powerpc/boot: Add support for 64bit little endian wrapper
The code is only slightly modified : entry points now use the
FIXUP_ENDIAN trampoline to switch endian order. The 32bit wrapper
is kept for big endian kernels and 64bit is enforced for little
endian kernels with a PPC64_BOOT_WRAPPER config option.
The linker script is generated using the kernel preprocessor flags
to make use of the CONFIG_* definitions and the wrapper script is
modified to take into account the new elf64ppc format.
Finally, the zImage file is compiled as a position independent
executable (-pie) which makes it loadable at any address by the
firmware.
Signed-off-by: Cédric Le Goater <clg@fr.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile
index bed660d..a33c233 100644
--- a/arch/powerpc/boot/Makefile
+++ b/arch/powerpc/boot/Makefile
@@ -22,8 +22,14 @@
BOOTCFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
-fno-strict-aliasing -Os -msoft-float -pipe \
-fomit-frame-pointer -fno-builtin -fPIC -nostdinc \
- -isystem $(shell $(CROSS32CC) -print-file-name=include) \
- -mbig-endian
+ -isystem $(shell $(CROSS32CC) -print-file-name=include)
+ifdef CONFIG_PPC64_BOOT_WRAPPER
+BOOTCFLAGS += -m64
+endif
+ifdef CONFIG_CPU_BIG_ENDIAN
+BOOTCFLAGS += -mbig-endian
+endif
+
BOOTAFLAGS := -D__ASSEMBLY__ $(BOOTCFLAGS) -traditional -nostdinc
ifdef CONFIG_DEBUG_INFO
@@ -142,7 +148,11 @@
$(obj)/empty.c:
@touch $@
-$(obj)/zImage.lds $(obj)/zImage.coff.lds $(obj)/zImage.ps3.lds: $(obj)/%: $(srctree)/$(src)/%.S
+$(obj)/zImage.lds: $(obj)/%: $(srctree)/$(src)/%.S
+ $(CROSS32CC) $(cpp_flags) -E -Wp,-MD,$(depfile) -P -Upowerpc \
+ -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
+
+$(obj)/zImage.coff.lds $(obj)/zImage.ps3.lds : $(obj)/%: $(srctree)/$(src)/%.S
@cp $< $@
clean-files := $(zlib) $(zlibheader) $(zliblinuxheader) \