NetBSD-5.0.2/sys/arch/mac68k/mac68k/clock.c
/* $NetBSD: clock.c,v 1.47 2008/07/22 14:43:45 hauke Exp $ */
/*
* Copyright (c) 1982, 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* 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. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 THE REGENTS OR CONTRIBUTORS 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.
*/
/*
* Copyright (c) 1988 University of Utah.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* 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 by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 THE REGENTS OR CONTRIBUTORS 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.
*/
/*-
* Copyright (C) 1993 Allen K. Briggs, Chris P. Caputo,
* Michael L. Finch, Bradley A. Grantham, and
* Lawrence A. Kesteloot
* All rights reserved.
*
* 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 by the Alice Group.
* 4. The names of the Alice Group or any of its members may not be used
* to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE ALICE GROUP ``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 THE ALICE GROUP 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.
*
*/
/*
*
* from: Utah $Hdr: clock.c 1.18 91/01/21$
*
* @(#)clock.c 7.6 (Berkeley) 5/7/91
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: clock.c,v 1.47 2008/07/22 14:43:45 hauke Exp $");
#include <sys/param.h>
#include <sys/device.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <sys/timetc.h>
#include <dev/clock_subr.h>
#include <machine/autoconf.h>
#include <machine/psl.h>
#include <machine/cpu.h>
#include <machine/limits.h>
#if defined(GPROF) && defined(PROFTIMER)
#include <sys/gprof.h>
#endif
#include <mac68k/mac68k/pram.h>
#include <mac68k/mac68k/clockreg.h>
#include <machine/viareg.h>
#ifdef DEBUG
int clock_debug = 0;
#endif
void rtclock_intr(void);
static int mac68k_gettime(todr_chip_handle_t, volatile struct timeval *);
static int mac68k_settime(todr_chip_handle_t, volatile struct timeval *);
static u_int via1_t2_get_timecount(struct timecounter *);
#define DIFF19041970 2082844800
#define DIFF19701990 630720000
#define DIFF19702010 1261440000
/*
* Mac II machine-dependent clock routines.
*/
/*
* Start the real-time clock; i.e. set timer latches and boot timer.
*
* We use VIA1 timer 1.
*/
void
startrtclock(void)
{
/*
* BARF MF startrt clock is called twice in init_main, configure,
* the reason why is doced in configure
*/
/* be certain all clock interrupts are off */
via_reg(VIA1, vIER) = V1IF_T1 | V1IF_T2;
/* set timer latch */
via_reg(VIA1, vACR) |= ACR_T1LATCH;
/* set VIA timer 1 latch to 60 Hz (100 Hz) */
via_reg(VIA1, vT1L) = CLK_INTL;
via_reg(VIA1, vT1LH) = CLK_INTH;
/* set VIA timer 1 counter started for 60(100) Hz */
via_reg(VIA1, vT1C) = CLK_INTL;
via_reg(VIA1, vT1CH) = CLK_INTH;
/*
* Set & start VIA1 timer 2 free-running for timecounter support.
* Since reading the LSB of the counter clears any pending
* interrupt, timer 1 is less suitable as a timecounter.
*/
via_reg(VIA1, vT2C) = 0x0ff;
via_reg(VIA1, vT2CH) = 0x0ff;
}
void
enablertclock(void)
{
/* clear then enable clock interrupt. */
via_reg(VIA1, vIFR) |= V1IF_T1;
via_reg(VIA1, vIER) = 0x80 | V1IF_T1;
}
void
cpu_initclocks(void)
{
static struct todr_chip_handle todr = {
.todr_settime = mac68k_settime,
.todr_gettime = mac68k_gettime,
};
static struct timecounter via1_t2_timecounter = {
.tc_get_timecount = via1_t2_get_timecount,
.tc_poll_pps = 0,
.tc_counter_mask = 0x0ffffu,
.tc_frequency = CLK_FREQ,
.tc_name = "VIA1 T2",
.tc_quality = 100,
.tc_priv = NULL,
.tc_next = NULL
};
enablertclock();
todr_attach(&todr);
tc_init(&via1_t2_timecounter);
}
void
setstatclockrate(int rateinhz)
{
}
void
disablertclock(void)
{
/* disable clock interrupt */
via_reg(VIA1, vIER) = V1IF_T1;
}
static u_int
via1_t2_get_timecount(struct timecounter *tc)
{
uint8_t high, high2, low;
int s;
/* Guard HW timer access */
s = splhigh();
high = via_reg(VIA1, vT2CH);
low = via_reg(VIA1, vT2C);
high2 = via_reg(VIA1, vT2CH);
/*
* If we find that the MSB has just been incremented, read
* the LSB again, to avoid a race that could leave us with a new
* MSB and an old LSB value.
* With timecounters, the difference is quite spectacular.
*
* is added that to port-amiga ten years ago. Thanks!
*/
if (high != high2) {
low = via_reg(VIA1, vT2C);
high = high2;
}
splx(s);
return 0x0ffff - ((high << 8) | low);
}
#ifdef PROFTIMER
/*
* Here, we have implemented code that causes VIA2's timer to count
* the profiling clock. Following the HP300's lead, this reduces
* the impact on other tasks, since locore turns off the profiling clock
* on context switches. If need be, the profiling clock's resolution can
* be cranked higher than the real-time clock's resolution, to prevent
* aliasing and allow higher accuracy.
*/
int profint = PRF_INTERVAL; /* Clock ticks between interrupts */
int profinthigh;
int profintlow;
int profscale = 0; /* Scale factor from sys clock to prof clock */
char profon = 0; /* Is profiling clock on? */
/* profon values - do not change, locore.s assumes these values */
#define PRF_NONE 0x00
#define PRF_USER 0x01
#define PRF_KERNEL 0x80
void
initprofclock(void)
{
/* profile interval must be even divisor of system clock interval */
if (profint > CLK_INTERVAL)
profint = CLK_INTERVAL;
else
if (CLK_INTERVAL % profint != 0)
/* try to intelligently fix clock interval */
profint = CLK_INTERVAL / (CLK_INTERVAL / profint);
profscale = CLK_INTERVAL / profint;
profinthigh = profint >> 8;
profintlow = profint & 0xff;
}
void
startprofclock(void)
{
via_reg(VIA2, vT1L) = (profint - 1) & 0xff;
via_reg(VIA2, vT1LH) = (profint - 1) >> 8;
via_reg(VIA2, vACR) |= ACR_T1LATCH;
via_reg(VIA2, vT1C) = (profint - 1) & 0xff;
via_reg(VIA2, vT1CH) = (profint - 1) >> 8;
}
void
stopprofclock(void)
{
via_reg(VIA2, vT1L) = 0;
via_reg(VIA2, vT1LH) = 0;
via_reg(VIA2, vT1C) = 0;
via_reg(VIA2, vT1CH) = 0;
}
#ifdef GPROF
/*
* BARF: we should check this:
*
* profclock() is expanded in line in lev6intr() unless profiling kernel.
* Assumes it is called with clock interrupts blocked.
*/
void
profclock(clockframe *pclk)
{
/*
* Came from user mode.
* If this process is being profiled record the tick.
*/
if (USERMODE(pclk->ps)) {
if (curproc->p_stats.p_prof.pr_scale)
addupc_task(&curproc, pclk->pc, 1);
}
/*
* Came from kernel (supervisor) mode.
* If we are profiling the kernel, record the tick.
*/
else
if (profiling < 2) {
int s = pclk->pc - s_lowpc;
if (s < s_textsize)
kcount[s / (HISTFRACTION * sizeof(*kcount))]++;
}
/*
* Kernel profiling was on but has been disabled.
* Mark as no longer profiling kernel and if all profiling done,
* disable the clock.
*/
if (profiling && (profon & PRF_KERNEL)) {
profon &= ~PRF_KERNEL;
if (profon == PRF_NONE)
stopprofclock();
}
}
#endif
#endif
static u_long ugmt_2_pramt(u_long);
static u_long pramt_2_ugmt(u_long);
/*
* Convert GMT to Mac PRAM time, using rtc_offset
* GMT bias adjustment is done elsewhere.
*/
static u_long
ugmt_2_pramt(u_long t)
{
/* don't know how to open a file properly. */
/* assume compiled timezone is correct. */
return (t = t + DIFF19041970);
}
/*
* Convert a Mac PRAM time value to GMT, using rtc_offset
* GMT bias adjustment is done elsewhere.
*/
static u_long
pramt_2_ugmt(u_long t)
{
return (t = t - DIFF19041970);
}
/*
* Time from the booter.
*/
u_long macos_boottime;
/*
* Bias in minutes east from GMT (also from booter).
*/
long macos_gmtbias;
/*
* Flag for whether or not we can trust the PRAM. If we don't
* trust it, we don't write to it, and we take the MacOS value
* that is passed from the booter (which will only be a second
* or two off by now).
*/
int mac68k_trust_pram = 1;
/*
* Set global GMT time register, using a file system time base for comparison
* and sanity checking.
*/
int
mac68k_gettime(todr_chip_handle_t tch, volatile struct timeval *tvp)
{
u_long timbuf;
timbuf = pramt_2_ugmt(pram_readtime());
if ((timbuf - macos_boottime) > 10 * 60) {
#if DIAGNOSTIC
printf(
"PRAM time does not appear to have been read correctly.\n");
printf("PRAM: 0x%lx, macos_boottime: 0x%lx.\n",
timbuf, macos_boottime);
#endif
timbuf = macos_boottime;
mac68k_trust_pram = 0;
}
tvp->tv_sec = timbuf;
tvp->tv_usec = 0;
return 0;
}
int
mac68k_settime(todr_chip_handle_t tch, volatile struct timeval *tvp)
{
if (mac68k_trust_pram)
/*
* GMT bias is passed in from the Booter.
* To get *our* time, add GMTBIAS to GMT.
* (gmtbias is in minutes, multiply by 60).
*/
pram_settime(ugmt_2_pramt(tvp->tv_sec + macos_gmtbias * 60));
#ifdef DEBUG
else if (clock_debug)
printf("NetBSD/mac68k does not trust itself to try and write "
"to the PRAM on this system.\n");
#endif
return 0;
}
/*
* The Macintosh timers decrement once every 1.2766 microseconds.
* MGFH2, p. 180
*/
#define CLK_RATE 12766
#define DELAY_CALIBRATE (0xffffff << 7) /* Large value for calibration */
u_int delay_factor = DELAY_CALIBRATE;
volatile int delay_flag = 1;
int _delay(u_int);
static void delay_timer1_irq(void *);
static void
delay_timer1_irq(void *dummy)
{
delay_flag = 0;
}
/*
* Calibrate delay_factor with VIA1 timer T1.
*/
void
mac68k_calibrate_delay(void)
{
u_int sum, n;
(void)spl0();
/* Disable VIA1 timer 1 interrupts and set up service routine */
via_reg(VIA1, vIER) = V1IF_T1;
via1_register_irq(VIA1_T1, delay_timer1_irq, NULL);
/* Set the timer for one-shot mode, then clear and enable interrupts */
via_reg(VIA1, vACR) &= ~ACR_T1LATCH;
via_reg(VIA1, vIFR) = V1IF_T1; /* (this is needed for IIsi) */
via_reg(VIA1, vIER) = 0x80 | V1IF_T1;
#ifdef DEBUG
if (clock_debug)
printf("mac68k_calibrate_delay(): entering timing loop\n");
#endif
for (sum = 0, n = 8; n > 0; n--) {
delay_flag = 1;
via_reg(VIA1, vT1C) = 0; /* 1024 clock ticks */
via_reg(VIA1, vT1CH) = 4; /* (approx 1.3 msec) */
sum += ((delay_factor >> 7) - _delay(1));
}
/* Disable timer interrupts and reset service routine */
via_reg(VIA1, vIER) = V1IF_T1;
via1_register_irq(VIA1_T1, (void (*)(void *))rtclock_intr, NULL);
/*
* If this weren't integer math, the following would look
* a lot prettier. It should really be something like
* this:
* delay_factor = ((sum / 8) / (1024 * 1.2766)) * 128;
* That is, average the sum, divide by the number of usec,
* and multiply by a scale factor of 128.
*
* We can accomplish the same thing by simplifying and using
* shifts, being careful to avoid as much loss of precision
* as possible. (If the sum exceeds UINT_MAX/10000, we need
* to rearrange the calculation slightly to do this.)
*/
if (sum > (UINT_MAX / 10000)) /* This is a _fast_ machine! */
delay_factor = (((sum >> 3) * 10000) / CLK_RATE) >> 3;
else
delay_factor = (((sum * 10000) >> 3) / CLK_RATE) >> 3;
/* Reset the delay_flag for normal use */
delay_flag = 1;
#ifdef DEBUG
if (clock_debug)
printf("mac68k_calibrate_delay(): delay_factor calibrated\n");
#endif
(void)splhigh();
}