diff --git a/arch/riscv/include/asm/cacheflush.h b/arch/riscv/include/asm/cacheflush.h
index a60acaecfedab6..de55d6b8deebf4 100644
--- a/arch/riscv/include/asm/cacheflush.h
+++ b/arch/riscv/include/asm/cacheflush.h
@@ -42,6 +42,8 @@ void flush_icache_mm(struct mm_struct *mm, bool local);
 
 #endif /* CONFIG_SMP */
 
+extern unsigned int riscv_cbom_block_size;
+
 #ifdef CONFIG_RISCV_ISA_ZICBOM
 void riscv_init_cbom_blocksize(void);
 #else
diff --git a/arch/riscv/mm/cacheflush.c b/arch/riscv/mm/cacheflush.c
index 6cb7d96ad9c7bc..336c5deea8700b 100644
--- a/arch/riscv/mm/cacheflush.c
+++ b/arch/riscv/mm/cacheflush.c
@@ -3,6 +3,8 @@
  * Copyright (C) 2017 SiFive
  */
 
+#include <linux/of.h>
+#include <linux/of_device.h>
 #include <asm/cacheflush.h>
 
 #ifdef CONFIG_SMP
@@ -86,3 +88,40 @@ void flush_icache_pte(pte_t pte)
 		flush_icache_all();
 }
 #endif /* CONFIG_MMU */
+
+unsigned int riscv_cbom_block_size = L1_CACHE_BYTES;
+
+#ifdef CONFIG_RISCV_ISA_ZICBOM
+void riscv_init_cbom_blocksize(void)
+{
+	struct device_node *node;
+	int ret;
+	u32 val;
+
+	for_each_of_cpu_node(node) {
+		unsigned long hartid;
+		int cbom_hartid;
+
+		ret = riscv_of_processor_hartid(node, &hartid);
+		if (ret)
+			continue;
+
+		if (hartid < 0)
+			continue;
+
+		/* set block-size for cbom extension if available */
+		ret = of_property_read_u32(node, "riscv,cbom-block-size", &val);
+		if (ret)
+			continue;
+
+		if (!riscv_cbom_block_size) {
+			riscv_cbom_block_size = val;
+			cbom_hartid = hartid;
+		} else {
+			if (riscv_cbom_block_size != val)
+				pr_warn("cbom-block-size mismatched between harts %d and %lu\n",
+					cbom_hartid, hartid);
+		}
+	}
+}
+#endif
diff --git a/arch/riscv/mm/dma-noncoherent.c b/arch/riscv/mm/dma-noncoherent.c
index cd2225304c82e2..3f502a1a68b179 100644
--- a/arch/riscv/mm/dma-noncoherent.c
+++ b/arch/riscv/mm/dma-noncoherent.c
@@ -8,11 +8,8 @@
 #include <linux/dma-direct.h>
 #include <linux/dma-map-ops.h>
 #include <linux/mm.h>
-#include <linux/of.h>
-#include <linux/of_device.h>
 #include <asm/cacheflush.h>
 
-static unsigned int riscv_cbom_block_size = L1_CACHE_BYTES;
 static bool noncoherent_supported;
 
 void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
@@ -75,41 +72,6 @@ void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
 	dev->dma_coherent = coherent;
 }
 
-#ifdef CONFIG_RISCV_ISA_ZICBOM
-void riscv_init_cbom_blocksize(void)
-{
-	struct device_node *node;
-	int ret;
-	u32 val;
-
-	for_each_of_cpu_node(node) {
-		unsigned long hartid;
-		int cbom_hartid;
-
-		ret = riscv_of_processor_hartid(node, &hartid);
-		if (ret)
-			continue;
-
-		if (hartid < 0)
-			continue;
-
-		/* set block-size for cbom extension if available */
-		ret = of_property_read_u32(node, "riscv,cbom-block-size", &val);
-		if (ret)
-			continue;
-
-		if (!riscv_cbom_block_size) {
-			riscv_cbom_block_size = val;
-			cbom_hartid = hartid;
-		} else {
-			if (riscv_cbom_block_size != val)
-				pr_warn("cbom-block-size mismatched between harts %d and %lu\n",
-					cbom_hartid, hartid);
-		}
-	}
-}
-#endif
-
 void riscv_noncoherent_supported(void)
 {
 	noncoherent_supported = true;