[PATCH 1/1] riscv: clarify meaning of CONFIG_SBI_V02

[Rick Chen]

Hi Heinrich

> From: Heinrich Schuchardt <heinrich.schuchardt at canonical.com>
> Sent: Tuesday, November 08, 2022 11:14 PM
> To: Bin Meng <bmeng.cn at gmail.com>
> Cc: Rick Jian-Zhi Chen(陳建志) <rick at andestech.com>; Leo Yu-Chi Liang(梁育齊) <ycliang at andestech.com>; Conor Dooley <conor.dooley at microchip.com>; u-boot at lists.denx.de
> Subject: Re: [PATCH 1/1] riscv: clarify meaning of CONFIG_SBI_V02
>
> On 11/8/22 16:05, Bin Meng wrote:
> > Hi Heinrich,
> >
> > On Tue, Nov 8, 2022 at 10:53 PM Heinrich Schuchardt
> > <heinrich.schuchardt at canonical.com> wrote:
> >>
> >> Describe that CONFIG_SBI_V02=y does not mean SBI specification v0.2
> >> but v0.2 or later.
> >>
> >> Signed-off-by: Heinrich Schuchardt
> >> <heinrich.schuchardt at canonical.com>
> >> ---
> >>   arch/riscv/Kconfig | 14 +++++++-------
> >>   1 file changed, 7 insertions(+), 7 deletions(-)
> >>
> >> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index
> >> 4d64e9be3f..ebc4bef220 100644
> >> --- a/arch/riscv/Kconfig
> >> +++ b/arch/riscv/Kconfig
> >> @@ -257,16 +257,16 @@ config SBI_V01
> >>            deprecated in future once legacy M-mode software are no longer in use.
> >>
> >>   config SBI_V02
> >> -       bool "SBI v0.2 support"
> >> +       bool "SBI v0.2 or later support"
> >>          depends on SBI
> >>          help
> >> -         This config allows kernel to use SBI v0.2 APIs. SBI v0.2 is more
> >> -         scalable and extendable to handle future needs for RISC-V supervisor
> >> -         interfaces. For example, with SBI v0.2 HSM extension, only a single
> >> -         hart need to boot and enter operating system. The booting hart can
> >> -         bring up secondary harts one by one afterwards.
> >> +         The SBI specification introduced the concept of extensions in version
> >> +         v0.2. With this configuration option U-Boot can detect and use SBI
> >> +         extensions. With the HSM extension introduced in SBI 0.2, only a
> >> +         single hart needs to boot and enter the operating system. The booting
> >> +         hart can bring up secondary harts one by one afterwards.
> >>
> >> -         Choose this option if OpenSBI v0.7 or above release is used together
> >> +         Choose this option if OpenSBI release v0.7 or above is used
> >> + together
> >>            with U-Boot.
> >>
> >>   endchoice
> >
> > I remember this option was borrowed from the Linux kernel. Do you plan
> > to send patch to Linux kernel too?
>
> Linux uses a single configuration symbol
> CONFIG_RISCV_SBI_V01 "SBI v0.1 support"
>
> So there is no need for a change there.
>
> SBI v0.1 is really obsolete. Can we drop support for it in U-Boot?

I  am fine to remove it.

Thanks,
Rick