Device Property Names

Strictly speaking, DDI/DKI software property names are not restricted in any way; however, there are certain recommended uses. As defined in IEEE 1275-1994 (the Standard for Boot Firmware), a property “is a human readable text string consisting of one to thirty-one printable characters. Property names shall not contain upper case characters or the characters "/", "\", ":", "[", "]" and "@". Property names beginning with the character "+" are reserved for use by future revisions of IEEE 1275-1994.” By convention, underscores are not used in property names; use a hyphen (-) instead. Also by convention, property names ending with the question mark character (auto-boot?) contain values that are strings, typically TRUE or FALSE.

Predefined property names are listed in publications of the IEEE 1275 Working Group. See http://playground.sun.com/1275 for information on how to obtain these publications. For a discussion of adding properties in driver configuration files, see driver.conf(4). The pm(9P) and pm-components(9P) man pages shows how properties are used in power management. Read the sd(7D) man page as an example of how properties should be documented in device driver man pages.