kbuild: use more subdir- for visiting subdirectories while cleaning

Documentation/kbuild/makefiles.rst suggests to use "archclean" for
cleaning arch/$(SRCARCH)/boot/, but it is not a hard requirement.

Since commit d92cc4d51643 ("kbuild: require all architectures to have
arch/$(SRCARCH)/Kbuild"), we can use the "subdir- += boot" trick for
all architectures. This can take advantage of the parallel option (-j)
for "make clean".

I also cleaned up the comments in arch/$(SRCARCH)/Makefile. The "archdep"
target no longer exists.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)

kbuild: rename hostprogs-y/always to hostprogs/always-y

In old days, the "host-progs" syntax was used for specifying host
programs. It was renamed to the current "hostprogs-y" in 2004.

It is typically useful in scripts/Makefile because it allows Kbuild to
selectively compile host programs based on the kernel configuration.

This commit renames like follows:

always -> always-y
hostprogs-y -> hostprogs

So, scripts/Makefile will look like this:

always-$(CONFIG_BUILD_BIN2C) += ...
always-$(CONFIG_KALLSYMS) += ...
...
hostprogs := $(always-y) $(always-m)

I think this makes more sense because a host program is always a host
program, irrespective of the kernel configuration. We want to specify
which ones to compile by CONFIG options, so always-y will be handier.

The "always", "hostprogs-y", "hostprogs-m" will be kept for backward
compatibility for a while.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

MIPS: boot: fix typo in 'vmlinux.lzma.its' target

Commit 92b34a976348 ("MIPS: boot: add missing targets for vmlinux.*.its")
fixed constant rebuild of *.its files on every make invocation, but due
to typo ("lzmo") it made no sense for vmlinux.lzma.its.

Fixes: 92b34a976348 ("MIPS: boot: add missing targets for vmlinux.*.its")
Cc: <stable@vger.kernel.org> # v4.19+
Signed-off-by: Alexander Lobakin <alobakin@dlink.ru>
[paulburton@kernel.org: s/invokation/invocation/]
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Rob Herring <robh@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org

kbuild: add $(BASH) to run scripts with bash-extension

CONFIG_SHELL falls back to sh when bash is not installed on the system,
but nobody is testing such a case since bash is usually installed.
So, shell scripts invoked by CONFIG_SHELL are only tested with bash.

It makes it difficult to test whether the hashbang #!/bin/sh is real.
For example, #!/bin/sh in arch/powerpc/kernel/prom_init_check.sh is
false. (I fixed it up)

Besides, some shell scripts invoked by CONFIG_SHELL use bash-extension
and #!/bin/bash is specified as the hashbang, while CONFIG_SHELL may
not always be set to bash.

Probably, the right thing to do is to introduce BASH, which is bash by
default, and always set CONFIG_SHELL to sh. Replace $(CONFIG_SHELL)
with $(BASH) for bash scripts.

If somebody tries to add bash-extension to a #!/bin/sh script, it will
be caught in testing because /bin/sh is a symlink to dash on some major
distributions.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

kbuild: add real-prereqs shorthand for $(filter-out FORCE,$^)

In Kbuild, if_changed and friends must have FORCE as a prerequisite.

Hence, $(filter-out FORCE,$^) or $(filter-out $(PHONY),$^) is a common
idiom to get the names of all the prerequisites except phony targets.

Add real-prereqs as a shorthand.

Note:
We cannot replace $(filter %.o,$^) in cmd_link_multi-m because $^ may
include auto-generated dependencies from the .*.cmd file when a single
object module is changed into a multi object module. Refer to commit
69ea912fda74 ("kbuild: remove unneeded link_multi_deps"). I added some
comment to avoid accidental breakage.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Rob Herring <robh@kernel.org>

MIPS: boot: merge build rules of vmlinux.*.itb by using pattern rule

Merge the build rule of vmlinux.{gz,bz2,lzma,lzo}.itb, and also move
'targets' close to the related code.

[paul.burton@mips.com:
- Remove leading tabs from assignments to itb_addr_cells, since after
this patch moves the additions to the 'targets' variable the
assignments to itb_addr_cells wound up being treated as part of the
uImage rule above them, causing the .its to incorrectly be generated
with empty ADDR_CELLS.]

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Patchwork: https://patchwork.linux-mips.org/patch/19095/
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: linux-kernel@vger.kernel.org

MIPS: boot: add missing targets for vmlinux.*.its

The build rule of vmlinux.*.its is invoked by $(call if_changed,...)
but it always rebuilds the target needlessly due to missing targets.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Patchwork: https://patchwork.linux-mips.org/patch/19092/
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: linux-kernel@vger.kernel.org

MIPS: boot: fix build rule of vmlinux.its.S

As Documentation/kbuild/makefile.txt says, it is a typical mistake
to forget the FORCE prerequisite for the rule invoked by if_changed.

Add the FORCE to the prerequisite, but it must be filtered-out from
the files passed to the 'cat' command. Because this rule generates
.vmlinux.its.S.cmd, vmlinux.its.S must be specified as targets so
that the .cmd file is included.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Patchwork: https://patchwork.linux-mips.org/patch/19097/
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: linux-kernel@vger.kernel.org

MIPS: boot: do not include $(cpp_flags) for preprocessing ITS

$(CPP) is used here to perform macro replacement in ITS. Do not
pass $(cpp_flags) because it pulls in more options for dependency
file generation etc. but none of which is necessary here. ITS files
do not include any header file, so $(call if_change,...) is enough.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Patchwork: https://patchwork.linux-mips.org/patch/19093/
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: linux-kernel@vger.kernel.org

Revert "MIPS: boot: Define __ASSEMBLY__ for its.S build"

This reverts commit 0f9da844d87796ac31b04e81ee95e155e9043132.

It is true that commit 0f9da844d877 ("MIPS: boot: Define __ASSEMBLY__
for its.S build") fixed the build error, but it should not have
defined __ASSEMBLY__ just for textual substitution in arbitrary data.
The file is image tree source in this case, but the purpose of using
CPP is to replace some macros.

I merged a better solution, commit a95b37e20db9 ("kbuild: get
<linux/compiler_types.h> out of <linux/kconfig.h>"). The original
fix-up is no longer needed.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Patchwork: https://patchwork.linux-mips.org/patch/19096/
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: linux-kernel@vger.kernel.org

MIPS: boot: Define __ASSEMBLY__ for its.S build

The MIPS %.its.S compiler command did not define __ASSEMBLY__, which meant
when compiler_types.h was added to kconfig.h, unexpected things appeared
(e.g. struct declarations) which should not have been present. As done in
the general %.S compiler command, __ASSEMBLY__ is now included here too.

The failure was:

Error: arch/mips/boot/vmlinux.gz.its:201.1-2 syntax error
FATAL ERROR: Unable to parse input tree
/usr/bin/mkimage: Can't read arch/mips/boot/vmlinux.gz.itb.tmp: Invalid argument
/usr/bin/mkimage Can't add hashes to FIT blob

Reported-by: kbuild test robot <lkp@intel.com>
Fixes: 28128c61e08e ("kconfig.h: Include compiler types to avoid missed struct attributes")
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MIPS: Allow platform to specify multiple its.S files

In preparation for splitting arch/mips/generic/vmlinux.its.S into
multiple files such that it doesn't become a conflict magnet as boards
are added, allow platforms to specify a list of image tree source files
which will be concatenated to form the final source used to build the
image tree.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16938/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: .its targets depend on vmlinux

The .its targets require information about the kernel binary, such as
its entry point, which is extracted from the vmlinux ELF. We therefore
require that the ELF is built before the .its files are generated.
Declare this requirement in the Makefile such that make will ensure this
is always the case, otherwise in corner cases we can hit issues as the
.its is generated with an incorrect (either invalid or stale) entry
point.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: cf2a5e0bb4c6 ("MIPS: Support generating Flattened Image Trees (.itb)")
Cc: linux-mips@linux-mips.org
Cc: stable <stable@vger.kernel.org> # v4.9+
Patchwork: https://patchwork.linux-mips.org/patch/16179/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: generic: Introduce generic DT-based board support

Introduce a "generic" platform, which aims to be board-agnostic by
making use of device trees passed by the boot protocol defined in the
MIPS UHI (Universal Hosting Interface) specification. Provision is made
for supporting boards which use a legacy boot protocol that can't be
changed, but adding support for such boards or any others is left to
followon patches.

Right now the built kernels expect to be loaded to 0x80100000, ie. in
kseg0. This is fine for the vast majority of MIPS platforms, but
nevertheless it would be good to remove this limitation in the future by
mapping the kernel via the TLB such that it can be loaded anywhere & map
itself appropriately.

Configuration is handled by dynamically generating configs using
scripts/kconfig/merge_config.sh, somewhat similar to the way powerpc
makes use of it. This allows for variations upon the configuration, eg.
differing architecture revisions or subsets of driver support for
differing boards, to be handled without having a large number of
defconfig files.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14353/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Support generating Flattened Image Trees (.itb)

Add support for generating kernel images in the Flattened Image Tree
(.itb) format as supported by U-Boot. This format is essentially a
Flattened Device Tree binary containing images (kernels, DTBs, ramdisks)
and configurations which link those images together. The big advantages
of FIT images over the uImage format are:

- We can include FDTs in the kernel image in a way that the bootloader
can extract it & manipulate it before providing it to the kernel.
Thus we can ship FDTs as part of the kernel giving us the advantages
of being able to develop & maintain the DT within the kernel tree,
but also have the benefits of the bootloader being able to
manipulate the FDT. Example uses for this would be to inject the
kernel command line into the chosen node, or to fill in the correct
memory size.

- We can include multiple configurations in a single kernel image.
This means that a single FIT image can, given appropriate
bootloaders, be booted on different boards with the bootloader
selecting an appropriate configuration & providing the correct FDT
to the kernel.

- We can support a multitude of hashes over the data.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14352/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: boot: Provide more uImage options

Allow more compression algorithms as well as uncompressed uImage.bin
to be generated. An uncompressed image might be useful to rule out
problems in the decompression code in the bootloader or even speed
up the boot process at the expense of a bigger uImage file.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9271/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Add uImage build target

Add a uImage build target for MIPS, which builds uImage.gz (a U-Boot
image of vmlinux.bin.gz), and then symlinks it to uImage. This allows
for the use of other compression algorithms in future, and is how a few
other architectures do it.

It's enabled conditionally on load-y >= 0xffffffff80000000 which
hopefully allows 64bit kernels to also work as long as the load and
entry address can be represented by the 32bit addresses in the U-Boot
image format.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5795/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Whitespace cleanup.

Having received another series of whitespace patches I decided to do this
once and for all rather than dealing with this kind of patches trickling
in forever.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Refactor arch/mips/boot/Makefile

- remove stuff that is not needed
VMLINUX assignment, all: rule
- use hostprogs-y for the host program
- use kbuild rules for the three targets - to beautify output
- drop clean-files - it is no longer needed
- simplify arch/mips/Makefile when calling targets in boot/Makefile

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
To: linux-mips <linux-mips@linux-mips.org>
To: Wu Zhangjin <wuzhangjin@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/1303/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Move vmlinux.ecoff to arch/mips/boot

It moves to the same directory as the boot files in other formats.

Signed-off-by: Yoichi Yuasa <yuasa@linux-mips.org>
Cc: linux-mips <linux-mips@linux-mips.org>
Patchwork: http://patchwork.linux-mips.org/patch/796/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Remove addinitrd and CONFIG_PROBE_INITRD_HEADER

Addinitrd has been superseded by initramfs ages ago.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

[MIPS] Fix archhelp.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

commit 1858f72fa2e2f63e62114a9bd40c8e68468d8c5e
Author: Ralf Baechle <ralf@linux-mips.org>
Date: Fri Jul 22 05:46:02 2005 +0000

New build target vmlinux.bin build raw binary image for Qemu.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!