Dear Shawn Guo,

On Tue, Mar 13, 2012 at 11:23:51AM -0600, Grant Likely wrote:
...

quoted

quoted

+	apb@80000000 {
+		compatible = "simple-bus";
+		#address-cells = <1>;
+		#size-cells = <1>;
+		reg = <0x80000000 0x80000>;
+		ranges;
+
+		apbh@80000000 {
+			compatible = "simple-bus";
+			#address-cells = <1>;
+			#size-cells = <1>;
+			reg = <0x80000000 0x3c900>;
+			ranges;
+
+			icoll: interrupt-controller@80000000 {
+				compatible = "fsl,imx28-icoll";
+				interrupt-controller;
+				#interrupt-cells = <1>;
+				reg = <0x80000000 0x2000>;
+			};
+		};
+
+		apbx@80040000 {
+			compatible = "simple-bus";
+			#address-cells = <1>;
+			#size-cells = <1>;
+			reg = <0x80040000 0x40000>;
+			ranges;
+
+			uart1: uart@80074000 {
+				compatible = "arm,pl011", "arm,primecell";
+				reg = <0x80074000 0x2000>;
+				interrupts = <47>;
+			};
+		};

What is the purpose of the apbh and apbx busses?  Will more device nodes
get added to them later, or does each only contain a single device?

Since our ultimate goal is to convert mach-mxs over to device tree,
I would also suggest we have all the hardware blocks defined in dts
from the beginning.

Agreed.

Best regards,
Marek Vasut