[PULL][Trusty] arm64: Add EFI stub support

[Dann Frazier]

On Thu, Apr 23, 2015 at 3:27 AM, Luis Henriques
<luis.henriques at canonical.com> wrote:
> On Fri, Apr 10, 2015 at 03:11:49PM -0600, Dann Frazier wrote:
>> Ubuntu currently provides arm64-efi cloud images, but the 14.04 LTS
>> images aren't actually bootable due to the lack of EFI stub support.
>> This means there is currently no Ubuntu LTS option for users deploying
>> guests on ARM64-based clouds, and that's just not cool, man.
>>
>>   git://kernel.ubuntu.com/dannf/trusty-xgene.git@arm64-efi
>>
>
> I believe that "@arm64-efi" means the arm64-efi branch (and that the
> arm64 EFI are the 21 patches on top of ca13cad7da7c).

Yes - I failed to remember Tim's advice on sending a proper pull
request. I'll prepare a branch that addresses your comments below (but
makes no and use git-request-pull to resubmit.

>> Prebuilt packages are available in ppa:dannf/arm64efi.
>>
>> This is based on an earlier backport from Ming Lei, but modified to
>> minimize the changes (read: regression risk) to x86. There are no
>> changes under arch/x86, and all of the arch-indep changes are adding
>> new interfaces that x86 doesn't use.
>>
>> With these changes, the trusty cloud images are now bootable. However,
>> they do not have automatic console detection (you have to manually add
>> console=ttyAMA0), and do not yet have an EFI RTC driver - that work is
>> up next.
>>
>> I've regression tested on X-Gene/u-boot and on the QEMU arm64 virt
>> model booted w/ -kernel to make sure it doesn't break non-EFI systems.
>> Thanks to Rod Smith for regression testing on an EFI-mode mac and
>> within virtualbox to confirm I didn't break EFI mode on x86.
>>
>> --
>> kernel-team mailing list
>> kernel-team at lists.ubuntu.com
>> https://lists.ubuntu.com/mailman/listinfo/kernel-team
>
> I've just started looking at this patchset and I have a few questions.
> The 1st one is related with the new configuration options
> (CONFIG_EFI_PARAMS_FROM_FDT, CONFIG_GENERIC_EARLY_IOREMAP and
> CONFIG_LIBFDT).  I suspect you would want these to be set to 'y' for
> arm64; but what about other arches?  Should they be set to 'n'?

updateconfigs will enable them in config.common, but they only get
enabled in the config generated for arm64.

> Anyway, maybe you could include an extra "UBUNTU: [Config]" patch in
> this patchset?

Will do.

> Also, I'm curious about the "cherry picked from..." line, instead of the
> more standard "cherry picked from commit...".  You should use '-x'
> when doing the cherry-pick.  Also, some of these commits should
> actually be replaced by a "backported from commit..." as they are not
> clean cherry-picks but backports instead (e.g. the backport of
> 3c7f255039a2 "arm64: efi: add EFI stub").

Ah, I didn't know about -x! My new branch will use -x where
appropriate, and using "backported from" instead of "cherry picked
from" in other cases. Thanks Luís!

 -dann

> Cheers,
> --
> Luís