1 # Makefile for making ELF bootable images for booting on CHRP
4 # Geert Uytterhoeven September 1997
6 # Based on coffboot by Paul Mackerras
7 # Simplified for ppc64 by Todd Inglett
9 # NOTE: this code is built for 32 bit in ELF32 format even though
10 # it packages a 64 bit kernel. We do this to simplify the
11 # bootloader and increase compatibility with OpenFirmware.
13 # To this end we need to define BOOTCC, etc, as the tools
14 # needed to build the 32 bit image. These are normally HOSTCC,
15 # but may be a third compiler if, for example, you are cross
16 # compiling from an intel box. Once the 64bit ppc gcc is
17 # stable it will probably simply be a compiler switch to
18 # compile for 32bit mode.
19 # To make it easier to setup a cross compiler,
20 # CROSS32_COMPILE is setup as a prefix just like CROSS_COMPILE
21 # in the toplevel makefile.
24 #CROSS32_COMPILE = /usr/local/ppc/bin/powerpc-linux-
26 BOOTCC := $(CROSS32_COMPILE)gcc
28 BOOTCFLAGS := $(HOSTCFLAGS) $(LINUXINCLUDE) -fno-builtin
29 BOOTAS := $(CROSS32_COMPILE)as
30 BOOTAFLAGS := -D__ASSEMBLY__ $(BOOTCFLAGS) -traditional
31 BOOTLD := $(CROSS32_COMPILE)ld
32 BOOTLFLAGS := -Ttext 0x00400000 -e _start -T $(obj)/zImage.lds
33 BOOTOBJCOPY := $(CROSS32_COMPILE)objcopy
34 OBJCOPYFLAGS := contents,alloc,load,readonly,data
36 src-boot := crt0.S string.S prom.c main.c zlib.c imagesize.c div64.S
37 src-boot := $(addprefix $(obj)/, $(src-boot))
38 obj-boot := $(addsuffix .o, $(basename $(src-boot)))
40 quiet_cmd_bootcc = BOOTCC $@
41 cmd_bootcc = $(BOOTCC) -Wp,-MD,$(depfile) $(BOOTCFLAGS) -c -o $@ $<
43 quiet_cmd_bootas = BOOTAS $@
44 cmd_bootas = $(BOOTCC) -Wp,-MD,$(depfile) $(BOOTAFLAGS) -c -o $@ $<
46 $(patsubst %.c,%.o, $(filter %.c, $(src-boot))): %.o: %.c
47 $(call if_changed_dep,bootcc)
48 $(patsubst %.S,%.o, $(filter %.S, $(src-boot))): %.o: %.S
49 $(call if_changed_dep,bootas)
51 #-----------------------------------------------------------
52 # ELF sections within the zImage bootloader/wrapper
53 #-----------------------------------------------------------
54 required := vmlinux .config System.map
57 obj-sec = $(foreach section, $(1), $(patsubst %,$(obj)/kernel-%.o, $(section)))
58 src-sec = $(foreach section, $(1), $(patsubst %,$(obj)/kernel-%.c, $(section)))
59 gz-sec = $(foreach section, $(1), $(patsubst %,$(obj)/kernel-%.gz, $(section)))
61 hostprogs-y := piggy addnote addSystemMap addRamDisk
62 targets += zImage zImage.initrd imagesize.c \
63 $(patsubst $(obj)/%,%, $(call obj-sec, $(required) $(initrd))) \
64 $(patsubst $(obj)/%,%, $(call src-sec, $(required) $(initrd))) \
65 $(patsubst $(obj)/%,%, $(call gz-sec, $(required) $(initrd))) \
66 vmlinux.sm vmlinux.initrd vmlinux.sminitrd
67 extra-y := sysmap.o initrd.o
69 quiet_cmd_sysmap = SYSMAP $@
70 cmd_sysmap = $(obj)/addSystemMap System.map $< $@
71 $(obj)/vmlinux.sm: vmlinux $(obj)/addSystemMap System.map FORCE
72 $(call if_changed,sysmap)
74 quiet_cmd_ramdisk = RAMDISK $@
75 cmd_ramdisk = $(obj)/addRamDisk $(obj)/ramdisk.image.gz System.map $< $@
76 $(obj)/vmlinux.initrd: vmlinux $(obj)/addRamDisk $(obj)/ramdisk.image.gz System.map FORCE
77 $(call if_changed,ramdisk)
79 $(obj)/vmlinux.sminitrd: $(obj)/vmlinux.sm $(obj)/addRamDisk $(obj)/ramdisk.image.gz FORCE
80 $(call if_changed,ramdisk)
82 $(obj)/sysmap.o: System.map $(obj)/piggyback FORCE
83 $(call if_changed,piggy)
85 addsection = $(BOOTOBJCOPY) $(1) \
86 --add-section=.kernel:$(strip $(patsubst $(obj)/kernel-%.o,%, $(1)))=$(patsubst %.o,%.gz, $(1)) \
87 --set-section-flags=.kernel:$(strip $(patsubst $(obj)/kernel-%.o,%, $(1)))=$(OBJCOPYFLAGS)
89 quiet_cmd_addnote = ADDNOTE $@
90 cmd_addnote = $(BOOTLD) $(BOOTLFLAGS) -o $@ $(obj-boot) && $(obj)/addnote $@
92 quiet_cmd_piggy = PIGGY $@
93 cmd_piggy = $(obj)/piggyback $(@:.o=) < $< | $(BOOTAS) -o $@
95 $(call gz-sec, $(required)): $(obj)/kernel-%.gz: % FORCE
96 $(call if_changed,gzip)
98 $(obj)/kernel-initrd.gz: $(obj)/ramdisk.image.gz
99 cp -f $(obj)/ramdisk.image.gz $@
101 $(call src-sec, $(required) $(initrd)): $(obj)/kernel-%.c: $(obj)/kernel-%.gz FORCE
104 $(call obj-sec, $(required) $(initrd)): $(obj)/kernel-%.o: $(obj)/kernel-%.c FORCE
105 $(call if_changed_dep,bootcc)
106 $(call addsection, $@)
108 $(obj)/zImage: obj-boot += $(call obj-sec, $(required))
109 $(obj)/zImage: $(call obj-sec, $(required)) $(obj-boot) $(obj)/addnote FORCE
110 $(call if_changed,addnote)
112 $(obj)/zImage.initrd: obj-boot += $(call obj-sec, $(required) $(initrd))
113 $(obj)/zImage.initrd: $(call obj-sec, $(required) $(initrd)) $(obj-boot) $(obj)/addnote FORCE
114 $(call if_changed,addnote)
116 $(obj)/imagesize.c: vmlinux
119 awk '{printf "/* generated -- do not edit! */\n" \
120 "unsigned long vmlinux_filesize = %d;\n", $$5}' > $(obj)/imagesize.c
121 $(CROSS_COMPILE)nm -n vmlinux | tail -n 1 | \
122 awk '{printf "unsigned long vmlinux_memsize = 0x%s;\n", substr($$1,8)}' \
123 >> $(obj)/imagesize.c
125 install: $(CONFIGURE) $(obj)/$(BOOTIMAGE)
126 sh -x $(src)/install.sh "$(KERNELRELEASE)" "$(obj)/$(BOOTIMAGE)" "$(TOPDIR)/System.map" "$(INSTALL_PATH)"
128 clean-files := $(patsubst $(obj)/%,%, $(obj-boot))