Intel S7000FC4UR Technical Product Specification page 30

Main Board
2.2.4.1.1 INTx Emulation
For legacy compatibility, PCI-Express* provides a PCI INTx emulation mechanism to signal
interrupts to the system interrupt controller (Enterprise Southbridge 2). This mechanism is
compatible with existing PCI software.
The mechanism provides the same level and type of service as standard PCI interrupt
mechanisms. However, it uses a different hardware implementation where physical PCI
interrupt signals are virtualized as in-band PCI-Express* messages. This legacy compatibility
allows boot device support without requiring complex BIOS-level interrupt configuration/control
service stacks.
2.2.4.1.2 Message Signaled Interrupt (MSI) Support
In addition to PCI INTx compatible interrupt emulation, PCI-Express* requires support of
Message Signaled Interrupt (MSI) mechanism. The PCI-Express* MSI mechanism is compatible
with the MSI capability defined in the PCI 2.2 Specification.
2.2.4.2 PCI-Express* Expander/Switch
The PCI-Express* Expander/Switch IDT
7300 Chipset. It utilizes a single x8 PCI-Express* upstream bus and expands it into two unique
downstream x8 PCI-Express* buses. Some features of the PCI-Express* Expander used on the
main board are as follows:
24 PCI Express* lanes (2.5 Gbps), three switch ports
6 GBps (48 Gbps) aggregate switching throughput
Low latency cut-through switch architecture
Supports 128 to 2048 byte maximum payload size
One virtual channel
Fully compliant with PCI Express Base Specification Revision 1.0a
ACPI power management logic support
Port arbitration schemes utilizing round robin or weighted round robin algorithms
One port configurable as downstream port or non-transparent port
Automatic per port link width negotiation to a x8, x4, x2 or x1
Static lane reversal on all ports
Polarity inversion
Ability to load device configuration from serial EEPROM
Internal end-to-end parity protection on all TLPs ensures data integrity even in systems
that do not implement end-to-end CRC (ECRC)
ECRC passed through in transparent and non-transparent modes
Supports PCI Express* native hot-plug
Compatible with hot-plug I/O expanders used on PC motherboards
Hot-swap capable I/O
8
*
89HPES24N3A works in conjunction with the Intel
Intel order number E18291-001
Intel® Server System S7000FC4UR TPS
®
Revision 1.0