arm64: build with baremetal linker target instead of Linux when available
authorOlof Johansson <olof@lixom.net>
Fri, 13 Jul 2018 15:30:33 +0000 (08:30 -0700)
committerWill Deacon <will.deacon@arm.com>
Mon, 23 Jul 2018 14:30:19 +0000 (15:30 +0100)
Not all toolchains have the baremetal elf targets, RedHat/Fedora ones
in particular. So, probe for whether it's available and use the previous
(linux) targets if it isn't.

Reported-by: Laura Abbott <labbott@redhat.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Paul Kocialkowski <contact@paulk.fr>
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Will Deacon <will.deacon@arm.com>
arch/arm64/Makefile
scripts/Kbuild.include

index 4527226..99a1d85 100644 (file)
@@ -60,15 +60,16 @@ ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
 KBUILD_CPPFLAGS        += -mbig-endian
 CHECKFLAGS     += -D__AARCH64EB__
 AS             += -EB
-LD             += -EB
-LDFLAGS                += -maarch64linuxb
+# Prefer the baremetal ELF build target, but not all toolchains include
+# it so fall back to the standard linux version if needed.
+LDFLAGS                += -EB $(call ld-option, -maarch64elfb, -maarch64linuxb)
 UTS_MACHINE    := aarch64_be
 else
 KBUILD_CPPFLAGS        += -mlittle-endian
 CHECKFLAGS     += -D__AARCH64EL__
 AS             += -EL
-LD             += -EL
-LDFLAGS                += -maarch64linux
+# Same as above, prefer ELF but fall back to linux target if needed.
+LDFLAGS                += -EL $(call ld-option, -maarch64elf, -maarch64linux)
 UTS_MACHINE    := aarch64
 endif
 
index c8156d6..1e13f50 100644 (file)
@@ -163,8 +163,8 @@ cc-ldoption = $(call try-run,\
        $(CC) $(1) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))
 
 # ld-option
-# Usage: LDFLAGS += $(call ld-option, -X)
-ld-option = $(call try-run, $(LD) $(LDFLAGS) $(1) -v,$(1),$(2))
+# Usage: LDFLAGS += $(call ld-option, -X, -Y)
+ld-option = $(call try-run, $(LD) $(LDFLAGS) $(1) -v,$(1),$(2),$(3))
 
 # ar-option
 # Usage: KBUILD_ARFLAGS := $(call ar-option,D)