1 files changed, 20 insertions, 3 deletions

diff --git a/tools/scripts/Makefile.include b/tools/scripts/Makefile.include
index 96ce80a3743b..2964b96aa55f 100644
--- a/tools/scripts/Makefile.include
+++ b/tools/scripts/Makefile.include
@@ -1,8 +1,11 @@
-ifeq ("$(origin O)", "command line")
+ifeq ($(origin O), command line)
         dummy := $(if $(shell test -d $(O) || echo $(O)),$(error O=$(O) does not exist),)
         ABSOLUTE_O := $(shell cd $(O) ; pwd)
-        OUTPUT := $(ABSOLUTE_O)/
+        OUTPUT := $(ABSOLUTE_O)/$(if $(subdir),$(subdir)/)
         COMMAND_O := O=$(ABSOLUTE_O)
+ifeq ($(objtree),)
+        objtree := $(O)
+endif
 endif
 
 ifneq ($(OUTPUT),)
@@ -41,7 +44,16 @@ else
 NO_SUBDIR = :
 endif
 
-QUIET_SUBDIR0  = +$(MAKE) -C # space to separate -C and subdir
+#
+# Define a callable command for descending to a new directory
+#
+# Call by doing: $(call descend,directory[,target])
+#
+descend = \
+        +mkdir -p $(OUTPUT)$(1) && \
+        $(MAKE) $(COMMAND_O) subdir=$(if $(subdir),$(subdir)/$(1),$(1)) $(PRINT_DIR) -C $(1) $(2)
+
+QUIET_SUBDIR0  = +$(MAKE) $(COMMAND_O) -C # space to separate -C and subdir
 QUIET_SUBDIR1  =
 
 ifneq ($(findstring $(MAKEFLAGS),s),s)
@@ -56,5 +68,10 @@ ifndef V
                          $(MAKE) $(PRINT_DIR) -C $$subdir
         QUIET_FLEX     = @echo '   ' FLEX $@;
         QUIET_BISON    = @echo '   ' BISON $@;
+
+        descend = \
+                @echo '   ' DESCEND $(1); \
+                mkdir -p $(OUTPUT)$(1) && \
+                $(MAKE) $(COMMAND_O) subdir=$(if $(subdir),$(subdir)/$(1),$(1)) $(PRINT_DIR) -C $(1) $(2)
 endif
 endif