On Thu, Jun 21, 2018 at 05:59:06PM +0200, Geert Uytterhoeven wrote:
> "ARM multiplatform" has actually two meanings:
> 1. It groups platforms that follow the "ARM multiplatform" software
> framework,
> 2. It allows to build a single kernel that can be booted on multiple
> platforms.
>
> Currently support for XIP and/or NOMMU cannot be enabled on platforms
> that follow the "ARM multiplatform" framework, without duplicating their
> machine selection logic under a new Kconfig symbol. As (in theory) all
> platforms can be used with XIP and/or NOMMU, this is not sustainable.
>
> Hence clarify the meaning of ARCH_MULTIPLATFORM:
> 1. Replace "multiple platforms" by "common platform", as it allows to
> select one or more platforms adhering to the common framework,
> 2. Note that a single kernel may not boot on all platforms if XIP or
> NOMMU is enabled.
>
> Signed-off-by: Geert Uytterhoeven <geert+rene...@glider.be>
> ---
> References:
> - "[PATCHv4 0/4] arm/versatile: no-MMU support"
>
> (http://lists.infradead.org/pipermail/linux-arm-kernel/2018-June/584555.html)
>
> - "[PATCH 0/2] ARM: ARMv7 (with MMU) XIP without ARCH_MULTIPLATFORM"
>
> (http://lists.infradead.org/pipermail/linux-arm-kernel/2017-February/486835.html)
>
> arch/arm/Kconfig | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index 54eeb8d00bc62a9f..6b286c018cf748c7 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -329,7 +329,7 @@ choice
> default ARCH_MULTIPLATFORM if MMU
>
> config ARCH_MULTIPLATFORM
> - bool "Allow multiple platforms to be selected"
> + bool "Common platforms (\"multiplatform\")"
> depends on MMU
> select ARM_HAS_SG_CHAIN
> select ARM_PATCH_PHYS_VIRT
> @@ -342,6 +342,13 @@ config ARCH_MULTIPLATFORM
> select PCI_DOMAINS if PCI
> select SPARSE_IRQ
> select USE_OF
> + help
> + Support for systems implemented using the common "multiplatform"
> + framework.
> +
> + Unless specialized options depending on intimate platform
> + details, like XIP or NOMMU, are enabled, this allows to build a
> + single kernel that boots on multiple platforms.
Hi Geert,
I wonder if this might be slightly clearer:
Unless specialized options that depend on intimate platform
details, such as XIP and NOMMU, are enabled, this allows building
a single kernel that boots on multiple platforms.
>
> config ARM_SINGLE_ARMV7M
> bool "ARMv7-M based platforms (Cortex-M0/M3/M4)"
> --
> 2.17.1
>
