Intel ITANIUM ARCHITECTURE - SOFTWARE DEVELOPERS MANUAL VOLUME 1 REV 2.3 Manual page 529

PAL encapsulates those processor functions that are likely to change on an
implementation to implementation basis so that SAL firmware and operating system
software can maintain a consistent view of the processor. These include
non-performance critical functions dealing such as processor initialization, configuration
and error handling.
PAL consists of two main components:
• Entrypoints, which are invoked directly by hardware events such as reset, init and
machine checks. These interruption entrypoints perform functions such as
processor initialization and error recovery.
• Procedures, which may be called by higher level firmware and software to obtain
information about the identification, configuration, and capabilities of the processor
implementation; to perform implementation-dependent functions such as cache
initialization; or to allow software to interact with the hardware through such
functions as power management or enabling/disabling processor features.
11.1.2 Firmware Entrypoints
Figure 11-2.
Reset
Power-On
Initialize
Error
PMI
Resume
Volume 2, Part 1: Processor Abstraction Layer
Firmware Entrypoints Logical Model
PAL
Firmware Recovery Complete
Bootstrap Processor (BSP)
PALE_RESET
Application
Processors
SAL_BOOT_RENDEZ
PALE_INIT
PALE_CHECK
Rendezvous Complete
PALE_PMI
SAL UEFI
BSP
SAL_RESET
UEFI Boot Manager
(APs)
SAL_INIT
Bootstrap Processor (BSP)
SAL_CHECK
MC_Rendezvous
Interrupt
SAL_MC_RENDEZ
Application Processors (APs)
SALE_PMI
OS
BSP
OS_LOADER
Wake Up
OS_INIT
OS_MCA
Wake Up
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