NetBSD-5.0.2/sys/arch/x86/x86/coretemp.c
/* $NetBSD: coretemp.c,v 1.11 2008/09/23 22:14:09 christos Exp $ */
/*-
* Copyright (c) 2007 Juan Romero Pardines.
* Copyright (c) 2007 Rui Paulo <rpaulo@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 ``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 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: src/sys/dev/coretemp/coretemp.c,v 1.4 2007/10/15 20:00:21 netchild Exp $
*
*/
/*
* Device driver for Intel's On Die thermal sensor via MSR.
* First introduced in Intel's Core line of processors.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: coretemp.c,v 1.11 2008/09/23 22:14:09 christos Exp $");
#include <sys/param.h>
#include <sys/kmem.h>
#include <sys/xcall.h>
#include <sys/cpu.h>
#include <dev/sysmon/sysmonvar.h>
#include <machine/cpuvar.h>
#include <machine/specialreg.h>
#include <machine/cpufunc.h>
struct coretemp_softc {
struct cpu_info *sc_ci;
struct sysmon_envsys *sc_sme;
envsys_data_t sc_sensor;
char sc_dvname[32];
int sc_tjmax;
};
static void coretemp_refresh(struct sysmon_envsys *, envsys_data_t *);
static void coretemp_refresh_xcall(void *, void *);
void
coretemp_register(struct cpu_info *ci)
{
struct coretemp_softc *sc;
uint32_t regs[4];
uint64_t msr;
int cpumodel, cpumask;
/*
* CPUID 0x06 returns 1 if the processor has on-die thermal
* sensors. EBX[0:3] contains the number of sensors.
*/
x86_cpuid(0x06, regs);
if ((regs[0] & 0x1) != 1)
return;
sc = kmem_zalloc(sizeof(struct coretemp_softc), KM_NOSLEEP);
if (!sc)
return;
(void)snprintf(sc->sc_dvname, sizeof(sc->sc_dvname), "coretemp%d",
(int)device_unit(ci->ci_dev));
cpumodel = CPUID2MODEL(ci->ci_signature);
/* extended model */
cpumodel += CPUID2EXTMODEL(ci->ci_signature);
cpumask = ci->ci_signature & 15;
/*
* Check for errata AE18.
* "Processor Digital Thermal Sensor (DTS) Readout stops
* updating upon returning from C3/C4 state."
*
* Adapted from the Linux coretemp driver.
*/
if (cpumodel == 0xe && cpumask < 0xc) {
msr = rdmsr(MSR_BIOS_SIGN);
msr = msr >> 32;
if (msr < 0x39) {
aprint_debug("%s: not supported (Intel errata AE18), "
"try updating your BIOS\n", sc->sc_dvname);
goto bad;
}
}
/*
* On some Core 2 CPUs, there's an undocumented MSR that
* can tell us if Tj(max) is 100 or 85.
*
* The if-clause for CPUs having the MSR_IA32_EXT_CONFIG was adapted
* from the Linux coretemp driver.
*/
sc->sc_tjmax = 100;
if ((cpumodel == 0xf && cpumask >= 2) || cpumodel == 0xe) {
msr = rdmsr(MSR_IA32_EXT_CONFIG);
if (msr & (1 << 30))
sc->sc_tjmax = 85;
}
/*
* Check if the MSR contains thermal reading valid bit, this
* avoid false positives on systems that fake up a compatible
* CPU that doesn't have access to these MSRs; such as VMWare.
*/
msr = rdmsr(MSR_THERM_STATUS);
if ((msr & __BIT(31)) == 0)
goto bad;
sc->sc_ci = ci;
/*
* Only a temperature sensor and monitor for a critical state.
*/
sc->sc_sensor.units = ENVSYS_STEMP;
sc->sc_sensor.flags = ENVSYS_FMONCRITICAL;
sc->sc_sensor.monitor = true;
(void)snprintf(sc->sc_sensor.desc, sizeof(sc->sc_sensor.desc),
"%s temperature", device_xname(ci->ci_dev));
sc->sc_sme = sysmon_envsys_create();
if (sysmon_envsys_sensor_attach(sc->sc_sme, &sc->sc_sensor)) {
sysmon_envsys_destroy(sc->sc_sme);
goto bad;
}
/*
* Hook into the system monitor.
*/
sc->sc_sme->sme_name = sc->sc_dvname;
sc->sc_sme->sme_cookie = sc;
sc->sc_sme->sme_refresh = coretemp_refresh;
if (sysmon_envsys_register(sc->sc_sme)) {
aprint_error("%s: unable to register with sysmon\n",
sc->sc_dvname);
sysmon_envsys_destroy(sc->sc_sme);
goto bad;
}
return;
bad:
kmem_free(sc, sizeof(struct coretemp_softc));
}
static void
coretemp_refresh(struct sysmon_envsys *sme, envsys_data_t *edata)
{
struct coretemp_softc *sc = sme->sme_cookie;
uint64_t where;
where = xc_unicast(0, coretemp_refresh_xcall, sc, edata, sc->sc_ci);
xc_wait(where);
}
static void
coretemp_refresh_xcall(void *arg0, void *arg1)
{
struct coretemp_softc *sc = (struct coretemp_softc *)arg0;
envsys_data_t *edata = (envsys_data_t *)arg1;
uint64_t msr;
/*
* The digital temperature reading is located at bit 16
* of MSR_THERM_STATUS.
*
* There is a bit on that MSR that indicates whether the
* temperature is valid or not.
*
* The temperature is computed by subtracting the temperature
* reading by Tj(max).
*/
msr = rdmsr(MSR_THERM_STATUS);
/*
* Check for Thermal Status and Thermal Status Log.
*/
if ((msr & 0x3) == 0x3)
aprint_debug("%s: PROCHOT asserted\n", sc->sc_dvname);
/*
* Bit 31 contains "Reading valid"
*/
if (((msr >> 31) & 0x1) == 1) {
/*
* Starting on bit 16 and ending on bit 22.
*/
edata->value_cur = sc->sc_tjmax - ((msr >> 16) & 0x7f);
/*
* Convert to mK.
*/
edata->value_cur *= 1000000;
edata->value_cur += 273150000;
edata->state = ENVSYS_SVALID;
} else
edata->state = ENVSYS_SINVALID;
/*
* Check for Critical Temperature Status and Critical
* Temperature Log.
* It doesn't really matter if the current temperature is
* invalid because the "Critical Temperature Log" bit will
* tell us if the Critical Temperature has been reached in
* past. It's not directly related to the current temperature.
*
* If we reach a critical level, send a critical event to
* powerd(8) (if running).
*/
if (((msr >> 4) & 0x3) == 0x3)
edata->state = ENVSYS_SCRITICAL;
}