CN103136142A - Bus arbitration method - Google Patents

Abstract

The invention provides a bus arbitration method comprises a bus and a system device mounted on the bus. The bus is provided with a bus arbitration logic and a device priority logic. The bus arbitration method includes the specific steps that the system device sends a bus arbitration request application, and the bus occupies in sequence after the bus arbitration passes; when some device requests priority, the device requesting priority sends a request to the bus, and the device has the priority for occupancy after the bus permits; when the device finishes prior occupancy, the bus arbitration order is restored; and when the bus finishes the occupancy, the bus occupancy is released and the bus waits for next application. Compared with the prior art, the bus arbitration method has the advantages of being capable of improving the running speed of a system, conveniently allowing the system to provide fast bus arbitration, ensuring arbitration process in order and avoiding long waiting time.

Description

A kind of method of bus arbitration

Technical field

The present invention relates to field of computer technology, specifically utilize a kind of method of bus arbitration.

Background technology

Along with the fast development of microelectric technique, on same chip, integrated increasing functional module, interconnect by bus mode between each module of chip internal and communicate by letter.Therefore, on-chip bus arbitration framework also becomes as the key factor that affects chip-on communication efficient the bottleneck that the system for restricting performance improves.How to design a efficient on-chip bus arbitration device, solve main equipment to the competition conflict of bus resource, become the key of this problem.Design a efficient bus arbiter, at first must design a kind of efficient arbitration algorithm, and then its hardware is realized just can designing corresponding arbitration device.In current SOC chip, on-chip bus is the most critical system resource that collaborative a plurality of equipment carry out parallel processing, is also one of bottleneck of system performance.The arbitration of on-chip bus is for the competition that solves many equipment shared bus resource and reasonable fair efficient allocation bus resource.Bus arbitration is the necessary guarantee that improves total line use ratio.

Summary of the invention

Technical assignment of the present invention is to solve the deficiencies in the prior art, and a kind of method of bus arbitration of Simple fast is provided.

Technical scheme of the present invention realizes in the following manner, and the method for this a kind of bus arbitration comprises bus, the carry system equipment on bus, and described bus is provided with bus arbitration logic, priority facility logic, and its detailed process is:

1) system equipment sends the application of request bus arbitration, and after bus arbitration passed through, bus took, and this bus takies according to sequencing;

2) when having device request preferential, ask preferential equipment to send request to bus, bus preferentially takies after allowing;

3) preferentially take complete after, recovering step 1) in bus arbitration order;

4) complete bus and take, bus takies release, and bus is waited for application next time.

The detailed step of described step 1) is: system equipment first sends bus request, and bus arbitration logic is according to the request of fairness doctrine arbitration equipment, if request is allowed by bus, system equipment takies data bus and address bus, otherwise, need request again.

Described step 2) detailed step is: if system runs into accident, when needing certain particular device, this equipment is filed a request to the priority facility logic, and the priority facility logic gives the equipment highest priority, allows thereby obtain bus.

The beneficial effect that the present invention compared with prior art produces is:

The method of a kind of bus arbitration of the present invention has improved the travelling speed of system, facilitates system to make fast bus arbitration, and arbitrated procedure is unexpectedly orderly, avoids occurring high latency.

Description of drawings

Accompanying drawing 1 is structural representation of the present invention.

Accompanying drawing 2 is arbitrated procedure process flow diagrams of the present invention.

Embodiment

Be described in detail below below in conjunction with the method for accompanying drawing to a kind of bus arbitration of the present invention.

On common centralized arbitration logic, add the priority facility logic, as accompanying drawing 1, shown in Figure 2, a kind of method of bus arbitration now is provided, comprise bus, the carry system equipment on bus, described bus is provided with bus arbitration logic, priority facility logic, and its detailed process is:

1) system equipment sends the application of request bus arbitration, and after bus arbitration passed through, bus took, and this bus takies according to sequencing;

2) when having device request preferential, ask preferential equipment to send request to bus, bus preferentially takies after allowing;

3) preferentially take complete after, recovering step 1) in bus arbitration order;

4) complete bus and take, bus takies release, and bus is waited for application next time.

The detailed step of described step 1) is: system equipment first sends bus request, and bus arbitration logic is according to the request of fairness doctrine arbitration equipment, if request is allowed by bus, system equipment takies data bus and address bus, otherwise, need request again.

Described step 2) detailed step is: if system runs into accident, when needing certain particular device, this equipment is filed a request to the priority facility logic, and the priority facility logic gives the equipment highest priority, allows thereby obtain bus.

Claims (3)

1. the method for a bus arbitration, it is characterized in that: comprise bus, the carry system equipment on bus, described bus is provided with bus arbitration logic, priority facility logic, and its detailed process is:

1) system equipment sends the application of request bus arbitration, and after bus arbitration passed through, bus took, and this bus takies according to sequencing;

2) when having device request preferential, ask preferential equipment to send request to bus, bus preferentially takies after allowing;

3) preferentially take complete after, recovering step 1) in bus arbitration order;

4) complete bus and take, bus takies release, and bus is waited for application next time.

2. the method for a kind of bus arbitration according to claim 1, it is characterized in that: the detailed step of described step 1) is: system equipment first sends bus request, bus arbitration logic is according to the request of fairness doctrine arbitration equipment, if request is allowed by bus, system equipment takies data bus and address bus, otherwise, need request again.

3. the method for a kind of bus arbitration according to claim 1 and 2, it is characterized in that: detailed step described step 2) is: if system runs into accident, when needing certain particular device, this equipment is filed a request to the priority facility logic, the priority facility logic gives the equipment highest priority, allows thereby obtain bus.

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