Method and system for enhanced management operation utilizing intermixed user level and supervisory level instructions with partial concept synchronization
US5764969A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 10, 1995 |
| Grant date | Jun 9, 1998 |
| Priority date | — |
| Expiry date | Feb 10, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F12/1475
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and system for enhanced system management operations in a superscalar data processing system. Those supervisory level instructions which execute selected privileged operations within protected memory space are first identified as not requiring a full context synchronization. Each time execution of such an instruction is initiated an enable special access (ESA) instruction is executed as an entry point to that instruction or group of instructions. A portion of the machine state register for the data processing system is stored and the machine state register is then modified as follows: a problem bit is set, changing the execution privilege state to "supervisor;" external interrupts are disabled; and access privilege state bit is set; and, a special access mode bit is set, allowing execution of special instructions. The instructions which execute the selected privileged operations within the protected memory space are then executed. A disable special access (DSA) instruction is then executed which restores the bits within the machine state register which were modified during the ESA instruction. The ESA and DSA instructions are implemented without modifying the instruction s…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.