xref: /netbsd-src/sys/arch/powerpc/ibm4xx/dev/if_emac.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*	$NetBSD: if_emac.c,v 1.37 2010/04/05 07:19:31 joerg Exp $	*/
2 
3 /*
4  * Copyright 2001, 2002 Wasabi Systems, Inc.
5  * All rights reserved.
6  *
7  * Written by Simon Burge and Jason Thorpe for Wasabi Systems, Inc.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *      This product includes software developed for the NetBSD Project by
20  *      Wasabi Systems, Inc.
21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22  *    or promote products derived from this software without specific prior
23  *    written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 /*
39  * emac(4) supports following ibm4xx's EMACs.
40  *   XXXX: ZMII and 'TCP Accelaration Hardware' not support yet...
41  *
42  *            tested
43  *            ------
44  * 405EP	-  10/100 x2
45  * 405EX/EXr	o  10/100/1000 x2 (EXr x1), STA v2, 256bit hash-Table, RGMII
46  * 405GP/GPr	o  10/100
47  * 440EP	-  10/100 x2, ZMII
48  * 440GP	-  10/100 x2, ZMII
49  * 440GX	-  10/100/1000 x4, ZMII/RGMII(ch 2, 3), TAH(ch 2, 3)
50  * 440SP	-  10/100/1000
51  * 440SPe	-  10/100/1000, STA v2
52  */
53 
54 #include <sys/cdefs.h>
55 __KERNEL_RCSID(0, "$NetBSD: if_emac.c,v 1.37 2010/04/05 07:19:31 joerg Exp $");
56 
57 #include "opt_emac.h"
58 
59 #include <sys/param.h>
60 #include <sys/systm.h>
61 #include <sys/mbuf.h>
62 #include <sys/kernel.h>
63 #include <sys/socket.h>
64 #include <sys/ioctl.h>
65 
66 #include <uvm/uvm_extern.h>		/* for PAGE_SIZE */
67 
68 #include <net/if.h>
69 #include <net/if_dl.h>
70 #include <net/if_media.h>
71 #include <net/if_ether.h>
72 
73 #include <net/bpf.h>
74 
75 #include <powerpc/ibm4xx/dcr4xx.h>
76 #include <powerpc/ibm4xx/mal405gp.h>
77 #include <powerpc/ibm4xx/dev/emacreg.h>
78 #include <powerpc/ibm4xx/dev/if_emacreg.h>
79 #include <powerpc/ibm4xx/dev/if_emacvar.h>
80 #include <powerpc/ibm4xx/dev/malvar.h>
81 #include <powerpc/ibm4xx/dev/opbreg.h>
82 #include <powerpc/ibm4xx/dev/opbvar.h>
83 #include <powerpc/ibm4xx/dev/plbvar.h>
84 #if defined(EMAC_ZMII_PHY) || defined(EMAC_RGMII_PHY)
85 #include <powerpc/ibm4xx/dev/rmiivar.h>
86 #endif
87 
88 #include <dev/mii/miivar.h>
89 
90 #include "locators.h"
91 
92 
93 /*
94  * Transmit descriptor list size.  There are two Tx channels, each with
95  * up to 256 hardware descriptors available.  We currently use one Tx
96  * channel.  We tell the upper layers that they can queue a lot of
97  * packets, and we go ahead and manage up to 64 of them at a time.  We
98  * allow up to 16 DMA segments per packet.
99  */
100 #define	EMAC_NTXSEGS		16
101 #define	EMAC_TXQUEUELEN		64
102 #define	EMAC_TXQUEUELEN_MASK	(EMAC_TXQUEUELEN - 1)
103 #define	EMAC_TXQUEUE_GC		(EMAC_TXQUEUELEN / 4)
104 #define	EMAC_NTXDESC		256
105 #define	EMAC_NTXDESC_MASK	(EMAC_NTXDESC - 1)
106 #define	EMAC_NEXTTX(x)		(((x) + 1) & EMAC_NTXDESC_MASK)
107 #define	EMAC_NEXTTXS(x)		(((x) + 1) & EMAC_TXQUEUELEN_MASK)
108 
109 /*
110  * Receive descriptor list size.  There is one Rx channel with up to 256
111  * hardware descriptors available.  We allocate 64 receive descriptors,
112  * each with a 2k buffer (MCLBYTES).
113  */
114 #define	EMAC_NRXDESC		64
115 #define	EMAC_NRXDESC_MASK	(EMAC_NRXDESC - 1)
116 #define	EMAC_NEXTRX(x)		(((x) + 1) & EMAC_NRXDESC_MASK)
117 #define	EMAC_PREVRX(x)		(((x) - 1) & EMAC_NRXDESC_MASK)
118 
119 /*
120  * Transmit/receive descriptors that are DMA'd to the EMAC.
121  */
122 struct emac_control_data {
123 	struct mal_descriptor ecd_txdesc[EMAC_NTXDESC];
124 	struct mal_descriptor ecd_rxdesc[EMAC_NRXDESC];
125 };
126 
127 #define	EMAC_CDOFF(x)		offsetof(struct emac_control_data, x)
128 #define	EMAC_CDTXOFF(x)		EMAC_CDOFF(ecd_txdesc[(x)])
129 #define	EMAC_CDRXOFF(x)		EMAC_CDOFF(ecd_rxdesc[(x)])
130 
131 /*
132  * Software state for transmit jobs.
133  */
134 struct emac_txsoft {
135 	struct mbuf *txs_mbuf;		/* head of mbuf chain */
136 	bus_dmamap_t txs_dmamap;	/* our DMA map */
137 	int txs_firstdesc;		/* first descriptor in packet */
138 	int txs_lastdesc;		/* last descriptor in packet */
139 	int txs_ndesc;			/* # of descriptors used */
140 };
141 
142 /*
143  * Software state for receive descriptors.
144  */
145 struct emac_rxsoft {
146 	struct mbuf *rxs_mbuf;		/* head of mbuf chain */
147 	bus_dmamap_t rxs_dmamap;	/* our DMA map */
148 };
149 
150 /*
151  * Software state per device.
152  */
153 struct emac_softc {
154 	device_t sc_dev;		/* generic device information */
155 	int sc_instance;		/* instance no. */
156 	bus_space_tag_t sc_st;		/* bus space tag */
157 	bus_space_handle_t sc_sh;	/* bus space handle */
158 	bus_dma_tag_t sc_dmat;		/* bus DMA tag */
159 	struct ethercom sc_ethercom;	/* ethernet common data */
160 	void *sc_sdhook;		/* shutdown hook */
161 	void *sc_powerhook;		/* power management hook */
162 
163 	struct mii_data sc_mii;		/* MII/media information */
164 	struct callout sc_callout;	/* tick callout */
165 
166 	uint32_t sc_mr1;		/* copy of Mode Register 1 */
167 	uint32_t sc_stacr_read;		/* Read opcode of STAOPC of STACR */
168 	uint32_t sc_stacr_write;	/* Write opcode of STAOPC of STACR */
169 	uint32_t sc_stacr_bits;		/* misc bits of STACR */
170 	bool sc_stacr_completed;	/* Operation completed of STACR */
171 	int sc_htsize;			/* Hash Table size */
172 
173 	bus_dmamap_t sc_cddmamap;	/* control data dma map */
174 #define	sc_cddma	sc_cddmamap->dm_segs[0].ds_addr
175 
176 	/* Software state for transmit/receive descriptors. */
177 	struct emac_txsoft sc_txsoft[EMAC_TXQUEUELEN];
178 	struct emac_rxsoft sc_rxsoft[EMAC_NRXDESC];
179 
180 	/* Control data structures. */
181 	struct emac_control_data *sc_control_data;
182 #define	sc_txdescs	sc_control_data->ecd_txdesc
183 #define	sc_rxdescs	sc_control_data->ecd_rxdesc
184 
185 #ifdef EMAC_EVENT_COUNTERS
186 	struct evcnt sc_ev_rxintr;	/* Rx interrupts */
187 	struct evcnt sc_ev_txintr;	/* Tx interrupts */
188 	struct evcnt sc_ev_rxde;	/* Rx descriptor interrupts */
189 	struct evcnt sc_ev_txde;	/* Tx descriptor interrupts */
190 	struct evcnt sc_ev_intr;	/* General EMAC interrupts */
191 
192 	struct evcnt sc_ev_txreap;	/* Calls to Tx descriptor reaper */
193 	struct evcnt sc_ev_txsstall;	/* Tx stalled due to no txs */
194 	struct evcnt sc_ev_txdstall;	/* Tx stalled due to no txd */
195 	struct evcnt sc_ev_txdrop;	/* Tx packets dropped (too many segs) */
196 	struct evcnt sc_ev_tu;		/* Tx underrun */
197 #endif /* EMAC_EVENT_COUNTERS */
198 
199 	int sc_txfree;			/* number of free Tx descriptors */
200 	int sc_txnext;			/* next ready Tx descriptor */
201 
202 	int sc_txsfree;			/* number of free Tx jobs */
203 	int sc_txsnext;			/* next ready Tx job */
204 	int sc_txsdirty;		/* dirty Tx jobs */
205 
206 	int sc_rxptr;			/* next ready RX descriptor/descsoft */
207 
208 	void (*sc_rmii_enable)(device_t, int);		/* reduced MII enable */
209 	void (*sc_rmii_disable)(device_t, int);		/* reduced MII disable*/
210 	void (*sc_rmii_speed)(device_t, int, int);	/* reduced MII speed */
211 };
212 
213 #ifdef EMAC_EVENT_COUNTERS
214 #define	EMAC_EVCNT_INCR(ev)	(ev)->ev_count++
215 #else
216 #define	EMAC_EVCNT_INCR(ev)	/* nothing */
217 #endif
218 
219 #define	EMAC_CDTXADDR(sc, x)	((sc)->sc_cddma + EMAC_CDTXOFF((x)))
220 #define	EMAC_CDRXADDR(sc, x)	((sc)->sc_cddma + EMAC_CDRXOFF((x)))
221 
222 #define	EMAC_CDTXSYNC(sc, x, n, ops)					\
223 do {									\
224 	int __x, __n;							\
225 									\
226 	__x = (x);							\
227 	__n = (n);							\
228 									\
229 	/* If it will wrap around, sync to the end of the ring. */	\
230 	if ((__x + __n) > EMAC_NTXDESC) {				\
231 		bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,	\
232 		    EMAC_CDTXOFF(__x), sizeof(struct mal_descriptor) *	\
233 		    (EMAC_NTXDESC - __x), (ops));			\
234 		__n -= (EMAC_NTXDESC - __x);				\
235 		__x = 0;						\
236 	}								\
237 									\
238 	/* Now sync whatever is left. */				\
239 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
240 	    EMAC_CDTXOFF(__x), sizeof(struct mal_descriptor) * __n, (ops)); \
241 } while (/*CONSTCOND*/0)
242 
243 #define	EMAC_CDRXSYNC(sc, x, ops)					\
244 do {									\
245 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
246 	    EMAC_CDRXOFF((x)), sizeof(struct mal_descriptor), (ops));	\
247 } while (/*CONSTCOND*/0)
248 
249 #define	EMAC_INIT_RXDESC(sc, x)						\
250 do {									\
251 	struct emac_rxsoft *__rxs = &(sc)->sc_rxsoft[(x)];		\
252 	struct mal_descriptor *__rxd = &(sc)->sc_rxdescs[(x)];		\
253 	struct mbuf *__m = __rxs->rxs_mbuf;				\
254 									\
255 	/*								\
256 	 * Note: We scoot the packet forward 2 bytes in the buffer	\
257 	 * so that the payload after the Ethernet header is aligned	\
258 	 * to a 4-byte boundary.					\
259 	 */								\
260 	__m->m_data = __m->m_ext.ext_buf + 2;				\
261 									\
262 	__rxd->md_data = __rxs->rxs_dmamap->dm_segs[0].ds_addr + 2;	\
263 	__rxd->md_data_len = __m->m_ext.ext_size - 2;			\
264 	__rxd->md_stat_ctrl = MAL_RX_EMPTY | MAL_RX_INTERRUPT |		\
265 	    /* Set wrap on last descriptor. */				\
266 	    (((x) == EMAC_NRXDESC - 1) ? MAL_RX_WRAP : 0);		\
267 	EMAC_CDRXSYNC((sc), (x), BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE); \
268 } while (/*CONSTCOND*/0)
269 
270 #define	EMAC_WRITE(sc, reg, val) \
271 	bus_space_write_stream_4((sc)->sc_st, (sc)->sc_sh, (reg), (val))
272 #define	EMAC_READ(sc, reg) \
273 	bus_space_read_stream_4((sc)->sc_st, (sc)->sc_sh, (reg))
274 
275 #define	EMAC_SET_FILTER(aht, crc) \
276 do {									\
277 	(aht)[3 - (((crc) >> 26) >> 4)] |= 1 << (((crc) >> 26) & 0xf);	\
278 } while (/*CONSTCOND*/0)
279 #define	EMAC_SET_FILTER256(aht, crc) \
280 do {									\
281 	(aht)[7 - (((crc) >> 24) >> 5)] |= 1 << (((crc) >> 24) & 0x1f);	\
282 } while (/*CONSTCOND*/0)
283 
284 static int	emac_match(device_t, cfdata_t, void *);
285 static void	emac_attach(device_t, device_t, void *);
286 
287 static int	emac_intr(void *);
288 static void	emac_shutdown(void *);
289 
290 static void	emac_start(struct ifnet *);
291 static int	emac_ioctl(struct ifnet *, u_long, void *);
292 static int	emac_init(struct ifnet *);
293 static void	emac_stop(struct ifnet *, int);
294 static void	emac_watchdog(struct ifnet *);
295 
296 static int	emac_add_rxbuf(struct emac_softc *, int);
297 static void	emac_rxdrain(struct emac_softc *);
298 static int	emac_set_filter(struct emac_softc *);
299 static int	emac_txreap(struct emac_softc *);
300 
301 static void	emac_soft_reset(struct emac_softc *);
302 static void	emac_smart_reset(struct emac_softc *);
303 
304 static int	emac_mii_readreg(device_t, int, int);
305 static void	emac_mii_writereg(device_t, int, int, int);
306 static void	emac_mii_statchg(device_t);
307 static uint32_t	emac_mii_wait(struct emac_softc *);
308 static void	emac_mii_tick(void *);
309 
310 int		emac_copy_small = 0;
311 
312 CFATTACH_DECL_NEW(emac, sizeof(struct emac_softc),
313     emac_match, emac_attach, NULL, NULL);
314 
315 
316 static int
317 emac_match(device_t parent, cfdata_t cf, void *aux)
318 {
319 	struct opb_attach_args *oaa = aux;
320 
321 	/* match only on-chip ethernet devices */
322 	if (strcmp(oaa->opb_name, cf->cf_name) == 0)
323 		return 1;
324 
325 	return 0;
326 }
327 
328 static void
329 emac_attach(device_t parent, device_t self, void *aux)
330 {
331 	struct opb_attach_args *oaa = aux;
332 	struct emac_softc *sc = device_private(self);
333 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
334 	struct mii_data *mii = &sc->sc_mii;
335 	bus_dma_segment_t seg;
336 	int error, i, nseg, opb_freq, opbc, mii_phy = MII_PHY_ANY;
337 	const uint8_t *enaddr;
338 	prop_dictionary_t dict = device_properties(self);
339 	prop_data_t ea;
340 
341 	bus_space_map(oaa->opb_bt, oaa->opb_addr, EMAC_NREG, 0, &sc->sc_sh);
342 
343 	sc->sc_dev = self;
344 	sc->sc_instance = oaa->opb_instance;
345 	sc->sc_st = oaa->opb_bt;
346 	sc->sc_dmat = oaa->opb_dmat;
347 
348 	callout_init(&sc->sc_callout, 0);
349 
350 	aprint_naive("\n");
351 	aprint_normal(": Ethernet Media Access Controller\n");
352 
353 	/* Fetch the Ethernet address. */
354 	ea = prop_dictionary_get(dict, "mac-address");
355 	if (ea == NULL) {
356 		aprint_error_dev(self, "unable to get mac-address property\n");
357 		return;
358 	}
359 	KASSERT(prop_object_type(ea) == PROP_TYPE_DATA);
360 	KASSERT(prop_data_size(ea) == ETHER_ADDR_LEN);
361 	enaddr = prop_data_data_nocopy(ea);
362 	aprint_normal_dev(self, "Ethernet address %s\n", ether_sprintf(enaddr));
363 
364 #if defined(EMAC_ZMII_PHY) || defined(EMAC_RGMII_PHY)
365 	/* Fetch the MII offset. */
366 	prop_dictionary_get_uint32(dict, "mii-phy", &mii_phy);
367 
368 #ifdef EMAC_ZMII_PHY
369 	if (oaa->opb_flags & OPB_FLAGS_EMAC_RMII_ZMII)
370 		zmii_attach(parent, sc->sc_instance, &sc->sc_rmii_enable,
371 		    &sc->sc_rmii_disable, &sc->sc_rmii_speed);
372 #endif
373 #ifdef EMAC_RGMII_PHY
374 	if (oaa->opb_flags & OPB_FLAGS_EMAC_RMII_RGMII)
375 		rgmii_attach(parent, sc->sc_instance, &sc->sc_rmii_enable,
376 		    &sc->sc_rmii_disable, &sc->sc_rmii_speed);
377 #endif
378 #endif
379 
380 	/*
381 	 * Allocate the control data structures, and create and load the
382 	 * DMA map for it.
383 	 */
384 	if ((error = bus_dmamem_alloc(sc->sc_dmat,
385 	    sizeof(struct emac_control_data), 0, 0, &seg, 1, &nseg, 0)) != 0) {
386 		aprint_error_dev(self,
387 		    "unable to allocate control data, error = %d\n", error);
388 		goto fail_0;
389 	}
390 
391 	if ((error = bus_dmamem_map(sc->sc_dmat, &seg, nseg,
392 	    sizeof(struct emac_control_data), (void **)&sc->sc_control_data,
393 	    BUS_DMA_COHERENT)) != 0) {
394 		aprint_error_dev(self,
395 		    "unable to map control data, error = %d\n", error);
396 		goto fail_1;
397 	}
398 
399 	if ((error = bus_dmamap_create(sc->sc_dmat,
400 	    sizeof(struct emac_control_data), 1,
401 	    sizeof(struct emac_control_data), 0, 0, &sc->sc_cddmamap)) != 0) {
402 		aprint_error_dev(self,
403 		    "unable to create control data DMA map, error = %d\n",
404 		    error);
405 		goto fail_2;
406 	}
407 
408 	if ((error = bus_dmamap_load(sc->sc_dmat, sc->sc_cddmamap,
409 	    sc->sc_control_data, sizeof(struct emac_control_data), NULL,
410 	    0)) != 0) {
411 		aprint_error_dev(self,
412 		    "unable to load control data DMA map, error = %d\n", error);
413 		goto fail_3;
414 	}
415 
416 	/*
417 	 * Create the transmit buffer DMA maps.
418 	 */
419 	for (i = 0; i < EMAC_TXQUEUELEN; i++) {
420 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES,
421 		    EMAC_NTXSEGS, MCLBYTES, 0, 0,
422 		    &sc->sc_txsoft[i].txs_dmamap)) != 0) {
423 			aprint_error_dev(self,
424 			    "unable to create tx DMA map %d, error = %d\n",
425 			    i, error);
426 			goto fail_4;
427 		}
428 	}
429 
430 	/*
431 	 * Create the receive buffer DMA maps.
432 	 */
433 	for (i = 0; i < EMAC_NRXDESC; i++) {
434 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES, 1,
435 		    MCLBYTES, 0, 0, &sc->sc_rxsoft[i].rxs_dmamap)) != 0) {
436 			aprint_error_dev(self,
437 			    "unable to create rx DMA map %d, error = %d\n",
438 			    i, error);
439 			goto fail_5;
440 		}
441 		sc->sc_rxsoft[i].rxs_mbuf = NULL;
442 	}
443 
444 	/* Soft Reset the EMAC.  The chip to a known state. */
445 	emac_soft_reset(sc);
446 
447 	opb_freq = opb_get_frequency();
448 	switch (opb_freq) {
449 	case  50000000: opbc =  STACR_OPBC_50MHZ; break;
450 	case  66666666: opbc =  STACR_OPBC_66MHZ; break;
451 	case  83333333: opbc =  STACR_OPBC_83MHZ; break;
452 	case 100000000: opbc = STACR_OPBC_100MHZ; break;
453 
454 	default:
455 		if (opb_freq > 100000000) {
456 			opbc = STACR_OPBC_A100MHZ;
457 			break;
458 		}
459 		aprint_error_dev(self, "unsupport OPB frequency %dMHz\n",
460 		    opb_freq / 1000 / 1000);
461 		goto fail_5;
462 	}
463 	if (oaa->opb_flags & OPB_FLAGS_EMAC_GBE) {
464 		sc->sc_mr1 =
465 		    MR1_RFS_GBE(MR1__FS_16KB)	|
466 		    MR1_TFS_GBE(MR1__FS_16KB)	|
467 		    MR1_TR0_MULTIPLE		|
468 		    MR1_OBCI(opbc);
469 		sc->sc_ethercom.ec_capabilities |= ETHERCAP_JUMBO_MTU;
470 
471 		if (oaa->opb_flags & OPB_FLAGS_EMAC_STACV2) {
472 			sc->sc_stacr_read = STACR_STAOPC_READ;
473 			sc->sc_stacr_write = STACR_STAOPC_WRITE;
474 			sc->sc_stacr_bits = STACR_OC;
475 			sc->sc_stacr_completed = false;
476 		} else {
477 			sc->sc_stacr_read = STACR_READ;
478 			sc->sc_stacr_write = STACR_WRITE;
479 			sc->sc_stacr_completed = true;
480 		}
481 	} else {
482 		/*
483 		 * Set up Mode Register 1 - set receive and transmit FIFOs to
484 		 * maximum size, allow transmit of multiple packets (only
485 		 * channel 0 is used).
486 		 *
487 		 * XXX: Allow pause packets??
488 		 */
489 		sc->sc_mr1 =
490 		    MR1_RFS(MR1__FS_4KB) |
491 		    MR1_TFS(MR1__FS_2KB) |
492 		    MR1_TR0_MULTIPLE;
493 
494 		sc->sc_stacr_read = STACR_READ;
495 		sc->sc_stacr_write = STACR_WRITE;
496 		sc->sc_stacr_bits = STACR_OPBC(opbc);
497 		sc->sc_stacr_completed = true;
498 	}
499 
500 	intr_establish(oaa->opb_irq, IST_LEVEL, IPL_NET, emac_intr, sc);
501 	mal_intr_establish(sc->sc_instance, sc);
502 
503 	if (oaa->opb_flags & OPB_FLAGS_EMAC_HT256)
504 		sc->sc_htsize = 256;
505 	else
506 		sc->sc_htsize = 64;
507 
508 	/* Clear all interrupts */
509 	EMAC_WRITE(sc, EMAC_ISR, ISR_ALL);
510 
511 	/*
512 	 * Initialise the media structures.
513 	 */
514 	mii->mii_ifp = ifp;
515 	mii->mii_readreg = emac_mii_readreg;
516 	mii->mii_writereg = emac_mii_writereg;
517 	mii->mii_statchg = emac_mii_statchg;
518 
519 	sc->sc_ethercom.ec_mii = mii;
520 	ifmedia_init(&mii->mii_media, 0, ether_mediachange, ether_mediastatus);
521 	mii_attach(self, mii, 0xffffffff, mii_phy, MII_OFFSET_ANY, 0);
522 	if (LIST_FIRST(&mii->mii_phys) == NULL) {
523 		ifmedia_add(&mii->mii_media, IFM_ETHER|IFM_NONE, 0, NULL);
524 		ifmedia_set(&mii->mii_media, IFM_ETHER|IFM_NONE);
525 	} else
526 		ifmedia_set(&mii->mii_media, IFM_ETHER|IFM_AUTO);
527 
528 	ifp = &sc->sc_ethercom.ec_if;
529 	strcpy(ifp->if_xname, self->dv_xname);
530 	ifp->if_softc = sc;
531 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
532 	ifp->if_start = emac_start;
533 	ifp->if_ioctl = emac_ioctl;
534 	ifp->if_init = emac_init;
535 	ifp->if_stop = emac_stop;
536 	ifp->if_watchdog = emac_watchdog;
537 	IFQ_SET_READY(&ifp->if_snd);
538 
539 	/*
540 	 * We can support 802.1Q VLAN-sized frames.
541 	 */
542 	sc->sc_ethercom.ec_capabilities |= ETHERCAP_VLAN_MTU;
543 
544 	/*
545 	 * Attach the interface.
546 	 */
547 	if_attach(ifp);
548 	ether_ifattach(ifp, enaddr);
549 
550 #ifdef EMAC_EVENT_COUNTERS
551 	/*
552 	 * Attach the event counters.
553 	 */
554 	evcnt_attach_dynamic(&sc->sc_ev_txintr, EVCNT_TYPE_INTR,
555 	    NULL, self->dv_xname, "txintr");
556 	evcnt_attach_dynamic(&sc->sc_ev_rxintr, EVCNT_TYPE_INTR,
557 	    NULL, self->dv_xname, "rxintr");
558 	evcnt_attach_dynamic(&sc->sc_ev_txde, EVCNT_TYPE_INTR,
559 	    NULL, self->dv_xname, "txde");
560 	evcnt_attach_dynamic(&sc->sc_ev_rxde, EVCNT_TYPE_INTR,
561 	    NULL, self->dv_xname, "rxde");
562 	evcnt_attach_dynamic(&sc->sc_ev_intr, EVCNT_TYPE_INTR,
563 	    NULL, self->dv_xname, "intr");
564 
565 	evcnt_attach_dynamic(&sc->sc_ev_txreap, EVCNT_TYPE_MISC,
566 	    NULL, self->dv_xname, "txreap");
567 	evcnt_attach_dynamic(&sc->sc_ev_txsstall, EVCNT_TYPE_MISC,
568 	    NULL, self->dv_xname, "txsstall");
569 	evcnt_attach_dynamic(&sc->sc_ev_txdstall, EVCNT_TYPE_MISC,
570 	    NULL, self->dv_xname, "txdstall");
571 	evcnt_attach_dynamic(&sc->sc_ev_txdrop, EVCNT_TYPE_MISC,
572 	    NULL, self->dv_xname, "txdrop");
573 	evcnt_attach_dynamic(&sc->sc_ev_tu, EVCNT_TYPE_MISC,
574 	    NULL, self->dv_xname, "tu");
575 #endif /* EMAC_EVENT_COUNTERS */
576 
577 	/*
578 	 * Make sure the interface is shutdown during reboot.
579 	 */
580 	sc->sc_sdhook = shutdownhook_establish(emac_shutdown, sc);
581 	if (sc->sc_sdhook == NULL)
582 		aprint_error_dev(self,
583 		    "WARNING: unable to establish shutdown hook\n");
584 
585 	return;
586 
587 	/*
588 	 * Free any resources we've allocated during the failed attach
589 	 * attempt.  Do this in reverse order and fall through.
590 	 */
591 fail_5:
592 	for (i = 0; i < EMAC_NRXDESC; i++) {
593 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
594 			bus_dmamap_destroy(sc->sc_dmat,
595 			    sc->sc_rxsoft[i].rxs_dmamap);
596 	}
597 fail_4:
598 	for (i = 0; i < EMAC_TXQUEUELEN; i++) {
599 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
600 			bus_dmamap_destroy(sc->sc_dmat,
601 			    sc->sc_txsoft[i].txs_dmamap);
602 	}
603 	bus_dmamap_unload(sc->sc_dmat, sc->sc_cddmamap);
604 fail_3:
605 	bus_dmamap_destroy(sc->sc_dmat, sc->sc_cddmamap);
606 fail_2:
607 	bus_dmamem_unmap(sc->sc_dmat, (void *)sc->sc_control_data,
608 	    sizeof(struct emac_control_data));
609 fail_1:
610 	bus_dmamem_free(sc->sc_dmat, &seg, nseg);
611 fail_0:
612 	return;
613 }
614 
615 /*
616  * EMAC General interrupt handler
617  */
618 static int
619 emac_intr(void *arg)
620 {
621 	struct emac_softc *sc = arg;
622 	uint32_t status;
623 
624 	EMAC_EVCNT_INCR(&sc->sc_ev_intr);
625 	status = EMAC_READ(sc, EMAC_ISR);
626 
627 	/* Clear the interrupt status bits. */
628 	EMAC_WRITE(sc, EMAC_ISR, status);
629 
630 	return 1;
631 }
632 
633 static void
634 emac_shutdown(void *arg)
635 {
636 	struct emac_softc *sc = arg;
637 
638 	emac_stop(&sc->sc_ethercom.ec_if, 0);
639 }
640 
641 
642 /*
643  * ifnet interface functions
644  */
645 
646 static void
647 emac_start(struct ifnet *ifp)
648 {
649 	struct emac_softc *sc = ifp->if_softc;
650 	struct mbuf *m0;
651 	struct emac_txsoft *txs;
652 	bus_dmamap_t dmamap;
653 	int error, firsttx, nexttx, lasttx, ofree, seg;
654 
655 	lasttx = 0;	/* XXX gcc */
656 
657 	if ((ifp->if_flags & (IFF_RUNNING|IFF_OACTIVE)) != IFF_RUNNING)
658 		return;
659 
660 	/*
661 	 * Remember the previous number of free descriptors.
662 	 */
663 	ofree = sc->sc_txfree;
664 
665 	/*
666 	 * Loop through the send queue, setting up transmit descriptors
667 	 * until we drain the queue, or use up all available transmit
668 	 * descriptors.
669 	 */
670 	for (;;) {
671 		/* Grab a packet off the queue. */
672 		IFQ_POLL(&ifp->if_snd, m0);
673 		if (m0 == NULL)
674 			break;
675 
676 		/*
677 		 * Get a work queue entry.  Reclaim used Tx descriptors if
678 		 * we are running low.
679 		 */
680 		if (sc->sc_txsfree < EMAC_TXQUEUE_GC) {
681 			emac_txreap(sc);
682 			if (sc->sc_txsfree == 0) {
683 				EMAC_EVCNT_INCR(&sc->sc_ev_txsstall);
684 				break;
685 			}
686 		}
687 
688 		txs = &sc->sc_txsoft[sc->sc_txsnext];
689 		dmamap = txs->txs_dmamap;
690 
691 		/*
692 		 * Load the DMA map.  If this fails, the packet either
693 		 * didn't fit in the alloted number of segments, or we
694 		 * were short on resources.  In this case, we'll copy
695 		 * and try again.
696 		 */
697 		error = bus_dmamap_load_mbuf(sc->sc_dmat, dmamap, m0,
698 		    BUS_DMA_WRITE|BUS_DMA_NOWAIT);
699 		if (error) {
700 			if (error == EFBIG) {
701 				EMAC_EVCNT_INCR(&sc->sc_ev_txdrop);
702 				aprint_error_ifnet(ifp,
703 				    "Tx packet consumes too many "
704 				    "DMA segments, dropping...\n");
705 				    IFQ_DEQUEUE(&ifp->if_snd, m0);
706 				    m_freem(m0);
707 				    continue;
708 			}
709 			/* Short on resources, just stop for now. */
710 			break;
711 		}
712 
713 		/*
714 		 * Ensure we have enough descriptors free to describe
715 		 * the packet.
716 		 */
717 		if (dmamap->dm_nsegs > sc->sc_txfree) {
718 			/*
719 			 * Not enough free descriptors to transmit this
720 			 * packet.  We haven't committed anything yet,
721 			 * so just unload the DMA map, put the packet
722 			 * back on the queue, and punt.  Notify the upper
723 			 * layer that there are not more slots left.
724 			 *
725 			 */
726 			ifp->if_flags |= IFF_OACTIVE;
727 			bus_dmamap_unload(sc->sc_dmat, dmamap);
728 			EMAC_EVCNT_INCR(&sc->sc_ev_txdstall);
729 			break;
730 		}
731 
732 		IFQ_DEQUEUE(&ifp->if_snd, m0);
733 
734 		/*
735 		 * WE ARE NOW COMMITTED TO TRANSMITTING THE PACKET.
736 		 */
737 
738 		/* Sync the DMA map. */
739 		bus_dmamap_sync(sc->sc_dmat, dmamap, 0, dmamap->dm_mapsize,
740 		    BUS_DMASYNC_PREWRITE);
741 
742 		/*
743 		 * Store a pointer to the packet so that we can free it
744 		 * later.
745 		 */
746 		txs->txs_mbuf = m0;
747 		txs->txs_firstdesc = sc->sc_txnext;
748 		txs->txs_ndesc = dmamap->dm_nsegs;
749 
750 		/*
751 		 * Initialize the transmit descriptor.
752 		 */
753 		firsttx = sc->sc_txnext;
754 		for (nexttx = sc->sc_txnext, seg = 0;
755 		     seg < dmamap->dm_nsegs;
756 		     seg++, nexttx = EMAC_NEXTTX(nexttx)) {
757 			struct mal_descriptor *txdesc =
758 			    &sc->sc_txdescs[nexttx];
759 
760 			/*
761 			 * If this is the first descriptor we're
762 			 * enqueueing, don't set the TX_READY bit just
763 			 * yet.  That could cause a race condition.
764 			 * We'll do it below.
765 			 */
766 			txdesc->md_data = dmamap->dm_segs[seg].ds_addr;
767 			txdesc->md_data_len = dmamap->dm_segs[seg].ds_len;
768 			txdesc->md_stat_ctrl =
769 			    (txdesc->md_stat_ctrl & MAL_TX_WRAP) |
770 			    (nexttx == firsttx ? 0 : MAL_TX_READY) |
771 			    EMAC_TXC_GFCS | EMAC_TXC_GPAD;
772 			lasttx = nexttx;
773 		}
774 
775 		/* Set the LAST bit on the last segment. */
776 		sc->sc_txdescs[lasttx].md_stat_ctrl |= MAL_TX_LAST;
777 
778 		/*
779 		 * Set up last segment descriptor to send an interrupt after
780 		 * that descriptor is transmitted, and bypass existing Tx
781 		 * descriptor reaping method (for now...).
782 		 */
783 		sc->sc_txdescs[lasttx].md_stat_ctrl |= MAL_TX_INTERRUPT;
784 
785 
786 		txs->txs_lastdesc = lasttx;
787 
788 		/* Sync the descriptors we're using. */
789 		EMAC_CDTXSYNC(sc, sc->sc_txnext, dmamap->dm_nsegs,
790 		    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
791 
792 		/*
793 		 * The entire packet chain is set up.  Give the
794 		 * first descriptor to the chip now.
795 		 */
796 		sc->sc_txdescs[firsttx].md_stat_ctrl |= MAL_TX_READY;
797 		EMAC_CDTXSYNC(sc, firsttx, 1,
798 		    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
799 		/*
800 		 * Tell the EMAC that a new packet is available.
801 		 */
802 		EMAC_WRITE(sc, EMAC_TMR0, TMR0_GNP0 | TMR0_TFAE_2);
803 
804 		/* Advance the tx pointer. */
805 		sc->sc_txfree -= txs->txs_ndesc;
806 		sc->sc_txnext = nexttx;
807 
808 		sc->sc_txsfree--;
809 		sc->sc_txsnext = EMAC_NEXTTXS(sc->sc_txsnext);
810 
811 		/*
812 		 * Pass the packet to any BPF listeners.
813 		 */
814 		bpf_mtap(ifp, m0);
815 	}
816 
817 	if (sc->sc_txfree == 0)
818 		/* No more slots left; notify upper layer. */
819 		ifp->if_flags |= IFF_OACTIVE;
820 
821 	if (sc->sc_txfree != ofree)
822 		/* Set a watchdog timer in case the chip flakes out. */
823 		ifp->if_timer = 5;
824 }
825 
826 static int
827 emac_ioctl(struct ifnet *ifp, u_long cmd, void *data)
828 {
829 	struct emac_softc *sc = ifp->if_softc;
830 	int s, error;
831 
832 	s = splnet();
833 
834 	switch (cmd) {
835 	case SIOCSIFMTU:
836 	{
837 		struct ifreq *ifr = (struct ifreq *)data;
838 		int maxmtu;
839 
840 		if (sc->sc_ethercom.ec_capabilities & ETHERCAP_JUMBO_MTU)
841 			maxmtu = EMAC_MAX_MTU;
842 		else
843 			maxmtu = ETHERMTU;
844 
845 		if (ifr->ifr_mtu < ETHERMIN || ifr->ifr_mtu > maxmtu)
846 			error = EINVAL;
847 		else if ((error = ifioctl_common(ifp, cmd, data)) != ENETRESET)
848 			break;
849 		else if (ifp->if_flags & IFF_UP)
850 			error = emac_init(ifp);
851 		else
852 			error = 0;
853 		break;
854 	}
855 
856 	default:
857 		error = ether_ioctl(ifp, cmd, data);
858 		if (error == ENETRESET) {
859 			/*
860 			 * Multicast list has changed; set the hardware filter
861 			 * accordingly.
862 			 */
863 			if (ifp->if_flags & IFF_RUNNING)
864 				error = emac_set_filter(sc);
865 			else
866 				error = 0;
867 		}
868 	}
869 
870 	/* try to get more packets going */
871 	emac_start(ifp);
872 
873 	splx(s);
874 	return error;
875 }
876 
877 static int
878 emac_init(struct ifnet *ifp)
879 {
880 	struct emac_softc *sc = ifp->if_softc;
881 	struct emac_rxsoft *rxs;
882 	const uint8_t *enaddr = CLLADDR(ifp->if_sadl);
883 	int error, i;
884 
885 	error = 0;
886 
887 	/* Cancel any pending I/O. */
888 	emac_stop(ifp, 0);
889 
890 	/* Reset the chip to a known state. */
891 	emac_soft_reset(sc);
892 
893 	/*
894 	 * Initialise the transmit descriptor ring.
895 	 */
896 	memset(sc->sc_txdescs, 0, sizeof(sc->sc_txdescs));
897 	/* set wrap on last descriptor */
898 	sc->sc_txdescs[EMAC_NTXDESC - 1].md_stat_ctrl |= MAL_TX_WRAP;
899 	EMAC_CDTXSYNC(sc, 0, EMAC_NTXDESC,
900 	    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
901 	sc->sc_txfree = EMAC_NTXDESC;
902 	sc->sc_txnext = 0;
903 
904 	/*
905 	 * Initialise the transmit job descriptors.
906 	 */
907 	for (i = 0; i < EMAC_TXQUEUELEN; i++)
908 		sc->sc_txsoft[i].txs_mbuf = NULL;
909 	sc->sc_txsfree = EMAC_TXQUEUELEN;
910 	sc->sc_txsnext = 0;
911 	sc->sc_txsdirty = 0;
912 
913 	/*
914 	 * Initialise the receiver descriptor and receive job
915 	 * descriptor rings.
916 	 */
917 	for (i = 0; i < EMAC_NRXDESC; i++) {
918 		rxs = &sc->sc_rxsoft[i];
919 		if (rxs->rxs_mbuf == NULL) {
920 			if ((error = emac_add_rxbuf(sc, i)) != 0) {
921 				aprint_error_ifnet(ifp,
922 				    "unable to allocate or map rx buffer %d,"
923 				    " error = %d\n",
924 				    i, error);
925 				/*
926 				 * XXX Should attempt to run with fewer receive
927 				 * XXX buffers instead of just failing.
928 				 */
929 				emac_rxdrain(sc);
930 				goto out;
931 			}
932 		} else
933 			EMAC_INIT_RXDESC(sc, i);
934 	}
935 	sc->sc_rxptr = 0;
936 
937 	/*
938 	 * Set the current media.
939 	 */
940 	if ((error = ether_mediachange(ifp)) != 0)
941 		goto out;
942 
943 	/*
944 	 * Load the MAC address.
945 	 */
946 	EMAC_WRITE(sc, EMAC_IAHR, enaddr[0] << 8 | enaddr[1]);
947 	EMAC_WRITE(sc, EMAC_IALR,
948 	    enaddr[2] << 24 | enaddr[3] << 16 | enaddr[4] << 8 | enaddr[5]);
949 
950 	/* Enable the transmit and receive channel on the MAL. */
951 	error = mal_start(sc->sc_instance,
952 	    EMAC_CDTXADDR(sc, 0), EMAC_CDRXADDR(sc, 0));
953 	if (error)
954 		goto out;
955 
956 	sc->sc_mr1 &= ~MR1_JPSM;
957 	if (ifp->if_mtu > ETHERMTU)
958 		/* Enable Jumbo Packet Support Mode */
959 		sc->sc_mr1 |= MR1_JPSM;
960 
961 	/* Set fifos, media modes. */
962 	EMAC_WRITE(sc, EMAC_MR1, sc->sc_mr1);
963 
964 	/*
965 	 * Enable Individual and (possibly) Broadcast Address modes,
966 	 * runt packets, and strip padding.
967 	 */
968 	EMAC_WRITE(sc, EMAC_RMR, RMR_IAE | RMR_RRP | RMR_SP | RMR_TFAE_2 |
969 	    (ifp->if_flags & IFF_PROMISC ? RMR_PME : 0) |
970 	    (ifp->if_flags & IFF_BROADCAST ? RMR_BAE : 0));
971 
972 	/*
973 	 * Set multicast filter.
974 	 */
975 	emac_set_filter(sc);
976 
977 	/*
978 	 * Set low- and urgent-priority request thresholds.
979 	 */
980 	EMAC_WRITE(sc, EMAC_TMR1,
981 	    ((7 << TMR1_TLR_SHIFT) & TMR1_TLR_MASK) | /* 16 word burst */
982 	    ((15 << TMR1_TUR_SHIFT) & TMR1_TUR_MASK));
983 	/*
984 	 * Set Transmit Request Threshold Register.
985 	 */
986 	EMAC_WRITE(sc, EMAC_TRTR, TRTR_256);
987 
988 	/*
989 	 * Set high and low receive watermarks.
990 	 */
991 	EMAC_WRITE(sc, EMAC_RWMR,
992 	    30 << RWMR_RLWM_SHIFT | 64 << RWMR_RLWM_SHIFT);
993 
994 	/*
995 	 * Set frame gap.
996 	 */
997 	EMAC_WRITE(sc, EMAC_IPGVR, 8);
998 
999 	/*
1000 	 * Set interrupt status enable bits for EMAC.
1001 	 */
1002 	EMAC_WRITE(sc, EMAC_ISER,
1003 	    ISR_TXPE |		/* TX Parity Error */
1004 	    ISR_RXPE |		/* RX Parity Error */
1005 	    ISR_TXUE |		/* TX Underrun Event */
1006 	    ISR_RXOE |		/* RX Overrun Event */
1007 	    ISR_OVR  |		/* Overrun Error */
1008 	    ISR_PP   |		/* Pause Packet */
1009 	    ISR_BP   |		/* Bad Packet */
1010 	    ISR_RP   |		/* Runt Packet */
1011 	    ISR_SE   |		/* Short Event */
1012 	    ISR_ALE  |		/* Alignment Error */
1013 	    ISR_BFCS |		/* Bad FCS */
1014 	    ISR_PTLE |		/* Packet Too Long Error */
1015 	    ISR_ORE  |		/* Out of Range Error */
1016 	    ISR_IRE  |		/* In Range Error */
1017 	    ISR_SE0  |		/* Signal Quality Error 0 (SQE) */
1018 	    ISR_TE0  |		/* Transmit Error 0 */
1019 	    ISR_MOS  |		/* MMA Operation Succeeded */
1020 	    ISR_MOF);		/* MMA Operation Failed */
1021 
1022 	/*
1023 	 * Enable the transmit and receive channel on the EMAC.
1024 	 */
1025 	EMAC_WRITE(sc, EMAC_MR0, MR0_TXE | MR0_RXE);
1026 
1027 	/*
1028 	 * Start the one second MII clock.
1029 	 */
1030 	callout_reset(&sc->sc_callout, hz, emac_mii_tick, sc);
1031 
1032 	/*
1033 	 * ... all done!
1034 	 */
1035 	ifp->if_flags |= IFF_RUNNING;
1036 	ifp->if_flags &= ~IFF_OACTIVE;
1037 
1038  out:
1039 	if (error) {
1040 		ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
1041 		ifp->if_timer = 0;
1042 		aprint_error_ifnet(ifp, "interface not running\n");
1043 	}
1044 	return error;
1045 }
1046 
1047 static void
1048 emac_stop(struct ifnet *ifp, int disable)
1049 {
1050 	struct emac_softc *sc = ifp->if_softc;
1051 	struct emac_txsoft *txs;
1052 	int i;
1053 
1054 	/* Stop the one second clock. */
1055 	callout_stop(&sc->sc_callout);
1056 
1057 	/* Down the MII */
1058 	mii_down(&sc->sc_mii);
1059 
1060 	/* Disable interrupts. */
1061 	EMAC_WRITE(sc, EMAC_ISER, 0);
1062 
1063 	/* Disable the receive and transmit channels. */
1064 	mal_stop(sc->sc_instance);
1065 
1066 	/* Disable the transmit enable and receive MACs. */
1067 	EMAC_WRITE(sc, EMAC_MR0,
1068 	    EMAC_READ(sc, EMAC_MR0) & ~(MR0_TXE | MR0_RXE));
1069 
1070 	/* Release any queued transmit buffers. */
1071 	for (i = 0; i < EMAC_TXQUEUELEN; i++) {
1072 		txs = &sc->sc_txsoft[i];
1073 		if (txs->txs_mbuf != NULL) {
1074 			bus_dmamap_unload(sc->sc_dmat, txs->txs_dmamap);
1075 			m_freem(txs->txs_mbuf);
1076 			txs->txs_mbuf = NULL;
1077 		}
1078 	}
1079 
1080 	if (disable)
1081 		emac_rxdrain(sc);
1082 
1083 	/*
1084 	 * Mark the interface down and cancel the watchdog timer.
1085 	 */
1086 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
1087 	ifp->if_timer = 0;
1088 }
1089 
1090 static void
1091 emac_watchdog(struct ifnet *ifp)
1092 {
1093 	struct emac_softc *sc = ifp->if_softc;
1094 
1095 	/*
1096 	 * Since we're not interrupting every packet, sweep
1097 	 * up before we report an error.
1098 	 */
1099 	emac_txreap(sc);
1100 
1101 	if (sc->sc_txfree != EMAC_NTXDESC) {
1102 		aprint_error_ifnet(ifp,
1103 		    "device timeout (txfree %d txsfree %d txnext %d)\n",
1104 		    sc->sc_txfree, sc->sc_txsfree, sc->sc_txnext);
1105 		ifp->if_oerrors++;
1106 
1107 		/* Reset the interface. */
1108 		(void)emac_init(ifp);
1109 	} else if (ifp->if_flags & IFF_DEBUG)
1110 		aprint_error_ifnet(ifp, "recovered from device timeout\n");
1111 
1112 	/* try to get more packets going */
1113 	emac_start(ifp);
1114 }
1115 
1116 static int
1117 emac_add_rxbuf(struct emac_softc *sc, int idx)
1118 {
1119 	struct emac_rxsoft *rxs = &sc->sc_rxsoft[idx];
1120 	struct mbuf *m;
1121 	int error;
1122 
1123 	MGETHDR(m, M_DONTWAIT, MT_DATA);
1124 	if (m == NULL)
1125 		return ENOBUFS;
1126 
1127 	MCLGET(m, M_DONTWAIT);
1128 	if ((m->m_flags & M_EXT) == 0) {
1129 		m_freem(m);
1130 		return ENOBUFS;
1131 	}
1132 
1133 	if (rxs->rxs_mbuf != NULL)
1134 		bus_dmamap_unload(sc->sc_dmat, rxs->rxs_dmamap);
1135 
1136 	rxs->rxs_mbuf = m;
1137 
1138 	error = bus_dmamap_load(sc->sc_dmat, rxs->rxs_dmamap,
1139 	    m->m_ext.ext_buf, m->m_ext.ext_size, NULL, BUS_DMA_NOWAIT);
1140 	if (error) {
1141 		aprint_error_dev(sc->sc_dev,
1142 		    "can't load rx DMA map %d, error = %d\n", idx, error);
1143 		panic("emac_add_rxbuf");		/* XXX */
1144 	}
1145 
1146 	bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1147 	    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
1148 
1149 	EMAC_INIT_RXDESC(sc, idx);
1150 
1151 	return 0;
1152 }
1153 
1154 static void
1155 emac_rxdrain(struct emac_softc *sc)
1156 {
1157 	struct emac_rxsoft *rxs;
1158 	int i;
1159 
1160 	for (i = 0; i < EMAC_NRXDESC; i++) {
1161 		rxs = &sc->sc_rxsoft[i];
1162 		if (rxs->rxs_mbuf != NULL) {
1163 			bus_dmamap_unload(sc->sc_dmat, rxs->rxs_dmamap);
1164 			m_freem(rxs->rxs_mbuf);
1165 			rxs->rxs_mbuf = NULL;
1166 		}
1167 	}
1168 }
1169 
1170 static int
1171 emac_set_filter(struct emac_softc *sc)
1172 {
1173 	struct ether_multistep step;
1174 	struct ether_multi *enm;
1175 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1176 	uint32_t rmr, crc, mask, tmp, reg, gaht[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
1177 	int regs, cnt = 0, i;
1178 
1179 	if (sc->sc_htsize == 256) {
1180 		reg = EMAC_GAHT256(0);
1181 		regs = 8;
1182 	} else {
1183 		reg = EMAC_GAHT64(0);
1184 		regs = 4;
1185 	}
1186 	mask = (1ULL << (sc->sc_htsize / regs)) - 1;
1187 
1188 	rmr = EMAC_READ(sc, EMAC_RMR);
1189 	rmr &= ~(RMR_PMME | RMR_MAE);
1190 	ifp->if_flags &= ~IFF_ALLMULTI;
1191 
1192 	ETHER_FIRST_MULTI(step, &sc->sc_ethercom, enm);
1193 	while (enm != NULL) {
1194 		if (memcmp(enm->enm_addrlo,
1195 		    enm->enm_addrhi, ETHER_ADDR_LEN) != 0) {
1196 			/*
1197 			 * We must listen to a range of multicast addresses.
1198 			 * For now, just accept all multicasts, rather than
1199 			 * trying to set only those filter bits needed to match
1200 			 * the range.  (At this time, the only use of address
1201 			 * ranges is for IP multicast routing, for which the
1202 			 * range is big enough to require all bits set.)
1203 			 */
1204 			gaht[0] = gaht[1] = gaht[2] = gaht[3] =
1205 			    gaht[4] = gaht[5] = gaht[6] = gaht[7] = mask;
1206 			break;
1207 		}
1208 
1209 		crc = ether_crc32_be(enm->enm_addrlo, ETHER_ADDR_LEN);
1210 
1211 		if (sc->sc_htsize == 256)
1212 			EMAC_SET_FILTER256(gaht, crc);
1213 		else
1214 			EMAC_SET_FILTER(gaht, crc);
1215 
1216 		ETHER_NEXT_MULTI(step, enm);
1217 		cnt++;
1218 	}
1219 
1220 	for (i = 1, tmp = gaht[0]; i < regs; i++)
1221 		tmp &= gaht[i];
1222 	if (tmp == mask) {
1223 		/* All categories are true. */
1224 		ifp->if_flags |= IFF_ALLMULTI;
1225 		rmr |= RMR_PMME;
1226 	} else if (cnt != 0) {
1227 		/* Some categories are true. */
1228 		for (i = 0; i < regs; i++)
1229 			EMAC_WRITE(sc, reg + (i << 2), gaht[i]);
1230 		rmr |= RMR_MAE;
1231 	}
1232 	EMAC_WRITE(sc, EMAC_RMR, rmr);
1233 
1234 	return 0;
1235 }
1236 
1237 /*
1238  * Reap completed Tx descriptors.
1239  */
1240 static int
1241 emac_txreap(struct emac_softc *sc)
1242 {
1243 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1244 	struct emac_txsoft *txs;
1245 	int handled, i;
1246 	uint32_t txstat;
1247 
1248 	EMAC_EVCNT_INCR(&sc->sc_ev_txreap);
1249 	handled = 0;
1250 
1251 	ifp->if_flags &= ~IFF_OACTIVE;
1252 
1253 	/*
1254 	 * Go through our Tx list and free mbufs for those
1255 	 * frames that have been transmitted.
1256 	 */
1257 	for (i = sc->sc_txsdirty; sc->sc_txsfree != EMAC_TXQUEUELEN;
1258 	    i = EMAC_NEXTTXS(i), sc->sc_txsfree++) {
1259 		txs = &sc->sc_txsoft[i];
1260 
1261 		EMAC_CDTXSYNC(sc, txs->txs_lastdesc,
1262 		    txs->txs_dmamap->dm_nsegs,
1263 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1264 
1265 		txstat = sc->sc_txdescs[txs->txs_lastdesc].md_stat_ctrl;
1266 		if (txstat & MAL_TX_READY)
1267 			break;
1268 
1269 		handled = 1;
1270 
1271 		/*
1272 		 * Check for errors and collisions.
1273 		 */
1274 		if (txstat & (EMAC_TXS_UR | EMAC_TXS_ED))
1275 			ifp->if_oerrors++;
1276 
1277 #ifdef EMAC_EVENT_COUNTERS
1278 		if (txstat & EMAC_TXS_UR)
1279 			EMAC_EVCNT_INCR(&sc->sc_ev_tu);
1280 #endif /* EMAC_EVENT_COUNTERS */
1281 
1282 		if (txstat &
1283 		    (EMAC_TXS_EC | EMAC_TXS_MC | EMAC_TXS_SC | EMAC_TXS_LC)) {
1284 			if (txstat & EMAC_TXS_EC)
1285 				ifp->if_collisions += 16;
1286 			else if (txstat & EMAC_TXS_MC)
1287 				ifp->if_collisions += 2;	/* XXX? */
1288 			else if (txstat & EMAC_TXS_SC)
1289 				ifp->if_collisions++;
1290 			if (txstat & EMAC_TXS_LC)
1291 				ifp->if_collisions++;
1292 		} else
1293 			ifp->if_opackets++;
1294 
1295 		if (ifp->if_flags & IFF_DEBUG) {
1296 			if (txstat & EMAC_TXS_ED)
1297 				aprint_error_ifnet(ifp, "excessive deferral\n");
1298 			if (txstat & EMAC_TXS_EC)
1299 				aprint_error_ifnet(ifp,
1300 				    "excessive collisions\n");
1301 		}
1302 
1303 		sc->sc_txfree += txs->txs_ndesc;
1304 		bus_dmamap_sync(sc->sc_dmat, txs->txs_dmamap,
1305 		    0, txs->txs_dmamap->dm_mapsize, BUS_DMASYNC_POSTWRITE);
1306 		bus_dmamap_unload(sc->sc_dmat, txs->txs_dmamap);
1307 		m_freem(txs->txs_mbuf);
1308 		txs->txs_mbuf = NULL;
1309 	}
1310 
1311 	/* Update the dirty transmit buffer pointer. */
1312 	sc->sc_txsdirty = i;
1313 
1314 	/*
1315 	 * If there are no more pending transmissions, cancel the watchdog
1316 	 * timer.
1317 	 */
1318 	if (sc->sc_txsfree == EMAC_TXQUEUELEN)
1319 		ifp->if_timer = 0;
1320 
1321 	return handled;
1322 }
1323 
1324 
1325 /*
1326  * Reset functions
1327  */
1328 
1329 static void
1330 emac_soft_reset(struct emac_softc *sc)
1331 {
1332 	uint32_t sdr;
1333 	int t = 0;
1334 
1335 	/*
1336 	 * The PHY must provide a TX Clk in order perform a soft reset the
1337 	 * EMAC.  If none is present, select the internal clock,
1338 	 * SDR0_MFR[E0CS,E1CS].  After the soft reset, select the external
1339 	 * clock.
1340 	 */
1341 
1342 	sdr = mfsdr(DCR_SDR0_MFR);
1343 	sdr |= SDR0_MFR_ECS(sc->sc_instance);
1344 	mtsdr(DCR_SDR0_MFR, sdr);
1345 
1346 	EMAC_WRITE(sc, EMAC_MR0, MR0_SRST);
1347 
1348 	sdr = mfsdr(DCR_SDR0_MFR);
1349 	sdr &= ~SDR0_MFR_ECS(sc->sc_instance);
1350 	mtsdr(DCR_SDR0_MFR, sdr);
1351 
1352 	delay(5);
1353 
1354 	/* wait finish */
1355 	while (EMAC_READ(sc, EMAC_MR0) & MR0_SRST) {
1356 		if (++t == 1000000 /* 1sec XXXXX */) {
1357 			aprint_error_dev(sc->sc_dev, "Soft Reset failed\n");
1358 			return;
1359 		}
1360 		delay(1);
1361 	}
1362 }
1363 
1364 static void
1365 emac_smart_reset(struct emac_softc *sc)
1366 {
1367 	uint32_t mr0;
1368 	int t = 0;
1369 
1370 	mr0 = EMAC_READ(sc, EMAC_MR0);
1371 	if (mr0 & (MR0_TXE | MR0_RXE)) {
1372 		mr0 &= ~(MR0_TXE | MR0_RXE);
1373 		EMAC_WRITE(sc, EMAC_MR0, mr0);
1374 
1375 		/* wait idel state */
1376 		while ((EMAC_READ(sc, EMAC_MR0) & (MR0_TXI | MR0_RXI)) !=
1377 		    (MR0_TXI | MR0_RXI)) {
1378 			if (++t == 1000000 /* 1sec XXXXX */) {
1379 				aprint_error_dev(sc->sc_dev,
1380 				    "Smart Reset failed\n");
1381 				return;
1382 			}
1383 			delay(1);
1384 		}
1385 	}
1386 }
1387 
1388 
1389 /*
1390  * MII related functions
1391  */
1392 
1393 static int
1394 emac_mii_readreg(device_t self, int phy, int reg)
1395 {
1396 	struct emac_softc *sc = device_private(self);
1397 	uint32_t sta_reg;
1398 
1399 	if (sc->sc_rmii_enable)
1400 		sc->sc_rmii_enable(device_parent(self), sc->sc_instance);
1401 
1402 	/* wait for PHY data transfer to complete */
1403 	if (emac_mii_wait(sc))
1404 		goto fail;
1405 
1406 	sta_reg =
1407 	    sc->sc_stacr_read		|
1408 	    (reg << STACR_PRA_SHIFT)	|
1409 	    (phy << STACR_PCDA_SHIFT)	|
1410 	    sc->sc_stacr_bits;
1411 	EMAC_WRITE(sc, EMAC_STACR, sta_reg);
1412 
1413 	if (emac_mii_wait(sc))
1414 		goto fail;
1415 	sta_reg = EMAC_READ(sc, EMAC_STACR);
1416 
1417 	if (sc->sc_rmii_disable)
1418 		sc->sc_rmii_disable(device_parent(self), sc->sc_instance);
1419 
1420 	if (sta_reg & STACR_PHYE)
1421 		return 0;
1422 	return sta_reg >> STACR_PHYD_SHIFT;
1423 
1424 fail:
1425 	if (sc->sc_rmii_disable)
1426 		sc->sc_rmii_disable(device_parent(self), sc->sc_instance);
1427 	return 0;
1428 }
1429 
1430 static void
1431 emac_mii_writereg(device_t self, int phy, int reg, int val)
1432 {
1433 	struct emac_softc *sc = device_private(self);
1434 	uint32_t sta_reg;
1435 
1436 	if (sc->sc_rmii_enable)
1437 		sc->sc_rmii_enable(device_parent(self), sc->sc_instance);
1438 
1439 	/* wait for PHY data transfer to complete */
1440 	if (emac_mii_wait(sc))
1441 		goto out;
1442 
1443 	sta_reg =
1444 	    (val << STACR_PHYD_SHIFT)	|
1445 	    sc->sc_stacr_write		|
1446 	    (reg << STACR_PRA_SHIFT)	|
1447 	    (phy << STACR_PCDA_SHIFT)	|
1448 	    sc->sc_stacr_bits;
1449 	EMAC_WRITE(sc, EMAC_STACR, sta_reg);
1450 
1451 	if (emac_mii_wait(sc))
1452 		goto out;
1453 	if (EMAC_READ(sc, EMAC_STACR) & STACR_PHYE)
1454 		aprint_error_dev(sc->sc_dev, "MII PHY Error\n");
1455 
1456 out:
1457 	if (sc->sc_rmii_disable)
1458 		sc->sc_rmii_disable(device_parent(self), sc->sc_instance);
1459 }
1460 
1461 static void
1462 emac_mii_statchg(device_t self)
1463 {
1464 	struct emac_softc *sc = device_private(self);
1465 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1466 	struct mii_data *mii = &sc->sc_mii;
1467 
1468 	/*
1469 	 * MR1 can only be written immediately after a reset...
1470 	 */
1471 	emac_smart_reset(sc);
1472 
1473 	sc->sc_mr1 &= ~(MR1_FDE | MR1_ILE | MR1_EIFC | MR1_MF_MASK | MR1_IST);
1474 	if (mii->mii_media_active & IFM_FDX)
1475 		sc->sc_mr1 |= (MR1_FDE | MR1_EIFC | MR1_IST);
1476 	if (mii->mii_media_active & IFM_FLOW)
1477 		sc->sc_mr1 |= MR1_EIFC;
1478 	if (mii->mii_media_active & IFM_LOOP)
1479 		sc->sc_mr1 |= MR1_ILE;
1480 	switch (IFM_SUBTYPE(mii->mii_media_active)) {
1481 	case IFM_1000_T:
1482 		sc->sc_mr1 |= (MR1_MF_1000MBS | MR1_IST);
1483 		break;
1484 
1485 	case IFM_100_TX:
1486 		sc->sc_mr1 |= (MR1_MF_100MBS | MR1_IST);
1487 		break;
1488 
1489 	case IFM_10_T:
1490 		sc->sc_mr1 |= MR1_MF_10MBS;
1491 		break;
1492 
1493 	case IFM_NONE:
1494 		break;
1495 
1496 	default:
1497 		aprint_error_dev(self, "unknown sub-type %d\n",
1498 		    IFM_SUBTYPE(mii->mii_media_active));
1499 		break;
1500 	}
1501 	if (sc->sc_rmii_speed)
1502 		sc->sc_rmii_speed(device_parent(self), sc->sc_instance,
1503 		    IFM_SUBTYPE(mii->mii_media_active));
1504 
1505 	EMAC_WRITE(sc, EMAC_MR1, sc->sc_mr1);
1506 
1507 	/* Enable TX and RX if already RUNNING */
1508 	if (ifp->if_flags & IFF_RUNNING)
1509 		EMAC_WRITE(sc, EMAC_MR0, MR0_TXE | MR0_RXE);
1510 }
1511 
1512 static uint32_t
1513 emac_mii_wait(struct emac_softc *sc)
1514 {
1515 	int i;
1516 	uint32_t oc;
1517 
1518 	/* wait for PHY data transfer to complete */
1519 	i = 0;
1520 	oc = EMAC_READ(sc, EMAC_STACR) & STACR_OC;
1521 	while ((oc == STACR_OC) != sc->sc_stacr_completed) {
1522 		delay(7);
1523 		if (i++ > 5) {
1524 			aprint_error_dev(sc->sc_dev, "MII timed out\n");
1525 			return -1;
1526 		}
1527 		oc = EMAC_READ(sc, EMAC_STACR) & STACR_OC;
1528 	}
1529 	return 0;
1530 }
1531 
1532 static void
1533 emac_mii_tick(void *arg)
1534 {
1535 	struct emac_softc *sc = arg;
1536 	int s;
1537 
1538 	if (!device_is_active(sc->sc_dev))
1539 		return;
1540 
1541 	s = splnet();
1542 	mii_tick(&sc->sc_mii);
1543 	splx(s);
1544 
1545 	callout_reset(&sc->sc_callout, hz, emac_mii_tick, sc);
1546 }
1547 
1548 int
1549 emac_txeob_intr(void *arg)
1550 {
1551 	struct emac_softc *sc = arg;
1552 	int handled = 0;
1553 
1554 	EMAC_EVCNT_INCR(&sc->sc_ev_txintr);
1555 	handled |= emac_txreap(sc);
1556 
1557 	/* try to get more packets going */
1558 	emac_start(&sc->sc_ethercom.ec_if);
1559 
1560 	return handled;
1561 }
1562 
1563 int
1564 emac_rxeob_intr(void *arg)
1565 {
1566 	struct emac_softc *sc = arg;
1567 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1568 	struct emac_rxsoft *rxs;
1569 	struct mbuf *m;
1570 	uint32_t rxstat;
1571 	int i, len;
1572 
1573 	EMAC_EVCNT_INCR(&sc->sc_ev_rxintr);
1574 
1575 	for (i = sc->sc_rxptr; ; i = EMAC_NEXTRX(i)) {
1576 		rxs = &sc->sc_rxsoft[i];
1577 
1578 		EMAC_CDRXSYNC(sc, i,
1579 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1580 
1581 		rxstat = sc->sc_rxdescs[i].md_stat_ctrl;
1582 
1583 		if (rxstat & MAL_RX_EMPTY)
1584 			/*
1585 			 * We have processed all of the receive buffers.
1586 			 */
1587 			break;
1588 
1589 		/*
1590 		 * If an error occurred, update stats, clear the status
1591 		 * word, and leave the packet buffer in place.  It will
1592 		 * simply be reused the next time the ring comes around.
1593 		 */
1594 		if (rxstat & (EMAC_RXS_OE | EMAC_RXS_BP | EMAC_RXS_SE |
1595 		    EMAC_RXS_AE | EMAC_RXS_BFCS | EMAC_RXS_PTL | EMAC_RXS_ORE |
1596 		    EMAC_RXS_IRE)) {
1597 #define	PRINTERR(bit, str)					\
1598 			if (rxstat & (bit))			\
1599 				aprint_error_ifnet(ifp,		\
1600 				    "receive error: %s\n", str)
1601 			ifp->if_ierrors++;
1602 			PRINTERR(EMAC_RXS_OE, "overrun error");
1603 			PRINTERR(EMAC_RXS_BP, "bad packet");
1604 			PRINTERR(EMAC_RXS_RP, "runt packet");
1605 			PRINTERR(EMAC_RXS_SE, "short event");
1606 			PRINTERR(EMAC_RXS_AE, "alignment error");
1607 			PRINTERR(EMAC_RXS_BFCS, "bad FCS");
1608 			PRINTERR(EMAC_RXS_PTL, "packet too long");
1609 			PRINTERR(EMAC_RXS_ORE, "out of range error");
1610 			PRINTERR(EMAC_RXS_IRE, "in range error");
1611 #undef PRINTERR
1612 			EMAC_INIT_RXDESC(sc, i);
1613 			continue;
1614 		}
1615 
1616 		bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1617 		    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);
1618 
1619 		/*
1620 		 * No errors; receive the packet.  Note, the 405GP emac
1621 		 * includes the CRC with every packet.
1622 		 */
1623 		len = sc->sc_rxdescs[i].md_data_len - ETHER_CRC_LEN;
1624 
1625 		/*
1626 		 * If the packet is small enough to fit in a
1627 		 * single header mbuf, allocate one and copy
1628 		 * the data into it.  This greatly reduces
1629 		 * memory consumption when we receive lots
1630 		 * of small packets.
1631 		 *
1632 		 * Otherwise, we add a new buffer to the receive
1633 		 * chain.  If this fails, we drop the packet and
1634 		 * recycle the old buffer.
1635 		 */
1636 		if (emac_copy_small != 0 && len <= MHLEN) {
1637 			MGETHDR(m, M_DONTWAIT, MT_DATA);
1638 			if (m == NULL)
1639 				goto dropit;
1640 			memcpy(mtod(m, void *),
1641 			    mtod(rxs->rxs_mbuf, void *), len);
1642 			EMAC_INIT_RXDESC(sc, i);
1643 			bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1644 			    rxs->rxs_dmamap->dm_mapsize,
1645 			    BUS_DMASYNC_PREREAD);
1646 		} else {
1647 			m = rxs->rxs_mbuf;
1648 			if (emac_add_rxbuf(sc, i) != 0) {
1649  dropit:
1650 				ifp->if_ierrors++;
1651 				EMAC_INIT_RXDESC(sc, i);
1652 				bus_dmamap_sync(sc->sc_dmat,
1653 				    rxs->rxs_dmamap, 0,
1654 				    rxs->rxs_dmamap->dm_mapsize,
1655 				    BUS_DMASYNC_PREREAD);
1656 				continue;
1657 			}
1658 		}
1659 
1660 		ifp->if_ipackets++;
1661 		m->m_pkthdr.rcvif = ifp;
1662 		m->m_pkthdr.len = m->m_len = len;
1663 
1664 		/*
1665 		 * Pass this up to any BPF listeners, but only
1666 		 * pass if up the stack if it's for us.
1667 		 */
1668 		bpf_mtap(ifp, m);
1669 
1670 		/* Pass it on. */
1671 		(*ifp->if_input)(ifp, m);
1672 	}
1673 
1674 	/* Update the receive pointer. */
1675 	sc->sc_rxptr = i;
1676 
1677 	return 1;
1678 }
1679 
1680 int
1681 emac_txde_intr(void *arg)
1682 {
1683 	struct emac_softc *sc = arg;
1684 
1685 	EMAC_EVCNT_INCR(&sc->sc_ev_txde);
1686 	aprint_error_dev(sc->sc_dev, "emac_txde_intr\n");
1687 	return 1;
1688 }
1689 
1690 int
1691 emac_rxde_intr(void *arg)
1692 {
1693 	struct emac_softc *sc = arg;
1694 	int i;
1695 
1696 	EMAC_EVCNT_INCR(&sc->sc_ev_rxde);
1697 	aprint_error_dev(sc->sc_dev, "emac_rxde_intr\n");
1698 	/*
1699 	 * XXX!
1700 	 * This is a bit drastic; we just drop all descriptors that aren't
1701 	 * "clean".  We should probably send any that are up the stack.
1702 	 */
1703 	for (i = 0; i < EMAC_NRXDESC; i++) {
1704 		EMAC_CDRXSYNC(sc, i,
1705 		    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
1706 
1707 		if (sc->sc_rxdescs[i].md_data_len != MCLBYTES)
1708 			EMAC_INIT_RXDESC(sc, i);
1709 	}
1710 
1711 	return 1;
1712 }
1713