On 10/22/2012 08:45 PM, Andrew Lunn wrote:

Hi Gregory

quoted

+void __init set_secondary_cpus_clock(void)
+{
+	int cpu;
+	unsigned long rate;
+	struct clk *cpu_clk = NULL;
+	struct device_node *np = NULL;
+
+	cpu = smp_processor_id();
+	np = of_find_node_by_type(np, "cpu");
+	np = NULL;
+	while ((np = of_find_node_by_type(np, "cpu"))) {
+		const u32 *reg;
+		int len;
+		reg = of_get_property(np, "reg", &len);
+		if (!reg || len != 4) {
+			pr_err("%s missing reg property\n", np->full_name);
+			continue;
+		}
+		if (be32_to_cpup(reg) == cpu) {
+			cpu_clk = of_clk_get(np, 0);
+			break;
+		}
+	}
+	WARN_ON(IS_ERR(cpu_clk));
+	rate = clk_get_rate(cpu_clk);
+
+	/* set all the other CPU clk to the same rate than the boot CPU */
+	np = NULL;
+	while ((np = of_find_node_by_type(np, "cpu"))) {
+		const u32 *reg;
+		int len;
+		reg = of_get_property(np, "reg", &len);
+		if (!reg || len != 4) {
+			pr_err("%s missing reg property\n", np->full_name);
+			continue;
+		}
+		if (be32_to_cpup(reg) != cpu) {
+			cpu_clk = of_clk_get(np, 0);
+			clk_set_rate(cpu_clk, rate);
+		}

Maybe its hiding somewhere, but where is the clk_prepare_enable() for
this cpu_clk clock?

Well the clocks are always enable. In the clock framework, the cpu clocks
don't provide an enable function.
But maybe it is cleaner to call clk_prepare_enable() even if it does
nothing except update the usage count.

Thanks,

Gregory