diff options
Diffstat (limited to 'drivers/net/fddi/skfp/hwt.c')
| -rw-r--r-- | drivers/net/fddi/skfp/hwt.c | 269 |
1 files changed, 269 insertions, 0 deletions
diff --git a/drivers/net/fddi/skfp/hwt.c b/drivers/net/fddi/skfp/hwt.c new file mode 100644 index 000000000000..c0798fd2ca69 --- /dev/null +++ b/drivers/net/fddi/skfp/hwt.c @@ -0,0 +1,269 @@ +/****************************************************************************** + * + * (C)Copyright 1998,1999 SysKonnect, + * a business unit of Schneider & Koch & Co. Datensysteme GmbH. + * + * See the file "skfddi.c" for further information. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * The information in this file is provided "AS IS" without warranty. + * + ******************************************************************************/ + +/* + * Timer Driver for FBI board (timer chip 82C54) + */ + +/* + * Modifications: + * + * 28-Jun-1994 sw Edit v1.6. + * MCA: Added support for the SK-NET FDDI-FM2 adapter. The + * following functions have been added(+) or modified(*): + * hwt_start(*), hwt_stop(*), hwt_restart(*), hwt_read(*) + */ + +#include "h/types.h" +#include "h/fddi.h" +#include "h/smc.h" + +#ifndef lint +static const char ID_sccs[] = "@(#)hwt.c 1.13 97/04/23 (C) SK " ; +#endif + +/* + * Prototypes of local functions. + */ +/* 28-Jun-1994 sw - Note: hwt_restart() is also used in module 'drvfbi.c'. */ +/*static void hwt_restart() ; */ + +/************************ + * + * hwt_start + * + * Start hardware timer (clock ticks are 16us). + * + * void hwt_start( + * struct s_smc *smc, + * u_long time) ; + * In + * smc - A pointer to the SMT Context structure. + * + * time - The time in units of 16us to load the timer with. + * Out + * Nothing. + * + ************************/ +#define HWT_MAX (65000) + +void hwt_start(struct s_smc *smc, u_long time) +{ + u_short cnt ; + + if (time > HWT_MAX) + time = HWT_MAX ; + + smc->hw.t_start = time ; + smc->hw.t_stop = 0L ; + + cnt = (u_short)time ; + /* + * if time < 16 us + * time = 16 us + */ + if (!cnt) + cnt++ ; + + outpd(ADDR(B2_TI_INI), (u_long) cnt * 200) ; /* Load timer value. */ + outpw(ADDR(B2_TI_CRTL), TIM_START) ; /* Start timer. */ + + smc->hw.timer_activ = TRUE ; +} + +/************************ + * + * hwt_stop + * + * Stop hardware timer. + * + * void hwt_stop( + * struct s_smc *smc) ; + * In + * smc - A pointer to the SMT Context structure. + * Out + * Nothing. + * + ************************/ +void hwt_stop(struct s_smc *smc) +{ + outpw(ADDR(B2_TI_CRTL), TIM_STOP) ; + outpw(ADDR(B2_TI_CRTL), TIM_CL_IRQ) ; + + smc->hw.timer_activ = FALSE ; +} + +/************************ + * + * hwt_init + * + * Initialize hardware timer. + * + * void hwt_init( + * struct s_smc *smc) ; + * In + * smc - A pointer to the SMT Context structure. + * Out + * Nothing. + * + ************************/ +void hwt_init(struct s_smc *smc) +{ + smc->hw.t_start = 0 ; + smc->hw.t_stop = 0 ; + smc->hw.timer_activ = FALSE ; + + hwt_restart(smc) ; +} + +/************************ + * + * hwt_restart + * + * Clear timer interrupt. + * + * void hwt_restart( + * struct s_smc *smc) ; + * In + * smc - A pointer to the SMT Context structure. + * Out + * Nothing. + * + ************************/ +void hwt_restart(struct s_smc *smc) +{ + hwt_stop(smc) ; +} + +/************************ + * + * hwt_read + * + * Stop hardware timer and read time elapsed since last start. + * + * u_long hwt_read(smc) ; + * In + * smc - A pointer to the SMT Context structure. + * Out + * The elapsed time since last start in units of 16us. + * + ************************/ +u_long hwt_read(struct s_smc *smc) +{ + u_short tr ; + u_long is ; + + if (smc->hw.timer_activ) { + hwt_stop(smc) ; + tr = (u_short)((inpd(ADDR(B2_TI_VAL))/200) & 0xffff) ; + + is = GET_ISR() ; + /* Check if timer expired (or wraparound). */ + if ((tr > smc->hw.t_start) || (is & IS_TIMINT)) { + hwt_restart(smc) ; + smc->hw.t_stop = smc->hw.t_start ; + } + else + smc->hw.t_stop = smc->hw.t_start - tr ; + } + return smc->hw.t_stop; +} + +#ifdef PCI +/************************ + * + * hwt_quick_read + * + * Stop hardware timer and read timer value and start the timer again. + * + * u_long hwt_read(smc) ; + * In + * smc - A pointer to the SMT Context structure. + * Out + * current timer value in units of 80ns. + * + ************************/ +u_long hwt_quick_read(struct s_smc *smc) +{ + u_long interval ; + u_long time ; + + interval = inpd(ADDR(B2_TI_INI)) ; + outpw(ADDR(B2_TI_CRTL), TIM_STOP) ; + time = inpd(ADDR(B2_TI_VAL)) ; + outpd(ADDR(B2_TI_INI),time) ; + outpw(ADDR(B2_TI_CRTL), TIM_START) ; + outpd(ADDR(B2_TI_INI),interval) ; + + return time; +} + +/************************ + * + * hwt_wait_time(smc,start,duration) + * + * This function returnes after the amount of time is elapsed + * since the start time. + * + * para start start time + * duration time to wait + * + * NOTE: The function will return immediately, if the timer is not + * started + ************************/ +void hwt_wait_time(struct s_smc *smc, u_long start, long int duration) +{ + long diff ; + long interval ; + int wrapped ; + + /* + * check if timer is running + */ + if (smc->hw.timer_activ == FALSE || + hwt_quick_read(smc) == hwt_quick_read(smc)) { + return ; + } + + interval = inpd(ADDR(B2_TI_INI)) ; + if (interval > duration) { + do { + diff = (long)(start - hwt_quick_read(smc)) ; + if (diff < 0) { + diff += interval ; + } + } while (diff <= duration) ; + } + else { + diff = interval ; + wrapped = 0 ; + do { + if (!wrapped) { + if (hwt_quick_read(smc) >= start) { + diff += interval ; + wrapped = 1 ; + } + } + else { + if (hwt_quick_read(smc) < start) { + wrapped = 0 ; + } + } + } while (diff <= duration) ; + } +} +#endif + |