I/O CIRCUIT AND DATA TRANSMISSION CONTROL METHOD

• US 20170163543A1
• Filed: 12/14/2015
• Published: 06/08/2017
• Est. Priority Date: 12/04/2015
• Status: Active Grant

• Current Assignee: Via Alliance Semiconductor Co., Ltd.
• Original Assignee: Via Alliance Semiconductor Co., Ltd.
• Inventors: WANG, Wei-Lin, SHEN, Peng, LAI, Jiin, LI, Ziyang, KANG, Xiaoliang
• Granted Patent: US 9,894,001 B2
• Time in Patent Office: Days
• CPC Class Codes: H04L 45/745 Address table lookup; Address filtering
• CPC Class Codes: H04L 47/215 using token-bucket
• CPC Class Codes: H04L 49/9005 using dynamic buffer space allocation

Abstract

An I/O circuit includes buffers, a storage module, accumulators, timers, and an arbiter. Each buffer corresponds to a respective virtual channel. Each buffer corresponds to a respective token bucket, and outputs a normal transmission request according to the amount of tokens and an accumulating signal. The storage module stores a lookup table including a plurality of weightings. Each accumulator corresponds to a respective buffer, accumulates a data volume according to the corresponding weighting, and outputs the accumulating signal. Each timer corresponds to a respective buffer, times waiting period after the corresponding buffer outputs the normal transmission request, and outputs a time-out transmission request when the waiting period exceeds a predetermined period.

The arbiter receives the time-out transmission requests and the normal transmission requests, and selects one of the buffers from all of the time-out transmission requests and the normal transmission requests.

Claims

1. An I/O circuit, adapted to a computer system, comprising:

a plurality of buffers, each buffer has a token bucket, and each buffer outputs a normal transmission request according to an amount of tokens in the token bucket and an accumulating signal;

a storage module, storing a lookup table, wherein the lookup table comprises a plurality of weightings respectively corresponding to different types of data;

a plurality of accumulators, each accumulator corresponding to one from among the plurality of buffers, wherein each accumulator accumulates a data volume output from the corresponding buffers according to the corresponding weighting, and outputs the accumulating signal according to the accumulated data volume;

a plurality of timers, each timer corresponding to one from among the plurality of buffers, wherein each timer times waiting period after the corresponding buffer outputs the normal transmission request, and outputs a time-out transmission request when the waiting period exceeds a predetermined period; and

an arbiter, configured to receive the time-out transmission requests and the normal transmission requests, and select one of the buffers from all of the time-out transmission requests and the normal transmission requests to make the selected buffer outputs a data packet.

2. The I/O circuit as claimed in claim 1, wherein when the arbiter receives at least one time-out transmission request and at least one normal transmission request during transmission of the data packet, the arbiter selects the buffer corresponding to the time-out transmission request.

3. The I/O circuit as claimed in claim 1, wherein when the arbiter receives the plurality of normal transmission requests, the arbiter selects one of the buffers according to the weightings.

4. The I/O circuit as claimed in claim 1, wherein when the arbiter receives the plurality of time-out transmission requests, the arbiter selects one of the buffers according to the weightings.

5. The I/O circuit as claimed in claim 1, wherein each buffer further determines a required amount of tokens according to the corresponding weighting and data volume of the data packet, and determines whether the data volume corresponding to the accumulating signal is the largest one, and when the amount of tokens in the token bucket is greater than the required amount of tokens, and the data volume corresponding to the accumulating signal is not the largest one, the buffer outputs the normal transmission request.

6. The I/O circuit as claimed in claim 1, wherein a respective size of each token bucket is determined according to the types of the data packets.

7. The I/O circuit as claimed in claim 1, wherein each token bucket is periodically supplemented with a predetermined amount of tokens within a predetermined period according to the types of the data packets.

8. A data transmission control method, comprising:

determining whether a plurality of buffers have data packets which need to be output;

a plurality of accumulators respectively accumulate a data volume output from each buffer, and output an accumulating signal according to the accumulated data volume, each accumulator corresponding to one from among the plurality of buffers;

each buffer outputs a normal transmission request according to an amount of tokens of a corresponding token bucket and the accumulating signal;

a plurality of timers respectively time waiting period for each buffer after each buffer outputs the normal transmission request, and outputting a time-out transmission request when the waiting period exceeds a predetermined period, each timer corresponding to one from among the plurality of buffers;

an arbiter receives the time-out transmission request and the normal transmission request;

the arbiter selects one of the buffers from all of the time-out transmission requests and the normal transmission requests; and

the selected buffer outputs a data packet.

9. The method as claimed in claim 8, the step that the arbiter selects one of the buffers via the arbiter from all of the time-out transmission requests and the normal transmission requests further comprises:

selecting the buffer corresponding to the time-out transmission request when the arbiter receives at least one time-out transmission request and at least one normal transmission request while the arbiter transmits the data packet.

10. The method as claimed in claim 8, the step that the arbiter selects one of the buffers via the arbiter from all of the time-out transmission requests and the normal transmission requests further comprises:

selecting one of the buffers according to weightings corresponding to different types of data when the arbiter receives the plurality of normal transmission requests, wherein the weightings are stored in a lookup table of a storage module.

11. The method as claimed in claim 8, the step that the arbiter selects one of the buffers via the arbiter from all of the time-out transmission requests and the normal transmission requests further comprises:

selecting one of the buffers according to weightings corresponding to different types of data when the arbiter receives the time-out transmission requests, wherein the weightings are stored in a lookup table of a storage module.

12. The method as claimed in claim 8, further comprising:

determining a required amount of tokens via the buffer according to weightings corresponding to different types of data and the data volume of the data packet, wherein the weightings are stored in a lookup table of a storage module;

determines whether the data volume corresponding to the accumulating signal is the largest one; and

each buffer outputs the normal transmission request when the amount of tokens in the corresponding token bucket is greater than the required amount of tokens, and the data volume corresponding to the accumulating signal is not the largest one.

13. The method as claimed in claim 8, further comprising:

determining a respective size of each token bucket according to the types of the data packets.

14. The method as claimed in claim 8, further comprising:

periodically supplementing with a predetermined amount of tokens within a predetermined period to each token bucket according to the types of the data packets.