linux/arch/arm/boot/compressed/Makefile
Nicolas Pitre 5ffb04f669 ARM: zImage: make sure appended DTB doesn't get overwritten by kernel .bss
The appended DTB gets relocated with the decompressor code to get out
of the way of the decompressed kernel.  However the kernel's .bss section
may be larger than the relocated code and data, and then the DTB gets
overwritten.  Let's make sure the relocation takes care of moving zImage
far enough so no such conflict with .bss occurs.

Thanks to Tony Lindgren <tony@atomide.com> for figuring out this issue.

While at it, let's clean up the code a bit so that the wont_overwrite
symbol is used while determining if a conflict exists, making the above
change more precise as well as eliminating some ARM/THUMB alternates.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Dave Martin <dave.martin@linaro.org>
Tested-by: Thomas Abraham <thomas.abraham@linaro.org>
2011-09-14 13:51:57 -04:00

162 lines
4.3 KiB
Makefile

#
# linux/arch/arm/boot/compressed/Makefile
#
# create a compressed vmlinuz image from the original vmlinux
#
OBJS =
# Ensure that MMCIF loader code appears early in the image
# to minimise that number of bocks that have to be read in
# order to load it.
ifeq ($(CONFIG_ZBOOT_ROM_MMCIF),y)
OBJS += mmcif-sh7372.o
endif
# Ensure that SDHI loader code appears early in the image
# to minimise that number of bocks that have to be read in
# order to load it.
ifeq ($(CONFIG_ZBOOT_ROM_SH_MOBILE_SDHI),y)
OBJS += sdhi-shmobile.o
OBJS += sdhi-sh7372.o
endif
AFLAGS_head.o += -DTEXT_OFFSET=$(TEXT_OFFSET)
HEAD = head.o
OBJS += misc.o decompress.o
FONTC = $(srctree)/drivers/video/console/font_acorn_8x8.c
#
# Architecture dependencies
#
ifeq ($(CONFIG_ARCH_ACORN),y)
OBJS += ll_char_wr.o font.o
endif
ifeq ($(CONFIG_ARCH_SHARK),y)
OBJS += head-shark.o ofw-shark.o
endif
ifeq ($(CONFIG_ARCH_P720T),y)
# Borrow this code from SA1100
OBJS += head-sa1100.o
endif
ifeq ($(CONFIG_ARCH_SA1100),y)
OBJS += head-sa1100.o
endif
ifeq ($(CONFIG_ARCH_VT8500),y)
OBJS += head-vt8500.o
endif
ifeq ($(CONFIG_CPU_XSCALE),y)
OBJS += head-xscale.o
endif
ifeq ($(CONFIG_PXA_SHARPSL_DETECT_MACH_ID),y)
OBJS += head-sharpsl.o
endif
ifeq ($(CONFIG_CPU_ENDIAN_BE32),y)
ifeq ($(CONFIG_CPU_CP15),y)
OBJS += big-endian.o
else
# The endian should be set by h/w design.
endif
endif
ifeq ($(CONFIG_ARCH_SHMOBILE),y)
OBJS += head-shmobile.o
endif
#
# We now have a PIC decompressor implementation. Decompressors running
# from RAM should not define ZTEXTADDR. Decompressors running directly
# from ROM or Flash must define ZTEXTADDR (preferably via the config)
# FIXME: Previous assignment to ztextaddr-y is lost here. See SHARK
ifeq ($(CONFIG_ZBOOT_ROM),y)
ZTEXTADDR := $(CONFIG_ZBOOT_ROM_TEXT)
ZBSSADDR := $(CONFIG_ZBOOT_ROM_BSS)
else
ZTEXTADDR := 0
ZBSSADDR := ALIGN(8)
endif
SEDFLAGS = s/TEXT_START/$(ZTEXTADDR)/;s/BSS_START/$(ZBSSADDR)/
suffix_$(CONFIG_KERNEL_GZIP) = gzip
suffix_$(CONFIG_KERNEL_LZO) = lzo
suffix_$(CONFIG_KERNEL_LZMA) = lzma
targets := vmlinux vmlinux.lds \
piggy.$(suffix_y) piggy.$(suffix_y).o \
font.o font.c head.o misc.o $(OBJS)
# Make sure files are removed during clean
extra-y += piggy.gzip piggy.lzo piggy.lzma lib1funcs.S
ifeq ($(CONFIG_FUNCTION_TRACER),y)
ORIG_CFLAGS := $(KBUILD_CFLAGS)
KBUILD_CFLAGS = $(subst -pg, , $(ORIG_CFLAGS))
endif
ccflags-y := -fpic -fno-builtin
asflags-y := -Wa,-march=all
# Supply kernel BSS size to the decompressor via a linker symbol.
KBSS_SZ = $(shell size $(obj)/../../../../vmlinux | awk 'END{print $$3}')
LDFLAGS_vmlinux = --defsym _kernel_bss_size=$(KBSS_SZ)
# Supply ZRELADDR to the decompressor via a linker symbol.
ifneq ($(CONFIG_AUTO_ZRELADDR),y)
LDFLAGS_vmlinux += --defsym zreladdr=$(ZRELADDR)
endif
ifeq ($(CONFIG_CPU_ENDIAN_BE8),y)
LDFLAGS_vmlinux += --be8
endif
# ?
LDFLAGS_vmlinux += -p
# Report unresolved symbol references
LDFLAGS_vmlinux += --no-undefined
# Delete all temporary local symbols
LDFLAGS_vmlinux += -X
# Next argument is a linker script
LDFLAGS_vmlinux += -T
# For __aeabi_uidivmod
lib1funcs = $(obj)/lib1funcs.o
$(obj)/lib1funcs.S: $(srctree)/arch/$(SRCARCH)/lib/lib1funcs.S FORCE
$(call cmd,shipped)
# We need to prevent any GOTOFF relocs being used with references
# to symbols in the .bss section since we cannot relocate them
# independently from the rest at run time. This can be achieved by
# ensuring that no private .bss symbols exist, as global symbols
# always have a GOT entry which is what we need.
# The .data section is already discarded by the linker script so no need
# to bother about it here.
check_for_bad_syms = \
bad_syms=$$($(CROSS_COMPILE)nm $@ | sed -n 's/^.\{8\} [bc] \(.*\)/\1/p') && \
[ -z "$$bad_syms" ] || \
( echo "following symbols must have non local/private scope:" >&2; \
echo "$$bad_syms" >&2; rm -f $@; false )
$(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/$(HEAD) $(obj)/piggy.$(suffix_y).o \
$(addprefix $(obj)/, $(OBJS)) $(lib1funcs) FORCE
$(call if_changed,ld)
@$(check_for_bad_syms)
$(obj)/piggy.$(suffix_y): $(obj)/../Image FORCE
$(call if_changed,$(suffix_y))
$(obj)/piggy.$(suffix_y).o: $(obj)/piggy.$(suffix_y) FORCE
CFLAGS_font.o := -Dstatic=
$(obj)/font.c: $(FONTC)
$(call cmd,shipped)
$(obj)/vmlinux.lds: $(obj)/vmlinux.lds.in arch/arm/boot/Makefile $(KCONFIG_CONFIG)
@sed "$(SEDFLAGS)" < $< > $@