[PATCH v2 4/4] arm64: dts: rockchip: Derive GMAC MAC addresses from OTP on RK3576

[Alexey Charkov <alchark@flipper.net>]

Rockchip SoCs derive stable MAC addresses from the CPU ID in OTP memory,
which a bootloader would normally process and patch the live device tree
based on it. This depends on the particular bootloader implementation
though, and the derivation itself is not described in the device tree.

Add explicit nvmem layout for the CPU ID derived MAC addresses on RK3576,
so that any OS can implement the same derivation without depending on the
bootloader used.

Boards which store a MAC address of their own can override the reference
with a cell of their choosing.

Signed-off-by: Alexey Charkov <alchark@flipper.net>
---
 arch/arm64/boot/dts/rockchip/rk3576.dtsi | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/arm64/boot/dts/rockchip/rk3576.dtsi b/arch/arm64/boot/dts/rockchip/rk3576.dtsi
index d418bfc04097..aa6d867b5a30 100644
--- a/arch/arm64/boot/dts/rockchip/rk3576.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3576.dtsi
@@ -1845,6 +1845,8 @@ gmac0: ethernet@2a220000 {
 			interrupts = <GIC_SPI 293 IRQ_TYPE_LEVEL_HIGH>,
 				     <GIC_SPI 298 IRQ_TYPE_LEVEL_HIGH>;
 			interrupt-names = "macirq", "eth_wake_irq";
+			nvmem-cells = <&otp_mac_address 0>;
+			nvmem-cell-names = "mac-address";
 			power-domains = <&power RK3576_PD_SDGMAC>;
 			resets = <&cru SRST_A_GMAC0>;
 			reset-names = "stmmaceth";
@@ -1893,6 +1895,8 @@ gmac1: ethernet@2a230000 {
 			interrupts = <GIC_SPI 301 IRQ_TYPE_LEVEL_HIGH>,
 				     <GIC_SPI 306 IRQ_TYPE_LEVEL_HIGH>;
 			interrupt-names = "macirq", "eth_wake_irq";
+			nvmem-cells = <&otp_mac_address 1>;
+			nvmem-cell-names = "mac-address";
 			power-domains = <&power RK3576_PD_SDGMAC>;
 			resets = <&cru SRST_A_GMAC1>;
 			reset-names = "stmmaceth";
@@ -2131,6 +2135,14 @@ soc_tsadc_trim: soc-tsadc-trim@64 {
 				reg = <0x64 0x2>;
 				bits = <0 10>;
 			};
+
+			nvmem-layout {
+				compatible = "rockchip,rk3576-otp-cpuid";
+
+				otp_mac_address: mac-address {
+					#nvmem-cell-cells = <1>;
+				};
+			};
 		};
 
 		sai0: sai@2a600000 {

-- 
2.54.0