Re: Building 32-bit xen.efi for 32-bit EFI platforms

[David Vrabel <david.vrabel@citrix.com>]

On 24/11/14 14:59, Zhuan Chen wrote:
> Hi,
> 
> I am wondering whether it's possible to build 32-bit xen.efi for the
> 32-bit EFI platform? One way of building xen.efi I learnt is to make
> the binutils configured with the x86_64-pep emulation (according to
> the document http://xenbits.xenproject.org/docs/unstable/misc/efi.html).
> The resulted xen.efi is 64-bit mode. Is it possible to build xen.efi
> as the 32-bit mode?
> 
> The reason for this question is due to my effort of installing Xen on
> the Asus Transformer Book T100, which is one of the Bay Trail Atom
> (64-bit processors) tablets shipped with 32-bit EFI firmware. This
> requires the support of the 32-bit EFI bootloader. Such platforms seem
> to become common and Linux kernel from 3.15 also provides the EFI
> mixed mode to support 64-bit kernels running from 32-bit EFI firmware.

You may want to look at using another bootloader (such as grub 2) to
chainload Xen.

Daniel Kiper has the necessary patches to Xen to make this work
(although I've only tried it with 64-bit grub 2).

David