Choosing big-endian vs little-endian kernels in Kconfig has not worked
correctly since the introduction of CONFIG_ARCH_MULTIPLATFORM a long
time ago.
The problems is that CONFIG_BIG_ENDIAN depends on
ARCH_SUPPORTS_BIG_ENDIAN, which can set by any one platform
in the config, but would actually have to be supported by all
of them.
This was mostly ok for ARMv6/ARMv7 builds, since these are BE8 and
tend to just work aside from problems in nonportable device drivers.
For ARMv4/v5 machines, CONFIG_BIG_ENDIAN and CONFIG_ARCH_MULTIPLATFORM
were never set together, so this was disabled on all those machines
except for IXP4xx.
As IXP4xx can now become part of ARCH_MULTIPLATFORM, it seems better to
formalize this logic: all ARMv4/v5 platforms get an explicit dependency
on being either big-endian (ixp4xx) or little-endian (the rest). We may
want to fix ixp4xx in the future to support both, but it does not work
in LE mode at the moment.
For the ARMv6/v7 platforms, there are two ways this could be handled
a) allow both modes only for platforms selecting
'ARCH_SUPPORTS_BIG_ENDIAN' today, but only LE mode for the
others, given that these were added intentionally at some
point.
b) allow both modes everwhere, given that it was already possible
to build that way by e.g. selecting ARCH_VIRT, and that the
list is not an accurate reflection of which platforms may or
may not work.
Out of these, I picked b) because it seemed slighly more logical
to me.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
It is possible to build MMU-less kernels for Cortex-M base
microcrontrollers as well as a couple of older platforms that
have not been converted to CONFIG_ARCH_MULTIPLATFORM,
specifically ep93xx, footbridge, dove, sa1100 and s3c24xx.
It seems unlikely that anybody has tested those configurations
in recent years, as even building them is frequently broken.
A patch I submitted caused another build time regression
in this configuration. I sent a patch for that, but it seems
better to also remove the option entirely, leaving ARMv7-M
as the only supported Arm NOMMU target for simplicity.
A couple of platforms have dependencies on CONFIG_MMU, those
can all be removed now. Notably, mach-integrator tries to
support MMU-less CPU cores, but those have not actually been
selectable for a long time.
This addresses several build failures in randconfig builds that
have accumulated over the years.
Cc: Vladimir Murzin <vladimir.murzin@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change the Kconfig option logic to fullfil with the current approach.
A new Kconfig option is added, CONFIG_NSPIRE_TIMER and is selected by the
platform. Then the clocksource's Kconfig is changed to make this option
selectable by the user if the COMPILE_TEST option is set. Otherwise, it is
up to the platform's Kconfig to select the timer.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Multi-platform requires various kconfig options to be selected, so
platforms don't need to select them individually.
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
This patch adds support for the TI-Nspire platform.
Changes between v1 and v2:
* Added GENERIC_IRQ_CHIP to platform Kconfig
Signed-off-by: Daniel Tang <dt.tangr@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Arnd Bergmann