Figure 1-15 Itanium Firmware Interfaces
• Processor Abstraction Layer (PAL) provides a seamless firmware abstraction between the
processor, the system software, and the platform firmware.
• System Abstraction Layer (SAL) provides a uniform firmware interface and initializes and
configures the platform.
• Extensible Firmware Interface (EFI) provides an interface between the OS and the platform
firmware.
• Advanced Configuration and Power Interface (ACPI) provides a new standard environment
for configuring and managing server systems. It moves system configuration and
management from the BIOS to the operating system and abstracts the interface between the
platform hardware and the OS software, thereby enabling each to evolve independently of
the other.
The firmware supports HP-UX 11i version 2, Linux, Windows, and OpenVMS through the
Itanium® processor family standards and extensions. It includes no operating system-specific
functionality. Every OS is presented the same interface to system firmware, and all features are
available to each OS.
NOTE: Windows Server 2003 Datacenter does not support the latest ACPI specification (2.0).
The firmware must provide legacy (1.0b) ACPI tables.
Using the acpiconfig command, the ACPI tables presented to the OS are different. The firmware
implements the standard Intel® Itanium® Processor family interfaces with some
implementation-specific enhancements that the OS can use but is not required to use, such as
page deallocation table reporting, through enhanced SAL_GET_STATE_INFO behavior.
User Interface
The Intel® Itanium® processor family firmware employs a user interface called the Pre-OS
system startup environment (POSSE). The POSSE shell is based on the EFI shell. Several commands
were added to the EFI shell to support HP value-added functionality. The new commands
encompass functionality similar to BCH commands on PA-RISC systems. However, the POSSE
shell is not designed to encompass all BCH functionality. They are separate interfaces.
Error and Event IDs
The new system firmware generates event IDs, similar to chassis codes, for errors, events, and
forward progress to the MP through common shared memory. The MP interprets, stores, and
reflects these event IDs back to running partitions. This helps in the troubleshooting process.
Firmware 45
