Re: [PATCH v5 7/7] RISC-V: Add EFI stub support.

[Ard Biesheuvel <ardb@kernel.org>]

On Thu, 23 Apr 2020 at 13:15, Ard Biesheuvel <ardb@kernel.org> wrote:
>
> On Wed, 22 Apr 2020 at 20:48, Atish Patra <Atish.Patra@wdc.com> wrote:
> >
> > On Wed, 2020-04-22 at 19:24 +0200, Ard Biesheuvel wrote:
> > > From: Atish Patra <atish.patra@wdc.com>
> > >
> > > Add a RISC-V architecture specific stub code that actually copies the
> > > actual kernel image to a valid address and jump to it after boot
> > > services
> > > are terminated. Enable UEFI related kernel configs as well for RISC-
> > > V.
> > >
> > > Signed-off-by: Atish Patra <atish.patra@wdc.com>
> > > Link:
> > > https://lore.kernel.org/r/20200421033336.9663-4-atish.patra@wdc.com
> > > [ardb: - move hartid fetch into check_platform_features()
> > >        - use image_size not reserve_size
> > >        - moved asm/efi.h addition into separate patch ]
> > > Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> > > ---
> > >  arch/riscv/Kconfig                        |  20 ++++
> > >  arch/riscv/Makefile                       |   1 +
> > >  arch/riscv/configs/defconfig              |   1 +
> > >  drivers/firmware/efi/Kconfig              |   4 +-
> > >  drivers/firmware/efi/libstub/Makefile     |  10 ++
> > >  drivers/firmware/efi/libstub/riscv-stub.c | 109 ++++++++++++++++++++
> > >  6 files changed, 143 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> > > index f05dd09acd48..54c78cafcd35 100644
> > > --- a/arch/riscv/Kconfig
> > > +++ b/arch/riscv/Kconfig
> > > @@ -379,10 +379,30 @@ config CMDLINE_FORCE
> > >
> > >  endchoice
> > >
> > > +config EFI_STUB
> > > +     bool
> > > +
> > > +config EFI
> > > +     bool "UEFI runtime support"
> > > +     depends on OF
> > > +     select LIBFDT
> > > +     select UCS2_STRING
> > > +     select EFI_PARAMS_FROM_FDT
> > > +     select EFI_STUB
> > > +     select EFI_GENERIC_STUB
> >
> > As palmer suggested RISCV_ISA_C should be selected here to avoid
> > unintentional errors. Otherwise, every looks good.
> >
>
> Ah, I must have misunderstood. I thought using c.li instead of li was
> sufficient here.
>
>
> In any case, once Palmer confirms that he is ok with the approach I
> suggested, he can fix that up when applying the patches.
>

Actually, I can do slightly better, and put the asm/efi.h patch back
into this one.

I'll do a respin once we've agreed that this is the approach we are taking.