[PATCH 2/2] riscv: sbi: Move sbi_probe_extension() out of CONFIG_SBI_V01

[Rick Chen]

Hi Atish

Atish Patra <atishp at atishpatra.org> 於 2020年6月3日 週三 上午2:32寫道：
>
> On Mon, Jun 1, 2020 at 2:09 AM Bin Meng <bmeng.cn at gmail.com> wrote:
> >
> > Hi Rick,
> >
> > On Mon, Jun 1, 2020 at 5:08 PM Rick Chen <rickchen36 at gmail.com> wrote:
> > >
> > > Hi Bin
> > >
> > > > > From: Bin Meng [mailto:bmeng.cn at gmail.com]
> > > > > Sent: Wednesday, May 27, 2020 5:05 PM
> > > > > To: Rick Jian-Zhi Chen(陳建志); U-Boot Mailing List
> > > > > Cc: Atish Patra; Bin Meng
> > > > > Subject: [PATCH 2/2] riscv: sbi: Move sbi_probe_extension() out of CONFIG_SBI_V01
> > > > >
> > > > > From: Bin Meng <bin.meng at windriver.com>
> > > > >
> > > > > sbi_probe_extension() is an API defined in SBI v0.2, not v0.1.
> > > > >
> > > > > Fixes 7e249bc13aaf: ("riscv: Move all SMP related SBI calls to SBI_v01")
> > > > > Signed-off-by: Bin Meng <bin.meng at windriver.com>
> > > > > ---
> > > >
> > > > Reviewed-by: Rick Chen <rick at andestech.com>
> > > >
> > >
> > > BTW, it seem look like sbi_remote_fence_i, sbi_remote_sfence_vma and
> > > sbi_remote_sfence_vma_asid
> > > are all can be used no mater in SBI_V01 or SBI_V02. Because you have
> > > distinguished them in sbi.h
> >
> > No these calls are different and not compatible between SBI_V01 and SBI_V02.
> >
>
> In addition to that, U-Boot proper enables SMP only for SBI_V01
> because U-Boot doesn't need
> boot all the cores if the supervisor OS & SBI provider supports SBI
> v0.2 with HSM.
>
> Starting with OpenSBI v0.7 & Linux kernel 5.7 supports both. Thus,
> there is no advantage in adding
> redundant code in a generic path that is never going to be used.
>
> Any SBI provider that only supports SBI v0.1, the user can fall back
> to SBI_V01 config.

Thanks for your explanation.

Regards,
Rick

> > See commit 7e249bc13aaf: ("riscv: Move all SMP related SBI calls to SBI_v01")
> >
> > Regards,
> > Bin
>
>
>
> --
> Regards,
> Atish