diff --git a/arch/blackfin/Kconfig b/arch/blackfin/Kconfig
index 785d8b4..b87634e 100644
--- a/arch/blackfin/Kconfig
+++ b/arch/blackfin/Kconfig
@@ -685,6 +685,8 @@
 	prompt "Uncached SDRAM region"
 	default DMA_UNCACHED_1M
 	depends on BFIN_DMA_5XX
+config DMA_UNCACHED_4M
+	bool "Enable 4M DMA region"
 config DMA_UNCACHED_2M
 	bool "Enable 2M DMA region"
 config DMA_UNCACHED_1M