67e2a29216
just once around the whole group of accesses.
429 lines
11 KiB
C
429 lines
11 KiB
C
/*-
|
|
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
|
|
*
|
|
* Copyright (c) 2008 Poul-Henning Kamp
|
|
* Copyright (c) 2010 Alexander Motin <mav@FreeBSD.org>
|
|
* 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.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
|
|
*
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include "opt_isa.h"
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/bus.h>
|
|
#include <sys/clock.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/mutex.h>
|
|
#include <sys/kdb.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/module.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/rman.h>
|
|
#include <sys/timeet.h>
|
|
|
|
#include <isa/rtc.h>
|
|
#ifdef DEV_ISA
|
|
#include <isa/isareg.h>
|
|
#include <isa/isavar.h>
|
|
#endif
|
|
#include <machine/intr_machdep.h>
|
|
#include "clock_if.h"
|
|
|
|
/*
|
|
* atrtc_lock protects low-level access to individual hardware registers.
|
|
* atrtc_time_lock protects the entire sequence of accessing multiple registers
|
|
* to read or write the date and time.
|
|
*/
|
|
static struct mtx atrtc_lock;
|
|
MTX_SYSINIT(atrtc_lock_init, &atrtc_lock, "atrtc", MTX_SPIN | MTX_NOPROFILE);
|
|
|
|
struct mtx atrtc_time_lock;
|
|
MTX_SYSINIT(atrtc_time_lock_init, &atrtc_time_lock, "atrtc", MTX_DEF);
|
|
|
|
int atrtcclock_disable = 0;
|
|
|
|
static int rtc_reg = -1;
|
|
static u_char rtc_statusa = RTCSA_DIVIDER | RTCSA_NOPROF;
|
|
static u_char rtc_statusb = RTCSB_24HR;
|
|
|
|
/*
|
|
* RTC support routines
|
|
*/
|
|
|
|
static inline u_char
|
|
rtcin_locked(int reg)
|
|
{
|
|
|
|
if (rtc_reg != reg) {
|
|
inb(0x84);
|
|
outb(IO_RTC, reg);
|
|
rtc_reg = reg;
|
|
inb(0x84);
|
|
}
|
|
return (inb(IO_RTC + 1));
|
|
}
|
|
|
|
static inline void
|
|
rtcout_locked(int reg, u_char val)
|
|
{
|
|
|
|
if (rtc_reg != reg) {
|
|
inb(0x84);
|
|
outb(IO_RTC, reg);
|
|
rtc_reg = reg;
|
|
inb(0x84);
|
|
}
|
|
outb(IO_RTC + 1, val);
|
|
inb(0x84);
|
|
}
|
|
|
|
int
|
|
rtcin(int reg)
|
|
{
|
|
u_char val;
|
|
|
|
mtx_lock_spin(&atrtc_lock);
|
|
val = rtcin_locked(reg);
|
|
mtx_unlock_spin(&atrtc_lock);
|
|
return (val);
|
|
}
|
|
|
|
void
|
|
writertc(int reg, u_char val)
|
|
{
|
|
|
|
mtx_lock_spin(&atrtc_lock);
|
|
rtcout_locked(reg, val);
|
|
mtx_unlock_spin(&atrtc_lock);
|
|
}
|
|
|
|
static void
|
|
atrtc_start(void)
|
|
{
|
|
|
|
mtx_lock_spin(&atrtc_lock);
|
|
rtcout_locked(RTC_STATUSA, rtc_statusa);
|
|
rtcout_locked(RTC_STATUSB, RTCSB_24HR);
|
|
mtx_unlock_spin(&atrtc_lock);
|
|
}
|
|
|
|
static void
|
|
atrtc_rate(unsigned rate)
|
|
{
|
|
|
|
rtc_statusa = RTCSA_DIVIDER | rate;
|
|
writertc(RTC_STATUSA, rtc_statusa);
|
|
}
|
|
|
|
static void
|
|
atrtc_enable_intr(void)
|
|
{
|
|
|
|
rtc_statusb |= RTCSB_PINTR;
|
|
mtx_lock_spin(&atrtc_lock);
|
|
rtcout_locked(RTC_STATUSB, rtc_statusb);
|
|
rtcin_locked(RTC_INTR);
|
|
mtx_unlock_spin(&atrtc_lock);
|
|
}
|
|
|
|
static void
|
|
atrtc_disable_intr(void)
|
|
{
|
|
|
|
rtc_statusb &= ~RTCSB_PINTR;
|
|
mtx_lock_spin(&atrtc_lock);
|
|
rtcout_locked(RTC_STATUSB, rtc_statusb);
|
|
rtcin_locked(RTC_INTR);
|
|
mtx_unlock_spin(&atrtc_lock);
|
|
}
|
|
|
|
void
|
|
atrtc_restore(void)
|
|
{
|
|
|
|
/* Restore all of the RTC's "status" (actually, control) registers. */
|
|
mtx_lock_spin(&atrtc_lock);
|
|
rtcin_locked(RTC_STATUSA); /* dummy to get rtc_reg set */
|
|
rtcout_locked(RTC_STATUSB, RTCSB_24HR);
|
|
rtcout_locked(RTC_STATUSA, rtc_statusa);
|
|
rtcout_locked(RTC_STATUSB, rtc_statusb);
|
|
rtcin_locked(RTC_INTR);
|
|
mtx_unlock_spin(&atrtc_lock);
|
|
}
|
|
|
|
/**********************************************************************
|
|
* RTC driver for subr_rtc
|
|
*/
|
|
|
|
struct atrtc_softc {
|
|
int port_rid, intr_rid;
|
|
struct resource *port_res;
|
|
struct resource *intr_res;
|
|
void *intr_handler;
|
|
struct eventtimer et;
|
|
};
|
|
|
|
static int
|
|
rtc_start(struct eventtimer *et, sbintime_t first, sbintime_t period)
|
|
{
|
|
|
|
atrtc_rate(max(fls(period + (period >> 1)) - 17, 1));
|
|
atrtc_enable_intr();
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
rtc_stop(struct eventtimer *et)
|
|
{
|
|
|
|
atrtc_disable_intr();
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* This routine receives statistical clock interrupts from the RTC.
|
|
* As explained above, these occur at 128 interrupts per second.
|
|
* When profiling, we receive interrupts at a rate of 1024 Hz.
|
|
*
|
|
* This does not actually add as much overhead as it sounds, because
|
|
* when the statistical clock is active, the hardclock driver no longer
|
|
* needs to keep (inaccurate) statistics on its own. This decouples
|
|
* statistics gathering from scheduling interrupts.
|
|
*
|
|
* The RTC chip requires that we read status register C (RTC_INTR)
|
|
* to acknowledge an interrupt, before it will generate the next one.
|
|
* Under high interrupt load, rtcintr() can be indefinitely delayed and
|
|
* the clock can tick immediately after the read from RTC_INTR. In this
|
|
* case, the mc146818A interrupt signal will not drop for long enough
|
|
* to register with the 8259 PIC. If an interrupt is missed, the stat
|
|
* clock will halt, considerably degrading system performance. This is
|
|
* why we use 'while' rather than a more straightforward 'if' below.
|
|
* Stat clock ticks can still be lost, causing minor loss of accuracy
|
|
* in the statistics, but the stat clock will no longer stop.
|
|
*/
|
|
static int
|
|
rtc_intr(void *arg)
|
|
{
|
|
struct atrtc_softc *sc = (struct atrtc_softc *)arg;
|
|
int flag = 0;
|
|
|
|
while (rtcin(RTC_INTR) & RTCIR_PERIOD) {
|
|
flag = 1;
|
|
if (sc->et.et_active)
|
|
sc->et.et_event_cb(&sc->et, sc->et.et_arg);
|
|
}
|
|
return(flag ? FILTER_HANDLED : FILTER_STRAY);
|
|
}
|
|
|
|
/*
|
|
* Attach to the ISA PnP descriptors for the timer and realtime clock.
|
|
*/
|
|
static struct isa_pnp_id atrtc_ids[] = {
|
|
{ 0x000bd041 /* PNP0B00 */, "AT realtime clock" },
|
|
{ 0 }
|
|
};
|
|
|
|
static int
|
|
atrtc_probe(device_t dev)
|
|
{
|
|
int result;
|
|
|
|
result = ISA_PNP_PROBE(device_get_parent(dev), dev, atrtc_ids);
|
|
/* ENOENT means no PnP-ID, device is hinted. */
|
|
if (result == ENOENT) {
|
|
device_set_desc(dev, "AT realtime clock");
|
|
return (BUS_PROBE_LOW_PRIORITY);
|
|
}
|
|
return (result);
|
|
}
|
|
|
|
static int
|
|
atrtc_attach(device_t dev)
|
|
{
|
|
struct atrtc_softc *sc;
|
|
rman_res_t s;
|
|
int i;
|
|
|
|
sc = device_get_softc(dev);
|
|
sc->port_res = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->port_rid,
|
|
IO_RTC, IO_RTC + 1, 2, RF_ACTIVE);
|
|
if (sc->port_res == NULL)
|
|
device_printf(dev, "Warning: Couldn't map I/O.\n");
|
|
atrtc_start();
|
|
clock_register(dev, 1000000);
|
|
bzero(&sc->et, sizeof(struct eventtimer));
|
|
if (!atrtcclock_disable &&
|
|
(resource_int_value(device_get_name(dev), device_get_unit(dev),
|
|
"clock", &i) != 0 || i != 0)) {
|
|
sc->intr_rid = 0;
|
|
while (bus_get_resource(dev, SYS_RES_IRQ, sc->intr_rid,
|
|
&s, NULL) == 0 && s != 8)
|
|
sc->intr_rid++;
|
|
sc->intr_res = bus_alloc_resource(dev, SYS_RES_IRQ,
|
|
&sc->intr_rid, 8, 8, 1, RF_ACTIVE);
|
|
if (sc->intr_res == NULL) {
|
|
device_printf(dev, "Can't map interrupt.\n");
|
|
return (0);
|
|
} else if ((bus_setup_intr(dev, sc->intr_res, INTR_TYPE_CLK,
|
|
rtc_intr, NULL, sc, &sc->intr_handler))) {
|
|
device_printf(dev, "Can't setup interrupt.\n");
|
|
return (0);
|
|
} else {
|
|
/* Bind IRQ to BSP to avoid live migration. */
|
|
bus_bind_intr(dev, sc->intr_res, 0);
|
|
}
|
|
sc->et.et_name = "RTC";
|
|
sc->et.et_flags = ET_FLAGS_PERIODIC | ET_FLAGS_POW2DIV;
|
|
sc->et.et_quality = 0;
|
|
sc->et.et_frequency = 32768;
|
|
sc->et.et_min_period = 0x00080000;
|
|
sc->et.et_max_period = 0x80000000;
|
|
sc->et.et_start = rtc_start;
|
|
sc->et.et_stop = rtc_stop;
|
|
sc->et.et_priv = dev;
|
|
et_register(&sc->et);
|
|
}
|
|
return(0);
|
|
}
|
|
|
|
static int
|
|
atrtc_resume(device_t dev)
|
|
{
|
|
|
|
atrtc_restore();
|
|
return(0);
|
|
}
|
|
|
|
static int
|
|
atrtc_settime(device_t dev __unused, struct timespec *ts)
|
|
{
|
|
struct bcd_clocktime bct;
|
|
|
|
clock_ts_to_bcd(ts, &bct, false);
|
|
clock_dbgprint_bcd(dev, CLOCK_DBG_WRITE, &bct);
|
|
|
|
mtx_lock(&atrtc_time_lock);
|
|
mtx_lock_spin(&atrtc_lock);
|
|
|
|
/* Disable RTC updates and interrupts. */
|
|
rtcout_locked(RTC_STATUSB, RTCSB_HALT | RTCSB_24HR);
|
|
|
|
/* Write all the time registers. */
|
|
rtcout_locked(RTC_SEC, bct.sec);
|
|
rtcout_locked(RTC_MIN, bct.min);
|
|
rtcout_locked(RTC_HRS, bct.hour);
|
|
rtcout_locked(RTC_WDAY, bct.dow + 1);
|
|
rtcout_locked(RTC_DAY, bct.day);
|
|
rtcout_locked(RTC_MONTH, bct.mon);
|
|
rtcout_locked(RTC_YEAR, bct.year & 0xff);
|
|
#ifdef USE_RTC_CENTURY
|
|
rtcout_locked(RTC_CENTURY, bct.year >> 8);
|
|
#endif
|
|
|
|
/*
|
|
* Re-enable RTC updates and interrupts.
|
|
*/
|
|
rtcout_locked(RTC_STATUSB, rtc_statusb);
|
|
rtcin_locked(RTC_INTR);
|
|
|
|
mtx_unlock_spin(&atrtc_lock);
|
|
mtx_unlock(&atrtc_time_lock);
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
atrtc_gettime(device_t dev, struct timespec *ts)
|
|
{
|
|
struct bcd_clocktime bct;
|
|
|
|
/* Look if we have a RTC present and the time is valid */
|
|
if (!(rtcin(RTC_STATUSD) & RTCSD_PWR)) {
|
|
device_printf(dev, "WARNING: Battery failure indication\n");
|
|
return (EINVAL);
|
|
}
|
|
|
|
/*
|
|
* wait for time update to complete
|
|
* If RTCSA_TUP is zero, we have at least 244us before next update.
|
|
* This is fast enough on most hardware, but a refinement would be
|
|
* to make sure that no more than 240us pass after we start reading,
|
|
* and try again if so.
|
|
*/
|
|
mtx_lock(&atrtc_time_lock);
|
|
while (rtcin(RTC_STATUSA) & RTCSA_TUP)
|
|
continue;
|
|
mtx_lock_spin(&atrtc_lock);
|
|
bct.sec = rtcin_locked(RTC_SEC);
|
|
bct.min = rtcin_locked(RTC_MIN);
|
|
bct.hour = rtcin_locked(RTC_HRS);
|
|
bct.day = rtcin_locked(RTC_DAY);
|
|
bct.mon = rtcin_locked(RTC_MONTH);
|
|
bct.year = rtcin_locked(RTC_YEAR);
|
|
#ifdef USE_RTC_CENTURY
|
|
bct.year |= rtcin_locked(RTC_CENTURY) << 8;
|
|
#endif
|
|
mtx_unlock_spin(&atrtc_lock);
|
|
mtx_unlock(&atrtc_time_lock);
|
|
/* dow is unused in timespec conversion and we have no nsec info. */
|
|
bct.dow = 0;
|
|
bct.nsec = 0;
|
|
clock_dbgprint_bcd(dev, CLOCK_DBG_READ, &bct);
|
|
return (clock_bcd_to_ts(&bct, ts, false));
|
|
}
|
|
|
|
static device_method_t atrtc_methods[] = {
|
|
/* Device interface */
|
|
DEVMETHOD(device_probe, atrtc_probe),
|
|
DEVMETHOD(device_attach, atrtc_attach),
|
|
DEVMETHOD(device_detach, bus_generic_detach),
|
|
DEVMETHOD(device_shutdown, bus_generic_shutdown),
|
|
DEVMETHOD(device_suspend, bus_generic_suspend),
|
|
/* XXX stop statclock? */
|
|
DEVMETHOD(device_resume, atrtc_resume),
|
|
|
|
/* clock interface */
|
|
DEVMETHOD(clock_gettime, atrtc_gettime),
|
|
DEVMETHOD(clock_settime, atrtc_settime),
|
|
|
|
{ 0, 0 }
|
|
};
|
|
|
|
static driver_t atrtc_driver = {
|
|
"atrtc",
|
|
atrtc_methods,
|
|
sizeof(struct atrtc_softc),
|
|
};
|
|
|
|
static devclass_t atrtc_devclass;
|
|
|
|
DRIVER_MODULE(atrtc, isa, atrtc_driver, atrtc_devclass, 0, 0);
|
|
DRIVER_MODULE(atrtc, acpi, atrtc_driver, atrtc_devclass, 0, 0);
|
|
ISA_PNP_INFO(atrtc_ids);
|