Re: [v4 PATCH 1/3] RISC-V: Define fixmap bindings for generic early ioremap support

[Atish Patra]

On Tue, Apr 21, 2020 at 12:52 PM Palmer Dabbelt <palmer@xxxxxxxxxxx> wrote:
>
> I missed that there's a v4 now, so I'm jumping over here
>

Thanks. Just FYI: Ard has already pulled the patches 1 & 2 into efi-next.
So the v4 will only have 3 patches, mostly riscv specific stuff.

> On Mon, 20 Apr 2020 20:33:34 PDT (-0700), Atish Patra wrote:
> > UEFI uses early IO or memory mappings for runtime services before
> > normal ioremap() is usable. This patch only adds minimum necessary
> > fixmap bindings and headers for generic ioremap support to work.
> >
> > Signed-off-by: Atish Patra <atish.patra@xxxxxxx>
> > Acked-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
> > ---
> >  arch/riscv/Kconfig              |  1 +
> >  arch/riscv/include/asm/Kbuild   |  1 +
> >  arch/riscv/include/asm/fixmap.h | 18 ++++++++++++++++++
> >  arch/riscv/include/asm/io.h     |  1 +
> >  4 files changed, 21 insertions(+)
> >
> > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> > index a197258595ef..f39e326a7a42 100644
> > --- a/arch/riscv/Kconfig
> > +++ b/arch/riscv/Kconfig
> > @@ -68,6 +68,7 @@ config RISCV
> >       select ARCH_HAS_GCOV_PROFILE_ALL
> >       select HAVE_COPY_THREAD_TLS
> >       select HAVE_ARCH_KASAN if MMU && 64BIT
> > +     select GENERIC_EARLY_IOREMAP
> >
> >  config ARCH_MMAP_RND_BITS_MIN
> >       default 18 if 64BIT
> > diff --git a/arch/riscv/include/asm/Kbuild b/arch/riscv/include/asm/Kbuild
> > index 3d9410bb4de0..59dd7be55005 100644
> > --- a/arch/riscv/include/asm/Kbuild
> > +++ b/arch/riscv/include/asm/Kbuild
> > @@ -1,4 +1,5 @@
> >  # SPDX-License-Identifier: GPL-2.0
> > +generic-y += early_ioremap.h
> >  generic-y += extable.h
> >  generic-y += flat.h
> >  generic-y += kvm_para.h
> > diff --git a/arch/riscv/include/asm/fixmap.h b/arch/riscv/include/asm/fixmap.h
> > index 2368d49eb4ef..ba5096d65fb0 100644
> > --- a/arch/riscv/include/asm/fixmap.h
> > +++ b/arch/riscv/include/asm/fixmap.h
> > @@ -30,6 +30,24 @@ enum fixed_addresses {
> >       FIX_TEXT_POKE1,
> >       FIX_TEXT_POKE0,
> >       FIX_EARLYCON_MEM_BASE,
> > +     /*
> > +      * Make sure that it is 2MB aligned.
> > +      */
> > +#define NR_FIX_SZ_2M (SZ_2M / PAGE_SIZE)
> > +     FIX_THOLE = NR_FIX_SZ_2M - FIX_PMD - 1,
> > +
> > +     __end_of_permanent_fixed_addresses,
> > +     /*
> > +      * Temporary boot-time mappings, used by early_ioremap(),
> > +      * before ioremap() is functional.
> > +      */
> > +#define NR_FIX_BTMAPS                (SZ_256K / PAGE_SIZE)
> > +#define FIX_BTMAPS_SLOTS     7
> > +#define TOTAL_FIX_BTMAPS     (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)
> > +
> > +     FIX_BTMAP_END = __end_of_permanent_fixed_addresses,
> > +     FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1,
> > +
> >       __end_of_fixed_addresses
> >  };
> >
> > diff --git a/arch/riscv/include/asm/io.h b/arch/riscv/include/asm/io.h
> > index 0f477206a4ed..047f414b6948 100644
> > --- a/arch/riscv/include/asm/io.h
> > +++ b/arch/riscv/include/asm/io.h
> > @@ -14,6 +14,7 @@
> >  #include <linux/types.h>
> >  #include <asm/mmiowb.h>
> >  #include <asm/pgtable.h>
> > +#include <asm/early_ioremap.h>
> >
> >  /*
> >   * MMIO access functions are separated out to break dependency cycles
>
> Just so it doesn't get lost (the patch is the same)
>
> Reviewed-by: Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx>



-- 
Regards,
Atish