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AR# 50232

Virtex-7 FPGA Gen3 Integrated Block for PCI Express v1.1 (ISE 14.1/Vivado 2012.1) - Secondary PCI Express Extended Capability not enabled by default in Gen3 Core Configuration


Version Found: v1.1
Version Resolved and other Known Issues: See (Xilinx Answer 47441)

According to PCI Express Base Specification v3.0, Secondary PCI Express Extended Capability must be enabled by default in Gen3 core configuration. This is not the case in the current core release. This issue could lead the core to link up in Gen2 speed instead of Gen3 speed.


This is a known issue to be fixed in a future release of the core. To work around this issue, theNextCap pointer of the last enabled extended Capability must point to the Secondary PCIe Cap (300h). If no additional extended capabilities are enabled, make the following modification:


*_AER_CAP_NEXTPTR = 12'h000


*_AER_CAP_NEXTPTR = 12'h300

Note: "Version Found" refers to the version the problem was first discovered. The problem might also exist in earlier versions, but no specific testing has been performed to verify earlier versions.

Revision History
01/08/2013 - Added workaround
06/04/2012 - Initial release

Linked Answer Records

Master Answer Records

AR# 50232
Date Created 06/06/2012
Last Updated 02/03/2013
Status Active
Type Known Issues
  • Vivado - 2012.1
  • ISE Design Suite - 14.1
  • Virtex-7 FPGA Gen3 Integrated Block for PCI Express (PCIe)