diff --git a/soc/litex/litex_vexriscv/soc.h b/soc/litex/litex_vexriscv/soc.h
index 4334be4ec1c..060110bbdbe 100644
--- a/soc/litex/litex_vexriscv/soc.h
+++ b/soc/litex/litex_vexriscv/soc.h
@@ -103,6 +103,27 @@ static inline void litex_write32(unsigned int value, unsigned long addr)
 #endif
 }
 
+static inline void litex_write64(uint64_t value, unsigned long addr)
+{
+#if CONFIG_LITEX_CSR_DATA_WIDTH == 8
+	sys_write8(value >> 56, addr);
+	sys_write8(value >> 48, addr + 0x4);
+	sys_write8(value >> 40, addr + 0x8);
+	sys_write8(value >> 32, addr + 0xC);
+	sys_write8(value >> 24, addr + 0x10);
+	sys_write8(value >> 16, addr + 0x14);
+	sys_write8(value >> 8, addr + 0x18);
+	sys_write8(value, addr + 0x1C);
+#elif CONFIG_LITEX_CSR_DATA_WIDTH == 32
+	sys_write32(value >> 32, addr);
+	sys_write32(value, addr + 0x4);
+#elif CONFIG_LITEX_CSR_DATA_WIDTH >= 64
+	sys_write64(value, addr);
+#else
+#error Unsupported CSR data width
+#endif
+}
+
 /*
  * Operates on uint32_t values only
  * Size is in bytes and meaningful are 1, 2 or 4