[RFC PATCH v4 1/2] arch: riscv: cpu: Add callback to init each core

[Rick Chen]

Hi Sean,

> On 4/13/21 12:12 AM, Rick Chen wrote:
> > Hi Sean
> >
> >> On 4/12/21 10:39 PM, Rick Chen wrote:
> >>> Hi Green,
> >>>
> >>>> From: Green Wan [mailto:green.wan at sifive.com]
> >>>> Sent: Monday, April 12, 2021 10:33 AM
> >>>> To: Sean Anderson
> >>>> Cc: Rick Chen; Rick Jian-Zhi Chen(陳建志); Bin Meng; U-Boot Mailing List; Paul Walmsley; Pragnesh Patel; Simon Glass; Atish Patra; Leo Yu-Chi Liang(梁育齊); Brad Kim
> >>>> Subject: Re: [RFC PATCH v4 1/2] arch: riscv: cpu: Add callback to init each core
> >>>>
> >>>> Hi Bin and Sean,
> >>>>
> >>>> While we keep the consistency of cache control discussion going, later
> >>>> today I'd like to send the v5 patch which is not directly relevant to
> >>>> cache control.
> >>>
> >>> I will prefer not to mix cache control issue into this patch.
> >>> Like I said, this callback is a init for all harts before lottery.
> >>
> >> Yes, but enabling caches is a very similar thing (this proposal even
> >> uses it to turn on caches, among other things). At the moment we have
> >> two calls to enable caches at almost the same time as what Green
> >> proposes. These calls only translate into work done on one platform. I
> >> think having one call (or perhaps two) for this purpose would help
> >> reduce codepaths across different platforms going forward.
> >>
> >
> > Maybe we can add two callbacks (early_lottery_init and
> > late_lottery_init) before and after lottery individually for all
> > scenarios.
>
> Yes, that is a possibility. But do we actually need that flexibility?
> This comes back around to my original question: why does ax25 disable
> cache on all harts before jumping to Linux?

clarify your above expressions:
only disable main hart (not all harts) before jumping to Linux.

Why you think it is a question to disable cache before jumping to Linux.
You can find many same cache flow in cleanup_before_linux of /arch/arm
Are they all the questions ?

Thanks,
Rick

>
> And of course, does this actually need to be done before the lottery?
>
> --Sean
>