2069 	callout_reset(&sc->sis_stat_ch, hz,  sis_tick, sc);
2070 }
2071 
2072 /*
2073  * Set media options.
2074  */
2075 static int
2076 sis_ifmedia_upd(if_t ifp)
2077 {
2078 	struct sis_softc	*sc;
2079 	struct mii_data		*mii;
2080 	struct mii_softc	*miisc;
2081 	int			error;
2082 
2083 	sc = if_getsoftc(ifp);
2084 
2085 	SIS_LOCK(sc);
2086 	mii = device_get_softc(sc->sis_miibus);
2087 	LIST_FOREACH(miisc, &mii->mii_phys, mii_list)
2088 		PHY_RESET(miisc);
2089 	error = mii_mediachg(mii);
2090 	SIS_UNLOCK(sc);
2091 
2092 	return (error);
2093 }
2094 
2095 /*
2096  * Report current media status.
2097  */
2098 static void
2099 sis_ifmedia_sts(if_t ifp, struct ifmediareq *ifmr)
2100 {
2101 	struct sis_softc	*sc;
2102 	struct mii_data		*mii;
2103 
2104 	sc = if_getsoftc(ifp);
2105 
2106 	SIS_LOCK(sc);
2107 	mii = device_get_softc(sc->sis_miibus);
2108 	mii_pollstat(mii);
2109 	ifmr->ifm_active = mii->mii_media_active;
2110 	ifmr->ifm_status = mii->mii_media_status;
2111 	SIS_UNLOCK(sc);
2112 }
2113 
2114 static int
2115 sis_ioctl(if_t ifp, u_long command, caddr_t data)
2116 {
2117 	struct sis_softc	*sc = if_getsoftc(ifp);
2118 	struct ifreq		*ifr = (struct ifreq *) data;
2119 	struct mii_data		*mii;
2120 	int			error = 0, mask;
2121 
2122 	switch (command) {
2123 	case SIOCSIFFLAGS:
2124 		SIS_LOCK(sc);
2125 		if (if_getflags(ifp) & IFF_UP) {
2126 			if ((if_getdrvflags(ifp) & IFF_DRV_RUNNING) != 0 &&
2127 			    ((if_getflags(ifp) ^ sc->sis_if_flags) &
2128 			    (IFF_PROMISC | IFF_ALLMULTI)) != 0)
2129 				sis_rxfilter(sc);
2130 			else
2131 				sis_initl(sc);
2132 		} else if (if_getdrvflags(ifp) & IFF_DRV_RUNNING)
2133 			sis_stop(sc);
2134 		sc->sis_if_flags = if_getflags(ifp);
2135 		SIS_UNLOCK(sc);
2136 		break;
2137 	case SIOCADDMULTI:
2138 	case SIOCDELMULTI:
2139 		SIS_LOCK(sc);
2140 		if ((if_getdrvflags(ifp) & IFF_DRV_RUNNING) != 0)
2141 			sis_rxfilter(sc);
2142 		SIS_UNLOCK(sc);
2143 		break;
2144 	case SIOCGIFMEDIA:
2145 	case SIOCSIFMEDIA:
2146 		mii = device_get_softc(sc->sis_miibus);
2147 		error = ifmedia_ioctl(ifp, ifr, &mii->mii_media, command);
2148 		break;
2149 	case SIOCSIFCAP:
2150 		SIS_LOCK(sc);
2151 		mask = ifr->ifr_reqcap ^ if_getcapenable(ifp);
2152 #ifdef DEVICE_POLLING
2153 		if ((mask & IFCAP_POLLING) != 0 &&
2154 		    (IFCAP_POLLING & if_getcapabilities(ifp)) != 0) {
2155 			if_togglecapenable(ifp, IFCAP_POLLING);
2156 			if ((IFCAP_POLLING & if_getcapenable(ifp)) != 0) {
2157 				error = ether_poll_register(sis_poll, ifp);
2158 				if (error != 0) {
2159 					SIS_UNLOCK(sc);
2160 					break;
2161 				}
2162 				/* Disable interrupts. */
2163 				CSR_WRITE_4(sc, SIS_IER, 0);
2164                         } else {
2165                                 error = ether_poll_deregister(ifp);
2166                                 /* Enable interrupts. */
2167 				CSR_WRITE_4(sc, SIS_IER, 1);
2168                         }
2169 		}
2170 #endif /* DEVICE_POLLING */
2171 		if ((mask & IFCAP_WOL) != 0 &&
2172 		    (if_getcapabilities(ifp) & IFCAP_WOL) != 0) {
2173 			if ((mask & IFCAP_WOL_UCAST) != 0)
2174 				if_togglecapenable(ifp, IFCAP_WOL_UCAST);
2175 			if ((mask & IFCAP_WOL_MCAST) != 0)
2176 				if_togglecapenable(ifp, IFCAP_WOL_MCAST);
2177 			if ((mask & IFCAP_WOL_MAGIC) != 0)
2178 				if_togglecapenable(ifp, IFCAP_WOL_MAGIC);
2179 		}
2180 		SIS_UNLOCK(sc);
2181 		break;
2182 	default:
2183 		error = ether_ioctl(ifp, command, data);
2184 		break;
2185 	}
2186 
2187 	return (error);
2188 }
2189 
2190 static void
2191 sis_watchdog(struct sis_softc *sc)
2192 {
2193 
2194 	SIS_LOCK_ASSERT(sc);
2195 
2196 	if (sc->sis_watchdog_timer == 0 || --sc->sis_watchdog_timer >0)
2197 		return;
2198 
2199 	device_printf(sc->sis_dev, "watchdog timeout\n");
2200 	if_inc_counter(sc->sis_ifp, IFCOUNTER_OERRORS, 1);
2201 
2202 	if_setdrvflagbits(sc->sis_ifp, 0, IFF_DRV_RUNNING);
2203 	sis_initl(sc);
2204 
2205 	if (!if_sendq_empty(sc->sis_ifp))
2206 		sis_startl(sc->sis_ifp);
2207 }
2208 
2209 /*
2210  * Stop the adapter and free any mbufs allocated to the
2211  * RX and TX lists.
2212  */
2213 static void
2214 sis_stop(struct sis_softc *sc)
2215 {
2216 	if_t			ifp;
2217 	struct sis_rxdesc *rxd;
2218 	struct sis_txdesc *txd;
2219 	int i;
2220 
2221 	SIS_LOCK_ASSERT(sc);
2222 
2223 	ifp = sc->sis_ifp;
2224 	sc->sis_watchdog_timer = 0;
2225 
2226 	callout_stop(&sc->sis_stat_ch);
2227 
2228 	if_setdrvflagbits(ifp, 0, (IFF_DRV_RUNNING | IFF_DRV_OACTIVE));
2229 	CSR_WRITE_4(sc, SIS_IER, 0);
2230 	CSR_WRITE_4(sc, SIS_IMR, 0);
2231 	CSR_READ_4(sc, SIS_ISR); /* clear any interrupts already pending */
2232 	SIS_SETBIT(sc, SIS_CSR, SIS_CSR_TX_DISABLE|SIS_CSR_RX_DISABLE);
2233 	DELAY(1000);
2234 	CSR_WRITE_4(sc, SIS_TX_LISTPTR, 0);
2235 	CSR_WRITE_4(sc, SIS_RX_LISTPTR, 0);
2236 
2237 	sc->sis_flags &= ~SIS_FLAG_LINK;
2238 
2239 	/*
2240 	 * Free data in the RX lists.
2241 	 */
2242 	for (i = 0; i < SIS_RX_LIST_CNT; i++) {
2243 		rxd = &sc->sis_rxdesc[i];
2244 		if (rxd->rx_m != NULL) {
2245 			bus_dmamap_sync(sc->sis_rx_tag, rxd->rx_dmamap,
2246 			    BUS_DMASYNC_POSTREAD);
2247 			bus_dmamap_unload(sc->sis_rx_tag, rxd->rx_dmamap);
2248 			m_freem(rxd->rx_m);
2249 			rxd->rx_m = NULL;
2250 		}
2251 	}
2252 
2253 	/*
2254 	 * Free the TX list buffers.
2255 	 */
2256 	for (i = 0; i < SIS_TX_LIST_CNT; i++) {
2257 		txd = &sc->sis_txdesc[i];
2258 		if (txd->tx_m != NULL) {
2259 			bus_dmamap_sync(sc->sis_tx_tag, txd->tx_dmamap,
2260 			    BUS_DMASYNC_POSTWRITE);
2261 			bus_dmamap_unload(sc->sis_tx_tag, txd->tx_dmamap);
2262 			m_freem(txd->tx_m);
2263 			txd->tx_m = NULL;
2264 		}
2265 	}
2266 }
2267 
2268 /*
2269  * Stop all chip I/O so that the kernel's probe routines don't
2270  * get confused by errant DMAs when rebooting.
2271  */
2272 static int
2273 sis_shutdown(device_t dev)
2274 {
2275 
2276 	return (sis_suspend(dev));
2277 }
2278 
2279 static int
2280 sis_suspend(device_t dev)
2281 {
2282 	struct sis_softc	*sc;
2283 
2284 	sc = device_get_softc(dev);
2285 	SIS_LOCK(sc);
2286 	sis_stop(sc);
2287 	sis_wol(sc);
2288 	SIS_UNLOCK(sc);
2289 	return (0);
2290 }
2291 
2292 static int
2293 sis_resume(device_t dev)
2294 {
2295 	struct sis_softc	*sc;
2296 	if_t			ifp;
2297 
2298 	sc = device_get_softc(dev);
2299 	SIS_LOCK(sc);
2300 	ifp = sc->sis_ifp;
2301 	if ((if_getflags(ifp) & IFF_UP) != 0) {
2302 		if_setdrvflagbits(ifp, 0, IFF_DRV_RUNNING);
2303 		sis_initl(sc);
2304 	}
2305 	SIS_UNLOCK(sc);
2306 	return (0);
2307 }
2308 
2309 static void
2310 sis_wol(struct sis_softc *sc)
2311 {
2312 	if_t			ifp;
2313 	uint32_t		val;
2314 	uint16_t		pmstat;
2315 	int			pmc;
2316 
2317 	ifp = sc->sis_ifp;
2318 	if ((if_getcapenable(ifp) & IFCAP_WOL) == 0)
2319 		return;
2320 
2321 	if (sc->sis_type == SIS_TYPE_83815) {
2322 		/* Reset RXDP. */
2323 		CSR_WRITE_4(sc, SIS_RX_LISTPTR, 0);
2324 
2325 		/* Configure WOL events. */
2326 		CSR_READ_4(sc, NS_WCSR);
2327 		val = 0;
2328 		if ((if_getcapenable(ifp) & IFCAP_WOL_UCAST) != 0)
2329 			val |= NS_WCSR_WAKE_UCAST;
2330 		if ((if_getcapenable(ifp) & IFCAP_WOL_MCAST) != 0)
2331 			val |= NS_WCSR_WAKE_MCAST;
2332 		if ((if_getcapenable(ifp) & IFCAP_WOL_MAGIC) != 0)
2333 			val |= NS_WCSR_WAKE_MAGIC;
2334 		CSR_WRITE_4(sc, NS_WCSR, val);
2335 		/* Enable PME and clear PMESTS. */
2336 		val = CSR_READ_4(sc, NS_CLKRUN);
2337 		val |= NS_CLKRUN_PMEENB | NS_CLKRUN_PMESTS;
2338 		CSR_WRITE_4(sc, NS_CLKRUN, val);
2339 		/* Enable silent RX mode. */
2340 		SIS_SETBIT(sc, SIS_CSR, SIS_CSR_RX_ENABLE);
2341 	} else {
2342 		if (pci_find_cap(sc->sis_dev, PCIY_PMG, &pmc) != 0)
2343 			return;
2344 		val = 0;
2345 		if ((if_getcapenable(ifp) & IFCAP_WOL_MAGIC) != 0)
2346 			val |= SIS_PWRMAN_WOL_MAGIC;
2347 		CSR_WRITE_4(sc, SIS_PWRMAN_CTL, val);
2348 		/* Request PME. */
2349 		pmstat = pci_read_config(sc->sis_dev,
2350 		    pmc + PCIR_POWER_STATUS, 2);
2351 		pmstat &= ~(PCIM_PSTAT_PME | PCIM_PSTAT_PMEENABLE);
2352 		if ((if_getcapenable(ifp) & IFCAP_WOL_MAGIC) != 0)
2353 			pmstat |= PCIM_PSTAT_PME | PCIM_PSTAT_PMEENABLE;
2354 		pci_write_config(sc->sis_dev,
2355 		    pmc + PCIR_POWER_STATUS, pmstat, 2);
2356 	}
2357 }
2358 
2359 static void
2360 sis_add_sysctls(struct sis_softc *sc)
2361 {
2362 	struct sysctl_ctx_list *ctx;
2363 	struct sysctl_oid_list *children;
2364 
2365 	ctx = device_get_sysctl_ctx(sc->sis_dev);
2366 	children = SYSCTL_CHILDREN(device_get_sysctl_tree(sc->sis_dev));
2367 
2368 	/*
2369 	 * Unlike most other controllers, NS DP83815/DP83816 controllers
2370 	 * seem to pad with 0xFF when it encounter short frames.  According
2371 	 * to RFC 1042 the pad bytes should be 0x00.  Turning this tunable
2372 	 * on will have driver pad manully but it's disabled by default
2373 	 * because it will consume extra CPU cycles for short frames.
2374 	 */
2375 	sc->sis_manual_pad = 0;
2376 	SYSCTL_ADD_INT(ctx, children, OID_AUTO, "manual_pad",
2377 	    CTLFLAG_RWTUN, &sc->sis_manual_pad, 0, "Manually pad short frames");
2378 }
2379 
2380 static device_method_t sis_methods[] = {
2381 	/* Device interface */
2382 	DEVMETHOD(device_probe,		sis_probe),
2383 	DEVMETHOD(device_attach,	sis_attach),
2384 	DEVMETHOD(device_detach,	sis_detach),
2385 	DEVMETHOD(device_shutdown,	sis_shutdown),
2386 	DEVMETHOD(device_suspend,	sis_suspend),
2387 	DEVMETHOD(device_resume,	sis_resume),
2388 
2389 	/* MII interface */
2390 	DEVMETHOD(miibus_readreg,	sis_miibus_readreg),
2391 	DEVMETHOD(miibus_writereg,	sis_miibus_writereg),
2392 	DEVMETHOD(miibus_statchg,	sis_miibus_statchg),
2393 
2394 	DEVMETHOD_END
2395 };
2396 
2397 static driver_t sis_driver = {
2398 	"sis",
2399 	sis_methods,
2400 	sizeof(struct sis_softc)
2401 };
2402 
2403 DRIVER_MODULE(sis, pci, sis_driver, 0, 0);
2404 DRIVER_MODULE(miibus, sis, miibus_driver, 0, 0);
2405