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1// SPDX-License-Identifier: GPL-2.0-or-later2/******************************************************************************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 timer15*/16 17#include "h/types.h"18#include "h/fddi.h"19#include "h/smc.h"20 21static void timer_done(struct s_smc *smc, int restart);22 23void smt_timer_init(struct s_smc *smc)24{25	smc->t.st_queue = NULL;26	smc->t.st_fast.tm_active = FALSE ;27	smc->t.st_fast.tm_next = NULL;28	hwt_init(smc) ;29}30 31void smt_timer_stop(struct s_smc *smc, struct smt_timer *timer)32{33	struct smt_timer	**prev ;34	struct smt_timer	*tm ;35 36	/*37	 * remove timer from queue38	 */39	timer->tm_active = FALSE ;40	if (smc->t.st_queue == timer && !timer->tm_next) {41		hwt_stop(smc) ;42	}43	for (prev = &smc->t.st_queue ; (tm = *prev) ; prev = &tm->tm_next ) {44		if (tm == timer) {45			*prev = tm->tm_next ;46			if (tm->tm_next) {47				tm->tm_next->tm_delta += tm->tm_delta ;48			}49			return ;50		}51	}52}53 54void smt_timer_start(struct s_smc *smc, struct smt_timer *timer, u_long time,55		     u_long token)56{57	struct smt_timer	**prev ;58	struct smt_timer	*tm ;59	u_long			delta = 0 ;60 61	time /= 16 ;		/* input is uS, clock ticks are 16uS */62	if (!time)63		time = 1 ;64	smt_timer_stop(smc,timer) ;65	timer->tm_smc = smc ;66	timer->tm_token = token ;67	timer->tm_active = TRUE ;68	if (!smc->t.st_queue) {69		smc->t.st_queue = timer ;70		timer->tm_next = NULL;71		timer->tm_delta = time ;72		hwt_start(smc,time) ;73		return ;74	}75	/*76	 * timer correction77	 */78	timer_done(smc,0) ;79 80	/*81	 * find position in queue82	 */83	delta = 0 ;84	for (prev = &smc->t.st_queue ; (tm = *prev) ; prev = &tm->tm_next ) {85		if (delta + tm->tm_delta > time) {86			break ;87		}88		delta += tm->tm_delta ;89	}90	/* insert in queue */91	*prev = timer ;92	timer->tm_next = tm ;93	timer->tm_delta = time - delta ;94	if (tm)95		tm->tm_delta -= timer->tm_delta ;96	/*97	 * start new with first98	 */99	hwt_start(smc,smc->t.st_queue->tm_delta) ;100}101 102void smt_force_irq(struct s_smc *smc)103{104	smt_timer_start(smc,&smc->t.st_fast,32L, EV_TOKEN(EVENT_SMT,SM_FAST)); 105}106 107void smt_timer_done(struct s_smc *smc)108{109	timer_done(smc,1) ;110}111 112static void timer_done(struct s_smc *smc, int restart)113{114	u_long			delta ;115	struct smt_timer	*tm ;116	struct smt_timer	*next ;117	struct smt_timer	**last ;118	int			done = 0 ;119 120	delta = hwt_read(smc) ;121	last = &smc->t.st_queue ;122	tm = smc->t.st_queue ;123	while (tm && !done) {124		if (delta >= tm->tm_delta) {125			tm->tm_active = FALSE ;126			delta -= tm->tm_delta ;127			last = &tm->tm_next ;128			tm = tm->tm_next ;129		}130		else {131			tm->tm_delta -= delta ;132			delta = 0 ;133			done = 1 ;134		}135	}136	*last = NULL;137	next = smc->t.st_queue ;138	smc->t.st_queue = tm ;139 140	for ( tm = next ; tm ; tm = next) {141		next = tm->tm_next ;142		timer_event(smc,tm->tm_token) ;143	}144 145	if (restart && smc->t.st_queue)146		hwt_start(smc,smc->t.st_queue->tm_delta) ;147}148 149