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

[Emmanuel Vadot]

On Tue, 20 Jun 2017 14:08:08 +0200
Alexander Graf <agraf at suse.de> wrote:

> 
> 
> 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

 I'll add GPT too, do we support/care about other schemes ?

-- 
Emmanuel Vadot <manu at bidouilliste.com> <manu at freebsd.org>