xref: /netbsd-src/sys/arch/next68k/dev/if_xe.c (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*	$NetBSD: if_xe.c,v 1.22 2012/10/27 17:18:05 chs Exp $	*/
2 /*
3  * Copyright (c) 1998 Darrin B. Jewell
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __KERNEL_RCSID(0, "$NetBSD: if_xe.c,v 1.22 2012/10/27 17:18:05 chs Exp $");
29 
30 #include "opt_inet.h"
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/mbuf.h>
35 #include <sys/syslog.h>
36 #include <sys/socket.h>
37 #include <sys/device.h>
38 
39 #include <net/if.h>
40 #include <net/if_ether.h>
41 #include <net/if_media.h>
42 
43 #ifdef INET
44 #include <netinet/in.h>
45 #include <netinet/if_inarp.h>
46 #endif
47 
48 #include <machine/autoconf.h>
49 #include <machine/cpu.h>
50 #include <machine/intr.h>
51 #include <machine/bus.h>
52 
53 #include <next68k/next68k/isr.h>
54 
55 #include <next68k/dev/mb8795reg.h>
56 #include <next68k/dev/mb8795var.h>
57 
58 #include <next68k/dev/bmapreg.h>
59 #include <next68k/dev/intiovar.h>
60 #include <next68k/dev/nextdmareg.h>
61 #include <next68k/dev/nextdmavar.h>
62 
63 #include <next68k/dev/if_xevar.h>
64 #include <next68k/dev/if_xereg.h>
65 
66 #ifdef DEBUG
67 #define XE_DEBUG
68 #endif
69 
70 #ifdef XE_DEBUG
71 int xe_debug = 0;
72 #define DPRINTF(x) if (xe_debug) printf x;
73 extern char *ndtracep;
74 extern char ndtrace[];
75 extern int ndtraceshow;
76 #define NDTRACEIF(x) if (10 && ndtracep < (ndtrace + 8192)) do {x;} while (0)
77 #else
78 #define DPRINTF(x)
79 #define NDTRACEIF(x)
80 #endif
81 #define PRINTF(x) printf x;
82 
83 extern int turbo;
84 
85 int	xe_match(device_t, cfdata_t, void *);
86 void	xe_attach(device_t, device_t, void *);
87 int	xe_tint(void *);
88 int	xe_rint(void *);
89 
90 struct mbuf * xe_dma_rxmap_load(struct mb8795_softc *, bus_dmamap_t);
91 
92 bus_dmamap_t xe_dma_rx_continue(void *);
93 void xe_dma_rx_completed(bus_dmamap_t, void *);
94 bus_dmamap_t xe_dma_tx_continue(void *);
95 void xe_dma_tx_completed(bus_dmamap_t, void *);
96 void xe_dma_rx_shutdown(void *);
97 void xe_dma_tx_shutdown(void *);
98 
99 static void	findchannel_defer(device_t);
100 
101 CFATTACH_DECL_NEW(xe, sizeof(struct xe_softc),
102     xe_match, xe_attach, NULL, NULL);
103 
104 static int xe_dma_medias[] = {
105 	IFM_ETHER|IFM_AUTO,
106 	IFM_ETHER|IFM_10_T,
107 	IFM_ETHER|IFM_10_2,
108 };
109 static int nxe_dma_medias = (sizeof(xe_dma_medias)/sizeof(xe_dma_medias[0]));
110 
111 static int attached = 0;
112 
113 /*
114  * Functions and the switch for the MI code.
115  */
116 u_char		xe_read_reg(struct mb8795_softc *, int);
117 void		xe_write_reg(struct mb8795_softc *, int, u_char);
118 void		xe_dma_reset(struct mb8795_softc *);
119 void		xe_dma_rx_setup(struct mb8795_softc *);
120 void		xe_dma_rx_go(struct mb8795_softc *);
121 struct mbuf *	xe_dma_rx_mbuf(struct mb8795_softc *);
122 void		xe_dma_tx_setup(struct mb8795_softc *);
123 void		xe_dma_tx_go(struct mb8795_softc *);
124 int		xe_dma_tx_mbuf(struct mb8795_softc *, struct mbuf *);
125 int		xe_dma_tx_isactive(struct mb8795_softc *);
126 
127 struct mb8795_glue xe_glue = {
128 	xe_read_reg,
129 	xe_write_reg,
130 	xe_dma_reset,
131 	xe_dma_rx_setup,
132 	xe_dma_rx_go,
133 	xe_dma_rx_mbuf,
134 	xe_dma_tx_setup,
135 	xe_dma_tx_go,
136 	xe_dma_tx_mbuf,
137 	xe_dma_tx_isactive,
138 };
139 
140 int
141 xe_match(device_t parent, cfdata_t match, void *aux)
142 {
143 	struct intio_attach_args *ia = (struct intio_attach_args *)aux;
144 
145 	if (attached)
146 		return (0);
147 
148 	ia->ia_addr = (void *)NEXT_P_ENET;
149 
150 	return (1);
151 }
152 
153 static void
154 findchannel_defer(device_t self)
155 {
156 	struct xe_softc *xsc = device_private(self);
157 	struct mb8795_softc *sc = &xsc->sc_mb8795;
158 	int i, error;
159 
160 	if (!xsc->sc_txdma) {
161 		xsc->sc_txdma = nextdma_findchannel ("enetx");
162 		if (xsc->sc_txdma == NULL)
163 			panic("%s: can't find enetx DMA channel",
164 			       device_xname(sc->sc_dev));
165 	}
166 	if (!xsc->sc_rxdma) {
167 		xsc->sc_rxdma = nextdma_findchannel ("enetr");
168 		if (xsc->sc_rxdma == NULL)
169 			panic ("%s: can't find enetr DMA channel",
170 			       device_xname(sc->sc_dev));
171 	}
172 	aprint_normal_dev(sc->sc_dev, "using DMA channels %s %s\n",
173 		device_xname(xsc->sc_txdma->sc_dev),
174 		device_xname(xsc->sc_rxdma->sc_dev));
175 
176 	nextdma_setconf (xsc->sc_rxdma, continue_cb, xe_dma_rx_continue);
177 	nextdma_setconf (xsc->sc_rxdma, completed_cb, xe_dma_rx_completed);
178 	nextdma_setconf (xsc->sc_rxdma, shutdown_cb, xe_dma_rx_shutdown);
179 	nextdma_setconf (xsc->sc_rxdma, cb_arg, sc);
180 
181 	nextdma_setconf (xsc->sc_txdma, continue_cb, xe_dma_tx_continue);
182 	nextdma_setconf (xsc->sc_txdma, completed_cb, xe_dma_tx_completed);
183 	nextdma_setconf (xsc->sc_txdma, shutdown_cb, xe_dma_tx_shutdown);
184 	nextdma_setconf (xsc->sc_txdma, cb_arg, sc);
185 
186 	/* Initialize the DMA maps */
187 	error = bus_dmamap_create(xsc->sc_txdma->sc_dmat, MCLBYTES,
188 				  (MCLBYTES/MSIZE), MCLBYTES, 0, BUS_DMA_ALLOCNOW,
189 				  &xsc->sc_tx_dmamap);
190 	if (error) {
191 		aprint_error_dev(sc->sc_dev, "can't create tx DMA map, error = %d",
192 		      error);
193 	}
194 
195 	for(i = 0; i < MB8795_NRXBUFS; i++) {
196 		error = bus_dmamap_create(xsc->sc_rxdma->sc_dmat, MCLBYTES,
197 					  (MCLBYTES/MSIZE), MCLBYTES, 0, BUS_DMA_ALLOCNOW,
198 					  &xsc->sc_rx_dmamap[i]);
199 		if (error) {
200 			panic("%s: can't create rx DMA map, error = %d",
201 			      device_xname(sc->sc_dev), error);
202 		}
203 		xsc->sc_rx_mb_head[i] = NULL;
204 	}
205 	xsc->sc_rx_loaded_idx = 0;
206 	xsc->sc_rx_completed_idx = 0;
207 	xsc->sc_rx_handled_idx = 0;
208 
209 	/* @@@ more next hacks
210 	 * the  2000 covers at least a 1500 mtu + headers
211 	 * + DMA_BEGINALIGNMENT+ DMA_ENDALIGNMENT
212 	 */
213 	xsc->sc_txbuf = malloc(2000, M_DEVBUF, M_NOWAIT);
214 	if (!xsc->sc_txbuf)
215 		panic("%s: can't malloc tx DMA buffer", device_xname(sc->sc_dev));
216 
217 	xsc->sc_tx_mb_head = NULL;
218 	xsc->sc_tx_loaded = 0;
219 
220 	mb8795_config(sc, xe_dma_medias, nxe_dma_medias, xe_dma_medias[0]);
221 
222 	isrlink_autovec(xe_tint, sc, NEXT_I_IPL(NEXT_I_ENETX), 1, NULL);
223 	INTR_ENABLE(NEXT_I_ENETX);
224 	isrlink_autovec(xe_rint, sc, NEXT_I_IPL(NEXT_I_ENETR), 1, NULL);
225 	INTR_ENABLE(NEXT_I_ENETR);
226 }
227 
228 void
229 xe_attach(device_t parent, device_t self, void *aux)
230 {
231 	struct intio_attach_args *ia = (struct intio_attach_args *)aux;
232 	struct xe_softc *xsc = device_private(self);
233 	struct mb8795_softc *sc = &xsc->sc_mb8795;
234 
235 	sc->sc_dev = self;
236 	DPRINTF(("%s: xe_attach()\n", device_xname(self)));
237 
238 	{
239 		extern u_char rom_enetaddr[6];     /* kludge from machdep.c:next68k_bootargs() */
240 		int i;
241 		for(i=0;i<6;i++) {
242 			sc->sc_enaddr[i] = rom_enetaddr[i];
243 		}
244 	}
245 
246 	printf("\n%s: MAC address %02x:%02x:%02x:%02x:%02x:%02x\n",
247 	       device_xname(self),
248 	       sc->sc_enaddr[0],sc->sc_enaddr[1],sc->sc_enaddr[2],
249 	       sc->sc_enaddr[3],sc->sc_enaddr[4],sc->sc_enaddr[5]);
250 
251 	xsc->sc_bst = ia->ia_bst;
252 	if (bus_space_map(xsc->sc_bst, NEXT_P_ENET,
253 			  XE_DEVICE_SIZE, 0, &xsc->sc_bsh)) {
254 		panic("\n%s: can't map mb8795 registers",
255 		      device_xname(self));
256 	}
257 
258 	sc->sc_bmap_bst = ia->ia_bst;
259 	if (bus_space_map(sc->sc_bmap_bst, NEXT_P_BMAP,
260 			  BMAP_SIZE, 0, &sc->sc_bmap_bsh)) {
261 		panic("\n%s: can't map bmap registers",
262 		      device_xname(self));
263 	}
264 
265 	/*
266 	 * Set up glue for MI code.
267 	 */
268 	sc->sc_glue = &xe_glue;
269 
270 	xsc->sc_txdma = nextdma_findchannel("enetx");
271 	xsc->sc_rxdma = nextdma_findchannel("enetr");
272 	if (xsc->sc_rxdma && xsc->sc_txdma) {
273 		findchannel_defer(self);
274 	} else {
275 		config_defer(self, findchannel_defer);
276 	}
277 
278 	attached = 1;
279 }
280 
281 int
282 xe_tint(void *arg)
283 {
284 	if (!INTR_OCCURRED(NEXT_I_ENETX))
285 		return 0;
286 	mb8795_tint((struct mb8795_softc *)arg);
287 	return(1);
288 }
289 
290 int
291 xe_rint(void *arg)
292 {
293 	if (!INTR_OCCURRED(NEXT_I_ENETR))
294 		return(0);
295 	mb8795_rint((struct mb8795_softc *)arg);
296 	return(1);
297 }
298 
299 /*
300  * Glue functions.
301  */
302 
303 u_char
304 xe_read_reg(struct mb8795_softc *sc, int reg)
305 {
306 	struct xe_softc *xsc = (struct xe_softc *)sc;
307 
308 	return(bus_space_read_1(xsc->sc_bst, xsc->sc_bsh, reg));
309 }
310 
311 void
312 xe_write_reg(struct mb8795_softc *sc, int reg, u_char val)
313 {
314 	struct xe_softc *xsc = (struct xe_softc *)sc;
315 
316 	bus_space_write_1(xsc->sc_bst, xsc->sc_bsh, reg, val);
317 }
318 
319 void
320 xe_dma_reset(struct mb8795_softc *sc)
321 {
322 	struct xe_softc *xsc = (struct xe_softc *)sc;
323 	int i;
324 
325 	DPRINTF(("xe DMA reset\n"));
326 
327 	nextdma_reset(xsc->sc_rxdma);
328 	nextdma_reset(xsc->sc_txdma);
329 
330 	if (xsc->sc_tx_loaded) {
331 		bus_dmamap_sync(xsc->sc_txdma->sc_dmat, xsc->sc_tx_dmamap,
332 				0, xsc->sc_tx_dmamap->dm_mapsize,
333 				BUS_DMASYNC_POSTWRITE);
334 		bus_dmamap_unload(xsc->sc_txdma->sc_dmat, xsc->sc_tx_dmamap);
335 		xsc->sc_tx_loaded = 0;
336 	}
337 	if (xsc->sc_tx_mb_head) {
338 		m_freem(xsc->sc_tx_mb_head);
339 		xsc->sc_tx_mb_head = NULL;
340 	}
341 
342 	for(i = 0; i < MB8795_NRXBUFS; i++) {
343 		if (xsc->sc_rx_mb_head[i]) {
344 			bus_dmamap_unload(xsc->sc_rxdma->sc_dmat, xsc->sc_rx_dmamap[i]);
345 			m_freem(xsc->sc_rx_mb_head[i]);
346 			xsc->sc_rx_mb_head[i] = NULL;
347 		}
348 	}
349 }
350 
351 void
352 xe_dma_rx_setup(struct mb8795_softc *sc)
353 {
354 	struct xe_softc *xsc = (struct xe_softc *)sc;
355 	int i;
356 
357 	DPRINTF(("xe DMA rx setup\n"));
358 
359 	for(i = 0; i < MB8795_NRXBUFS; i++) {
360 		xsc->sc_rx_mb_head[i] =
361 			xe_dma_rxmap_load(sc, xsc->sc_rx_dmamap[i]);
362 	}
363 	xsc->sc_rx_loaded_idx = 0;
364 	xsc->sc_rx_completed_idx = 0;
365 	xsc->sc_rx_handled_idx = 0;
366 
367 	nextdma_init(xsc->sc_rxdma);
368 }
369 
370 void
371 xe_dma_rx_go(struct mb8795_softc *sc)
372 {
373 	struct xe_softc *xsc = (struct xe_softc *)sc;
374 
375 	DPRINTF(("xe DMA rx go\n"));
376 
377 	nextdma_start(xsc->sc_rxdma, DMACSR_SETREAD);
378 }
379 
380 struct mbuf *
381 xe_dma_rx_mbuf(struct mb8795_softc *sc)
382 {
383 	struct xe_softc *xsc = (struct xe_softc *)sc;
384 	bus_dmamap_t map;
385 	struct mbuf *m;
386 
387 	m = NULL;
388 	if (xsc->sc_rx_handled_idx != xsc->sc_rx_completed_idx) {
389 		xsc->sc_rx_handled_idx++;
390 		xsc->sc_rx_handled_idx %= MB8795_NRXBUFS;
391 
392 		map = xsc->sc_rx_dmamap[xsc->sc_rx_handled_idx];
393 		m = xsc->sc_rx_mb_head[xsc->sc_rx_handled_idx];
394 
395 		m->m_len = map->dm_xfer_len;
396 
397 		bus_dmamap_sync(xsc->sc_rxdma->sc_dmat, map,
398 				0, map->dm_mapsize, BUS_DMASYNC_POSTREAD);
399 
400 		bus_dmamap_unload(xsc->sc_rxdma->sc_dmat, map);
401 
402 		/* Install a fresh mbuf for next packet */
403 
404 		xsc->sc_rx_mb_head[xsc->sc_rx_handled_idx] =
405 			xe_dma_rxmap_load(sc,map);
406 
407 		/* Punt runt packets
408 		 * DMA restarts create 0 length packets for example
409 		 */
410 		if (m->m_len < ETHER_MIN_LEN) {
411 			m_freem(m);
412 			m = NULL;
413 		}
414 	}
415 	return (m);
416 }
417 
418 void
419 xe_dma_tx_setup(struct mb8795_softc *sc)
420 {
421 	struct xe_softc *xsc = (struct xe_softc *)sc;
422 
423 	DPRINTF(("xe DMA tx setup\n"));
424 
425 	nextdma_init(xsc->sc_txdma);
426 }
427 
428 void
429 xe_dma_tx_go(struct mb8795_softc *sc)
430 {
431 	struct xe_softc *xsc = (struct xe_softc *)sc;
432 
433 	DPRINTF(("xe DMA tx go\n"));
434 
435 	nextdma_start(xsc->sc_txdma, DMACSR_SETWRITE);
436 }
437 
438 int
439 xe_dma_tx_mbuf(struct mb8795_softc *sc, struct mbuf *m)
440 {
441 	struct xe_softc *xsc = (struct xe_softc *)sc;
442 	int error;
443 
444 	xsc->sc_tx_mb_head = m;
445 
446 /* The following is a next specific hack that should
447  * probably be moved out of MI code.
448  * This macro assumes it can move forward as needed
449  * in the buffer.  Perhaps it should zero the extra buffer.
450  */
451 #define REALIGN_DMABUF(s,l) \
452 	{ (s) = ((u_char *)(((unsigned)(s)+DMA_BEGINALIGNMENT-1) \
453 			&~(DMA_BEGINALIGNMENT-1))); \
454     (l) = ((u_char *)(((unsigned)((s)+(l))+DMA_ENDALIGNMENT-1) \
455 				&~(DMA_ENDALIGNMENT-1)))-(s);}
456 
457 #if 0
458 	error = bus_dmamap_load_mbuf(xsc->sc_txdma->sc_dmat,
459 				     xsc->sc_tx_dmamap, xsc->sc_tx_mb_head, BUS_DMA_NOWAIT);
460 #else
461 	{
462 		u_char *buf = xsc->sc_txbuf;
463 		int buflen = 0;
464 
465 		buflen = m->m_pkthdr.len;
466 
467 		{
468 			u_char *p = buf;
469 			for (m=xsc->sc_tx_mb_head; m; m = m->m_next) {
470 				if (m->m_len == 0) continue;
471 				memcpy(p, mtod(m, u_char *), m->m_len);
472 				p += m->m_len;
473 			}
474 			/* Fix runt packets */
475 			if (buflen < ETHER_MIN_LEN - ETHER_CRC_LEN) {
476 				memset(p, 0,
477 				    ETHER_MIN_LEN - ETHER_CRC_LEN - buflen);
478 				buflen = ETHER_MIN_LEN - ETHER_CRC_LEN;
479 			}
480 		}
481 
482 		error = bus_dmamap_load(xsc->sc_txdma->sc_dmat, xsc->sc_tx_dmamap,
483 					buf,buflen,NULL,BUS_DMA_NOWAIT);
484 	}
485 #endif
486 	if (error) {
487 		aprint_error_dev(sc->sc_dev, "can't load mbuf chain, error = %d\n",
488 		    error);
489 		m_freem(xsc->sc_tx_mb_head);
490 		xsc->sc_tx_mb_head = NULL;
491 		return (error);
492 	}
493 
494 #ifdef DIAGNOSTIC
495 	if (xsc->sc_tx_loaded != 0) {
496 		panic("%s: xsc->sc_tx_loaded is %d", device_xname(sc->sc_dev),
497 		      xsc->sc_tx_loaded);
498 	}
499 #endif
500 
501 	bus_dmamap_sync(xsc->sc_txdma->sc_dmat, xsc->sc_tx_dmamap, 0,
502 			xsc->sc_tx_dmamap->dm_mapsize, BUS_DMASYNC_PREWRITE);
503 
504 	return (0);
505 }
506 
507 int
508 xe_dma_tx_isactive(struct mb8795_softc *sc)
509 {
510 	struct xe_softc *xsc = (struct xe_softc *)sc;
511 
512 	return (xsc->sc_tx_loaded != 0);
513 }
514 
515 /****************************************************************/
516 
517 void
518 xe_dma_tx_completed(bus_dmamap_t map, void *arg)
519 {
520 #if defined (XE_DEBUG) || defined (DIAGNOSTIC)
521 	struct mb8795_softc *sc = arg;
522 #endif
523 #ifdef DIAGNOSTIC
524 	struct xe_softc *xsc = (struct xe_softc *)sc;
525 #endif
526 
527 	DPRINTF(("%s: xe_dma_tx_completed()\n", device_xname(sc->sc_dev)));
528 
529 #ifdef DIAGNOSTIC
530 	if (!xsc->sc_tx_loaded) {
531 		panic("%s: tx completed never loaded", device_xname(sc->sc_dev));
532 	}
533 	if (map != xsc->sc_tx_dmamap) {
534 		panic("%s: unexpected tx completed map", device_xname(sc->sc_dev));
535 	}
536 
537 #endif
538 }
539 
540 void
541 xe_dma_tx_shutdown(void *arg)
542 {
543 	struct mb8795_softc *sc = arg;
544 	struct xe_softc *xsc = (struct xe_softc *)sc;
545 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
546 
547 	DPRINTF(("%s: xe_dma_tx_shutdown()\n", device_xname(sc->sc_dev)));
548 
549 #ifdef DIAGNOSTIC
550 	if (!xsc->sc_tx_loaded) {
551 		panic("%s: tx shutdown never loaded", device_xname(sc->sc_dev));
552 	}
553 #endif
554 
555 	if (turbo)
556 		MB_WRITE_REG(sc, MB8795_TXMODE, MB8795_TXMODE_TURBO1);
557 	if (xsc->sc_tx_loaded) {
558 		bus_dmamap_sync(xsc->sc_txdma->sc_dmat, xsc->sc_tx_dmamap,
559 				0, xsc->sc_tx_dmamap->dm_mapsize,
560 				BUS_DMASYNC_POSTWRITE);
561 		bus_dmamap_unload(xsc->sc_txdma->sc_dmat, xsc->sc_tx_dmamap);
562 		m_freem(xsc->sc_tx_mb_head);
563 		xsc->sc_tx_mb_head = NULL;
564 
565 		xsc->sc_tx_loaded--;
566 	}
567 
568 #ifdef DIAGNOSTIC
569 	if (xsc->sc_tx_loaded != 0) {
570 		panic("%s: sc->sc_tx_loaded is %d", device_xname(sc->sc_dev),
571 		      xsc->sc_tx_loaded);
572 	}
573 #endif
574 
575 	ifp->if_timer = 0;
576 
577 #if 1
578 	if ((ifp->if_flags & IFF_RUNNING) && !IF_IS_EMPTY(&sc->sc_tx_snd)) {
579 		void mb8795_start_dma(struct mb8795_softc *); /* XXXX */
580 		mb8795_start_dma(sc);
581 	}
582 #endif
583 
584 #if 0
585 	/* Enable ready interrupt */
586 	MB_WRITE_REG(sc, MB8795_TXMASK,
587 		     MB_READ_REG(sc, MB8795_TXMASK)
588 		     | MB8795_TXMASK_TXRXIE/* READYIE */);
589 #endif
590 }
591 
592 
593 void
594 xe_dma_rx_completed(bus_dmamap_t map, void *arg)
595 {
596 	struct mb8795_softc *sc = arg;
597 	struct xe_softc *xsc = (struct xe_softc *)sc;
598 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
599 
600 	if (ifp->if_flags & IFF_RUNNING) {
601 		xsc->sc_rx_completed_idx++;
602 		xsc->sc_rx_completed_idx %= MB8795_NRXBUFS;
603 
604 		DPRINTF(("%s: xe_dma_rx_completed(), sc->sc_rx_completed_idx = %d\n",
605 			 device_xname(sc->sc_dev), xsc->sc_rx_completed_idx));
606 
607 #if (defined(DIAGNOSTIC))
608 		if (map != xsc->sc_rx_dmamap[xsc->sc_rx_completed_idx]) {
609 			panic("%s: Unexpected rx dmamap completed",
610 			      device_xname(sc->sc_dev));
611 		}
612 #endif
613 	}
614 #ifdef DIAGNOSTIC
615 	else
616 		DPRINTF(("%s: Unexpected rx dmamap completed while if not running\n",
617 			 device_xname(sc->sc_dev)));
618 #endif
619 }
620 
621 void
622 xe_dma_rx_shutdown(void *arg)
623 {
624 	struct mb8795_softc *sc = arg;
625 	struct xe_softc *xsc = (struct xe_softc *)sc;
626 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
627 
628 	if (ifp->if_flags & IFF_RUNNING) {
629 		DPRINTF(("%s: xe_dma_rx_shutdown(), restarting.\n",
630 			 device_xname(sc->sc_dev)));
631 
632 		nextdma_start(xsc->sc_rxdma, DMACSR_SETREAD);
633 		if (turbo)
634 			MB_WRITE_REG(sc, MB8795_RXMODE, MB8795_RXMODE_TEST | MB8795_RXMODE_MULTICAST);
635 	}
636 #ifdef DIAGNOSTIC
637 	else
638 		DPRINTF(("%s: Unexpected rx DMA shutdown while if not running\n",
639 			 device_xname(sc->sc_dev)));
640 #endif
641 }
642 
643 /*
644  * load a dmamap with a freshly allocated mbuf
645  */
646 struct mbuf *
647 xe_dma_rxmap_load(struct mb8795_softc *sc, bus_dmamap_t map)
648 {
649 	struct xe_softc *xsc = (struct xe_softc *)sc;
650 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
651 	struct mbuf *m;
652 	int error;
653 
654 	MGETHDR(m, M_DONTWAIT, MT_DATA);
655 	if (m) {
656 		MCLGET(m, M_DONTWAIT);
657 		if ((m->m_flags & M_EXT) == 0) {
658 			m_freem(m);
659 			m = NULL;
660 		} else {
661 			m->m_len = MCLBYTES;
662 		}
663 	}
664 	if (!m) {
665 		/* @@@ Handle this gracefully by reusing a scratch buffer
666 		 * or something.
667 		 */
668 		panic("Unable to get memory for incoming ethernet");
669 	}
670 
671 	/* Align buffer, @@@ next specific.
672 	 * perhaps should be using M_ALIGN here instead?
673 	 * First we give us a little room to align with.
674 	 */
675 	{
676 		u_char *buf = m->m_data;
677 		int buflen = m->m_len;
678 		buflen -= DMA_ENDALIGNMENT+DMA_BEGINALIGNMENT;
679 		REALIGN_DMABUF(buf, buflen);
680 		m->m_data = buf;
681 		m->m_len = buflen;
682 	}
683 
684 	m->m_pkthdr.rcvif = ifp;
685 	m->m_pkthdr.len = m->m_len;
686 
687 	error = bus_dmamap_load_mbuf(xsc->sc_rxdma->sc_dmat,
688 			map, m, BUS_DMA_NOWAIT);
689 
690 	bus_dmamap_sync(xsc->sc_rxdma->sc_dmat, map, 0,
691 			map->dm_mapsize, BUS_DMASYNC_PREREAD);
692 
693 	if (error) {
694 		DPRINTF(("DEBUG: m->m_data = %p, m->m_len = %d\n",
695 				m->m_data, m->m_len));
696 		DPRINTF(("DEBUG: MCLBYTES = %d, map->_dm_size = %ld\n",
697 				MCLBYTES, map->_dm_size));
698 
699 		panic("%s: can't load rx mbuf chain, error = %d",
700 				device_xname(sc->sc_dev), error);
701 		m_freem(m);
702 		m = NULL;
703 	}
704 
705 	return(m);
706 }
707 
708 bus_dmamap_t
709 xe_dma_rx_continue(void *arg)
710 {
711 	struct mb8795_softc *sc = arg;
712 	struct xe_softc *xsc = (struct xe_softc *)sc;
713 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
714 	bus_dmamap_t map = NULL;
715 
716 	if (ifp->if_flags & IFF_RUNNING) {
717 		if (((xsc->sc_rx_loaded_idx+1)%MB8795_NRXBUFS) == xsc->sc_rx_handled_idx) {
718 			/* make space for one packet by dropping one */
719 			struct mbuf *m;
720 			m = xe_dma_rx_mbuf (sc);
721 			if (m)
722 				m_freem(m);
723 #if (defined(DIAGNOSTIC))
724 			DPRINTF(("%s: out of receive DMA buffers\n", device_xname(sc->sc_dev)));
725 #endif
726 		}
727 		xsc->sc_rx_loaded_idx++;
728 		xsc->sc_rx_loaded_idx %= MB8795_NRXBUFS;
729 		map = xsc->sc_rx_dmamap[xsc->sc_rx_loaded_idx];
730 
731 		DPRINTF(("%s: xe_dma_rx_continue() xsc->sc_rx_loaded_idx = %d\nn",
732 			 device_xname(sc->sc_dev), xsc->sc_rx_loaded_idx));
733 	}
734 #ifdef DIAGNOSTIC
735 	else
736 		panic("%s: Unexpected rx DMA continue while if not running",
737 		      device_xname(sc->sc_dev));
738 #endif
739 
740 	return(map);
741 }
742 
743 bus_dmamap_t
744 xe_dma_tx_continue(void *arg)
745 {
746 	struct mb8795_softc *sc = arg;
747 	struct xe_softc *xsc = (struct xe_softc *)sc;
748 	bus_dmamap_t map;
749 
750 	DPRINTF(("%s: xe_dma_tx_continue()\n", device_xname(sc->sc_dev)));
751 
752 	if (xsc->sc_tx_loaded) {
753 		map = NULL;
754 	} else {
755 		map = xsc->sc_tx_dmamap;
756 		xsc->sc_tx_loaded++;
757 	}
758 
759 #ifdef DIAGNOSTIC
760 	if (xsc->sc_tx_loaded != 1) {
761 		panic("%s: sc->sc_tx_loaded is %d", device_xname(sc->sc_dev),
762 				xsc->sc_tx_loaded);
763 	}
764 #endif
765 
766 	return(map);
767 }
768