On Tue, 2019-06-25 at 09:15 +0000, Ni, Ray wrote:
> But I still need to understand why the *GetBootOption() API is needed.
> Because for quite a long time since the MdeModulePkg/Bds was added, there is no
> such requirement.

It's for CSM, because otherwise all the legacy boot targets other than
IDE are just shown as 'Harddisk'.

See patch [5/7] in this thread which uses the GetBootDescription API
that [4/7] exposes.