linux/arch/arm/Makefile
Ard Biesheuvel 02e541db05 ARM: 8323/1: force linker to use PIC veneers
When building a very large kernel, it is up to the linker to decide
when and where to insert stubs to allow calls to functions that are
out of range for the ordinary b/bl instructions.

However, since the kernel is built as a position dependent binary,
these stubs (aka veneers) may contain absolute addresses, which will
break far calls performed with the MMU off.

For instance, the call from __enable_mmu() in the .head.text section
to __turn_mmu_on() in the .idmap.text section may be turned into
something like this:

c0008168 <__enable_mmu>:
c0008168:       f020 0002       bic.w   r0, r0, #2
c000816c:       f420 5080       bic.w   r0, r0, #4096
c0008170:       f000 b846       b.w     c0008200 <____turn_mmu_on_veneer>
[...]
c0008200 <____turn_mmu_on_veneer>:
c0008200:       4778            bx      pc
c0008202:       46c0            nop
c0008204:       e59fc000        ldr     ip, [pc]
c0008208:       e12fff1c        bx      ip
c000820c:       c13dfae1        teqgt   sp, r1, ror #21
[...]
c13dfae0 <__turn_mmu_on>:
c13dfae0:       4600            mov     r0, r0
[...]

After adding --pic-veneer to the LDFLAGS, the veneer is emitted like
this instead:

c0008200 <____turn_mmu_on_veneer>:
c0008200:       4778            bx      pc
c0008202:       46c0            nop
c0008204:       e59fc004        ldr     ip, [pc, #4]
c0008208:       e08fc00c        add     ip, pc, ip
c000820c:       e12fff1c        bx      ip
c0008210:       013d7d31        teqeq   sp, r1, lsr sp
c0008214:       00000000        andeq   r0, r0, r0

Note that this particular example is best addressed by moving
.head.text and .idmap.text closer together, but this issue could
potentially affect any code that needs to execute with the
MMU off.

Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-03-29 23:11:56 +01:00

348 lines
12 KiB
Makefile

#
# arch/arm/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) 1995-2001 by Russell King
# Ensure linker flags are correct
LDFLAGS :=
LDFLAGS_vmlinux :=-p --no-undefined -X --pic-veneer
ifeq ($(CONFIG_CPU_ENDIAN_BE8),y)
LDFLAGS_vmlinux += --be8
LDFLAGS_MODULE += --be8
endif
OBJCOPYFLAGS :=-O binary -R .comment -S
GZFLAGS :=-9
#KBUILD_CFLAGS +=-pipe
# Never generate .eh_frame
KBUILD_CFLAGS += $(call cc-option,-fno-dwarf2-cfi-asm)
# Do not use arch/arm/defconfig - it's always outdated.
# Select a platform tht is kept up-to-date
KBUILD_DEFCONFIG := versatile_defconfig
# defines filename extension depending memory management type.
ifeq ($(CONFIG_MMU),)
MMUEXT := -nommu
KBUILD_CFLAGS += $(call cc-option,-mno-unaligned-access)
endif
ifeq ($(CONFIG_FRAME_POINTER),y)
KBUILD_CFLAGS +=-fno-omit-frame-pointer -mapcs -mno-sched-prolog
endif
ifeq ($(CONFIG_CPU_BIG_ENDIAN),y)
KBUILD_CPPFLAGS += -mbig-endian
AS += -EB
LD += -EB
else
KBUILD_CPPFLAGS += -mlittle-endian
AS += -EL
LD += -EL
endif
# This selects which instruction set is used.
# Note that GCC does not numerically define an architecture version
# macro, but instead defines a whole series of macros which makes
# testing for a specific architecture or later rather impossible.
arch-$(CONFIG_CPU_32v7M) =-D__LINUX_ARM_ARCH__=7 -march=armv7-m -Wa,-march=armv7-m
arch-$(CONFIG_CPU_32v7) =-D__LINUX_ARM_ARCH__=7 $(call cc-option,-march=armv7-a,-march=armv5t -Wa$(comma)-march=armv7-a)
arch-$(CONFIG_CPU_32v6) =-D__LINUX_ARM_ARCH__=6 $(call cc-option,-march=armv6,-march=armv5t -Wa$(comma)-march=armv6)
# Only override the compiler option if ARMv6. The ARMv6K extensions are
# always available in ARMv7
ifeq ($(CONFIG_CPU_32v6),y)
arch-$(CONFIG_CPU_32v6K) =-D__LINUX_ARM_ARCH__=6 $(call cc-option,-march=armv6k,-march=armv5t -Wa$(comma)-march=armv6k)
endif
arch-$(CONFIG_CPU_32v5) =-D__LINUX_ARM_ARCH__=5 $(call cc-option,-march=armv5te,-march=armv4t)
arch-$(CONFIG_CPU_32v4T) =-D__LINUX_ARM_ARCH__=4 -march=armv4t
arch-$(CONFIG_CPU_32v4) =-D__LINUX_ARM_ARCH__=4 -march=armv4
arch-$(CONFIG_CPU_32v3) =-D__LINUX_ARM_ARCH__=3 -march=armv3
# Evaluate arch cc-option calls now
arch-y := $(arch-y)
# This selects how we optimise for the processor.
tune-$(CONFIG_CPU_ARM7TDMI) =-mtune=arm7tdmi
tune-$(CONFIG_CPU_ARM720T) =-mtune=arm7tdmi
tune-$(CONFIG_CPU_ARM740T) =-mtune=arm7tdmi
tune-$(CONFIG_CPU_ARM9TDMI) =-mtune=arm9tdmi
tune-$(CONFIG_CPU_ARM940T) =-mtune=arm9tdmi
tune-$(CONFIG_CPU_ARM946E) =$(call cc-option,-mtune=arm9e,-mtune=arm9tdmi)
tune-$(CONFIG_CPU_ARM920T) =-mtune=arm9tdmi
tune-$(CONFIG_CPU_ARM922T) =-mtune=arm9tdmi
tune-$(CONFIG_CPU_ARM925T) =-mtune=arm9tdmi
tune-$(CONFIG_CPU_ARM926T) =-mtune=arm9tdmi
tune-$(CONFIG_CPU_FA526) =-mtune=arm9tdmi
tune-$(CONFIG_CPU_SA110) =-mtune=strongarm110
tune-$(CONFIG_CPU_SA1100) =-mtune=strongarm1100
tune-$(CONFIG_CPU_XSCALE) =$(call cc-option,-mtune=xscale,-mtune=strongarm110) -Wa,-mcpu=xscale
tune-$(CONFIG_CPU_XSC3) =$(call cc-option,-mtune=xscale,-mtune=strongarm110) -Wa,-mcpu=xscale
tune-$(CONFIG_CPU_FEROCEON) =$(call cc-option,-mtune=marvell-f,-mtune=xscale)
tune-$(CONFIG_CPU_V6) =$(call cc-option,-mtune=arm1136j-s,-mtune=strongarm)
tune-$(CONFIG_CPU_V6K) =$(call cc-option,-mtune=arm1136j-s,-mtune=strongarm)
# Evaluate tune cc-option calls now
tune-y := $(tune-y)
ifeq ($(CONFIG_AEABI),y)
CFLAGS_ABI :=-mabi=aapcs-linux -mno-thumb-interwork -mfpu=vfp
else
CFLAGS_ABI :=$(call cc-option,-mapcs-32,-mabi=apcs-gnu) $(call cc-option,-mno-thumb-interwork,)
endif
ifeq ($(CONFIG_ARM_UNWIND),y)
CFLAGS_ABI +=-funwind-tables
endif
ifeq ($(CONFIG_THUMB2_KERNEL),y)
AFLAGS_AUTOIT :=$(call as-option,-Wa$(comma)-mimplicit-it=always,-Wa$(comma)-mauto-it)
AFLAGS_NOWARN :=$(call as-option,-Wa$(comma)-mno-warn-deprecated,-Wa$(comma)-W)
CFLAGS_ISA :=-mthumb $(AFLAGS_AUTOIT) $(AFLAGS_NOWARN)
AFLAGS_ISA :=$(CFLAGS_ISA) -Wa$(comma)-mthumb
# Work around buggy relocation from gas if requested:
ifeq ($(CONFIG_THUMB2_AVOID_R_ARM_THM_JUMP11),y)
CFLAGS_MODULE +=-fno-optimize-sibling-calls
endif
else
CFLAGS_ISA :=$(call cc-option,-marm,)
AFLAGS_ISA :=$(CFLAGS_ISA)
endif
# Need -Uarm for gcc < 3.x
KBUILD_CFLAGS +=$(CFLAGS_ABI) $(CFLAGS_ISA) $(arch-y) $(tune-y) $(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,)) -msoft-float -Uarm
KBUILD_AFLAGS +=$(CFLAGS_ABI) $(AFLAGS_ISA) $(arch-y) $(tune-y) -include asm/unified.h -msoft-float
CHECKFLAGS += -D__arm__
#Default value
head-y := arch/arm/kernel/head$(MMUEXT).o
# Text offset. This list is sorted numerically by address in order to
# provide a means to avoid/resolve conflicts in multi-arch kernels.
textofs-y := 0x00008000
textofs-$(CONFIG_ARCH_CLPS711X) := 0x00028000
# We don't want the htc bootloader to corrupt kernel during resume
textofs-$(CONFIG_PM_H1940) := 0x00108000
# SA1111 DMA bug: we don't want the kernel to live in precious DMA-able memory
ifeq ($(CONFIG_ARCH_SA1100),y)
textofs-$(CONFIG_SA1111) := 0x00208000
endif
textofs-$(CONFIG_ARCH_MSM7X30) := 0x00208000
textofs-$(CONFIG_ARCH_MSM8X60) := 0x00208000
textofs-$(CONFIG_ARCH_MSM8960) := 0x00208000
textofs-$(CONFIG_ARCH_AXXIA) := 0x00308000
# Machine directory name. This list is sorted alphanumerically
# by CONFIG_* macro name.
machine-$(CONFIG_ARCH_AT91) += at91
machine-$(CONFIG_ARCH_AXXIA) += axxia
machine-$(CONFIG_ARCH_BCM) += bcm
machine-$(CONFIG_ARCH_BERLIN) += berlin
machine-$(CONFIG_ARCH_CLPS711X) += clps711x
machine-$(CONFIG_ARCH_CNS3XXX) += cns3xxx
machine-$(CONFIG_ARCH_DAVINCI) += davinci
machine-$(CONFIG_ARCH_DOVE) += dove
machine-$(CONFIG_ARCH_EBSA110) += ebsa110
machine-$(CONFIG_ARCH_EFM32) += efm32
machine-$(CONFIG_ARCH_EP93XX) += ep93xx
machine-$(CONFIG_ARCH_EXYNOS) += exynos
machine-$(CONFIG_ARCH_FOOTBRIDGE) += footbridge
machine-$(CONFIG_ARCH_GEMINI) += gemini
machine-$(CONFIG_ARCH_HIGHBANK) += highbank
machine-$(CONFIG_ARCH_HISI) += hisi
machine-$(CONFIG_ARCH_INTEGRATOR) += integrator
machine-$(CONFIG_ARCH_IOP13XX) += iop13xx
machine-$(CONFIG_ARCH_IOP32X) += iop32x
machine-$(CONFIG_ARCH_IOP33X) += iop33x
machine-$(CONFIG_ARCH_IXP4XX) += ixp4xx
machine-$(CONFIG_ARCH_KEYSTONE) += keystone
machine-$(CONFIG_ARCH_KS8695) += ks8695
machine-$(CONFIG_ARCH_LPC32XX) += lpc32xx
machine-$(CONFIG_ARCH_MESON) += meson
machine-$(CONFIG_ARCH_MMP) += mmp
machine-$(CONFIG_ARCH_MOXART) += moxart
machine-$(CONFIG_ARCH_MSM) += msm
machine-$(CONFIG_ARCH_MV78XX0) += mv78xx0
machine-$(CONFIG_ARCH_MVEBU) += mvebu
machine-$(CONFIG_ARCH_MXC) += imx
machine-$(CONFIG_ARCH_MEDIATEK) += mediatek
machine-$(CONFIG_ARCH_MXS) += mxs
machine-$(CONFIG_ARCH_NETX) += netx
machine-$(CONFIG_ARCH_NOMADIK) += nomadik
machine-$(CONFIG_ARCH_NSPIRE) += nspire
machine-$(CONFIG_ARCH_OMAP1) += omap1
machine-$(CONFIG_ARCH_OMAP2PLUS) += omap2
machine-$(CONFIG_ARCH_ORION5X) += orion5x
machine-$(CONFIG_ARCH_PICOXCELL) += picoxcell
machine-$(CONFIG_ARCH_PXA) += pxa
machine-$(CONFIG_ARCH_QCOM) += qcom
machine-$(CONFIG_ARCH_REALVIEW) += realview
machine-$(CONFIG_ARCH_ROCKCHIP) += rockchip
machine-$(CONFIG_ARCH_RPC) += rpc
machine-$(CONFIG_ARCH_S3C24XX) += s3c24xx
machine-$(CONFIG_ARCH_S3C64XX) += s3c64xx
machine-$(CONFIG_ARCH_S5PV210) += s5pv210
machine-$(CONFIG_ARCH_SA1100) += sa1100
machine-$(CONFIG_ARCH_SHMOBILE) += shmobile
machine-$(CONFIG_ARCH_SIRF) += prima2
machine-$(CONFIG_ARCH_SOCFPGA) += socfpga
machine-$(CONFIG_ARCH_STI) += sti
machine-$(CONFIG_ARCH_SUNXI) += sunxi
machine-$(CONFIG_ARCH_TEGRA) += tegra
machine-$(CONFIG_ARCH_U300) += u300
machine-$(CONFIG_ARCH_U8500) += ux500
machine-$(CONFIG_ARCH_VERSATILE) += versatile
machine-$(CONFIG_ARCH_VEXPRESS) += vexpress
machine-$(CONFIG_ARCH_VT8500) += vt8500
machine-$(CONFIG_ARCH_W90X900) += w90x900
machine-$(CONFIG_ARCH_ZYNQ) += zynq
machine-$(CONFIG_PLAT_SPEAR) += spear
# Platform directory name. This list is sorted alphanumerically
# by CONFIG_* macro name.
plat-$(CONFIG_ARCH_EXYNOS) += samsung
plat-$(CONFIG_ARCH_OMAP) += omap
plat-$(CONFIG_ARCH_S3C64XX) += samsung
plat-$(CONFIG_ARCH_S5PV210) += samsung
plat-$(CONFIG_PLAT_IOP) += iop
plat-$(CONFIG_PLAT_ORION) += orion
plat-$(CONFIG_PLAT_PXA) += pxa
plat-$(CONFIG_PLAT_S3C24XX) += samsung
plat-$(CONFIG_PLAT_VERSATILE) += versatile
ifeq ($(CONFIG_ARCH_EBSA110),y)
# This is what happens if you forget the IOCS16 line.
# PCMCIA cards stop working.
CFLAGS_3c589_cs.o :=-DISA_SIXTEEN_BIT_PERIPHERAL
export CFLAGS_3c589_cs.o
endif
# The byte offset of the kernel image in RAM from the start of RAM.
TEXT_OFFSET := $(textofs-y)
# The first directory contains additional information for the boot setup code
ifneq ($(machine-y),)
MACHINE := arch/arm/mach-$(word 1,$(machine-y))/
else
MACHINE :=
endif
ifeq ($(CONFIG_ARCH_MULTIPLATFORM),y)
MACHINE :=
endif
machdirs := $(patsubst %,arch/arm/mach-%/,$(machine-y))
platdirs := $(patsubst %,arch/arm/plat-%/,$(sort $(plat-y)))
ifneq ($(CONFIG_ARCH_MULTIPLATFORM),y)
ifeq ($(KBUILD_SRC),)
KBUILD_CPPFLAGS += $(patsubst %,-I%include,$(machdirs) $(platdirs))
else
KBUILD_CPPFLAGS += $(patsubst %,-I$(srctree)/%include,$(machdirs) $(platdirs))
endif
endif
export TEXT_OFFSET GZFLAGS MMUEXT
# Do we have FASTFPE?
FASTFPE :=arch/arm/fastfpe
ifeq ($(FASTFPE),$(wildcard $(FASTFPE)))
FASTFPE_OBJ :=$(FASTFPE)/
endif
core-$(CONFIG_FPE_NWFPE) += arch/arm/nwfpe/
core-$(CONFIG_FPE_FASTFPE) += $(FASTFPE_OBJ)
core-$(CONFIG_VFP) += arch/arm/vfp/
core-$(CONFIG_XEN) += arch/arm/xen/
core-$(CONFIG_KVM_ARM_HOST) += arch/arm/kvm/
# If we have a machine-specific directory, then include it in the build.
core-y += arch/arm/kernel/ arch/arm/mm/ arch/arm/common/
core-y += arch/arm/probes/
core-y += arch/arm/net/
core-y += arch/arm/crypto/
core-y += arch/arm/firmware/
core-y += $(machdirs) $(platdirs)
drivers-$(CONFIG_OPROFILE) += arch/arm/oprofile/
libs-y := arch/arm/lib/ $(libs-y)
# Default target when executing plain make
ifeq ($(CONFIG_XIP_KERNEL),y)
KBUILD_IMAGE := xipImage
else
KBUILD_IMAGE := zImage
endif
# Build the DT binary blobs if we have OF configured
ifeq ($(CONFIG_USE_OF),y)
KBUILD_DTBS := dtbs
endif
all: $(KBUILD_IMAGE) $(KBUILD_DTBS)
boot := arch/arm/boot
archprepare:
$(Q)$(MAKE) $(build)=arch/arm/tools include/generated/mach-types.h
# Convert bzImage to zImage
bzImage: zImage
BOOT_TARGETS = zImage Image xipImage bootpImage uImage
INSTALL_TARGETS = zinstall uinstall install
PHONY += bzImage $(BOOT_TARGETS) $(INSTALL_TARGETS)
$(BOOT_TARGETS): vmlinux
$(Q)$(MAKE) $(build)=$(boot) MACHINE=$(MACHINE) $(boot)/$@
$(INSTALL_TARGETS):
$(Q)$(MAKE) $(build)=$(boot) MACHINE=$(MACHINE) $@
%.dtb: | scripts
$(Q)$(MAKE) $(build)=$(boot)/dts MACHINE=$(MACHINE) $(boot)/dts/$@
PHONY += dtbs dtbs_install
dtbs: prepare scripts
$(Q)$(MAKE) $(build)=$(boot)/dts
dtbs_install:
$(Q)$(MAKE) $(dtbinst)=$(boot)/dts
# We use MRPROPER_FILES and CLEAN_FILES now
archclean:
$(Q)$(MAKE) $(clean)=$(boot)
# My testing targets (bypasses dependencies)
bp:; $(Q)$(MAKE) $(build)=$(boot) MACHINE=$(MACHINE) $(boot)/bootpImage
i zi:; $(Q)$(MAKE) $(build)=$(boot) MACHINE=$(MACHINE) $@
define archhelp
echo '* zImage - Compressed kernel image (arch/$(ARCH)/boot/zImage)'
echo ' Image - Uncompressed kernel image (arch/$(ARCH)/boot/Image)'
echo '* xipImage - XIP kernel image, if configured (arch/$(ARCH)/boot/xipImage)'
echo ' uImage - U-Boot wrapped zImage'
echo ' bootpImage - Combined zImage and initial RAM disk'
echo ' (supply initrd image via make variable INITRD=<path>)'
echo '* dtbs - Build device tree blobs for enabled boards'
echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'
echo ' install - Install uncompressed kernel'
echo ' zinstall - Install compressed kernel'
echo ' uinstall - Install U-Boot wrapped compressed kernel'
echo ' Install using (your) ~/bin/$(INSTALLKERNEL) or'
echo ' (distribution) /sbin/$(INSTALLKERNEL) or'
echo ' install to $$(INSTALL_PATH) and run lilo'
endef