SYSTEM AND METHOD USING VENDOR-LONG DESCRIPTOR IN ACPI FOR CECCSR

摘要

PROBLEM TO BE SOLVED: To manage a system device by using a memory mapped I/O (MMIO). SOLUTION: A local bus adaptor in an ACPI name space uses the MMIO to discriminate a memory address of its child device. An unused construct of the ACPI is used to pass MMIO information to a device driver through an operating system (OS), thus permitting a memory to be reserved with a device and to be kept hidden for the OS. Consequently, a vendor defined resource data type concerning long information such as "vendor-long" is used to pass appropriate information through the OS, and memory information is passed to the OS without a risk that an address is incorrectly assumed to be vacant by the OS which reallocates the address by mistake. COPYRIGHT: (C)2004,JPO