Help with DTS file on MPC8313e-rdb board

[Joe Shmo]

Hello,
I need some help interpreting the DTS file for this
board such that I can change it to support our new
Phy.  Here is what the DTS file shows unmodified:

		mdio at 24520 {
			device_type = "mdio";
			compatible = "gianfar";
			reg = <24520 20>;
			#address-cells = <1>;
			#size-cells = <0>;
			phy1: ethernet-phy at 1 {
				interrupt-parent = < &ipic >;
				interrupts = <13 8>;
				reg = <1>;
				device_type = "ethernet-phy";
			};
			phy4: ethernet-phy at 4 {
				interrupt-parent = < &ipic >;
				interrupts = <14 8>;
				reg = <4>;
				device_type = "ethernet-phy";
			};
		};

		ethernet at 24000 {
			device_type = "network";
			model = "eTSEC";
			compatible = "gianfar";
			reg = <24000 1000>;
			local-mac-address = [ 00 00 00 00 00 00 ];
			interrupts = <25 8 24 8 23 8>;
			interrupt-parent = < &ipic >;
			phy-handle = < &phy1 >;
		};

		ethernet at 25000 {
			device_type = "network";
			model = "eTSEC";
			compatible = "gianfar";
			reg = <25000 1000>;
			local-mac-address = [ 00 00 00 00 00 00 ];
			interrupts = <22 8 21 8 20 8>;
			interrupt-parent = < &ipic >;
			phy-handle = < &phy4 >;
		};

What I don't know is what reg = <4> means.  Is that
the phy address or the interrupt?  For this board that
phy uses IRQ4 and has its address wired to 4.  I would
guess it is the IRQ since there is also a phy address
of 0x1c but that does not appear in this DTS file
anywhere.  

My phy is the National semi dp83848.  It does not use
an IRQ.  Should I replace this with zero?  Should I
take that line out of the DTS file?

Thanks.