alistair23-linux/arch/powerpc/Makefile
Paul Mackerras 549e8152de powerpc: Make the 64-bit kernel as a position-independent executable
This implements CONFIG_RELOCATABLE for 64-bit by making the kernel as
a position-independent executable (PIE) when it is set.  This involves
processing the dynamic relocations in the image in the early stages of
booting, even if the kernel is being run at the address it is linked at,
since the linker does not necessarily fill in words in the image for
which there are dynamic relocations.  (In fact the linker does fill in
such words for 64-bit executables, though not for 32-bit executables,
so in principle we could avoid calling relocate() entirely when we're
running a 64-bit kernel at the linked address.)

The dynamic relocations are processed by a new function relocate(addr),
where the addr parameter is the virtual address where the image will be
run.  In fact we call it twice; once before calling prom_init, and again
when starting the main kernel.  This means that reloc_offset() returns
0 in prom_init (since it has been relocated to the address it is running
at), which necessitated a few adjustments.

This also changes __va and __pa to use an equivalent definition that is
simpler.  With the relocatable kernel, PAGE_OFFSET and MEMORY_START are
constants (for 64-bit) whereas PHYSICAL_START is a variable (and
KERNELBASE ideally should be too, but isn't yet).

With this, relocatable kernels still copy themselves down to physical
address 0 and run there.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-15 11:08:38 -07:00

241 lines
7.5 KiB
Makefile

# This file is included by the global makefile so that you can add your own
# architecture-specific flags and dependencies. Remember to do have actions
# for "archclean" and "archdep" for cleaning up and making dependencies for
# this architecture.
#
# 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) 1994 by Linus Torvalds
# Changes for PPC by Gary Thomas
# Rewritten by Cort Dougan and Paul Mackerras
#
HAS_BIARCH := $(call cc-option-yn, -m32)
# Set default 32 bits cross compilers for vdso and boot wrapper
CROSS32_COMPILE ?=
CROSS32CC := $(CROSS32_COMPILE)gcc
CROSS32AR := $(CROSS32_COMPILE)ar
ifeq ($(HAS_BIARCH),y)
ifeq ($(CROSS32_COMPILE),)
CROSS32CC := $(CC) -m32
CROSS32AR := GNUTARGET=elf32-powerpc $(AR)
endif
endif
export CROSS32CC CROSS32AR
ifeq ($(CROSS_COMPILE),)
KBUILD_DEFCONFIG := $(shell uname -m)_defconfig
else
KBUILD_DEFCONFIG := ppc64_defconfig
endif
ifeq ($(CONFIG_PPC64),y)
OLDARCH := ppc64
new_nm := $(shell if $(NM) --help 2>&1 | grep -- '--synthetic' > /dev/null; then echo y; else echo n; fi)
ifeq ($(new_nm),y)
NM := $(NM) --synthetic
endif
else
OLDARCH := ppc
endif
# It seems there are times we use this Makefile without
# including the config file, but this replicates the old behaviour
ifeq ($(CONFIG_WORD_SIZE),)
CONFIG_WORD_SIZE := 32
endif
UTS_MACHINE := $(OLDARCH)
ifeq ($(HAS_BIARCH),y)
override AS += -a$(CONFIG_WORD_SIZE)
override LD += -m elf$(CONFIG_WORD_SIZE)ppc
override CC += -m$(CONFIG_WORD_SIZE)
override AR := GNUTARGET=elf$(CONFIG_WORD_SIZE)-powerpc $(AR)
endif
LDFLAGS_vmlinux-yy := -Bstatic
LDFLAGS_vmlinux-$(CONFIG_PPC64)$(CONFIG_RELOCATABLE) := -pie
LDFLAGS_vmlinux := $(LDFLAGS_vmlinux-yy)
CFLAGS-$(CONFIG_PPC64) := -mminimal-toc -mtraceback=none -mcall-aixdesc
CFLAGS-$(CONFIG_PPC32) := -ffixed-r2 -mmultiple
KBUILD_CPPFLAGS += -Iarch/$(ARCH)
KBUILD_AFLAGS += -Iarch/$(ARCH)
KBUILD_CFLAGS += -msoft-float -pipe -Iarch/$(ARCH) $(CFLAGS-y)
CPP = $(CC) -E $(KBUILD_CFLAGS)
CHECKFLAGS += -m$(CONFIG_WORD_SIZE) -D__powerpc__ -D__powerpc$(CONFIG_WORD_SIZE)__
ifeq ($(CONFIG_PPC64),y)
GCC_BROKEN_VEC := $(shell if [ $(call cc-version) -lt 0400 ] ; then echo "y"; fi)
ifeq ($(CONFIG_POWER4_ONLY),y)
ifeq ($(CONFIG_ALTIVEC),y)
ifeq ($(GCC_BROKEN_VEC),y)
KBUILD_CFLAGS += $(call cc-option,-mcpu=970)
else
KBUILD_CFLAGS += $(call cc-option,-mcpu=power4)
endif
else
KBUILD_CFLAGS += $(call cc-option,-mcpu=power4)
endif
else
KBUILD_CFLAGS += $(call cc-option,-mtune=power4)
endif
else
LDFLAGS_MODULE += arch/powerpc/lib/crtsavres.o
endif
ifeq ($(CONFIG_TUNE_CELL),y)
KBUILD_CFLAGS += $(call cc-option,-mtune=cell)
endif
# No AltiVec instruction when building kernel
KBUILD_CFLAGS += $(call cc-option,-mno-altivec)
# No SPE instruction when building kernel
KBUILD_CFLAGS += $(call cc-option,-mno-spe)
# Enable unit-at-a-time mode when possible. It shrinks the
# kernel considerably.
KBUILD_CFLAGS += $(call cc-option,-funit-at-a-time)
# Never use string load/store instructions as they are
# often slow when they are implemented at all
KBUILD_CFLAGS += -mno-string
ifeq ($(CONFIG_6xx),y)
KBUILD_CFLAGS += -mcpu=powerpc
endif
# Work around a gcc code-gen bug with -fno-omit-frame-pointer.
ifeq ($(CONFIG_FTRACE),y)
KBUILD_CFLAGS += -mno-sched-epilog
endif
cpu-as-$(CONFIG_4xx) += -Wa,-m405
cpu-as-$(CONFIG_6xx) += -Wa,-maltivec
cpu-as-$(CONFIG_POWER4) += -Wa,-maltivec
cpu-as-$(CONFIG_E500) += -Wa,-me500
cpu-as-$(CONFIG_E200) += -Wa,-me200
KBUILD_AFLAGS += $(cpu-as-y)
KBUILD_CFLAGS += $(cpu-as-y)
head-y := arch/powerpc/kernel/head_$(CONFIG_WORD_SIZE).o
head-$(CONFIG_8xx) := arch/powerpc/kernel/head_8xx.o
head-$(CONFIG_40x) := arch/powerpc/kernel/head_40x.o
head-$(CONFIG_44x) := arch/powerpc/kernel/head_44x.o
head-$(CONFIG_FSL_BOOKE) := arch/powerpc/kernel/head_fsl_booke.o
head-$(CONFIG_PPC64) += arch/powerpc/kernel/entry_64.o
head-$(CONFIG_PPC_FPU) += arch/powerpc/kernel/fpu.o
core-y += arch/powerpc/kernel/ \
arch/powerpc/mm/ \
arch/powerpc/lib/ \
arch/powerpc/sysdev/ \
arch/powerpc/platforms/
core-$(CONFIG_MATH_EMULATION) += arch/powerpc/math-emu/
core-$(CONFIG_XMON) += arch/powerpc/xmon/
core-$(CONFIG_KVM) += arch/powerpc/kvm/
drivers-$(CONFIG_OPROFILE) += arch/powerpc/oprofile/
# Default to zImage, override when needed
all: zImage
CPPFLAGS_vmlinux.lds := -Upowerpc
BOOT_TARGETS = zImage zImage.initrd uImage zImage% dtbImage% treeImage.% cuImage.% simpleImage.%
PHONY += $(BOOT_TARGETS)
boot := arch/$(ARCH)/boot
$(BOOT_TARGETS): vmlinux
$(Q)$(MAKE) ARCH=ppc64 $(build)=$(boot) $(patsubst %,$(boot)/%,$@)
bootwrapper_install %.dtb:
$(Q)$(MAKE) ARCH=ppc64 $(build)=$(boot) $(patsubst %,$(boot)/%,$@)
define archhelp
@echo '* zImage - Build default images selected by kernel config'
@echo ' zImage.* - Compressed kernel image (arch/$(ARCH)/boot/zImage.*)'
@echo ' uImage - U-Boot native image format'
@echo ' cuImage.<dt> - Backwards compatible U-Boot image for older'
@echo ' versions which do not support device trees'
@echo ' dtbImage.<dt> - zImage with an embedded device tree blob'
@echo ' simpleImage.<dt> - Firmware independent image.'
@echo ' treeImage.<dt> - Support for older IBM 4xx firmware (not U-Boot)'
@echo ' install - Install kernel using'
@echo ' (your) ~/bin/installkernel or'
@echo ' (distribution) /sbin/installkernel or'
@echo ' install to $$(INSTALL_PATH) and run lilo'
@echo ' *_defconfig - Select default config from arch/$(ARCH)/configs'
@echo ''
@echo ' Targets with <dt> embed a device tree blob inside the image'
@echo ' These targets support board with firmware that does not'
@echo ' support passing a device tree directly. Replace <dt> with the'
@echo ' name of a dts file from the arch/$(ARCH)/boot/dts/ directory'
@echo ' (minus the .dts extension).'
endef
install:
$(Q)$(MAKE) $(build)=$(boot) install
vdso_install:
ifeq ($(CONFIG_PPC64),y)
$(Q)$(MAKE) $(build)=arch/$(ARCH)/kernel/vdso64 $@
endif
$(Q)$(MAKE) $(build)=arch/$(ARCH)/kernel/vdso32 $@
archclean:
$(Q)$(MAKE) $(clean)=$(boot)
archprepare: checkbin
# Use the file '.tmp_gas_check' for binutils tests, as gas won't output
# to stdout and these checks are run even on install targets.
TOUT := .tmp_gas_check
# Ensure this is binutils 2.12.1 (or 2.12.90.0.7) or later for altivec
# instructions.
# gcc-3.4 and binutils-2.14 are a fatal combination.
checkbin:
@if test "$(call cc-version)" = "0304" ; then \
if ! /bin/echo mftb 5 | $(AS) -v -mppc -many -o $(TOUT) >/dev/null 2>&1 ; then \
echo -n '*** ${VERSION}.${PATCHLEVEL} kernels no longer build '; \
echo 'correctly with gcc-3.4 and your version of binutils.'; \
echo '*** Please upgrade your binutils or downgrade your gcc'; \
false; \
fi ; \
fi
@if test "$(call cc-fullversion)" = "040200" \
&& test "x${CONFIG_MODULES}${CONFIG_PPC64}" = "xyy" ; then \
echo -n '*** GCC-4.2.0 cannot compile the 64-bit powerpc ' ; \
echo 'kernel with modules enabled.' ; \
echo -n '*** Please use a different GCC version or ' ; \
echo 'disable kernel modules' ; \
false ; \
fi
@if ! /bin/echo dssall | $(AS) -many -o $(TOUT) >/dev/null 2>&1 ; then \
echo -n '*** ${VERSION}.${PATCHLEVEL} kernels no longer build ' ; \
echo 'correctly with old versions of binutils.' ; \
echo '*** Please upgrade your binutils to 2.12.1 or newer' ; \
false ; \
fi
CLEAN_FILES += $(TOUT)