Flash memory protection scheme for secured shared BIOS implementation in personal computers with an embedded controller

A method for protecting contents of a shared memory in a memory device controlled by an embedded controller, by allowing dynamic setting of access permissions to said contents, and by allowing updating and recovery of said contents, said method comprising the steps of:

• coupling to said memory device a computerized system that comprises at least one Host that is coupled to said memory device;
• providing access paths to said shared memory, to said at least one Host, and to said embedded controller;
• coupling to said memory device an arbitration device for allocating the access paths to said memory device and for permitting access to at least one portion of the memory device, wherein the memory device is partitioned into separate portions that are designated for storing different types of data, and a location in the memory device is designated for storing protection information that includes data related to access operations allowed by at least one access path to a part of the shared memory;
• coupling to said memory device and to said arbitration device an access control unit that enable/disables access to predetermined portions of said shared memory;
• and
• coupling to said arbitration device a protection mechanism that directs said arbitration unit as to the access privileges of a plurality of different access paths.