From 16a354f920f3959ed847bd917bdfbc7eba48cf1e Mon Sep 17 00:00:00 2001 From: Wolfgang Denk Date: Tue, 26 Oct 2010 00:08:35 +0200 Subject: [PATCH] include/asm-offsets.h: automatically generate assembler constants A recurrent issue is that certain C level constructs like sizeof() or offsetof() cannot be used in assembler files, which is inconvenient when such constructs are used in the definition of macro names etc. To avoid duplication of such definitions (and thus another cause of problems), we adapt the Linux way to automatically generate the respective definitions from the respective C header files. In Linux, this is implemented in include/linux/kbuild.h, Kbuild, and arch/*/kernel/asm-offsets.c; we adapt the code from the Linux v2.6.36 kernel tree. We also copy the concept of the include/generated/ directory which can be used to hold other automatically generated files as well. We start with an architecture-independent lib/asm-offsets.c which generates include/generated/generic-asm-offsets.h (included by include/asm-offsets.h, which is what will be referred to in the actual source code). Later this may be extended by architecture-specific arch/*/lib/asm-offsets.c files that will generate a include/generated/asm-offsets.h. Signed-off-by: Wolfgang Denk Acked-by: Kumar Gala --- .gitignore | 3 +++ Makefile | 21 +++++++++++++++++++-- include/asm-offsets.h | 2 ++ include/linux/kbuild.h | 20 ++++++++++++++++++++ lib/asm-offsets.c | 25 +++++++++++++++++++++++++ tools/scripts/make-asm-offsets | 27 +++++++++++++++++++++++++++ 6 files changed, 96 insertions(+), 2 deletions(-) create mode 100644 include/asm-offsets.h create mode 100644 include/linux/kbuild.h create mode 100644 lib/asm-offsets.c create mode 100755 tools/scripts/make-asm-offsets diff --git a/.gitignore b/.gitignore index 67d2cd62c0..e71f6ac474 100644 --- a/.gitignore +++ b/.gitignore @@ -40,6 +40,9 @@ /errlog /reloc_off +/include/generated/ +/lib/asm-offsets.s + # stgit generated dirs patches-* .stgit-edit.txt diff --git a/Makefile b/Makefile index f9f83eb12f..b50830a45f 100644 --- a/Makefile +++ b/Makefile @@ -372,7 +372,8 @@ GEN_UBOOT = \ cd $(LNDIR) && $(LD) $(LDFLAGS) $$UNDEF_SYM $(__OBJS) \ --start-group $(__LIBS) --end-group $(PLATFORM_LIBS) \ -Map u-boot.map -o u-boot -$(obj)u-boot: depend $(SUBDIRS) $(OBJS) $(LIBBOARD) $(LIBS) $(LDSCRIPT) $(obj)u-boot.lds +$(obj)u-boot: depend \ + $(SUBDIRS) $(OBJS) $(LIBBOARD) $(LIBS) $(LDSCRIPT) $(obj)u-boot.lds $(GEN_UBOOT) ifeq ($(CONFIG_KALLSYMS),y) smap=`$(call SYSTEM_MAP,u-boot) | \ @@ -426,7 +427,9 @@ updater: # Explicitly make _depend in subdirs containing multiple targets to prevent # parallel sub-makes creating .depend files simultaneously. -depend dep: $(TIMESTAMP_FILE) $(VERSION_FILE) $(obj)include/autoconf.mk +depend dep: $(TIMESTAMP_FILE) $(VERSION_FILE) \ + $(obj)include/autoconf.mk \ + $(obj)include/generated/generic-asm-offsets.h for dir in $(SUBDIRS) $(CPUDIR) $(dir $(LDSCRIPT)) ; do \ $(MAKE) -C $$dir _depend ; done @@ -473,6 +476,18 @@ $(obj)include/autoconf.mk: $(obj)include/config.h sed -n -f tools/scripts/define2mk.sed > $@.tmp && \ mv $@.tmp $@ +$(obj)include/generated/generic-asm-offsets.h: $(obj)include/autoconf.mk.dep \ + $(obj)lib/asm-offsets.s + @$(XECHO) Generating $@ + tools/scripts/make-asm-offsets $(obj)lib/asm-offsets.s $@ + +$(obj)lib/asm-offsets.s: $(obj)include/autoconf.mk.dep \ + $(src)lib/asm-offsets.c + @mkdir -p $(obj)lib + $(CC) -DDO_DEPS_ONLY \ + $(CFLAGS) $(CFLAGS_$(BCURDIR)/$(@F)) $(CFLAGS_$(BCURDIR)) \ + -o $@ $(src)lib/asm-offsets.c -c -S + ######################################################################### else # !config.mk all $(obj)u-boot.hex $(obj)u-boot.srec $(obj)u-boot.bin \ @@ -1206,6 +1221,7 @@ clean: $(obj)u-boot.lds \ $(obj)arch/blackfin/cpu/bootrom-asm-offsets.[chs] @rm -f $(obj)include/bmp_logo.h + @rm -f $(obj)lib/asm-offsets.s @rm -f $(obj)nand_spl/{u-boot.lds,u-boot-spl,u-boot-spl.map,System.map} @rm -f $(obj)onenand_ipl/onenand-{ipl,ipl.bin,ipl.map} @rm -f $(ONENAND_BIN) @@ -1229,6 +1245,7 @@ clobber: clean @rm -f $(obj)tools/{env/crc32.c,inca-swap-bytes} @rm -f $(obj)arch/powerpc/cpu/mpc824x/bedbug_603e.c @rm -f $(obj)include/asm/proc $(obj)include/asm/arch $(obj)include/asm + @rm -fr $(obj)include/generated @[ ! -d $(obj)nand_spl ] || find $(obj)nand_spl -name "*" -type l -print | xargs rm -f @[ ! -d $(obj)onenand_ipl ] || find $(obj)onenand_ipl -name "*" -type l -print | xargs rm -f diff --git a/include/asm-offsets.h b/include/asm-offsets.h new file mode 100644 index 0000000000..ab28184054 --- /dev/null +++ b/include/asm-offsets.h @@ -0,0 +1,2 @@ +#include +/* #include */ diff --git a/include/linux/kbuild.h b/include/linux/kbuild.h new file mode 100644 index 0000000000..be763842c0 --- /dev/null +++ b/include/linux/kbuild.h @@ -0,0 +1,20 @@ +/* + * Copied from Linux: + * commit 37487a56523d402e25650da16c337acf4cecd13d + * Author: Christoph Lameter + */ +#ifndef __LINUX_KBUILD_H +#define __LINUX_KBUILD_H + +#define DEFINE(sym, val) \ + asm volatile("\n->" #sym " %0 " #val : : "i" (val)) + +#define BLANK() asm volatile("\n->" : : ) + +#define OFFSET(sym, str, mem) \ + DEFINE(sym, offsetof(struct str, mem)) + +#define COMMENT(x) \ + asm volatile("\n->#" x) + +#endif diff --git a/lib/asm-offsets.c b/lib/asm-offsets.c new file mode 100644 index 0000000000..4eb61747c4 --- /dev/null +++ b/lib/asm-offsets.c @@ -0,0 +1,25 @@ +/* + * Adapted from Linux v2.6.36 kernel: arch/powerpc/kernel/asm-offsets.c + * + * This program is used to generate definitions needed by + * assembly language modules. + * + * We use the technique used in the OSF Mach kernel code: + * generate asm statements containing #defines, + * compile this file to assembler, and then extract the + * #defines from the assembly-language output. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include + +#include + +int main(void) +{ + return 0; +} diff --git a/tools/scripts/make-asm-offsets b/tools/scripts/make-asm-offsets new file mode 100755 index 0000000000..61c095f426 --- /dev/null +++ b/tools/scripts/make-asm-offsets @@ -0,0 +1,27 @@ +#!/bin/sh + +# Adapted from Linux kernel's "Kbuild": +# commit 1cdf25d704f7951d02a04064c97db547d6021872 +# Author: Christoph Lameter + +mkdir -p $(dirname $2) + +# Default sed regexp - multiline due to syntax constraints +SED_CMD="/^->/{s:->#\(.*\):/* \1 */:; \ + s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 (\2) /* \3 */:; \ + s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \ + s:->::; p;}" + +(set -e + echo "#ifndef __ASM_OFFSETS_H__" + echo "#define __ASM_OFFSETS_H__" + echo "/*" + echo " * DO NOT MODIFY." + echo " *" + echo " * This file was generated by $(basename $0)" + echo " *" + echo " */" + echo "" + sed -ne "${SED_CMD}" $1 + echo "" + echo "#endif" ) > $2 -- 2.39.2