Merge master.kernel.org:/pub/scm/linux/kernel/git/sam/kbuild

25 files changed, 397 insertions, 147 deletions

diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
new file mode 100644
index 000000000000..9087273abf91
--- /dev/null
+++ b/scripts/Kbuild.include
@@ -0,0 +1,96 @@
+####
+# kbuild: Generic definitions
+
+# Convinient variables
+comma   := ,
+empty   :=
+space   := $(empty) $(empty)
+
+###
+# The temporary file to save gcc -MD generated dependencies must not
+# contain a comma
+depfile = $(subst $(comma),_,$(@D)/.$(@F).d)
+
+###
+# filechk is used to check if the content of a generated file is updated.
+# Sample usage:
+# define filechk_sample
+#       echo $KERNELRELEASE
+# endef
+# version.h : Makefile
+#       $(call filechk,sample)
+# The rule defined shall write to stdout the content of the new file.
+# The existing file will be compared with the new one.
+# - If no file exist it is created
+# - If the content differ the new file is used
+# - If they are equal no change, and no timestamp update
+# - stdin is piped in from the first prerequisite ($<) so one has
+#   to specify a valid file as first prerequisite (often the kbuild file)
+define filechk
+        $(Q)set -e;                             \
+        echo '  CHK     $@';                    \
+        mkdir -p $(dir $@);                     \
+        $(filechk_$(1)) < $< > $@.tmp;          \
+        if [ -r $@ ] && cmp -s $@ $@.tmp; then  \
+                rm -f $@.tmp;                   \
+        else                                    \
+                echo '  UPD     $@';            \
+                mv -f $@.tmp $@;                \
+        fi
+endef
+
+###
+# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
+# Usage:
+# $(Q)$(MAKE) $(build)=dir
+build := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.build obj
+
+# If quiet is set, only print short version of command
+cmd = @$(if $($(quiet)cmd_$(1)),\
+      echo '  $(subst ','\'',$($(quiet)cmd_$(1)))' &&) $(cmd_$(1))
+
+###
+# if_changed      - execute command if any prerequisite is newer than 
+#                   target, or command line has changed
+# if_changed_dep  - as if_changed, but uses fixdep to reveal dependencies
+#                   including used config symbols
+# if_changed_rule - as if_changed but execute rule instead
+# See Documentation/kbuild/makefiles.txt for more info
+
+ifneq ($(KBUILD_NOCMDDEP),1)
+# Check if both arguments has same arguments. Result in empty string if equal
+# User may override this check using make KBUILD_NOCMDDEP=1
+arg-check = $(strip $(filter-out $(1), $(2)) $(filter-out $(2), $(1)) )
+endif
+
+# echo command. Short version is $(quiet) equals quiet, otherwise full command
+echo-cmd = $(if $($(quiet)cmd_$(1)), \
+        echo '  $(subst ','\'',$($(quiet)cmd_$(1)))';)
+
+# function to only execute the passed command if necessary
+# >'< substitution is for echo to work, >$< substitution to preserve $ when reloading .cmd file
+# note: when using inline perl scripts [perl -e '...$$t=1;...'] in $(cmd_xxx) double $$ your perl vars
+# 
+if_changed = $(if $(strip $? $(call arg-check, $(cmd_$(1)), $(cmd_$@)) ), \
+        @set -e; \
+        $(echo-cmd) \
+        $(cmd_$(1)); \
+        echo 'cmd_$@ := $(subst $$,$$$$,$(subst ','\'',$(cmd_$(1))))' > $(@D)/.$(@F).cmd)
+
+# execute the command and also postprocess generated .d dependencies
+# file
+if_changed_dep = $(if $(strip $? $(filter-out FORCE $(wildcard $^),$^)\
+        $(call arg-check, $(cmd_$(1)), $(cmd_$@)) ),                  \
+        @set -e; \
+        $(echo-cmd) \
+        $(cmd_$(1)); \
+        scripts/basic/fixdep $(depfile) $@ '$(subst $$,$$$$,$(subst ','\'',$(cmd_$(1))))' > $(@D)/.$(@F).tmp; \
+        rm -f $(depfile); \
+        mv -f $(@D)/.$(@F).tmp $(@D)/.$(@F).cmd)
+
+# Usage: $(call if_changed_rule,foo)
+# will check if $(cmd_foo) changed, or any of the prequisites changed,
+# and if so will execute $(rule_foo)
+if_changed_rule = $(if $(strip $? $(call arg-check, $(cmd_$(1)), $(cmd_$@)) ),\
+                        @set -e; \
+                        $(rule_$(1)))
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 76ba6be3dfc9..506e3f3befe3 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -10,8 +10,11 @@ __build:
 # Read .config if it exist, otherwise ignore
 -include .config
 
-include $(if $(wildcard $(obj)/Kbuild), $(obj)/Kbuild, $(obj)/Makefile)
+# The filename Kbuild has precedence over Makefile
+kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
+include $(if $(wildcard $(kbuild-dir)/Kbuild), $(kbuild-dir)/Kbuild, $(kbuild-dir)/Makefile)
 
+include scripts/Kbuild.include
 include scripts/Makefile.lib
 
 ifdef host-progs
@@ -169,7 +172,7 @@ cmd_modversions =							\
                         -T $(@D)/.tmp_$(@F:.o=.ver);                    \
                 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);        \
         else                                                            \
-                mv $(@D)/.tmp_$(@F) $@;                                 \
+                mv -f $(@D)/.tmp_$(@F) $@;                              \
         fi;
 endif
 
diff --git a/scripts/Makefile.clean b/scripts/Makefile.clean
index ff3e87dbf387..8974ea5fc878 100644
--- a/scripts/Makefile.clean
+++ b/scripts/Makefile.clean
@@ -7,7 +7,14 @@ src := $(obj)
 .PHONY: __clean
 __clean:
 
-include $(if $(wildcard $(obj)/Kbuild), $(obj)/Kbuild, $(obj)/Makefile)
+# Shorthand for $(Q)$(MAKE) scripts/Makefile.clean obj=dir
+# Usage:
+# $(Q)$(MAKE) $(clean)=dir
+clean := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.clean obj
+
+# The filename Kbuild has precedence over Makefile
+kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
+include $(if $(wildcard $(kbuild-dir)/Kbuild), $(kbuild-dir)/Kbuild, $(kbuild-dir)/Makefile)
 
 # Figure out what we need to build from the various variables
 # ==========================================================================
@@ -87,8 +94,3 @@ $(subdir-ymn):
 # If quiet is set, only print short version of command
 
 cmd = @$(if $($(quiet)cmd_$(1)),echo '  $($(quiet)cmd_$(1))' &&) $(cmd_$(1))
-
-# Shorthand for $(Q)$(MAKE) scripts/Makefile.clean obj=dir
-# Usage:
-# $(Q)$(MAKE) $(clean)=dir
-clean := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.clean obj
diff --git a/scripts/Makefile.host b/scripts/Makefile.host
index 2821a2b83bbb..2d519704b8fd 100644
--- a/scripts/Makefile.host
+++ b/