Critical Workload Check

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.

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.