[PATCH v2 09/18] armv8: Support not having separate BSS

[Simon Glass]

Hi Ilias,

On Mon, 23 Sept 2024 at 11:49, Ilias Apalodimas
<ilias.apalodimas at linaro.org> wrote:
>
> Hi Simon,
>
> On Fri, 20 Sept 2024 at 10:25, Simon Glass <sjg at chromium.org> wrote:
> >
> > Separate BSS is current mandatory on armv8 but this is not useful for
> > early boot phases. Add support for the combined BSS.
> >
> > Use an #ifdef to avoid using CONFIG_SPL_BSS_START_ADDR which is not
> > valid in this case.
> >
> > Signed-off-by: Simon Glass <sjg at chromium.org>
> > ---
> >
> > (no changes since v1)
> >
> >  arch/arm/cpu/armv8/u-boot-spl.lds | 12 ++++++++++++
> >  1 file changed, 12 insertions(+)
> >
> > diff --git a/arch/arm/cpu/armv8/u-boot-spl.lds b/arch/arm/cpu/armv8/u-boot-spl.lds
> > index 215cedd69a8..fed69644b55 100644
> > --- a/arch/arm/cpu/armv8/u-boot-spl.lds
> > +++ b/arch/arm/cpu/armv8/u-boot-spl.lds
> > @@ -13,8 +13,10 @@
> >
> >  MEMORY { .sram : ORIGIN = IMAGE_TEXT_BASE,
> >                 LENGTH = IMAGE_MAX_SIZE }
> > +#ifdef CONFIG_SPL_SEPARATE_BSS
> >  MEMORY { .sdram : ORIGIN = CONFIG_SPL_BSS_START_ADDR,
> >                 LENGTH = CONFIG_SPL_BSS_MAX_SIZE }
> > +#endif
> >
> >  OUTPUT_FORMAT("elf64-littleaarch64", "elf64-littleaarch64", "elf64-littleaarch64")
> >  OUTPUT_ARCH(aarch64)
> > @@ -56,12 +58,22 @@ SECTIONS
> >         _end = .;
> >         _image_binary_end = .;
> >
> > +#ifdef CONFIG_SPL_SEPARATE_BSS
> >         .bss : {
> >                 __bss_start = .;
> >                 *(.bss*)
> >                 . = ALIGN(8);
> >                 __bss_end = .;
> >         } >.sdram
> > +#else
> > +       .bss (NOLOAD) : {
> > +               __bss_start = .;
> > +               *(.bss*)
> > +                . = ALIGN(8);
> > +               __bss_end = .;
> > +       } >.sram
> > +#endif
>
> This is still going to be separate. The only difference isn't that
> it's not loaded. If you want to combine it with a region, you got to
> do something similar to what we have in armv7, where it overlaps with
> rel.dyn

I don't mind about combining it with a region, But SPL doesn't have
relocation data, right?

My meaning of 'separate' is as described in CONFIG_SPL_SEPARATE_BSS,
i.e. being kept in SDRAM.

>
> Thanks
> /Ilias
> > +       __bss_size = __bss_end - __bss_start;
> >
> >         /DISCARD/ : { *(.rela*) }
> >         /DISCARD/ : { *(.dynsym) }
> > --
> > 2.43.0
> >

Regards,
Simon