Make a pass through all drivers checking specs for desired behavior on

SMP systems.  It appears all drivers except ichss should attach to each
CPU and that settings should be performed on each CPU.  Add comments about
this.  Also, add a guard for p4tcc's identify method being called more than
once.

1 files changed, 5 insertions, 1 deletions

diff --git a/sys/dev/cpufreq/ichss.c b/sys/dev/cpufreq/ichss.c
index b8d3542..d38ed52 100644
--- a/sys/dev/cpufreq/ichss.c
+++ b/sys/dev/cpufreq/ichss.c
@@ -166,7 +166,11 @@ ichss_pci_probe(device_t dev)
 	if (devclass_get_device(ichss_devclass, 0))
 		return (ENXIO);
 
-	/* Add a child under the CPU parent. */
+	/*
+	 * Add a child under the CPU parent.  It appears that ICH SpeedStep
+	 * only requires a single CPU to set the value (since the chipset
+	 * is shared by all CPUs.)  Thus, we only add a child to cpu 0.
+	 */
 	parent = devclass_get_device(devclass_find("cpu"), 0);
 	KASSERT(parent != NULL, ("cpu parent is NULL"));
 	child = BUS_ADD_CHILD(parent, 0, "ichss", 0);