PERFORCE change 124473 for review

[Rui Paulo]

http://perforce.freebsd.org/chv.cgi?CH=124473

Change 124473 by rpaulo at rpaulo_epsilon on 2007/08/01 16:06:30

	Try to guess some CPUs that have Tj(max) == 85.
	
	Obtained from:	OpenBSD, Linux

Affected files ...

.. //depot/projects/soc2007/rpaulo-macbook/dev/msrtemp/msrtemp.c#10 edit

Differences ...

==== //depot/projects/soc2007/rpaulo-macbook/dev/msrtemp/msrtemp.c#10 (text+ko) ====

@@ -23,7 +23,7 @@
  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  *
- * $P4: //depot/projects/soc2007/rpaulo-macbook/dev/msrtemp/msrtemp.c#9 $
+ * $P4: //depot/projects/soc2007/rpaulo-macbook/dev/msrtemp/msrtemp.c#10 $
  *
  */
 
@@ -52,6 +52,7 @@
 
 struct msrtemp_softc {
 	device_t	sc_dev;
+	int		sc_tjmax;
 	struct sysctl_oid *sc_oid;
 };
 
@@ -63,7 +64,7 @@
 static int	msrtemp_attach(device_t dev);
 static int	msrtemp_detach(device_t dev);
 
-static int	msrtemp_get_temp(int cpu);
+static int	msrtemp_get_temp(device_t dev);
 static int	msrtemp_get_temp_sysctl(SYSCTL_HANDLER_ARGS);
 
 static device_method_t msrtemp_methods[] = {
@@ -131,10 +132,24 @@
 {
 	struct msrtemp_softc *sc = device_get_softc(dev);
 	device_t pdev;
+	uint64_t msr;
 
 	pdev = device_get_parent(dev);
 
+
 	/*
+	 * On some Core 2 CPUs, there's an undocumented MSR that
+	 * can tell us if Tj(max) is 100 or 85.
+	 *
+	 * This is only valid for some steppings.
+	 */
+	msr = rdmsr(MSR_EXT_CONFIG);
+	if ((msr >> 30) & 0x1)
+		sc->sc_tjmax = 85;
+	else
+		sc->sc_tjmax = 100;
+		
+	/*
 	 * Add the "temperature" MIB to dev.cpu.N.
 	 */
 	sc->sc_oid = SYSCTL_ADD_PROC(device_get_sysctl_ctx(pdev),
@@ -159,9 +174,11 @@
 
 
 static int
-msrtemp_get_temp(int cpu)
+msrtemp_get_temp(device_t dev)
 {
 	uint64_t temp;
+	int cpu = device_get_unit(dev);
+	struct msrtemp_softc *sc = device_get_softc(dev);
 
 	thread_lock(curthread);
 	sched_bind(curthread, cpu);
@@ -176,10 +193,6 @@
 	 *
 	 * The temperature is computed by subtracting the temperature
 	 * reading by Tj(max).
-	 *
-	 * 100 is Tj(max). On some CPUs it should be 85, but Intel
-	 * doesn't supply that info, so right now, we are using 
-	 * 100 degC for everyone.
 	 */
 	temp = rdmsr(MSR_THERM_STATUS);
 
@@ -191,7 +204,7 @@
 		 * Starting on bit 16 and ending on bit 22.
 		 * We use 0x7f to ignore the minus signal.
 		 */
-		temp = 100 - ((temp >> 16) & 0x7f);
+		temp = sc->sc_tjmax - ((temp >> 16) & 0x7f);
 		return (int) temp;
 	}
 
@@ -204,7 +217,7 @@
 	device_t dev = (device_t) arg1;
 	int temp;
 
-	temp = msrtemp_get_temp(device_get_unit(dev));
+	temp = msrtemp_get_temp(dev);
 
 	return sysctl_handle_int(oidp, &temp, 0, req);
 }