[PATCH v3 1/3] Convert CONFIG_SYS_L2_PL310 to Kconfig

[Pali Rohár]

On Tuesday 09 August 2022 13:16:41 Marek Vasut wrote:
> On 8/9/22 12:58, Pali Rohár wrote:
> > On Tuesday 09 August 2022 12:07:00 Philip Oberfichtner wrote:
> > > This converts CONFIG_SYS_L2_PL310 to Kconfig.
> > ...
> > > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> > > index 949ebb46ba..dde06bdd96 100644
> > > --- a/arch/arm/Kconfig
> > > +++ b/arch/arm/Kconfig
> > > @@ -488,6 +488,10 @@ config TPL_SYS_THUMB_BUILD
> > >   	   density. For ARM architectures that support Thumb2 this flag will
> > >   	   result in Thumb2 code generated by GCC.
> > > +config SYS_L2_PL310
> > > +	bool "ARM PL310 L2 cache controller"
> > > +	help
> > > +	  Enable support for ARM PL310 L2 cache controller in U-Boot
> > >   config SYS_L2CACHE_OFF
> > >   	bool "L2cache off"
> > > diff --git a/arch/arm/mach-mvebu/include/mach/config.h b/arch/arm/mach-mvebu/include/mach/config.h
> > > index 4add0d9e10..0bba0a4cf9 100644
> > > --- a/arch/arm/mach-mvebu/include/mach/config.h
> > > +++ b/arch/arm/mach-mvebu/include/mach/config.h
> > > @@ -25,8 +25,6 @@
> > >   #define MV88F78X60 /* for the DDR training bin_hdr code */
> > >   #endif
> > > -#define CONFIG_SYS_L2_PL310
> > > -
> > >   #define MV_UART_CONSOLE_BASE		MVEBU_UART0_BASE
> > >   /* Needed for SPI NOR booting in SPL */
> > 
> > This option is required for mvebu SoC and is not user (de)-selectable.
> > So please do not define it in each individual mvebu board. It would make
> > it harder to introduce a new mvebu board into U-Boot. Instead enable it
> > for mvebu SoCs like it was before this change. It can be done e.g. by
> > "select" Kconfig keyword in mvebu Kconfig file.
> 
> Should it rather be 'default y if MVEBU' in that new PL310 Kconfig option ?

No, because this is just default value of this option and still allows
end-user to de-select this option.

"select" is IIRC the only way how to force Kconfig to always enable some
symbol without any option for end-user to disable it.

At least I do not know a way how CONFIG_SYS_L2_PL310 symbol could decide
that it is required for CONFIG_MVEBU. Just symbol CONFIG_MVEBU can
decide that it requires CONFIG_SYS_L2_PL310 symbol (and not in opposite
direction).