Linux 2.6.17.7
[linux/fpc-iii.git] / drivers / net / skfp / rmt.c
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1 /******************************************************************************
3 * (C)Copyright 1998,1999 SysKonnect,
4 * a business unit of Schneider & Koch & Co. Datensysteme GmbH.
6 * See the file "skfddi.c" for further information.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * The information in this file is provided "AS IS" without warranty.
15 ******************************************************************************/
18 SMT RMT
19 Ring Management
23 * Hardware independent state machine implemantation
24 * The following external SMT functions are referenced :
26 * queue_event()
27 * smt_timer_start()
28 * smt_timer_stop()
30 * The following external HW dependent functions are referenced :
31 * sm_ma_control()
32 * sm_mac_check_beacon_claim()
34 * The following HW dependent events are required :
35 * RM_RING_OP
36 * RM_RING_NON_OP
37 * RM_MY_BEACON
38 * RM_OTHER_BEACON
39 * RM_MY_CLAIM
40 * RM_TRT_EXP
41 * RM_VALID_CLAIM
45 #include "h/types.h"
46 #include "h/fddi.h"
47 #include "h/smc.h"
49 #define KERNEL
50 #include "h/smtstate.h"
52 #ifndef lint
53 static const char ID_sccs[] = "@(#)rmt.c 2.13 99/07/02 (C) SK " ;
54 #endif
57 * FSM Macros
59 #define AFLAG 0x10
60 #define GO_STATE(x) (smc->mib.m[MAC0].fddiMACRMTState = (x)|AFLAG)
61 #define ACTIONS_DONE() (smc->mib.m[MAC0].fddiMACRMTState &= ~AFLAG)
62 #define ACTIONS(x) (x|AFLAG)
64 #define RM0_ISOLATED 0
65 #define RM1_NON_OP 1 /* not operational */
66 #define RM2_RING_OP 2 /* ring operational */
67 #define RM3_DETECT 3 /* detect dupl addresses */
68 #define RM4_NON_OP_DUP 4 /* dupl. addr detected */
69 #define RM5_RING_OP_DUP 5 /* ring oper. with dupl. addr */
70 #define RM6_DIRECTED 6 /* sending directed beacons */
71 #define RM7_TRACE 7 /* trace initiated */
73 #ifdef DEBUG
75 * symbolic state names
77 static const char * const rmt_states[] = {
78 "RM0_ISOLATED","RM1_NON_OP","RM2_RING_OP","RM3_DETECT",
79 "RM4_NON_OP_DUP","RM5_RING_OP_DUP","RM6_DIRECTED",
80 "RM7_TRACE"
81 } ;
84 * symbolic event names
86 static const char * const rmt_events[] = {
87 "NONE","RM_RING_OP","RM_RING_NON_OP","RM_MY_BEACON",
88 "RM_OTHER_BEACON","RM_MY_CLAIM","RM_TRT_EXP","RM_VALID_CLAIM",
89 "RM_JOIN","RM_LOOP","RM_DUP_ADDR","RM_ENABLE_FLAG",
90 "RM_TIMEOUT_NON_OP","RM_TIMEOUT_T_STUCK",
91 "RM_TIMEOUT_ANNOUNCE","RM_TIMEOUT_T_DIRECT",
92 "RM_TIMEOUT_D_MAX","RM_TIMEOUT_POLL","RM_TX_STATE_CHANGE"
93 } ;
94 #endif
97 * Globals
98 * in struct s_rmt
103 * function declarations
105 static void rmt_fsm(struct s_smc *smc, int cmd);
106 static void start_rmt_timer0(struct s_smc *smc, u_long value, int event);
107 static void start_rmt_timer1(struct s_smc *smc, u_long value, int event);
108 static void start_rmt_timer2(struct s_smc *smc, u_long value, int event);
109 static void stop_rmt_timer0(struct s_smc *smc);
110 static void stop_rmt_timer1(struct s_smc *smc);
111 static void stop_rmt_timer2(struct s_smc *smc);
112 static void rmt_dup_actions(struct s_smc *smc);
113 static void rmt_reinsert_actions(struct s_smc *smc);
114 static void rmt_leave_actions(struct s_smc *smc);
115 static void rmt_new_dup_actions(struct s_smc *smc);
117 #ifndef SUPERNET_3
118 extern void restart_trt_for_dbcn() ;
119 #endif /*SUPERNET_3*/
122 init RMT state machine
123 clear all RMT vars and flags
125 void rmt_init(struct s_smc *smc)
127 smc->mib.m[MAC0].fddiMACRMTState = ACTIONS(RM0_ISOLATED) ;
128 smc->r.dup_addr_test = DA_NONE ;
129 smc->r.da_flag = 0 ;
130 smc->mib.m[MAC0].fddiMACMA_UnitdataAvailable = FALSE ;
131 smc->r.sm_ma_avail = FALSE ;
132 smc->r.loop_avail = 0 ;
133 smc->r.bn_flag = 0 ;
134 smc->r.jm_flag = 0 ;
135 smc->r.no_flag = TRUE ;
139 RMT state machine
140 called by dispatcher
143 display state change
144 process event
145 until SM is stable
147 void rmt(struct s_smc *smc, int event)
149 int state ;
151 do {
152 DB_RMT("RMT : state %s%s",
153 (smc->mib.m[MAC0].fddiMACRMTState & AFLAG) ? "ACTIONS " : "",
154 rmt_states[smc->mib.m[MAC0].fddiMACRMTState & ~AFLAG]) ;
155 DB_RMT(" event %s\n",rmt_events[event],0) ;
156 state = smc->mib.m[MAC0].fddiMACRMTState ;
157 rmt_fsm(smc,event) ;
158 event = 0 ;
159 } while (state != smc->mib.m[MAC0].fddiMACRMTState) ;
160 rmt_state_change(smc,(int)smc->mib.m[MAC0].fddiMACRMTState) ;
164 process RMT event
166 static void rmt_fsm(struct s_smc *smc, int cmd)
169 * RM00-RM70 : from all states
171 if (!smc->r.rm_join && !smc->r.rm_loop &&
172 smc->mib.m[MAC0].fddiMACRMTState != ACTIONS(RM0_ISOLATED) &&
173 smc->mib.m[MAC0].fddiMACRMTState != RM0_ISOLATED) {
174 RS_SET(smc,RS_NORINGOP) ;
175 rmt_indication(smc,0) ;
176 GO_STATE(RM0_ISOLATED) ;
177 return ;
180 switch(smc->mib.m[MAC0].fddiMACRMTState) {
181 case ACTIONS(RM0_ISOLATED) :
182 stop_rmt_timer0(smc) ;
183 stop_rmt_timer1(smc) ;
184 stop_rmt_timer2(smc) ;
187 * Disable MAC.
189 sm_ma_control(smc,MA_OFFLINE) ;
190 smc->mib.m[MAC0].fddiMACMA_UnitdataAvailable = FALSE ;
191 smc->r.loop_avail = FALSE ;
192 smc->r.sm_ma_avail = FALSE ;
193 smc->r.no_flag = TRUE ;
194 DB_RMTN(1,"RMT : ISOLATED\n",0,0) ;
195 ACTIONS_DONE() ;
196 break ;
197 case RM0_ISOLATED :
198 /*RM01*/
199 if (smc->r.rm_join || smc->r.rm_loop) {
201 * According to the standard the MAC must be reset
202 * here. The FORMAC will be initialized and Claim
203 * and Beacon Frames will be uploaded to the MAC.
204 * So any change of Treq will take effect NOW.
206 sm_ma_control(smc,MA_RESET) ;
207 GO_STATE(RM1_NON_OP) ;
208 break ;
210 break ;
211 case ACTIONS(RM1_NON_OP) :
212 start_rmt_timer0(smc,smc->s.rmt_t_non_op,RM_TIMEOUT_NON_OP) ;
213 stop_rmt_timer1(smc) ;
214 stop_rmt_timer2(smc) ;
215 sm_ma_control(smc,MA_BEACON) ;
216 DB_RMTN(1,"RMT : RING DOWN\n",0,0) ;
217 RS_SET(smc,RS_NORINGOP) ;
218 smc->r.sm_ma_avail = FALSE ;
219 rmt_indication(smc,0) ;
220 ACTIONS_DONE() ;
221 break ;
222 case RM1_NON_OP :
223 /*RM12*/
224 if (cmd == RM_RING_OP) {
225 RS_SET(smc,RS_RINGOPCHANGE) ;
226 GO_STATE(RM2_RING_OP) ;
227 break ;
229 /*RM13*/
230 else if (cmd == RM_TIMEOUT_NON_OP) {
231 smc->r.bn_flag = FALSE ;
232 smc->r.no_flag = TRUE ;
233 GO_STATE(RM3_DETECT) ;
234 break ;
236 break ;
237 case ACTIONS(RM2_RING_OP) :
238 stop_rmt_timer0(smc) ;
239 stop_rmt_timer1(smc) ;
240 stop_rmt_timer2(smc) ;
241 smc->r.no_flag = FALSE ;
242 if (smc->r.rm_loop)
243 smc->r.loop_avail = TRUE ;
244 if (smc->r.rm_join) {
245 smc->r.sm_ma_avail = TRUE ;
246 if (smc->mib.m[MAC0].fddiMACMA_UnitdataEnable)
247 smc->mib.m[MAC0].fddiMACMA_UnitdataAvailable = TRUE ;
248 else
249 smc->mib.m[MAC0].fddiMACMA_UnitdataAvailable = FALSE ;
251 DB_RMTN(1,"RMT : RING UP\n",0,0) ;
252 RS_CLEAR(smc,RS_NORINGOP) ;
253 RS_SET(smc,RS_RINGOPCHANGE) ;
254 rmt_indication(smc,1) ;
255 smt_stat_counter(smc,0) ;
256 ACTIONS_DONE() ;
257 break ;
258 case RM2_RING_OP :
259 /*RM21*/
260 if (cmd == RM_RING_NON_OP) {
261 smc->mib.m[MAC0].fddiMACMA_UnitdataAvailable = FALSE ;
262 smc->r.loop_avail = FALSE ;
263 RS_SET(smc,RS_RINGOPCHANGE) ;
264 GO_STATE(RM1_NON_OP) ;
265 break ;
267 /*RM22a*/
268 else if (cmd == RM_ENABLE_FLAG) {
269 if (smc->mib.m[MAC0].fddiMACMA_UnitdataEnable)
270 smc->mib.m[MAC0].fddiMACMA_UnitdataAvailable = TRUE ;
271 else
272 smc->mib.m[MAC0].fddiMACMA_UnitdataAvailable = FALSE ;
274 /*RM25*/
275 else if (smc->r.dup_addr_test == DA_FAILED) {
276 smc->mib.m[MAC0].fddiMACMA_UnitdataAvailable = FALSE ;
277 smc->r.loop_avail = FALSE ;
278 smc->r.da_flag = TRUE ;
279 GO_STATE(RM5_RING_OP_DUP) ;
280 break ;
282 break ;
283 case ACTIONS(RM3_DETECT) :
284 start_rmt_timer0(smc,smc->s.mac_d_max*2,RM_TIMEOUT_D_MAX) ;
285 start_rmt_timer1(smc,smc->s.rmt_t_stuck,RM_TIMEOUT_T_STUCK) ;
286 start_rmt_timer2(smc,smc->s.rmt_t_poll,RM_TIMEOUT_POLL) ;
287 sm_mac_check_beacon_claim(smc) ;
288 DB_RMTN(1,"RMT : RM3_DETECT\n",0,0) ;
289 ACTIONS_DONE() ;
290 break ;
291 case RM3_DETECT :
292 if (cmd == RM_TIMEOUT_POLL) {
293 start_rmt_timer2(smc,smc->s.rmt_t_poll,RM_TIMEOUT_POLL);
294 sm_mac_check_beacon_claim(smc) ;
295 break ;
297 if (cmd == RM_TIMEOUT_D_MAX) {
298 smc->r.timer0_exp = TRUE ;
301 *jd(22-Feb-1999)
302 * We need a time ">= 2*mac_d_max" since we had finished
303 * Claim or Beacon state. So we will restart timer0 at
304 * every state change.
306 if (cmd == RM_TX_STATE_CHANGE) {
307 start_rmt_timer0(smc,
308 smc->s.mac_d_max*2,
309 RM_TIMEOUT_D_MAX) ;
311 /*RM32*/
312 if (cmd == RM_RING_OP) {
313 GO_STATE(RM2_RING_OP) ;
314 break ;
316 /*RM33a*/
317 else if ((cmd == RM_MY_BEACON || cmd == RM_OTHER_BEACON)
318 && smc->r.bn_flag) {
319 smc->r.bn_flag = FALSE ;
321 /*RM33b*/
322 else if (cmd == RM_TRT_EXP && !smc->r.bn_flag) {
323 int tx ;
325 * set bn_flag only if in state T4 or T5:
326 * only if we're the beaconer should we start the
327 * trace !
329 if ((tx = sm_mac_get_tx_state(smc)) == 4 || tx == 5) {
330 DB_RMTN(2,"RMT : DETECT && TRT_EXPIRED && T4/T5\n",0,0);
331 smc->r.bn_flag = TRUE ;
333 * If one of the upstream stations beaconed
334 * and the link to the upstream neighbor is
335 * lost we need to restart the stuck timer to
336 * check the "stuck beacon" condition.
338 start_rmt_timer1(smc,smc->s.rmt_t_stuck,
339 RM_TIMEOUT_T_STUCK) ;
342 * We do NOT need to clear smc->r.bn_flag in case of
343 * not being in state T4 or T5, because the flag
344 * must be cleared in order to get in this condition.
347 DB_RMTN(2,
348 "RMT : sm_mac_get_tx_state() = %d (bn_flag = %d)\n",
349 tx,smc->r.bn_flag) ;
351 /*RM34a*/
352 else if (cmd == RM_MY_CLAIM && smc->r.timer0_exp) {
353 rmt_new_dup_actions(smc) ;
354 GO_STATE(RM4_NON_OP_DUP) ;
355 break ;
357 /*RM34b*/
358 else if (cmd == RM_MY_BEACON && smc->r.timer0_exp) {
359 rmt_new_dup_actions(smc) ;
360 GO_STATE(RM4_NON_OP_DUP) ;
361 break ;
363 /*RM34c*/
364 else if (cmd == RM_VALID_CLAIM) {
365 rmt_new_dup_actions(smc) ;
366 GO_STATE(RM4_NON_OP_DUP) ;
367 break ;
369 /*RM36*/
370 else if (cmd == RM_TIMEOUT_T_STUCK &&
371 smc->r.rm_join && smc->r.bn_flag) {
372 GO_STATE(RM6_DIRECTED) ;
373 break ;
375 break ;
376 case ACTIONS(RM4_NON_OP_DUP) :
377 start_rmt_timer0(smc,smc->s.rmt_t_announce,RM_TIMEOUT_ANNOUNCE);
378 start_rmt_timer1(smc,smc->s.rmt_t_stuck,RM_TIMEOUT_T_STUCK) ;
379 start_rmt_timer2(smc,smc->s.rmt_t_poll,RM_TIMEOUT_POLL) ;
380 sm_mac_check_beacon_claim(smc) ;
381 DB_RMTN(1,"RMT : RM4_NON_OP_DUP\n",0,0) ;
382 ACTIONS_DONE() ;
383 break ;
384 case RM4_NON_OP_DUP :
385 if (cmd == RM_TIMEOUT_POLL) {
386 start_rmt_timer2(smc,smc->s.rmt_t_poll,RM_TIMEOUT_POLL);
387 sm_mac_check_beacon_claim(smc) ;
388 break ;
390 /*RM41*/
391 if (!smc->r.da_flag) {
392 GO_STATE(RM1_NON_OP) ;
393 break ;
395 /*RM44a*/
396 else if ((cmd == RM_MY_BEACON || cmd == RM_OTHER_BEACON) &&
397 smc->r.bn_flag) {
398 smc->r.bn_flag = FALSE ;
400 /*RM44b*/
401 else if (cmd == RM_TRT_EXP && !smc->r.bn_flag) {
402 int tx ;
404 * set bn_flag only if in state T4 or T5:
405 * only if we're the beaconer should we start the
406 * trace !
408 if ((tx = sm_mac_get_tx_state(smc)) == 4 || tx == 5) {
409 DB_RMTN(2,"RMT : NOPDUP && TRT_EXPIRED && T4/T5\n",0,0);
410 smc->r.bn_flag = TRUE ;
412 * If one of the upstream stations beaconed
413 * and the link to the upstream neighbor is
414 * lost we need to restart the stuck timer to
415 * check the "stuck beacon" condition.
417 start_rmt_timer1(smc,smc->s.rmt_t_stuck,
418 RM_TIMEOUT_T_STUCK) ;
421 * We do NOT need to clear smc->r.bn_flag in case of
422 * not being in state T4 or T5, because the flag
423 * must be cleared in order to get in this condition.
426 DB_RMTN(2,
427 "RMT : sm_mac_get_tx_state() = %d (bn_flag = %d)\n",
428 tx,smc->r.bn_flag) ;
430 /*RM44c*/
431 else if (cmd == RM_TIMEOUT_ANNOUNCE && !smc->r.bn_flag) {
432 rmt_dup_actions(smc) ;
434 /*RM45*/
435 else if (cmd == RM_RING_OP) {
436 smc->r.no_flag = FALSE ;
437 GO_STATE(RM5_RING_OP_DUP) ;
438 break ;
440 /*RM46*/
441 else if (cmd == RM_TIMEOUT_T_STUCK &&
442 smc->r.rm_join && smc->r.bn_flag) {
443 GO_STATE(RM6_DIRECTED) ;
444 break ;
446 break ;
447 case ACTIONS(RM5_RING_OP_DUP) :
448 stop_rmt_timer0(smc) ;
449 stop_rmt_timer1(smc) ;
450 stop_rmt_timer2(smc) ;
451 DB_RMTN(1,"RMT : RM5_RING_OP_DUP\n",0,0) ;
452 ACTIONS_DONE() ;
453 break;
454 case RM5_RING_OP_DUP :
455 /*RM52*/
456 if (smc->r.dup_addr_test == DA_PASSED) {
457 smc->r.da_flag = FALSE ;
458 GO_STATE(RM2_RING_OP) ;
459 break ;
461 /*RM54*/
462 else if (cmd == RM_RING_NON_OP) {
463 smc->r.jm_flag = FALSE ;
464 smc->r.bn_flag = FALSE ;
465 GO_STATE(RM4_NON_OP_DUP) ;
466 break ;
468 break ;
469 case ACTIONS(RM6_DIRECTED) :
470 start_rmt_timer0(smc,smc->s.rmt_t_direct,RM_TIMEOUT_T_DIRECT) ;
471 stop_rmt_timer1(smc) ;
472 start_rmt_timer2(smc,smc->s.rmt_t_poll,RM_TIMEOUT_POLL) ;
473 sm_ma_control(smc,MA_DIRECTED) ;
474 RS_SET(smc,RS_BEACON) ;
475 DB_RMTN(1,"RMT : RM6_DIRECTED\n",0,0) ;
476 ACTIONS_DONE() ;
477 break ;
478 case RM6_DIRECTED :
479 /*RM63*/
480 if (cmd == RM_TIMEOUT_POLL) {
481 start_rmt_timer2(smc,smc->s.rmt_t_poll,RM_TIMEOUT_POLL);
482 sm_mac_check_beacon_claim(smc) ;
483 #ifndef SUPERNET_3
484 /* Because of problems with the Supernet II chip set
485 * sending of Directed Beacon will stop after 165ms
486 * therefore restart_trt_for_dbcn(smc) will be called
487 * to prevent this.
489 restart_trt_for_dbcn(smc) ;
490 #endif /*SUPERNET_3*/
491 break ;
493 if ((cmd == RM_MY_BEACON || cmd == RM_OTHER_BEACON) &&
494 !smc->r.da_flag) {
495 smc->r.bn_flag = FALSE ;
496 GO_STATE(RM3_DETECT) ;
497 break ;
499 /*RM64*/
500 else if ((cmd == RM_MY_BEACON || cmd == RM_OTHER_BEACON) &&
501 smc->r.da_flag) {
502 smc->r.bn_flag = FALSE ;
503 GO_STATE(RM4_NON_OP_DUP) ;
504 break ;
506 /*RM67*/
507 else if (cmd == RM_TIMEOUT_T_DIRECT) {
508 GO_STATE(RM7_TRACE) ;
509 break ;
511 break ;
512 case ACTIONS(RM7_TRACE) :
513 stop_rmt_timer0(smc) ;
514 stop_rmt_timer1(smc) ;
515 stop_rmt_timer2(smc) ;
516 smc->e.trace_prop |= ENTITY_BIT(ENTITY_MAC) ;
517 queue_event(smc,EVENT_ECM,EC_TRACE_PROP) ;
518 DB_RMTN(1,"RMT : RM7_TRACE\n",0,0) ;
519 ACTIONS_DONE() ;
520 break ;
521 case RM7_TRACE :
522 break ;
523 default:
524 SMT_PANIC(smc,SMT_E0122, SMT_E0122_MSG) ;
525 break;
530 * (jd) RMT duplicate address actions
531 * leave the ring or reinsert just as configured
533 static void rmt_dup_actions(struct s_smc *smc)
535 if (smc->r.jm_flag) {
537 else {
538 if (smc->s.rmt_dup_mac_behavior) {
539 SMT_ERR_LOG(smc,SMT_E0138, SMT_E0138_MSG) ;
540 rmt_reinsert_actions(smc) ;
542 else {
543 SMT_ERR_LOG(smc,SMT_E0135, SMT_E0135_MSG) ;
544 rmt_leave_actions(smc) ;
550 * Reconnect to the Ring
552 static void rmt_reinsert_actions(struct s_smc *smc)
554 queue_event(smc,EVENT_ECM,EC_DISCONNECT) ;
555 queue_event(smc,EVENT_ECM,EC_CONNECT) ;
559 * duplicate address detected
561 static void rmt_new_dup_actions(struct s_smc *smc)
563 smc->r.da_flag = TRUE ;
564 smc->r.bn_flag = FALSE ;
565 smc->r.jm_flag = FALSE ;
567 * we have three options : change address, jam or leave
568 * we leave the ring as default
569 * Optionally it's possible to reinsert after leaving the Ring
570 * but this will not conform with SMT Spec.
572 if (smc->s.rmt_dup_mac_behavior) {
573 SMT_ERR_LOG(smc,SMT_E0138, SMT_E0138_MSG) ;
574 rmt_reinsert_actions(smc) ;
576 else {
577 SMT_ERR_LOG(smc,SMT_E0135, SMT_E0135_MSG) ;
578 rmt_leave_actions(smc) ;
584 * leave the ring
586 static void rmt_leave_actions(struct s_smc *smc)
588 queue_event(smc,EVENT_ECM,EC_DISCONNECT) ;
590 * Note: Do NOT try again later. (with please reconnect)
591 * The station must be left from the ring!
596 * SMT timer interface
597 * start RMT timer 0
599 static void start_rmt_timer0(struct s_smc *smc, u_long value, int event)
601 smc->r.timer0_exp = FALSE ; /* clear timer event flag */
602 smt_timer_start(smc,&smc->r.rmt_timer0,value,EV_TOKEN(EVENT_RMT,event));
606 * SMT timer interface
607 * start RMT timer 1
609 static void start_rmt_timer1(struct s_smc *smc, u_long value, int event)
611 smc->r.timer1_exp = FALSE ; /* clear timer event flag */
612 smt_timer_start(smc,&smc->r.rmt_timer1,value,EV_TOKEN(EVENT_RMT,event));
616 * SMT timer interface
617 * start RMT timer 2
619 static void start_rmt_timer2(struct s_smc *smc, u_long value, int event)
621 smc->r.timer2_exp = FALSE ; /* clear timer event flag */
622 smt_timer_start(smc,&smc->r.rmt_timer2,value,EV_TOKEN(EVENT_RMT,event));
626 * SMT timer interface
627 * stop RMT timer 0
629 static void stop_rmt_timer0(struct s_smc *smc)
631 if (smc->r.rmt_timer0.tm_active)
632 smt_timer_stop(smc,&smc->r.rmt_timer0) ;
636 * SMT timer interface
637 * stop RMT timer 1
639 static void stop_rmt_timer1(struct s_smc *smc)
641 if (smc->r.rmt_timer1.tm_active)
642 smt_timer_stop(smc,&smc->r.rmt_timer1) ;
646 * SMT timer interface
647 * stop RMT timer 2
649 static void stop_rmt_timer2(struct s_smc *smc)
651 if (smc->r.rmt_timer2.tm_active)
652 smt_timer_stop(smc,&smc->r.rmt_timer2) ;