--- zzzz-none-000/linux-4.9.218/drivers/base/Kconfig	2020-04-02 15:20:41.000000000 +0000
+++ seale-7590ax-750/linux-4.9.218/drivers/base/Kconfig	2023-03-29 10:59:06.000000000 +0000
@@ -244,7 +244,7 @@
 source "drivers/base/regmap/Kconfig"
 
 config DMA_SHARED_BUFFER
-	bool
+	tristate
 	default n
 	select ANON_INODES
 	help
@@ -279,6 +279,11 @@
 if  DMA_CMA
 comment "Default contiguous memory area size:"
 
+config CMA_LIMIT_256M
+    bool "Limit CMA region to beginning of 256MB physical memory"
+    depends on CMA
+    default y
+
 config CMA_SIZE_MBYTES
 	int "Size in Mega Bytes"
 	depends on !CMA_SIZE_SEL_PERCENTAGE