xref: /csrg-svn/sys/vax/if/if_en.c (revision 12833)
1 /*	if_en.c	4.78	83/05/30	*/
2 
3 #include "en.h"
4 
5 /*
6  * Xerox prototype (3 Mb) Ethernet interface driver.
7  */
8 #include "../machine/pte.h"
9 
10 #include "../h/param.h"
11 #include "../h/systm.h"
12 #include "../h/mbuf.h"
13 #include "../h/buf.h"
14 #include "../h/protosw.h"
15 #include "../h/socket.h"
16 #include "../h/vmmac.h"
17 #include <errno.h>
18 
19 #include "../net/if.h"
20 #include "../net/netisr.h"
21 #include "../net/route.h"
22 #include "../netinet/in.h"
23 #include "../netinet/in_systm.h"
24 #include "../netinet/ip.h"
25 #include "../netinet/ip_var.h"
26 #include "../netpup/pup.h"
27 
28 #include "../vax/cpu.h"
29 #include "../vax/mtpr.h"
30 #include "../vaxif/if_en.h"
31 #include "../vaxif/if_enreg.h"
32 #include "../vaxif/if_uba.h"
33 #include "../vaxuba/ubareg.h"
34 #include "../vaxuba/ubavar.h"
35 
36 #define	ENMTU	(1024+512)
37 #define	ENMRU	(1024+512+16)		/* 16 is enough to receive trailer */
38 
39 int	enprobe(), enattach(), enrint(), enxint(), encollide();
40 struct	uba_device *eninfo[NEN];
41 u_short enstd[] = { 0 };
42 struct	uba_driver endriver =
43 	{ enprobe, 0, enattach, 0, enstd, "en", eninfo };
44 #define	ENUNIT(x)	minor(x)
45 
46 int	eninit(),enoutput(),enreset();
47 
48 /*
49  * Ethernet software status per interface.
50  *
51  * Each interface is referenced by a network interface structure,
52  * es_if, which the routing code uses to locate the interface.
53  * This structure contains the output queue for the interface, its address, ...
54  * We also have, for each interface, a UBA interface structure, which
55  * contains information about the UNIBUS resources held by the interface:
56  * map registers, buffered data paths, etc.  Information is cached in this
57  * structure for use by the if_uba.c routines in running the interface
58  * efficiently.
59  */
60 struct	en_softc {
61 	struct	ifnet es_if;		/* network-visible interface */
62 	struct	ifuba es_ifuba;		/* UNIBUS resources */
63 	short	es_delay;		/* current output delay */
64 	short	es_mask;		/* mask for current output delay */
65 	short	es_lastx;		/* host last transmitted to */
66 	short	es_oactive;		/* is output active? */
67 	short	es_olen;		/* length of last output */
68 } en_softc[NEN];
69 
70 /*
71  * Do output DMA to determine interface presence and
72  * interrupt vector.  DMA is too short to disturb other hosts.
73  */
74 enprobe(reg)
75 	caddr_t reg;
76 {
77 	register int br, cvec;		/* r11, r10 value-result */
78 	register struct endevice *addr = (struct endevice *)reg;
79 
80 #ifdef lint
81 	br = 0; cvec = br; br = cvec;
82 	enrint(0); enxint(0); encollide(0);
83 #endif
84 	addr->en_istat = 0;
85 	addr->en_owc = -1;
86 	addr->en_oba = 0;
87 	addr->en_ostat = EN_IEN|EN_GO;
88 	DELAY(100000);
89 	addr->en_ostat = 0;
90 #ifdef ECHACK
91 	br = 0x16;
92 #endif
93 	return (1);
94 }
95 
96 /*
97  * Interface exists: make available by filling in network interface
98  * record.  System will initialize the interface when it is ready
99  * to accept packets.
100  */
101 enattach(ui)
102 	struct uba_device *ui;
103 {
104 	register struct en_softc *es = &en_softc[ui->ui_unit];
105 
106 	es->es_if.if_unit = ui->ui_unit;
107 	es->es_if.if_name = "en";
108 	es->es_if.if_mtu = ENMTU;
109 	if (ui->ui_flags)
110 		ensetaddr(es, ui->ui_flags);
111 	es->es_if.if_init = eninit;
112 	es->es_if.if_output = enoutput;
113 	es->es_if.if_reset = enreset;
114 	es->es_ifuba.ifu_flags = UBA_NEEDBDP | UBA_NEED16 | UBA_CANTWAIT;
115 #if defined(VAX750)
116 	/* don't chew up 750 bdp's */
117 	if (cpu == VAX_750 && ui->ui_unit > 0)
118 		es->es_ifuba.ifu_flags &= ~UBA_NEEDBDP;
119 #endif
120 	if_attach(&es->es_if);
121 }
122 
123 /*
124  * Set interface's Internet address
125  * given the network number.  The station
126  * number, taken from the on-board register,
127  * is used as the local part.
128  */
129 ensetaddr(es, net)
130 	register struct en_softc *es;
131 	int net;
132 {
133 	struct endevice *enaddr;
134 	register struct sockaddr_in *sin;
135 
136 	es->es_if.if_net = net;
137 	enaddr = (struct endevice *)eninfo[es->es_if.if_unit]->ui_addr;
138 	es->es_if.if_host[0] = (~enaddr->en_addr) & 0xff;
139 	sin = (struct sockaddr_in *)&es->es_if.if_addr;
140 	sin->sin_family = AF_INET;
141 	sin->sin_addr = if_makeaddr(net, es->es_if.if_host[0]);
142 	sin = (struct sockaddr_in *)&es->es_if.if_broadaddr;
143 	sin->sin_family = AF_INET;
144 	sin->sin_addr = if_makeaddr(net, INADDR_ANY);
145 	es->es_if.if_flags |= IFF_BROADCAST;
146 }
147 
148 /*
149  * Reset of interface after UNIBUS reset.
150  * If interface is on specified uba, reset its state.
151  */
152 enreset(unit, uban)
153 	int unit, uban;
154 {
155 	register struct uba_device *ui;
156 
157 	if (unit >= NEN || (ui = eninfo[unit]) == 0 || ui->ui_alive == 0 ||
158 	    ui->ui_ubanum != uban)
159 		return;
160 	printf(" en%d", unit);
161 	eninit(unit);
162 }
163 
164 /*
165  * Initialization of interface; clear recorded pending
166  * operations, and reinitialize UNIBUS usage.
167  */
168 eninit(unit)
169 	int unit;
170 {
171 	register struct en_softc *es = &en_softc[unit];
172 	register struct uba_device *ui = eninfo[unit];
173 	register struct endevice *addr;
174 	struct sockaddr_in *sin = (struct sockaddr_in *)&es->es_if.if_addr;
175 	int net, s;
176 
177 	net = in_netof(sin->sin_addr);
178 	if (net == 0)
179 		return;
180 	ensetaddr(es, net);
181 #ifdef notdef
182 	if (es->es_if.if_flags & IFF_UP)
183 		return;
184 #endif
185 	if (if_ubainit(&es->es_ifuba, ui->ui_ubanum,
186 	    sizeof (struct en_header), (int)btoc(ENMRU)) == 0) {
187 		printf("en%d: can't initialize\n", unit);
188 		es->es_if.if_flags &= ~IFF_UP;
189 		return;
190 	}
191 	addr = (struct endevice *)ui->ui_addr;
192 	addr->en_istat = addr->en_ostat = 0;
193 
194 	/*
195 	 * Hang a receive and start any
196 	 * pending writes by faking a transmit complete.
197 	 */
198 	s = splimp();
199 	addr->en_iba = es->es_ifuba.ifu_r.ifrw_info;
200 	addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1;
201 	addr->en_istat = EN_IEN|EN_GO;
202 	es->es_oactive = 1;
203 	es->es_if.if_flags |= IFF_UP;
204 	enxint(unit);
205 	splx(s);
206 	if_rtinit(&es->es_if, RTF_UP);
207 }
208 
209 int	enalldelay = 0;
210 int	enlastdel = 50;
211 int	enlastmask = (~0) << 5;
212 
213 /*
214  * Start or restart output on interface.
215  * If interface is already active, then this is a retransmit
216  * after a collision, and just restuff registers and delay.
217  * If interface is not already active, get another datagram
218  * to send off of the interface queue, and map it to the interface
219  * before starting the output.
220  */
221 enstart(dev)
222 	dev_t dev;
223 {
224         int unit = ENUNIT(dev);
225 	struct uba_device *ui = eninfo[unit];
226 	register struct en_softc *es = &en_softc[unit];
227 	register struct endevice *addr;
228 	struct mbuf *m;
229 	int dest;
230 
231 	if (es->es_oactive)
232 		goto restart;
233 
234 	/*
235 	 * Not already active: dequeue another request
236 	 * and map it to the UNIBUS.  If no more requests,
237 	 * just return.
238 	 */
239 	IF_DEQUEUE(&es->es_if.if_snd, m);
240 	if (m == 0) {
241 		es->es_oactive = 0;
242 		return;
243 	}
244 	dest = mtod(m, struct en_header *)->en_dhost;
245 	es->es_olen = if_wubaput(&es->es_ifuba, m);
246 
247 	/*
248 	 * Ethernet cannot take back-to-back packets (no
249 	 * buffering in interface.  To help avoid overrunning
250 	 * receivers, enforce a small delay (about 1ms) in interface:
251 	 *	* between all packets when enalldelay
252 	 *	* whenever last packet was broadcast
253 	 *	* whenever this packet is to same host as last packet
254 	 */
255 	if (enalldelay || es->es_lastx == 0 || es->es_lastx == dest) {
256 		es->es_delay = enlastdel;
257 		es->es_mask = enlastmask;
258 	}
259 	es->es_lastx = dest;
260 
261 restart:
262 	/*
263 	 * Have request mapped to UNIBUS for transmission.
264 	 * Purge any stale data from this BDP, and start the otput.
265 	 */
266 	if (es->es_ifuba.ifu_flags & UBA_NEEDBDP)
267 		UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_w.ifrw_bdp);
268 	addr = (struct endevice *)ui->ui_addr;
269 	addr->en_oba = (int)es->es_ifuba.ifu_w.ifrw_info;
270 	addr->en_odelay = es->es_delay;
271 	addr->en_owc = -((es->es_olen + 1) >> 1);
272 	addr->en_ostat = EN_IEN|EN_GO;
273 	es->es_oactive = 1;
274 }
275 
276 /*
277  * Ethernet interface transmitter interrupt.
278  * Start another output if more data to send.
279  */
280 enxint(unit)
281 	int unit;
282 {
283 	register struct uba_device *ui = eninfo[unit];
284 	register struct en_softc *es = &en_softc[unit];
285 	register struct endevice *addr = (struct endevice *)ui->ui_addr;
286 
287 	if (es->es_oactive == 0)
288 		return;
289 	if (es->es_mask && (addr->en_ostat&EN_OERROR)) {
290 		es->es_if.if_oerrors++;
291 		endocoll(unit);
292 		return;
293 	}
294 	es->es_if.if_opackets++;
295 	es->es_oactive = 0;
296 	es->es_delay = 0;
297 	es->es_mask = ~0;
298 	if (es->es_ifuba.ifu_xtofree) {
299 		m_freem(es->es_ifuba.ifu_xtofree);
300 		es->es_ifuba.ifu_xtofree = 0;
301 	}
302 	if (es->es_if.if_snd.ifq_head == 0) {
303 		es->es_lastx = 256;		/* putatively illegal */
304 		return;
305 	}
306 	enstart(unit);
307 }
308 
309 /*
310  * Collision on ethernet interface.  Do exponential
311  * backoff, and retransmit.  If have backed off all
312  * the way print warning diagnostic, and drop packet.
313  */
314 encollide(unit)
315 	int unit;
316 {
317 	struct en_softc *es = &en_softc[unit];
318 
319 	es->es_if.if_collisions++;
320 	if (es->es_oactive == 0)
321 		return;
322 	endocoll(unit);
323 }
324 
325 endocoll(unit)
326 	int unit;
327 {
328 	register struct en_softc *es = &en_softc[unit];
329 
330 	/*
331 	 * Es_mask is a 16 bit number with n low zero bits, with
332 	 * n the number of backoffs.  When es_mask is 0 we have
333 	 * backed off 16 times, and give up.
334 	 */
335 	if (es->es_mask == 0) {
336 		printf("en%d: send error\n", unit);
337 		enxint(unit);
338 		return;
339 	}
340 	/*
341 	 * Another backoff.  Restart with delay based on n low bits
342 	 * of the interval timer.
343 	 */
344 	es->es_mask <<= 1;
345 	es->es_delay = mfpr(ICR) &~ es->es_mask;
346 	enstart(unit);
347 }
348 
349 struct	sockaddr_pup pupsrc = { AF_PUP };
350 struct	sockaddr_pup pupdst = { AF_PUP };
351 struct	sockproto pupproto = { PF_PUP };
352 /*
353  * Ethernet interface receiver interrupt.
354  * If input error just drop packet.
355  * Otherwise purge input buffered data path and examine
356  * packet to determine type.  If can't determine length
357  * from type, then have to drop packet.  Othewise decapsulate
358  * packet based on type and pass to type specific higher-level
359  * input routine.
360  */
361 enrint(unit)
362 	int unit;
363 {
364 	register struct en_softc *es = &en_softc[unit];
365 	struct endevice *addr = (struct endevice *)eninfo[unit]->ui_addr;
366 	register struct en_header *en;
367     	struct mbuf *m;
368 	int len; short resid;
369 	register struct ifqueue *inq;
370 	int off;
371 
372 	es->es_if.if_ipackets++;
373 
374 	/*
375 	 * Purge BDP; drop if input error indicated.
376 	 */
377 	if (es->es_ifuba.ifu_flags & UBA_NEEDBDP)
378 		UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_r.ifrw_bdp);
379 	if (addr->en_istat&EN_IERROR) {
380 		es->es_if.if_ierrors++;
381 		goto setup;
382 	}
383 
384 	/*
385 	 * Calculate input data length.
386 	 * Get pointer to ethernet header (in input buffer).
387 	 * Deal with trailer protocol: if type is PUP trailer
388 	 * get true type from first 16-bit word past data.
389 	 * Remember that type was trailer by setting off.
390 	 */
391 	resid = addr->en_iwc;
392 	if (resid)
393 		resid |= 0176000;
394 	len = (((sizeof (struct en_header) + ENMRU) >> 1) + resid) << 1;
395 	len -= sizeof (struct en_header);
396 	if (len > ENMRU)
397 		goto setup;			/* sanity */
398 	en = (struct en_header *)(es->es_ifuba.ifu_r.ifrw_addr);
399 	en->en_type = ntohs(en->en_type);
400 #define	endataaddr(en, off, type)	((type)(((caddr_t)((en)+1)+(off))))
401 	if (en->en_type >= ENTYPE_TRAIL &&
402 	    en->en_type < ENTYPE_TRAIL+ENTYPE_NTRAILER) {
403 		off = (en->en_type - ENTYPE_TRAIL) * 512;
404 		if (off > ENMTU)
405 			goto setup;		/* sanity */
406 		en->en_type = ntohs(*endataaddr(en, off, u_short *));
407 		resid = ntohs(*(endataaddr(en, off+2, u_short *)));
408 		if (off + resid > len)
409 			goto setup;		/* sanity */
410 		len = off + resid;
411 	} else
412 		off = 0;
413 	if (len == 0)
414 		goto setup;
415 	/*
416 	 * Pull packet off interface.  Off is nonzero if packet
417 	 * has trailing header; if_rubaget will then force this header
418 	 * information to be at the front, but we still have to drop
419 	 * the type and length which are at the front of any trailer data.
420 	 */
421 	m = if_rubaget(&es->es_ifuba, len, off);
422 	if (m == 0)
423 		goto setup;
424 	if (off) {
425 		m->m_off += 2 * sizeof (u_short);
426 		m->m_len -= 2 * sizeof (u_short);
427 	}
428 	switch (en->en_type) {
429 
430 #ifdef INET
431 	case ENTYPE_IP:
432 		schednetisr(NETISR_IP);
433 		inq = &ipintrq;
434 		break;
435 #endif
436 #ifdef PUP
437 	case ENTYPE_PUP: {
438 		struct pup_header *pup = mtod(m, struct pup_header *);
439 
440 		pupproto.sp_protocol = pup->pup_type;
441 		bcopy((caddr_t)pup->pup_dnet, (caddr_t)pupdst.spup_net,
442 		    sizeof (struct pupport));
443 		bcopy((caddr_t)pup->pup_snet, (caddr_t)pupsrc.spup_net,
444 		    sizeof (struct pupport));
445 		raw_input(m, &pupproto, (struct sockaddr *)&pupsrc,
446 		  (struct sockaddr *)&pupdst);
447 		goto setup;
448 	}
449 #endif
450 	default:
451 		m_freem(m);
452 		goto setup;
453 	}
454 
455 	if (IF_QFULL(inq)) {
456 		IF_DROP(inq);
457 		m_freem(m);
458 	} else
459 		IF_ENQUEUE(inq, m);
460 
461 setup:
462 	/*
463 	 * Reset for next packet.
464 	 */
465 	addr->en_iba = es->es_ifuba.ifu_r.ifrw_info;
466 	addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1;
467 	addr->en_istat = EN_IEN|EN_GO;
468 }
469 
470 /*
471  * Ethernet output routine.
472  * Encapsulate a packet of type family for the local net.
473  * Use trailer local net encapsulation if enough data in first
474  * packet leaves a multiple of 512 bytes of data in remainder.
475  */
476 enoutput(ifp, m0, dst)
477 	struct ifnet *ifp;
478 	struct mbuf *m0;
479 	struct sockaddr *dst;
480 {
481 	int type, dest, s, error;
482 	register struct mbuf *m = m0;
483 	register struct en_header *en;
484 	register int off;
485 
486 	switch (dst->sa_family) {
487 
488 #ifdef INET
489 	case AF_INET:
490 		dest = ((struct sockaddr_in *)dst)->sin_addr.s_addr;
491 		if (in_lnaof(*((struct in_addr *)&dest)) >= 0x100) {
492 			error = EPERM;		/* ??? */
493 			goto bad;
494 		}
495 		dest = (dest >> 24) & 0xff;
496 		off = ntohs((u_short)mtod(m, struct ip *)->ip_len) - m->m_len;
497 		if (off > 0 && (off & 0x1ff) == 0 &&
498 		    m->m_off >= MMINOFF + 2 * sizeof (u_short)) {
499 			type = ENTYPE_TRAIL + (off>>9);
500 			m->m_off -= 2 * sizeof (u_short);
501 			m->m_len += 2 * sizeof (u_short);
502 			*mtod(m, u_short *) = htons((u_short)ENTYPE_IP);
503 			*(mtod(m, u_short *) + 1) = ntohs((u_short)m->m_len);
504 			goto gottrailertype;
505 		}
506 		type = ENTYPE_IP;
507 		off = 0;
508 		goto gottype;
509 #endif
510 #ifdef PUP
511 	case AF_PUP:
512 		dest = ((struct sockaddr_pup *)dst)->spup_host;
513 		type = ENTYPE_PUP;
514 		off = 0;
515 		goto gottype;
516 #endif
517 
518 	default:
519 		printf("en%d: can't handle af%d\n", ifp->if_unit,
520 			dst->sa_family);
521 		error = EAFNOSUPPORT;
522 		goto bad;
523 	}
524 
525 gottrailertype:
526 	/*
527 	 * Packet to be sent as trailer: move first packet
528 	 * (control information) to end of chain.
529 	 */
530 	while (m->m_next)
531 		m = m->m_next;
532 	m->m_next = m0;
533 	m = m0->m_next;
534 	m0->m_next = 0;
535 	m0 = m;
536 
537 gottype:
538 	/*
539 	 * Add local net header.  If no space in first mbuf,
540 	 * allocate another.
541 	 */
542 	if (m->m_off > MMAXOFF ||
543 	    MMINOFF + sizeof (struct en_header) > m->m_off) {
544 		m = m_get(M_DONTWAIT, MT_HEADER);
545 		if (m == 0) {
546 			error = ENOBUFS;
547 			goto bad;
548 		}
549 		m->m_next = m0;
550 		m->m_off = MMINOFF;
551 		m->m_len = sizeof (struct en_header);
552 	} else {
553 		m->m_off -= sizeof (struct en_header);
554 		m->m_len += sizeof (struct en_header);
555 	}
556 	en = mtod(m, struct en_header *);
557 	en->en_shost = ifp->if_host[0];
558 	en->en_dhost = dest;
559 	en->en_type = htons((u_short)type);
560 
561 	/*
562 	 * Queue message on interface, and start output if interface
563 	 * not yet active.
564 	 */
565 	s = splimp();
566 	if (IF_QFULL(&ifp->if_snd)) {
567 		IF_DROP(&ifp->if_snd);
568 		error = ENOBUFS;
569 		goto qfull;
570 	}
571 	IF_ENQUEUE(&ifp->if_snd, m);
572 	if (en_softc[ifp->if_unit].es_oactive == 0)
573 		enstart(ifp->if_unit);
574 	splx(s);
575 	return (0);
576 qfull:
577 	m0 = m;
578 	splx(s);
579 bad:
580 	m_freem(m0);
581 	return (error);
582 }
583