--- /dev/null
+Index: linux-4.14.42/arch/mips/ath79/common.c
+===================================================================
+--- linux-4.14.42.orig/arch/mips/ath79/common.c
++++ linux-4.14.42/arch/mips/ath79/common.c
+@@ -34,11 +34,13 @@ EXPORT_SYMBOL_GPL(ath79_ddr_freq);
+
+ enum ath79_soc_type ath79_soc;
+ unsigned int ath79_soc_rev;
++EXPORT_SYMBOL_GPL(ath79_soc_rev);
+
+ void __iomem *ath79_pll_base;
+ void __iomem *ath79_reset_base;
+ EXPORT_SYMBOL_GPL(ath79_reset_base);
+-static void __iomem *ath79_ddr_base;
++void __iomem *ath79_ddr_base;
++EXPORT_SYMBOL_GPL(ath79_ddr_base);
+ static void __iomem *ath79_ddr_wb_flush_base;
+ static void __iomem *ath79_ddr_pci_win_base;
+
+Index: linux-4.14.42/arch/mips/include/asm/mach-ath79/ath79.h
+===================================================================
+--- linux-4.14.42.orig/arch/mips/include/asm/mach-ath79/ath79.h
++++ linux-4.14.42/arch/mips/include/asm/mach-ath79/ath79.h
+@@ -152,6 +152,7 @@ void ath79_ddr_wb_flush(unsigned int reg
+ void ath79_ddr_set_pci_windows(void);
+
+ extern void __iomem *ath79_pll_base;
++extern void __iomem *ath79_ddr_base;
+ extern void __iomem *ath79_reset_base;
+
+ static inline void ath79_pll_wr(unsigned reg, u32 val)