diff options
| -rw-r--r-- | .gitignore | 1 | ||||
| -rw-r--r-- | Documentation/kbuild/makefiles.txt | 36 | ||||
| -rw-r--r-- | Makefile | 16 | ||||
| -rw-r--r-- | scripts/Makefile.asm-generic | 23 | ||||
| -rw-r--r-- | scripts/Makefile.headersinst | 10 |
5 files changed, 81 insertions, 5 deletions
diff --git a/.gitignore b/.gitignore index 5d56a3fd0de6..9dacde0a4b2d 100644 --- a/.gitignore +++ b/.gitignore @@ -57,6 +57,7 @@ modules.builtin include/config include/linux/version.h include/generated +arch/*/include/generated # stgit generated dirs patches-* diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt index 40e082bb8c52..835b64acf0b4 100644 --- a/Documentation/kbuild/makefiles.txt +++ b/Documentation/kbuild/makefiles.txt @@ -40,11 +40,13 @@ This document describes the Linux kernel Makefiles. --- 6.6 Commands useful for building a boot image --- 6.7 Custom kbuild commands --- 6.8 Preprocessing linker scripts + --- 6.9 Generic header files === 7 Kbuild syntax for exported headers --- 7.1 header-y --- 7.2 objhdr-y --- 7.3 destination-y + --- 7.4 generic-y === 8 Kbuild Variables === 9 Makefile language @@ -1214,6 +1216,14 @@ When kbuild executes, the following steps are followed (roughly): The kbuild infrastructure for *lds file are used in several architecture-specific files. +--- 6.9 Generic header files + + The directory include/asm-generic contains the header files + that may be shared between individual architectures. + The recommended approach how to use a generic header file is + to list the file in the Kbuild file. + See "7.4 generic-y" for further info on syntax etc. + === 7 Kbuild syntax for exported headers The kernel include a set of headers that is exported to userspace. @@ -1270,6 +1280,32 @@ See subsequent chapter for the syntax of the Kbuild file. In the example above all exported headers in the Kbuild file will be located in the directory "include/linux" when exported. + --- 7.4 generic-y + + If an architecture uses a verbatim copy of a header from + include/asm-generic then this is listed in the file + arch/$(ARCH)/include/asm/Kbuild like this: + + Example: + #arch/x86/include/asm/Kbuild + generic-y += termios.h + generic-y += rtc.h + + During the prepare phase of the build a wrapper include + file is generated in the directory: + + arch/$(ARCH)/include/generated/asm + + When a header is exported where the architecture uses + the generic header a similar wrapper is generated as part + of the set of exported headers in the directory: + + usr/include/asm + + The generated wrapper will in both cases look like the following: + + Example: termios.h + #include <asm-generic/termios.h> === 8 Kbuild Variables @@ -349,7 +349,8 @@ 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/$(hdr-arch)/include/generated -Iinclude \ $(if $(KBUILD_SRC), -I$(srctree)/include) \ -include include/generated/autoconf.h @@ -417,6 +418,12 @@ ifneq ($(KBUILD_SRC),) $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL) endif +# Support for using generic headers in asm-generic +PHONY += asm-generic +asm-generic: + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \ + obj=arch/$(SRCARCH)/include/generated/asm + # 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 @@ -954,7 +961,7 @@ 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 @@ -1028,7 +1035,7 @@ 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) $(build)=scripts build_unifdef PHONY += headers_install_all @@ -1143,7 +1150,8 @@ CLEAN_FILES += vmlinux System.map \ .tmp_kallsyms* .tmp_version .tmp_vmlinux* .tmp_System.map # Directories & files removed with 'make mrproper' -MRPROPER_DIRS += include/config usr/include include/generated +MRPROPER_DIRS += include/config usr/include include/generated \ + arch/*/include/generated MRPROPER_FILES += .config .config.old .version .old_version \ include/linux/version.h \ Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS diff --git a/scripts/Makefile.asm-generic b/scripts/Makefile.asm-generic new file mode 100644 index 000000000000..a687cb697e35 --- /dev/null +++ b/scripts/Makefile.asm-generic @@ -0,0 +1,23 @@ +# include/asm-generic contains a lot of files that are used +# verbatim by several architectures. +# +# This Makefile reads the file arch/$(SRCARCH)/include/asm/Kbuild +# and for each file listed in this file with generic-y creates +# a small wrapper file in $(obj) (arch/$(SRCARCH)/include/generated/asm) + +kbuild-file := $(srctree)/arch/$(SRCARCH)/include/asm/Kbuild +include $(kbuild-file) + +include scripts/Kbuild.include + +# Create output directory if not already present +_dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj)) + +quiet_cmd_wrap = WRAP $@ +cmd_wrap = echo "\#include <asm-generic/$*.h>" >$@ + +all: $(patsubst %, $(obj)/%, $(generic-y)) + +$(obj)/%.h: + $(call cmd,wrap) + diff --git a/scripts/Makefile.headersinst b/scripts/Makefile.headersinst index f89cb87f5c01..a57f5bd5a13d 100644 --- a/scripts/Makefile.headersinst +++ b/scripts/Makefile.headersinst @@ -27,8 +27,13 @@ header-y := $(filter-out %/, $(header-y)) install-file := $(install)/.install check-file := $(install)/.check +# generic-y list all files an architecture uses from asm-generic +# Use this to build a list of headers which require a wrapper +wrapper-files := $(filter $(header-y), $(generic-y)) + # all headers files for this dir -all-files := $(header-y) $(objhdr-y) +header-y := $(filter-out $(generic-y), $(header-y)) +all-files := $(header-y) $(objhdr-y) $(wrapper-files) input-files := $(addprefix $(srctree)/$(obj)/,$(header-y)) \ $(addprefix $(objtree)/$(obj)/,$(objhdr-y)) output-files := $(addprefix $(install)/, $(all-files)) @@ -47,6 +52,9 @@ quiet_cmd_install = INSTALL $(printdir) ($(words $(all-files))\ cmd_install = \ $(PERL) $< $(srctree)/$(obj) $(install) $(SRCARCH) $(header-y); \ $(PERL) $< $(objtree)/$(obj) $(install) $(SRCARCH) $(objhdr-y); \ + for F in $(wrapper-files); do \ + echo "\#include <asm-generic/$$F>" > $(install)/$$F; \ + done; \ touch $@ quiet_cmd_remove = REMOVE $(unwanted) |