The current arch implementation of memcpy cannot be called
from thumb code, because it does not use bx instructions on return.
This patch addresses that. Note, that this patch does not touch
the hot loop of memcpy, so performance is not affected.
Tested on MXS (arm926ejs) with and without thumb-mode enabled.
Signed-off-by: Klaus Goger <klaus.goger@theobroma-systems.com>
Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.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>
Today, we have cases where we wish to build all of U-Boot in Thumb2 mode for
various reasons. We also have cases where we only build SPL in Thumb2 mode due
to size constraints and wish to build the rest of the system in ARM mode. So
in this migration we introduce a new symbol as well, SPL_SYS_THUMB_BUILD to
control if we build everything or just SPL (or in theory, just U-Boot) in
Thumb2 mode.
Signed-off-by: Tom Rini <trini@konsulko.com>
Acked-by: Siarhei Siamashka <siarhei.siamashka@gmail.com>
Import unified.h from Linux kernel 4.4.6 , commit
0d1912303e54ed1b2a371be0bba51c384dd57326 . This header file contains
macros used in libgcc functions in Linux kernel on ARM and will be
needed for the libgcc sync.
Since unified.h defines the W(instr) macro, we must drop this from
the macro from memcpy.S , otherwise this triggers a warning about
symbol redefinition. In order to keep the changes to unified.h to
the minimum, tweak arch/arm/lib/Makefile such that it defines the
CONFIG_ARM_ASM_UNIFIED macro, which places .syntax unified into all
of the assembler files. This is mandatory.
Moreover, for Thumb2 build, define CONFIG_THUMB2_KERNEL macro if and
only if Thumb2 build is enabled. This macro is checked by unified.h
and toggles between ARM and Thumb2 variant of the instructions in the
assembler source files.
Finally, this patch defines __LINUX_ARM_ARCH__=N macro based on the
new CONFIG_SYS_ARM_ARCH Kconfig option. This macro selects between
more optimal and more dense codepaths which work on armv5 and newer
and less optimal codepaths which work on armv4 and possible armv3m.
Tegra2 needs the same special handling as it does in arch/arm/Makefile
to cater for the arm720t boot core.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Albert Aribaud <albert.u.boot@aribaud.net>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Tom Rini <trini@konsulko.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
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>
Resynchronize memcpy/memset with kernel 3.17 and build them in
Thumb2 mode (unified syntax). Those assembler files can be built
and linked in ARM mode too, however when calling them from Thumb2
built code, the stack got corrupted and the copy did not succeed
(the exact details have not been traced back). However, the Linux
kernel builds those files in Thumb2 mode. Hence U-Boot should
build them in Thumb2 mode too when CONFIG_SYS_THUMB_BUILD is set.
To build the files without warning, some assembler instructions
had to be replaced with their UAL compliant variant (thanks
Jeroen for this input).
To build the file in Thumb2 mode the implicit-it=always option need
to be set to generate Thumb2 compliant IT instructions where needed.
We add this option to the general AFLAGS when building for Thumb2.
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Stefan Agner <stefan@agner.ch>
In some cases (e.g. bootm with a elf payload which is already at the right
position) there is a in place copy of data to the same address. Catching this
saves some ms while booting.
Signed-off-by: Matthias Weisser <weisserm@arcor.de>
