2 files changed, 20 insertions, 18 deletions

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index b09eee2281c5..492f581fe6ba 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -1853,21 +1853,6 @@ source "fs/Kconfig.binfmt"
 config TRAD_SIGNALS
         bool
 
-config BUILD_ELF64
-        bool "Use 64-bit ELF format for building"
-        depends on 64BIT
-        help
-          A 64-bit kernel is usually built using the 64-bit ELF binary object
-          format as it's one that allows arbitrary 64-bit constructs.  For
-          kernels that are loaded within the KSEG compatibility segments the
-          32-bit ELF format can optionally be used resulting in a somewhat
-          smaller binary, but this option is not explicitly supported by the
-          toolchain and since binutils 2.14 it does not even work at all.
-
-          Say Y to use the 64-bit format or N to use the 32-bit one.
-
-          If unsure say Y.
-
 config BINFMT_IRIX
         bool "Include IRIX binary compatibility"
         depends on CPU_BIG_ENDIAN && 32BIT && BROKEN
diff --git a/arch/mips/Makefile b/arch/mips/Makefile
index d5d5831b6e24..4337c492ed1b 100644
--- a/arch/mips/Makefile
+++ b/arch/mips/Makefile
@@ -60,9 +60,6 @@ vmlinux-32		= vmlinux.32
 vmlinux-64              = vmlinux
 
 cflags-y                += -mabi=64
-ifndef CONFIG_BUILD_ELF64
-cflags-y                += $(call cc-option,-msym32)
-endif
 endif
 
 all-$(CONFIG_BOOT_ELF32)        := $(vmlinux-32)
@@ -576,6 +573,26 @@ else
 JIFFIES                 = jiffies_64
 endif
 
+#
+# Automatically detect the build format. By default we choose
+# the elf format according to the load address.
+# We can always force a build with a 64-bits symbol format by
+# passing 'BUILD_ELF32=no' option to the make's command line.
+#
+ifdef CONFIG_64BIT
+  ifndef BUILD_ELF32
+    ifeq ($(shell expr $(load-y) \< 0xffffffff80000000), 0)
+      BUILD_ELF32 = y
+    endif
+  endif
+
+  ifeq ($(BUILD_ELF32), y)
+    cflags-y += -msym32
+  else
+    cflags-y += -DCONFIG_BUILD_ELF64
+  endif
+endif
+
 AFLAGS          += $(cflags-y)
 CFLAGS          += $(cflags-y) \
                         -D"VMLINUX_LOAD_ADDRESS=$(load-y)"