A standards organization has created a boot environment for tablets and PCs that could potentially run a 64-bit version of Windows RT.
The Unified Extensible Firmware Interface (UEFI) Forum announced that its boot firmware specifications will now support ARMv8, a 64-bit processor architecture announced by ARM in 2011. ARM's processors are used in most smartphones and tablets, and chip makers such as Nvidia and Samsung are expected to release 64-bit processors for smartphones and tablets in the future.
Microsoft on Windows 8 and RT requires PCs and tablets to carry a feature called Secure Boot, which prevents a system from being hijacked. The Secure Boot environment is based on UEFI firmware and ARM has already said it is working with Microsoft to develop a 64-bit version of Windows for ARM-based devices. However, it is not yet clear when the OS will come out.
ARM expects 64-bit processors to start shipping later this year or early next year. Most smartphones and tablets today use 32-bit ARM processors.
The UEFI support for ARM 64-bit could be one more step to bringing Windows RT to 64-bit, though the benefits could be invisible to end users, said Dean McCarron, principal analyst at Mercury Research.
"We can have a standardized firmware interface that can be used across PCs and other devices rather than having legacy BIOS," McCarron said.
UEFI has been widely adopted on PCs, so there could be a higher uptake by device makers making x86-compatible Windows tablets, McCarron said.
Only a handful of Windows RT tablets are available, although Acer is expected to release a tablet with the next version of the OS, due out in the second half of this year.
The UEFI specification supports a wide number of OSes and is used on Apple Macs. A large number of Android smartphones and tablets use customized bootloaders based on the kernels and specifications of devices. UEFI is desirable as it may bring some flexibility in mobile-device configurations, McCarron said.