Patent ID: 7117126

Claim:
A data processing system comprising: a first data processing device, a second data processing device, and a third data processing device; a communication fabric including at least a first communication link coupling the first and second data processing devices for point-to-point communication therebetween and a second communication link coupling the second and third data processing devices for point-to-point communication therebetween; fabric maintenance logic that generates a recalibration signal; fabric control logic coupled to the communication fabric, wherein the fabric control logic, responsive to the recalibration signal, transmits a halt packet via the first and second communication links to multiple ones of the first, second and third data processing devices to concurrently idle transfer of system data on the first and second communication links between the first, second, and third data processing devices; and a collection of tunable interfaces within the first, second and third data processing devices that communicates test data via the first and second communication links while transmission of system data via the first and second communication links is idle, wherein said collection of tunable interfaces recalibrates a parameter of transmission of system data via the communication fabric in response to communication of the test data over the first and second communication links.