Global Debug Controller Tag RAM Trace Filtering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current debugging techniques for data processors face inefficiencies in filtering and managing data trace information across multiple debug clients, leading to unnecessary data collection and processing of irrelevant trace information.
Innovation Solution
A system employing a global debug controller with a tag Random Access Memory (RAM) that filters data trace information using a common filtering criteria, where a tag bit associated with each address determines whether to maintain or discard data trace information, reducing unnecessary data collection and processing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a trace window is used to indicate an address range for capturing trace information, then trace information can be captured, but the trace window must be sufficiently large to include all address locations where data of interest is stored, resulting in capture of unnecessary trace information
Solution Approach 1:
The patent divides the trace information filtering into multiple stages: first a coarse filter using trace windows to capture potentially relevant information, then finer filtering using tag RAM and filter logic to separate useful from unnecessary data. This segmentation allows the system to start with broad capture and progressively refine to precise selection.
Solution Approach 2:
The patent implements preliminary filtering actions by pre-configuring tag RAM with address masks and filter criteria before trace information arrives. The tag RAM is pre-loaded with patterns that identify which address ranges are of interest, enabling rapid filtering of incoming trace data without requiring post-capture analysis.
2Device complexity
If multiple debug clients share a common trace buffer, then data collection is centralized, but unnecessary data from multiple clients is processed and transmitted
Solution Approach 1:
The patent applies filtering criteria and tag RAM configurations in advance, before trace information is collected and stored. Each debug client's trace window and filter parameters are pre-configured to match their specific debugging needs, so that when trace data flows through the common buffer, the filtering logic is already in place to immediately separate relevant from irrelevant information.
Solution Approach 2:
The patent extracts only the necessary trace information from the common buffer by using tag RAM to identify and isolate relevant data patterns. The filter logic continuously monitors incoming trace data and extracts only those portions that match the pre-configured criteria for each debug client, discarding unnecessary data before it consumes buffer space or processing resources.
3Reliability
If trace information is captured for all address locations within a trace window, then complete coverage is achieved, but data processing and transmission volume increases
Solution Approach 1:
The patent pre-configures the tag RAM with address masks that define the precise patterns of interest within each trace window. These masks are loaded before debugging sessions begin, establishing the filtering criteria in advance. When trace information arrives, the pre-configured masks enable immediate pattern matching and selective capture, eliminating the need for post-capture filtering and reducing processing time while maintaining completeness of relevant data.
Data Source
AI summary
In a processing system comprising a plurality of data processors at an integrated circuit die, each data processor has a local debug module. In response to acquiring data trace information based upon a corresponding local filtering criteria, the local debug modules transmit their data trace information to a global resource from each of the local debug modules for further filtering by a common filtering criteria.