[U-Boot] [PATCH v2 20/63] x86: Kconfig: Add location options for 16/32-bit init

[Bin Meng]

Hi Simon,

On Sun, Nov 20, 2016 at 4:25 AM, Simon Glass <sjg at chromium.org> wrote:
> At present all 16/32-bit init is controlled by CONFIG_X86_RESET_VECTOR. If
> this is enabled, then U-Boot is the 'first' boot loader and handles execution
> from the reset vector through to U-Boot's command prompt. If it is not
> enabled then U-Boot starts at the 32-bit entry and skips most of its init,
> assuming that the previous boot loader has done this already.
>
> With the move to suport 64-bit operation, we have more cases to consider.
> The 16-bit and 32-bit init may be in SPL rather than in U-Boot proper.
>
> Add Kconfig options which control the location of the 16-bit and the 32-bit
> init. These are not intended to be user-setting except for experimentation.
> Their values should be determined by whether 64-bit U-Boot is used.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
> Changes in v2: None
>
>  arch/x86/Kconfig | 39 +++++++++++++++++++++++++++++++++++++++
>  1 file changed, 39 insertions(+)
>
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 5db8f13..e57362e 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -135,6 +135,45 @@ config X86_RESET_VECTOR
>         bool
>         default n
>
> +# The following options control where the 16-bit and 32-bit init lies
> +# If SPL is enabled then it normally holds this init code, and U-Boot proper
> +# is normally a 64-bit build.
> +#
> +# The 16-bit init refers to the reset vector and the small amount of code to
> +# get the processor into 32-bit mode. It may be in SPL or in U-Boot proper,
> +# or missing altogether if U-Boot is started from EFI or coreboot.
> +#
> +# The 32-bit init refers to processor init, running binary blobs including
> +# FSP, setting up interrupts and anything else that needs to be done in
> +# 32-bit code. It is normally in the same place as 32-bit init.

in the same place as "16-bit" init?

> +config X86_16BIT_INIT
> +       bool
> +       depends on X86_RESET_VECTOR
> +       default y if X86_RESET_VECTOR && !SPL
> +       help
> +         This is enabled when 16-bit init is in U-Boot proper
> +
> +config SPL_X86_16BIT_INIT
> +       bool
> +       depends on X86_RESET_VECTOR
> +       default y if X86_RESET_VECTOR && SPL
> +       help
> +         This is enabled when 16-bit init is in SPL
> +
> +config X86_32BIT_INIT
> +       bool
> +       depends on X86_RESET_VECTOR
> +       default y if X86_RESET_VECTOR && !SPL
> +       help
> +         This is enabled when 32-bit init is in U-Boot proper
> +
> +config SPL_X86_32BIT_INIT
> +       bool
> +       depends on X86_RESET_VECTOR
> +       default y if X86_RESET_VECTOR && SPL
> +       help
> +         This is enabled when 32-bit init is in SPL
> +
>  config RESET_SEG_START
>         hex
>         depends on X86_RESET_VECTOR
> --

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

Regards,
Bin