IBM z13s, Technical Manual

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Chapter 4. Central processor complex I/O system structure
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4.6.1 PCIe Generation 3 fanout (FC 0173)
The PCIe Generation 3 fanout card provides connectivity to an PCIe I/O drawer by using a
copper cable. One port on the fanout card is dedicated for PCIe I/O. The bandwidth of this
PCIe fanout card supports a link rate of 16 GBps.
A 16x PCIe copper cable of 1.5 meters (4.92 ft) to 4.0 meters (13.1 ft) is used for connection
to the PCIe switch card in the PCIe I/O drawer. PCIe fanout cards are always plugged in pairs
and provide redundancy for I/O domains within the PCIe I/O drawer.
The pairs of PCIe fanout cards of a z13s Model N20 are split across the two logical nodes
within a CPC drawer (LG02 - LG06 and LG11 - LG15), or are split across two CPC drawers
for redundancy purposes.
4.6.2 HCA2-C fanout (FC 0162)
The HCA2-C fanout is used to connect to an I/O drawer by using a copper cable. The two
ports on the fanout are dedicated to I/O. Each port on the HCA2-C fanout supports a link rate
of up to 6 GBps.
A 12x InfiniBand copper cable of 1.5 meters (4.92 ft.) to 3.5 meters (11.4 ft.) is used for
connection to the IFB-MP card in the I/O drawer. An HCA2-C fanout is supported only if
carried forward with a miscellaneous equipment specification (MES) from z114, or zBC12 to
z13s server. For a new build z13s server, HCA2-C cannot be ordered.‘
4.6.3 Integrated Coupling Adapter (FC 0172)
The IBM ICA SR, introduced on the z13 and z13s platform, is a two-port fanout that is used
for short distance coupling connectivity with a new coupling channel type, the CS5. The ICA
SR uses PCIe Gen3 technology, with x16 lanes that are bifurcated into x8 lanes for coupling.
No performance degradation is expected compared to the Coupling over the InfiniBand 12x
IFB3 protocol.
The ICA SR is designed to drive distances up to 150 m and supports a link data rate of
8 GBps. It is also designed to support up to four CHPIDs per port and seven subchannels
(devices) per CHPID. The coupling links can be defined as shared between images within a
channel subsystem (CSS). They also can be spanned across multiple CSSs in a CPC. Unlike
the HCA3-O 12x InfiniBand links, the ICA SR cannot define more than four CHPIDS per port.
When Server Time Protocol (STP) is enabled, ICA SR coupling links can be defined as
timing-only links to other z13 and z13s CPCs.
The ICA SR fanout is housed in the PCIe I/O fanout slot on the z13s CPC drawer, which
supports 4-16 PCIe I/O slots. Up to 8 ICA SR fanouts and up to 16 ICA SR ports are
supported on a z13s CPC drawer, enabling greater connectivity for short distance coupling on
a single processor node compared to previous generations. The maximum number of ICA SR
fanout features is 8 per system.
PCIe fanout: The PCIe fanout is used exclusively for I/O and cannot be shared for any
other purpose.
HCA2-C fanout: The HCA2-C fanout is used exclusively for a connection to the I/O
drawer. It cannot be shared for any other purpose.