Intel CM8062101038606 DMI2/PCI Express* Interface, Intel QuickPath Interconnect, 3 DMI2 Link Down

Interfaces

256 bytes of a logical device's configuration space) and an extended PCI Express* region (which consists of the remaining configuration space). The PCI-compatible region can be accessed using either the mechanisms defined in the PCI specification or using the enhanced PCI Express* configuration access mechanism described in the PCI Express* Enhanced Configuration Mechanism section.

The PCI Express* Host Bridge is required to translate the memory-mapped PCI Express* configuration space accesses from the host processor to PCI Express* configuration cycles. To maintain compatibility with PCI configuration addressing mechanisms, it is recommended that system software access the enhanced configuration space using 32-bit operations (32-bit aligned) only.

See the PCI Express* Base Specification for details of both the PCI-compatible and PCI Express* Enhanced configuration mechanisms and transaction rules.

2.3DMI2/PCI Express* Interface

Direct Media Interface 2 (DMI2) connects the processor to the Platform Controller Hub (PCH). DMI2 is similar to a four-lane PCI Express* supporting a speed of 5 GT/s per lane. This interface can be configured at power-on to serve as a x4 PCI Express* link based on the setting of the SOCKET_ID[1:0] and FRMAGENT signal for processors not connected to a PCH.

Note: Only DMI2 x4 configuration is supported.

2.3.1DMI2 Error Flow

DMI2 can only generate SERR in response to errors, never SCI, SMI, MSI, PCI INT, or GPE. Any DMI2 related SERR activity is associated with Device 0.

2.3.2Processor/PCH Compatibility Assumptions

The processor is compatible with the PCH and is not compatible with any previous MCH or ICH products.

2.3.3DMI2 Link Down

The DMI2 link going down is a fatal, unrecoverable error. If the DMI2 data link goes to data link down, after the link was up, then the DMI2 link hangs the system by not allowing the link to retrain to prevent data corruption. This is controlled by the PCH.

Downstream transactions that had been successfully transmitted across the link prior to the link going down may be processed as normal. No completions from downstream, non-posted transactions are returned upstream over the DMI2 link after a link down event.

2.4Intel QuickPath Interconnect

The Intel QuickPath Interconnect is a high speed, packetized, point-to-point interconnect used in the 2nd Generation Intel(r) Core(TM) Processor Family. The narrow high-speed links stitch together processors in distributed shared memory and integrated I/O platform architecture. It offers much higher bandwidth with low latency. The Intel QuickPath Interconnect has an efficient architecture allowing more interconnect performance to be achieved in real systems. It has a snoop protocol

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