[U-Boot] [PATCH v3 15/21] efi_loader: add bootmgr

[Rob Clark]

On Thu, Sep 21, 2017 at 12:58 AM, Simon Glass <sjg at chromium.org> wrote:
> Hi,
>
> On 20 September 2017 at 08:09, Rob Clark <robdclark at gmail.com> wrote:
>> On Wed, Sep 20, 2017 at 5:08 AM, Alexander Graf <agraf at suse.de> wrote:
>>>
>>>
>>> On 14.09.17 00:05, Rob Clark wrote:
>>>>
>>>> Similar to a "real" UEFI implementation, the bootmgr looks at the
>>>> BootOrder and BootXXXX variables to try to find an EFI payload to load
>>>> and boot.  This is added as a sub-command of bootefi.
>>>>
>>>> The idea is that the distro bootcmd would first try loading a payload
>>>> via the bootmgr, and then if that fails (ie. first boot or corrupted
>>>> EFI variables) it would fallback to loading bootaa64.efi.  (Which
>>>> would then load fallback.efi which would look for \EFI\*\boot.csv and
>>>> populate BootOrder and BootXXXX based on what it found.)
>>>>
>>>> Signed-off-by: Rob Clark <robdclark at gmail.com>
>>>
>>>
>>> Would it make sense to convert the bootmgr into a genuine EFI application
>>> now that we have Heinrich's test framework available?
>>>
>>
>> I had considered that, but then decided it was nice to be able to use
>> printf()/malloc()/etc.. plus easier to gdb/debug..
>>
>> Maybe at some point it would be worth trying to fixup edk2 build so
>> some things like this and HII/unicode protocols and maybe a few other
>> things could be built as standalone .efi drivers and loaded by u-boot.
>> (Might make sense by the time someone wants a full blown HII "bios
>> setup menu" ;-))
>
> Another advantage of the current approach used by this series is that
> we can test it with sandbox. With a separate EFI application we would
> lose that ability.
>

jfwiw, I do actually have Shell.efi very nearly loading in sandbox..
it crashes part-way through startup (shortly after reading "ShellOpt"
variable) and I haven't had a chance to debug further.. but I suspect
in some form or another having VA != "PA" in sandbox is biting us.

Anyways, getting a bit off topic, but separate .efi in sandbox doesn't
seem like it should be completely out of the question for sandbox..
and it would make sandbox *way* more useful for EFI testing, since
this is really half of the point of efi..

BR,
-R