3D graphics prepare for safety-critical driver graphics
Automotive applications such as digital dashboards, dials, clusters, cockpit domain controllers, surround-view displays, and advanced driver-assistance systems (ADAS) can function with an added layer of protection due to the OpenGL SC (Safety-Critical) 2.0 driver development for Imagination Technologies’ automotive graphics processing units (GPUs).
The company has demonstrated a dashboard with safety-critical elements running on existing automotive silicon.
Designing a vehicle to ISO 26262 encompasses all the hardware and software, from the tooling framework vendors and the operating systems, to the application programming interfaces (APIs) and hardware drivers.
In today’s cars, 3D pixels are widely used in dials, clusters and cameras to display, for example, a surround view. While GPUs have been part of functionally safe domain controllers, no GPU has yet been designed to be functionally safe itself, says Imagination. Safety-critical parts (e.g. speedometer dials, fuel-level indicator, and warning lights for ADAS), have been handled by the CPU which are less capable of 3D graphics.
Imagination has created the building blocks required to create functionally safe graphics systems. Later this year, it will announce fully functionally safe ASIL B- compliant GPUs, designed to protect against permanent and transient fault.
In preparation for this, it has released a safety-critical GPU software driver, the
OpenGL SC 2.0 API software driver development, running on an automotive-grade silicon platform featuring an Imagination GPU. The driver is a clean development, aligned to ISO26262:2018 process requirements.
OpenGL SC is a safety-critical subset of OpenGL ES 2.0. The Safety-Critical Profile for OpenGL ES 2.0 is designed to be deterministic and testable, and omit calls that could potentially return ambiguous, and therefore, unsafe, results.
Porting the demo application from OpenGL ES 2.0 to OpenGL SC was straightforward and achieved in only a couple of days, reports Imagination. Safety-critical code runs with Imagination’s PowerVR Tune debugging tool running in the background, just as it would be done with code written using conventional OpenGL ES, before 3D wireframes appear behind the textured dials.
Imagination Technologies is working with the application framework companies, such as Rightware and Candera and OS companies, such as Greenhills and QNX.
The next steps will be using safety-critical GPUs to run compute applications for ADAS. The company is in the process of enabling more industry-standard automotive safety-critical compute APIs, by working with partners and industry bodies, such as Khronos.
The Khronos OpenGL SC 2.0 specification defines a “safety-critical” subset of OpenGL ES 2.0 for markets requiring highly dependable, safety-related systems, as required by avionics and automotive displays. One goal of using an API that is streamlined for safety-related applications is significantly reduced safety assurance costs.
The OpenGL SC 2.0 driver is based on a published Khronos specification and is expected to pass the Khronos Conformance Process when available. The OpenGL SC driver has been developed in-house at Imagination. It can be fully virtualised by leveraging Imagination’s HyperLane Technology enabling it to be used alongside standard non-safety critical OpenGL ES, Vulkan and OpenCL drivers from Imagination. The combined solution provides access to the full range of automotive APIs.
