Data processing system for performing either a precise memory access or an imprecise memory access based upon a logical address value and method thereof
US5666509A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 24, 1994 |
| Grant date | Sep 9, 1997 |
| Priority date | — |
| Expiry date | Mar 24, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F12/1027
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A processor (10) has a data cache unit (16) wherein the data cache unit includes a memory management unit (MMU) (32). The MMU contains memory locations within transparent translation registers (TTRs), an address translation cache (40), or a table walk controller (42) which store or generate cache mode (CM) bits which indicate whether a memory access (i.e., a write operation) is precise or imprecise. Precise operations require that a first write operation or bus write instruction be executed with no other operationsnstructions executing until the first operation/instruction completes with or without a fault. Imprecise operations are operations/instruction which may be queued, partially performed, or execution simultaneously with other instructions regardless of faults or bus write operations. By allowing the logical address to determine whether the bus write operation is precise or imprecise, a large amount of system flexibility is achieved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.