Based on the following Linux commits:

 - 54a702f70589 ("kbuild: mark $(targets) as .SECONDARY and remove
   .PRECIOUS markers")

 - 8e9b61b293d9 ("kbuild: move .SECONDARY special target to
   Kbuild.include")

GNU Make automatically deletes intermediate files that are updated
in a chain of pattern rules.

Example 1) %.dtb.o <- %.dtb.S <- %.dtb <- %.dts
Example 2) %.o <- %.c <- %.c_shipped

A couple of makefiles mark such targets as .PRECIOUS to prevent Make
from deleting them, but the correct way is to use .SECONDARY.

  .SECONDARY
    Prerequisites of this special target are treated as intermediate
    files but are never automatically deleted.

  .PRECIOUS
    When make is interrupted during execution, it may delete the target
    file it is updating if the file was modified since make started.
    If you mark the file as precious, make will never delete the file
    if interrupted.

Both can avoid deletion of intermediate files, but the difference is
the behavior when Make is interrupted; .SECONDARY deletes the target,
but .PRECIOUS does not.

The use of .PRECIOUS is relatively rare since we do not want to keep
partially constructed (possibly corrupted) targets.

.SECONDARY with no prerequisites causes all targets to be treated as
secondary. This agrees the policy of Kbuild.

scripts/Kbuild.include seems a suitable place to add it because it is
included from almost all sub-makes.

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

Currently the OBJCOPYFLAGS are cleared when assigning "-O srec"
or "-O binary" for standalone programs. All flags set by arch-specific
Makefiles are lost. This is bad if an arch demands arch-specific
flags for the objcopy step.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Tom Rini <trini@konsulko.com>

Introduce a new Makefile variable for passing LDFLAGS to standalone
programs. Currently the variable CONFIG_STANDALONE_LOAD_ADDR is
misued on some archs to pass a specific linker script.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Rick Chen <rick@andestech.com>

When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>

There was for long time no activity in the mpx5xxx area.
We need to go further and convert to Kconfig, but it
turned out, nobody is interested anymore in mpc5xxx,
so remove it.

Signed-off-by: Heiko Schocher <hs@denx.de>

There was for long time no activity in the 8260 area.
We need to go further and convert to Kconfig, but it
turned out, nobody is interested anymore in 8260,
so remove it.

Signed-off-by: Heiko Schocher <hs@denx.de>

There was for long time no activity in the 8xx area.
We need to go further and convert to Kconfig, but it
turned out, nobody is interested anymore in 8xx,
so remove it (with a heavy heart, knowing that I remove
here the root of U-Boot).

Signed-off-by: Heiko Schocher <hs@denx.de>

When building a Thumb-1-only target with CONFIG_SYS_THUMB_BUILD,
some files fail to build, most of the time because they include
mcr instructions, which only exist for Thumb-2.

This patch introduces a Kconfig option CONFIG_THUMB2 and uses
it to select between Thumb-2 and ARM mode for the aforementioned
files.

Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>

Files added $(extra-) are removed by "make clean".
Besides, wildcard "*.srec *.bin" is simpler.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>

In case of multilib-enabled toolchains if default architecture differ from
the one examples are being built for linker will fail to link example object
files with libgcc of another (non-compatible) architecture.

Interesting enough for years in main Makefile we used CFLAGS/c_flags for this
but not for examples.

So fixing it now.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>

Cc: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Tom Rini <trini@ti.com>
Cc: Wolfgang Denx <wd@denx.de>
Acked-by: WOlfgang Denk <wd@denx.de>
Acked-by: Masahiro Yamada <yamada.m@jp.panasonic.com>