[RFC PATCH 4/4] arm64: efi: enable generic EFI compressed boot

[Ard Biesheuvel]

Wire up the generic EFI zboot support for arm64.

Signed-off-by: Ard Biesheuvel <ardb at kernel.org>
---
 arch/arm64/Makefile      |  5 +++++
 arch/arm64/boot/Makefile | 17 ++++++++++++++++-
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
index 2f1de88651e6..c9580f78439f 100644
--- a/arch/arm64/Makefile
+++ b/arch/arm64/Makefile
@@ -162,6 +162,11 @@ Image: vmlinux
 Image.%: Image
 	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
 
+ifneq ($(CONFIG_EFI_ZBOOT),)
+zImage.efi: Image
+	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
+endif
+
 install: install-image := Image
 zinstall: install-image := Image.gz
 install zinstall:
diff --git a/arch/arm64/boot/Makefile b/arch/arm64/boot/Makefile
index ebe80faab883..81500267ab79 100644
--- a/arch/arm64/boot/Makefile
+++ b/arch/arm64/boot/Makefile
@@ -16,7 +16,7 @@
 
 OBJCOPYFLAGS_Image :=-O binary -R .note -R .note.gnu.build-id -R .comment -S
 
-targets := Image Image.bz2 Image.gz Image.lz4 Image.lzma Image.lzo
+targets := Image Image.bz2 Image.gz Image.lz4 Image.lzma Image.lzo zImage.efi
 
 $(obj)/Image: vmlinux FORCE
 	$(call if_changed,objcopy)
@@ -35,3 +35,18 @@ $(obj)/Image.lzma: $(obj)/Image FORCE
 
 $(obj)/Image.lzo: $(obj)/Image FORCE
 	$(call if_changed,lzo)
+
+OBJCOPYFLAGS_Image.gz.o := -O elf64-littleaarch64 -I binary \
+			   --rename-section .data=.gzdata,load,alloc,readonly,contents
+$(obj)/Image.gz.o: $(obj)/Image.gz FORCE
+	$(call if_changed,objcopy)
+
+ZBOOT_DEPS := memcpy.o memset.o strnlen.o
+$(obj)/zImage.efi.elf: $(obj)/Image.gz.o $(addprefix $(objtree)/arch/arm64/lib/,$(ZBOOT_DEPS))
+	$(Q)$(LD) -T $(srctree)/drivers/firmware/efi/libstub/zboot.lds \
+		-o $@ $^ $(objtree)/drivers/firmware/efi/libstub/lib.a \
+		--defsym=pe_machine_type=0xaa64
+
+$(obj)/zImage.efi: OBJCOPYFLAGS := -O binary
+$(obj)/zImage.efi: $(obj)/zImage.efi.elf FORCE
+	$(call if_changed,objcopy)
-- 
2.30.2