IBM AS/400e, User Handbook Manual

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AS/400 System Architecture: Underlying Strength of the AS/400e
20
AS/400e System Handbook
Hot-Plugging
The term “hot-plug PCI” is used by the computing industry for a wide range of purposes.
Primarily, hot-plug PCI refers to the technology that allows users to install and remove PCI
devices while the computer is running.
A method must be in place to inform the operating system of insertion and removal events.
Driven by the demand for the highest possible availability, PCI hot-plugging is now available
on the new AS/400e servers with V4R5 on all 8xx and some of the 270 models. A brief
description of the way it is implemented on the AS/400e follows.
Hot-plugging in the AS/400e is made possible by power control to individual card slots, so
that PCI IOPs or IOAs can be added, removed, or replaced while the system remains active.
In most cases, IOA configurations can be changed while other IOAs on the same IOP remain
operational. Hot-plug implementation for the AS/400 system for V4R5 is illustrated in the
following figure.
In V4R5, the interface for hot-plugging actions uses the Hardware Service Manager in the
System Service Tools, or a subset of Dedicated Service Tools (depending on which tool you
have started). In limited paging environment, Dedicated Service Tools communicates directly
with V4R5 System Licensed Internal Code (SLIC).
Conventional SLIC and hardware control power and bus connections on the PCI slots. In
V4R5, certain hot-plug AS/400 SLIC and hardware communicate with the Standard PCI
hot-plug interface signals.
OS/400
User Interface
SST / DST
Hardware
Service
Manager
functions
AS/400 V4R5
SLIC/ HW drivers
SYSTEM HW
P C I B U S
Standard
Hot-Plug Hardware
Interface
P O W E R C O N T R O L