Datasheet

Introduction
12 Datasheet
1.3.3 Direct Media Interface Gen 2 (DMI2)
• Serves as the chip-to-chip interface to the PCH
• The DMI2 port supports x4 link width and only operates in a x4 mode when in DMI2
• Operates at PCI Express* 1.0 or 2.0 speeds
• Transparent to software
• Processor and peer-to-peer writes and reads with 64-bit address support
• APIC and Message Signaled Interrupt (MSI) support. Will send Intel-defined “End of
Interrupt” broadcast message when initiated by the processor.
• System Management Interrupt (SMI), SCI, and SERR error indication
• Static lane numbering reversal support
• Supports DMI2 virtual channels VC0, VC1, VCm, and VCp
Figure 1-2. PCI Express* Lane Partitioning and Direct Media Interface Gen 2 (DMI2)
Transaction
Link
Physical
0…3
X4
DMI
Port 0
DMI / PCIe
4…7
X4
Port 1b
Transaction
Link
Physical
0…3
X4
Port 1a
Port 1
(IOU2)
PCIe
X8
Port 1a
8…11
Transaction
Link
Physical
0…3
Port 2
(IOU0)
PCIe
X4
Port 2b
X4
Port 2a
X8
Port 2a
X4
Port 2d
X4
Port 2c
X8
Port 2c
X16
Port 2a
12..154…7 8…11
Transaction
Link
Physical
0…3
Port 3
(IOU1)
PCIe
X4
Port 3b
X4
Port 3a
X8
Port 3a
X4
Port 3d
X4
Port 3c
X8
Port 3c
X16
Port 3a
12..154…7