GPU internal peripheral

Revision as of 11:20, 1 February 2022 by Registered User

Applicable for STM32MP15x lines

1 Article purpose[edit]

The purpose of this article is to:

  • briefly introduce the GPU peripheral and its main features
  • indicate the level of security supported by this hardware block
  • explain how each instance can be allocated to the runtime contexts and linked to the corresponding software components
  • explain, when necessary, how to configure the GPU peripheral.

2 Peripheral overview[edit]

The GPU peripheral is a dedicated graphics processing unit. It accelerates numerous 3D graphics applications such as graphical user interface (GUI), menu display or animations. It works together with an optimized software stack designed for industry-standard APIs and supporting AndroidTM and Linux® embedded development platforms.

2.1 Features[edit]

Refer to the STM32MP15 reference manuals for the complete list of features, and to the software components, introduced below, to see which features are implemented.

2.2 Security support[edit]

The GPU is a non-secure peripheral.

3 Peripheral usage and associated software[edit]

3.1 Boot time[edit]

The GPU is not used at boot time.

3.2 Runtime[edit]

3.2.1 Overview[edit]

The GPU internal peripheral is allocated to the Arm® Cortex®-A7 non-secure core running the Linux® userland.

Chapter Peripheral assignment describes which peripheral instance can be assigned to which context.

3.2.2 Software frameworks[edit]

Domain Peripheral Software components Comment
OP-TEE Linux STM32Cube
Visual GPU OpenGL®ES framework

3.2.3 Peripheral configuration[edit]

The configuration is applied by the firmware running in the context to which the peripheral is assigned. The configuration can be done alone via the STM32CubeMX tool for all internal peripherals, and then manually completed (particularly for external peripherals), according to the information given in the corresponding software framework article, and in the GPU device tree configuration article for Linux®.

3.2.4 Peripheral assignment[edit]

Click on the right to expand the legend...

STM32MP15 internal peripherals

Check boxes illustrate the possible peripheral allocations supported by STM32 MPU Embedded Software:

  • means that the peripheral can be assigned () to the given runtime context.
  • means that the peripheral can be assigned to the given runtime context, but this configuration is not supported in STM32 MPU Embedded Software distribution.
  • is used for system peripherals that cannot be unchecked because they are statically connected in the device.

Refer to How to assign an internal peripheral to an execution context for more information on how to assign peripherals manually or via STM32CubeMX.
The present chapter describes STMicroelectronics recommendations or choice of implementation. Additional possiblities might be described in STM32MP15 reference manuals.

Domain Peripheral Runtime allocation Comment
Instance Cortex-A7
secure
(OP-TEE)
Cortex-A7
non-secure
(Linux)
Cortex-M4

(STM32Cube)
Visual GPU GPU

4 How to go further[edit]

Please go through the articles belonging to the GPU category.

5 References[edit]