Re: [PATCH v2 25/35] nds32: Build infrastructure

[Greentime Hu <green.hu@gmail.com>]

2017-11-30 15:52 GMT+08:00 Geert Uytterhoeven <geert@linux-m68k.org>:
> On Thu, Nov 30, 2017 at 6:48 AM, Greentime Hu <green.hu@gmail.com> wrote:
>> 2017-11-30 4:27 GMT+08:00 Arnd Bergmann <arnd@arndb.de>:
>>> On Wed, Nov 29, 2017 at 3:10 PM, Greentime Hu <green.hu@gmail.com> wrote:
>>>> 2017-11-29 19:57 GMT+08:00 Arnd Bergmann <arnd@arndb.de>:
>>>>> On Wed, Nov 29, 2017 at 12:39 PM, Greentime Hu <green.hu@gmail.com> wrote:
>> I think I can use this name "CPU_V3" for all nds32 v3 compatible cpu.
>> It will be implemented like this.
>>
>> config HWZOL
>>         bool "hardware zero overhead loop support"
>>         depends on CPU_D10 || CPU_D15
>>         default n
>>         help
>>           A set of Zero-Overhead Loop mechanism is provided to reduce the
>>           instruction fetch and execution overhead of loop-control instructions.
>>           It will save 3 registers($LB, $LC, $LE) for context saving if say Y.
>>           You don't need to save these registers if you can make sure your user
>>           program doesn't use these registers.
>>
>>           If unsure, say N.
>>
>> config CPU_CACHE_NONALIASING
>>         bool "Non-aliasing cache"
>>         depends on !CPU_N10 && !CPU_D10
>>         default n
>>         help
>>           If this CPU is using VIPT data cache and its cache way size is larger
>>           than page size, say N. If it is using PIPT data cache, say Y.
>>
>>           If unsure, say N.
>
> I still think it will be easier to revert the logic, and have
> CPU_CACHE_ALIASING.
>

Thanks Geert

I will implement it like this.

config HWZOL
        bool "hardware zero overhead loop support"
        depends on CPU_D10 || CPU_D15
        default n
        help
          A set of Zero-Overhead Loop mechanism is provided to reduce the
          instruction fetch and execution overhead of loop-control instructions.
          It will save 3 registers($LB, $LC, $LE) for context saving if say Y.
          You don't need to save these registers if you can make sure your user
          program doesn't use these registers.

          If unsure, say N.

config CPU_CACHE_ALIASING
        bool "Aliasing cache"
        depends on CPU_N10 || CPU_D10 || CPU_N13 || CPU_V3
        default y
        help
          If this CPU is using VIPT data cache and its cache way size is larger
          than page size, say Y. If it is using PIPT data cache, say N.

          If unsure, say Y.

choice
        prompt "CPU type"
        default CPU_V3
config CPU_N15
        bool "AndesCore N15"
config CPU_N13
        bool "AndesCore N13"
        select CPU_CACHE_ALIASING if ANDES_PAGE_SIZE_4KB
config CPU_N10
        bool "AndesCore N10"
        select CPU_CACHE_ALIASING
config CPU_D15
        bool "AndesCore D15"
config CPU_D10
        bool "AndesCore D10"
        select CPU_CACHE_ALIASING
config CPU_V3
        bool "AndesCore v3 compatible"
        select ANDES_PAGE_SIZE_8KB
endchoice