[PATCH] doc: update bootefi man-page

[Kyle Evans]

On Mon, Apr 11, 2022 at 2:11 PM Heinrich Schuchardt
<heinrich.schuchardt at canonical.com> wrote:
>
> A image_size parameter has been added to the bootefi parameter.
> Describe all parameters.
>
> Correct how the description of how the device-path in the loaded
> image protocol is determined.
>
> Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt at canonical.com>
> ---
>  doc/usage/cmd/bootefi.rst | 19 ++++++++++++++++---
>  1 file changed, 16 insertions(+), 3 deletions(-)
>
> diff --git a/doc/usage/cmd/bootefi.rst b/doc/usage/cmd/bootefi.rst
> index 31279fc0cb..bb354b2255 100644
> --- a/doc/usage/cmd/bootefi.rst
> +++ b/doc/usage/cmd/bootefi.rst
> @@ -9,7 +9,7 @@ Synopsis
>
>  ::
>
> -    bootefi [image_addr] [fdt_addr]
> +    bootefi [image_addr] [fdt_addr [image_size]]
>      bootefi bootmgr [fdt_addr]
>      bootefi hello [fdt_addr]
>      bootefi selftest [fdt_addr]
> @@ -41,13 +41,26 @@ command sequence to run a UEFI application might look like
>      load mmc 0:1 $kernel_addr_r /EFI/grub/grubaa64.efi
>      bootefi $kernel_addr_r $fdt_addr_r
>
> -The last file loaded defines the image file path in the loaded image protocol.
> -Hence the executable should always be loaded last.
> +The last UEFI binary loaded defines the image file path in the loaded image
> +protocol.
>

You might also add:

If image_addr does not match the last UEFI binary loaded, then a memory mapped
device path will be used for the loaded image protocol.

It's maybe implied by the address not matching, but I tend to think
it's worth explicitly noting that thought has been put into this.

>  The value of the environment variable *bootargs* is converted from UTF-8 to
>  UTF-16 and passed as load options in the loaded image protocol to the UEFI
>  binary.
>
> +image_addr
> +    Address of the UEFI binary.
> +
> +fdt_addr
> +    Address of the device-tree or '-'. If no address is specifiy, the
> +    environment variable $fdt_addr is used as first fallback, the address of
> +    U-Boot's internal device-tree $fdtcontroladdr as second fallback.
> +    When using ACPI no device-tree shall be specified.
> +

s/specifiy/specified/

> +image_size
> +    Size of the UEFI binary file. This argument is only needed if *image_addr*
> +    does not match the address of the last loaded UEFI binary.
> +
>  Note
>      UEFI binaries that are contained in FIT images are launched via the
>      *bootm* command.
> --