[U-Boot] [PATCH v2 39/47] x86: Add support for passing tables into U-Boot

[Bin Meng]

On Fri, Jul 31, 2015 at 11:31 PM, Simon Glass <sjg at chromium.org> wrote:
> The EFI stub provides information to U-Boot in a table. This includes the
> memory map which is needed to decide where to relocate U-Boot. Collect this
> information in the early init code and store it in global_data.
>
> Fix up the BIST code at the same time since we don't have it when booting
> from EFI and can assume it is 0.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
> Changes in v2:
> - Zero BIST when starting from EFI/coreboot
>
>  arch/x86/cpu/start.S               | 19 ++++++++++++++++++-
>  arch/x86/include/asm/global_data.h |  1 +
>  arch/x86/lib/asm-offsets.c         |  1 +
>  3 files changed, 20 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/cpu/start.S b/arch/x86/cpu/start.S
> index 9b2584d..fdef2bb 100644
> --- a/arch/x86/cpu/start.S
> +++ b/arch/x86/cpu/start.S
> @@ -42,6 +42,13 @@ _x86boot_start:
>
>         /* Tell 32-bit code it is being entered from an in-RAM copy */
>         movl    $GD_FLG_WARM_BOOT, %ebx
> +
> +       /*
> +        * Zero the BIST (Built-In Self Test) value since we don't have it.
> +        * It must be 0 or the previous loader would have reported an error.
> +        */
> +       movl    $0, %ebp
> +
>         jmp     1f
>
>         /* Add a way for tools to discover the _start entry point */
> @@ -53,9 +60,13 @@ _start:
>          * Set %bx to 0 to indicate this.
>          */
>         movl    $GD_FLG_COLD_BOOT, %ebx
> -1:
> +
>         /* Save BIST */
>         movl    %eax, %ebp
> +1:
> +
> +       /* Save table pointer */
> +       movl    %ecx, %esi
>
>         /* Load the segement registers to match the GDT loaded in start16.S */
>         movl    $(X86_GDT_ENTRY_32BIT_DS * X86_GDT_ENTRY_SIZE), %eax
> @@ -133,7 +144,13 @@ car_init_ret:
>         movl    %esi, (%edx)
>
>  skip_hob:
> +#else
> +       /* Store table pointer */
> +       movl    %esp, %edx
> +       addl    $GD_TABLE, %edx
> +       movl    %esi, (%edx)
>  #endif
> +
>         /* Setup first parameter to setup_gdt, pointer to global_data */
>         movl    %esp, %eax
>
> diff --git a/arch/x86/include/asm/global_data.h b/arch/x86/include/asm/global_data.h
> index 80ebe3e..f7e3889 100644
> --- a/arch/x86/include/asm/global_data.h
> +++ b/arch/x86/include/asm/global_data.h
> @@ -69,6 +69,7 @@ struct arch_global_data {
>         char *mrc_output;
>         unsigned int mrc_output_len;
>         void *gdt;                      /* Global descriptor table */
> +       ulong table;                    /* Table pointer from previous loader */
>  };
>
>  #endif
> diff --git a/arch/x86/lib/asm-offsets.c b/arch/x86/lib/asm-offsets.c
> index 70ccf1b..9da04dd 100644
> --- a/arch/x86/lib/asm-offsets.c
> +++ b/arch/x86/lib/asm-offsets.c
> @@ -21,5 +21,6 @@ int main(void)
>  #ifdef CONFIG_HAVE_FSP
>         DEFINE(GD_HOB_LIST, offsetof(gd_t, arch.hob_list));
>  #endif
> +       DEFINE(GD_TABLE, offsetof(gd_t, arch.table));
>         return 0;
>  }
> --

Reviewed-by: Bin Meng <bmeng.cn at gmail.com>