DEVICE HAVING PCI EXPRESS LINK ERROR DETECTION AND AUTOMATIC RESTORATION FUNCTION

摘要

PROBLEM TO BE SOLVED: To detect and automatically restore a link error between ICs connected by PCI Express interfaces.SOLUTION: A device includes: a register (24 or 25) for setting a time till link-up between PCI Express interfaces after reset release; a link error detection part 26 for detecting a link error in a link-up sequence; and a link restoration control part 29. When the link error detection part detects the link error in the polling state of the link-up sequence, the link restoration control part 29 returns a state to a detect state so as to try the link-up again. When the repetition number of trials becomes equal to or more than X times after the first detection of an abnormality, the link restoration control part 29 performs a link reset with respect to a link with the link error so as to try the link-up again. When the repetition number of trials becomes equal to or more than Y times after the first execution of the link reset, the link restoration control part 29 performs a control operation to reset a whole apparatus.