==========
Arm-2D GPU
==========

Arm-2D is not a GPU but **an abstraction layer for 2D GPUs dedicated to
Microcontrollers**. It supports all Cortex-M processors ranging from
Cortex-M0 to the latest Cortex-M85.

Arm-2D is an open-source project on Github. For more, please refer to:
https://github.com/ARM-software/Arm-2D.

How to Use
**********

In general, you can set the macro :c:macro:`LV_USE_GPU_ARM2D` to ``1`` in
``lv_conf.h`` to enable Arm-2D acceleration for LVGL.

If you are using
`CMSIS-Pack <https://github.com/lvgl/lvgl/tree/master/env_support/cmsis-pack>`__
to deploy the LVGL. You don't have to define the macro
:c:macro:`LV_USE_GPU_ARM2D` manually, instead, please select the component
``GPU Arm-2D`` in the **RTE** dialog. This step will define the macro for us.

Design Considerations
*********************

As mentioned before, Arm-2D is an abstraction layer for 2D GPU; hence if
there is no accelerator or dedicated instruction set (such as Helium or
ACI) available for Arm-2D, it provides negligible performance boost for
LVGL (sometimes worse) for regular Cortex-M processors.

**We highly recommend you enable Arm-2D acceleration for LVGL** when:

-  The target processors are **Cortex-M55** and/or **Cortex-M85**
-  The target processors support
   `Helium <https://developer.arm.com/documentation/102102/0103/?lang=en>`__.
-  The device vendor provides an arm-2d compliant driver for their
   propriotory 2D accelerators and/or customized instruction set.
-  The target device contains
   `DMA-350 <https://community.arm.com/arm-community-blogs/b/internet-of-things-blog/posts/arm-corelink-dma-350-next-generation-direct-memory-access-for-endpoint-ai>`__

Examples
********

-  `A Cortex-M55 (supports Helium) based MDK Project, PC emulation is
   available. <https://github.com/lvgl/lv_port_an547_cm55_sim>`__

API
***

:ref:`lv_gpu_arm2d`
