Kontron AM4120 IPMI Firmware - Manual (Page 36)

Functional Description AM4120 IPMI Firmware
Page 30 ID 1045-9586, Rev. 1.0
6.2 FRU Data Update
Update of the FRU data can be done via regular IPMI FRU device commands. The correct FRU
data must be prepared at the factory.
7. E-Keying
E-Keying has been defined in the AMC.0 R2.0 Specification to prevent module damage, pre-
vent malfunctions, and verify bay connection compatibility. Therefore, the FRU data of an AMC
module contains PICMG-defined records which describe the module’s AMC interoperability:
• Module Current Requirements Record
• Clock Configuration Record, for the PCI Express reference clock
• AMC Point-to-point Record, describing module’s AMC port capabilities
The IPMI commands
Set AMC Port State
and
Get AMC Port State
defined by the
AMC.0 specification are used by the carrier or MCH for either granting or rejecting the E-Keys
(i.e. enabling or disabling of AMC ports during E-Keying).
Which AMC port connections are activated is decided during E-Keying. The information which
AMC port is enabled or not, can be directly read from the board’s E-Keying configuration reg-
isters (IAKEY0, IAKEY1 and IAKEY2) at addresses 0x298 / 0x299 / 0x29Ah.
7.1 Board Configuration for E-Keying
The AM4120 supports either a Serial RapidIO interface (default) or a PCI Express interface in
the AMC port Fat Pipes region.
The required interface settings must be configured via DIP Switch SW2.
For further information, refer to the AM4120 User Guide, Chapter 4.1 DIP Switch Configuration.
7.2 PCI Express Reference Clock - FCLKA
Both sides (Root Complex and Endpoint) of a PCI Express connection should be driven by a
common reference clock. The PCI Express reference clock may be generated locally by the
module or acquired from the AMC connector.
When the AM4120 is configured as PCI Express Root Complex, it may act either as clock re-
ceiver or as clock source. If configured as PCI express Endpoint, the AM4120 is acting as clock
receiver only. Both are described by the Clock Configuration Record (for the PCI Express ref-
erence clock) and defined by the “AMC.1 R2.0, PCI Express on AMC” specification.
The DIP Switch SW3 can be used to overwrite the clock configuration (clock receiver, clock
source, etc.) regardless of the E-Keying results. Please refer to the AM4120 User Guide for de-
tails.
Clock Receiver:
The PCI Express reference clock provided by the carrier may be slightly modulated (SSC -
Spread Spectrum Clock). The FRU E-Keying data for the AM4120 contains two AMC link de-
scriptors for each PCI Express channel, one with SSC (priority 1) or with non-SSC (priority 2).
The carrier’s IPMC selects the “matching” link descriptor (SSC or non-SSC) during E-Keying
using the
Set AMC Port State
command.