Lsi Logic Corporation

Lsi Corporation

Simon Bewick

Christopher M Giles

Kalvin E Williams

A circuit generally comprising a first memory, a processor and a logic block is disclosed. The first memory may store (i) a write instruction to store a non-highest security value of at least three security values in a register and (ii) a jump instruction to a second memory. The processor may have a pipeline and may be configured to (i) bootstrap to the first memory while the register stores a highest security value of the security values and (ii) execute the jump instruction following the write instruction. The logic block may be configured to (i) detect the write instruction in an execution stage of the pipeline and (ii) store the non-highest security value in the register in response to detecting the write instruction in a write back stage of the pipeline.

Precise exit logic for removal of security overlay of instruction space

A circuit generally comprising a plurality of master modules and a supervisor module is disclosed. The supervisor module may be configured to (i) detect a target address and a particular master module of the master modules initiating a transaction on a bus, (ii) identify a predetermined authorization in response to the particular master module, the target address and a current security mode of at least three security modes and (iii) subvert the transaction in response to the predetermined authorization restricting the transaction.

Security supervisor governing allowed transactions on a system bus

A circuit generally comprising a logic module and a security module is disclosed. The logic module may be configured to set a plurality of values to a plurality of predetermined values respectively while in a scan mode. The security module may be configured to (i) disable a scan capability of the values while in a non-lowest security mode of at least three security modes and (ii) enabling the scan capability while in a lowest security mode of the security modes.

Scan and boundary scan disable mechanism on secure device

A circuit generally comprising a debug port and a processor is disclosed. The processor may be configured to (i) bootstrap to a first memory, (ii) disable said debug port while in a first mode of at least three modes, (iii) authenticate said debug port while in a second mode of said modes and (iv) disable said debug port in response to failing said authentication.

Debug port disable mechanism

A circuit generally comprising a first memory, a second memory and a processor is disclosed. The first memory may store an instruction to read an updated security value of at least three security values. The second memory may store (i) the updated security value and (ii) information related to security of the circuit. The processor may be configured to (i) execute the instruction while a register stores a highest security value of the security values, (ii) copy the information from the second memory to a third memory in response to the update security value being greater than a current security value of the security values stored in the third memory and (iii) ignore the information in the second memory in response to the updated security value being no greater than the current security value.

Use of EEPROM for storage of security objects in secure systems

In order to descramble sections of scrambled data interleaved with sections of unscrambled data in a transport stream of broadcast video data, while leaving the sections with the original timing relationship in the transport stream, a common data flow path ( ) is provided both for sections of scrambled data and sections of unscrambled data and signal path loops ( ) including cipher means ( ) to enable the descrambling of scrambled data, and a control state machine for controlling the flow of data through said common data flow path and said signal path loops to enable passage of unscrambled data sections and descrambling of scrambled data sections, while maintaining the desired relative positions of the data sections.

Digital video broadcasting

In order to implement the Digital Video Broadcasting descrambling algorithm in the context of MPEG compressed data streams containing interleaved sections of scrambled and unscrambled data, at a data rate of 60 MBits/sec with a clock of 2.7 MHz, a stream cipher has an input to receive scrambled video data, and an output coupled to a block cipher for providing descrambled data, the stream cipher comprises shift register means for holding input data coupled to a first mapping logic mechanism comprising at least a first logic means and a second logic means coupled in sequence and arranged to carry out similar logical steps, and the block cipher means comprising shift register means for holding the output of the stream cipher means and a second logic mapping mechanism, comprising at least a first logic means, a second logic means, a third logic means and a fourth logic means coupled in sequence being arranged to carry out similar logical steps.

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Finchampstead, United Kingdom

Simon Bewick