kbuild: rename prepare to archprepare to fix dependency chain

When introducing the generic asm-offsets.h support the dependency
chain for the prepare targets was changed. All build scripts expecting
include/asm/asm-offsets.h to be made when using the prepare target would broke.
With the limited number of prepare targets left in arch Makefiles
the trivial solution was to introduce a new arch specific target: archprepare

The dependency chain looks like this now:

prepare
  |
  +--> prepare0
         |
         +--> archprepare
                |
		+--> scripts_basic
                +--> prepare1
                       |
                       +---> prepare2
                               |
                               +--> prepare3

So prepare 3 is processed before prepare2 etc.
This guaantees that the asm symlink, version.h, scripts_basic
are all updated before archprepare is processed.

prepare0 which build the asm-offsets.h file will need the
actions performed by archprepare.

The head target is now named prepare, because users scripts will most
likely use that target, but prepare-all has been kept for compatibility.
Updated Documentation/kbuild/makefiles.txt.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

10 files changed, 30 insertions, 23 deletions

diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt
index 9a1586590d82..d802ce88bedc 100644
--- a/Documentation/kbuild/makefiles.txt
+++ b/Documentation/kbuild/makefiles.txt
@@ -31,7 +31,7 @@ This document describes the Linux kernel Makefiles.
 
         === 6 Architecture Makefiles
            --- 6.1 Set variables to tweak the build to the architecture
-           --- 6.2 Add prerequisites to prepare:
+           --- 6.2 Add prerequisites to archprepare:
            --- 6.3 List directories to visit when descending
            --- 6.4 Architecture specific boot images
            --- 6.5 Building non-kbuild targets
@@ -734,18 +734,18 @@ When kbuild executes the following steps are followed (roughly):
         for loadable kernel modules.
 
  
---- 6.2 Add prerequisites to prepare:
+--- 6.2 Add prerequisites to archprepare:
 
-        The prepare: rule is used to list prerequisites that needs to be
+        The archprepare: rule is used to list prerequisites that needs to be
         built before starting to descend down in the subdirectories.
         This is usual header files containing assembler constants.
 
                 Example:
-                #arch/s390/Makefile
-                prepare: include/asm-$(ARCH)/offsets.h
+                #arch/arm/Makefile
+                archprepare: maketools
 
-        In this example the file include/asm-$(ARCH)/offsets.h will
-        be built before descending down in the subdirectories.
+        In this example the file target maketools will be processed
+        before descending down in the subdirectories.
         See also chapter XXX-TODO that describe how kbuild supports
         generating offset header files.
 
diff --git a/Makefile b/Makefile
index 382298f37adf..e90ee6a3eef4 100644
--- a/Makefile
+++ b/Makefile
@@ -776,15 +776,20 @@ $(sort $(vmlinux-init) $(vmlinux-main)) $(vmlinux-lds): $(vmlinux-dirs) ;
 # Error messages still appears in the original language
 
 .PHONY: $(vmlinux-dirs)
-$(vmlinux-dirs): prepare-all scripts
+$(vmlinux-dirs): prepare scripts
         $(Q)$(MAKE) $(build)=$@
 
 # Things we need to do before we recursively start building the kernel
-# or the modules are listed in "prepare-all".
-# A multi level approach is used. prepare1 is updated first, then prepare0.
-# prepare-all is the collection point for the prepare targets.
+# or the modules are listed in "prepare".
+# A multi level approach is used. prepareN is processed before prepareN-1.
+# archprepare is used in arch Makefiles and when processed asm symlink,
+# version.h and scripts_basic is processed / created.
 
-.PHONY: prepare-all prepare prepare0 prepare1 prepare2 prepare3
+# Listed in dependency order
+.PHONY: prepare archprepare prepare0 prepare1 prepare2 prepare3
+
+# prepare-all is deprecated, use prepare as valid replacement
+.PHONY: prepare-all
 
 # prepare3 is used to check if we are building in a separate output directory,
 # and if so do:
@@ -813,11 +818,13 @@ ifneq ($(KBUILD_MODULES),)
         $(Q)mkdir -p $(MODVERDIR)
 endif
 
-prepare0: prepare prepare1 FORCE
+archprepare: prepare1 scripts_basic
+
+prepare0: archprepare FORCE
         $(Q)$(MAKE) $(build)=.
 
 # All the preparing..
-prepare-all: prepare0
+prepare prepare-all: prepare0
 
 #       Leave this as default for preprocessing vmlinux.lds.S, which is now
 #       done in arch/$(ARCH)/kernel/Makefile
@@ -908,7 +915,7 @@ modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux)
 
 # Target to prepare building external modules
 .PHONY: modules_prepare
-modules_prepare: prepare-all scripts
+modules_prepare: prepare scripts
 
 # Target to install modules
 .PHONY: modules_install
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index e625ac66f49b..130e6228b587 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -175,7 +175,7 @@ else
 endif
         @touch $@
 
-prepare: maketools include/asm-arm/.arch
+archprepare: maketools include/asm-arm/.arch
 
 .PHONY: maketools FORCE
 maketools: include/linux/version.h FORCE
diff --git a/arch/cris/Makefile b/arch/cris/Makefile
index a00043a91f16..ea65d585cf5e 100644
--- a/arch/cris/Makefile
+++ b/arch/cris/Makefile
@@ -107,7 +107,7 @@ archclean:
         rm -f timage vmlinux.bin decompress.bin rescue.bin cramfs.img
         rm -rf $(LD_SCRIPT).tmp
 
-prepare: $(SRC_ARCH)/.links $(srctree)/include/asm-$(ARCH)/.arch
+archprepare: $(SRC_ARCH)/.links $(srctree)/include/asm-$(ARCH)/.arch
 
 # Create some links to make all tools happy
 $(SRC_ARCH)/.links:
diff --git a/arch/ia64/Makefile b/arch/ia64/Makefile
index 7ed678cf5e41..70f8ed2748d1 100644
--- a/arch/ia64/Makefile
+++ b/arch/ia64/Makefile
@@ -82,7 +82,7 @@ unwcheck: vmlinux
 archclean:
         $(Q)$(MAKE) $(clean)=$(boot)
 
-prepare:  include/asm-ia64/.offsets.h.stamp
+archprepare:  include/asm-ia64/.offsets.h.stamp
 
 include/asm-ia64/.offsets.h.stamp:
         mkdir -p include/asm-ia64
diff --git a/arch/ppc/Makefile b/arch/ppc/Makefile
index 6dd7b50e0669..16e2675f3270 100644
--- a/arch/ppc/Makefile
+++ b/arch/ppc/Makefile
@@ -107,7 +107,7 @@ archclean:
         # Temporary hack until we have migrated to asm-powerpc
         $(Q)rm -rf arch/$(ARCH)/include
 
-prepare: checkbin
+archprepare: checkbin
 
 # Temporary hack until we have migrated to asm-powerpc
 include/asm: arch/$(ARCH)/include/asm
diff --git a/arch/sh/Makefile b/arch/sh/Makefile
index 19f00d57acf0..4a3049080b41 100644
--- a/arch/sh/Makefile
+++ b/arch/sh/Makefile
@@ -152,7 +152,7 @@ endif
         @touch $@
 
 
-prepare: maketools include/asm-sh/.cpu include/asm-sh/.mach
+archprepare: maketools include/asm-sh/.cpu include/asm-sh/.mach
 
 .PHONY: maketools FORCE
 maketools:  include/linux/version.h FORCE
diff --git a/arch/sh64/Makefile b/arch/sh64/Makefile
index 39073734a476..8ca57ffa2b70 100644
--- a/arch/sh64/Makefile
+++ b/arch/sh64/Makefile
@@ -73,7 +73,7 @@ compressed: zImage
 archclean:
         $(Q)$(MAKE) $(clean)=$(boot)
 
-prepare: arch/$(ARCH)/lib/syscalltab.h
+archprepare: arch/$(ARCH)/lib/syscalltab.h
 
 define filechk_gen-syscalltab
        (set -e; \
diff --git a/arch/um/Makefile b/arch/um/Makefile
index 154803a22698..ce987266dac6 100644
--- a/arch/um/Makefile
+++ b/arch/um/Makefile
@@ -107,7 +107,7 @@ else
 $(shell cd $(ARCH_DIR) && ln -sf Kconfig.$(SUBARCH) Kconfig.arch)
 endif
 
-prepare: $(ARCH_SYMLINKS) $(SYS_HEADERS) $(GEN_HEADERS)
+archprepare: $(ARCH_SYMLINKS) $(SYS_HEADERS) $(GEN_HEADERS)
 
 LINK-$(CONFIG_LD_SCRIPT_STATIC) += -static
 LINK-$(CONFIG_LD_SCRIPT_DYN) += -Wl,-rpath,/lib
diff --git a/arch/xtensa/Makefile b/arch/xtensa/Makefile
index 67ef4cd173b9..98fac8489aed 100644
--- a/arch/xtensa/Makefile
+++ b/arch/xtensa/Makefile
@@ -66,7 +66,7 @@ boot		:= arch/xtensa/boot
 
 archinc         := include/asm-xtensa
 
-prepare: $(archinc)/.platform
+archprepare: $(archinc)/.platform
 
 # Update machine cpu and platform symlinks if something which affects
 # them changed.