# US 2021/0279835 A1 · Critical Workload Check > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0279835 A1 - Document ID: US20210279835A1 - Status: Published application - Kind: A1 - Application number: 17/187,844 - Filed: 2021-02-28 - Published: 2021-09-09 - Earliest claimed: 2020-02-28 - Assignees: Imagination Technologies Limited - Applicants: Imagination Technologies Limited - Inventors: Mario Sopena Novales; Philip Morris - Web page: https://patentgrep.com/patent/US20210279835A1 ## CPC - G06T 1/20: Processor architectures; Processor configuration, e.g. pipelining - G06F 9/44505: {Configuring for program initiating, e.g. using registry, configuration files} - G06F 11/0751: {Error or fault detection not based on redundancy (power supply failures G06F1/30; network fault management H04L41/06)} - G06F 11/0793: {Remedial or corrective actions (recovery from an exception in an instruction pipeline G06F9/3861; by retry G06F11/1402; for recovering from a failure of a protocol instance or entity H04L69/40)} - G06F 11/1417: {Boot up procedures} - G06F 11/3024: {where the computing system component is a central processing unit [CPU]} - G06T 1/60: Memory management - G06F 11/1004: {to protect a block of data words, e.g. CRC or checksum (G06F11/1076 takes precedence; security arrangements for protecting computers or computer systems against unauthorized activity G06F21/00)} - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract A method of initialising rendering at a graphics processing unit configured to perform safety-critical rendering, the method comprising: causing an instruction for initialising rendering of safety critical graphical data at the graphics processing unit to be provided to the graphics processing unit, said instruction comprising a request for response from the graphics processing unit; initialising a timer, said timer being configured to expire after a time period; and monitoring, during said time period, for a response from the graphics processing unit; determining, by a safety controller external to the graphics processing unit, that an initialisation error has occurred if no response is received from the graphics processing unit before the timer expires. ## Claims ### Claim 1 A method of initialising rendering at a graphics processing unit configured to perform safety-critical rendering, the method comprising: causing an instruction for initialising rendering of safety critical graphical data at the graphics processing unit to be provided to the graphics processing unit, said instruction comprising a request for a response from the graphics processing unit; initialising a timer, said timer being configured to expire after a time period; and monitoring, during said time period, for the response from the graphics processing unit; determining, by a safety controller external to the graphics processing unit, that an initialisation error has occurred if no response is received from the graphics processing unit before the timer expires. ### Claim 2 (depends on 1) The method as claimed in claim 1, wherein the safety controller causes the graphics processing unit to be reset in response to determining that the initialisation error has occurred. ### Claim 3 (depends on 1) The method as claimed in claim 1, wherein the method further comprises: proceeding with rendering of safety critical graphical data at the graphics processing unit if the response from the graphics processing unit is received by the safety controller. ### Claim 4 (depends on 1) The method as claimed in claim 1, wherein the time period is determined in dependence on the safety critical graphical data to be rendered. ### Claim 5 A graphics processing system comprising a graphics processing unit configured to perform safety-critical rendering and a safety controller for the graphics processing system, the safety controller being external to the graphics processing unit, in which the safety controller is configured to: cause an instruction for initialising rendering of safety critical graphical data at the graphics processing unit to be provided to the graphics processing unit, said instruction comprising a request for a response from the graphics processing unit; initialise a timer, said timer being configured to expire after a time period; and monitor, during said time period, for the response from the graphics processing unit; and determine that an initialisation error has occurred if no response is received from the graphics processing unit before the timer expires. ### Claim 6 (depends on 5) The graphics processing system as claimed in claim 5, wherein the safety controller causes the graphics processing unit to be reset in response to determining that the initialisation error has occurred. ### Claim 7 (depends on 5) The graphics processing system as claimed in claim 5, wherein the graphics processing unit is configured to: proceed with rendering of safety critical graphical data if the response from the graphics processing unit is received by the safety controller. ### Claim 8 (depends on 5) The graphics processing system as claimed in claim 5, wherein the time period is determined in dependence on the safety critical graphical data to be rendered. ### Claim 9 A method of initialising rendering at a graphics processing unit configured to perform safety-critical rendering, the method comprising: generating configuration data for initialising rendering of safety critical graphical data at the graphics processing unit; causing an instruction comprising the configuration data for initialising rendering and a request for a response from the graphics processing unit to be provided to the graphics processing unit; initialising a timer, said timer being configured to expire after a time period; monitoring, during the time period, for the response from the graphics processing unit; configuring the graphics processing unit in accordance with the configuration data for initialising rendering; determining whether the graphics processing unit is correctly configured in accordance with the configuration data, the instruction requesting that the graphics processing unit respond on completing said determining; and determining, by a safety controller external to the graphics processing unit, that an initialisation error has occurred if: (i) it is determined that the graphics processing unit is not correctly configured in accordance with the configuration data; or (ii) no response is received from the graphics processing unit before the timer expires. ### Claim 10 (depends on 9) The method as claimed in claim 9, wherein the safety controller causes the graphics processing unit to be reset in response to determining that the initialisation error has occurred. ### Claim 11 (depends on 9) The method as claimed in claim 9, wherein the method further comprises proceeding with rendering of safety critical graphical data at the graphics processing unit if: (i) it is determined that the graphics processing unit is correctly configured in accordance with the configuration data; and (ii) the response from the graphics processing unit is received by the safety controller. ### Claim 12 (depends on 9) The method as claimed in claim 9, wherein the configuration data comprises one or more register entries to be written into one or more registers of the graphics processing unit, said configuration data specifying a configuration to be adopted by the graphics processing unit. ### Claim 13 (depends on 9) The method as claimed in claim 9, wherein the configuring of the graphics processing unit in accordance with the configuration data comprises one of: the safety controller writing the one or more register entries into the one or more registers; or a firmware of the graphics processing unit writing the one or more register entries into the one or more registers. ### Claim 14 (depends on 12) The method as claimed in claim 12, wherein determining whether the graphics processing unit has been correctly configured in accordance with the configuration data comprises: reading the one or more register entries corresponding to the configuration data back from each of the one or more registers of the graphics processing unit after configuring the graphics processing unit; and comparing the one or more register entries read back from each register with an expected data entry for that register specified by the configuration data. ### Claim 15 (depends on 12) The method as claimed in claim 12, wherein determining whether the graphics processing unit has been correctly configured in accordance with the configuration data comprises: reading the one or more register entries corresponding to the configuration data back from each of the one or more registers of the graphics processing unit after configuring the graphics processing unit; performing a checksum over the one or more register entries read back from the one or more registers; performing a checksum over the configuration data; and comparing the results of said checksums. ### Claim 16 (depends on 15) The method as claimed in claim 15, wherein the checksum is dependent upon the location of the one or more register entries within the one or more registers.