Token based DMA
US6820142B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 14, 2000 |
| Grant date | Nov 16, 2004 |
| Priority date | — |
| Expiry date | Feb 11, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/28
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and system for accessing a shared memory in a deterministic schedule. In one embodiment, a system comprises a plurality of processing elements and a system I/O controller where each processing element and system I/O controller comprises a DMA controller. The system further comprises a shared memory coupled to each of the plurality of processing elements where the shared memory comprises a master controller. The master controller may then issue tokens to DMA controllers to grant the right for the associated processing elements and system I/O controller to access the shared memory at deterministic points in time. Each token issued by the master controller grants access to the shared memory for a particular duration of time at a unique deterministic point in time. A processing element or system I/O controller may access the shared memory upon the associated DMA controller relinquishing to the master controller the token that grants the right to access the shared memory at that particular time. The master controller may then reissue the relinquished token back to the DMA controller associated with the processing element or system I/O controller that accessed the shared memory …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.