Merge branch 'for-next/sandbox-compile-test'

Merge branch 'for-next/misc'

sandbox: define CONFIG_64BIT as appropriate ...

All 64-bit architectures are supposed to define CONFIG_64BIT to support
the relevant 64-bit MMIO accessors. The sandbox architecture is a bit
of a special case, because barebox uses the toolchain default and
doesn't force a bitness. Add 64BIT as promptless symbol, which reflects
the pointer size of the target platform.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

scripts: import Linux Kconfig.include ...

With this include, we can have goodies like $(cc-option ...) and
$(success ...) inside our Kconfig files.

gcc-version also now becomes available. While unused for now, it can
allow us to selectively turn on warnings on new GCC versions, which
were previously disabled because of their too high false positive rate.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

scripts: .gitignore: ignore mvebuimg binary ...

If selected, we generate a mvebuimg binary that should be ignored by
version control. Add .gitignore entry to do so.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

kbuild: switch over to thin archive ...

Starting v4.13, Linux always uses thin archive instead of relocatable
ELF to combine builtin objects.

The thin archive is basically a text file that only contains paths to
object files.

As Linux commit 98ced886dd79 mentioned, this has a lot of benefits:

 - save disk space for builds

 - speed-up building a little

 - fix some issues when liking a giant executable (for example,
   allyesconfig on ARM Linux)

 - work better with dead code elimination

The last one is important for barebox because pbl highly relies on the
dead code elimination (-f{function,data}-sections and --gc-sections)
dropping symbols that are unreachable from the linker's entry point.
The dead code elimination does not work if the same symbol names are
used in the pevious incremental link mechanism because the same name
symbols all go into the same section.

Commit a83c97f2a406 ("ARM: socfpga: generate smaller images when
multiple boards are selected") worked around it by giving a dedicate
section to each of the same name symbols. This workaround can go away.

built-in.o was renamed to built-in.a since it is now an archive.
built-in-pbl.o was renamed to built-in.pbl.a for consistency.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

kbuild: unify barebox and pbl build commands ...

The current Linux uses the unified build command for built-in objects
and module objects. This is possible because part-of-module is set to
y when the target is being built for a module. If so, quiet_modtag is
set to [M], and modkern_cflags is set to KBUILD_CFLAGS_MODULE instead
of KBUILD_CFLAGS_KERNEL.

Currently, barebox uses a separate build command for pbl, but the
difference between cmd_cc_o_c and cmd_pbl_cc_o_c is just
"-D__PBL__ $(PBL_CPPFLAGS)".

By using the same approach as Linux, they can be unified.

Set part-of-pbl flag to y when the target is being built for pbl.
Merge cmd_as_o_S and cmd_link_o_target as well.

This also changes the shortlog style as follows:

  PBLCC  ->  CC [P]
  PBLAS  ->  AS [P]
  PBLLD  ->  LD [P]

This is more consistent with the policy in the Linux build system.

In Linux, a capital letter enclosed square blackets indicates which
target the object is being built for.

  CC      object built for built-in
  CC [M]  object built for modules
  CC [U]  object built for userspace (proposed for Linux 5.8-rc1)

The idea behind this is we use the same compiler $(CC) for them.
Only the difference is the compiler flags. On the other hand, host
programs are compiled by a different tool, $(HOSTCC), hence the
shortlog is 'HOSTCC'.

Barebox supports module builds (it seems), but the [P] notation does
not conflict with [M] because pbl has a limited memory footprint.
We never expect pbl can support the module feature.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

kbuild: resync modkern_{c, a}flags and quiet_modtag with Linux 5.7-rc6 ...

The latest Linux calculates them more simply; part-of-module is set
when the target is being built for a module.

Also, rename real-objs-{y,m} to real-obj-{y,m}.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

kbuild: append $(bbenv-y) to obj-y earlier ...

You can save one line.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

kbuild: resync mkdir code with Linux 5.7-rc6 ...

Kbuild automatically creates the output directories for O= builds.
Previously it called mkdir too much. Linux optimized this a lot.
Let's import the outcome so it works faster.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

kbuild: remove obj-dtb-y, pbl-dtb-y, lwl-dtb-y syntax ...

The embedded DTBs are compiled by the chain of pattern rules as follows:

  %.dts -> %.dtb -> %.dtb.S -> %.dtb.o       for barebox proper
  %.dts -> %.dtb -> %.dtb.S -> %.dtb.pbl.o   for pbl

Barebox introduced {obj,pbl,lwl}-dtb-y syntax to put the intermediate
files into extra-y. The purposes of doing so were:

 [1] prevent GNU Make from deleting the intermediate files
 [2] include .*.cmd files

In contrast, Linux does not use a special syntax for embedding DTBs
into the kernel.

For example, as you see in arch/sh/boot/dts/Makefile of Linux 5.6,

   obj-y += <basename>.dtb.o

... just works.

This is because scripts/Kbuild.include specifies .SECONDARY to cater
to [1], and scripts/Makefile.build adds the intermediates to 'targets'
to deal with [2].

Barebox had already imported the same code from Linux, so you can use
obj-y instead of obj-dtb-y, like Linux.

pbl-dtb-y and lwl-dtb-y are barebox-specific cases, so I added the
%.dtb.pbl.o pattern to intermediate_targets.

Going forward, please use obj-y, pbl-y, or lwl-y.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

kbuild: rename pbl object pbl-*.o to *.pbl.o ...

Currently, pbl objects are output to:

  <directory-path>/pbl-<basename>.o

This commit changes as follows:

  <directory-path>/<basename>.pbl.o

The motivation is not only to get rid of the ugly code introduced by
commit 257abdaa36c8 ("Do not rm the path from pbl-y target"), but also
to make it easier to remove obj-dtb-y, pbl-dtb-y, lwl-dtb-y syntax in
the next commit.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Merge branch 'for-next/stm32'

Merge branch 'for-next/misc'

Merge branch 'for-next/kconfig'

Merge branch 'for-next/kbuild'

scripts: add stm32image to .gitignore ...

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

kbuild: resync top Makefile, mkmakefile, tags.sh with Linux 5.7-rc4 ...

The prologue of the build system is not specific to Linux or Barebox.
Paritially resync with Linux 5.7-rc4

- In Linux, $(objtree) is always '.', and $(srctree) might be relative.
  I am keeping both absolute for now to avoid unexpected breakage.

- I did not resync single target for now. We need to touch
  Makefile.build a lot if we want to resync it.

- 'export CDPATH=' is Barebox-only code, which was added by
  commit 6cc8d0544658 ("Makefile: disable CDPATH"). Keep it.

- KBUILD_SRC no longer exists in the upstream Linux. I replaced it
  with building_out_of_srctree.

- scripts/mkmakefile does not contain anything specific to Linux or
  Barebox. Resync it with Linux 5.7-rc4

- scripts/tags was imported from Linux 3.6 with some cherry-picks on
  top of that. Resync it with Linux 5.7-rc4

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

scripts: bareboximd: fix write_file error handling ...

write will never return 0 on POSIX conformant systems. Remove this error
path.
Also, close the file on error.

Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

kbuild: sync scripts/Kbuild.include with Linux 5.7-rc2 ...

More random cherry-picks for scripts/Kbuild.include

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

kbuild: sync if_changed and friends with Linux 5.7-rc2 ...

Resync cmd, if_change, if_changed_dep, and if_changed_rule.

Clean up the users of if_changed_rule.

I deleted the modversions rule. It is dead code because barebox
does not define CONFIG_MODVERSIONS. It does not work without
scripts/genksyms/ anyway.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

kbuild: sync filechk rule with Linux 5.7-rc2 ...

The 'filechk' in the latest Linux works more simply, reliably.

- Do not show CHK every time
- Delete the *.tmp file when the filechk_$(1) fails
- Do not open the first prerequisite. This is unneeded in most cases.

I deleted pointeless dependency on Makefile.

Also delete the meaningless assignment to 'targets' because filechk
does not generate .cmd file.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

kbuild: add $(always-y) to 'targets' ...

I missed to sync this line in commit 421108c51da4 ("kbuild: rename
hostprogs-y/always to hostprogs/always-y").

Since then, the files in always(-y) are needlessly rebuilt.

Fixes: 421108c51da4 ("kbuild: rename hostprogs-y/always to hostprogs/always-y")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

scripts: imd: fix uninitialized variable read ...

Errors are propagated in the loop and ret is never set. Remove it.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

scripts: kconfig-lint.py: extend for undefined symbol detection ...

Extend the script by some code from the official list_undefined.py example[1]
to further detect symbols we are using, but haven't defined anywhere.

[1]: https://github.com/ulfalizer/Kconfiglib/blob/35a60b7/examples/list_undefined.py

Signed-off-by: Ahmad Fatoum <ahmad@a3f.at>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

scripts: import Zephyr scripts/kconfig/lint.py into barebox ...

This kconfig linter can do some useful analysis to find problems
in our Kconfig files. Import it into barebox source tree with the
changes necessary to be usable.

The results of running it should be taken with a grain of salt and
verified with grep.

Signed-off-by: Ahmad Fatoum <ahmad@a3f.at>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

kbuild: use $(SRCARCH) to point to the arch directory ...

A couple of arch directories in Linux are biarch, that is, a single
arch/*/ directory supports both 32-bit and 64-bit.

In old days of Linux, they started as separated directories.
arm/arm64 is the exceptional case, but the other architectures were
unified.

e.g.)

  arch/i386, arch/x86_64    ->  arch/x86
  arch/sh, arch/sh64        ->  arch/sh
  arch/sparc, arch/sparc64  ->  arch/sparc

Linux commit 6752ed90da03 ("Kbuild: allow arch/xxx to use a different
source path") introduced SRCARCH to point to the arch directory, still
allowing to pass in the former ARCH=i386 or ARCH=x86_64.

The top Makefile in Linux converts ARCH to SRCARCH as follows:

  # Additional ARCH settings for x86
  ifeq ($(ARCH),i386)
          SRCARCH := x86
  endif
  ifeq ($(ARCH),x86_64)
          SRCARCH := x86
  endif

So, if you follow the upstream Kbuild convention, using arch/$(SRCARCH)
is the correct way to point to the arch directory.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

modpost: sync mk_elfconfig.c with Linux 5.7-rc2 ...

Just get rid of the argument $(ARCH), then hardcode MODULE_SYMBOL_PREFIX.
This should have no impact because none of v850, h8300, blackfin is
supported by barebox.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

kconfig: update to Linux 5.7-rc2 ...

The previous sync was Linux 5.5. This updates Kconfig to Linux 5.7-rc2.

Highlights:

 - add yes2modconfig and mod2yesconfig, which are useful for coping with
   syzbot configs in Linux

 - remove include/config/tristate.conf

 - show more precise help

 - fix various issues of 'make xconfig'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

kbuild: prefix compiler flag variables with KBUILD_ ...

In old days, Linux also used to use well-known variables such CFLAGS,
CPPFLAGS, etc.

They were prefixed with KBUILD_ presumably for preventing users from
overriding them accidentally.

Rename as follows:
  CFLAGS          ->  KBUILD_CFLAGS
  AFLAGS          ->  KBUILD_AFLAGS
  CPPFLAGS        ->  KBUILD_CPPFLAGS
  LDFLAGS         ->  KBUILD_LDFLAGS
  HOSTCFLAGS      ->  KBUILD_HOSTCFLAGS
  HOSTCXXFLAGS    ->  KBUILD_HOSTCXXFLAGS
  HOSTLDFLAGS     ->  KBUILD_HOSTLDFLAGS
  HOST_LOADLIBES  ->  KBUILD_HOSTLDLIBS

HOSTCFLAGS, HOSTCXXFLAGS, HOSTLDFLAGS, HOSTLDLIBS are re-used to allow
users to pass-in additional flags to the host compiler.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>