android_kernel_xiaomi_sm8350/arch/arm/boot/Makefile
Dave Martin 26e5ca93dd ARM: 6503/1: Thumb-2: Restore sensible zImage header layout for CONFIG_THUMB2_KERNEL
The code which makes up the zImage header intends to leave a
32-byte gap followed by a branch to the real entry point, a magic
number, and a word containing the absolute entry point address.

This gets messed up with with CONFIG_THUMB2_KERNEL, because the
size of the initial padding NOPs changes.

Instead, the header can be made fully compatible by restoring it to
ARM.

In the Thumb-2 case, we can replace the initial NOPs with a
sequence which switches to Thumb and jumps to the real entry point.

As a consequence, the zImage entry point is now always ARM, so no
special magic is needed any more for the uImage rules in the
Thumb-2 case.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-11-30 13:44:26 +00:00

111 lines
2.9 KiB
Makefile

#
# arch/arm/boot/Makefile
#
# This file is included by the global makefile so that you can add your own
# architecture-specific flags and dependencies.
#
# This file is subject to the terms and conditions of the GNU General Public
# License. See the file "COPYING" in the main directory of this archive
# for more details.
#
# Copyright (C) 1995-2002 Russell King
#
MKIMAGE := $(srctree)/scripts/mkuboot.sh
ifneq ($(MACHINE),)
include $(srctree)/$(MACHINE)/Makefile.boot
endif
# Note: the following conditions must always be true:
# ZRELADDR == virt_to_phys(PAGE_OFFSET + TEXT_OFFSET)
# PARAMS_PHYS must be within 4MB of ZRELADDR
# INITRD_PHYS must be in RAM
ZRELADDR := $(zreladdr-y)
PARAMS_PHYS := $(params_phys-y)
INITRD_PHYS := $(initrd_phys-y)
export ZRELADDR INITRD_PHYS PARAMS_PHYS
targets := Image zImage xipImage bootpImage uImage
ifeq ($(CONFIG_XIP_KERNEL),y)
$(obj)/xipImage: vmlinux FORCE
$(call if_changed,objcopy)
@echo ' Kernel: $@ is ready (physical address: $(CONFIG_XIP_PHYS_ADDR))'
$(obj)/Image $(obj)/zImage: FORCE
@echo 'Kernel configured for XIP (CONFIG_XIP_KERNEL=y)'
@echo 'Only the xipImage target is available in this case'
@false
else
$(obj)/xipImage: FORCE
@echo 'Kernel not configured for XIP (CONFIG_XIP_KERNEL!=y)'
@false
$(obj)/Image: vmlinux FORCE
$(call if_changed,objcopy)
@echo ' Kernel: $@ is ready'
$(obj)/compressed/vmlinux: $(obj)/Image FORCE
$(Q)$(MAKE) $(build)=$(obj)/compressed $@
$(obj)/zImage: $(obj)/compressed/vmlinux FORCE
$(call if_changed,objcopy)
@echo ' Kernel: $@ is ready'
endif
quiet_cmd_uimage = UIMAGE $@
cmd_uimage = $(CONFIG_SHELL) $(MKIMAGE) -A arm -O linux -T kernel \
-C none -a $(LOADADDR) -e $(STARTADDR) \
-n 'Linux-$(KERNELRELEASE)' -d $< $@
ifeq ($(CONFIG_ZBOOT_ROM),y)
$(obj)/uImage: LOADADDR=$(CONFIG_ZBOOT_ROM_TEXT)
else
$(obj)/uImage: LOADADDR=$(ZRELADDR)
endif
$(obj)/uImage: STARTADDR=$(LOADADDR)
$(obj)/uImage: $(obj)/zImage FORCE
$(call if_changed,uimage)
@echo ' Image $@ is ready'
$(obj)/bootp/bootp: $(obj)/zImage initrd FORCE
$(Q)$(MAKE) $(build)=$(obj)/bootp $@
@:
$(obj)/bootpImage: $(obj)/bootp/bootp FORCE
$(call if_changed,objcopy)
@echo ' Kernel: $@ is ready'
PHONY += initrd FORCE
initrd:
@test "$(INITRD_PHYS)" != "" || \
(echo This machine does not support INITRD; exit -1)
@test "$(INITRD)" != "" || \
(echo You must specify INITRD; exit -1)
install: $(obj)/Image
$(CONFIG_SHELL) $(srctree)/$(src)/install.sh $(KERNELRELEASE) \
$(obj)/Image System.map "$(INSTALL_PATH)"
zinstall: $(obj)/zImage
$(CONFIG_SHELL) $(srctree)/$(src)/install.sh $(KERNELRELEASE) \
$(obj)/zImage System.map "$(INSTALL_PATH)"
zi:
$(CONFIG_SHELL) $(srctree)/$(src)/install.sh $(KERNELRELEASE) \
$(obj)/zImage System.map "$(INSTALL_PATH)"
i:
$(CONFIG_SHELL) $(srctree)/$(src)/install.sh $(KERNELRELEASE) \
$(obj)/Image System.map "$(INSTALL_PATH)"
subdir- := bootp compressed