Pci Express Bus; Pcie Slots - IBM BladeCenter PS703 Technical Overview And Introduction

PS704
base
planar
PS704
SMP
planar
Figure 2-13 PS704 I/O Hub subsystem architecture

2.7.1 PCI Express bus

PCIe uses a serial interface and allows for point-to-point interconnections between devices
using a directly wired interface between these connection points. A single PCIe serial link is a
dual-simplex connection using two pairs of wires, one pair for transmit and one pair for
receive, and can only transmit one bit per cycle. It can transmit at the extremely high speed of
5 Gbps. These two pairs of wires is called a lane. A PCIe link might be comprised of multiple
lanes. In such configurations, the connection is labeled as x1, x2, x8, x12, x16, or x32, where
the number is the number of lanes.
The PCIe expansion card options for the PS700, PS701, PS702, PS703, and PS704 blades
support Extended Error Handling (EEH). The card ports are routed through the BladeCenter
mid-plane to predetermined I/O switch bays. The switches installed in these switch bays must
match the type of expansion card installed, Ethernet, Fibre Channel, and so forth.

2.7.2 PCIe slots

The two PCIe slots are connected to the three x8 Gen2 PCIe links on the GX++
multifunctional host bridge chip. One of the x8 links supports the CIOv connector and the
other two links support the CFFh connector on the blade. All PCIe slots are Enhanced Error
Handling (EEH). PCI EEH-enabled adapters respond to a special data packet generated from
the affected PCIe slot hardware by calling system firmware, which examines the affected bus,
allows the device driver to reset it, and continues without a system reboot. For Linux, EEH
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IBM BladeCenter PS703 and PS704 Technical Overview and Introduction
BCM5387 To chassis
Ethernet I/O bays
1 & 2
switch
BCM5709
x4 Gen1
Gigabit
Ethernet
GX++ bus
To processor 0
GX++ bus
To processor 0
x4 Gen1
BCM5709
Gigabit
Ethernet
To chassis
I/O bays
1 & 2
PCIe to
PCI controller
x1 Gen1
Two x8 Gen2
CFFh I/O connector
P7IOC
I/O hub
x8 Gen2
CIOv I/O connector
SAS pass-through
HDD/SSD connector
x8 Gen1
3Gb
HDD/SSD connector
SAS
SAS pass-through
x8 Gen2
CIOv I/O connector
P7IOC
I/O hub
Two x8 Gen2
CFFh I/O connector
To
USB
media
tray