UEFI: arndale does not boot with initrd

Booting the Arndale board with UEFI and an initrd fails.

I think the initrd and FDT files need to be at the start of a 1MB boundary, and that's how u-boot loads them too.

I see a log like this before the board hangs after uncompressing the kernel with no more output:

[1] Linaro SD card
 - VenHw(3A02E7FE-0649-4FB4-BE4F-A862CA1872A9)/HD(2,MBR,0x000EDCA3,0x2000,0x1A000)/uImage
 - Initrd: VenHw(3A02E7FE-0649-4FB4-BE4F-A862CA1872A9)/HD(2,MBR,0x000EDCA3,0x2000,0x1A000)/uInitrd
 - Arguments: root=/dev/mmcblk1p1 rw rootwait console=ttySAC2,115200n8 init --no-log
 - FDT: VenHw(3A02E7FE-0649-4FB4-BE4F-A862CA1872A9)/HD(2,MBR,0x000EDCA3,0x2000,0x1A000)/board.dtb
 - LoaderType: Linux kernel with Local FDT
-----------------------
Global FDT Config
 - VenHw(3A02E7FE-0649-4FB4-BE4F-A862CA1872A9)/HD(2,MBR,0x000A65DC,0x59B303,0x3B7C)/exynos5250-arndale.dtb
-----------------------
[a] Boot Manager
[b] Shell
Start: 1
Warning: Failed to load FDT below address 0x50004000 (Out of Resources). Will try again at a random address anywhere.
WARNING: Loaded FDT at random address 0x9EA59000.
WARNING: There is a risk of accidental overwriting by other code/data.
BootArg: root=/dev/ram0 rw ramdisk=8192 initrd=0x41000000,8M console=ttySAC2,115200 init=/linuxrc
   PEI 0 ms
   DXE 18446744072200 ms
   BDS 18446739780553 ms
   BDS 18446744067076 ms
Total Time = 18446739772411 ms

Starting the kernel:

Uncompressing Linux... done, booting the kernel.