Bandwidth limiting on generated PCIe packets from debug source

• US 8,898,359 B2
• Filed: 02/26/2013
• Issued: 11/25/2014
• Est. Priority Date: 06/20/2012
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Freking, Ronald E., McGlone, Elizabeth A., Spach, Daniel R., Wollbrink, Curtis C.
• Primary Examiner(s): Tsai, Henry
• Assistant Examiner(s): Hassan, Aurangzeb
• Application Number:
  US13/777,154
• Publication Number:
  US 20130346802A1
• Time in Patent Office: 637 Days
• Field of Search: None
• US Class Current: 710/113
• CPC Class Codes: G06F 11/263 Generation of test inputs, e.g. test vectors, patterns or sequences ; with adaptation of the tested hardware for testability with external testers
• CPC Class Codes: G06F 13/00 Interconnection of, or transfer of information or other signals between, memories, input/output devices or central processing units interface circuits for specific input/output devices G06F3/00 ; multiprogram control therefor G06F9/46; multiprocessor systems G06F15/16
• CPC Class Codes: G06F 13/1605 based on arbitration arbitration in handling access to a common bus or bus system G06F13/36
• CPC Class Codes: G06F 13/36 for access to common bus or bus system
• CPC Class Codes: G06F 2213/0026 PCI express

Abstract

Method, circuit, and system for performing an operation for regulating bandwidth, the operation comprising receiving at a memory, debug data packets and functional data packets for transmittal on a shared bus. The operation then transmits, via the shared bus, the functional data packets and one or more of the debug data packets according to a predefined ratio of debug data packets to functional data packets. The operation then drops one or more of the received debug data packets at the memory, and maintains a count of the one or more dropped debug data packets. The operation then updates the predefined ratio based on the count, and uses the updated predefined ratio to transmit the functional data packets and one or more of the debug data packets.

Claims

1. A method for regulating bandwidth, comprising:

receiving at a memory, debug data packets and functional data packets for transmittal on a shared bus;

transmitting, via the shared bus, the functional data packets and one or more of the debug data packets according to a predefined ratio of debug data packets to functional data packets maintained by an arbiter;

dropping one or more of the received debug data packets in the memory;

maintaining a count of the one or more dropped debug data packets;

updating, by the arbiter, the predefined ratio based on the count; and

using the updated predefined ratio to transmit the functional data packets and one or more of the debug data packets on the shared bus.

2. The method of claim 1, further comprising:

upon determining that a number of sequential data packets of a first type transmitted on the shared bus exceeds a maximum threshold, transmitting at least one packet of a different, second type, on the shared bus, wherein the first type and the second type are selected from functional data packets and debug data packets, wherein if the first type is functional data packets, the second type is debug data packets, wherein if the first type is debug data packets, the second type is functional data packets.

3. The method of claim 1, wherein the functional data packets are not dropped from the memory.

4. The method of claim 1, wherein dropping one or more received debug data packets comprises not transmitting the one or more received debug data packets via the bus.

5. The method of claim 1, wherein dropping one or more received debug data packets is based on at least one of:

(i) comparing a usage of the memory to a predefined capacity threshold, and (ii) comparing an amount of time the one or more received debug data packets have remained in the memory to a predefined timing threshold.

6. The method of claim 1, wherein the arbiter updates the predefined ratio by comparing the count to a predefined drop threshold.

7. The method of claim 1, further comprising:

transmitting the count of the dropped debug data packets to a user interface, wherein the count is used by the arbiter to update the predefined ratio; and

before updating the predefined ratio, receiving, by the arbiter, the updated predefined ratio.