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

[Ilias Apalodimas]

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

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