diff options
Diffstat (limited to 'arch/m68knommu/platform/5307/timers.c')
-rw-r--r-- | arch/m68knommu/platform/5307/timers.c | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/arch/m68knommu/platform/5307/timers.c b/arch/m68knommu/platform/5307/timers.c new file mode 100644 index 000000000000..ef49596aa09c --- /dev/null +++ b/arch/m68knommu/platform/5307/timers.c @@ -0,0 +1,138 @@ +/***************************************************************************/ + +/* + * timers.c -- generic ColdFire hardware timer support. + * + * Copyright (C) 1999-2003, Greg Ungerer (gerg@snapgear.com) + */ + +/***************************************************************************/ + +#include <linux/config.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/param.h> +#include <linux/interrupt.h> +#include <linux/init.h> +#include <asm/irq.h> +#include <asm/traps.h> +#include <asm/machdep.h> +#include <asm/coldfire.h> +#include <asm/mcftimer.h> +#include <asm/mcfsim.h> + +/***************************************************************************/ + +/* + * Default the timer and vector to use for ColdFire. Some ColdFire + * CPU's and some boards may want different. Their sub-architecture + * startup code (in config.c) can change these if they want. + */ +unsigned int mcf_timervector = 29; +unsigned int mcf_profilevector = 31; +unsigned int mcf_timerlevel = 5; + +static volatile struct mcftimer *mcf_timerp; + +/* + * These provide the underlying interrupt vector support. + * Unfortunately it is a little different on each ColdFire. + */ +extern void mcf_settimericr(int timer, int level); +extern int mcf_timerirqpending(int timer); + +/***************************************************************************/ + +void coldfire_tick(void) +{ + /* Reset the ColdFire timer */ + mcf_timerp->ter = MCFTIMER_TER_CAP | MCFTIMER_TER_REF; +} + +/***************************************************************************/ + +void coldfire_timer_init(irqreturn_t (*handler)(int, void *, struct pt_regs *)) +{ + /* Set up an internal TIMER as poll clock */ + mcf_timerp = (volatile struct mcftimer *) (MCF_MBAR + MCFTIMER_BASE1); + mcf_timerp->tmr = MCFTIMER_TMR_DISABLE; + + mcf_timerp->trr = (unsigned short) ((MCF_BUSCLK / 16) / HZ); + mcf_timerp->tmr = MCFTIMER_TMR_ENORI | MCFTIMER_TMR_CLK16 | + MCFTIMER_TMR_RESTART | MCFTIMER_TMR_ENABLE; + + request_irq(mcf_timervector, handler, SA_INTERRUPT, "timer", NULL); + mcf_settimericr(1, mcf_timerlevel); + +#ifdef CONFIG_HIGHPROFILE + coldfire_profile_init(); +#endif +} + +/***************************************************************************/ + +unsigned long coldfire_timer_offset(void) +{ + unsigned long trr, tcn, offset; + + /* + * The change to pointer and de-reference is to force the compiler + * to read the registers with a single 16bit access. Otherwise it + * does some crazy 8bit read combining. + */ + tcn = *(&mcf_timerp->tcn); + trr = *(&mcf_timerp->trr); + offset = (tcn * (1000000 / HZ)) / trr; + + /* Check if we just wrapped the counters and maybe missed a tick */ + if ((offset < (1000000 / HZ / 2)) && mcf_timerirqpending(1)) + offset += 1000000 / HZ; + return offset; +} + +/***************************************************************************/ +#ifdef CONFIG_HIGHPROFILE +/***************************************************************************/ + +/* + * Choose a reasonably fast profile timer. Make it an odd value to + * try and get good coverage of kernal operations. + */ +#define PROFILEHZ 1013 + +static volatile struct mcftimer *mcf_proftp; + +/* + * Use the other timer to provide high accuracy profiling info. + */ + +void coldfire_profile_tick(int irq, void *dummy, struct pt_regs *regs) +{ + /* Reset ColdFire timer2 */ + mcf_proftp->ter = MCFTIMER_TER_CAP | MCFTIMER_TER_REF; + if (current->pid) + profile_tick(CPU_PROFILING, regs); +} + +/***************************************************************************/ + +void coldfire_profile_init(void) +{ + printk(KERN_INFO "PROFILE: lodging TIMER2 @ %dHz as profile timer\n", PROFILEHZ); + + /* Set up TIMER 2 as high speed profile clock */ + mcf_proftp = (volatile struct mcftimer *) (MCF_MBAR + MCFTIMER_BASE2); + mcf_proftp->tmr = MCFTIMER_TMR_DISABLE; + + mcf_proftp->trr = (unsigned short) ((MCF_CLK / 16) / PROFILEHZ); + mcf_proftp->tmr = MCFTIMER_TMR_ENORI | MCFTIMER_TMR_CLK16 | + MCFTIMER_TMR_RESTART | MCFTIMER_TMR_ENABLE; + + request_irq(mcf_profilevector, coldfire_profile_tick, + (SA_INTERRUPT | IRQ_FLG_FAST), "profile timer", NULL); + mcf_settimericr(2, 7); +} + +/***************************************************************************/ +#endif /* CONFIG_HIGHPROFILE */ +/***************************************************************************/ |