svn commit: r366723 - head/sys/dev/iicbus

[Nathan Whitehorn]

Author: nwhitehorn
Date: Thu Oct 15 13:43:43 2020
New Revision: 366723
URL: https://svnweb.freebsd.org/changeset/base/366723

Log:
  Provide a slightly more-tolerant set of thermal parameters for PowerMac
  motherboard temperatures. In particular, the U4 northbridge die is very
  hard to cool or heat effectively with fans and is not responsive to load.
  It generally sits around 64C, where it seems happy, so (like Linux) just
  declare that to be its target temperature.
  
  This makes the PowerMac G5 much less loud, with no change in the
  temperatures of any system components.
  
  MFC after:	2 weeks

Modified:
  head/sys/dev/iicbus/max6690.c

Modified: head/sys/dev/iicbus/max6690.c
==============================================================================
--- head/sys/dev/iicbus/max6690.c	Thu Oct 15 12:48:30 2020	(r366722)
+++ head/sys/dev/iicbus/max6690.c	Thu Oct 15 13:43:43 2020	(r366723)
@@ -213,8 +213,17 @@ max6690_fill_sensor_prop(device_t dev)
 	for (j = 0; j < i; j++) {
 		sc->sc_sensors[j].dev = dev;
 
-		sc->sc_sensors[j].therm.target_temp = 400 + ZERO_C_TO_K;
-		sc->sc_sensors[j].therm.max_temp = 800 + ZERO_C_TO_K;
+		/*
+		 * Target value for "KODIAK DIODE" (= northbridge die) should
+		 * be 64C (value from Linux). It operates fine at that
+		 * temperature and has limited responsivity to the fan aimed at
+		 * it, so no point in trying to cool it to 40C.
+		 */
+		if (strcmp(sc->sc_sensors[j].therm.name, "KODIAK DIODE") == 0)
+			sc->sc_sensors[j].therm.target_temp = 640 + ZERO_C_TO_K;
+		else
+			sc->sc_sensors[j].therm.target_temp = 400 + ZERO_C_TO_K;
+		sc->sc_sensors[j].therm.max_temp = 850 + ZERO_C_TO_K;
 
 		sc->sc_sensors[j].therm.read =
 		    (int (*)(struct pmac_therm *))(max6690_sensor_read);