Re: [PATCH v5 REPOST 1/5] ARM: l2x0/pl310: Refactor Kconfig to be more maintainable

[Sascha Hauer <s.hauer@pengutronix.de>]

On Fri, Dec 16, 2011 at 04:35:28PM +0000, Dave Martin wrote:
> Making CACHE_L2X0 depend on (huge list of MACH_ and ARCH_ configs)
> is bothersome to maintain and likely to lead to merge conflicts.
> 
> This patch moves the knowledge of which platforms have a L2x0 or
> PL310 cache controller to the individual machines.  To enable this,
> a new MIGHT_HAVE_CACHE_L2X0 config option is introduced to allow
> machines to indicate that they may have such a cache controller
> independently of each other.
> 
> Boards/SoCs which cannot reliably operate without the L2 cache
> controller support will need to select CACHE_L2X0 directly from
> their own Kconfigs instead.  This applies to some TrustZone-enabled
> boards where Linux runs in the Normal World, for example.
> 
> Signed-off-by: Dave Martin <dave.martin@linaro.org>
> Acked-by: Anton Vorontsov <cbouatmailru@gmail.com>
>         (for cns3xxx)
> Acked-by: Tony Lindgren <tony@atomide.com>
>         (for omap)
> Acked-by: Shawn Guo <shawn.guo@linaro.org>
>         (for imx)

For i.MX:

Acked-by: Sascha Hauer <s.hauer@pengutronix.de>


> ---
>  arch/arm/Kconfig               |    8 ++++++++
>  arch/arm/mach-exynos/Kconfig   |    1 +
>  arch/arm/mach-omap2/Kconfig    |    1 +
>  arch/arm/mach-realview/Kconfig |    5 +++++
>  arch/arm/mach-vexpress/Kconfig |    1 +
>  arch/arm/mm/Kconfig            |   23 ++++++++++++++++-------
>  arch/arm/plat-mxc/Kconfig      |    1 +
>  7 files changed, 33 insertions(+), 7 deletions(-)
> 
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index 44789ef..16a4b9e 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -344,6 +344,7 @@ config ARCH_HIGHBANK
>  	select CPU_V7
>  	select GENERIC_CLOCKEVENTS
>  	select HAVE_ARM_SCU
> +	select MIGHT_HAVE_CACHE_L2X0
>  	select USE_OF
>  	help
>  	  Support for the Calxeda Highbank SoC based boards.
> @@ -361,6 +362,7 @@ config ARCH_CNS3XXX
>  	select CPU_V6K
>  	select GENERIC_CLOCKEVENTS
>  	select ARM_GIC
> +	select MIGHT_HAVE_CACHE_L2X0
>  	select MIGHT_HAVE_PCI
>  	select PCI_DOMAINS if PCI
>  	help
> @@ -381,6 +383,7 @@ config ARCH_PRIMA2
>  	select GENERIC_CLOCKEVENTS
>  	select CLKDEV_LOOKUP
>  	select GENERIC_IRQ_CHIP
> +	select MIGHT_HAVE_CACHE_L2X0
>  	select USE_OF
>  	select ZONE_DMA
>  	help
> @@ -633,6 +636,7 @@ config ARCH_TEGRA
>  	select GENERIC_GPIO
>  	select HAVE_CLK
>  	select HAVE_SCHED_CLOCK
> +	select MIGHT_HAVE_CACHE_L2X0
>  	select ARCH_HAS_CPUFREQ
>  	help
>  	  This enables support for NVIDIA Tegra based systems (Tegra APX,
> @@ -703,6 +707,7 @@ config ARCH_SHMOBILE
>  	select CLKDEV_LOOKUP
>  	select HAVE_MACH_CLKDEV
>  	select GENERIC_CLOCKEVENTS
> +	select MIGHT_HAVE_CACHE_L2X0
>  	select NO_IOPORT
>  	select SPARSE_IRQ
>  	select MULTI_IRQ_HANDLER
> @@ -904,6 +909,7 @@ config ARCH_U8500
>  	select CLKDEV_LOOKUP
>  	select ARCH_REQUIRE_GPIOLIB
>  	select ARCH_HAS_CPUFREQ
> +	select MIGHT_HAVE_CACHE_L2X0
>  	help
>  	  Support for ST-Ericsson's Ux500 architecture
>  
> @@ -914,6 +920,7 @@ config ARCH_NOMADIK
>  	select CPU_ARM926T
>  	select CLKDEV_LOOKUP
>  	select GENERIC_CLOCKEVENTS
> +	select MIGHT_HAVE_CACHE_L2X0
>  	select ARCH_REQUIRE_GPIOLIB
>  	help
>  	  Support for the Nomadik platform by ST-Ericsson
> @@ -973,6 +980,7 @@ config ARCH_ZYNQ
>  	select ARM_GIC
>  	select ARM_AMBA
>  	select ICST
> +	select MIGHT_HAVE_CACHE_L2X0
>  	select USE_OF
>  	help
>  	  Support for Xilinx Zynq ARM Cortex A9 Platform
> diff --git a/arch/arm/mach-exynos/Kconfig b/arch/arm/mach-exynos/Kconfig
> index 724ec0f..7f2347b 100644
> --- a/arch/arm/mach-exynos/Kconfig
> +++ b/arch/arm/mach-exynos/Kconfig
> @@ -17,6 +17,7 @@ choice
>  
>  config ARCH_EXYNOS4
>  	bool "SAMSUNG EXYNOS4"
> +	select MIGHT_HAVE_CACHE_L2X0
>  	help
>  	  Samsung EXYNOS4 SoCs based systems
>  
> diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig
> index 5034147..c841578 100644
> --- a/arch/arm/mach-omap2/Kconfig
> +++ b/arch/arm/mach-omap2/Kconfig
> @@ -44,6 +44,7 @@ config ARCH_OMAP4
>  	select CPU_V7
>  	select ARM_GIC
>  	select LOCAL_TIMERS if SMP
> +	select MIGHT_HAVE_CACHE_L2X0
>  	select PL310_ERRATA_588369
>  	select PL310_ERRATA_727915
>  	select ARM_ERRATA_720789
> diff --git a/arch/arm/mach-realview/Kconfig b/arch/arm/mach-realview/Kconfig
> index dba6d0c..3dd620f 100644
> --- a/arch/arm/mach-realview/Kconfig
> +++ b/arch/arm/mach-realview/Kconfig
> @@ -12,6 +12,7 @@ config REALVIEW_EB_A9MP
>  	bool "Support Multicore Cortex-A9 Tile"
>  	depends on MACH_REALVIEW_EB
>  	select CPU_V7
> +	select MIGHT_HAVE_CACHE_L2X0
>  	help
>  	  Enable support for the Cortex-A9MPCore tile fitted to the
>  	  Realview(R) Emulation Baseboard platform.
> @@ -21,6 +22,7 @@ config REALVIEW_EB_ARM11MP
>  	depends on MACH_REALVIEW_EB
>  	select CPU_V6K
>  	select ARCH_HAS_BARRIERS if SMP
> +	select MIGHT_HAVE_CACHE_L2X0
>  	help
>  	  Enable support for the ARM11MPCore tile fitted to the Realview(R)
>  	  Emulation Baseboard platform.
> @@ -39,6 +41,7 @@ config MACH_REALVIEW_PB11MP
>  	select CPU_V6K
>  	select ARM_GIC
>  	select HAVE_PATA_PLATFORM
> +	select MIGHT_HAVE_CACHE_L2X0
>  	select ARCH_HAS_BARRIERS if SMP
>  	help
>  	  Include support for the ARM(R) RealView(R) Platform Baseboard for
> @@ -51,6 +54,7 @@ config MACH_REALVIEW_PB1176
>  	select CPU_V6
>  	select ARM_GIC
>  	select HAVE_TCM
> +	select MIGHT_HAVE_CACHE_L2X0
>  	help
>  	  Include support for the ARM(R) RealView(R) Platform Baseboard for
>  	  ARM1176JZF-S.
> @@ -78,6 +82,7 @@ config MACH_REALVIEW_PBX
>  	bool "Support RealView(R) Platform Baseboard Explore"
>  	select ARM_GIC
>  	select HAVE_PATA_PLATFORM
> +	select MIGHT_HAVE_CACHE_L2X0
>  	select ARCH_SPARSEMEM_ENABLE if CPU_V7 && !REALVIEW_HIGH_PHYS_OFFSET
>  	select ZONE_DMA if SPARSEMEM
>  	help
> diff --git a/arch/arm/mach-vexpress/Kconfig b/arch/arm/mach-vexpress/Kconfig
> index 9311484..a8aefc8 100644
> --- a/arch/arm/mach-vexpress/Kconfig
> +++ b/arch/arm/mach-vexpress/Kconfig
> @@ -8,5 +8,6 @@ config ARCH_VEXPRESS_CA9X4
>  	select ARM_ERRATA_720789
>  	select ARM_ERRATA_751472
>  	select ARM_ERRATA_753970
> +	select MIGHT_HAVE_CACHE_L2X0
>  
>  endmenu
> diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig
> index 67f75a0..acb1c36 100644
> --- a/arch/arm/mm/Kconfig
> +++ b/arch/arm/mm/Kconfig
> @@ -816,14 +816,23 @@ config CACHE_FEROCEON_L2_WRITETHROUGH
>  	  Say Y here to use the Feroceon L2 cache in writethrough mode.
>  	  Unless you specifically require this, say N for writeback mode.
>  
> +config MIGHT_HAVE_CACHE_L2X0
> +	bool
> +	help
> +	  This option should be selected by machines which have a L2x0
> +	  or PL310 cache controller, but where its use is optional.
> +
> +	  The only effect of this option is to make CACHE_L2X0 and
> +	  related options available to the user for configuration.
> +
> +	  Boards or SoCs which always require the cache controller
> +	  support to be present should select CACHE_L2X0 directly
> +	  instead of this option, thus preventing the user from
> +	  inadvertently configuring a broken kernel.
> +
>  config CACHE_L2X0
> -	bool "Enable the L2x0 outer cache controller"
> -	depends on REALVIEW_EB_ARM11MP || MACH_REALVIEW_PB11MP || MACH_REALVIEW_PB1176 || \
> -		   REALVIEW_EB_A9MP || ARCH_IMX_V6_V7 || MACH_REALVIEW_PBX || \
> -		   ARCH_NOMADIK || ARCH_OMAP4 || ARCH_EXYNOS4 || ARCH_TEGRA || \
> -		   ARCH_U8500 || ARCH_VEXPRESS_CA9X4 || ARCH_SHMOBILE || \
> -		   ARCH_PRIMA2 || ARCH_ZYNQ || ARCH_CNS3XXX || ARCH_HIGHBANK
> -	default y
> +	bool "Enable the L2x0 outer cache controller" if MIGHT_HAVE_CACHE_L2X0
> +	default MIGHT_HAVE_CACHE_L2X0
>  	select OUTER_CACHE
>  	select OUTER_CACHE_SYNC
>  	help
> diff --git a/arch/arm/plat-mxc/Kconfig b/arch/arm/plat-mxc/Kconfig
> index b3a1f2b..b30708e 100644
> --- a/arch/arm/plat-mxc/Kconfig
> +++ b/arch/arm/plat-mxc/Kconfig
> @@ -20,6 +20,7 @@ config ARCH_IMX_V6_V7
>  	bool "i.MX3, i.MX6"
>  	select AUTO_ZRELADDR if !ZBOOT_ROM
>  	select ARM_PATCH_PHYS_VIRT
> +	select MIGHT_HAVE_CACHE_L2X0
>  	help
>  	  This enables support for systems based on the Freescale i.MX3 and i.MX6
>  	  family.
> -- 
> 1.7.4.1
> 
> 

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