xref: /openbmc/linux/drivers/net/fddi/skfp/ecm.c (revision b830f94f)
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 ECM
15 	Entity Coordination Management
16 	Hardware independent state machine
17 */
18 
19 /*
20  * Hardware independent state machine implemantation
21  * The following external SMT functions are referenced :
22  *
23  * 		queue_event()
24  * 		smt_timer_start()
25  * 		smt_timer_stop()
26  *
27  * 	The following external HW dependent functions are referenced :
28  * 		sm_pm_bypass_req()
29  * 		sm_pm_get_ls()
30  *
31  * 	The following HW dependent events are required :
32  *		NONE
33  *
34  */
35 
36 #include "h/types.h"
37 #include "h/fddi.h"
38 #include "h/smc.h"
39 
40 #define KERNEL
41 #include "h/smtstate.h"
42 
43 #ifndef	lint
44 static const char ID_sccs[] = "@(#)ecm.c	2.7 99/08/05 (C) SK " ;
45 #endif
46 
47 /*
48  * FSM Macros
49  */
50 #define AFLAG	0x10
51 #define GO_STATE(x)	(smc->mib.fddiSMTECMState = (x)|AFLAG)
52 #define ACTIONS_DONE()	(smc->mib.fddiSMTECMState &= ~AFLAG)
53 #define ACTIONS(x)	(x|AFLAG)
54 
55 #define EC0_OUT		0			/* not inserted */
56 #define EC1_IN		1			/* inserted */
57 #define EC2_TRACE	2			/* tracing */
58 #define EC3_LEAVE	3			/* leaving the ring */
59 #define EC4_PATH_TEST	4			/* performing path test */
60 #define EC5_INSERT	5			/* bypass being turned on */
61 #define EC6_CHECK	6			/* checking bypass */
62 #define EC7_DEINSERT	7			/* bypass being turnde off */
63 
64 /*
65  * symbolic state names
66  */
67 static const char * const ecm_states[] = {
68 	"EC0_OUT","EC1_IN","EC2_TRACE","EC3_LEAVE","EC4_PATH_TEST",
69 	"EC5_INSERT","EC6_CHECK","EC7_DEINSERT"
70 } ;
71 
72 /*
73  * symbolic event names
74  */
75 static const char * const ecm_events[] = {
76 	"NONE","EC_CONNECT","EC_DISCONNECT","EC_TRACE_PROP","EC_PATH_TEST",
77 	"EC_TIMEOUT_TD","EC_TIMEOUT_TMAX",
78 	"EC_TIMEOUT_IMAX","EC_TIMEOUT_INMAX","EC_TEST_DONE"
79 } ;
80 
81 /*
82  * all Globals  are defined in smc.h
83  * struct s_ecm
84  */
85 
86 /*
87  * function declarations
88  */
89 
90 static void ecm_fsm(struct s_smc *smc, int cmd);
91 static void start_ecm_timer(struct s_smc *smc, u_long value, int event);
92 static void stop_ecm_timer(struct s_smc *smc);
93 static void prop_actions(struct s_smc *smc);
94 
95 /*
96 	init ECM state machine
97 	clear all ECM vars and flags
98 */
99 void ecm_init(struct s_smc *smc)
100 {
101 	smc->e.path_test = PT_PASSED ;
102 	smc->e.trace_prop = 0 ;
103 	smc->e.sb_flag = 0 ;
104 	smc->mib.fddiSMTECMState = ACTIONS(EC0_OUT) ;
105 	smc->e.ecm_line_state = FALSE ;
106 }
107 
108 /*
109 	ECM state machine
110 	called by dispatcher
111 
112 	do
113 		display state change
114 		process event
115 	until SM is stable
116 */
117 void ecm(struct s_smc *smc, int event)
118 {
119 	int	state ;
120 
121 	do {
122 		DB_ECM("ECM : state %s%s event %s",
123 		       smc->mib.fddiSMTECMState & AFLAG ? "ACTIONS " : "",
124 		       ecm_states[smc->mib.fddiSMTECMState & ~AFLAG],
125 		       ecm_events[event]);
126 		state = smc->mib.fddiSMTECMState ;
127 		ecm_fsm(smc,event) ;
128 		event = 0 ;
129 	} while (state != smc->mib.fddiSMTECMState) ;
130 	ecm_state_change(smc,(int)smc->mib.fddiSMTECMState) ;
131 }
132 
133 /*
134 	process ECM event
135 */
136 static void ecm_fsm(struct s_smc *smc, int cmd)
137 {
138 	int ls_a ;			/* current line state PHY A */
139 	int ls_b ;			/* current line state PHY B */
140 	int	p ;			/* ports */
141 
142 
143 	smc->mib.fddiSMTBypassPresent = sm_pm_bypass_present(smc) ;
144 	if (cmd == EC_CONNECT)
145 		smc->mib.fddiSMTRemoteDisconnectFlag = FALSE ;
146 
147 	/* For AIX event notification: */
148 	/* Is a disconnect  command remotely issued ? */
149 	if (cmd == EC_DISCONNECT &&
150 		smc->mib.fddiSMTRemoteDisconnectFlag == TRUE)
151 		AIX_EVENT (smc, (u_long) CIO_HARD_FAIL, (u_long)
152 			FDDI_REMOTE_DISCONNECT, smt_get_event_word(smc),
153 			smt_get_error_word(smc) );
154 
155 	/*jd 05-Aug-1999 Bug #10419 "Port Disconnect fails at Dup MAc Cond."*/
156 	if (cmd == EC_CONNECT) {
157 		smc->e.DisconnectFlag = FALSE ;
158 	}
159 	else if (cmd == EC_DISCONNECT) {
160 		smc->e.DisconnectFlag = TRUE ;
161 	}
162 
163 	switch(smc->mib.fddiSMTECMState) {
164 	case ACTIONS(EC0_OUT) :
165 		/*
166 		 * We do not perform a path test
167 		 */
168 		smc->e.path_test = PT_PASSED ;
169 		smc->e.ecm_line_state = FALSE ;
170 		stop_ecm_timer(smc) ;
171 		ACTIONS_DONE() ;
172 		break ;
173 	case EC0_OUT:
174 		/*EC01*/
175 		if (cmd == EC_CONNECT && !smc->mib.fddiSMTBypassPresent
176 			&& smc->e.path_test==PT_PASSED) {
177 			GO_STATE(EC1_IN) ;
178 			break ;
179 		}
180 		/*EC05*/
181 		else if (cmd == EC_CONNECT && (smc->e.path_test==PT_PASSED) &&
182 			smc->mib.fddiSMTBypassPresent &&
183 			(smc->s.sas == SMT_DAS)) {
184 			GO_STATE(EC5_INSERT) ;
185 			break ;
186 		}
187 		break;
188 	case ACTIONS(EC1_IN) :
189 		stop_ecm_timer(smc) ;
190 		smc->e.trace_prop = 0 ;
191 		sm_ma_control(smc,MA_TREQ) ;
192 		for (p = 0 ; p < NUMPHYS ; p++)
193 			if (smc->mib.p[p].fddiPORTHardwarePresent)
194 				queue_event(smc,EVENT_PCMA+p,PC_START) ;
195 		ACTIONS_DONE() ;
196 		break ;
197 	case EC1_IN:
198 		/*EC12*/
199 		if (cmd == EC_TRACE_PROP) {
200 			prop_actions(smc) ;
201 			GO_STATE(EC2_TRACE) ;
202 			break ;
203 		}
204 		/*EC13*/
205 		else if (cmd == EC_DISCONNECT) {
206 			GO_STATE(EC3_LEAVE) ;
207 			break ;
208 		}
209 		break;
210 	case ACTIONS(EC2_TRACE) :
211 		start_ecm_timer(smc,MIB2US(smc->mib.fddiSMTTrace_MaxExpiration),
212 			EC_TIMEOUT_TMAX) ;
213 		ACTIONS_DONE() ;
214 		break ;
215 	case EC2_TRACE :
216 		/*EC22*/
217 		if (cmd == EC_TRACE_PROP) {
218 			prop_actions(smc) ;
219 			GO_STATE(EC2_TRACE) ;
220 			break ;
221 		}
222 		/*EC23a*/
223 		else if (cmd == EC_DISCONNECT) {
224 			smc->e.path_test = PT_EXITING ;
225 			GO_STATE(EC3_LEAVE) ;
226 			break ;
227 		}
228 		/*EC23b*/
229 		else if (smc->e.path_test == PT_PENDING) {
230 			GO_STATE(EC3_LEAVE) ;
231 			break ;
232 		}
233 		/*EC23c*/
234 		else if (cmd == EC_TIMEOUT_TMAX) {
235 			/* Trace_Max is expired */
236 			/* -> send AIX_EVENT */
237 			AIX_EVENT(smc, (u_long) FDDI_RING_STATUS,
238 				(u_long) FDDI_SMT_ERROR, (u_long)
239 				FDDI_TRACE_MAX, smt_get_error_word(smc));
240 			smc->e.path_test = PT_PENDING ;
241 			GO_STATE(EC3_LEAVE) ;
242 			break ;
243 		}
244 		break ;
245 	case ACTIONS(EC3_LEAVE) :
246 		start_ecm_timer(smc,smc->s.ecm_td_min,EC_TIMEOUT_TD) ;
247 		for (p = 0 ; p < NUMPHYS ; p++)
248 			queue_event(smc,EVENT_PCMA+p,PC_STOP) ;
249 		ACTIONS_DONE() ;
250 		break ;
251 	case EC3_LEAVE:
252 		/*EC30*/
253 		if (cmd == EC_TIMEOUT_TD && !smc->mib.fddiSMTBypassPresent &&
254 			(smc->e.path_test != PT_PENDING)) {
255 			GO_STATE(EC0_OUT) ;
256 			break ;
257 		}
258 		/*EC34*/
259 		else if (cmd == EC_TIMEOUT_TD &&
260 			(smc->e.path_test == PT_PENDING)) {
261 			GO_STATE(EC4_PATH_TEST) ;
262 			break ;
263 		}
264 		/*EC31*/
265 		else if (cmd == EC_CONNECT && smc->e.path_test == PT_PASSED) {
266 			GO_STATE(EC1_IN) ;
267 			break ;
268 		}
269 		/*EC33*/
270 		else if (cmd == EC_DISCONNECT &&
271 			smc->e.path_test == PT_PENDING) {
272 			smc->e.path_test = PT_EXITING ;
273 			/*
274 			 * stay in state - state will be left via timeout
275 			 */
276 		}
277 		/*EC37*/
278 		else if (cmd == EC_TIMEOUT_TD &&
279 			smc->mib.fddiSMTBypassPresent &&
280 			smc->e.path_test != PT_PENDING) {
281 			GO_STATE(EC7_DEINSERT) ;
282 			break ;
283 		}
284 		break ;
285 	case ACTIONS(EC4_PATH_TEST) :
286 		stop_ecm_timer(smc) ;
287 		smc->e.path_test = PT_TESTING ;
288 		start_ecm_timer(smc,smc->s.ecm_test_done,EC_TEST_DONE) ;
289 		/* now perform path test ... just a simulation */
290 		ACTIONS_DONE() ;
291 		break ;
292 	case EC4_PATH_TEST :
293 		/* path test done delay */
294 		if (cmd == EC_TEST_DONE)
295 			smc->e.path_test = PT_PASSED ;
296 
297 		if (smc->e.path_test == PT_FAILED)
298 			RS_SET(smc,RS_PATHTEST) ;
299 
300 		/*EC40a*/
301 		if (smc->e.path_test == PT_FAILED &&
302 			!smc->mib.fddiSMTBypassPresent) {
303 			GO_STATE(EC0_OUT) ;
304 			break ;
305 		}
306 		/*EC40b*/
307 		else if (cmd == EC_DISCONNECT &&
308 			!smc->mib.fddiSMTBypassPresent) {
309 			GO_STATE(EC0_OUT) ;
310 			break ;
311 		}
312 		/*EC41*/
313 		else if (smc->e.path_test == PT_PASSED) {
314 			GO_STATE(EC1_IN) ;
315 			break ;
316 		}
317 		/*EC47a*/
318 		else if (smc->e.path_test == PT_FAILED &&
319 			smc->mib.fddiSMTBypassPresent) {
320 			GO_STATE(EC7_DEINSERT) ;
321 			break ;
322 		}
323 		/*EC47b*/
324 		else if (cmd == EC_DISCONNECT &&
325 			smc->mib.fddiSMTBypassPresent) {
326 			GO_STATE(EC7_DEINSERT) ;
327 			break ;
328 		}
329 		break ;
330 	case ACTIONS(EC5_INSERT) :
331 		sm_pm_bypass_req(smc,BP_INSERT);
332 		start_ecm_timer(smc,smc->s.ecm_in_max,EC_TIMEOUT_INMAX) ;
333 		ACTIONS_DONE() ;
334 		break ;
335 	case EC5_INSERT :
336 		/*EC56*/
337 		if (cmd == EC_TIMEOUT_INMAX) {
338 			GO_STATE(EC6_CHECK) ;
339 			break ;
340 		}
341 		/*EC57*/
342 		else if (cmd == EC_DISCONNECT) {
343 			GO_STATE(EC7_DEINSERT) ;
344 			break ;
345 		}
346 		break ;
347 	case ACTIONS(EC6_CHECK) :
348 		/*
349 		 * in EC6_CHECK, we *POLL* the line state !
350 		 * check whether both bypass switches have switched.
351 		 */
352 		start_ecm_timer(smc,smc->s.ecm_check_poll,0) ;
353 		smc->e.ecm_line_state = TRUE ;	/* flag to pcm: report Q/HLS */
354 		ACTIONS_DONE() ;
355 		break ;
356 	case EC6_CHECK :
357 		ls_a = sm_pm_get_ls(smc,PA) ;
358 		ls_b = sm_pm_get_ls(smc,PB) ;
359 
360 		/*EC61*/
361 		if (((ls_a == PC_QLS) || (ls_a == PC_HLS)) &&
362 		    ((ls_b == PC_QLS) || (ls_b == PC_HLS)) ) {
363 			smc->e.sb_flag = FALSE ;
364 			smc->e.ecm_line_state = FALSE ;
365 			GO_STATE(EC1_IN) ;
366 			break ;
367 		}
368 		/*EC66*/
369 		else if (!smc->e.sb_flag &&
370 			 (((ls_a == PC_ILS) && (ls_b == PC_QLS)) ||
371 			  ((ls_a == PC_QLS) && (ls_b == PC_ILS)))){
372 			smc->e.sb_flag = TRUE ;
373 			DB_ECMN(1, "ECM : EC6_CHECK - stuck bypass");
374 			AIX_EVENT(smc, (u_long) FDDI_RING_STATUS, (u_long)
375 				FDDI_SMT_ERROR, (u_long) FDDI_BYPASS_STUCK,
376 				smt_get_error_word(smc));
377 		}
378 		/*EC67*/
379 		else if (cmd == EC_DISCONNECT) {
380 			smc->e.ecm_line_state = FALSE ;
381 			GO_STATE(EC7_DEINSERT) ;
382 			break ;
383 		}
384 		else {
385 			/*
386 			 * restart poll
387 			 */
388 			start_ecm_timer(smc,smc->s.ecm_check_poll,0) ;
389 		}
390 		break ;
391 	case ACTIONS(EC7_DEINSERT) :
392 		sm_pm_bypass_req(smc,BP_DEINSERT);
393 		start_ecm_timer(smc,smc->s.ecm_i_max,EC_TIMEOUT_IMAX) ;
394 		ACTIONS_DONE() ;
395 		break ;
396 	case EC7_DEINSERT:
397 		/*EC70*/
398 		if (cmd == EC_TIMEOUT_IMAX) {
399 			GO_STATE(EC0_OUT) ;
400 			break ;
401 		}
402 		/*EC75*/
403 		else if (cmd == EC_CONNECT && smc->e.path_test == PT_PASSED) {
404 			GO_STATE(EC5_INSERT) ;
405 			break ;
406 		}
407 		break;
408 	default:
409 		SMT_PANIC(smc,SMT_E0107, SMT_E0107_MSG) ;
410 		break;
411 	}
412 }
413 
414 #ifndef	CONCENTRATOR
415 /*
416  * trace propagation actions for SAS & DAS
417  */
418 static void prop_actions(struct s_smc *smc)
419 {
420 	int	port_in = 0 ;
421 	int	port_out = 0 ;
422 
423 	RS_SET(smc,RS_EVENT) ;
424 	switch (smc->s.sas) {
425 	case SMT_SAS :
426 		port_in = port_out = pcm_get_s_port(smc) ;
427 		break ;
428 	case SMT_DAS :
429 		port_in = cfm_get_mac_input(smc) ;	/* PA or PB */
430 		port_out = cfm_get_mac_output(smc) ;	/* PA or PB */
431 		break ;
432 	case SMT_NAC :
433 		SMT_PANIC(smc,SMT_E0108, SMT_E0108_MSG) ;
434 		return ;
435 	}
436 
437 	DB_ECM("ECM : prop_actions - trace_prop %lu", smc->e.trace_prop);
438 	DB_ECM("ECM : prop_actions - in %d out %d", port_in, port_out);
439 
440 	if (smc->e.trace_prop & ENTITY_BIT(ENTITY_MAC)) {
441 		/* trace initiatior */
442 		DB_ECM("ECM : initiate TRACE on PHY %c", 'A' + port_in - PA);
443 		queue_event(smc,EVENT_PCM+port_in,PC_TRACE) ;
444 	}
445 	else if ((smc->e.trace_prop & ENTITY_BIT(ENTITY_PHY(PA))) &&
446 		port_out != PA) {
447 		/* trace propagate upstream */
448 		DB_ECM("ECM : propagate TRACE on PHY B");
449 		queue_event(smc,EVENT_PCMB,PC_TRACE) ;
450 	}
451 	else if ((smc->e.trace_prop & ENTITY_BIT(ENTITY_PHY(PB))) &&
452 		port_out != PB) {
453 		/* trace propagate upstream */
454 		DB_ECM("ECM : propagate TRACE on PHY A");
455 		queue_event(smc,EVENT_PCMA,PC_TRACE) ;
456 	}
457 	else {
458 		/* signal trace termination */
459 		DB_ECM("ECM : TRACE terminated");
460 		smc->e.path_test = PT_PENDING ;
461 	}
462 	smc->e.trace_prop = 0 ;
463 }
464 #else
465 /*
466  * trace propagation actions for Concentrator
467  */
468 static void prop_actions(struct s_smc *smc)
469 {
470 	int	initiator ;
471 	int	upstream ;
472 	int	p ;
473 
474 	RS_SET(smc,RS_EVENT) ;
475 	while (smc->e.trace_prop) {
476 		DB_ECM("ECM : prop_actions - trace_prop %d",
477 		       smc->e.trace_prop);
478 
479 		if (smc->e.trace_prop & ENTITY_BIT(ENTITY_MAC)) {
480 			initiator = ENTITY_MAC ;
481 			smc->e.trace_prop &= ~ENTITY_BIT(ENTITY_MAC) ;
482 			DB_ECM("ECM: MAC initiates trace");
483 		}
484 		else {
485 			for (p = NUMPHYS-1 ; p >= 0 ; p--) {
486 				if (smc->e.trace_prop &
487 					ENTITY_BIT(ENTITY_PHY(p)))
488 					break ;
489 			}
490 			initiator = ENTITY_PHY(p) ;
491 			smc->e.trace_prop &= ~ENTITY_BIT(ENTITY_PHY(p)) ;
492 		}
493 		upstream = cem_get_upstream(smc,initiator) ;
494 
495 		if (upstream == ENTITY_MAC) {
496 			/* signal trace termination */
497 			DB_ECM("ECM : TRACE terminated");
498 			smc->e.path_test = PT_PENDING ;
499 		}
500 		else {
501 			/* trace propagate upstream */
502 			DB_ECM("ECM : propagate TRACE on PHY %d", upstream);
503 			queue_event(smc,EVENT_PCM+upstream,PC_TRACE) ;
504 		}
505 	}
506 }
507 #endif
508 
509 
510 /*
511  * SMT timer interface
512  *	start ECM timer
513  */
514 static void start_ecm_timer(struct s_smc *smc, u_long value, int event)
515 {
516 	smt_timer_start(smc,&smc->e.ecm_timer,value,EV_TOKEN(EVENT_ECM,event));
517 }
518 
519 /*
520  * SMT timer interface
521  *	stop ECM timer
522  */
523 static void stop_ecm_timer(struct s_smc *smc)
524 {
525 	if (smc->e.ecm_timer.tm_active)
526 		smt_timer_stop(smc,&smc->e.ecm_timer) ;
527 }
528