dts: bcm2712-rpi: Move rpi-otp nodes onto a bus

The rpi-otp driver uses a virtualised, OTP-relative addressing scheme.
However, when instance nodes are children of "/soc" they appear to be
addressable directly by the host, which is wrong (but not in a way which
causes an error unless one goes looking for one).

Add a wrapper (bus) node without a "ranges" property to make the
separation clear.

See: #6196

Signed-off-by: Phil Elwell <[email protected]>

Author: pelwell

arch/arm/boot/dts/broadcom/bcm2712-rpi.dtsi

@@ -45,32 +45,38 @@
 		trickle-charge-microvolt = <0>;
 	};
 
-	nvmem_otp: nvmem_otp {
-		compatible = "raspberrypi,rpi-otp";
-		firmware = <&firmware>;
-		reg = <0 192>;
-		status = "okay";
-	};
+	nvmem {
+		compatible = "simple-bus";
+		#address-cells = <1>;
+		#size-cells = <1>;
 
-	nvmem_cust: nvmem_cust {
-		compatible = "raspberrypi,rpi-otp";
-		firmware = <&firmware>;
-		reg = <1 8>;
-		status = "okay";
-	};
+		nvmem_otp: nvmem_otp {
+			compatible = "raspberrypi,rpi-otp";
+			firmware = <&firmware>;
+			reg = <0 192>;
+			status = "okay";
+		};
 
-	nvmem_mac: nvmem_mac {
-		compatible = "raspberrypi,rpi-otp";
-		firmware = <&firmware>;
-		reg = <2 6>;
-		status = "okay";
-	};
+		nvmem_cust: nvmem_cust {
+			compatible = "raspberrypi,rpi-otp";
+			firmware = <&firmware>;
+			reg = <1 8>;
+			status = "okay";
+		};
 
-	nvmem_priv: nvmem_priv {
-		compatible = "raspberrypi,rpi-otp";
-		firmware = <&firmware>;
-		reg = <3 16>;
-		status = "okay";
+		nvmem_mac: nvmem_mac {
+			compatible = "raspberrypi,rpi-otp";
+			firmware = <&firmware>;
+			reg = <2 6>;
+			status = "okay";
+		};
+
+		nvmem_priv: nvmem_priv {
+			compatible = "raspberrypi,rpi-otp";
+			firmware = <&firmware>;
+			reg = <3 16>;
+			status = "okay";
+		};
 	};
 
 	/* Define these notional regulators for use by overlays, etc. */