[U-Boot] [PATCH v2] efi: Export mbr partition for EFI.

[Alexander Graf]

On 20.06.17 14:02, Ard Biesheuvel wrote:
> On 20 June 2017 at 13:55, Alexander Graf <agraf at suse.de> wrote:
>>
>>
>> On 20.06.17 08:35, Emmanuel Vadot wrote:
>>>
>>> While MBR partition isn't supposed to work in a EFI environment some
>>
>>
>> It actually is supposed to work :). I've used it on edk2 based systems a few
>> times already.
>>
> 
> Correct. Even though UEFI reinvented everything including
> partitioning, the spec mandates support for MBR, GPT and El Torito for
> platforms that have the ability to boot from SSD/HDD drives and/or
> optical drives.
> 
>>> board rely partially or fully on MBR (BeagleBone, RPI and probably
>>> others).
>>> This export the MBR partition as logical partition which is useful to efi
>>> application that cannot read raw disks.
>>>
>>> Signed-off-by: Emmanuel Vadot <manu at bidouilliste.com>
>>
>>
>> I think we should do whatever edk2 does here to stay compatible. Ard, can
>> you please enlighten me what that would be? Does edk2 expose logical
>> partitions as raw disks?
>>
> 
> The UEFI partition driver consumes block and disk I/O protocols of raw
> devices and produces the same protocols for each individual partition
> that it recognizes.
> 
> I hope this answers your question, otherwise could you elaborate?

This basically answers my question, yes.

So we really should just provide block devices for *every* partition 
type we support, not just MBR as is done in this patch.

Emmanuel, could you please extend the patch to cover all partition label 
types?


Thanks,

Alex