freebsd-skq/sys/dev/acpica/acpi_hpet.c
avg c3b9dff1e4 acpi_hpet: correctly get number of timers/comparators in a timer block
Also, account for a quirk of AMD/ATI HPET which reports number of timers
instead of id of the last timer as manadated by the specification.
Currently this has no effect on functionality but in the future we may
make actual use of the HPET timers, not only of its timecounter.

MFC after:	2 weeks
2010-01-27 10:17:28 +00:00

331 lines
8.4 KiB
C

/*-
* Copyright (c) 2005 Poul-Henning Kamp
* 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/rman.h>
#include <sys/time.h>
#include <sys/timetc.h>
#include <contrib/dev/acpica/include/acpi.h>
#include <contrib/dev/acpica/include/accommon.h>
#include <dev/acpica/acpivar.h>
#include <dev/acpica/acpi_hpet.h>
#define HPET_VENDID_AMD 0x4353
#define HPET_VENDID_INTEL 0x8086
ACPI_SERIAL_DECL(hpet, "ACPI HPET support");
static devclass_t acpi_hpet_devclass;
/* ACPI CA debugging */
#define _COMPONENT ACPI_TIMER
ACPI_MODULE_NAME("HPET")
struct acpi_hpet_softc {
device_t dev;
struct resource *mem_res;
ACPI_HANDLE handle;
};
static u_int hpet_get_timecount(struct timecounter *tc);
static void acpi_hpet_test(struct acpi_hpet_softc *sc);
static char *hpet_ids[] = { "PNP0103", NULL };
struct timecounter hpet_timecounter = {
.tc_get_timecount = hpet_get_timecount,
.tc_counter_mask = ~0u,
.tc_name = "HPET",
.tc_quality = 900,
};
static u_int
hpet_get_timecount(struct timecounter *tc)
{
struct acpi_hpet_softc *sc;
sc = tc->tc_priv;
return (bus_read_4(sc->mem_res, HPET_MAIN_COUNTER));
}
static void
hpet_enable(struct acpi_hpet_softc *sc)
{
uint32_t val;
val = bus_read_4(sc->mem_res, HPET_CONFIG);
val &= ~HPET_CNF_LEG_RT;
val |= HPET_CNF_ENABLE;
bus_write_4(sc->mem_res, HPET_CONFIG, val);
}
static void
hpet_disable(struct acpi_hpet_softc *sc)
{
uint32_t val;
val = bus_read_4(sc->mem_res, HPET_CONFIG);
val &= ~HPET_CNF_ENABLE;
bus_write_4(sc->mem_res, HPET_CONFIG, val);
}
/* Discover the HPET via the ACPI table of the same name. */
static void
acpi_hpet_identify(driver_t *driver, device_t parent)
{
ACPI_TABLE_HPET *hpet;
ACPI_TABLE_HEADER *hdr;
ACPI_STATUS status;
device_t child;
/* Only one HPET device can be added. */
if (devclass_get_device(acpi_hpet_devclass, 0))
return;
/* Currently, ID and minimum clock tick info is unused. */
status = AcpiGetTable(ACPI_SIG_HPET, 1, (ACPI_TABLE_HEADER **)&hdr);
if (ACPI_FAILURE(status))
return;
/*
* The unit number could be derived from hdr->Sequence but we only
* support one HPET device.
*/
hpet = (ACPI_TABLE_HPET *)hdr;
if (hpet->Sequence != 0)
printf("ACPI HPET table warning: Sequence is non-zero (%d)\n",
hpet->Sequence);
child = BUS_ADD_CHILD(parent, ACPI_DEV_BASE_ORDER, "acpi_hpet", 0);
if (child == NULL) {
printf("%s: can't add child\n", __func__);
return;
}
bus_set_resource(child, SYS_RES_MEMORY, 0, hpet->Address.Address,
HPET_MEM_WIDTH);
}
static int
acpi_hpet_probe(device_t dev)
{
ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
if (acpi_disabled("hpet"))
return (ENXIO);
if (acpi_get_handle(dev) != NULL &&
(ACPI_ID_PROBE(device_get_parent(dev), dev, hpet_ids) == NULL ||
device_get_unit(dev) != 0))
return (ENXIO);
device_set_desc(dev, "High Precision Event Timer");
return (0);
}
static int
acpi_hpet_attach(device_t dev)
{
struct acpi_hpet_softc *sc;
int rid, num_timers;
uint32_t val, val2;
uintmax_t freq;
uint16_t vendor;
ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
sc = device_get_softc(dev);
sc->dev = dev;
sc->handle = acpi_get_handle(dev);
rid = 0;
sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
RF_ACTIVE);
if (sc->mem_res == NULL)
return (ENOMEM);
/* Validate that we can access the whole region. */
if (rman_get_size(sc->mem_res) < HPET_MEM_WIDTH) {
device_printf(dev, "memory region width %ld too small\n",
rman_get_size(sc->mem_res));
bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res);
return (ENXIO);
}
/* Be sure timer is enabled. */
hpet_enable(sc);
/* Read basic statistics about the timer. */
val = bus_read_4(sc->mem_res, HPET_PERIOD);
if (val == 0) {
device_printf(dev, "invalid period\n");
hpet_disable(sc);
bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res);
return (ENXIO);
}
freq = (1000000000000000LL + val / 2) / val;
if (bootverbose) {
val = bus_read_4(sc->mem_res, HPET_CAPABILITIES);
/*
* ATI/AMD violates IA-PC HPET (High Precision Event Timers)
* Specification and provides an off by one number
* of timers/comparators.
* Additionally, they use unregistered value in VENDOR_ID field.
*/
num_timers = 1 + ((val & HPET_CAP_NUM_TIM) >> 8);
vendor = val >> 16;
if (vendor == HPET_VENDID_AMD && num_timers > 0)
num_timers--;
device_printf(dev,
"vend: 0x%x rev: 0x%x num: %d hz: %jd opts:%s%s\n",
vendor, val & HPET_CAP_REV_ID,
num_timers, freq,
(val & HPET_CAP_LEG_RT) ? " legacy_route" : "",
(val & HPET_CAP_COUNT_SIZE) ? " 64-bit" : "");
}
if (testenv("debug.acpi.hpet_test"))
acpi_hpet_test(sc);
/*
* Don't attach if the timer never increments. Since the spec
* requires it to be at least 10 MHz, it has to change in 1 us.
*/
val = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
DELAY(1);
val2 = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
if (val == val2) {
device_printf(dev, "HPET never increments, disabling\n");
hpet_disable(sc);
bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res);
return (ENXIO);
}
hpet_timecounter.tc_frequency = freq;
hpet_timecounter.tc_priv = sc;
tc_init(&hpet_timecounter);
return (0);
}
static int
acpi_hpet_detach(device_t dev)
{
ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
/* XXX Without a tc_remove() function, we can't detach. */
return (EBUSY);
}
static int
acpi_hpet_suspend(device_t dev)
{
struct acpi_hpet_softc *sc;
/*
* Disable the timer during suspend. The timer will not lose
* its state in S1 or S2, but we are required to disable
* it.
*/
sc = device_get_softc(dev);
hpet_disable(sc);
return (0);
}
static int
acpi_hpet_resume(device_t dev)
{
struct acpi_hpet_softc *sc;
/* Re-enable the timer after a resume to keep the clock advancing. */
sc = device_get_softc(dev);
hpet_enable(sc);
return (0);
}
/* Print some basic latency/rate information to assist in debugging. */
static void
acpi_hpet_test(struct acpi_hpet_softc *sc)
{
int i;
uint32_t u1, u2;
struct bintime b0, b1, b2;
struct timespec ts;
binuptime(&b0);
binuptime(&b0);
binuptime(&b1);
u1 = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
for (i = 1; i < 1000; i++)
u2 = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
binuptime(&b2);
u2 = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
bintime_sub(&b2, &b1);
bintime_sub(&b1, &b0);
bintime_sub(&b2, &b1);
bintime2timespec(&b2, &ts);
device_printf(sc->dev, "%ld.%09ld: %u ... %u = %u\n",
(long)ts.tv_sec, ts.tv_nsec, u1, u2, u2 - u1);
device_printf(sc->dev, "time per call: %ld ns\n", ts.tv_nsec / 1000);
}
static device_method_t acpi_hpet_methods[] = {
/* Device interface */
DEVMETHOD(device_identify, acpi_hpet_identify),
DEVMETHOD(device_probe, acpi_hpet_probe),
DEVMETHOD(device_attach, acpi_hpet_attach),
DEVMETHOD(device_detach, acpi_hpet_detach),
DEVMETHOD(device_suspend, acpi_hpet_suspend),
DEVMETHOD(device_resume, acpi_hpet_resume),
{0, 0}
};
static driver_t acpi_hpet_driver = {
"acpi_hpet",
acpi_hpet_methods,
sizeof(struct acpi_hpet_softc),
};
DRIVER_MODULE(acpi_hpet, acpi, acpi_hpet_driver, acpi_hpet_devclass, 0, 0);
MODULE_DEPEND(acpi_hpet, acpi, 1, 1, 1);