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-rw-r--r--drivers/char/rio/rioroute.c1238
1 files changed, 1238 insertions, 0 deletions
diff --git a/drivers/char/rio/rioroute.c b/drivers/char/rio/rioroute.c
new file mode 100644
index 000000000000..106b31f48a21
--- /dev/null
+++ b/drivers/char/rio/rioroute.c
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1/*
2** -----------------------------------------------------------------------------
3**
4** Perle Specialix driver for Linux
5** Ported from existing RIO Driver for SCO sources.
6 *
7 * (C) 1990 - 2000 Specialix International Ltd., Byfleet, Surrey, UK.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22**
23** Module : rioroute.c
24** SID : 1.3
25** Last Modified : 11/6/98 10:33:46
26** Retrieved : 11/6/98 10:33:50
27**
28** ident @(#)rioroute.c 1.3
29**
30** -----------------------------------------------------------------------------
31*/
32#ifdef SCCS_LABELS
33static char *_rioroute_c_sccs_ = "@(#)rioroute.c 1.3";
34#endif
35
36#include <linux/module.h>
37#include <linux/slab.h>
38#include <linux/errno.h>
39#include <asm/io.h>
40#include <asm/system.h>
41#include <asm/string.h>
42#include <asm/semaphore.h>
43#include <asm/uaccess.h>
44
45#include <linux/termios.h>
46#include <linux/serial.h>
47
48#include <linux/generic_serial.h>
49
50
51#include "linux_compat.h"
52#include "rio_linux.h"
53#include "typdef.h"
54#include "pkt.h"
55#include "daemon.h"
56#include "rio.h"
57#include "riospace.h"
58#include "top.h"
59#include "cmdpkt.h"
60#include "map.h"
61#include "riotypes.h"
62#include "rup.h"
63#include "port.h"
64#include "riodrvr.h"
65#include "rioinfo.h"
66#include "func.h"
67#include "errors.h"
68#include "pci.h"
69
70#include "parmmap.h"
71#include "unixrup.h"
72#include "board.h"
73#include "host.h"
74#include "error.h"
75#include "phb.h"
76#include "link.h"
77#include "cmdblk.h"
78#include "route.h"
79#include "control.h"
80#include "cirrus.h"
81#include "rioioctl.h"
82#include "param.h"
83#include "list.h"
84#include "sam.h"
85
86static int RIOCheckIsolated(struct rio_info *, struct Host *, uint);
87static int RIOIsolate(struct rio_info *, struct Host *, uint);
88static int RIOCheck(struct Host *, uint);
89static void RIOConCon(struct rio_info *, struct Host *, uint, uint, uint, uint, int);
90
91
92/*
93** Incoming on the ROUTE_RUP
94** I wrote this while I was tired. Forgive me.
95*/
96int RIORouteRup( struct rio_info *p, uint Rup, struct Host *HostP, PKT *PacketP )
97{
98 struct PktCmd *PktCmdP = (struct PktCmd *)PacketP->data;
99 struct PktCmd_M *PktReplyP;
100 struct CmdBlk *CmdBlkP;
101 struct Port *PortP;
102 struct Map *MapP;
103 struct Top *TopP;
104 int ThisLink, ThisLinkMin, ThisLinkMax;
105 int port;
106 int Mod, Mod1, Mod2;
107 ushort RtaType;
108 uint RtaUniq;
109 uint ThisUnit, ThisUnit2; /* 2 ids to accommodate 16 port RTA */
110 uint OldUnit, NewUnit, OldLink, NewLink;
111 char *MyType, *MyName;
112 int Lies;
113 unsigned long flags;
114
115#ifdef STACK
116 RIOStackCheck("RIORouteRup");
117#endif
118#ifdef CHECK
119 CheckPacketP(PacketP);
120 CheckHostP(HostP);
121 CheckRup(Rup);
122 CheckHost(Host);
123#endif
124 /*
125 ** Is this unit telling us it's current link topology?
126 */
127 if ( RBYTE(PktCmdP->Command) == ROUTE_TOPOLOGY )
128 {
129 MapP = HostP->Mapping;
130
131 /*
132 ** The packet can be sent either by the host or by an RTA.
133 ** If it comes from the host, then we need to fill in the
134 ** Topology array in the host structure. If it came in
135 ** from an RTA then we need to fill in the Mapping structure's
136 ** Topology array for the unit.
137 */
138 if ( Rup >= (ushort)MAX_RUP )
139 {
140 ThisUnit = HOST_ID;
141 TopP = HostP->Topology;
142 MyType = "Host";
143 MyName = HostP->Name;
144 ThisLinkMin = ThisLinkMax = Rup - MAX_RUP;
145 }
146 else
147 {
148 ThisUnit = Rup+1;
149 TopP = HostP->Mapping[Rup].Topology;
150 MyType = "RTA";
151 MyName = HostP->Mapping[Rup].Name;
152 ThisLinkMin = 0;
153 ThisLinkMax = LINKS_PER_UNIT - 1;
154 }
155
156 /*
157 ** Lies will not be tolerated.
158 ** If any pair of links claim to be connected to the same
159 ** place, then ignore this packet completely.
160 */
161 Lies = 0;
162 for ( ThisLink=ThisLinkMin + 1; ThisLink <= ThisLinkMax; ThisLink++)
163 {
164 /*
165 ** it won't lie about network interconnect, total disconnects
166 ** and no-IDs. (or at least, it doesn't *matter* if it does)
167 */
168 if ( RBYTE(PktCmdP->RouteTopology[ThisLink].Unit) > (ushort)MAX_RUP )
169 continue;
170
171 for ( NewLink=ThisLinkMin; NewLink < ThisLink; NewLink++ )
172 {
173 if ( (RBYTE(PktCmdP->RouteTopology[ThisLink].Unit) ==
174 RBYTE(PktCmdP->RouteTopology[NewLink].Unit)) &&
175 (RBYTE(PktCmdP->RouteTopology[ThisLink].Link) ==
176 RBYTE(PktCmdP->RouteTopology[NewLink].Link)) )
177 {
178 Lies++;
179 }
180 }
181 }
182
183 if ( Lies )
184 {
185 rio_dprintk (RIO_DEBUG_ROUTE, "LIES! DAMN LIES! %d LIES!\n",Lies);
186 rio_dprintk (RIO_DEBUG_ROUTE, "%d:%c %d:%c %d:%c %d:%c\n",
187 RBYTE(PktCmdP->RouteTopology[0].Unit),
188 'A'+RBYTE(PktCmdP->RouteTopology[0].Link),
189 RBYTE(PktCmdP->RouteTopology[1].Unit),
190 'A'+RBYTE(PktCmdP->RouteTopology[1].Link),
191 RBYTE(PktCmdP->RouteTopology[2].Unit),
192 'A'+RBYTE(PktCmdP->RouteTopology[2].Link),
193 RBYTE(PktCmdP->RouteTopology[3].Unit),
194 'A'+RBYTE(PktCmdP->RouteTopology[3].Link));
195 return TRUE;
196 }
197
198 /*
199 ** now, process each link.
200 */
201 for ( ThisLink=ThisLinkMin; ThisLink <= ThisLinkMax; ThisLink++)
202 {
203 /*
204 ** this is what it was connected to
205 */
206 OldUnit = TopP[ThisLink].Unit;
207 OldLink = TopP[ThisLink].Link;
208
209 /*
210 ** this is what it is now connected to
211 */
212 NewUnit = RBYTE(PktCmdP->RouteTopology[ThisLink].Unit);
213 NewLink = RBYTE(PktCmdP->RouteTopology[ThisLink].Link);
214
215 if ( OldUnit != NewUnit || OldLink != NewLink )
216 {
217 /*
218 ** something has changed!
219 */
220
221 if ( NewUnit > MAX_RUP &&
222 NewUnit != ROUTE_DISCONNECT &&
223 NewUnit != ROUTE_NO_ID &&
224 NewUnit != ROUTE_INTERCONNECT )
225 {
226 rio_dprintk (RIO_DEBUG_ROUTE, "I have a link from %s %s to unit %d:%d - I don't like it.\n",
227 MyType,
228 MyName,
229 NewUnit,
230 NewLink);
231 }
232 else
233 {
234 /*
235 ** put the new values in
236 */
237 TopP[ThisLink].Unit = NewUnit;
238 TopP[ThisLink].Link = NewLink;
239
240 RIOSetChange(p);
241
242 if ( OldUnit <= MAX_RUP )
243 {
244 /*
245 ** If something has become bust, then re-enable them messages
246 */
247 if (! p->RIONoMessage)
248 RIOConCon(p,HostP,ThisUnit,ThisLink,OldUnit,OldLink,DISCONNECT);
249 }
250
251 if ( ( NewUnit <= MAX_RUP ) && !p->RIONoMessage )
252 RIOConCon(p,HostP,ThisUnit,ThisLink,NewUnit,NewLink,CONNECT);
253
254 if ( NewUnit == ROUTE_NO_ID )
255 rio_dprintk (RIO_DEBUG_ROUTE, "%s %s (%c) is connected to an unconfigured unit.\n",
256 MyType,MyName,'A'+ThisLink);
257
258 if ( NewUnit == ROUTE_INTERCONNECT )
259 {
260 if (! p->RIONoMessage)
261 cprintf("%s '%s' (%c) is connected to another network.\n", MyType,MyName,'A'+ThisLink);
262 }
263
264 /*
265 ** perform an update for 'the other end', so that these messages
266 ** only appears once. Only disconnect the other end if it is pointing
267 ** at us!
268 */
269 if ( OldUnit == HOST_ID )
270 {
271 if ( HostP->Topology[OldLink].Unit == ThisUnit &&
272 HostP->Topology[OldLink].Link == ThisLink )
273 {
274 rio_dprintk (RIO_DEBUG_ROUTE, "SETTING HOST (%c) TO DISCONNECTED!\n", OldLink+'A');
275 HostP->Topology[OldLink].Unit = ROUTE_DISCONNECT;
276 HostP->Topology[OldLink].Link = NO_LINK;
277 }
278 else
279 {
280 rio_dprintk (RIO_DEBUG_ROUTE, "HOST(%c) WAS NOT CONNECTED TO %s (%c)!\n",
281 OldLink+'A',HostP->Mapping[ThisUnit-1].Name,ThisLink+'A');
282 }
283 }
284 else if ( OldUnit <= MAX_RUP )
285 {
286 if ( HostP->Mapping[OldUnit-1].Topology[OldLink].Unit == ThisUnit &&
287 HostP->Mapping[OldUnit-1].Topology[OldLink].Link == ThisLink )
288 {
289 rio_dprintk (RIO_DEBUG_ROUTE, "SETTING RTA %s (%c) TO DISCONNECTED!\n",
290 HostP->Mapping[OldUnit-1].Name,OldLink+'A');
291 HostP->Mapping[OldUnit-1].Topology[OldLink].Unit=ROUTE_DISCONNECT;
292 HostP->Mapping[OldUnit-1].Topology[OldLink].Link=NO_LINK;
293 }
294 else
295 {
296 rio_dprintk (RIO_DEBUG_ROUTE, "RTA %s (%c) WAS NOT CONNECTED TO %s (%c)\n",
297 HostP->Mapping[OldUnit-1].Name,OldLink+'A',
298 HostP->Mapping[ThisUnit-1].Name,ThisLink+'A');
299 }
300 }
301 if ( NewUnit == HOST_ID )
302 {
303 rio_dprintk (RIO_DEBUG_ROUTE, "MARKING HOST (%c) CONNECTED TO %s (%c)\n",
304 NewLink+'A',MyName,ThisLink+'A');
305 HostP->Topology[NewLink].Unit = ThisUnit;
306 HostP->Topology[NewLink].Link = ThisLink;
307 }
308 else if ( NewUnit <= MAX_RUP )
309 {
310 rio_dprintk (RIO_DEBUG_ROUTE, "MARKING RTA %s (%c) CONNECTED TO %s (%c)\n",
311 HostP->Mapping[NewUnit-1].Name,NewLink+'A',MyName,ThisLink+'A');
312 HostP->Mapping[NewUnit-1].Topology[NewLink].Unit=ThisUnit;
313 HostP->Mapping[NewUnit-1].Topology[NewLink].Link=ThisLink;
314 }
315 }
316 RIOSetChange(p);
317 RIOCheckIsolated(p, HostP, OldUnit );
318 }
319 }
320 return TRUE;
321 }
322
323 /*
324 ** The only other command we recognise is a route_request command
325 */
326 if ( RBYTE(PktCmdP->Command) != ROUTE_REQUEST )
327 {
328 rio_dprintk (RIO_DEBUG_ROUTE, "Unknown command %d received on rup %d host %d ROUTE_RUP\n",
329 RBYTE(PktCmdP->Command),Rup,(int)HostP);
330 return TRUE;
331 }
332
333 RtaUniq = (RBYTE(PktCmdP->UniqNum[0])) +
334 (RBYTE(PktCmdP->UniqNum[1]) << 8) +
335 (RBYTE(PktCmdP->UniqNum[2]) << 16) +
336 (RBYTE(PktCmdP->UniqNum[3]) << 24);
337
338 /*
339 ** Determine if 8 or 16 port RTA
340 */
341 RtaType = GetUnitType(RtaUniq);
342
343 rio_dprintk (RIO_DEBUG_ROUTE, "Received a request for an ID for serial number %x\n", RtaUniq);
344
345 Mod = RBYTE(PktCmdP->ModuleTypes);
346 Mod1 = LONYBLE(Mod);
347 if (RtaType == TYPE_RTA16)
348 {
349 /*
350 ** Only one ident is set for a 16 port RTA. To make compatible
351 ** with 8 port, set 2nd ident in Mod2 to the same as Mod1.
352 */
353 Mod2 = Mod1;
354 rio_dprintk (RIO_DEBUG_ROUTE, "Backplane type is %s (all ports)\n",
355 p->RIOModuleTypes[Mod1].Name);
356 }
357 else
358 {
359 Mod2 = HINYBLE(Mod);
360 rio_dprintk (RIO_DEBUG_ROUTE, "Module types are %s (ports 0-3) and %s (ports 4-7)\n",
361 p->RIOModuleTypes[Mod1].Name, p->RIOModuleTypes[Mod2].Name);
362 }
363
364 if ( RtaUniq == 0xffffffff )
365 {
366 ShowPacket( DBG_SPECIAL, PacketP );
367 }
368
369 /*
370 ** try to unhook a command block from the command free list.
371 */
372 if ( !(CmdBlkP = RIOGetCmdBlk()) )
373 {
374 rio_dprintk (RIO_DEBUG_ROUTE, "No command blocks to route RTA! come back later.\n");
375 return 0;
376 }
377
378 /*
379 ** Fill in the default info on the command block
380 */
381 CmdBlkP->Packet.dest_unit = Rup;
382 CmdBlkP->Packet.dest_port = ROUTE_RUP;
383 CmdBlkP->Packet.src_unit = HOST_ID;
384 CmdBlkP->Packet.src_port = ROUTE_RUP;
385 CmdBlkP->Packet.len = PKT_CMD_BIT | 1;
386 CmdBlkP->PreFuncP = CmdBlkP->PostFuncP = NULL;
387 PktReplyP = (struct PktCmd_M *)CmdBlkP->Packet.data;
388
389 if (! RIOBootOk(p, HostP, RtaUniq))
390 {
391 rio_dprintk (RIO_DEBUG_ROUTE, "RTA %x tried to get an ID, but does not belong - FOAD it!\n",
392 RtaUniq);
393 PktReplyP->Command = ROUTE_FOAD;
394 HostP->Copy("RT_FOAD", PktReplyP->CommandText, 7);
395 RIOQueueCmdBlk(HostP, Rup, CmdBlkP);
396 return TRUE;
397 }
398
399 /*
400 ** Check to see if the RTA is configured for this host
401 */
402 for ( ThisUnit=0; ThisUnit<MAX_RUP; ThisUnit++ )
403 {
404 rio_dprintk (RIO_DEBUG_ROUTE, "Entry %d Flags=%s %s UniqueNum=0x%x\n",
405 ThisUnit,
406 HostP->Mapping[ThisUnit].Flags & SLOT_IN_USE ?
407 "Slot-In-Use":"Not In Use",
408 HostP->Mapping[ThisUnit].Flags & SLOT_TENTATIVE ?
409 "Slot-Tentative":"Not Tentative",
410 HostP->Mapping[ThisUnit].RtaUniqueNum);
411
412 /*
413 ** We have an entry for it.
414 */
415 if ( (HostP->Mapping[ThisUnit].Flags & (SLOT_IN_USE | SLOT_TENTATIVE)) &&
416 (HostP->Mapping[ThisUnit].RtaUniqueNum == RtaUniq) )
417 {
418 if (RtaType == TYPE_RTA16)
419 {
420 ThisUnit2 = HostP->Mapping[ThisUnit].ID2 - 1;
421 rio_dprintk (RIO_DEBUG_ROUTE, "Found unit 0x%x at slots %d+%d\n",
422 RtaUniq,ThisUnit,ThisUnit2);
423 }
424 else
425 rio_dprintk (RIO_DEBUG_ROUTE, "Found unit 0x%x at slot %d\n",
426 RtaUniq,ThisUnit);
427 /*
428 ** If we have no knowledge of booting it, then the host has
429 ** been re-booted, and so we must kill the RTA, so that it
430 ** will be booted again (potentially with new bins)
431 ** and it will then re-ask for an ID, which we will service.
432 */
433 if ( (HostP->Mapping[ThisUnit].Flags & SLOT_IN_USE) &&
434 !(HostP->Mapping[ThisUnit].Flags & RTA_BOOTED) )
435 {
436 if ( !(HostP->Mapping[ThisUnit].Flags & MSG_DONE) )
437 {
438 if ( !p->RIONoMessage )
439 cprintf("RTA '%s' is being updated.\n",HostP->Mapping[ThisUnit].Name);
440 HostP->Mapping[ThisUnit].Flags |= MSG_DONE;
441 }
442 PktReplyP->Command = ROUTE_FOAD;
443 HostP->Copy("RT_FOAD",PktReplyP->CommandText,7);
444 RIOQueueCmdBlk(HostP, Rup, CmdBlkP);
445 return TRUE;
446 }
447
448 /*
449 ** Send the ID (entry) to this RTA. The ID number is implicit as
450 ** the offset into the table. It is worth noting at this stage
451 ** that offset zero in the table contains the entries for the
452 ** RTA with ID 1!!!!
453 */
454 PktReplyP->Command = ROUTE_ALLOCATE;
455 PktReplyP->IDNum = ThisUnit+1;
456 if (RtaType == TYPE_RTA16)
457 {
458 if (HostP->Mapping[ThisUnit].Flags & SLOT_IN_USE)
459 /*
460 ** Adjust the phb and tx pkt dest_units for 2nd block of 8
461 ** only if the RTA has ports associated (SLOT_IN_USE)
462 */
463 RIOFixPhbs(p, HostP, ThisUnit2);
464 PktReplyP->IDNum2 = ThisUnit2+1;
465 rio_dprintk (RIO_DEBUG_ROUTE, "RTA '%s' has been allocated IDs %d+%d\n",
466 HostP->Mapping[ThisUnit].Name, PktReplyP->IDNum, PktReplyP->IDNum2);
467 }
468 else
469 {
470 PktReplyP->IDNum2 = ROUTE_NO_ID;
471 rio_dprintk (RIO_DEBUG_ROUTE, "RTA '%s' has been allocated ID %d\n",
472 HostP->Mapping[ThisUnit].Name,PktReplyP->IDNum);
473 }
474 HostP->Copy("RT_ALLOCAT",PktReplyP->CommandText,10);
475
476 RIOQueueCmdBlk( HostP, Rup, CmdBlkP);
477
478 /*
479 ** If this is a freshly booted RTA, then we need to re-open
480 ** the ports, if any where open, so that data may once more
481 ** flow around the system!
482 */
483 if ( (HostP->Mapping[ThisUnit].Flags & RTA_NEWBOOT) &&
484 (HostP->Mapping[ThisUnit].SysPort != NO_PORT) )
485 {
486 /*
487 ** look at the ports associated with this beast and
488 ** see if any where open. If they was, then re-open
489 ** them, using the info from the tty flags.
490 */
491 for ( port=0; port<PORTS_PER_RTA; port++ )
492 {
493 PortP = p->RIOPortp[port+HostP->Mapping[ThisUnit].SysPort];
494 if ( PortP->State & (RIO_MOPEN|RIO_LOPEN) )
495 {
496 rio_dprintk (RIO_DEBUG_ROUTE, "Re-opened this port\n");
497 rio_spin_lock_irqsave(&PortP->portSem, flags);
498 PortP->MagicFlags |= MAGIC_REBOOT;
499 rio_spin_unlock_irqrestore(&PortP->portSem, flags);
500 }
501 }
502 if (RtaType == TYPE_RTA16)
503 {
504 for ( port=0; port<PORTS_PER_RTA; port++ )
505 {
506 PortP = p->RIOPortp[port+HostP->Mapping[ThisUnit2].SysPort];
507 if ( PortP->State & (RIO_MOPEN|RIO_LOPEN) )
508 {
509 rio_dprintk (RIO_DEBUG_ROUTE, "Re-opened this port\n");
510 rio_spin_lock_irqsave(&PortP->portSem, flags);
511 PortP->MagicFlags |= MAGIC_REBOOT;
512 rio_spin_unlock_irqrestore(&PortP->portSem, flags);
513 }
514 }
515 }
516 }
517
518 /*
519 ** keep a copy of the module types!
520 */
521 HostP->UnixRups[ThisUnit].ModTypes = Mod;
522 if (RtaType == TYPE_RTA16)
523 HostP->UnixRups[ThisUnit2].ModTypes = Mod;
524
525 /*
526 ** If either of the modules on this unit is read-only or write-only
527 ** or none-xprint, then we need to transfer that info over to the
528 ** relevant ports.
529 */
530 if ( HostP->Mapping[ThisUnit].SysPort != NO_PORT )
531 {
532 for ( port=0; port<PORTS_PER_MODULE; port++ )
533 {
534 p->RIOPortp[port+HostP->Mapping[ThisUnit].SysPort]->Config &= ~RIO_NOMASK;
535 p->RIOPortp[port+HostP->Mapping[ThisUnit].SysPort]->Config |=
536 p->RIOModuleTypes[Mod1].Flags[port];
537 p->RIOPortp[port+PORTS_PER_MODULE+HostP->Mapping[ThisUnit].SysPort]->Config &= ~RIO_NOMASK;
538 p->RIOPortp[port+PORTS_PER_MODULE+HostP->Mapping[ThisUnit].SysPort]->Config |= p->RIOModuleTypes[Mod2].Flags[port];
539 }
540 if (RtaType == TYPE_RTA16)
541 {
542 for ( port=0; port<PORTS_PER_MODULE; port++ )
543 {
544 p->RIOPortp[port+HostP->Mapping[ThisUnit2].SysPort]->Config &= ~RIO_NOMASK;
545 p->RIOPortp[port+HostP->Mapping[ThisUnit2].SysPort]->Config |= p->RIOModuleTypes[Mod1].Flags[port];
546 p->RIOPortp[port+PORTS_PER_MODULE+HostP->Mapping[ThisUnit2].SysPort]->Config &= ~RIO_NOMASK;
547 p->RIOPortp[port+PORTS_PER_MODULE+HostP->Mapping[ThisUnit2].SysPort]->Config |= p->RIOModuleTypes[Mod2].Flags[port];
548 }
549 }
550 }
551
552 /*
553 ** Job done, get on with the interrupts!
554 */
555 return TRUE;
556 }
557 }
558 /*
559 ** There is no table entry for this RTA at all.
560 **
561 ** Lets check to see if we actually booted this unit - if not,
562 ** then we reset it and it will go round the loop of being booted
563 ** we can then worry about trying to fit it into the table.
564 */
565 for ( ThisUnit=0; ThisUnit<HostP->NumExtraBooted; ThisUnit++ )
566 if ( HostP->ExtraUnits[ThisUnit] == RtaUniq )
567 break;
568 if ( ThisUnit == HostP->NumExtraBooted && ThisUnit != MAX_EXTRA_UNITS )
569 {
570 /*
571 ** if the unit wasn't in the table, and the table wasn't full, then
572 ** we reset the unit, because we didn't boot it.
573 ** However, if the table is full, it could be that we did boot
574 ** this unit, and so we won't reboot it, because it isn't really
575 ** all that disasterous to keep the old bins in most cases. This
576 ** is a rather tacky feature, but we are on the edge of reallity
577 ** here, because the implication is that someone has connected
578 ** 16+MAX_EXTRA_UNITS onto one host.
579 */
580 static int UnknownMesgDone = 0;
581
582 if ( !UnknownMesgDone )
583 {
584 if (! p->RIONoMessage)
585 cprintf("One or more unknown RTAs are being updated.\n");
586 UnknownMesgDone = 1;
587 }
588
589 PktReplyP->Command = ROUTE_FOAD;
590 HostP->Copy("RT_FOAD",PktReplyP->CommandText,7);
591 }
592 else
593 {
594 /*
595 ** we did boot it (as an extra), and there may now be a table
596 ** slot free (because of a delete), so we will try to make
597 ** a tentative entry for it, so that the configurator can see it
598 ** and fill in the details for us.
599 */
600 if (RtaType == TYPE_RTA16)
601 {
602 if (RIOFindFreeID(p, HostP, &ThisUnit, &ThisUnit2) == 0)
603 {
604 RIODefaultName(p, HostP, ThisUnit);
605 FillSlot(ThisUnit, ThisUnit2, RtaUniq, HostP);
606 }
607 }
608 else
609 {
610 if (RIOFindFreeID(p, HostP, &ThisUnit, NULL) == 0)
611 {
612 RIODefaultName(p, HostP, ThisUnit);
613 FillSlot(ThisUnit, 0, RtaUniq, HostP);
614 }
615 }
616 PktReplyP->Command = ROUTE_USED;
617 HostP->Copy("RT_USED",PktReplyP->CommandText,7);
618 }
619 RIOQueueCmdBlk( HostP, Rup, CmdBlkP);
620 return TRUE;
621}
622
623
624void
625RIOFixPhbs(p, HostP, unit)
626struct rio_info *p;
627struct Host *HostP;
628uint unit;
629{
630 ushort link, port;
631 struct Port *PortP;
632 unsigned long flags;
633 int PortN = HostP->Mapping[unit].SysPort;
634
635 rio_dprintk (RIO_DEBUG_ROUTE, "RIOFixPhbs unit %d sysport %d\n", unit, PortN);
636
637 if (PortN != -1) {
638 ushort dest_unit = HostP->Mapping[unit].ID2;
639
640 /*
641 ** Get the link number used for the 1st 8 phbs on this unit.
642 */
643 PortP = p->RIOPortp[HostP->Mapping[dest_unit - 1].SysPort];
644
645 link = RWORD(PortP->PhbP->link);
646
647 for (port = 0; port < PORTS_PER_RTA; port++, PortN++) {
648 ushort dest_port = port + 8;
649#if 0
650 uint PktInt;
651#endif
652 WORD *TxPktP;
653 PKT *Pkt;
654
655 PortP = p->RIOPortp[PortN];
656
657 rio_spin_lock_irqsave(&PortP->portSem, flags);
658 /*
659 ** If RTA is not powered on, the tx packets will be
660 ** unset, so go no further.
661 */
662 if (PortP->TxStart == 0) {
663 rio_dprintk (RIO_DEBUG_ROUTE, "Tx pkts not set up yet\n");
664 rio_spin_unlock_irqrestore(&PortP->portSem, flags);
665 break;
666 }
667
668 /*
669 ** For the second slot of a 16 port RTA, the driver needs to
670 ** sort out the phb to port mappings. The dest_unit for this
671 ** group of 8 phbs is set to the dest_unit of the accompanying
672 ** 8 port block. The dest_port of the second unit is set to
673 ** be in the range 8-15 (i.e. 8 is added). Thus, for a 16 port
674 ** RTA with IDs 5 and 6, traffic bound for port 6 of unit 6
675 ** (being the second map ID) will be sent to dest_unit 5, port
676 ** 14. When this RTA is deleted, dest_unit for ID 6 will be
677 ** restored, and the dest_port will be reduced by 8.
678 ** Transmit packets also have a destination field which needs
679 ** adjusting in the same manner.
680 ** Note that the unit/port bytes in 'dest' are swapped.
681 ** We also need to adjust the phb and rup link numbers for the
682 ** second block of 8 ttys.
683 */
684 for (TxPktP = PortP->TxStart; TxPktP <= PortP->TxEnd; TxPktP++) {
685 /*
686 ** *TxPktP is the pointer to the transmit packet on the host
687 ** card. This needs to be translated into a 32 bit pointer
688 ** so it can be accessed from the driver.
689 */
690 Pkt = (PKT *) RIO_PTR(HostP->Caddr,RINDW(TxPktP));
691
692 /*
693 ** If the packet is used, reset it.
694 */
695 Pkt = (PKT *)((uint)Pkt & ~PKT_IN_USE);
696 WBYTE(Pkt->dest_unit, dest_unit);
697 WBYTE(Pkt->dest_port, dest_port);
698 }
699 rio_dprintk (RIO_DEBUG_ROUTE, "phb dest: Old %x:%x New %x:%x\n",
700 RWORD(PortP->PhbP->destination) & 0xff,
701 (RWORD(PortP->PhbP->destination) >> 8) & 0xff,
702 dest_unit, dest_port);
703 WWORD(PortP->PhbP->destination, dest_unit + (dest_port << 8));
704 WWORD(PortP->PhbP->link, link);
705
706 rio_spin_unlock_irqrestore(&PortP->portSem, flags);
707 }
708 /*
709 ** Now make sure the range of ports to be serviced includes
710 ** the 2nd 8 on this 16 port RTA.
711 */
712 if (link > 3) return;
713 if (((unit * 8) + 7) > RWORD(HostP->LinkStrP[link].last_port)) {
714 rio_dprintk (RIO_DEBUG_ROUTE, "last port on host link %d: %d\n", link, (unit * 8) + 7);
715 WWORD(HostP->LinkStrP[link].last_port, (unit * 8) + 7);
716 }
717 }
718}
719
720/*
721** Check to see if the new disconnection has isolated this unit.
722** If it has, then invalidate all its link information, and tell
723** the world about it. This is done to ensure that the configurator
724** only gets up-to-date information about what is going on.
725*/
726static int
727RIOCheckIsolated(p, HostP, UnitId)
728struct rio_info * p;
729struct Host *HostP;
730uint UnitId;
731{
732 unsigned long flags;
733 rio_spin_lock_irqsave(&HostP->HostLock, flags);
734
735#ifdef CHECK
736 CheckHostP( HostP );
737 CheckUnitId( UnitId );
738#endif
739 if ( RIOCheck( HostP, UnitId ) ) {
740 rio_dprintk (RIO_DEBUG_ROUTE, "Unit %d is NOT isolated\n", UnitId);
741 rio_spin_unlock_irqrestore(&HostP->HostLock, flags);
742 return(0);
743 }
744
745 RIOIsolate(p, HostP, UnitId );
746 RIOSetChange(p);
747 rio_spin_unlock_irqrestore(&HostP->HostLock, flags);
748 return 1;
749}
750
751/*
752** Invalidate all the link interconnectivity of this unit, and of
753** all the units attached to it. This will mean that the entire
754** subnet will re-introduce itself.
755*/
756static int
757RIOIsolate(p, HostP, UnitId)
758struct rio_info * p;
759struct Host * HostP;
760uint UnitId;
761{
762 uint link, unit;
763
764#ifdef CHECK
765 CheckHostP( HostP );
766 CheckUnitId( UnitId );
767#endif
768 UnitId--; /* this trick relies on the Unit Id being UNSIGNED! */
769
770 if ( UnitId >= MAX_RUP ) /* dontcha just lurv unsigned maths! */
771 return(0);
772
773 if ( HostP->Mapping[UnitId].Flags & BEEN_HERE )
774 return(0);
775
776 HostP->Mapping[UnitId].Flags |= BEEN_HERE;
777
778 if ( p->RIOPrintDisabled == DO_PRINT )
779 rio_dprintk (RIO_DEBUG_ROUTE, "RIOMesgIsolated %s", HostP->Mapping[UnitId].Name);
780
781 for ( link=0; link<LINKS_PER_UNIT; link++) {
782 unit = HostP->Mapping[UnitId].Topology[link].Unit;
783 HostP->Mapping[UnitId].Topology[link].Unit = ROUTE_DISCONNECT;
784 HostP->Mapping[UnitId].Topology[link].Link = NO_LINK;
785 RIOIsolate(p, HostP, unit );
786 }
787 HostP->Mapping[UnitId].Flags &= ~BEEN_HERE;
788 return 1;
789}
790
791static int
792RIOCheck(HostP, UnitId)
793struct Host *HostP;
794uint UnitId;
795{
796 unsigned char link;
797
798#ifdef CHECK
799 CheckHostP( HostP );
800 CheckUnitId( UnitId );
801#endif
802/* rio_dprint(RIO_DEBUG_ROUTE, ("Check to see if unit %d has a route to the host\n",UnitId)); */
803 rio_dprintk (RIO_DEBUG_ROUTE, "RIOCheck : UnitID = %d\n", UnitId);
804
805 if ( UnitId == HOST_ID ) {
806 /* rio_dprint(RIO_DEBUG_ROUTE, ("Unit %d is NOT isolated - it IS the host!\n", UnitId)); */
807 return 1;
808 }
809
810 UnitId--;
811
812 if ( UnitId >= MAX_RUP ) {
813 /* rio_dprint(RIO_DEBUG_ROUTE, ("Unit %d - ignored.\n", UnitId)); */
814 return 0;
815 }
816
817 for ( link=0; link<LINKS_PER_UNIT; link++ ) {
818 if ( HostP->Mapping[UnitId].Topology[link].Unit==HOST_ID ) {
819 /* rio_dprint(RIO_DEBUG_ROUTE, ("Unit %d is connected directly to host via link (%c).\n",
820 UnitId, 'A'+link)); */
821 return 1;
822 }
823 }
824
825 if ( HostP->Mapping[UnitId].Flags & BEEN_HERE ) {
826 /* rio_dprint(RIO_DEBUG_ROUTE, ("Been to Unit %d before - ignoring\n", UnitId)); */
827 return 0;
828 }
829
830 HostP->Mapping[UnitId].Flags |= BEEN_HERE;
831
832 for ( link=0; link < LINKS_PER_UNIT; link++ ) {
833 /* rio_dprint(RIO_DEBUG_ROUTE, ("Unit %d check link (%c)\n", UnitId,'A'+link)); */
834 if ( RIOCheck( HostP, HostP->Mapping[UnitId].Topology[link].Unit ) ) {
835 /* rio_dprint(RIO_DEBUG_ROUTE, ("Unit %d is connected to something that knows the host via link (%c)\n", UnitId,link+'A')); */
836 HostP->Mapping[UnitId].Flags &= ~BEEN_HERE;
837 return 1;
838 }
839 }
840
841 HostP->Mapping[UnitId].Flags &= ~BEEN_HERE;
842
843 /* rio_dprint(RIO_DEBUG_ROUTE, ("Unit %d DOESNT KNOW THE HOST!\n", UnitId)); */
844
845 return 0;
846}
847
848/*
849** Returns the type of unit (host, 16/8 port RTA)
850*/
851
852uint
853GetUnitType(Uniq)
854uint Uniq;
855{
856 switch ( (Uniq >> 28) & 0xf)
857 {
858 case RIO_AT:
859 case RIO_MCA:
860 case RIO_EISA:
861 case RIO_PCI:
862 rio_dprintk (RIO_DEBUG_ROUTE, "Unit type: Host\n");
863 return(TYPE_HOST);
864 case RIO_RTA_16:
865 rio_dprintk (RIO_DEBUG_ROUTE, "Unit type: 16 port RTA\n");
866 return(TYPE_RTA16);
867 case RIO_RTA:
868 rio_dprintk (RIO_DEBUG_ROUTE, "Unit type: 8 port RTA\n");
869 return(TYPE_RTA8);
870 default :
871 rio_dprintk (RIO_DEBUG_ROUTE, "Unit type: Unrecognised\n");
872 return(99);
873 }
874}
875
876int
877RIOSetChange(p)
878struct rio_info * p;
879{
880 if ( p->RIOQuickCheck != NOT_CHANGED )
881 return(0);
882 p->RIOQuickCheck = CHANGED;
883 if ( p->RIOSignalProcess ) {
884 rio_dprintk (RIO_DEBUG_ROUTE, "Send SIG-HUP");
885 /*
886 psignal( RIOSignalProcess, SIGHUP );
887 */
888 }
889 return(0);
890}
891
892static void
893RIOConCon(p, HostP, FromId, FromLink, ToId, ToLink, Change)
894struct rio_info * p;
895struct Host *HostP;
896uint FromId;
897uint FromLink;
898uint ToId;
899uint ToLink;
900int Change;
901{
902 char *FromName;
903 char *FromType;
904 char *ToName;
905 char *ToType;
906 unsigned int tp;
907
908/*
909** 15.10.1998 ARG - ESIL 0759
910** (Part) fix for port being trashed when opened whilst RTA "disconnected"
911**
912** What's this doing in here anyway ?
913** It was causing the port to be 'unmapped' if opened whilst RTA "disconnected"
914**
915** 09.12.1998 ARG - ESIL 0776 - part fix
916** Okay, We've found out what this was all about now !
917** Someone had botched this to use RIOHalted to indicated the number of RTAs
918** 'disconnected'. The value in RIOHalted was then being used in the
919** 'RIO_QUICK_CHECK' ioctl. A none zero value indicating that a least one RTA
920** is 'disconnected'. The change was put in to satisfy a customer's needs.
921** Having taken this bit of code out 'RIO_QUICK_CHECK' now no longer works for
922** the customer.
923**
924 if (Change == CONNECT) {
925 if (p->RIOHalted) p->RIOHalted --;
926 }
927 else {
928 p->RIOHalted ++;
929 }
930**
931** So - we need to implement it slightly differently - a new member of the
932** rio_info struct - RIORtaDisCons (RIO RTA connections) keeps track of RTA
933** connections and disconnections.
934*/
935 if (Change == CONNECT) {
936 if (p->RIORtaDisCons) p->RIORtaDisCons--;
937 }
938 else {
939 p->RIORtaDisCons++;
940 }
941
942 if ( p->RIOPrintDisabled == DONT_PRINT )
943 return;
944
945 if ( FromId > ToId ) {
946 tp = FromId;
947 FromId = ToId;
948 ToId = tp;
949 tp = FromLink;
950 FromLink = ToLink;
951 ToLink = tp;
952 }
953
954 FromName = FromId ? HostP->Mapping[FromId-1].Name : HostP->Name;
955 FromType = FromId ? "RTA" : "HOST";
956 ToName = ToId ? HostP->Mapping[ToId-1].Name : HostP->Name;
957 ToType = ToId ? "RTA" : "HOST";
958
959 rio_dprintk (RIO_DEBUG_ROUTE, "Link between %s '%s' (%c) and %s '%s' (%c) %s.\n",
960 FromType, FromName, 'A'+FromLink,
961 ToType, ToName, 'A'+ToLink,
962 (Change==CONNECT) ? "established" : "disconnected");
963 cprintf("Link between %s '%s' (%c) and %s '%s' (%c) %s.\n",
964 FromType, FromName, 'A'+FromLink,
965 ToType, ToName, 'A'+ToLink,
966 (Change==CONNECT) ? "established" : "disconnected");
967}
968
969/*
970** RIORemoveFromSavedTable :
971**
972** Delete and RTA entry from the saved table given to us
973** by the configuration program.
974*/
975static int
976RIORemoveFromSavedTable(struct rio_info *p, struct Map *pMap)
977{
978 int entry;
979
980 /*
981 ** We loop for all entries even after finding an entry and
982 ** zeroing it because we may have two entries to delete if
983 ** it's a 16 port RTA.
984 */
985 for (entry = 0; entry < TOTAL_MAP_ENTRIES; entry++)
986 {
987 if (p->RIOSavedTable[entry].RtaUniqueNum == pMap->RtaUniqueNum)
988 {
989 bzero((caddr_t)&p->RIOSavedTable[entry], sizeof(struct Map));
990 }
991 }
992 return 0;
993}
994
995
996/*
997** RIOCheckDisconnected :
998**
999** Scan the unit links to and return zero if the unit is completely
1000** disconnected.
1001*/
1002static int
1003RIOFreeDisconnected(struct rio_info *p, struct Host *HostP, int unit)
1004{
1005 int link;
1006
1007
1008 rio_dprintk (RIO_DEBUG_ROUTE, "RIOFreeDisconnect unit %d\n", unit);
1009 /*
1010 ** If the slot is tentative and does not belong to the
1011 ** second half of a 16 port RTA then scan to see if
1012 ** is disconnected.
1013 */
1014 for (link = 0; link < LINKS_PER_UNIT; link++)
1015 {
1016 if (HostP->Mapping[unit].Topology[link].Unit != ROUTE_DISCONNECT)
1017 break;
1018 }
1019
1020 /*
1021 ** If not all links are disconnected then we can forget about it.
1022 */
1023 if (link < LINKS_PER_UNIT)
1024 return 1;
1025
1026#if NEED_TO_FIX_THIS
1027 /* Ok so all the links are disconnected. But we may have only just
1028 ** made this slot tentative and not yet received a topology update.
1029 ** Lets check how long ago we made it tentative.
1030 */
1031 rio_dprintk (RIO_DEBUG_ROUTE, "Just about to check LBOLT on entry %d\n", unit);
1032 if (drv_getparm(LBOLT, (ulong_t *) &current_time))
1033 rio_dprintk (RIO_DEBUG_ROUTE, "drv_getparm(LBOLT,....) Failed.\n");
1034
1035 elapse_time = current_time - TentTime[unit];
1036 rio_dprintk (RIO_DEBUG_ROUTE, "elapse %d = current %d - tent %d (%d usec)\n",
1037 elapse_time, current_time, TentTime[unit], drv_hztousec(elapse_time));
1038 if (drv_hztousec(elapse_time) < WAIT_TO_FINISH)
1039 {
1040 rio_dprintk (RIO_DEBUG_ROUTE, "Skipping slot %d, not timed out yet %d\n",
1041 unit, drv_hztousec(elapse_time));
1042 return 1;
1043 }
1044#endif
1045
1046 /*
1047 ** We have found an usable slot.
1048 ** If it is half of a 16 port RTA then delete the other half.
1049 */
1050 if (HostP->Mapping[unit].ID2 != 0)
1051 {
1052 int nOther = (HostP->Mapping[unit].ID2) -1;
1053
1054 rio_dprintk (RIO_DEBUG_ROUTE, "RioFreedis second slot %d.\n", nOther);
1055 bzero((caddr_t)&HostP->Mapping[nOther], sizeof(struct Map));
1056 }
1057 RIORemoveFromSavedTable(p, &HostP->Mapping[unit]);
1058
1059 return 0;
1060}
1061
1062
1063/*
1064** RIOFindFreeID :
1065**
1066** This function scans the given host table for either one
1067** or two free unit ID's.
1068*/
1069int
1070RIOFindFreeID(struct rio_info *p, struct Host *HostP, uint *pID1, uint *pID2)
1071{
1072 int unit,tempID;
1073
1074 /*
1075 ** Initialise the ID's to MAX_RUP.
1076 ** We do this to make the loop for setting the ID's as simple as
1077 ** possible.
1078 */
1079 *pID1 = MAX_RUP;
1080 if (pID2 != NULL)
1081 *pID2 = MAX_RUP;
1082
1083 /*
1084 ** Scan all entries of the host mapping table for free slots.
1085 ** We scan for free slots first and then if that is not successful
1086 ** we start all over again looking for tentative slots we can re-use.
1087 */
1088 for (unit = 0; unit < MAX_RUP; unit++)
1089 {
1090 rio_dprintk (RIO_DEBUG_ROUTE, "Scanning unit %d\n",unit);
1091 /*
1092 ** If the flags are zero then the slot is empty.
1093 */
1094 if (HostP->Mapping[unit].Flags == 0)
1095 {
1096 rio_dprintk (RIO_DEBUG_ROUTE, " This slot is empty.\n");
1097 /*
1098 ** If we haven't allocated the first ID then do it now.
1099 */
1100 if (*pID1 == MAX_RUP)
1101 {
1102 rio_dprintk (RIO_DEBUG_ROUTE, "Make tentative entry for first unit %d\n", unit);
1103 *pID1 = unit;
1104
1105 /*
1106 ** If the second ID is not needed then we can return
1107 ** now.
1108 */
1109 if (pID2 == NULL)
1110 return 0;
1111 }
1112 else
1113 {
1114 /*
1115 ** Allocate the second slot and return.
1116 */
1117 rio_dprintk (RIO_DEBUG_ROUTE, "Make tentative entry for second unit %d\n", unit);
1118 *pID2 = unit;
1119 return 0;
1120 }
1121 }
1122 }
1123
1124 /*
1125 ** If we manage to come out of the free slot loop then we
1126 ** need to start all over again looking for tentative slots
1127 ** that we can re-use.
1128 */
1129 rio_dprintk (RIO_DEBUG_ROUTE, "Starting to scan for tentative slots\n");
1130 for (unit = 0; unit < MAX_RUP; unit++)
1131 {
1132 if (((HostP->Mapping[unit].Flags & SLOT_TENTATIVE) ||
1133 (HostP->Mapping[unit].Flags == 0)) && !
1134 (HostP->Mapping[unit].Flags & RTA16_SECOND_SLOT ))
1135 {
1136 rio_dprintk (RIO_DEBUG_ROUTE, " Slot %d looks promising.\n",unit);
1137
1138 if(unit == *pID1)
1139 {
1140 rio_dprintk (RIO_DEBUG_ROUTE, " No it isn't, its the 1st half\n");
1141 continue;
1142 }
1143
1144 /*
1145 ** Slot is Tentative or Empty, but not a tentative second
1146 ** slot of a 16 porter.
1147 ** Attempt to free up this slot (and its parnter if
1148 ** it is a 16 port slot. The second slot will become
1149 ** empty after a call to RIOFreeDisconnected so thats why
1150 ** we look for empty slots above as well).
1151 */
1152 if (HostP->Mapping[unit].Flags != 0)
1153 if (RIOFreeDisconnected(p, HostP, unit) != 0)
1154 continue;
1155 /*
1156 ** If we haven't allocated the first ID then do it now.
1157 */
1158 if (*pID1 == MAX_RUP)
1159 {
1160 rio_dprintk (RIO_DEBUG_ROUTE, "Grab tentative entry for first unit %d\n", unit);
1161 *pID1 = unit;
1162
1163 /*
1164 ** Clear out this slot now that we intend to use it.
1165 */
1166 bzero(&HostP->Mapping[unit], sizeof(struct Map));
1167
1168 /*
1169 ** If the second ID is not needed then we can return
1170 ** now.
1171 */
1172 if (pID2 == NULL)
1173 return 0;
1174 }
1175 else
1176 {
1177 /*
1178 ** Allocate the second slot and return.
1179 */
1180 rio_dprintk (RIO_DEBUG_ROUTE, "Grab tentative/empty entry for second unit %d\n",
1181 unit);
1182 *pID2 = unit;
1183
1184 /*
1185 ** Clear out this slot now that we intend to use it.
1186 */
1187 bzero(&HostP->Mapping[unit], sizeof(struct Map));
1188
1189 /* At this point under the right(wrong?) conditions
1190 ** we may have a first unit ID being higher than the
1191 ** second unit ID. This is a bad idea if we are about
1192 ** to fill the slots with a 16 port RTA.
1193 ** Better check and swap them over.
1194 */
1195
1196 if (*pID1 > *pID2)
1197 {
1198 rio_dprintk (RIO_DEBUG_ROUTE, "Swapping IDS %d %d\n", *pID1, *pID2);
1199 tempID = *pID1;
1200 *pID1 = *pID2;
1201 *pID2 = tempID;
1202 }
1203 return 0;
1204 }
1205 }
1206 }
1207
1208 /*
1209 ** If we manage to get to the end of the second loop then we
1210 ** can give up and return a failure.
1211 */
1212 return 1;
1213}
1214
1215
1216/*
1217** The link switch scenario.
1218**
1219** Rta Wun (A) is connected to Tuw (A).
1220** The tables are all up to date, and the system is OK.
1221**
1222** If Wun (A) is now moved to Wun (B) before Wun (A) can
1223** become disconnected, then the follow happens:
1224**
1225** Tuw (A) spots the change of unit:link at the other end
1226** of its link and Tuw sends a topology packet reflecting
1227** the change: Tuw (A) now disconnected from Wun (A), and
1228** this is closely followed by a packet indicating that
1229** Tuw (A) is now connected to Wun (B).
1230**
1231** Wun (B) will spot that it has now become connected, and
1232** Wun will send a topology packet, which indicates that
1233** both Wun (A) and Wun (B) is connected to Tuw (A).
1234**
1235** Eventually Wun (A) realises that it is now disconnected
1236** and Wun will send out a topology packet indicating that
1237** Wun (A) is now disconnected.
1238*/