Multi-master bus system performing atomic transactions and method of operating same

A multi-master bus system comprising

• a bus;
• a plurality of bus devices coupled to the bus, including masters having logic for requesting the bus for an atomic transaction, and slaves;
• a memory controller coupled to the bus for controlling the data exchange between the bus devices, the memory controller having memory for storing a transaction type value with respect to each slave;
• and
• an arbiter coupled to the bus masters and to the memory controller for performing bus arbitration, the arbiter having logic for conditionally subsequently granting the bus to a master for performing an atomic transaction if the transaction type value of the slave is of a predefined value;
• wherein the arbiter comprises logic for increasing a priority of the master of the atomic transaction due to a signal from the memory controller until the arbitration for the transaction subsequent to the atomic transaction.

A multi-master bus system comprising

• a bus;
• a plurality of bus devices coupled to the bus, including masters having logic for requesting the bus for an atomic transaction, and slaves;
• a memory controller coupled to the bus for controlling the data exchange between the bus devices, the memory controller having memory for storing a transaction type value with respect to each slave;
• and
• an arbiter coupled to the bus masters and to the memory controller for performing bus arbitration, the arbiter having logic for conditionally subsequently granting the bus to a master for performing an atomic transaction if the transaction type value of the slave is of a predefined value;
• wherein the arbiter comprises logic for blocking the arbitration process and repeating the result of the previous arbitration process.

A method of operating a bus, the method comprising the steps of:

• defining a transaction type with respect to each slave;
• arbitrating of the bus by an arbiter;
• granting the bus to the master who wins the arbitration;
• performing an initiating transaction by the initiating master on the bus;
• and
• if the transaction type is of a predetermined type,
• granting the bus subsequently to the initiating master for performing a closing transaction by the initiating master on the bus;
• and
• when the transaction type is of the predetermined type,
• masking bus request signals from other masters than the initiating master at least until the bus is granted to the initiating master for the closing transaction.

A method of operating a bus, the method comprising the steps of:

• defining a transaction type with respect to each slave;
• arbitrating of the bus by an arbiter;
• granting the bus to the master who wins the arbitration;
• performing an initiating transaction by the initiating master on the bus;
• and
• if the transaction type is of a predetermined type,
• granting the bus subsequently to the initiating master for performing a closing transaction by the initiating master on the bus;
• and
• when the transaction type is of the predetermined type,
• increasing a priority of the initiating master while arbiting the bus for the closing transaction.

A method of operating a bus, the method comprising the steps of:

• defining a transaction type with respect to each slave;
• arbitrating of the bus by an arbiter;
• granting the bus to the masters who wins the arbitration;
• performing an initiating transaction by the initiating master on the bus;
• and
• if the transaction type is of a predetermined type,
• granting the bus subsequently to the initiating master for performing a closing transaction by the initiating master on the bus;
• and
• when the transaction type is of the predetermined type,
• blocking the arbitration process and repeating the result of the previous arbitration process at least until the bus is granted to the initiating master for the closing transaction.

A method of operating a bus, the method comprising the steps of:

• defining a transaction type with respect each slave;
• arbitrating of the bus by an arbiter;
• granting the bus to the master who wins the arbitration;
• performing an initiating transaction by the initiating master on the bus;
• and
• if the transaction type is of a predetermined type,
• granting the bus subsequently to the initiating master for performing a closing transaction by the initiating master on the bus;
• and
• wherein the bus is granted to the master of the initiating transaction for a closing transaction due to a signal from the memory controller.