Technology for controlling access to processor debug features
US11734457B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 23, 2019 |
| Grant date | Aug 22, 2023 |
| Priority date | — |
| Expiry date | Dec 20, 2041 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F21/79
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A processor that was manufactured by a manufacturer comprises privileged debug operational circuitry, a debug restriction fuse, a credential store, a credential of the manufacturer in the credential store, and debug control circuitry. The debug restriction fuse is a one-time programmable fuse. The debug control circuitry is to automatically restrict access to the privileged debug operational circuitry, based on the debug restriction fuse. The processor may also include public debug operational circuitry, a prevent-unauthorized-debug (PUD) fuse, and an undo-PUD fuse. When the PUD fuse is set and the undo-PUD fuse is clear, the debug control circuitry may respond to an attempt by a debugger to use the public debug operational circuitry by determining whether the debugger is authorized, disallowing access if the debugger is not authorized, and allowing access if the debugger is authorized. Other embodiments are described and claimed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.