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kernel reorg
[unix-history] / usr / src / sys / hp300 / hp300 / clock.c
/*
* Copyright (c) 1988 University of Utah.
* 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.
*
* %sccs.include.redist.c%
*
* from: Utah $Hdr: clock.c 1.17 89/11/30$
*
* @(#)clock.c 7.4 (Berkeley) %G%
*/
#include "sys/param.h"
#include "sys/user.h"
#include "sys/kernel.h"
#include "../dev/hilreg.h"
#include "clockreg.h"
#include "../include/psl.h"
#include "../include/cpu.h"
#if defined(GPROF) && defined(PROFTIMER)
#include "sys/gprof.h"
#endif
int clkstd[1];
static int month_days[12] = {
31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
};
struct bbc_tm *gmt_to_bbc();
u_char bbc_registers[13];
u_char write_bbc_reg(), read_bbc_reg();
struct hil_dev *bbcaddr = NULL;
/*
* Machine-dependent clock routines.
*
* Startrtclock restarts the real-time clock, which provides
* hardclock interrupts to kern_clock.c.
*
* Inittodr initializes the time of day hardware which provides
* date functions.
*
* Resettodr restores the time of day hardware after a time change.
*
* A note on the real-time clock:
* We actually load the clock with CLK_INTERVAL-1 instead of CLK_INTERVAL.
* This is because the counter decrements to zero after N+1 enabled clock
* periods where N is the value loaded into the counter.
*/
/*
* Start the real-time clock.
*/
startrtclock()
{
register struct clkreg *clk;
clkstd[0] = IOV(0x5F8000);
clk = (struct clkreg *) clkstd[0];
clk->clk_cr2 = CLK_CR1;
clk->clk_cr1 = CLK_RESET;
clk->clk_cr2 = CLK_CR3;
clk->clk_cr3 = 0;
clk->clk_msb1 = (CLK_INTERVAL-1) >> 8 & 0xFF;
clk->clk_lsb1 = (CLK_INTERVAL-1) & 0xFF;
clk->clk_msb2 = 0;
clk->clk_lsb2 = 0;
clk->clk_msb3 = 0;
clk->clk_lsb3 = 0;
clk->clk_cr2 = CLK_CR1;
clk->clk_cr1 = CLK_IENAB;
}
/*
* Returns number of usec since last recorded clock "tick"
* (i.e. clock interrupt).
*/
clkread()
{
register struct clkreg *clk = (struct clkreg *) clkstd[0];
register int high, low;
high = clk->clk_msb1;
low = clk->clk_lsb1;
if (high != clk->clk_msb1)
high = clk->clk_msb1;
high = (CLK_INTERVAL-1) - ((high << 8) | low);
/*
* Pending interrupt indicates that the counter has wrapped
* since we went to splhigh(). Need to compensate.
*/
if (clk->clk_sr & CLK_INT1)
high += CLK_INTERVAL;
return((high * tick) / CLK_INTERVAL);
}
#include "clock.h"
#if NCLOCK > 0
/*
* /dev/clock: mappable high resolution timer.
*
* This code implements a 32-bit recycling counter (with a 4 usec period)
* using timers 2 & 3 on the 6840 clock chip. The counter can be mapped
* RO into a user's address space to achieve low overhead (no system calls),
* high-precision timing.
*
* Note that timer 3 is also used for the high precision profiling timer
* (PROFTIMER code above). Care should be taken when both uses are
* configured as only a token effort is made to avoid conflicting use.
*/
#include "sys/proc.h"
#include "sys/ioctl.h"
#include "sys/malloc.h"
#include "clockioctl.h"
#include "vm/vm_param.h"
#include "vm/vm_pager.h"
#include "vm/vm_prot.h"
#include "sys/specdev.h"
#include "sys/vnode.h"
#include "sys/mman.h"
int clockon = 0; /* non-zero if high-res timer enabled */
#ifdef PROFTIMER
int profprocs = 0; /* # of procs using profiling timer */
#endif
#ifdef DEBUG
int clockdebug = 0;
#endif
/*ARGSUSED*/
clockopen(dev, flags)
dev_t dev;
{
#ifdef PROFTIMER
#ifdef GPROF
/*
* Kernel profiling enabled, give up.
*/
if (profiling)
return(EBUSY);
#endif
/*
* If any user processes are profiling, give up.
*/
if (profprocs)
return(EBUSY);
#endif
if (!clockon) {
startclock();
clockon++;
}
return(0);
}
/*ARGSUSED*/
clockclose(dev, flags)
dev_t dev;
{
(void) clockunmmap(dev, (caddr_t)0);
stopclock();
clockon = 0;
return(0);
}
/*ARGSUSED*/
clockioctl(dev, cmd, data, flag)
dev_t dev;
caddr_t data;
{
int error = 0;
switch (cmd) {
case CLOCKMAP:
error = clockmmap(dev, (caddr_t *)data);
break;
case CLOCKUNMAP:
error = clockunmmap(dev, *(caddr_t *)data);
break;
case CLOCKGETRES:
*(int *)data = CLK_RESOLUTION;
break;
default:
error = EINVAL;
break;
}
return(error);
}
/*ARGSUSED*/
clockmap(dev, off, prot)
dev_t dev;
{
return((off + (IOBASE+CLKBASE+CLKSR-1)) >> PGSHIFT);
}
clockmmap(dev, addrp)
dev_t dev;
caddr_t *addrp;
{
struct proc *p = u.u_procp; /* XXX */
int error;
struct vnode vn;
struct specinfo si;
int flags;
flags = MAP_FILE|MAP_SHARED;
if (*addrp)
flags |= MAP_FIXED;
else
*addrp = (caddr_t)0x1000000; /* XXX */
vn.v_type = VCHR; /* XXX */
vn.v_specinfo = &si; /* XXX */
vn.v_rdev = dev; /* XXX */
error = vm_mmap(u.u_procp->p_map, (vm_offset_t *)addrp,
PAGE_SIZE, VM_PROT_ALL, flags, (caddr_t)&vn, 0);
return(error);
}
clockunmmap(dev, addr)
dev_t dev;
caddr_t addr;
{
struct proc *p = u.u_procp; /* XXX */
int rv;
if (addr == 0)
return(EINVAL); /* XXX: how do we deal with this? */
rv = vm_deallocate(u.u_procp->p_map, (vm_offset_t)addr, PAGE_SIZE);
return(rv == KERN_SUCCESS ? 0 : EINVAL);
}
startclock()
{
register struct clkreg *clk = (struct clkreg *)clkstd[0];
clk->clk_msb2 = -1; clk->clk_lsb2 = -1;
clk->clk_msb3 = -1; clk->clk_lsb3 = -1;
clk->clk_cr2 = CLK_CR3;
clk->clk_cr3 = CLK_OENAB|CLK_8BIT;
clk->clk_cr2 = CLK_CR1;
clk->clk_cr1 = CLK_IENAB;
}
stopclock()
{
register struct clkreg *clk = (struct clkreg *)clkstd[0];
clk->clk_cr2 = CLK_CR3;
clk->clk_cr3 = 0;
clk->clk_cr2 = CLK_CR1;
clk->clk_cr1 = CLK_IENAB;
}
#endif
#ifdef PROFTIMER
/*
* This code allows the hp300 kernel to use one of the extra timers on
* the clock chip for profiling, instead of the regular system timer.
* The advantage of this is that the profiling timer can be turned up to
* a higher interrupt rate, giving finer resolution timing. The profclock
* routine is called from the lev6intr in locore, and is a specialized
* routine that calls addupc. The overhead then is far less than if
* hardclock/softclock was called. Further, the context switch code in
* locore has been changed to turn the profile clock on/off when switching
* into/out of a process that is profiling (startprofclock/stopprofclock).
* This reduces the impact of the profiling clock on other users, and might
* possibly increase the accuracy of the profiling.
*/
int profint = PRF_INTERVAL; /* Clock ticks between interrupts */
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
initprofclock()
{
#if NCLOCK > 0
/*
* If the high-res timer is running, force profiling off.
* Unfortunately, this gets reflected back to the user not as
* an error but as a lack of results.
*/
if (clockon) {
u.u_prof.pr_scale = 0;
return;
}
/*
* Keep track of the number of user processes that are profiling
* by checking the scale value.
*
* XXX: this all assumes that the profiling code is well behaved;
* i.e. profil() is called once per process with pcscale non-zero
* to turn it on, and once with pcscale zero to turn it off.
* Also assumes you don't do any forks or execs. Oh well, there
* is always adb...
*/
if (u.u_prof.pr_scale)
profprocs++;
else
profprocs--;
#endif
/*
* The profile interrupt interval must be an even divisor
* of the CLK_INTERVAL so that scaling from a system clock
* tick to a profile clock tick is possible using integer math.
*/
if (profint > CLK_INTERVAL || (CLK_INTERVAL % profint) != 0)
profint = CLK_INTERVAL;
profscale = CLK_INTERVAL / profint;
}
startprofclock()
{
register struct clkreg *clk = (struct clkreg *)clkstd[0];
clk->clk_msb3 = (profint-1) >> 8 & 0xFF;
clk->clk_lsb3 = (profint-1) & 0xFF;
clk->clk_cr2 = CLK_CR3;
clk->clk_cr3 = CLK_IENAB;
}
stopprofclock()
{
register struct clkreg *clk = (struct clkreg *)clkstd[0];
clk->clk_cr2 = CLK_CR3;
clk->clk_cr3 = 0;
}
#ifdef GPROF
/*
* profclock() is expanded in line in lev6intr() unless profiling kernel.
* Assumes it is called with clock interrupts blocked.
*/
profclock(pc, ps)
caddr_t pc;
int ps;
{
/*
* Came from user mode.
* If this process is being profiled record the tick.
*/
if (USERMODE(ps)) {
if (u.u_prof.pr_scale)
addupc(pc, &u.u_prof, 1);
}
/*
* Came from kernel (supervisor) mode.
* If we are profiling the kernel, record the tick.
*/
else if (profiling < 2) {
register int s = 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
/*
* Initialize the time of day register, based on the time base which is, e.g.
* from a filesystem.
*/
inittodr(base)
time_t base;
{
u_long timbuf = base; /* assume no battery clock exists */
static int bbcinited = 0;
/* XXX */
if (!bbcinited) {
if (badbaddr(&BBCADDR->hil_stat))
printf("WARNING: no battery clock\n");
else
bbcaddr = BBCADDR;
bbcinited = 1;
}
/*
* bbc_to_gmt converts and stores the gmt in timbuf.
* If an error is detected in bbc_to_gmt, or if the filesystem
* time is more recent than the gmt time in the clock,
* then use the filesystem time and warn the user.
*/
if (!bbc_to_gmt(&timbuf) || timbuf < base) {
printf("WARNING: bad date in battery clock\n");
timbuf = base;
}
if (base < 5*SECYR) {
printf("WARNING: preposterous time in file system");
timbuf = 6*SECYR + 186*SECDAY + SECDAY/2;
printf(" -- CHECK AND RESET THE DATE!\n");
}
/* Battery clock does not store usec's, so forget about it. */
time.tv_sec = timbuf;
}
resettodr()
{
register int i;
register struct bbc_tm *tmptr;
tmptr = gmt_to_bbc(time.tv_sec);
decimal_to_bbc(0, 1, tmptr->tm_sec);
decimal_to_bbc(2, 3, tmptr->tm_min);
decimal_to_bbc(4, 5, tmptr->tm_hour);
decimal_to_bbc(7, 8, tmptr->tm_mday);
decimal_to_bbc(9, 10, tmptr->tm_mon);
decimal_to_bbc(11, 12, tmptr->tm_year);
/* Some bogusness to deal with seemingly broken hardware. Nonsense */
bbc_registers[5] = ((tmptr->tm_hour / 10) & 0x03) + 8;
write_bbc_reg(15, 13); /* reset prescalar */
for (i = 0; i <= NUM_BBC_REGS; i++)
if (bbc_registers[i] != write_bbc_reg(i, bbc_registers[i])) {
printf("Cannot set battery backed clock\n");
break;
}
}
struct bbc_tm *
gmt_to_bbc(tim)
long tim;
{
register int i;
register long hms, day;
static struct bbc_tm rt;
day = tim / SECDAY;
hms = tim % SECDAY;
/* Hours, minutes, seconds are easy */
rt.tm_hour = hms / 3600;
rt.tm_min = (hms % 3600) / 60;
rt.tm_sec = (hms % 3600) % 60;
/* Number of years in days */
for (i = STARTOFTIME - 1900; day >= days_in_year(i); i++)
day -= days_in_year(i);
rt.tm_year = i;
/* Number of months in days left */
if (leapyear(rt.tm_year))
days_in_month(FEBRUARY) = 29;
for (i = 1; day >= days_in_month(i); i++)
day -= days_in_month(i);
days_in_month(FEBRUARY) = 28;
rt.tm_mon = i;
/* Days are what is left over (+1) from all that. */
rt.tm_mday = day + 1;
return(&rt);
}
bbc_to_gmt(timbuf)
u_long *timbuf;
{
register int i;
register u_long tmp;
int year, month, day, hour, min, sec;
read_bbc();
sec = bbc_to_decimal(1, 0);
min = bbc_to_decimal(3, 2);
/*
* Hours are different for some reason. Makes no sense really.
*/
hour = ((bbc_registers[5] & 0x03) * 10) + bbc_registers[4];
day = bbc_to_decimal(8, 7);
month = bbc_to_decimal(10, 9);
year = bbc_to_decimal(12, 11) + 1900;
range_test(hour, 0, 23);
range_test(day, 1, 31);
range_test(month, 1, 12);
range_test(year, STARTOFTIME, 2000);
tmp = 0;
for (i = STARTOFTIME; i < year; i++)
tmp += days_in_year(i);
if (leapyear(year) && month > FEBRUARY)
tmp++;
for (i = 1; i < month; i++)
tmp += days_in_month(i);
tmp += (day - 1);
tmp = ((tmp * 24 + hour) * 60 + min) * 60 + sec;
*timbuf = tmp;
return(1);
}
read_bbc()
{
register int i, read_okay;
read_okay = 0;
while (!read_okay) {
read_okay = 1;
for (i = 0; i <= NUM_BBC_REGS; i++)
bbc_registers[i] = read_bbc_reg(i);
for (i = 0; i <= NUM_BBC_REGS; i++)
if (bbc_registers[i] != read_bbc_reg(i))
read_okay = 0;
}
}
u_char
read_bbc_reg(reg)
int reg;
{
u_char data = reg;
if (bbcaddr) {
send_hil_cmd(bbcaddr, BBC_SET_REG, &data, 1, NULL);
send_hil_cmd(bbcaddr, BBC_READ_REG, NULL, 0, &data);
}
return(data);
}
u_char
write_bbc_reg(reg, data)
u_int data;
{
u_char tmp;
tmp = (u_char) ((data << HIL_SSHIFT) | reg);
if (bbcaddr) {
send_hil_cmd(bbcaddr, BBC_SET_REG, &tmp, 1, NULL);
send_hil_cmd(bbcaddr, BBC_WRITE_REG, NULL, 0, NULL);
send_hil_cmd(bbcaddr, BBC_READ_REG, NULL, 0, &tmp);
}
return(tmp);
}
Continuous source code history from original PDP-7 UNIX to FreeBSD 2, the first fully unencumbered FreeBSD release.