LinuxCon + CloudOpen + ELC-E Europe 2014

ACPI was introduced when hardware compatibility with the IBM PC became insufficient to maintain the PC ecosystem. It allowed a single binary OS image to run on various platforms using the same CPU architecture, but not exactly hardware-compatible with one another. Today, Device Trees are used to address the same platform fragmentation problem in the ARM ecosystem. Of course, there are differences between ACPI and DT. Unlike DT, ACPI had a difficulty with passing arbitrary data to the OS, but that limitation is now being removed. With ACPI now able to provide the same data as DT, a need has arisen for a shared firmware-interface-agnostic specification of hardware properties. Similarly, the platform firmware interface access for device drivers in the OS should be unified, so the same driver can work equally well on systems with ACPI or DT. I will discuss work toward that goal in Linux.