| commit | 948d3a65b6d164b34309625f57656cb9e8b1a908 | [log] [tgz] |
|---|---|---|
| author | Jon Mason <jon.mason@intel.com> | Thu Apr 18 17:07:36 2013 -0700 |
| committer | Jon Mason <jon.mason@intel.com> | Tue Sep 03 13:51:51 2013 -0700 |
| tree | 01afe66a33f978552f0577eb478d801e8e6a6284 | |
| parent | 1517a3f21a1dd321f16bcf44204bddff9d21abd0 [diff] |
NTB: Xeon Errata Workaround There is a Xeon hardware errata related to writes to SDOORBELL or B2BDOORBELL in conjunction with inbound access to NTB MMIO Space, which may hang the system. To workaround this issue, use one of the memory windows to access the interrupt and scratch pad registers on the remote system. This bypasses the issue, but removes one of the memory windows from use by the transport. This reduction of MWs necessitates adding some logic to determine the number of available MWs. Since some NTB usage methodologies may have unidirectional traffic, the ability to disable the workaround via modparm has been added. See BF113 in http://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/xeon-c5500-c3500-spec-update.pdf See BT119 in http://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/xeon-e5-family-spec-update.pdf Signed-off-by: Jon Mason <jon.mason@intel.com>