[RFC PATCH 1/3] ARM: Introduce ARM_SINGLE_ARMV7R for ARMv7-R platforms

[Vladimir Murzin]

On 6/30/22 10:22, Arnd Bergmann wrote:
> On Thu, Jun 30, 2022 at 10:36 AM Vladimir Murzin
> <vladimir.murzin at arm.com> wrote:
>>  config ARM_SINGLE_ARMV7M
>> -       def_bool !MMU
>> +       bool "ARM Cortex-M based platforms"
>>         select ARM_NVIC
>>         select AUTO_ZRELADDR
>>         select TIMER_OF
>> @@ -315,6 +320,18 @@ config ARM_SINGLE_ARMV7M
>>         select SPARSE_IRQ
>>         select USE_OF
>>
>> +config ARM_SINGLE_ARMV7R
>> +       bool "ARM Cortex-R based platforms"
>> +       select AUTO_ZRELADDR
>> +       select TIMER_OF
>> +       select COMMON_CLK
>> +       select CPU_V7
>> +       select NO_IOPORT_MAP
>> +       select SPARSE_IRQ
>> +       select USE_OF
>> +
> 
> I was actually hoping to eventually kill off the
> ARM_SINGLE_ARMV7M and ARCH_MULTIPLATFORM symbols
> and just select the other symbols from CONFIG_ARM directly, like
> 
>         select SPARSE_IRQ if !ARCH_RPC
>         select TIMER_OF if OF
>         select USE_OF if !(CPU_SA110 || CPU_SA1100)
>         select COMMON_CLK if !(ARCH_FOOTBRIDGE || ARCH_RPC)
>         ...
> 
> That can of course be done independently from your series, but
> it looks like ARM_SINGLE_ARMV7M and ARM_SINGLE_ARMV7R
> are mostly the same here, except for the ARM_NVIC selects that
> could be done by the platforms, and the CPU_V7/CPU_V7M
> difference that could be folded into the CPU selection menu.
> 

That sounds interesting! Moving NVIC into platforms looks straightforward,
yet CPU selection would require some surgery:
 - CPU_V7/CPU_V7M are not user selectable at the moment
 - We still need some hint from the platform if it supports more
   than one CPU variant, no?

Cheers
Vladimir

>        Arnd