Texas Instruments Corporation

Joseph R M Zbiciak

Kai Chirca

Matthew D Pierson

Timothy David Anderson

Abhijeet Ashok Chachad

David Matthew Thompson

Disclosed embodiments relate to a security firewall having a security hierarchy including: secure master (SM); secure guest (SG); and non-secure (NS). There is one secure master and n secure guests. The firewall includes one secure region for secure master and one secure region for secure guests. The SM region only allows access from the secure master and the SG region allows accesses from any secure transaction. Finally, the non-secure region can be implemented two ways. In a first option, non-secure regions may be accessed only upon non-secure transactions. In a second option, non-secure regions may be accessed any processing core. In this second option, the access is downgraded to a non-secure access if the security identity is secure master or secure guest. If the two security levels are not needed the secure master can unlock the SM region to allow any secure guest access to the SM region.

Secure master and secure guest endpoint security firewall

A prefetch unit includes multiple memories; and a memory controller coupled to the multiple memories. The memory controller includes a prefetch stream filter and a prefetch buffer. The prefetch stream filter includes a first set of address slots and a set of direction prediction fields, each of which is associated with a respective one of the address slots of the first set of address slots. The prefetch buffer includes a set of buffer slots, each slot of the set of buffer slots including an address field, a direction prediction field, a data pending field, a data valid field, and a set of sub-slots configured to store data, wherein each address field of each slot of the set of buffer slots is configured to store at least a portion of an address associated with the corresponding slot.

Slot/sub-slot prefetch architecture for multiple memory requestors

This invention is a bus communication protocol. A master device stores bus credits. The master device may transmit a bus transaction only if it holds sufficient number and type of bus credits. Upon transmission, the master device decrements the number of stored bus credits. The bus credits correspond to resources on a slave device for receiving bus transactions. The slave device must receive the bus transaction if accompanied by the proper credits. The slave device services the transaction. The slave device then transmits a credit return. The master device adds the corresponding number and types of credits to the stored amount. The slave device is ready to accept another bus transaction and the master device is re-enabled to initiate the bus transaction. In many types of interactions a bus agent may act as both master and slave depending upon the state of the process.

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San Jose, CA, United States of America

Joseph R M Zbiciak