Accessing control and status register (CSR)

A system comprising:

• a source agent, wherein the source agent is to initiate a transaction,
• a target agent, wherein the target agent is to complete the transaction, and
• an interconnect fabric, wherein the interconnect fabric includes a plurality of directory agents, a controller, and a parser, wherein the source agent and the target agent are coupled to the interconnect fabric, the plurality of directory agents each including a memory map to indicate mapping of a plurality of address ranges to identifiers of control and status registers of a plurality of heterogeneous agents,
• wherein the controller is to generate the memory map,
• wherein the parser is to identify a directory agent, of the plurality of directory agents, in response to receiving the transaction from the source agent via a table stored in the parser that associates the directory agents with the heterogeneous agents,
• wherein the directory agent is to,
• process the transaction initiated by the source agent to identify the target agent and a control and status register within the target agent using a first field of the transaction to which the transaction is to be sent, and
• send the transaction to the target agent, and
• wherein the plurality of directory agents in the interconnect fabric provide a directory based distributed control and status register access mechanism.

A system comprising:

• a source agent to initiate a transaction;
• a target agent to complete the transaction, and including a control and status register mechanism coupled to a bus complex, at least one control and status register endpoint coupled to the bus complex and including a master lock register, and a control and status register coupled to the at least one control and status register endpoint;
• and
• an interconnect fabric to couple the source agent and the target agent and including a controller, a parser, and a plurality of directory agents each including a memory map to indicate mapping of a plurality of address ranges to identifiers of control and status registers of a plurality of heterogeneous agents including the source agent and the target agent, wherein the parser is to identify a directory agent of the plurality of directory agents responsive to the transaction via a table stored in the parser that associates the directory agents with the heterogeneous agents, and wherein the identified directory agent is to process the transaction to identify the target agent and the control and status register using a first field of the transaction and send the transaction to the target agent, and wherein the plurality of directory agents in the interconnect fabric provide a directory based distributed control and status register access mechanism.