[PATCH v4 6/7] ARM: dts: microchip: sama5d27_wlsom1: read MAC address from QSPI SFDP
From: Manikandan Muralidharan
Date: Tue Jun 30 2026 - 05:38:53 EST
Describe the QSPI flash SFDP as an NVMEM provider with the
microchip,sst26vf-sfdp-eui layout, which exposes the factory-programmed
EUI-48 as a "mac-address" cell, and point macb0 at it through
nvmem-cells. This yields a stable MAC address on boards where U-Boot does
not program one, instead of falling back to a random address.
Signed-off-by: Manikandan Muralidharan <manikandan.m@xxxxxxxxxxxxx>
---
arch/arm/boot/dts/microchip/at91-sama5d27_wlsom1.dtsi | 11 +++++++++++
.../boot/dts/microchip/at91-sama5d27_wlsom1_ek.dts | 2 ++
2 files changed, 13 insertions(+)
diff --git a/arch/arm/boot/dts/microchip/at91-sama5d27_wlsom1.dtsi b/arch/arm/boot/dts/microchip/at91-sama5d27_wlsom1.dtsi
index 062aa02a98ed..6016d7f2a39c 100644
--- a/arch/arm/boot/dts/microchip/at91-sama5d27_wlsom1.dtsi
+++ b/arch/arm/boot/dts/microchip/at91-sama5d27_wlsom1.dtsi
@@ -240,6 +240,17 @@ qspi1_flash: flash@0 {
m25p,fast-read;
status = "disabled";
+ sfdp {
+ compatible = "jedec,sfdp";
+
+ nvmem-layout {
+ compatible = "microchip,sst26vf-sfdp-eui";
+
+ mac_address_eui48: mac-address {
+ };
+ };
+ };
+
partitions {
compatible = "fixed-partitions";
#address-cells = <1>;
diff --git a/arch/arm/boot/dts/microchip/at91-sama5d27_wlsom1_ek.dts b/arch/arm/boot/dts/microchip/at91-sama5d27_wlsom1_ek.dts
index 35a933eec573..5e87bf04bc47 100644
--- a/arch/arm/boot/dts/microchip/at91-sama5d27_wlsom1_ek.dts
+++ b/arch/arm/boot/dts/microchip/at91-sama5d27_wlsom1_ek.dts
@@ -97,6 +97,8 @@ uart6: serial@200 {
&macb0 {
status = "okay";
+ nvmem-cells = <&mac_address_eui48>;
+ nvmem-cell-names = "mac-address";
};
&pioA {
--
2.43.0