xref: /openbmc/linux/drivers/net/fddi/skfp/cfm.c (revision 3cf3cdea)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /******************************************************************************
3  *
4  *	(C)Copyright 1998,1999 SysKonnect,
5  *	a business unit of Schneider & Koch & Co. Datensysteme GmbH.
6  *
7  *	See the file "skfddi.c" for further information.
8  *
9  *	The information in this file is provided "AS IS" without warranty.
10  *
11  ******************************************************************************/
12 
13 /*
14 	SMT CFM
15 	Configuration Management
16 	DAS with single MAC
17 */
18 
19 /*
20  *	Hardware independent state machine implemantation
21  *	The following external SMT functions are referenced :
22  *
23  *		queue_event()
24  *
25  *	The following external HW dependent functions are referenced :
26  *		config_mux()
27  *
28  *	The following HW dependent events are required :
29  *		NONE
30  */
31 
32 #include "h/types.h"
33 #include "h/fddi.h"
34 #include "h/smc.h"
35 
36 #define KERNEL
37 #include "h/smtstate.h"
38 
39 /*
40  * FSM Macros
41  */
42 #define AFLAG	0x10
43 #define GO_STATE(x)	(smc->mib.fddiSMTCF_State = (x)|AFLAG)
44 #define ACTIONS_DONE()	(smc->mib.fddiSMTCF_State &= ~AFLAG)
45 #define ACTIONS(x)	(x|AFLAG)
46 
47 /*
48  * symbolic state names
49  */
50 static const char * const cfm_states[] = {
51 	"SC0_ISOLATED","CF1","CF2","CF3","CF4",
52 	"SC1_WRAP_A","SC2_WRAP_B","SC5_TRHU_B","SC7_WRAP_S",
53 	"SC9_C_WRAP_A","SC10_C_WRAP_B","SC11_C_WRAP_S","SC4_THRU_A"
54 } ;
55 
56 /*
57  * symbolic event names
58  */
59 static const char * const cfm_events[] = {
60 	"NONE","CF_LOOP_A","CF_LOOP_B","CF_JOIN_A","CF_JOIN_B"
61 } ;
62 
63 /*
64  * map from state to downstream port type
65  */
66 static const unsigned char cf_to_ptype[] = {
67 	TNONE,TNONE,TNONE,TNONE,TNONE,
68 	TNONE,TB,TB,TS,
69 	TA,TB,TS,TB
70 } ;
71 
72 /*
73  * CEM port states
74  */
75 #define	CEM_PST_DOWN	0
76 #define	CEM_PST_UP	1
77 #define	CEM_PST_HOLD	2
78 /* define portstate array only for A and B port */
79 /* Do this within the smc structure (use in multiple cards) */
80 
81 /*
82  * all Globals  are defined in smc.h
83  * struct s_cfm
84  */
85 
86 /*
87  * function declarations
88  */
89 static void cfm_fsm(struct s_smc *smc, int cmd);
90 
91 /*
92 	init CFM state machine
93 	clear all CFM vars and flags
94 */
95 void cfm_init(struct s_smc *smc)
96 {
97 	smc->mib.fddiSMTCF_State = ACTIONS(SC0_ISOLATED) ;
98 	smc->r.rm_join = 0 ;
99 	smc->r.rm_loop = 0 ;
100 	smc->y[PA].scrub = 0 ;
101 	smc->y[PB].scrub = 0 ;
102 	smc->y[PA].cem_pst = CEM_PST_DOWN ;
103 	smc->y[PB].cem_pst = CEM_PST_DOWN ;
104 }
105 
106 /* Some terms conditions used by the selection criteria */
107 #define THRU_ENABLED(smc)	(smc->y[PA].pc_mode != PM_TREE && \
108 				 smc->y[PB].pc_mode != PM_TREE)
109 /* Selection criteria for the ports */
110 static void selection_criteria (struct s_smc *smc, struct s_phy *phy)
111 {
112 
113 	switch (phy->mib->fddiPORTMy_Type) {
114 	case TA:
115 		if ( !THRU_ENABLED(smc) && smc->y[PB].cf_join ) {
116 			phy->wc_flag = TRUE ;
117 		} else {
118 			phy->wc_flag = FALSE ;
119 		}
120 
121 		break;
122 	case TB:
123 		/* take precedence over PA */
124 		phy->wc_flag = FALSE ;
125 		break;
126 	case TS:
127 		phy->wc_flag = FALSE ;
128 		break;
129 	case TM:
130 		phy->wc_flag = FALSE ;
131 		break;
132 	}
133 
134 }
135 
136 void all_selection_criteria(struct s_smc *smc)
137 {
138 	struct s_phy	*phy ;
139 	int		p ;
140 
141 	for ( p = 0,phy = smc->y ; p < NUMPHYS; p++, phy++ ) {
142 		/* Do the selection criteria */
143 		selection_criteria (smc,phy);
144 	}
145 }
146 
147 static void cem_priv_state(struct s_smc *smc, int event)
148 /* State machine for private PORT states: used to optimize dual homing */
149 {
150 	int	np;	/* Number of the port */
151 	int	i;
152 
153 	/* Do this only in a DAS */
154 	if (smc->s.sas != SMT_DAS )
155 		return ;
156 
157 	np = event - CF_JOIN;
158 
159 	if (np != PA && np != PB) {
160 		return ;
161 	}
162 	/* Change the port state according to the event (portnumber) */
163 	if (smc->y[np].cf_join) {
164 		smc->y[np].cem_pst = CEM_PST_UP ;
165 	} else if (!smc->y[np].wc_flag) {
166 		/* set the port to done only if it is not withheld */
167 		smc->y[np].cem_pst = CEM_PST_DOWN ;
168 	}
169 
170 	/* Don't set an hold port to down */
171 
172 	/* Check all ports of restart conditions */
173 	for (i = 0 ; i < 2 ; i ++ ) {
174 		/* Check all port for PORT is on hold and no withhold is done */
175 		if ( smc->y[i].cem_pst == CEM_PST_HOLD && !smc->y[i].wc_flag ) {
176 			smc->y[i].cem_pst = CEM_PST_DOWN;
177 			queue_event(smc,(int)(EVENT_PCM+i),PC_START) ;
178 		}
179 		if ( smc->y[i].cem_pst == CEM_PST_UP && smc->y[i].wc_flag ) {
180 			smc->y[i].cem_pst = CEM_PST_HOLD;
181 			queue_event(smc,(int)(EVENT_PCM+i),PC_START) ;
182 		}
183 		if ( smc->y[i].cem_pst == CEM_PST_DOWN && smc->y[i].wc_flag ) {
184 			/*
185 			 * The port must be restarted when the wc_flag
186 			 * will be reset. So set the port on hold.
187 			 */
188 			smc->y[i].cem_pst = CEM_PST_HOLD;
189 		}
190 	}
191 	return ;
192 }
193 
194 /*
195 	CFM state machine
196 	called by dispatcher
197 
198 	do
199 		display state change
200 		process event
201 	until SM is stable
202 */
203 void cfm(struct s_smc *smc, int event)
204 {
205 	int	state ;		/* remember last state */
206 	int	cond ;
207 
208 	/* We will do the following: */
209 	/*  - compute the variable WC_Flag for every port (This is where */
210 	/*    we can extend the requested path checking !!) */
211 	/*  - do the old (SMT 6.2 like) state machine */
212 	/*  - do the resulting station states */
213 
214 	all_selection_criteria (smc);
215 
216 	/* We will check now whether a state transition is allowed or not */
217 	/*  - change the portstates */
218 	cem_priv_state (smc, event);
219 
220 	do {
221 		DB_CFM("CFM : state %s%s event %s",
222 		       smc->mib.fddiSMTCF_State & AFLAG ? "ACTIONS " : "",
223 		       cfm_states[smc->mib.fddiSMTCF_State & ~AFLAG],
224 		       cfm_events[event]);
225 		state = smc->mib.fddiSMTCF_State ;
226 		cfm_fsm(smc,event) ;
227 		event = 0 ;
228 	} while (state != smc->mib.fddiSMTCF_State) ;
229 
230 #ifndef	SLIM_SMT
231 	/*
232 	 * check peer wrap condition
233 	 */
234 	cond = FALSE ;
235 	if (	(smc->mib.fddiSMTCF_State == SC9_C_WRAP_A &&
236 		smc->y[PA].pc_mode == PM_PEER) 	||
237 		(smc->mib.fddiSMTCF_State == SC10_C_WRAP_B &&
238 		smc->y[PB].pc_mode == PM_PEER) 	||
239 		(smc->mib.fddiSMTCF_State == SC11_C_WRAP_S &&
240 		smc->y[PS].pc_mode == PM_PEER &&
241 		smc->y[PS].mib->fddiPORTNeighborType != TS ) ) {
242 			cond = TRUE ;
243 	}
244 	if (cond != smc->mib.fddiSMTPeerWrapFlag)
245 		smt_srf_event(smc,SMT_COND_SMT_PEER_WRAP,0,cond) ;
246 
247 	/*
248 	 * Don't ever send MAC_PATH_CHANGE events. Our MAC is hard-wired
249 	 * to the primary path.
250 	 */
251 
252 #endif	/* no SLIM_SMT */
253 
254 	/*
255 	 * set MAC port type
256 	 */
257 	smc->mib.m[MAC0].fddiMACDownstreamPORTType =
258 		cf_to_ptype[smc->mib.fddiSMTCF_State] ;
259 	cfm_state_change(smc,(int)smc->mib.fddiSMTCF_State) ;
260 }
261 
262 /*
263 	process CFM event
264 */
265 /*ARGSUSED1*/
266 static void cfm_fsm(struct s_smc *smc, int cmd)
267 {
268 	switch(smc->mib.fddiSMTCF_State) {
269 	case ACTIONS(SC0_ISOLATED) :
270 		smc->mib.p[PA].fddiPORTCurrentPath = MIB_PATH_ISOLATED ;
271 		smc->mib.p[PB].fddiPORTCurrentPath = MIB_PATH_ISOLATED ;
272 		smc->mib.p[PA].fddiPORTMACPlacement = 0 ;
273 		smc->mib.p[PB].fddiPORTMACPlacement = 0 ;
274 		smc->mib.fddiSMTStationStatus = MIB_SMT_STASTA_SEPA ;
275 		config_mux(smc,MUX_ISOLATE) ;	/* configure PHY Mux */
276 		smc->r.rm_loop = FALSE ;
277 		smc->r.rm_join = FALSE ;
278 		queue_event(smc,EVENT_RMT,RM_JOIN) ;/* signal RMT */
279 		/* Don't do the WC-Flag changing here */
280 		ACTIONS_DONE() ;
281 		DB_CFMN(1, "CFM : %s", cfm_states[smc->mib.fddiSMTCF_State]);
282 		break;
283 	case SC0_ISOLATED :
284 		/*SC07*/
285 		/*SAS port can be PA or PB ! */
286 		if (smc->s.sas && (smc->y[PA].cf_join || smc->y[PA].cf_loop ||
287 				smc->y[PB].cf_join || smc->y[PB].cf_loop)) {
288 			GO_STATE(SC11_C_WRAP_S) ;
289 			break ;
290 		}
291 		/*SC01*/
292 		if ((smc->y[PA].cem_pst == CEM_PST_UP && smc->y[PA].cf_join &&
293 		     !smc->y[PA].wc_flag) || smc->y[PA].cf_loop) {
294 			GO_STATE(SC9_C_WRAP_A) ;
295 			break ;
296 		}
297 		/*SC02*/
298 		if ((smc->y[PB].cem_pst == CEM_PST_UP && smc->y[PB].cf_join &&
299 		     !smc->y[PB].wc_flag) || smc->y[PB].cf_loop) {
300 			GO_STATE(SC10_C_WRAP_B) ;
301 			break ;
302 		}
303 		break ;
304 	case ACTIONS(SC9_C_WRAP_A) :
305 		smc->mib.p[PA].fddiPORTCurrentPath = MIB_PATH_CONCATENATED ;
306 		smc->mib.p[PB].fddiPORTCurrentPath = MIB_PATH_ISOLATED ;
307 		smc->mib.p[PA].fddiPORTMACPlacement = INDEX_MAC ;
308 		smc->mib.p[PB].fddiPORTMACPlacement = 0 ;
309 		smc->mib.fddiSMTStationStatus = MIB_SMT_STASTA_CON ;
310 		config_mux(smc,MUX_WRAPA) ;		/* configure PHY mux */
311 		if (smc->y[PA].cf_loop) {
312 			smc->r.rm_join = FALSE ;
313 			smc->r.rm_loop = TRUE ;
314 			queue_event(smc,EVENT_RMT,RM_LOOP) ;/* signal RMT */
315 		}
316 		if (smc->y[PA].cf_join) {
317 			smc->r.rm_loop = FALSE ;
318 			smc->r.rm_join = TRUE ;
319 			queue_event(smc,EVENT_RMT,RM_JOIN) ;/* signal RMT */
320 		}
321 		ACTIONS_DONE() ;
322 		DB_CFMN(1, "CFM : %s", cfm_states[smc->mib.fddiSMTCF_State]);
323 		break ;
324 	case SC9_C_WRAP_A :
325 		/*SC10*/
326 		if ( (smc->y[PA].wc_flag || !smc->y[PA].cf_join) &&
327 		      !smc->y[PA].cf_loop ) {
328 			GO_STATE(SC0_ISOLATED) ;
329 			break ;
330 		}
331 		/*SC12*/
332 		else if ( (smc->y[PB].cf_loop && smc->y[PA].cf_join &&
333 			   smc->y[PA].cem_pst == CEM_PST_UP) ||
334 			  ((smc->y[PB].cf_loop ||
335 			   (smc->y[PB].cf_join &&
336 			    smc->y[PB].cem_pst == CEM_PST_UP)) &&
337 			    (smc->y[PA].pc_mode == PM_TREE ||
338 			     smc->y[PB].pc_mode == PM_TREE))) {
339 			smc->y[PA].scrub = TRUE ;
340 			GO_STATE(SC10_C_WRAP_B) ;
341 			break ;
342 		}
343 		/*SC14*/
344 		else if (!smc->s.attach_s &&
345 			  smc->y[PA].cf_join &&
346 			  smc->y[PA].cem_pst == CEM_PST_UP &&
347 			  smc->y[PA].pc_mode == PM_PEER && smc->y[PB].cf_join &&
348 			  smc->y[PB].cem_pst == CEM_PST_UP &&
349 			  smc->y[PB].pc_mode == PM_PEER) {
350 			smc->y[PA].scrub = TRUE ;
351 			smc->y[PB].scrub = TRUE ;
352 			GO_STATE(SC4_THRU_A) ;
353 			break ;
354 		}
355 		/*SC15*/
356 		else if ( smc->s.attach_s &&
357 			  smc->y[PA].cf_join &&
358 			  smc->y[PA].cem_pst == CEM_PST_UP &&
359 			  smc->y[PA].pc_mode == PM_PEER &&
360 			  smc->y[PB].cf_join &&
361 			  smc->y[PB].cem_pst == CEM_PST_UP &&
362 			  smc->y[PB].pc_mode == PM_PEER) {
363 			smc->y[PA].scrub = TRUE ;
364 			smc->y[PB].scrub = TRUE ;
365 			GO_STATE(SC5_THRU_B) ;
366 			break ;
367 		}
368 		break ;
369 	case ACTIONS(SC10_C_WRAP_B) :
370 		smc->mib.p[PA].fddiPORTCurrentPath = MIB_PATH_ISOLATED ;
371 		smc->mib.p[PB].fddiPORTCurrentPath = MIB_PATH_CONCATENATED ;
372 		smc->mib.p[PA].fddiPORTMACPlacement = 0 ;
373 		smc->mib.p[PB].fddiPORTMACPlacement = INDEX_MAC ;
374 		smc->mib.fddiSMTStationStatus = MIB_SMT_STASTA_CON ;
375 		config_mux(smc,MUX_WRAPB) ;		/* configure PHY mux */
376 		if (smc->y[PB].cf_loop) {
377 			smc->r.rm_join = FALSE ;
378 			smc->r.rm_loop = TRUE ;
379 			queue_event(smc,EVENT_RMT,RM_LOOP) ;/* signal RMT */
380 		}
381 		if (smc->y[PB].cf_join) {
382 			smc->r.rm_loop = FALSE ;
383 			smc->r.rm_join = TRUE ;
384 			queue_event(smc,EVENT_RMT,RM_JOIN) ;/* signal RMT */
385 		}
386 		ACTIONS_DONE() ;
387 		DB_CFMN(1, "CFM : %s", cfm_states[smc->mib.fddiSMTCF_State]);
388 		break ;
389 	case SC10_C_WRAP_B :
390 		/*SC20*/
391 		if ( !smc->y[PB].cf_join && !smc->y[PB].cf_loop ) {
392 			GO_STATE(SC0_ISOLATED) ;
393 			break ;
394 		}
395 		/*SC21*/
396 		else if ( smc->y[PA].cf_loop && smc->y[PA].pc_mode == PM_PEER &&
397 			  smc->y[PB].cf_join && smc->y[PB].pc_mode == PM_PEER) {
398 			smc->y[PB].scrub = TRUE ;
399 			GO_STATE(SC9_C_WRAP_A) ;
400 			break ;
401 		}
402 		/*SC24*/
403 		else if (!smc->s.attach_s &&
404 			 smc->y[PA].cf_join && smc->y[PA].pc_mode == PM_PEER &&
405 			 smc->y[PB].cf_join && smc->y[PB].pc_mode == PM_PEER) {
406 			smc->y[PA].scrub = TRUE ;
407 			smc->y[PB].scrub = TRUE ;
408 			GO_STATE(SC4_THRU_A) ;
409 			break ;
410 		}
411 		/*SC25*/
412 		else if ( smc->s.attach_s &&
413 			 smc->y[PA].cf_join && smc->y[PA].pc_mode == PM_PEER &&
414 			 smc->y[PB].cf_join && smc->y[PB].pc_mode == PM_PEER) {
415 			smc->y[PA].scrub = TRUE ;
416 			smc->y[PB].scrub = TRUE ;
417 			GO_STATE(SC5_THRU_B) ;
418 			break ;
419 		}
420 		break ;
421 	case ACTIONS(SC4_THRU_A) :
422 		smc->mib.p[PA].fddiPORTCurrentPath = MIB_PATH_THRU ;
423 		smc->mib.p[PB].fddiPORTCurrentPath = MIB_PATH_THRU ;
424 		smc->mib.p[PA].fddiPORTMACPlacement = 0 ;
425 		smc->mib.p[PB].fddiPORTMACPlacement = INDEX_MAC ;
426 		smc->mib.fddiSMTStationStatus = MIB_SMT_STASTA_THRU ;
427 		config_mux(smc,MUX_THRUA) ;		/* configure PHY mux */
428 		smc->r.rm_loop = FALSE ;
429 		smc->r.rm_join = TRUE ;
430 		queue_event(smc,EVENT_RMT,RM_JOIN) ;/* signal RMT */
431 		ACTIONS_DONE() ;
432 		DB_CFMN(1, "CFM : %s", cfm_states[smc->mib.fddiSMTCF_State]);
433 		break ;
434 	case SC4_THRU_A :
435 		/*SC41*/
436 		if (smc->y[PB].wc_flag || !smc->y[PB].cf_join) {
437 			smc->y[PA].scrub = TRUE ;
438 			GO_STATE(SC9_C_WRAP_A) ;
439 			break ;
440 		}
441 		/*SC42*/
442 		else if (!smc->y[PA].cf_join || smc->y[PA].wc_flag) {
443 			smc->y[PB].scrub = TRUE ;
444 			GO_STATE(SC10_C_WRAP_B) ;
445 			break ;
446 		}
447 		/*SC45*/
448 		else if (smc->s.attach_s) {
449 			smc->y[PB].scrub = TRUE ;
450 			GO_STATE(SC5_THRU_B) ;
451 			break ;
452 		}
453 		break ;
454 	case ACTIONS(SC5_THRU_B) :
455 		smc->mib.p[PA].fddiPORTCurrentPath = MIB_PATH_THRU ;
456 		smc->mib.p[PB].fddiPORTCurrentPath = MIB_PATH_THRU ;
457 		smc->mib.p[PA].fddiPORTMACPlacement = INDEX_MAC ;
458 		smc->mib.p[PB].fddiPORTMACPlacement = 0 ;
459 		smc->mib.fddiSMTStationStatus = MIB_SMT_STASTA_THRU ;
460 		config_mux(smc,MUX_THRUB) ;		/* configure PHY mux */
461 		smc->r.rm_loop = FALSE ;
462 		smc->r.rm_join = TRUE ;
463 		queue_event(smc,EVENT_RMT,RM_JOIN) ;/* signal RMT */
464 		ACTIONS_DONE() ;
465 		DB_CFMN(1, "CFM : %s", cfm_states[smc->mib.fddiSMTCF_State]);
466 		break ;
467 	case SC5_THRU_B :
468 		/*SC51*/
469 		if (!smc->y[PB].cf_join || smc->y[PB].wc_flag) {
470 			smc->y[PA].scrub = TRUE ;
471 			GO_STATE(SC9_C_WRAP_A) ;
472 			break ;
473 		}
474 		/*SC52*/
475 		else if (!smc->y[PA].cf_join || smc->y[PA].wc_flag) {
476 			smc->y[PB].scrub = TRUE ;
477 			GO_STATE(SC10_C_WRAP_B) ;
478 			break ;
479 		}
480 		/*SC54*/
481 		else if (!smc->s.attach_s) {
482 			smc->y[PA].scrub = TRUE ;
483 			GO_STATE(SC4_THRU_A) ;
484 			break ;
485 		}
486 		break ;
487 	case ACTIONS(SC11_C_WRAP_S) :
488 		smc->mib.p[PS].fddiPORTCurrentPath = MIB_PATH_CONCATENATED ;
489 		smc->mib.p[PS].fddiPORTMACPlacement = INDEX_MAC ;
490 		smc->mib.fddiSMTStationStatus = MIB_SMT_STASTA_CON ;
491 		config_mux(smc,MUX_WRAPS) ;		/* configure PHY mux */
492 		if (smc->y[PA].cf_loop || smc->y[PB].cf_loop) {
493 			smc->r.rm_join = FALSE ;
494 			smc->r.rm_loop = TRUE ;
495 			queue_event(smc,EVENT_RMT,RM_LOOP) ;/* signal RMT */
496 		}
497 		if (smc->y[PA].cf_join || smc->y[PB].cf_join) {
498 			smc->r.rm_loop = FALSE ;
499 			smc->r.rm_join = TRUE ;
500 			queue_event(smc,EVENT_RMT,RM_JOIN) ;/* signal RMT */
501 		}
502 		ACTIONS_DONE() ;
503 		DB_CFMN(1, "CFM : %s", cfm_states[smc->mib.fddiSMTCF_State]);
504 		break ;
505 	case SC11_C_WRAP_S :
506 		/*SC70*/
507 		if ( !smc->y[PA].cf_join && !smc->y[PA].cf_loop &&
508 		     !smc->y[PB].cf_join && !smc->y[PB].cf_loop) {
509 			GO_STATE(SC0_ISOLATED) ;
510 			break ;
511 		}
512 		break ;
513 	default:
514 		SMT_PANIC(smc,SMT_E0106, SMT_E0106_MSG) ;
515 		break;
516 	}
517 }
518 
519 /*
520  * get MAC's input Port
521  *	return :
522  *		PA or PB
523  */
524 int cfm_get_mac_input(struct s_smc *smc)
525 {
526 	return (smc->mib.fddiSMTCF_State == SC10_C_WRAP_B ||
527 		smc->mib.fddiSMTCF_State == SC5_THRU_B) ? PB : PA;
528 }
529 
530 /*
531  * get MAC's output Port
532  *	return :
533  *		PA or PB
534  */
535 int cfm_get_mac_output(struct s_smc *smc)
536 {
537 	return (smc->mib.fddiSMTCF_State == SC10_C_WRAP_B ||
538 		smc->mib.fddiSMTCF_State == SC4_THRU_A) ? PB : PA;
539 }
540 
541 static char path_iso[] = {
542 	0,0,	0,RES_PORT,	0,PA + INDEX_PORT,	0,PATH_ISO,
543 	0,0,	0,RES_MAC,	0,INDEX_MAC,		0,PATH_ISO,
544 	0,0,	0,RES_PORT,	0,PB + INDEX_PORT,	0,PATH_ISO
545 } ;
546 
547 static char path_wrap_a[] = {
548 	0,0,	0,RES_PORT,	0,PA + INDEX_PORT,	0,PATH_PRIM,
549 	0,0,	0,RES_MAC,	0,INDEX_MAC,		0,PATH_PRIM,
550 	0,0,	0,RES_PORT,	0,PB + INDEX_PORT,	0,PATH_ISO
551 } ;
552 
553 static char path_wrap_b[] = {
554 	0,0,	0,RES_PORT,	0,PB + INDEX_PORT,	0,PATH_PRIM,
555 	0,0,	0,RES_MAC,	0,INDEX_MAC,		0,PATH_PRIM,
556 	0,0,	0,RES_PORT,	0,PA + INDEX_PORT,	0,PATH_ISO
557 } ;
558 
559 static char path_thru[] = {
560 	0,0,	0,RES_PORT,	0,PA + INDEX_PORT,	0,PATH_PRIM,
561 	0,0,	0,RES_MAC,	0,INDEX_MAC,		0,PATH_PRIM,
562 	0,0,	0,RES_PORT,	0,PB + INDEX_PORT,	0,PATH_PRIM
563 } ;
564 
565 static char path_wrap_s[] = {
566 	0,0,	0,RES_PORT,	0,PS + INDEX_PORT,	0,PATH_PRIM,
567 	0,0,	0,RES_MAC,	0,INDEX_MAC,		0,PATH_PRIM,
568 } ;
569 
570 static char path_iso_s[] = {
571 	0,0,	0,RES_PORT,	0,PS + INDEX_PORT,	0,PATH_ISO,
572 	0,0,	0,RES_MAC,	0,INDEX_MAC,		0,PATH_ISO,
573 } ;
574 
575 int cem_build_path(struct s_smc *smc, char *to, int path_index)
576 {
577 	char	*path ;
578 	int	len ;
579 
580 	switch (smc->mib.fddiSMTCF_State) {
581 	default :
582 	case SC0_ISOLATED :
583 		path = smc->s.sas ? path_iso_s : path_iso ;
584 		len = smc->s.sas ? sizeof(path_iso_s) :  sizeof(path_iso) ;
585 		break ;
586 	case SC9_C_WRAP_A :
587 		path = path_wrap_a ;
588 		len = sizeof(path_wrap_a) ;
589 		break ;
590 	case SC10_C_WRAP_B :
591 		path = path_wrap_b ;
592 		len = sizeof(path_wrap_b) ;
593 		break ;
594 	case SC4_THRU_A :
595 		path = path_thru ;
596 		len = sizeof(path_thru) ;
597 		break ;
598 	case SC11_C_WRAP_S :
599 		path = path_wrap_s ;
600 		len = sizeof(path_wrap_s) ;
601 		break ;
602 	}
603 	memcpy(to,path,len) ;
604 
605 	LINT_USE(path_index);
606 
607 	return len;
608 }
609