cpufreq / highbank: add support for highbank cpufreq

Highbank processors depend on the external ECME to perform voltage
management based on a requested frequency. Communication between the
A9 cores and the ECME happens over the pl320 IPC channel.

Signed-off-by: Mark Langsdorf <mark.langsdorf@calxeda.com>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/cpufreq/cpufreq-cpu0.c b/drivers/cpufreq/cpufreq-cpu0.c
index debc5a7..38ae178 100644
--- a/drivers/cpufreq/cpufreq-cpu0.c
+++ b/drivers/cpufreq/cpufreq-cpu0.c
@@ -182,7 +182,11 @@
 	struct device_node *np;
 	int ret;
 
-	np = of_find_node_by_path("/cpus/cpu@0");
+	for_each_child_of_node(of_find_node_by_path("/cpus"), np) {
+		if (of_get_property(np, "operating-points", NULL))
+			break;
+	}
+
 	if (!np) {
 		pr_err("failed to find cpu0 node\n");
 		return -ENOENT;