Hunyue Yau
Low power Linux
HY Research

Hunyue Yau is a consultant with HY Research with experience on ARM-based mobile embedded Linux systems such as the TI OMAP2/3 platforms. His prior work includes more than 10 years of testing, development, and deployment of voice and networking equipment using ARM, PPC, and x86 architectures.

Hunyue has designed and implemented several Linux-based appliances, including one of the first embedded Linux appliances, a custom db box back in 1996. Users of the Linux-based appliances include a city government and a major wireless carrier. He has been working with Linux since 1993, starting with a system based on SLS, a precursor of Slackware. Formal education include a BS EE from the California Institute of Technology.


As Linux utilization in the mobile arena increases, low power Linux becomes essential. Of the multitude of architectures that Linux runs on, this talk will focus on x86 and ARM. Coverage will range from fully embedded devices like phones, to hybrid embedded devices like PDAs and Mobile Internet Devices (MID) to mobile desktop style devices like laptops will be addressed.

Topics covered will be:

- Benefits . Greener product . Smaller form factor . Less thermal issues

- General: Power management in the kernel - APM - ACPI - Disabling unused parts of the system - Clock speed/voltage management

- Sleeping when idle - Trade offs: Latency vs power usage

- Examples of low power focused x86 implementations: Atom

- Examples of low power focused ARM implementations: OMAP2/OMAP3

- Power consumption of a system vs power consumption of the processor

- Other power reduction techniques from userland

- Hardware power management assistance

Chip level features like wake up support and auto clock shutoff

Automatic shut off of transceivers

Dedicated blocks and/or chips in place of software


Hardware component choices

- Current state of things/examples:

Atom "netbooks"

OMAP2 devices like the N800

OMAP3 devices like the BeagleBoard