diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index 524b80722fd0..787515c6770e 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -541,17 +541,6 @@ config DEFAULT_MEM_START
 
 	  If unsure, leave the default value here.
 
-config DEFAULT_MEM_SIZE
-	hex "Maximal size of the default memory area"
-	depends on PLATFORM_WANT_DEFAULT_MEM
-	default 0x04000000
-	help
-	  This is the size of the default memory area.
-	  Default memory area has platform-specific meaning, it may be used
-	  for e.g. early cache initialization.
-
-	  If unsure, leave the default value here.
-
 config XTFPGA_LCD
 	bool "Enable XTFPGA LCD driver"
 	depends on XTENSA_PLATFORM_XTFPGA
diff --git a/arch/xtensa/configs/nommu_kc705_defconfig b/arch/xtensa/configs/nommu_kc705_defconfig
index 610f622d3c84..f3fc4f970ca8 100644
--- a/arch/xtensa/configs/nommu_kc705_defconfig
+++ b/arch/xtensa/configs/nommu_kc705_defconfig
@@ -40,7 +40,6 @@ CONFIG_CMDLINE_BOOL=y
 CONFIG_CMDLINE="earlycon=uart8250,mmio32native,0x9d050020,115200n8 console=ttyS0,115200n8 ip=dhcp root=/dev/nfs rw debug memmap=256M@0x60000000"
 CONFIG_USE_OF=y
 CONFIG_BUILTIN_DTB="kc705_nommu"
-CONFIG_DEFAULT_MEM_SIZE=0x10000000
 CONFIG_BINFMT_FLAT=y
 CONFIG_NET=y
 CONFIG_PACKET=y
diff --git a/arch/xtensa/platforms/iss/include/platform/hardware.h b/arch/xtensa/platforms/iss/include/platform/hardware.h
index 6930c12adc16..9acea2508c05 100644
--- a/arch/xtensa/platforms/iss/include/platform/hardware.h
+++ b/arch/xtensa/platforms/iss/include/platform/hardware.h
@@ -20,7 +20,6 @@
  */
 
 #define PLATFORM_DEFAULT_MEM_START	0x00000000
-#define PLATFORM_DEFAULT_MEM_SIZE	0x08000000
 
 /*
  * Interrupt configuration.
diff --git a/arch/xtensa/platforms/xt2000/include/platform/hardware.h b/arch/xtensa/platforms/xt2000/include/platform/hardware.h
index 886ef156ded3..4ad16bfc63b8 100644
--- a/arch/xtensa/platforms/xt2000/include/platform/hardware.h
+++ b/arch/xtensa/platforms/xt2000/include/platform/hardware.h
@@ -22,7 +22,6 @@
  */
 
 #define PLATFORM_DEFAULT_MEM_START 0x00000000
-#define PLATFORM_DEFAULT_MEM_SIZE 0x08000000
 
 /*
  * Number of platform IRQs
diff --git a/arch/xtensa/platforms/xtfpga/include/platform/hardware.h b/arch/xtensa/platforms/xtfpga/include/platform/hardware.h
index 1fda7e20dfcb..cbf3cddafeaf 100644
--- a/arch/xtensa/platforms/xtfpga/include/platform/hardware.h
+++ b/arch/xtensa/platforms/xtfpga/include/platform/hardware.h
@@ -20,7 +20,6 @@
 /* Memory configuration. */
 
 #define PLATFORM_DEFAULT_MEM_START __XTENSA_UL(CONFIG_DEFAULT_MEM_START)
-#define PLATFORM_DEFAULT_MEM_SIZE  __XTENSA_UL(CONFIG_DEFAULT_MEM_SIZE)
 
 /* Interrupt configuration. */