Acceleration of 1x1 convolutions in convolutional neural networks

A system, comprising:

• a stream engine, which, in operation, streams feature and kernel data;
• and
• a convolutional accelerator coupled to the stream engine, wherein the convolutional accelerator, in operation, receives streams of feature and kernel data from the stream engine, the convolutional accelerator including:
• a feature line buffer;
• a kernel buffer;
• a multiply-accumulate cluster coupled to the feature line buffer and the kernel buffer;
• and
• mode control circuitry coupled to the feature line buffer, the kernel buffer and the MAC cluster, wherein the mode control circuitry:
• in a first mode of operation of the convolutional accelerator:
• stores feature data in the feature line buffer;
• stores kernel data in the kernel buffer;
• transfers feature data from the feature line buffer to the MAC cluster;
• and
• transfers kernel data from the kernel buffer to the MAC cluster;
• and
• in a second mode of operation of the convolutional accelerator:
• stores feature data in the kernel buffer;
• stores kernel data in the feature line buffer;
• transfers feature data from the kernel buffer to the MAC cluster;
• and
• transfers kernel data from the feature line buffer to the MAC cluster.

A method, comprising:

• streaming feature data and kernel data to a convolutional accelerator;
• and
• convolving streamed kernel data with streamed feature data, the convolving including:
• in a first mode of operation of the convolutional accelerator:
• storing feature data in a feature line buffer of the convolutional accelerator;
• storing kernel data in a kernel buffer of the convolutional accelerator;
• transferring feature data from the feature line buffer to a MAC cluster of the convolutional accelerator;
• and
• transferring kernel data from the kernel buffer to the MAC cluster;
• and
• in a second mode of operation of the convolutional accelerator:
• storing feature data in the kernel buffer;
• storing kernel data in the feature line buffer;
• transferring feature data from the kernel buffer to the MAC cluster;
• and
• transferring kernel data from the feature line buffer to the MAC cluster.

A non-transitory computer-readable medium having contents which configure a convolutional accelerator having a plurality of modes of operation to convolve streamed kernel data with streamed feature data, the convolving including:

• in a first mode of operation of the plurality of modes of operation of the convolutional accelerator:
• storing feature data in a feature line buffer of the convolutional accelerator;
• storing kernel data in a kernel buffer of the convolutional accelerator;
• transferring feature data from the feature line buffer to a MAC cluster of the convolutional accelerator;
• and
• transferring kernel data from the kernel buffer to the MAC cluster;
• and
• in a second mode of operation of the plurality of modes of operation of the convolutional accelerator:
• storing feature data in the kernel buffer;
• storing kernel data in the feature line buffer;
• transferring feature data from the kernel buffer to the MAC cluster;
• and
• transferring kernel data from the feature line buffer to the MAC cluster.