Intel E5-4600 manual Processor Error Handling, Originator Retry and Timeout Policy, Link Init Mode

2.5.3.7.2Link Init Mode

In cases where the socket is not one Intel QPI hop away from the Firmware Agent socket, or a working link to the Firmware Agent socket cannot be resolved, the socket is placed in Link Init mode. The socket performs a minimal amount of internal configuration and waits for complete configuration by BIOS.

2.5.3.8Processor Error Handling

Availability of PECI services may be affected by the processor PECI client error status. Server manageability requirements place a strong emphasis on continued availability of PECI services to facilitate logging and debug of the error condition.

•Most processor PECI client services are available in the event of a CAT_ERR_N assertion though they cannot be guaranteed.

•The Ping(), GetDIB(), GetTemp(), RdPkgConfig() and WrPkgConfig() commands will be serviced if the source of the CAT_ERR_N assertion is not in the processor power control unit hardware, firmware or associated register logic. Additionally, the RdPCIConfigLocal() and WrPCIConfigLocal() commands may also be serviced in this case.

•It is recommended that the PECI originator read Index 0/Parameter 5 using the RdPkgConfig() command to debug the CAT_ERR_N assertion.

—The PECI client will return the 0x91 completion code if the CAT_ERR_N assertion is caused by the PCU hardware, firmware or associated logic errors. In such an event, only the Ping(), GetTemp() and GetDIB() PECI commands may be serviced. All other processor PECI services will be unavailable and further debug of the processor error status will not be possible.

—If the PECI client returns a passing completion code, the originator should use the response data to determine the cause of the CAT_ERR_N assertion. In such an event, it is also recommended that the PECI originator determine the exact suite of available PECI client services by issuing each of the PECI commands.

The processor will issue ‘timeout’ responses for those services that may not be available.

—If the PECI client continues to return the 0x81 completion code in response to multiple retries of the RdPkgConfig() command, no PECI services, with the exception of the Ping(), GetTemp() and GetDIB(), will be guaranteed.

•The RdIAMSR() command may be serviced during a CAT_ERR_N assertion though it cannot be guaranteed.

2.5.3.9Originator Retry and Timeout Policy

The PECI originator may need to retry a command if the processor PECI client responds with a ‘response timeout’ completion code or a bad Read FCS. In each instance, the processor PECI client may have started the operation but not completed it yet. When the 'retry' bit is set, the PECI client will ignore a new request if it exactly matches a previous valid request.

The processor PECI client will not clear the semaphore that was acquired to service the request until the originator sends the ‘retry’ request in a timely fashion to successfully retrieve the response data. In the absence of any automatic timeouts, this could tie up shared resources and result in artificial bandwidth conflicts.

Intel® Xeon® Processor E5-1600/E5-2600/E5-4600 Product Families	73
Datasheet Volume One