[RFC PATCH 3/3] riscv: Add riscv.fwsz kernel parameter

[Guo Ren]

On Tue, Nov 23, 2021 at 10:34 AM Randy Dunlap <rdunlap at infradead.org> wrote:
>
> On 11/22/21 5:57 PM, guoren at kernel.org wrote:
> > From: Guo Ren <guoren at linux.alibaba.com>
> >
> > The firmware of riscv (such as opensbi) occupy 2MB(64bit) /
> > 4MB(32bit) in Linux. It's very wasteful to small memory footprint
> > soc chip such as Allwinner D1s/F133. The kernel parameter gives a
> > chance to users to set the proper size of the firmware and get
> > more than 1.5MB of memory.
> >
> > Signed-off-by: Guo Ren <guoren at linux.alibaba.com>
> > Cc: Palmer Dabbelt <palmer at dabbelt.com>
> > Cc: Anup Patel <anup.patel at wdc.com>
> > Cc: Atish Patra <atishp at rivosinc.com>
> > ---
> >   Documentation/admin-guide/kernel-parameters.txt | 3 +++
> >   1 file changed, 3 insertions(+)
> >
> > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
> > index 9725c546a0d4..ee505743c8f4 100644
> > --- a/Documentation/admin-guide/kernel-parameters.txt
> > +++ b/Documentation/admin-guide/kernel-parameters.txt
> > @@ -4964,6 +4964,9 @@
> >                       [KNL] Disable ring 3 MONITOR/MWAIT feature on supported
> >                       CPUs.
> >
> > +     riscv.fwsz=nn[KMG]
> > +                     [RISC-V] Determine firmware size to save memory
>
> Is "Determine" like "Set"?  The user is setting (telling the software)
> the firmware size?
I mean "Set" here, thx for pointing it out.

>
> "Determine" makes it sound to me like the Linux software is somehow
> helping to determine the firmware size.
>
> > +
> >       ro              [KNL] Mount root device read-only on boot
> >
> >       rodata=         [KNL]
> >
>
>
> --
> ~Randy



-- 
Best Regards
 Guo Ren

ML: https://lore.kernel.org/linux-csky/