Eeh Adapters And Partitioning; I/O Drawer Attachment - IBM p5 590 System Handbook

slots capable of supporting 3.3 V signaling PCI or PCI-X adapters operating at
speeds up to 133 MHz. Each I/O drawer planar incorporates two integrated
Ultra3 SCSI adapters for direct attachment of the two 4-pack blind-swap
backplanes in that half of the drawer and these adapters do not support external
SCSI device attachments. Each half of the I/O drawer is powered separately.
FC 5791 is a 7040-61D with 16 disk bays and FC 5794 is a 7040-61D with eight
disk bays.

2.7.1 EEH adapters and partitioning

The p5-590 and p5-595 systems are currently only orderable with adapters that
support EEH. Support of a non-EEH adapter (OEM adapter) is only possible
when the system has not been configured for partitioning. This is the case when
a new system is received, for example, and it is in full system partition and is
planned to be used without an HMC. EEH will be disabled for that adapter upon
system initialization.
When the platform is prepared for partitioning or is partitioned the POWER
Hypervisor prevents disabling EEH upon system initialization. Firmware in the
partition will detect any non-EEH device driver that are installed and not
configure them. Therefore, all adapters in p5 systems must be EEH capable in
order to be used by a partition. This applies to I/O installed in I/O drawers
attached to a Sserver p5 system.
A client does not need to actually create more than a single partition to put the
platform in a state where the Hypervisor considers it to be partitioned. The
platform becomes partitioned (in general, but also in specific reference to EEH
enabled by default) as soon as the client attaches an HMC and performs any
function that relates to partitioning. Simple hardware service operations do not
partition the platform, so it is not simply connecting an HMC that has this affect.
But, modifying any platform attributes related to partitioning (such as booting
under HMC control to only PHYP standby, and suppressing autoboot to the
pre-installed OS partition) results in a partitioned platform, even if the client does
not actually create additional partitions.
All Sserver p5 platform IO slots are managed the same with respect to EEH.

2.7.2 I/O drawer attachment

System I/O drawers are connected to the p5-590 and p5-595 CEC using RIO-2
loops. Drawer connections are made in loops to help protect against a single
point-of-failure resulting from an open, missing, or disconnected cable. Systems
with non-looped configurations could experience degraded performance and
serviceability. The system has a non-looped configuration if only one RIO-2 path
is running.
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