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linux/arch/powerpc/boot/Makefile
David Gibson cd197ffcf1 [POWERPC] zImage: Cleanup and improve zImage entry point
This patch re-organises the way the zImage wrapper code is entered, to
allow more flexibility on platforms with unusual entry conditions.
After this patch, a platform .o file has two options:

1) It can define a _zimage_start, in which case the platform code gets
   control from the very beginning of execution.  In this case the
   platform code is responsible for relocating the zImage if necessary,
   clearing the BSS, performing any platform specific initialization, and
   finally calling start() to load and enter the kernel.

2) It can define platform_init().  In this case the generic crt0.S
   handles initial entry, and calls platform_init() before calling
   start().  The signature of platform_init() is changed, however, to
   take up to 5 parameters (in r3..r7) as they come from the platform's
   initial loader, instead of a fixed set of parameters based on OF's
   usage.

   When using the generic crt0.S, the platform .o can optionally
   supply a custom stack to use, using the BSS_STACK() macro.  If this
   is not supplied, the crt0.S will assume that the loader has
   supplied a usable stack.

In either case, the platform code communicates information to the
generic code (specifically, a PROM pointer for OF systems, and/or an
initrd image address supplied by the bootloader) via a global
structure "loader_info".

In addition the wrapper script is rearranged to ensure that the
platform .o is always linked first.  This means that platforms where
the zImage entry point is at a fixed address or offset, rather than
being encoded in the binary header can be supported using option (1).

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-03-13 13:35:03 +11:00

191 lines
6.1 KiB
Makefile

# Makefile for making ELF bootable images for booting on CHRP
# using Open Firmware.
#
# Geert Uytterhoeven September 1997
#
# Based on coffboot by Paul Mackerras
# Simplified for ppc64 by Todd Inglett
#
# NOTE: this code is built for 32 bit in ELF32 format even though
# it packages a 64 bit kernel. We do this to simplify the
# bootloader and increase compatibility with OpenFirmware.
#
# To this end we need to define BOOTCC, etc, as the tools
# needed to build the 32 bit image. These are normally HOSTCC,
# but may be a third compiler if, for example, you are cross
# compiling from an intel box. Once the 64bit ppc gcc is
# stable it will probably simply be a compiler switch to
# compile for 32bit mode.
# To make it easier to setup a cross compiler,
# CROSS32_COMPILE is setup as a prefix just like CROSS_COMPILE
# in the toplevel makefile.
all: $(obj)/zImage
HOSTCC := gcc
BOOTCFLAGS := $(HOSTCFLAGS) -fno-builtin -nostdinc -isystem \
$(shell $(CROSS32CC) -print-file-name=include) -fPIC
BOOTAFLAGS := -D__ASSEMBLY__ $(BOOTCFLAGS) -traditional -nostdinc
ifeq ($(call cc-option-yn, -fstack-protector),y)
BOOTCFLAGS += -fno-stack-protector
endif
BOOTCFLAGS += -I$(obj) -I$(srctree)/$(obj)
zlib := inffast.c inflate.c inftrees.c
zlibheader := inffast.h inffixed.h inflate.h inftrees.h infutil.h
zliblinuxheader := zlib.h zconf.h zutil.h
$(addprefix $(obj)/,$(zlib) main.o): $(addprefix $(obj)/,$(zliblinuxheader)) \
$(addprefix $(obj)/,$(zlibheader))
src-wlib := string.S crt0.S stdio.c main.c flatdevtree.c flatdevtree_misc.c \
ns16550.c serial.c simple_alloc.c div64.S util.S \
gunzip_util.c $(zlib)
src-plat := of.c
src-boot := $(src-wlib) $(src-plat) empty.c
src-boot := $(addprefix $(obj)/, $(src-boot))
obj-boot := $(addsuffix .o, $(basename $(src-boot)))
obj-wlib := $(addsuffix .o, $(basename $(addprefix $(obj)/, $(src-wlib))))
obj-plat := $(addsuffix .o, $(basename $(addprefix $(obj)/, $(src-plat))))
quiet_cmd_copy_zlib = COPY $@
cmd_copy_zlib = sed "s@__attribute_used__@@;s@<linux/\([^>]\+\).*@\"\1\"@" $< > $@
quiet_cmd_copy_zlibheader = COPY $@
cmd_copy_zlibheader = sed "s@<linux/\([^>]\+\).*@\"\1\"@" $< > $@
# stddef.h for NULL
quiet_cmd_copy_zliblinuxheader = COPY $@
cmd_copy_zliblinuxheader = sed "s@<linux/string.h>@\"string.h\"@;s@<linux/kernel.h>@<stddef.h>@;s@<linux/\([^>]\+\).*@\"\1\"@" $< > $@
$(addprefix $(obj)/,$(zlib)): $(obj)/%: $(srctree)/lib/zlib_inflate/%
$(call cmd,copy_zlib)
$(addprefix $(obj)/,$(zlibheader)): $(obj)/%: $(srctree)/lib/zlib_inflate/%
$(call cmd,copy_zlibheader)
$(addprefix $(obj)/,$(zliblinuxheader)): $(obj)/%: $(srctree)/include/linux/%
$(call cmd,copy_zliblinuxheader)
$(obj)/empty.c:
@touch $@
$(obj)/zImage.lds $(obj)/zImage.coff.lds: $(obj)/%: $(srctree)/$(src)/%.S
@cp $< $@
clean-files := $(zlib) $(zlibheader) $(zliblinuxheader) \
empty.c zImage zImage.coff.lds zImage.lds zImage.sandpoint
quiet_cmd_bootcc = BOOTCC $@
cmd_bootcc = $(CROSS32CC) -Wp,-MD,$(depfile) $(BOOTCFLAGS) -c -o $@ $<
quiet_cmd_bootas = BOOTAS $@
cmd_bootas = $(CROSS32CC) -Wp,-MD,$(depfile) $(BOOTAFLAGS) -c -o $@ $<
quiet_cmd_bootar = BOOTAR $@
cmd_bootar = $(CROSS32AR) -cr $@.$$$$ $^; mv $@.$$$$ $@
$(patsubst %.c,%.o, $(filter %.c, $(src-boot))): %.o: %.c
$(call if_changed_dep,bootcc)
$(patsubst %.S,%.o, $(filter %.S, $(src-boot))): %.o: %.S
$(call if_changed_dep,bootas)
$(obj)/wrapper.a: $(obj-wlib)
$(call cmd,bootar)
hostprogs-y := addnote addRamDisk hack-coff mktree
extra-y := $(obj)/wrapper.a $(obj-plat) $(obj)/empty.o \
$(obj)/zImage.lds $(obj)/zImage.coff.lds
wrapper :=$(srctree)/$(src)/wrapper
wrapperbits := $(extra-y) $(addprefix $(obj)/,addnote hack-coff mktree)
#############
# Bits for building various flavours of zImage
ifneq ($(CROSS32_COMPILE),)
CROSSWRAP := -C "$(CROSS32_COMPILE)"
else
ifneq ($(CROSS_COMPILE),)
CROSSWRAP := -C "$(CROSS_COMPILE)"
endif
endif
quiet_cmd_wrap = WRAP $@
cmd_wrap =$(CONFIG_SHELL) $(wrapper) -c -o $@ -p $2 $(CROSSWRAP) vmlinux
quiet_cmd_wrap_initrd = WRAP $@
cmd_wrap_initrd =$(CONFIG_SHELL) $(wrapper) -c -o $@ -p $2 $(CROSSWRAP) \
-i $(obj)/ramdisk.image.gz vmlinux
$(obj)/zImage.chrp: vmlinux $(wrapperbits)
$(call cmd,wrap,chrp)
$(obj)/zImage.initrd.chrp: vmlinux $(wrapperbits)
$(call cmd,wrap_initrd,chrp)
$(obj)/zImage.pseries: vmlinux $(wrapperbits)
$(call cmd,wrap,pseries)
$(obj)/zImage.initrd.pseries: vmlinux $(wrapperbits)
$(call cmd,wrap_initrd,pseries)
$(obj)/zImage.pmac: vmlinux $(wrapperbits)
$(call cmd,wrap,pmac)
$(obj)/zImage.initrd.pmac: vmlinux $(wrapperbits)
$(call cmd,wrap_initrd,pmac)
$(obj)/zImage.coff: vmlinux $(wrapperbits)
$(call cmd,wrap,pmaccoff)
$(obj)/zImage.initrd.coff: vmlinux $(wrapperbits)
$(call cmd,wrap_initrd,pmaccoff)
$(obj)/zImage.miboot: vmlinux $(wrapperbits)
$(call cmd,wrap,miboot)
$(obj)/zImage.initrd.miboot: vmlinux $(wrapperbits)
$(call cmd,wrap_initrd,miboot)
$(obj)/zImage.ps3: vmlinux
$(STRIP) -s -R .comment $< -o $@
$(obj)/zImage.initrd.ps3: vmlinux
@echo " WARNING zImage.initrd.ps3 not supported (yet)"
$(obj)/uImage: vmlinux $(wrapperbits)
$(call cmd,wrap,uboot)
image-$(CONFIG_PPC_PSERIES) += zImage.pseries
image-$(CONFIG_PPC_MAPLE) += zImage.pseries
image-$(CONFIG_PPC_IBM_CELL_BLADE) += zImage.pseries
image-$(CONFIG_PPC_PS3) += zImage.ps3
image-$(CONFIG_PPC_CELLEB) += zImage.pseries
image-$(CONFIG_PPC_CHRP) += zImage.chrp
image-$(CONFIG_PPC_EFIKA) += zImage.chrp
image-$(CONFIG_PPC_PMAC) += zImage.pmac
image-$(CONFIG_DEFAULT_UIMAGE) += uImage
# For 32-bit powermacs, build the COFF and miboot images
# as well as the ELF images.
ifeq ($(CONFIG_PPC32),y)
image-$(CONFIG_PPC_PMAC) += zImage.coff zImage.miboot
endif
initrd-y := $(patsubst zImage%, zImage.initrd%, $(image-y))
$(obj)/zImage: $(addprefix $(obj)/, $(image-y))
@rm -f $@; ln $< $@
$(obj)/zImage.initrd: $(addprefix $(obj)/, $(initrd-y))
@rm -f $@; ln $< $@
install: $(CONFIGURE) $(image-y)
sh -x $(srctree)/$(src)/install.sh "$(KERNELRELEASE)" vmlinux System.map "$(INSTALL_PATH)" $<
clean-files += $(addprefix $(objtree)/, $(obj-boot) vmlinux.strip.gz)
clean-files += $(addprefix $(objtree)/, $(obj-boot) vmlinux.bin.gz)
clean-files += $(image-)