Re: [PATCH v4 10/19] Introduce asm-generic/*.h files

[Christoffer Dall <christoffer.dall@linaro.org>]

On Thu, Apr 10, 2014 at 06:56:51PM +0200, Andrew Jones wrote:
> Architecture neutral code may need to call low-level io accessors,
> or use spinlocks. Create a generic io.h to ensure those accessors
> are defined, and a generic spinlock.h that complains when included,
> as we can't write a generic spinlock. These files can be overridden
> or extended by architecture specific versions placed in
> lib/$ARCH/asm/.
> 
> Signed-off-by: Andrew Jones <drjones@redhat.com>
> ---
> v4: introduce lib/asm symlink to get rid of #ifdef __arm__,
>     add spinlock.h too
> v3: wrt to io.h (was libio.[ch]) only
>     - get rid of CONFIG_64BIT, replace with asserts
>     - get rid of {read,write}_len() [libio.c]
>     - fix bad *64_to_cpu macros
> ---
>  .gitignore                 |   1 +
>  Makefile                   |   6 +-
>  configure                  |  11 ++++
>  lib/asm-generic/io.h       | 154 +++++++++++++++++++++++++++++++++++++++++++++
>  lib/asm-generic/spinlock.h |   4 ++
>  5 files changed, 173 insertions(+), 3 deletions(-)
>  create mode 100644 lib/asm-generic/io.h
>  create mode 100644 lib/asm-generic/spinlock.h
> 
> diff --git a/.gitignore b/.gitignore
> index 775d0dfd8263e..e21939a8771e9 100644
> --- a/.gitignore
> +++ b/.gitignore
> @@ -9,6 +9,7 @@ patches
>  .stgit-*
>  cscope.*
>  *.swp
> +/lib/asm
>  /config.mak
>  /*-run
>  /test.log
> diff --git a/Makefile b/Makefile
> index fba58e36f272f..51cacdac00615 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -76,11 +76,11 @@ libfdt_clean:
>  	$(LIBFDT_objdir)/.*.d
>  
>  distclean: clean libfdt_clean
> -	$(RM) config.mak $(TEST_DIR)-run test.log msr.out cscope.*
> +	$(RM) lib/asm config.mak $(TEST_DIR)-run test.log msr.out cscope.*
>  
> -cscope: common_dirs = lib lib/libfdt
> +cscope: common_dirs = lib lib/libfdt lib/asm lib/asm-generic
>  cscope:
>  	$(RM) ./cscope.*
> -	find $(TEST_DIR) lib/$(TEST_DIR) $(common_dirs) -maxdepth 1 \
> +	find -L $(TEST_DIR) lib/$(TEST_DIR) $(common_dirs) -maxdepth 1 \
>  		-name '*.[chsS]' -print | sed 's,^\./,,' > ./cscope.files
>  	cscope -bk
> diff --git a/configure b/configure
> index 6cfc64943f6e6..8a81bf92e27b7 100755
> --- a/configure
> +++ b/configure
> @@ -95,6 +95,17 @@ if [ $exit -eq 0 ]; then
>  fi
>  rm -f lib_test.c
>  
> +# link lib/asm for the architecture
> +rm -f lib/asm
> +asm=asm-generic
> +if [ -d lib/$arch/asm ]; then
> +	asm=$arch/asm
> +elif [ -d lib/$testdir/asm ]; then
> +	asm=$testdir/asm

why do you need this elif?  can you not make sure arch is always set?

> +fi
> +ln -s $asm lib/asm
> +
> +# create the config
>  cat <<EOF > config.mak
>  PREFIX=$prefix
>  KERNELDIR=$(readlink -f $kerneldir)

[...]

-Christoffer