Re: [PATCH v2] of: of_reserved_mem: clean-up reserved memory with no-map

[DaeRo Lee]

2024년 5월 22일 (수) 오후 11:31, Rob Herring <robh@xxxxxxxxxx>님이 작성:
>
> On Wed, May 01, 2024 at 10:23:59PM +0900, skseofh@xxxxxxxxx wrote:
> > From: Daero Lee <daero_le.lee@xxxxxxxxxxx>
> >
> > In early_init_dt_reserve_memory we only add memory w/o no-map flag to
> > memblock.reserved. But we need to add memory w/ no-map flag to
> > memblock.reserved, because NOMAP and memblock.reserved are semantically
> > different.
> >
> > Signed-off-by: Daero Lee <daero_le.lee@xxxxxxxxxxx>
> > ---
> >  drivers/of/of_reserved_mem.c | 6 +++++-
> >  1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c
> > index 8236ecae2953..d00a17a9cebc 100644
> > --- a/drivers/of/of_reserved_mem.c
> > +++ b/drivers/of/of_reserved_mem.c
> > @@ -81,6 +81,7 @@ static void __init fdt_reserved_mem_save_node(unsigned long node, const char *un
> >  static int __init early_init_dt_reserve_memory(phys_addr_t base,
> >                                              phys_addr_t size, bool nomap)
> >  {
> > +     int err = 0;
> >       if (nomap) {
> >               /*
> >                * If the memory is already reserved (by another region), we
> > @@ -91,7 +92,10 @@ static int __init early_init_dt_reserve_memory(phys_addr_t base,
> >                   memblock_is_region_reserved(base, size))
> >                       return -EBUSY;
> >
> > -             return memblock_mark_nomap(base, size);
> > +
> > +             err = memblock_mark_nomap(base, size);
>
> The last time this was touched, it was to make the handling aligned with
> EFI memory map handling. Is that still going to be the case with this
> change? Or does EFI memory map handling have the same issue?
Can I get more information about EFI memory map handling that you're saying?

1) Are you talking about uefi_mem in the reserved-memory node like below?
 ex) arm64/boot/dts/qcom/qcs404.dtsi
                uefi_mem: memory@9f800000 {
                        reg = <0 0x9f800000 0 0x800000>;
                        no-map;
                };

2) Or, about handling EFI memory map function efi_init() -> reserve_regions()?

>
> > +             if (err)
> > +                     return err;
> >       }
> >       return memblock_reserve(base, size);
> >  }
> > --
> > 2.25.1
> >