[U-Boot] [PATCH 2/2] arm64: add better spin-table support

[Masahiro Yamada]

2016-06-18 18:40 GMT+09:00 Linus Walleij <linus.walleij at linaro.org>:
> On Fri, Jun 17, 2016 at 2:51 PM, Masahiro Yamada
> <yamada.masahiro at socionext.com> wrote:
>
>> There are two enable methods supported by ARM64 Linux; psci and
>> spin-table.  The latter is simpler and easier to use for quick SoC
>> bring-up.
>>
>> So, I used the spin-table for my first ARMv8 SoC porting, but I
>> found its support in U-Boot was poor.  It is true there exists a
>> code fragment for the spin code in arch/arm/cpu/armv8/start.S,
>> but I see some problems:
>
> Is part of the motivation for this approach to boot an ARMv8 system
> without using the ARM Trusted Firmware?
>
> Yours,
> Linus Walleij

Yes, exactly.

It would be the best choice
to switch over to PSCI with ATF in a long run,
but, I decided to use spin-table for the initial SoC bring-up
because of tight schedule.

If I use spin-table, I can keep the boot sequence very simple.


-- 
Best Regards
Masahiro Yamada