diff --git a/target/linux/ath79/patches-5.10/0040-ath79-sgmii-config.patch b/target/linux/ath79/patches-5.10/0040-ath79-sgmii-config.patch
new file mode 100644
index 00000000000..bf7cbf2716a
--- /dev/null
+++ b/target/linux/ath79/patches-5.10/0040-ath79-sgmii-config.patch
@@ -0,0 +1,9 @@
+--- a/arch/mips/include/asm/mach-ath79/ar71xx_regs.h
++++ b/arch/mips/include/asm/mach-ath79/ar71xx_regs.h
+@@ -1376,5 +1376,6 @@
+ 
+ #define QCA956X_SGMII_CONFIG_MODE_CTRL_SHIFT	0
+ #define QCA956X_SGMII_CONFIG_MODE_CTRL_MASK	0x7
++#define QCA956X_SGMII_CONFIG_MODE_CTRL_SGMII_MAC	0x2
+ 
+ #endif /* __ASM_MACH_AR71XX_REGS_H */