freebsd-dev/sys/dev/acpica/acpi_timer.c
David Malone 041b706b2f Despite several examples in the kernel, the third argument of
sysctl_handle_int is not sizeof the int type you want to export.
The type must always be an int or an unsigned int.

Remove the instances where a sizeof(variable) is passed to stop
people accidently cut and pasting these examples.

In a few places this was sysctl_handle_int was being used on 64 bit
types, which would truncate the value to be exported.  In these
cases use sysctl_handle_quad to export them and change the format
to Q so that sysctl(1) can still print them.
2007-06-04 18:25:08 +00:00

369 lines
10 KiB
C

/*-
* Copyright (c) 2000, 2001 Michael Smith
* Copyright (c) 2000 BSDi
* 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_acpi.h"
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/sysctl.h>
#include <sys/timetc.h>
#include <machine/bus.h>
#include <machine/resource.h>
#include <sys/rman.h>
#include <contrib/dev/acpica/acpi.h>
#include <dev/acpica/acpivar.h>
#include <dev/pci/pcivar.h>
/*
* A timecounter based on the free-running ACPI timer.
*
* Based on the i386-only mp_clock.c by <phk@FreeBSD.ORG>.
*/
/* Hooks for the ACPI CA debugging infrastructure */
#define _COMPONENT ACPI_TIMER
ACPI_MODULE_NAME("TIMER")
static device_t acpi_timer_dev;
static struct resource *acpi_timer_reg;
static bus_space_handle_t acpi_timer_bsh;
static bus_space_tag_t acpi_timer_bst;
static u_int acpi_timer_frequency = 14318182 / 4;
static void acpi_timer_identify(driver_t *driver, device_t parent);
static int acpi_timer_probe(device_t dev);
static int acpi_timer_attach(device_t dev);
static u_int acpi_timer_get_timecount(struct timecounter *tc);
static u_int acpi_timer_get_timecount_safe(struct timecounter *tc);
static int acpi_timer_sysctl_freq(SYSCTL_HANDLER_ARGS);
static void acpi_timer_boot_test(void);
static u_int acpi_timer_read(void);
static int acpi_timer_test(void);
static device_method_t acpi_timer_methods[] = {
DEVMETHOD(device_identify, acpi_timer_identify),
DEVMETHOD(device_probe, acpi_timer_probe),
DEVMETHOD(device_attach, acpi_timer_attach),
{0, 0}
};
static driver_t acpi_timer_driver = {
"acpi_timer",
acpi_timer_methods,
0,
};
static devclass_t acpi_timer_devclass;
DRIVER_MODULE(acpi_timer, acpi, acpi_timer_driver, acpi_timer_devclass, 0, 0);
MODULE_DEPEND(acpi_timer, acpi, 1, 1, 1);
static struct timecounter acpi_timer_timecounter = {
acpi_timer_get_timecount_safe, /* get_timecount function */
0, /* no poll_pps */
0, /* no default counter_mask */
0, /* no default frequency */
"ACPI", /* name */
1000 /* quality */
};
static u_int
acpi_timer_read()
{
return (bus_space_read_4(acpi_timer_bst, acpi_timer_bsh, 0));
}
/*
* Locate the ACPI timer using the FADT, set up and allocate the I/O resources
* we will be using.
*/
static void
acpi_timer_identify(driver_t *driver, device_t parent)
{
device_t dev;
u_long rlen, rstart;
int rid, rtype;
ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
if (acpi_disabled("timer") || (acpi_quirks & ACPI_Q_TIMER) ||
acpi_timer_dev)
return_VOID;
if ((dev = BUS_ADD_CHILD(parent, 0, "acpi_timer", 0)) == NULL) {
device_printf(parent, "could not add acpi_timer0\n");
return_VOID;
}
acpi_timer_dev = dev;
rid = 0;
rtype = AcpiGbl_FADT.XPmTimerBlock.SpaceId ?
SYS_RES_IOPORT : SYS_RES_MEMORY;
rlen = AcpiGbl_FADT.PmTimerLength;
rstart = AcpiGbl_FADT.XPmTimerBlock.Address;
if (bus_set_resource(dev, rtype, rid, rstart, rlen))
device_printf(dev, "couldn't set resource (%s 0x%lx+0x%lx)\n",
(rtype == SYS_RES_IOPORT) ? "port" : "mem", rstart, rlen);
return_VOID;
}
static int
acpi_timer_probe(device_t dev)
{
char desc[40];
int i, j, rid, rtype;
ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
if (dev != acpi_timer_dev)
return (ENXIO);
rid = 0;
rtype = AcpiGbl_FADT.XPmTimerBlock.SpaceId ?
SYS_RES_IOPORT : SYS_RES_MEMORY;
acpi_timer_reg = bus_alloc_resource_any(dev, rtype, &rid, RF_ACTIVE);
if (acpi_timer_reg == NULL) {
device_printf(dev, "couldn't allocate resource (%s 0x%lx)\n",
(rtype == SYS_RES_IOPORT) ? "port" : "mem",
(u_long)AcpiGbl_FADT.XPmTimerBlock.Address);
return (ENXIO);
}
acpi_timer_bsh = rman_get_bushandle(acpi_timer_reg);
acpi_timer_bst = rman_get_bustag(acpi_timer_reg);
if (AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER)
acpi_timer_timecounter.tc_counter_mask = 0xffffffff;
else
acpi_timer_timecounter.tc_counter_mask = 0x00ffffff;
acpi_timer_timecounter.tc_frequency = acpi_timer_frequency;
if (testenv("debug.acpi.timer_test"))
acpi_timer_boot_test();
/*
* If all tests of the counter succeed, use the ACPI-fast method. If
* at least one failed, default to using the safe routine, which reads
* the timer multiple times to get a consistent value before returning.
*/
j = 0;
if (bootverbose)
printf("ACPI timer:");
for (i = 0; i < 10; i++)
j += acpi_timer_test();
if (bootverbose)
printf(" -> %d\n", j);
if (j == 10) {
acpi_timer_timecounter.tc_name = "ACPI-fast";
acpi_timer_timecounter.tc_get_timecount = acpi_timer_get_timecount;
} else {
acpi_timer_timecounter.tc_name = "ACPI-safe";
acpi_timer_timecounter.tc_get_timecount = acpi_timer_get_timecount_safe;
}
tc_init(&acpi_timer_timecounter);
sprintf(desc, "%d-bit timer at 3.579545MHz",
(AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER) ? 32 : 24);
device_set_desc_copy(dev, desc);
/* Release the resource, we'll allocate it again during attach. */
bus_release_resource(dev, rtype, rid, acpi_timer_reg);
return (0);
}
static int
acpi_timer_attach(device_t dev)
{
int rid, rtype;
ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
rid = 0;
rtype = AcpiGbl_FADT.XPmTimerBlock.SpaceId ?
SYS_RES_IOPORT : SYS_RES_MEMORY;
acpi_timer_reg = bus_alloc_resource_any(dev, rtype, &rid, RF_ACTIVE);
if (acpi_timer_reg == NULL)
return (ENXIO);
acpi_timer_bsh = rman_get_bushandle(acpi_timer_reg);
acpi_timer_bst = rman_get_bustag(acpi_timer_reg);
return (0);
}
/*
* Fetch current time value from reliable hardware.
*/
static u_int
acpi_timer_get_timecount(struct timecounter *tc)
{
return (acpi_timer_read());
}
/*
* Fetch current time value from hardware that may not correctly
* latch the counter. We need to read until we have three monotonic
* samples and then use the middle one, otherwise we are not protected
* against the fact that the bits can be wrong in two directions. If
* we only cared about monosity, two reads would be enough.
*/
static u_int
acpi_timer_get_timecount_safe(struct timecounter *tc)
{
u_int u1, u2, u3;
u2 = acpi_timer_read();
u3 = acpi_timer_read();
do {
u1 = u2;
u2 = u3;
u3 = acpi_timer_read();
} while (u1 > u2 || u2 > u3);
return (u2);
}
/*
* Timecounter freqency adjustment interface.
*/
static int
acpi_timer_sysctl_freq(SYSCTL_HANDLER_ARGS)
{
int error;
u_int freq;
if (acpi_timer_timecounter.tc_frequency == 0)
return (EOPNOTSUPP);
freq = acpi_timer_frequency;
error = sysctl_handle_int(oidp, &freq, 0, req);
if (error == 0 && req->newptr != NULL) {
acpi_timer_frequency = freq;
acpi_timer_timecounter.tc_frequency = acpi_timer_frequency;
}
return (error);
}
SYSCTL_PROC(_machdep, OID_AUTO, acpi_timer_freq, CTLTYPE_INT | CTLFLAG_RW,
0, sizeof(u_int), acpi_timer_sysctl_freq, "I", "");
/*
* Some ACPI timers are known or believed to suffer from implementation
* problems which can lead to erroneous values being read. This function
* tests for consistent results from the timer and returns 1 if it believes
* the timer is consistent, otherwise it returns 0.
*
* It appears the cause is that the counter is not latched to the PCI bus
* clock when read:
*
* ] 20. ACPI Timer Errata
* ]
* ] Problem: The power management timer may return improper result when
* ] read. Although the timer value settles properly after incrementing,
* ] while incrementing there is a 3nS window every 69.8nS where the
* ] timer value is indeterminate (a 4.2% chance that the data will be
* ] incorrect when read). As a result, the ACPI free running count up
* ] timer specification is violated due to erroneous reads. Implication:
* ] System hangs due to the "inaccuracy" of the timer when used by
* ] software for time critical events and delays.
* ]
* ] Workaround: Read the register twice and compare.
* ] Status: This will not be fixed in the PIIX4 or PIIX4E, it is fixed
* ] in the PIIX4M.
*/
#define N 2000
static int
acpi_timer_test()
{
uint32_t last, this;
int min, max, n, delta;
register_t s;
min = 10000000;
max = 0;
/* Test the timer with interrupts disabled to get accurate results. */
s = intr_disable();
last = acpi_timer_read();
for (n = 0; n < N; n++) {
this = acpi_timer_read();
delta = acpi_TimerDelta(this, last);
if (delta > max)
max = delta;
else if (delta < min)
min = delta;
last = this;
}
intr_restore(s);
if (max - min > 2)
n = 0;
else if (min < 0 || max == 0)
n = 0;
else
n = 1;
if (bootverbose)
printf(" %d/%d", n, max-min);
return (n);
}
#undef N
/*
* Test harness for verifying ACPI timer behaviour.
* Boot with debug.acpi.timer_test set to invoke this.
*/
static void
acpi_timer_boot_test(void)
{
uint32_t u1, u2, u3;
u1 = acpi_timer_read();
u2 = acpi_timer_read();
u3 = acpi_timer_read();
device_printf(acpi_timer_dev, "timer test in progress, reboot to quit.\n");
for (;;) {
/*
* The failure case is where u3 > u1, but u2 does not fall between
* the two, ie. it contains garbage.
*/
if (u3 > u1) {
if (u2 < u1 || u2 > u3)
device_printf(acpi_timer_dev,
"timer is not monotonic: 0x%08x,0x%08x,0x%08x\n",
u1, u2, u3);
}
u1 = u2;
u2 = u3;
u3 = acpi_timer_read();
}
}