/* $NetBSD: i80321_timer.c,v 1.9 2005/02/26 12:00:52 simonb Exp $ */ /* * Copyright (c) 2001, 2002 Wasabi Systems, Inc. * All rights reserved. * * Written by Jason R. Thorpe for Wasabi Systems, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed for the NetBSD Project by * Wasabi Systems, Inc. * 4. The name of Wasabi Systems, Inc. may not be used to endorse * or promote products derived from this software without specific prior * written permission. * * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * Timer/clock support for the Intel i80321 I/O processor. */ #include __KERNEL_RCSID(0, "$NetBSD: i80321_timer.c,v 1.9 2005/02/26 12:00:52 simonb Exp $"); #include "opt_perfctrs.h" #include "opt_i80321.h" #include #include #include #include #include #include #include #include #include #include void (*i80321_hardclock_hook)(void); #ifndef COUNTS_PER_SEC #define COUNTS_PER_SEC 200000000 /* 200MHz */ #endif #define COUNTS_PER_USEC (COUNTS_PER_SEC / 1000000) static void *clock_ih; static uint32_t counts_per_hz; int clockhandler(void *); static __inline uint32_t tmr0_read(void) { uint32_t rv; __asm __volatile("mrc p6, 0, %0, c0, c1, 0" : "=r" (rv)); return (rv); } static __inline void tmr0_write(uint32_t val) { __asm __volatile("mcr p6, 0, %0, c0, c1, 0" : : "r" (val)); } static __inline uint32_t tcr0_read(void) { uint32_t rv; __asm __volatile("mrc p6, 0, %0, c2, c1, 0" : "=r" (rv)); return (rv); } static __inline void tcr0_write(uint32_t val) { __asm __volatile("mcr p6, 0, %0, c2, c1, 0" : : "r" (val)); } static __inline void trr0_write(uint32_t val) { __asm __volatile("mcr p6, 0, %0, c4, c1, 0" : : "r" (val)); } static __inline void tisr_write(uint32_t val) { __asm __volatile("mcr p6, 0, %0, c6, c1, 0" : : "r" (val)); } /* * i80321_calibrate_delay: * * Calibrate the delay loop. */ void i80321_calibrate_delay(void) { /* * Just use hz=100 for now -- we'll adjust it, if necessary, * in cpu_initclocks(). */ counts_per_hz = COUNTS_PER_SEC / 100; tmr0_write(0); /* stop timer */ tisr_write(TISR_TMR0); /* clear interrupt */ trr0_write(counts_per_hz); /* reload value */ tcr0_write(counts_per_hz); /* current value */ tmr0_write(TMRx_ENABLE|TMRx_RELOAD|TMRx_CSEL_CORE); } /* * cpu_initclocks: * * Initialize the clock and get them going. */ void cpu_initclocks(void) { u_int oldirqstate; #if defined(PERFCTRS) void *pmu_ih; #endif if (hz < 50 || COUNTS_PER_SEC % hz) { aprint_error("Cannot get %d Hz clock; using 100 Hz\n", hz); hz = 100; } tick = 1000000 / hz; /* number of microseconds between interrupts */ tickfix = 1000000 - (hz * tick); if (tickfix) { int ftp; ftp = min(ffs(tickfix), ffs(hz)); tickfix >>= (ftp - 1); tickfixinterval = hz >> (ftp - 1); } /* * We only have one timer available; stathz and profhz are * always left as 0 (the upper-layer clock code deals with * this situation). */ if (stathz != 0) aprint_error("Cannot get %d Hz statclock\n", stathz); stathz = 0; if (profhz != 0) aprint_error("Cannot get %d Hz profclock\n", profhz); profhz = 0; /* Report the clock frequency. */ aprint_normal("clock: hz=%d stathz=%d profhz=%d\n", hz, stathz, profhz); oldirqstate = disable_interrupts(I32_bit); /* Hook up the clock interrupt handler. */ clock_ih = i80321_intr_establish(ICU_INT_TMR0, IPL_CLOCK, clockhandler, NULL); if (clock_ih == NULL) panic("cpu_initclocks: unable to register timer interrupt"); #if defined(PERFCTRS) pmu_ih = i80321_intr_establish(ICU_INT_PMU, IPL_STATCLOCK, xscale_pmc_dispatch, NULL); if (pmu_ih == NULL) panic("cpu_initclocks: unable to register timer interrupt"); #endif /* Set up the new clock parameters. */ tmr0_write(0); /* stop timer */ tisr_write(TISR_TMR0); /* clear interrupt */ counts_per_hz = COUNTS_PER_SEC / hz; trr0_write(counts_per_hz); /* reload value */ tcr0_write(counts_per_hz); /* current value */ tmr0_write(TMRx_ENABLE|TMRx_RELOAD|TMRx_CSEL_CORE); restore_interrupts(oldirqstate); } /* * setstatclockrate: * * Set the rate of the statistics clock. * * We assume that hz is either stathz or profhz, and that neither * will change after being set by cpu_initclocks(). We could * recalculate the intervals here, but that would be a pain. */ void setstatclockrate(int hz) { /* * XXX Use TMR1? */ } /* * microtime: * * Fill in the specified timeval struct with the current time * accurate to the microsecond. */ void microtime(struct timeval *tvp) { static struct timeval lasttv; u_int oldirqstate; uint32_t counts; oldirqstate = disable_interrupts(I32_bit); counts = counts_per_hz - tcr0_read(); /* Fill in the timeval struct. */ *tvp = time; tvp->tv_usec += (counts / COUNTS_PER_USEC); /* Make sure microseconds doesn't overflow. */ while (tvp->tv_usec >= 1000000) { tvp->tv_usec -= 1000000; tvp->tv_sec++; } /* Make sure the time has advanced. */ if (tvp->tv_sec == lasttv.tv_sec && tvp->tv_usec <= lasttv.tv_usec) { tvp->tv_usec = lasttv.tv_usec + 1; if (tvp->tv_usec >= 1000000) { tvp->tv_usec -= 1000000; tvp->tv_sec++; } } lasttv = *tvp; restore_interrupts(oldirqstate); } /* * delay: * * Delay for at least N microseconds. */ void delay(u_int n) { uint32_t cur, last, delta, usecs; /* * This works by polling the timer and counting the * number of microseconds that go by. */ last = tcr0_read(); delta = usecs = 0; while (n > usecs) { cur = tcr0_read(); /* Check to see if the timer has wrapped around. */ if (last < cur) delta += (last + (counts_per_hz - cur)); else delta += (last - cur); last = cur; if (delta >= COUNTS_PER_USEC) { usecs += delta / COUNTS_PER_USEC; delta %= COUNTS_PER_USEC; } } } todr_chip_handle_t todr_handle; /* * todr_attach: * * Set the specified time-of-day register as the system real-time clock. */ void todr_attach(todr_chip_handle_t todr) { if (todr_handle) panic("todr_attach: rtc already configured"); todr_handle = todr; } /* * inittodr: * * Initialize time from the time-of-day register. */ #define MINYEAR 2003 /* minimum plausible year */ void inittodr(time_t base) { time_t deltat; int badbase; if (base < (MINYEAR - 1970) * SECYR) { printf("WARNING: preposterous time in file system"); /* read the system clock anyway */ base = (MINYEAR - 1970) * SECYR; badbase = 1; } else badbase = 0; if (todr_handle == NULL || todr_gettime(todr_handle, (struct timeval *)&time) != 0 || time.tv_sec == 0) { /* * Believe the time in the file system for lack of * anything better, resetting the TODR. */ time.tv_sec = base; time.tv_usec = 0; if (todr_handle != NULL && !badbase) { printf("WARNING: preposterous clock chip time\n"); resettodr(); } goto bad; } if (!badbase) { /* * See if we gained/lost two or more days; if * so, assume something is amiss. */ deltat = time.tv_sec - base; if (deltat < 0) deltat = -deltat; if (deltat < 2 * SECDAY) return; /* all is well */ printf("WARNING: clock %s %ld days\n", time.tv_sec < base ? "lost" : "gained", (long)deltat / SECDAY); } bad: printf("WARNING: CHECK AND RESET THE DATE!\n"); } /* * resettodr: * * Reset the time-of-day register with the current time. */ void resettodr(void) { if (time.tv_sec == 0) return; if (todr_handle != NULL && todr_settime(todr_handle, (struct timeval *)&time) != 0) printf("resettodr: failed to set time\n"); } /* * clockhandler: * * Handle the hardclock interrupt. */ int clockhandler(void *arg) { struct clockframe *frame = arg; tisr_write(TISR_TMR0); hardclock(frame); if (i80321_hardclock_hook != NULL) (*i80321_hardclock_hook)(); return (1); }