[PATCH 1/2] kbuild: asm-generic support

[Sam Ravnborg <sam@ravnborg.org>]

From 47a8c36e0549191ef8b0ba7dea01d7099b772760 Mon Sep 17 00:00:00 2001
From: Sam Ravnborg <sam@ravnborg.org>
Date: Sat, 8 Jan 2011 14:00:50 +0100
Subject: [PATCH 1/2] kbuild: asm-generic support

There is an increasing amount of header files
shared between individual architectures in asm-generic.
To avoid a lot of dummy wrapper files that just
include the corresponding file in asm-generic provide
some basic support in kbuild for this.

With the followign patch an architecture can maintain
a list of files in the file arch/$(ARCH)/include/asm-generic

For each file listed kbuild will generate the necessary wrapper
in arch/$(ARCH)/include/generated/asm.
When installing userspace headers a wrapper is likewise created.

The original inspiration for this came from the unicor32
patchset - although is used a different method.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Guan Xuetao <guanxuetao@mprc.pku.edu.cn>
Cc: Arnd Bergmann <arnd@arndb.de>
---
 Makefile                       |   12 +++++--
 include/asm-generic/Kbuild.asm |   66 ++++++++++++++++++++--------------------
 scripts/Makefile.headersinst   |   19 ++++++++++-
 scripts/asm-generic.sh         |   23 ++++++++++++++
 4 files changed, 82 insertions(+), 38 deletions(-)
 create mode 100644 scripts/asm-generic.sh

diff --git a/Makefile b/Makefile
index 74b2555..ee5437c 100644
--- a/Makefile
+++ b/Makefile
@@ -344,7 +344,8 @@ CFLAGS_GCOV	= -fprofile-arcs -ftest-coverage
 
 # Use LINUXINCLUDE when you must reference the include/ directory.
 # Needed to be compatible with the O= option
-LINUXINCLUDE    := -I$(srctree)/arch/$(hdr-arch)/include -Iinclude \
+LINUXINCLUDE    := -I$(srctree)/arch/$(hdr-arch)/include \
+                   -Iarch/$(hrd-arch)/include/generated -Iinclude \
                    $(if $(KBUILD_SRC), -I$(srctree)/include) \
                    -include include/generated/autoconf.h
 
@@ -411,6 +412,11 @@ ifneq ($(KBUILD_SRC),)
 	    $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
 endif
 
+# Support for using generic headers in asm-generic
+PHONY += asm-generic
+asm-generic:
+	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/asm-generic.sh $(SRCARCH)
+
 # To make sure we do not include .config for any of the *config targets
 # catch them early, and hand them over to scripts/kconfig/Makefile
 # It is allowed to specify more targets when calling make, including
@@ -942,7 +948,7 @@ ifneq ($(KBUILD_SRC),)
 endif
 
 # prepare2 creates a makefile if using a separate output directory
-prepare2: prepare3 outputmakefile
+prepare2: prepare3 outputmakefile asm-generic
 
 prepare1: prepare2 include/linux/version.h include/generated/utsrelease.h \
                    include/config/auto.conf
@@ -1016,7 +1022,7 @@ hdr-inst := -rR -f $(srctree)/scripts/Makefile.headersinst obj
 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/asm-$(hdr-arch), dst=include/asm)
 
 PHONY += __headers
-__headers: include/linux/version.h scripts_basic FORCE
+__headers: include/linux/version.h scripts_basic asm-generic FORCE
 	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
 
 PHONY += headers_install_all
diff --git a/include/asm-generic/Kbuild.asm b/include/asm-generic/Kbuild.asm
index c5d2e5d..f859a88 100644
--- a/include/asm-generic/Kbuild.asm
+++ b/include/asm-generic/Kbuild.asm
@@ -1,45 +1,45 @@
 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/kvm.h \
 		  $(srctree)/include/asm-$(SRCARCH)/kvm.h),)
-header-y  += kvm.h
+generic-y  += kvm.h
 endif
 
 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/kvm_para.h \
 		  $(srctree)/include/asm-$(SRCARCH)/kvm_para.h),)
-header-y  += kvm_para.h
+generic-y  += kvm_para.h
 endif
 
 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/a.out.h \
 		  $(srctree)/include/asm-$(SRCARCH)/a.out.h),)
-header-y += a.out.h
+generic-y += a.out.h
 endif
 
-header-y += auxvec.h
-header-y += bitsperlong.h
-header-y += byteorder.h
-header-y += errno.h
-header-y += fcntl.h
-header-y += ioctl.h
-header-y += ioctls.h
-header-y += ipcbuf.h
-header-y += mman.h
-header-y += msgbuf.h
-header-y += param.h
-header-y += poll.h
-header-y += posix_types.h
-header-y += ptrace.h
-header-y += resource.h
-header-y += sembuf.h
-header-y += setup.h
-header-y += shmbuf.h
-header-y += sigcontext.h
-header-y += siginfo.h
-header-y += signal.h
-header-y += socket.h
-header-y += sockios.h
-header-y += stat.h
-header-y += statfs.h
-header-y += swab.h
-header-y += termbits.h
-header-y += termios.h
-header-y += types.h
-header-y += unistd.h
+generic-y += auxvec.h
+generic-y += bitsperlong.h
+generic-y += byteorder.h
+generic-y += errno.h
+generic-y += fcntl.h
+generic-y += ioctl.h
+generic-y += ioctls.h
+generic-y += ipcbuf.h
+generic-y += mman.h
+generic-y += msgbuf.h
+generic-y += param.h
+generic-y += poll.h
+generic-y += posix_types.h
+generic-y += ptrace.h
+generic-y += resource.h
+generic-y += sembuf.h
+generic-y += setup.h
+generic-y += shmbuf.h
+generic-y += sigcontext.h
+generic-y += siginfo.h
+generic-y += signal.h
+generic-y += socket.h
+generic-y += sockios.h
+generic-y += stat.h
+generic-y += statfs.h
+generic-y += swab.h
+generic-y += termbits.h
+generic-y += termios.h
+generic-y += types.h
+generic-y += unistd.h
diff --git a/scripts/Makefile.headersinst b/scripts/Makefile.headersinst
index f89cb87..8cd8bb7 100644
--- a/scripts/Makefile.headersinst
+++ b/scripts/Makefile.headersinst
@@ -28,9 +28,10 @@ install-file  := $(install)/.install
 check-file    := $(install)/.check
 
 # all headers files for this dir
-all-files     := $(header-y) $(objhdr-y)
+all-files     := $(header-y) $(objhdr-y) $(generic-y)
 input-files   := $(addprefix $(srctree)/$(obj)/,$(header-y)) \
                  $(addprefix $(objtree)/$(obj)/,$(objhdr-y))
+generic-files := $(addprefix $(install)/,$(generic-y))
 output-files  := $(addprefix $(install)/, $(all-files))
 
 # Work out what needs to be removed
@@ -68,8 +69,22 @@ ifndef HDRCHECK
 __headersinst: $(subdirs) $(install-file)
 	@:
 
+# List of generic files may have two sources.
+# If a file exits in $(srctree)/$(obj) use it
+# otherwise create a dummy that arch/$(ARCH)/include/
+$(generic-files): scripts/headers_install.pl
+	$(Q)set -e;                                                       \
+	if [ -f $@ ]; then                                                \
+		$(PERL) $< $(dir $@) $(install) $(SRCARCH) $(notdir $@);  \
+	else                                                              \
+	        mkdir -p $(install);                                      \
+		echo "#include <asm-generic/$(notdir $@)>"                \
+	             > $(install)/$(notdir $@);                           \
+	fi
+
 targets += $(install-file)
-$(install-file): scripts/headers_install.pl $(input-files) FORCE
+$(install-file): scripts/headers_install.pl \
+                 $(input-files) $(generic-files) FORCE
 	$(if $(unwanted),$(call cmd,remove),)
 	$(if $(wildcard $(dir $@)),,$(shell mkdir -p $(dir $@)))
 	$(call if_changed,install)
diff --git a/scripts/asm-generic.sh b/scripts/asm-generic.sh
new file mode 100644
index 0000000..ec53b37
--- /dev/null
+++ b/scripts/asm-generic.sh
@@ -0,0 +1,23 @@
+#!/bin/sh
+#
+# include/asm-generic contains a lot of files that are used
+# verbatim by several architectures.
+# This scripts read the file arch/$(ARCH)/include/asm-generic
+# and for each file listed in this file create a small include
+# file in arch/$(ARCH)/include/generated/
+
+# If this arch does not have an asm-generic file exit
+if [ ! -e ${srctree}/arch/$1/include/asm-generic ]; then
+	exit 0
+fi
+
+# read list of header files form asm-generic
+files=$(grep -v ^# ${srctree}/arch/$1/include/asm-generic)
+
+gendir=arch/$1/include/generated/asm
+mkdir -p ${gendir}
+
+# create include files for each file used form asm-generic
+for F in ${files}; do
+	echo "#include <asm-generic/$F>" > ${gendir}/$F
+done
-- 
1.6.0.6