linux/arch/powerpc/kernel/Makefile
Anton Blanchard 5ac47f7a6e powerpc: Relocate prom_init.c on 64bit
The ppc64 kernel can get loaded at any address which means
our very early init code in prom_init.c must be relocatable. We do
this with a pretty nasty RELOC() macro that we wrap accesses of
variables with. It is very fragile and sometimes we forget to add a
RELOC() to an uncommon path or sometimes a compiler change breaks it.

32bit has a much more elegant solution where we build prom_init.c
with -mrelocatable and then process the relocations manually.
Unfortunately we can't do the equivalent on 64bit and we would
have to build the entire kernel relocatable (-pie), resulting in a
large increase in kernel footprint (megabytes of relocation data).
The relocation data will be marked __initdata but it still creates
more pressure on our already tight memory layout at boot.

Alan Modra pointed out that the 64bit ABI is relocatable even
if we don't build with -pie, we just need to relocate the TOC.
This patch implements that idea and relocates the TOC entries of
prom_init.c. An added bonus is there are very few relocations to
process which helps keep boot times on simulators down.

gcc does not put 64bit integer constants into the TOC but to be
safe we may want a build time script which passes through the
prom_init.c TOC entries to make sure everything looks reasonable.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-01-10 17:00:25 +11:00

168 lines
5.3 KiB
Makefile

#
# Makefile for the linux kernel.
#
CFLAGS_ptrace.o += -DUTS_MACHINE='"$(UTS_MACHINE)"'
subdir-ccflags-$(CONFIG_PPC_WERROR) := -Werror
ifeq ($(CONFIG_PPC64),y)
CFLAGS_prom_init.o += -mno-minimal-toc
endif
ifeq ($(CONFIG_PPC32),y)
CFLAGS_prom_init.o += -fPIC
CFLAGS_btext.o += -fPIC
endif
ifdef CONFIG_FUNCTION_TRACER
# Do not trace early boot code
CFLAGS_REMOVE_cputable.o = -pg -mno-sched-epilog
CFLAGS_REMOVE_prom_init.o = -pg -mno-sched-epilog
CFLAGS_REMOVE_btext.o = -pg -mno-sched-epilog
CFLAGS_REMOVE_prom.o = -pg -mno-sched-epilog
# do not trace tracer code
CFLAGS_REMOVE_ftrace.o = -pg -mno-sched-epilog
# timers used by tracing
CFLAGS_REMOVE_time.o = -pg -mno-sched-epilog
endif
obj-y := cputable.o ptrace.o syscalls.o \
irq.o align.o signal_32.o pmc.o vdso.o \
process.o systbl.o idle.o \
signal.o sysfs.o cacheinfo.o time.o \
prom.o traps.o setup-common.o \
udbg.o misc.o io.o dma.o \
misc_$(CONFIG_WORD_SIZE).o vdso32/
obj-$(CONFIG_PPC64) += setup_64.o sys_ppc32.o \
signal_64.o ptrace32.o \
paca.o nvram_64.o firmware.o
obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o
obj-$(CONFIG_PPC_BOOK3S_64) += cpu_setup_ppc970.o cpu_setup_pa6t.o
obj-$(CONFIG_PPC_BOOK3S_64) += cpu_setup_power.o
obj64-$(CONFIG_RELOCATABLE) += reloc_64.o
obj-$(CONFIG_PPC_BOOK3E_64) += exceptions-64e.o idle_book3e.o
obj-$(CONFIG_PPC_A2) += cpu_setup_a2.o
obj-$(CONFIG_PPC64) += vdso64/
obj-$(CONFIG_ALTIVEC) += vecemu.o
obj-$(CONFIG_PPC_970_NAP) += idle_power4.o
obj-$(CONFIG_PPC_P7_NAP) += idle_power7.o
obj-$(CONFIG_PPC_OF) += of_platform.o prom_parse.o
obj-$(CONFIG_PPC_CLOCK) += clock.o
procfs-y := proc_powerpc.o
obj-$(CONFIG_PROC_FS) += $(procfs-y)
rtaspci-$(CONFIG_PPC64)-$(CONFIG_PCI) := rtas_pci.o
obj-$(CONFIG_PPC_RTAS) += rtas.o rtas-rtc.o $(rtaspci-y-y)
obj-$(CONFIG_PPC_RTAS_DAEMON) += rtasd.o
obj-$(CONFIG_RTAS_FLASH) += rtas_flash.o
obj-$(CONFIG_RTAS_PROC) += rtas-proc.o
obj-$(CONFIG_LPARCFG) += lparcfg.o
obj-$(CONFIG_IBMVIO) += vio.o
obj-$(CONFIG_IBMEBUS) += ibmebus.o
obj-$(CONFIG_GENERIC_TBSYNC) += smp-tbsync.o
obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
obj-$(CONFIG_FA_DUMP) += fadump.o
ifeq ($(CONFIG_PPC32),y)
obj-$(CONFIG_E500) += idle_e500.o
endif
obj-$(CONFIG_6xx) += idle_6xx.o l2cr_6xx.o cpu_setup_6xx.o
obj-$(CONFIG_TAU) += tau_6xx.o
obj-$(CONFIG_HIBERNATION) += swsusp.o suspend.o
ifeq ($(CONFIG_FSL_BOOKE),y)
obj-$(CONFIG_HIBERNATION) += swsusp_booke.o
else
obj-$(CONFIG_HIBERNATION) += swsusp_$(CONFIG_WORD_SIZE).o
endif
obj64-$(CONFIG_HIBERNATION) += swsusp_asm64.o
obj-$(CONFIG_MODULES) += module.o module_$(CONFIG_WORD_SIZE).o
obj-$(CONFIG_44x) += cpu_setup_44x.o
obj-$(CONFIG_PPC_FSL_BOOK3E) += cpu_setup_fsl_booke.o
obj-$(CONFIG_PPC_DOORBELL) += dbell.o
obj-$(CONFIG_JUMP_LABEL) += jump_label.o
extra-y := head_$(CONFIG_WORD_SIZE).o
extra-$(CONFIG_40x) := head_40x.o
extra-$(CONFIG_44x) := head_44x.o
extra-$(CONFIG_FSL_BOOKE) := head_fsl_booke.o
extra-$(CONFIG_8xx) := head_8xx.o
extra-y += vmlinux.lds
obj-$(CONFIG_RELOCATABLE_PPC32) += reloc_32.o
obj-$(CONFIG_PPC32) += entry_32.o setup_32.o
obj-$(CONFIG_PPC64) += dma-iommu.o iommu.o
obj-$(CONFIG_KGDB) += kgdb.o
obj-$(CONFIG_MODULES) += ppc_ksyms.o
obj-$(CONFIG_BOOTX_TEXT) += btext.o
obj-$(CONFIG_SMP) += smp.o
obj-$(CONFIG_KPROBES) += kprobes.o
obj-$(CONFIG_UPROBES) += uprobes.o
obj-$(CONFIG_PPC_UDBG_16550) += legacy_serial.o udbg_16550.o
obj-$(CONFIG_STACKTRACE) += stacktrace.o
obj-$(CONFIG_SWIOTLB) += dma-swiotlb.o
pci64-$(CONFIG_PPC64) += pci_dn.o isa-bridge.o
obj-$(CONFIG_PCI) += pci_$(CONFIG_WORD_SIZE).o $(pci64-y) \
pci-common.o pci_of_scan.o
obj-$(CONFIG_PCI_MSI) += msi.o
obj-$(CONFIG_KEXEC) += machine_kexec.o crash.o \
machine_kexec_$(CONFIG_WORD_SIZE).o
obj-$(CONFIG_AUDIT) += audit.o
obj64-$(CONFIG_AUDIT) += compat_audit.o
obj-$(CONFIG_PPC_IO_WORKAROUNDS) += io-workarounds.o
obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o
obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o
obj-$(CONFIG_FTRACE_SYSCALLS) += ftrace.o
obj-$(CONFIG_8XX_MINIMAL_FPEMU) += softemu8xx.o
ifneq ($(CONFIG_PPC_INDIRECT_IO),y)
obj-y += iomap.o
endif
obj-$(CONFIG_PPC64) += $(obj64-y)
obj-$(CONFIG_PPC32) += $(obj32-y)
ifneq ($(CONFIG_XMON)$(CONFIG_KEXEC),)
obj-y += ppc_save_regs.o
endif
obj-$(CONFIG_EPAPR_PARAVIRT) += epapr_paravirt.o epapr_hcalls.o
obj-$(CONFIG_KVM_GUEST) += kvm.o kvm_emul.o
# Disable GCOV in odd or sensitive code
GCOV_PROFILE_prom_init.o := n
GCOV_PROFILE_ftrace.o := n
GCOV_PROFILE_machine_kexec_64.o := n
GCOV_PROFILE_machine_kexec_32.o := n
GCOV_PROFILE_kprobes.o := n
extra-$(CONFIG_PPC_FPU) += fpu.o
extra-$(CONFIG_ALTIVEC) += vector.o
extra-$(CONFIG_PPC64) += entry_64.o
extra-$(CONFIG_PPC_OF_BOOT_TRAMPOLINE) += prom_init.o
extra-y += systbl_chk.i
$(obj)/systbl.o: systbl_chk
quiet_cmd_systbl_chk = CALL $<
cmd_systbl_chk = $(CONFIG_SHELL) $< $(obj)/systbl_chk.i
PHONY += systbl_chk
systbl_chk: $(src)/systbl_chk.sh $(obj)/systbl_chk.i
$(call cmd,systbl_chk)
ifeq ($(CONFIG_PPC_OF_BOOT_TRAMPOLINE),y)
$(obj)/built-in.o: prom_init_check
quiet_cmd_prom_init_check = CALL $<
cmd_prom_init_check = $(CONFIG_SHELL) $< "$(NM)" "$(obj)/prom_init.o"
PHONY += prom_init_check
prom_init_check: $(src)/prom_init_check.sh $(obj)/prom_init.o
$(call cmd,prom_init_check)
endif
clean-files := vmlinux.lds