Compaq ECQD2KCTE manual Unprivileged Digital Unix PALcode, Mnemonic Operation and Description

Models: ECQD2KCTE

1 371
Download 371 pages 20.35 Kb
Page 265
Image 265

Chapter 10

Digital UNIX

The following sections specifiy the Privileged Architecture Library (PALcode) instructions that are required to support a Digital UNIX system.

10.1 Unprivileged Digital UNIX PALcode

Table 10–1describes the unprivileged Digital UNIX PALcode instructions.

Table 10–1 : Unprivileged Digital UNIX PALcode Instruction Summary

Mnemonic

Operation and Description

 

 

bpt

Break point trap

 

The bpt instruction switches mode to kernel, builds a stack frame on the kernel

 

stack, and dispatches to the breakpoint code.

bugchk

Bugcheck

 

The bugchk instruction switches mode to kernel, builds a stack frame on the

 

kernel stack, and dispatches to the breakpoint code.

callsys

System call

 

The callsys instruction switches mode to kernel, builds a callsys stack frame,

 

and dispatches to the system call code.

clrfen

Clear floating-point enable

 

The clrfen instruction writes a zero to the floating-point enable register.

gentrap

Generate trap

 

The gentrap instruction switches mode to kernel, builds a stack frame on the

 

kernel stack, and dispatches to the gentrap code.

imb

I-stream memory barrier

 

The imb instruction makes the I-cache coherent with main memory.

 

 

10–1

Page 265
Image 265
Compaq ECQD2KCTE manual Unprivileged Digital Unix PALcode, Mnemonic Operation and Description