The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 17, 2009
Filed:
Mar. 27, 2002
Rodney W. Schmidt, Dripping Springs, TX (US);
Brian C. Barnes, Round Rock, TX (US);
Geoffrey S. Strongin, Austin, TX (US);
Rodney W. Schmidt, Dripping Springs, TX (US);
Brian C. Barnes, Round Rock, TX (US);
Geoffrey S. Strongin, Austin, TX (US);
Advanced Micro Devices, Inc., Austin, TX (US);
Abstract
A method and apparatus for selectively executing an I/O instruction. The method includes creating an I/O permission bitmap in a memory and receiving an I/O port number and a security context identification (SCID) value. The method also includes using the SCID value and the I/O port number to access the I/O permission bitmap stored to obtain a permission bit corresponding to the I/O port and executing the I/O instruction dependent upon a value of the permission bit corresponding to the I/O port. The I/O permission bitmap includes a plurality of permission bits. Each of the permission bits corresponds to a different one of a plurality of I/O ports. Each of the permission bits has a value indicating whether access to the corresponding I/O port is allowed. The I/O port number indicates the I/O port referenced by the I/O instruction. The SCID value indicates a security context level of a memory location including the I/O instruction.