xref: /csrg-svn/sys/vax/if/if_en.c (revision 25272)
1 /*
2  * Copyright (c) 1982 Regents of the University of California.
3  * All rights reserved.  The Berkeley software License Agreement
4  * specifies the terms and conditions for redistribution.
5  *
6  *	@(#)if_en.c	6.10 (Berkeley) 10/24/85
7  */
8 
9 #include "en.h"
10 #if NEN > 0
11 
12 /*
13  * Xerox prototype (3 Mb) Ethernet interface driver.
14  */
15 #include "../machine/pte.h"
16 
17 #include "param.h"
18 #include "systm.h"
19 #include "mbuf.h"
20 #include "buf.h"
21 #include "protosw.h"
22 #include "socket.h"
23 #include "vmmac.h"
24 #include "errno.h"
25 #include "ioctl.h"
26 
27 #include "../net/if.h"
28 #include "../net/netisr.h"
29 #include "../net/route.h"
30 
31 #ifdef	BBNNET
32 #define	INET
33 #endif
34 #ifdef	INET
35 #include "../netinet/in.h"
36 #include "../netinet/in_systm.h"
37 #include "../netinet/in_var.h"
38 #include "../netinet/ip.h"
39 #endif
40 
41 #ifdef PUP
42 #include "../netpup/pup.h"
43 #include "../netpup/ether.h"
44 #endif
45 
46 #include "../vax/cpu.h"
47 #include "../vax/mtpr.h"
48 #include "if_en.h"
49 #include "if_enreg.h"
50 #include "if_uba.h"
51 #include "../vaxuba/ubareg.h"
52 #include "../vaxuba/ubavar.h"
53 
54 #define	ENMTU	(1024+512)
55 #define	ENMRU	(1024+512+16)		/* 16 is enough to receive trailer */
56 
57 int	enprobe(), enattach(), enrint(), enxint(), encollide();
58 struct	uba_device *eninfo[NEN];
59 u_short enstd[] = { 0 };
60 struct	uba_driver endriver =
61 	{ enprobe, 0, enattach, 0, enstd, "en", eninfo };
62 #define	ENUNIT(x)	minor(x)
63 
64 int	eninit(),enoutput(),enreset(),enioctl();
65 
66 #ifdef notdef
67 /*
68  * If you need to byte swap IP's in the system, define
69  * this and do a SIOCSIFFLAGS at boot time.
70  */
71 #define	ENF_SWABIPS	0x1000
72 #endif
73 
74 /*
75  * Ethernet software status per interface.
76  *
77  * Each interface is referenced by a network interface structure,
78  * es_if, which the routing code uses to locate the interface.
79  * This structure contains the output queue for the interface, its address, ...
80  * We also have, for each interface, a UBA interface structure, which
81  * contains information about the UNIBUS resources held by the interface:
82  * map registers, buffered data paths, etc.  Information is cached in this
83  * structure for use by the if_uba.c routines in running the interface
84  * efficiently.
85  */
86 struct	en_softc {
87 	struct	ifnet es_if;		/* network-visible interface */
88 	struct	ifuba es_ifuba;		/* UNIBUS resources */
89 	short	es_host;		/* hardware host number */
90 	short	es_delay;		/* current output delay */
91 	short	es_mask;		/* mask for current output delay */
92 	short	es_lastx;		/* host last transmitted to */
93 	short	es_oactive;		/* is output active? */
94 	short	es_olen;		/* length of last output */
95 } en_softc[NEN];
96 
97 /*
98  * Do output DMA to determine interface presence and
99  * interrupt vector.  DMA is too short to disturb other hosts.
100  */
101 enprobe(reg)
102 	caddr_t reg;
103 {
104 	register int br, cvec;		/* r11, r10 value-result */
105 	register struct endevice *addr = (struct endevice *)reg;
106 
107 #ifdef lint
108 	br = 0; cvec = br; br = cvec;
109 	enrint(0); enxint(0); encollide(0);
110 #endif
111 	addr->en_istat = 0;
112 	addr->en_owc = -1;
113 	addr->en_oba = 0;
114 	addr->en_ostat = EN_IEN|EN_GO;
115 	DELAY(100000);
116 	addr->en_ostat = 0;
117 	return (1);
118 }
119 
120 /*
121  * Interface exists: make available by filling in network interface
122  * record.  System will initialize the interface when it is ready
123  * to accept packets.
124  */
125 enattach(ui)
126 	struct uba_device *ui;
127 {
128 	register struct en_softc *es = &en_softc[ui->ui_unit];
129 
130 	es->es_if.if_unit = ui->ui_unit;
131 	es->es_if.if_name = "en";
132 	es->es_if.if_mtu = ENMTU;
133 	es->es_if.if_flags = IFF_BROADCAST;
134 	es->es_if.if_init = eninit;
135 	es->es_if.if_output = enoutput;
136 	es->es_if.if_ioctl = enioctl;
137 	es->es_if.if_reset = enreset;
138 	es->es_ifuba.ifu_flags = UBA_NEEDBDP | UBA_NEED16 | UBA_CANTWAIT;
139 #if defined(VAX750)
140 	/* don't chew up 750 bdp's */
141 	if (cpu == VAX_750 && ui->ui_unit > 0)
142 		es->es_ifuba.ifu_flags &= ~UBA_NEEDBDP;
143 #endif
144 	if_attach(&es->es_if);
145 }
146 
147 /*
148  * Reset of interface after UNIBUS reset.
149  * If interface is on specified uba, reset its state.
150  */
151 enreset(unit, uban)
152 	int unit, uban;
153 {
154 	register struct uba_device *ui;
155 
156 	if (unit >= NEN || (ui = eninfo[unit]) == 0 || ui->ui_alive == 0 ||
157 	    ui->ui_ubanum != uban)
158 		return;
159 	printf(" en%d", unit);
160 	eninit(unit);
161 }
162 
163 /*
164  * Initialization of interface; clear recorded pending
165  * operations, and reinitialize UNIBUS usage.
166  */
167 eninit(unit)
168 	int unit;
169 {
170 	register struct en_softc *es = &en_softc[unit];
171 	register struct uba_device *ui = eninfo[unit];
172 	register struct endevice *addr;
173 	int s;
174 
175 	if (es->es_if.if_addrlist == (struct ifaddr *)0)
176 		return;
177 	if (if_ubainit(&es->es_ifuba, ui->ui_ubanum,
178 	    sizeof (struct en_header), (int)btoc(ENMRU)) == 0) {
179 		printf("en%d: can't initialize\n", unit);
180 		es->es_if.if_flags &= ~IFF_UP;
181 		return;
182 	}
183 	addr = (struct endevice *)ui->ui_addr;
184 	addr->en_istat = addr->en_ostat = 0;
185 
186 	/*
187 	 * Hang a receive and start any
188 	 * pending writes by faking a transmit complete.
189 	 */
190 	s = splimp();
191 	addr->en_iba = es->es_ifuba.ifu_r.ifrw_info;
192 	addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1;
193 	addr->en_istat = EN_IEN|EN_GO;
194 	es->es_oactive = 1;
195 	es->es_if.if_flags |= IFF_RUNNING;
196 	enxint(unit);
197 	splx(s);
198 }
199 
200 int	enalldelay = 0;
201 int	enlastdel = 50;
202 int	enlastmask = (~0) << 5;
203 
204 /*
205  * Start or restart output on interface.
206  * If interface is already active, then this is a retransmit
207  * after a collision, and just restuff registers and delay.
208  * If interface is not already active, get another datagram
209  * to send off of the interface queue, and map it to the interface
210  * before starting the output.
211  */
212 enstart(dev)
213 	dev_t dev;
214 {
215         int unit = ENUNIT(dev);
216 	struct uba_device *ui = eninfo[unit];
217 	register struct en_softc *es = &en_softc[unit];
218 	register struct endevice *addr;
219 	register struct en_header *en;
220 	struct mbuf *m;
221 	int dest;
222 
223 	if (es->es_oactive)
224 		goto restart;
225 
226 	/*
227 	 * Not already active: dequeue another request
228 	 * and map it to the UNIBUS.  If no more requests,
229 	 * just return.
230 	 */
231 	IF_DEQUEUE(&es->es_if.if_snd, m);
232 	if (m == 0) {
233 		es->es_oactive = 0;
234 		return;
235 	}
236 	en = mtod(m, struct en_header *);
237 	dest = en->en_dhost;
238 	en->en_shost = es->es_host;
239 	es->es_olen = if_wubaput(&es->es_ifuba, m);
240 #ifdef ENF_SWABIPS
241 	/*
242 	 * The Xerox interface does word at a time DMA, so
243 	 * someone must do byte swapping of user data if high
244 	 * and low ender machines are to communicate.  It doesn't
245 	 * belong here, but certain people depend on it, so...
246 	 *
247 	 * Should swab everybody, but this is a kludge anyway.
248 	 */
249 	if (es->es_if.if_flags & ENF_SWABIPS) {
250 		en = (struct en_header *)es->es_ifuba.ifu_w.ifrw_addr;
251 		if (en->en_type == ENTYPE_IP)
252 			enswab((caddr_t)(en + 1), (caddr_t)(en + 1),
253 			    es->es_olen - sizeof (struct en_header) + 1);
254 	}
255 #endif
256 
257 	/*
258 	 * Ethernet cannot take back-to-back packets (no
259 	 * buffering in interface.  To help avoid overrunning
260 	 * receivers, enforce a small delay (about 1ms) in interface:
261 	 *	* between all packets when enalldelay
262 	 *	* whenever last packet was broadcast
263 	 *	* whenever this packet is to same host as last packet
264 	 */
265 	if (enalldelay || es->es_lastx == 0 || es->es_lastx == dest) {
266 		es->es_delay = enlastdel;
267 		es->es_mask = enlastmask;
268 	}
269 	es->es_lastx = dest;
270 
271 restart:
272 	/*
273 	 * Have request mapped to UNIBUS for transmission.
274 	 * Purge any stale data from this BDP, and start the otput.
275 	 */
276 	if (es->es_ifuba.ifu_flags & UBA_NEEDBDP)
277 		UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_w.ifrw_bdp);
278 	addr = (struct endevice *)ui->ui_addr;
279 	addr->en_oba = (int)es->es_ifuba.ifu_w.ifrw_info;
280 	addr->en_odelay = es->es_delay;
281 	addr->en_owc = -((es->es_olen + 1) >> 1);
282 	addr->en_ostat = EN_IEN|EN_GO;
283 	es->es_oactive = 1;
284 }
285 
286 /*
287  * Ethernet interface transmitter interrupt.
288  * Start another output if more data to send.
289  */
290 enxint(unit)
291 	int unit;
292 {
293 	register struct uba_device *ui = eninfo[unit];
294 	register struct en_softc *es = &en_softc[unit];
295 	register struct endevice *addr = (struct endevice *)ui->ui_addr;
296 
297 	if (es->es_oactive == 0)
298 		return;
299 	if (es->es_mask && (addr->en_ostat&EN_OERROR)) {
300 		es->es_if.if_oerrors++;
301 		endocoll(unit);
302 		return;
303 	}
304 	es->es_if.if_opackets++;
305 	es->es_oactive = 0;
306 	es->es_delay = 0;
307 	es->es_mask = ~0;
308 	if (es->es_ifuba.ifu_xtofree) {
309 		m_freem(es->es_ifuba.ifu_xtofree);
310 		es->es_ifuba.ifu_xtofree = 0;
311 	}
312 	if (es->es_if.if_snd.ifq_head == 0) {
313 		es->es_lastx = 256;		/* putatively illegal */
314 		return;
315 	}
316 	enstart(unit);
317 }
318 
319 /*
320  * Collision on ethernet interface.  Do exponential
321  * backoff, and retransmit.  If have backed off all
322  * the way print warning diagnostic, and drop packet.
323  */
324 encollide(unit)
325 	int unit;
326 {
327 	struct en_softc *es = &en_softc[unit];
328 
329 	es->es_if.if_collisions++;
330 	if (es->es_oactive == 0)
331 		return;
332 	endocoll(unit);
333 }
334 
335 endocoll(unit)
336 	int unit;
337 {
338 	register struct en_softc *es = &en_softc[unit];
339 
340 	/*
341 	 * Es_mask is a 16 bit number with n low zero bits, with
342 	 * n the number of backoffs.  When es_mask is 0 we have
343 	 * backed off 16 times, and give up.
344 	 */
345 	if (es->es_mask == 0) {
346 		printf("en%d: send error\n", unit);
347 		enxint(unit);
348 		return;
349 	}
350 	/*
351 	 * Another backoff.  Restart with delay based on n low bits
352 	 * of the interval timer.
353 	 */
354 	es->es_mask <<= 1;
355 	es->es_delay = mfpr(ICR) &~ es->es_mask;
356 	enstart(unit);
357 }
358 
359 #ifdef notdef
360 struct	sockproto enproto = { AF_ETHERLINK };
361 struct	sockaddr_en endst = { AF_ETHERLINK };
362 struct	sockaddr_en ensrc = { AF_ETHERLINK };
363 #endif
364 /*
365  * Ethernet interface receiver interrupt.
366  * If input error just drop packet.
367  * Otherwise purge input buffered data path and examine
368  * packet to determine type.  If can't determine length
369  * from type, then have to drop packet.  Othewise decapsulate
370  * packet based on type and pass to type specific higher-level
371  * input routine.
372  */
373 enrint(unit)
374 	int unit;
375 {
376 	register struct en_softc *es = &en_softc[unit];
377 	struct endevice *addr = (struct endevice *)eninfo[unit]->ui_addr;
378 	register struct en_header *en;
379     	struct mbuf *m;
380 	int len; short resid;
381 	register struct ifqueue *inq;
382 	int off, s;
383 
384 	es->es_if.if_ipackets++;
385 
386 	/*
387 	 * Purge BDP; drop if input error indicated.
388 	 */
389 	if (es->es_ifuba.ifu_flags & UBA_NEEDBDP)
390 		UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_r.ifrw_bdp);
391 	if (addr->en_istat&EN_IERROR) {
392 		es->es_if.if_ierrors++;
393 		goto setup;
394 	}
395 
396 	/*
397 	 * Calculate input data length.
398 	 * Get pointer to ethernet header (in input buffer).
399 	 * Deal with trailer protocol: if type is PUP trailer
400 	 * get true type from first 16-bit word past data.
401 	 * Remember that type was trailer by setting off.
402 	 */
403 	resid = addr->en_iwc;
404 	if (resid)
405 		resid |= 0176000;
406 	len = (((sizeof (struct en_header) + ENMRU) >> 1) + resid) << 1;
407 	len -= sizeof (struct en_header);
408 	if (len > ENMRU)
409 		goto setup;			/* sanity */
410 	en = (struct en_header *)(es->es_ifuba.ifu_r.ifrw_addr);
411 	en->en_type = ntohs(en->en_type);
412 #define	endataaddr(en, off, type)	((type)(((caddr_t)((en)+1)+(off))))
413 	if (en->en_type >= ENTYPE_TRAIL &&
414 	    en->en_type < ENTYPE_TRAIL+ENTYPE_NTRAILER) {
415 		off = (en->en_type - ENTYPE_TRAIL) * 512;
416 		if (off > ENMTU)
417 			goto setup;		/* sanity */
418 		en->en_type = ntohs(*endataaddr(en, off, u_short *));
419 		resid = ntohs(*(endataaddr(en, off+2, u_short *)));
420 		if (off + resid > len)
421 			goto setup;		/* sanity */
422 		len = off + resid;
423 	} else
424 		off = 0;
425 	if (len == 0)
426 		goto setup;
427 #ifdef ENF_SWABIPS
428 	if (es->es_if.if_flags & ENF_SWABIPS && en->en_type == ENTYPE_IP)
429 		enswab((caddr_t)(en + 1), (caddr_t)(en + 1), len);
430 #endif
431 	/*
432 	 * Pull packet off interface.  Off is nonzero if packet
433 	 * has trailing header; if_rubaget will then force this header
434 	 * information to be at the front, but we still have to drop
435 	 * the type and length which are at the front of any trailer data.
436 	 */
437 	m = if_rubaget(&es->es_ifuba, len, off, &es->es_if);
438 	if (m == 0)
439 		goto setup;
440 	if (off) {
441 		struct ifnet *ifp;
442 
443 		ifp = *(mtod(m, struct ifnet **));
444 		m->m_off += 2 * sizeof (u_short);
445 		m->m_len -= 2 * sizeof (u_short);
446 		*(mtod(m, struct ifnet **)) = ifp;
447 	}
448 	switch (en->en_type) {
449 
450 #ifdef INET
451 	case ENTYPE_IP:
452 		schednetisr(NETISR_IP);
453 		inq = &ipintrq;
454 		break;
455 #endif
456 #ifdef PUP
457 	case ENTYPE_PUP:
458 		rpup_input(m);
459 		goto setup;
460 #endif
461 	default:
462 #ifdef notdef
463 		enproto.sp_protocol = en->en_type;
464 		endst.sen_host = en->en_dhost;
465 		endst.sen_net = ensrc.sen_net = es->es_if.if_net;
466 		ensrc.sen_host = en->en_shost;
467 		raw_input(m, &enproto,
468 		    (struct sockaddr *)&ensrc, (struct sockaddr *)&endst);
469 #else
470 		m_freem(m);
471 #endif
472 		goto setup;
473 	}
474 
475 	s = splimp();
476 	if (IF_QFULL(inq)) {
477 		IF_DROP(inq);
478 		m_freem(m);
479 	} else
480 		IF_ENQUEUE(inq, m);
481 	splx(s);
482 
483 setup:
484 	/*
485 	 * Reset for next packet.
486 	 */
487 	addr->en_iba = es->es_ifuba.ifu_r.ifrw_info;
488 	addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1;
489 	addr->en_istat = EN_IEN|EN_GO;
490 }
491 
492 /*
493  * Ethernet output routine.
494  * Encapsulate a packet of type family for the local net.
495  * Use trailer local net encapsulation if enough data in first
496  * packet leaves a multiple of 512 bytes of data in remainder.
497  */
498 enoutput(ifp, m0, dst)
499 	struct ifnet *ifp;
500 	struct mbuf *m0;
501 	struct sockaddr *dst;
502 {
503 	int type, dest, s, error;
504 	register struct mbuf *m = m0;
505 	register struct en_header *en;
506 	register int off;
507 
508 	switch (dst->sa_family) {
509 
510 #ifdef INET
511 	case AF_INET:
512 		{
513 		struct in_addr in;
514 
515 		in = ((struct sockaddr_in *)dst)->sin_addr;
516 		if (in_broadcast(in))
517 			dest = EN_BROADCAST;
518 		else
519 			dest = in_lnaof(in);
520 		}
521 		if (dest >= 0x100) {
522 			error = EPERM;		/* ??? */
523 			goto bad;
524 		}
525 		off = ntohs((u_short)mtod(m, struct ip *)->ip_len) - m->m_len;
526 		/* need per host negotiation */
527 		if ((ifp->if_flags & IFF_NOTRAILERS) == 0)
528 		if (off > 0 && (off & 0x1ff) == 0 &&
529 		    m->m_off >= MMINOFF + 2 * sizeof (u_short)) {
530 			type = ENTYPE_TRAIL + (off>>9);
531 			m->m_off -= 2 * sizeof (u_short);
532 			m->m_len += 2 * sizeof (u_short);
533 			*mtod(m, u_short *) = htons((u_short)ENTYPE_IP);
534 			*(mtod(m, u_short *) + 1) = ntohs((u_short)m->m_len);
535 			goto gottrailertype;
536 		}
537 		type = ENTYPE_IP;
538 		off = 0;
539 		goto gottype;
540 #endif
541 #ifdef PUP
542 	case AF_PUP:
543 		dest = ((struct sockaddr_pup *)dst)->spup_host;
544 		type = ENTYPE_PUP;
545 		off = 0;
546 		goto gottype;
547 #endif
548 
549 #ifdef notdef
550 	case AF_ETHERLINK:
551 		goto gotheader;
552 #endif
553 
554 	default:
555 		printf("en%d: can't handle af%d\n", ifp->if_unit,
556 			dst->sa_family);
557 		error = EAFNOSUPPORT;
558 		goto bad;
559 	}
560 
561 gottrailertype:
562 	/*
563 	 * Packet to be sent as trailer: move first packet
564 	 * (control information) to end of chain.
565 	 */
566 	while (m->m_next)
567 		m = m->m_next;
568 	m->m_next = m0;
569 	m = m0->m_next;
570 	m0->m_next = 0;
571 	m0 = m;
572 
573 gottype:
574 	/*
575 	 * Add local net header.  If no space in first mbuf,
576 	 * allocate another.
577 	 */
578 	if (m->m_off > MMAXOFF ||
579 	    MMINOFF + sizeof (struct en_header) > m->m_off) {
580 		MGET(m, M_DONTWAIT, MT_HEADER);
581 		if (m == 0) {
582 			error = ENOBUFS;
583 			goto bad;
584 		}
585 		m->m_next = m0;
586 		m->m_off = MMINOFF;
587 		m->m_len = sizeof (struct en_header);
588 	} else {
589 		m->m_off -= sizeof (struct en_header);
590 		m->m_len += sizeof (struct en_header);
591 	}
592 	en = mtod(m, struct en_header *);
593 	/* add en_shost later */
594 	en->en_dhost = dest;
595 	en->en_type = htons((u_short)type);
596 
597 #ifdef notdef
598 gotheader:
599 #endif
600 	/*
601 	 * Queue message on interface, and start output if interface
602 	 * not yet active.
603 	 */
604 	s = splimp();
605 	if (IF_QFULL(&ifp->if_snd)) {
606 		IF_DROP(&ifp->if_snd);
607 		error = ENOBUFS;
608 		goto qfull;
609 	}
610 	IF_ENQUEUE(&ifp->if_snd, m);
611 	if (en_softc[ifp->if_unit].es_oactive == 0)
612 		enstart(ifp->if_unit);
613 	splx(s);
614 	return (0);
615 qfull:
616 	m0 = m;
617 	splx(s);
618 bad:
619 	m_freem(m0);
620 	return (error);
621 }
622 
623 /*
624  * Process an ioctl request.
625  */
626 enioctl(ifp, cmd, data)
627 	register struct ifnet *ifp;
628 	int cmd;
629 	caddr_t data;
630 {
631 	register struct en_softc *es = ((struct en_softc *)ifp);
632 	struct ifaddr *ifa = (struct ifaddr *) data;
633 	int s = splimp(), error = 0;
634 	struct endevice *enaddr;
635 
636 	switch (cmd) {
637 
638 	case SIOCSIFADDR:
639 		enaddr = (struct endevice *)eninfo[ifp->if_unit]->ui_addr;
640 		es->es_host = (~enaddr->en_addr) & 0xff;
641 		/*
642 		 * Attempt to check agreement of protocol address
643 		 * and board address.
644 		 */
645 		switch (ifa->ifa_addr.sa_family) {
646 		case AF_INET:
647 			if (in_lnaof(IA_SIN(ifa)->sin_addr) != es->es_host)
648 				return (EADDRNOTAVAIL);
649 			break;
650 		}
651 		ifp->if_flags |= IFF_UP;
652 		if ((ifp->if_flags & IFF_RUNNING) == 0)
653 			eninit(ifp->if_unit);
654 		break;
655 
656 	default:
657 		error = EINVAL;
658 		break;
659 	}
660 	splx(s);
661 	return (error);
662 }
663 
664 #ifdef ENF_SWABIPS
665 /*
666  * Swab bytes
667  * Jeffrey Mogul, Stanford
668  */
669 enswab(from, to, n)
670 	register unsigned char *from, *to;
671 	register int n;
672 {
673 	register unsigned long temp;
674 
675 	if ((n <= 0) || (n > 0xFFFF)) {
676 		printf("enswab: bad len %d\n", n);
677 		return;
678 	}
679 
680 	n >>= 1; n++;
681 #define	STEP	{temp = *from++;*to++ = *from++;*to++ = temp;}
682 	/* round to multiple of 8 */
683 	while ((--n) & 07)
684 		STEP;
685 	n >>= 3;
686 	while (--n >= 0) {
687 		STEP; STEP; STEP; STEP;
688 		STEP; STEP; STEP; STEP;
689 	}
690 }
691 #endif
692 #endif
693