Die-to-Die Streaming Protocol With Credit-Based Flow Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing data communication systems face issues with network communication reliability due to receivers being overwhelmed by data, leading to dropped data and decreased performance, particularly in systems with high latency and bandwidth variations.
Innovation Solution
Implementing a die-to-die credit-based flow control mechanism that adjusts data transmission based on credit counts, allowing packets to be transmitted only when credits are available, and synchronizing credit returns with clock cycles to manage buffer sizes and bandwidths.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a flow control mechanism is implemented to prevent receiver overload, then data loss is reduced, but transmission latency increases due to buffer management overhead
Solution Approach 1:
The patent implements preliminary action by pre-allocating buffer credits to the receiver before data transmission begins. The receiver receives advance notification of available buffer space through credit signals, allowing the sender to prepare and transmit data immediately without waiting for buffer availability confirmation, thereby reducing transmission latency while maintaining reliable flow control.
2Reliability
If buffer size is increased to accommodate high bandwidth variations, then data overflow is prevented, but system complexity and resource consumption increase
Solution Approach 1:
The patent applies dynamics by implementing a dynamic credit-based flow control mechanism where buffer credits are dynamically allocated, tracked, and returned based on actual buffer availability. The credit count changes dynamically as data is transmitted and buffers are freed, allowing the system to adapt to varying bandwidth conditions without requiring excessively large fixed buffers, thus reducing overall system complexity.
Solution Approach 2:
The patent implements feedback through the credit return mechanism where the receiver continuously monitors buffer availability and sends credit signals back to the sender. This feedback loop allows the sender to adjust transmission rates in real-time based on actual buffer conditions, preventing overflow without requiring complex predetermined buffer sizing, thereby reducing system complexity while maintaining reliability.
3Reliability
If credit-based flow control is implemented for die-to-die interfaces, then network communication reliability is improved, but protocol overhead and processing requirements increase
Solution Approach 1:
The patent applies merging by integrating the credit-based flow control mechanism directly into the die-to-die interface protocol stack, combining buffer management, flow control, and data transmission functions into a unified protocol layer. This integration eliminates the need for separate complex control mechanisms and reduces processing overhead by handling multiple functions through a single coordinated protocol framework.
Data Source
AI summary
Provided are systems, methods, and apparatuses for streaming protocol flow control for die-to-die interfaces. In some examples, the systems, devices, and methods include allowing a first packet to be transmitted from a source to a destination based on a credit count; decrementing the credit count based on transmitting a flit of the first packet to the destination; and incrementing the credit count based on receiving a first return credit from the destination. In some examples, the systems, devices, and methods include receiving, at a destination from a source, a first return credit in a header flit of a first packet; incrementing a credit count based on receiving the first return credit from the source; allowing a second packet to be transmitted to the source based on the credit count; and decrementing the credit count based on transmitting a flit of the second packet to the source.