When Kconfig for U-boot was examined, one of the biggest issues was
how to support multiple images (Normal, SPL, TPL). There were
actually two options, "single .config" and "multiple .config".
After some discussions and thought experiments, I chose the latter,
i.e. to create ".config", "spl/.config", "tpl/.config" for Normal,
SPL, TPL, respectively.
It is true that the "multiple .config" strategy provided us the
maximum flexibility and helped to avoid duplicating CONFIGs among
Normal, SPL, TPL, but I have noticed some fatal problems:
[1] It is impossible to share CONFIG options across the images.
If you change the configuration of Main image, you often have to
adjust some SPL configurations correspondingly. Currently, we
cannot handle the dependencies between them. It means one of the
biggest advantages of Kconfig is lost.
[2] It is too painful to change both ".config" and "spl/.config".
Sunxi guys started to work around this problem by creating a new
configuration target. Commit cbdd9a9737 (sunxi: kconfig: Add
%_felconfig rule to enable FEL build of sunxi platforms.) added
"make *_felconfig" to enable CONFIG_SPL_FEL on both images.
Changing the configuration of multiple images in one command is a
generic demand. The current implementation cannot propose any
good solution about this.
[3] Kconfig files are getting ugly and difficult to understand.
Commit b724bd7d63 (dm: Kconfig: Move CONFIG_SYS_MALLOC_F_LEN to
Kconfig) has sprinkled "if !SPL_BUILD" over the Kconfig files.
[4] The build system got more complicated than it should be.
To adjust Linux-originated Kconfig to U-Boot, the helper script
"scripts/multiconfig.sh" was introduced. Writing a complicated
text processor is a shell script sometimes caused problems.
Now I believe the "single .config" will serve us better. With it,
all the problems above would go away. Instead, we will have to add
some CONFIG_SPL_* (and CONFIG_TPL_*) options such as CONFIG_SPL_DM,
but we will not have much. Anyway, this is what we do now in
scripts/Makefile.spl.
I admit my mistake with my apology and this commit switches to the
single .config configuration.
It is not so difficult to do that:
- Remove unnecessary processings from scripts/multiconfig.sh
This file will remain for a while to support the current defconfig
format. It will be removed after more cleanups are done.
- Adjust some makefiles and Kconfigs
- Add some entries to include/config_uncmd_spl.h and the new file
scripts/Makefile.uncmd_spl. Some CONFIG options that are not
supported on SPL must be disabled because one .config is shared
between SPL and U-Boot proper going forward. I know this is not
a beautiful solution and I think we can do better, but let's see
how much we will have to describe them.
- update doc/README.kconfig
More cleaning up patches will follow this.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
This commit imports some updates in misc scripts from Linux 3.18-rc1.
[1] commit cbb4d3e6510b99522719c5ef0 by Horia Geanta
scripts/kernel-doc: handle object-like macros
[2] commit 164f0d2efaaef83 by Michal Marek
kbuild: Fix handling of backslashes in *.cmd files
[3] commit 270a00963cd367214e by Randy Dunlap
scripts/kernel-doc: recognize __meminit
[4] commit a4954fd7724c0f55361eb5 by Masahiro Yamada
kbuild: remove obj-n and lib-n handling
[5] commit 5b2389b45d1a9c12b9f by Masahiro Yamada
kbuild: simplify build, clean, modbuiltin shorthands
Signed-off-by: Horia Geanta <horia.geanta@freescale.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Since Linux 3.18-rc1, Kbuild is able to handle multi-objs
dependency correctly, which also allows us futher cleanups
of some makefiles.
This commit imports those commits:
[1] commit c8589d1e9e01 by Masahiro Yamada
kbuild: handle multi-objs dependency appropriately
[2] commit 97e3226e6e98 by Masahiro Yamada
kbuild: handle the dependency of multi-objs hostprogs appropriately
[3] commit 022af62d0190 by Masahiro Yamada
kbuild: refactor script/kconfig/Makefile
[4] commit 221ecca6cafe by Masahiro Yamada
kbuild: remove redundant clean-files from scripts/kconfig/Makefile
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
This commit was imported from Linux Kernel:
commit a86fe353 written by me.
W=... provides extra gcc checks.
Having such code in scripts/Makefile.build results in the same flags
being added to KBUILD_CFLAGS multiple times becuase
scripts/Makefile.build is invoked every time Kbuild descends into
the subdirectories.
Since the top Makefile is already too cluttered, this commit moves
all of extra gcc check stuff to a new file scripts/Makefile.extrawarn,
which is included from the top Makefile.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
This commit enables Kconfig.
Going forward, we use Kconfig for the board configuration.
mkconfig will never be used. Nor will include/config.mk be generated.
Kconfig must be adjusted for U-Boot because our situation is
a little more complicated than Linux Kernel.
We have to generate multiple boot images (Normal, SPL, TPL)
from one source tree.
Each image needs its own configuration input.
Usage:
Run "make <board>_defconfig" to do the board configuration.
It will create the .config file and additionally spl/.config, tpl/.config
if SPL, TPL is enabled, respectively.
You can use "make config", "make menuconfig" etc. to create
a new .config or modify the existing one.
Use "make spl/config", "make spl/menuconfig" etc. for spl/.config
and do likewise for tpl/.config file.
The generic syntax of configuration targets for SPL, TPL is:
<target_image>/<config_command>
Here, <target_image> is either 'spl' or 'tpl'
<config_command> is 'config', 'menuconfig', 'xconfig', etc.
When the configuration is done, run "make".
(Or "make <board>_defconfig all" will do the configuration and build
in one time.)
For futher information of how Kconfig works in U-Boot,
please read the comment block of scripts/multiconfig.py.
By the way, there is another item worth remarking here:
coexistence of Kconfig and board herder files.
Prior to Kconfig, we used C headers to define a set of configs.
We expect a very long term to migrate from C headers to Kconfig.
Two different infractructure must coexist in the interim.
In our former configuration scheme, include/autoconf.mk was generated
for use in makefiles.
It is still generated under include/, spl/include/, tpl/include/ directory
for the Normal, SPL, TPL image, respectively.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Simon Glass <sjg@chromium.org>
Kbuild brought about many advantages for us but a significant
performance regression was reported by Simon Glass.
After some discussions and analysis, it turned out
its main cause is in $(call cc-option,...).
Historically, U-Boot parses all config.mk
(arch/*/config.mk and board/*/config.mk)
every time descending into subdirectories.
That means cc-options are evaluated over and over again.
$(call cc-option,...) is useful but costly.
So we want to evaluate them only in ./Makefile
and spl/Makefile and export compiler flags.
This commit changes the build system as follows:
- Modify scripts/Makefile.build to not include config.mk
Instead, add $(PLATFORM_CPPFLAGS) to asflags-y, ccflags-y,
cppflags-y.
- Export many variables
Going forward, Kbuild will not parse config.mk files
when it descends into subdirectories.
If we want to set variables in config.mk and use them
in subdirectories, they must be exported.
This is the list of variables to get exported:
PLATFORM_CPPFLAGS
CPUDIR
BOARDDIR
OBJCOPYFLAGS
LDFLAGS
LDFLAGS_FINAL
(used in nand_spl/board/*/*/Makefile)
CONFIG_STANDALONE_LOAD_ADDR
(used in examples/standalone/Makefile)
SYM_PREFIX
(used in examples/standalone/Makefile)
RELFLAGS
(used in examples/standalone/Makefile)
- Delete CPPFLAGS
This variable has been replaced with PLATFORM_CPPFLAGS
- Copy gcclibdir from example/standalone/Makefile
to arch/sparc/config.mk
The reference in CONFIG_STANDALONE_LOAD_ADDR must be
resolved before it is exported.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Reported-by: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org> [on Sandbox]
Tested-by: Stephen Warren <swarren@nvidia.com> [on Tegra]
This commit changes the location of include directives
of board configuration files.
The purpose of this change is:
- Slim down $(TOPDIR)/config.mk
- Prevent $(TOPDIR)/Makefile from including the same
configuration file twice
- Do not include include/config.mk multiple times
because ARCH, CPU, BOARD, VENDOR, SOC are exported
Before this commit:
- include/autoconf.mk was included from $(TOPDIR)/Makefile
and $(TOPDIR)/config.mk
(This means $(TOPDIR)/Makefile included include/autoconf.mk twice)
- include/{spl,tpl}-autoconf.mk was included from $(TOPDIR)/config.mk
- include/config.mk was included from $(TOPDIR)/Makefile
and $(TOPDIR)/config.mk
(This means $(TOPDIR)/Makefile included include/config.mk twice)
After this commit:
- include/autoconf.mk is included from $(TOPDIR)/Makefile
and $(TOPDIR)/scripts/Makefile.build
- include/{spl,tpl}-autoconf.mk is included from $(TOPDIR)/spl/Makefile
and $(TOPDIR)/scripts/Makefile.build
- include/config.mk is included from $(TOPDIR)/config.mk and
$(TOPDIR)/spl/Makefile
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Now we are ready to switch over to real Kbuild.
This commit disables temporary scripts:
scripts/{Makefile.build.tmp, Makefile.host.tmp}
and enables real Kbuild scripts:
scripts/{Makefile.build,Makefile.host,Makefile.lib}.
This switch is triggered by the line in scripts/Kbuild.include
-build := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.build.tmp obj
+build := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.build obj
We need to adjust some build scripts for U-Boot.
But smaller amount of modification is preferable.
Additionally, we need to fix compiler flags which are
locally added or removed.
In Kbuild, it is not allowed to change CFLAGS locally.
Instead, ccflags-y, asflags-y, cppflags-y,
CFLAGS_$(basetarget).o, CFLAGS_REMOVE_$(basetarget).o
are prepared for that purpose.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Tested-by: Gerhard Sittig <gsi@denx.de>
This commit imports build scripts from Linux Kernel v3.13
as they are.
I know they include some trailing spaces
but I am intentionally keeping them untouched.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Some build scripts including scripts/Makefile.build
will be imported from Linux Kernel in the next commit.
We need to adjust them for U-Boot in the following commits.
To make it easier for reviewers to track the modification,
this commit renames scripts/Makefile.build to
scripts/Makefile.build.tmp beforehand.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
This commit changes the working directory
where the build process occurs.
Before this commit, build process occurred under the source
tree for both in-tree and out-of-tree build.
That's why we needed to add $(obj) prefix to all generated
files in makefiles like follows:
$(obj)u-boot.bin: $(obj)u-boot
Here, $(obj) is empty for in-tree build, whereas it points
to the output directory for out-of-tree build.
And our old build system changes the current working directory
with "make -C <sub-dir>" syntax when descending into the
sub-directories.
On the other hand, Kbuild uses a different idea
to handle out-of-tree build and directory descending.
The build process of Kbuild always occurs under the output tree.
When "O=dir/to/store/output/files" is given, the build system
changes the current working directory to that directory and
restarts the make.
Kbuild uses "make -f $(srctree)/scripts/Makefile.build obj=<sub-dir>"
syntax for descending into sub-directories.
(We can write it like "make $(obj)=<sub-dir>" with a shorthand.)
This means the current working directory is always the top
of the output directory.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Tested-by: Gerhard Sittig <gsi@denx.de>
This commit adjusts some files to use Kbuild.include.
- Use cc-option defined in Kbuild.include
(Delete cc-option in config.mk)
- Use cc-version defined in
(Delete cc-version in config.mk)
- Move binutils-version and dtc-version to Kbuild.include
by analogy to cc-version
This commit also adds srctree (same as SRCTREE)
to use Kbuild scripts.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
This commit moves suffix rules from config.mk
to scripts/Makefile.build, which will allow us
to switch smoothly to real Kbuild.
Note1:
post/lib_powerpc/fpu/Makefile has
its own rule to compile C sources.
We need to tweak it to keep the same behavior.
Note2:
There are two file2 with the same name:
arch/arm/lib/crt0.S and eamples/api/crt0.S.
To keep the same build behavior,
examples/api/Makefile also has to be treaked.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
This commit adds scripts/Makefile.host.tmp which will
be used in the next commit to convert makefiles
under tools/ directory to Kbuild style.
Notice this script, scripts/Makefile.host.tmp
is temporary.
When switching over to real Kbuild,
it will be replaced with scripts/Makefile.host of Linux Kernel.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
The support for COBJS, COBJS-y, SOBJS, SOBJS-y, GLCOBJS, GLSOBJS
from scripts/Makefile.build.
Going forward we need to use Kbuild style consistently.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
This patch tweaks scripts/Makefile.build to allow
the build system to descend into subdirectories like Kbuild.
To use this feature, use "obj-y += foo/" syntax.
Example:
obj-$(CONFIG_FOO) += foo/
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Simon Glass <sjg@chromium.org>
Every makefile in sub directories has common lines
at the top and the bottom.
This commit pushes the common parts into script/Makefile.build.
Going forward sub-makefiles only need to describe this part:
COBJS := ...
COBJS += ...
SOBJS := ...
But using obj-y is preferable to prepare for switching to Kbuild.
The conventional (non-Kbuild) Makefile style is still supported.
This is achieved by greping the Makefile before entering into it.
U-Boot conventional sub makefiles always include some other makefiles.
So the build system searches a line beginning with "include" keyword
in the makefile in order to distinguish which style it is.
If the Makefile include a "include" line, we assume it is a conventional
U-Boot style. Otherwise, it is treated as a Kbuild-style makefile.
With this tweak, we can switch sub-makefiles
from U-Boot style to Kbuild style little by little.
obj-y := foo/
syntax (descending into the sub directory) is not supportd yet.
It will be implemented in the upcomming commit.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Tom Rini <trini@ti.com>
