3.6.1. Introduction

J721E device is enabled with 3D graphics accelerator based on the Rogue 8XE series from Imagination Technologies Inc. It enables the support of 3D graphics rendering using OpenGL® ES API’s. The OpenGL® ES API’s up to and including version 3.2 with render surfaces upto 4k and input textures upto 8k sizes are supported by the hardware.

The following extensions are supported:

Table 3.1 EGL client extensions
EGL_EXT_client_extensions
EGL_EXT_platform_base
EGL_KHR_client_get_all_proc_addresses
EGL_KHR_debug
EGL_EXT_platform_wayland
EGL_MESA_platform_gbm
Table 3.2 EGL extensions
EGL_ANDROID_native_fence_sync
EGL_EXT_buffer_age
EGL_EXT_create_context_robustness
EGL_EXT_image_dma_buf_import
EGL_EXT_image_dma_buf_import_modifiers
EGL_IMG_context_priority
EGL_KHR_config_attribs
EGL_KHR_create_context
EGL_KHR_fence_sync
EGL_KHR_get_all_proc_addresses
EGL_KHR_gl_renderbuffer_image
EGL_KHR_gl_texture_2D_image
EGL_KHR_gl_texture_cubmap_image
EGL_KHR_image
EGL_KHR_image_base
EGL_KHR_image_pixmap
EGL_KHR_no_config_context
EGL_KHR_reusable_sync
EGL_KHR_surfaceless_context
EGL_KHR_wait_sync
EGL_MESA_configless_context
EGL_MESA_drm_image
EGL_MESA_image_dma_buf_export
EGL_WL_bind_wayland_display
EGL_IMG_cl_image
Table 3.3 GL extensions
GL_ANDROID_extension_pack_es31a
GL_EXT_blend_minmax
GL_EXT_buffer_storage
GL_EXT_clip_control
GL_EXT_color_buffer_float
GL_EXT_conservative_depth
GL_EXT_copy_image
GL_EXT_discard_framebuffer
GL_EXT_draw_buffers
GL_EXT_draw_buffers_indexed
GL_EXT_draw_elements_base_vertex
GL_EXT_EGL_image_array
GL_EXT_float_blend
GL_EXT_geometry_point_size
GL_EXT_geometry_shader
GL_EXT_gpu_shader5
GL_EXT_memory_object
GL_EXT_multisampled_render_to_texture
GL_EXT_multisampled_render_to_texture2
GL_EXT_occlusion_query_boolean
GL_EXT_polygon_offset_clamp
GL_EXT_primitive_bounding_box
GL_EXT_pvrtc_sRGB
GL_EXT_read_format_bgra
GL_EXT_robustness
GL_EXT_separate_shader_objects
GL_EXT_shader_framebuffer_fetch
GL_EXT_shader_group_vote
GL_EXT_shader_implicit_conversions
GL_EXT_shader_io_blocks
GL_EXT_shader_non_constant_global_initializers
GL_EXT_shader_pixel_local_storage
GL_EXT_shader_pixel_local_storage2
GL_EXT_shader_texture_lod
GL_EXT_shadow_samplers
GL_EXT_sparse_texture
GL_EXT_sRGB_write_control
GL_EXT_tessellation_point_size
GL_EXT_tessellation_shader
GL_EXT_texture_border_clamp
GL_EXT_texture_buffer
GL_EXT_texture_cube_map_array
GL_EXT_texture_filter_anisotropic
GL_EXT_texture_format_BGRA8888
GL_EXT_texture_rg
GL_EXT_texture_sRGB_decode
GL_EXT_texture_sRGB_R8
GL_EXT_texture_sRGB_RG8
GL_EXT_YUV_target
GL_IMG_bindless_texture
GL_IMG_framebuffer_downsample
GL_IMG_multisampled_render_to_texture
GL_IMG_program_binary
GL_IMG_texture_compression_pvrtc
GL_IMG_texture_compression_pvrtc2
GL_IMG_texture_filter_cubic
GL_IMG_texture_format_BGRA8888
GL_IMG_texture_npot
GL_KHR_blend_equation_advanced
GL_KHR_blend_equation_advanced_coherent
GL_KHR_debug
GL_KHR_robustness
GL_KHR_texture_compression_astc_ldr
GL_KHR_compressed_ETC1_RGB8_texutre
GL_OES_depth24
GL_OES_depth_texture
GL_OES_draw_buffers_indexed
GL_OES_draw_elements_base_vertex
GL_OES_EGL_image_external_essl3
GL_OES_EGL_sync
GL_OES_element_index_uint
GL_OES_fragment_precision_high
GL_OES_geometry_point_size
GL_OES_geometry_shader
GL_OES_get_program_binary
GL_OES_gpu_shader5
GL_OES_mapbuffer
GL_OES_packed_depth_stencil
GL_OES_required_internalformat
GL_OES_rgb8_rgba8
GL_OES_sample_shading
GL_OES_sample_variables
GL_OES_shader_image_atomic
GL_OES_shader_io_blocks
GL_OES_shader_multisample_interpolation
GL_OES_standard_derivatives
GL_OES_surfaceless_context
GL_OES_tessellation_point_size
GL_OES_tessellation_shader
GL_OES_texture_border_clamp
GL_OES_texture_buffer
GL_OES_texture_cube_map_array
GL_OES_texture_float
GL_OES_texture_half_float
GL_OES_texture_npot
GL_OES_texture_stencil8
GL_OES_texture_storage_multisample_2d_array
GL_OES_vertex_array_object
GL_OES_vertex_half_float

For more information about the supported OpenGL® ES and EGL® extensions see:

The OpenGL® ES and EGL® libraries are packaged with the Processor SDK Linux J721e and are used by graphics stacks such as Wayland/Weston. The drivers run on an ARM core and programs the firmware running inside a GPU core with rendering commands submitted by the user applications.

System Message: ERROR/3 (/jenkins/psdkla-dunfell/release/j7-evm-rt/yocto/tisdk/psdkla-builder/psdk-doc-jacinto-fork/source/linux/Foundational_Components/Graphics/Graphics_and_Display.rst, line 534)

Exception occured in ifconfig expression: File "<string>", line 2 Other features of the Rogue series of GPUs include bilinear and trilinear filtering. ^ SyntaxError: invalid syntax

Support for up to 4Kx4K render surfaces.

The rest of this page will cover the following topics:

  • Software architecture of Graphics
  • Instructions on how to run graphics demos
  • Instructions on how to run DSS application
  • Instructions on how launch Weston
  • Instructions on how to run PVR tools

3.6.2. Software Architecture

The picture below shows the software architecture of Graphics in Processor SDK Linux J721e.

../../../_images/rogue-graphics-software-stack.png

Fig. 3.4 PSDK Linux Rogue Graphics Software Stack

Please note that RGX-KM in this context refers to the pvrsrvkm kernel module, which is currently provided at: https://git.ti.com/cgit/graphics/ti-img-rogue-driver

This is included by default in the SDK. The kernel module is located at:

target # /lib/modules/$(uname -r)/extra/pvrsrvkm.ko

It is loaded automatically by the rc.pvr init script in /etc/init.d/ .

3.6.3. Graphics Demos

Along with the graphics driver and userspace libraries, the SDK also includes example applications. Some of the demos are based on the IMG Native_SDK examples.

The following demos are available to run under the Wayland windowing system.

target # /usr/bin/SGX/demos/Wayland/OpenGLESDeferredShading
target # /usr/bin/SGX/demos/Wayland/OpenGLESGaussianBlur
target # /usr/bin/SGX/demos/Wayland/OpenGLESImageBasedLighting
target # /usr/bin/SGX/demos/Wayland/OpenGLESIntroducingPVRCamera
target # /usr/bin/SGX/demos/Wayland/OpenGLESIntroducingPVRUtils
target # /usr/bin/SGX/demos/Wayland/OpenGLESIntroducingUIRenderer
target # /usr/bin/SGX/demos/Wayland/OpenGLESNavigation2D
target # /usr/bin/SGX/demos/Wayland/OpenGLESNavigation3D
target # /usr/bin/SGX/demos/Wayland/OpenGLESParticleSystem

Additionally demos using the Null Window System / KMS / DRM / EGLFS are provided with Qt. By default EGLFS will use the eglfs_kms backend.

target # /usr/share/qt5/examples/opengl/hellogles3/hellogles3 -platform eglfs
target # /usr/share/qt5/examples/opengl/2dpainting/2dpainting -platform eglfs
target # /usr/share/qt5/examples/opengl/paintedwindow/paintedwindow -platform eglfs

The default eglfs_kms configuration file for Qt5 is located at:

target # /etc/qt5/eglfs_kms_cfg.json

For more information about Qt’s EGLFS and using Qt5 in embedded applications see:

3.6.4. Display

TI SoC’s are equipped with Display SubSystem (DSS) hardware to provide hardware acceleration for alpha blending of overlays and color conversion. The DSS hardware is exposed to the software drm API available through libdrm module. Through this drm interface, a user space program can perform mode setting of the display.

The drm module models the display hardware as a series of abstract hardware blocks and manages them through the API. The blocks are:

  • CRTC[1]: represents a scanout engine that generates video timing signal from the data pointed to by the scanout buffer
  • Connector: represents where the video timing signal is sent across to the display
  • Encoder: transforms the video timing signal from CRTC to a format that is suitable for sending across the connector
  • Plane: represents the overlay buffer that a CRTC can be fed with

A utility application modetest can be used to get the list of available drm blocks. All the information available for the device can be displayed by using it.

3.6.4.1. Finding Connector ID

Run the below modetest command:

target # modetest -M tidss -c

Look for the display device for which the connector ID is required - such as HDMI, LCD etc.

Connectors:
id      encoder status          type    size (mm)       modes   encoders
4       3       connected       HDMI-A  480x270         20      3
  modes:
        name refresh (Hz) hdisp hss hse htot vdisp vss vse vtot)
  1920x1080 60 1920 2008 2052 2200 1080 1084 1089 1125 flags: phsync, pvsync; type: preferred, driver
...
16      15      connected       unknown 0x0             1       15
  modes:
        name refresh (Hz) hdisp hss hse htot vdisp vss vse vtot)
  800x480 60 800 1010 1040 1056 480 502 515 525 flags: nhsync, nvsync; type: preferred, driver

The modes displayed are the various resolutions supported by the connected display.

3.6.4.2. Finding Plane ID

To find the Plane ID, run the modetest command:

target # modetest -M tidss -p

which should show something like below:

Planes:
id      crtc    fb      CRTC x,y        x,y     gamma size
19      0       0       0,0             0,0     0
 formats: RG16 RX12 XR12 RA12 AR12 XR15 AR15 RG24 RX24 XR24 RA24 AR24 NV12 YUYV UYVY
 props:
 ...
20      0       0       0,0             0,0     0
 formats: RG16 RX12 XR12 RA12 AR12 XR15 AR15 RG24 RX24 XR24 RA24 AR24 NV12 YUYV UYVY
 props:
 ...

3.6.5. Wayland/Weston

The supported Wayland/Weston version brings in the multiple display support in extended desktop mode and the ability to drag-and-drop windows from one display to the other.

To launch Weston, do the following:

On the target console:

target # unset WAYLAND_DISPLAY

On the default display:

target # weston --tty=1 --display=<default connector-id>

On the secondary display:

target # weston --tty=1 --display=<secondary connector-id>

On all connected displays (LCD and HDMI):

target # weston --tty=1

By default, the screensaver timeout is configured to 300 seconds. The user can change the screensaver timeout using a command line option:

--idle-time=<number of seconds>

For example, to set timeout of 10 minutes and Weston configured to display on all connectors, use the below command:

weston --tty=1 --idle-time=600

To disable the screen timeout and to configure Weston to display on all connectors, use the below command:

weston --tty=1 --idle-time=0

If you face any issues with the above procedure, please refer GLSDK_FAQs#Unable_to_run_Weston_on_the_GLSDK_release for troubling shooting tips.

The filesystem comes with a preconfigured weston.ini file which will be located in

/etc/weston.ini

3.6.5.1. Running Weston clients

Weston client examples can run from the command line on a serial port console or an SSH console. After launching Weston, the user should be able to use the keyboard and the mouse for various controls.
# /usr/bin/weston-flower
# /usr/bin/weston-clickdot
# /usr/bin/weston-cliptest
# /usr/bin/weston-dnd
# /usr/bin/weston-editor
# /usr/bin/weston-eventdemo
# /usr/bin/weston-image /usr/share/weston/terminal.png
# /usr/bin/weston-resizor
# /usr/bin/weston-simple-egl
# /usr/bin/weston-simple-shm
# /usr/bin/weston-simple-touch
# /usr/bin/weston-smoke
# /usr/bin/weston-info
# /usr/bin/weston-terminal

3.6.5.2. Running multimedia with Wayland sink

The GStreamer video sink for Wayland is the waylandsink. To use this video-sink for video playback:

target # gst-launch-1.0 playbin uri=file://<path-to-file-name> video-sink=waylandsink

3.6.5.3. Exiting Weston

Terminate all Weston clients before exiting Weston. If you have invoked Weston from the serial console, exit Weston by pressing Ctrl-C.

If Weston was started automatically by the init system then it can be stopped with:

target # /etc/init.d/weston stop

It is also possible to invoke Weston from the native console, exit Weston by pressing Ctrl-Alt-Backspace.

3.6.5.4. Using IVI shell feature

The SDK also has support for configuring Weston ivi-shell. The default shell that is configured in the SDK is the desktop-shell.

To change the shell to ivi-shell, the user will have to add the following lines into the /etc/weston.ini.

To switch back to the desktop-shell can be done by commenting these lines in the /etc/weston.ini (comments begin with a ‘#’ at the start of line).

[core]
shell=ivi-shell.so

After the above configuration is completed, we can restart Weston by running the following commands

target# /etc/init.d/weston stop
target# /etc/init.d/weston start

Note

When Weston starts with ivi-shell, the default background is black, this is different from the desktop-shell that brings up a window with background.

With ivi-shell configured for Weston, Wayland client applications use ivi-application protocol to be managed by a central HMI window management.

Applications must support the ivi_application Wayland protocol to be managed by the HMI central controller with an unique numeric ID.

Some important references to Weston IVI-shell can be found at the following link:

3.6.5.4.1. Running QT applications with IVI shell

To run the QT application with ivi-shell, set the QT_WAYLAND_SHELL_INTEGRATION environment variable to ivi-shell.

export QT\_WAYLAND\_SHELL\_INTEGRATION=ivi-shell

3.6.6. Using the PowerVR Tools

The suite of PowerVR Tools is designed to enable rapid graphics application development. It targets a range of areas including asset exporting and optimization, PC emulation, prototyping environments, on-line and off-line performance analysis tools and many more. Please refer to PowerVR-SDK for additional details on the tools and detailed documentation.

The target file system includes a subset of PowerVR tools such as PVRScope and PVRTrace recorder libraries from Imagination PowerVR SDK to profile and trace GFX activities. In addition, it also includes PVRPerfServerDeveloper tool.

Note

If you are experiencing issues with any of the tools try updating to the latest provided by Imagination at https://developer.imaginationtech.com/

3.6.6.1. PVRTune

The PVRTune utility is a real-time GPU performance analysis tool. It captures hardware timing data and counters which facilitate the identification of performance bottlenecks. PVRPerfServerDeveloper should be used along with the PVRTune running on the PC to gather data on the SGX loading and activity threads. You can invoke the tool with the below command:

target # /opt/img-powervr-sdk/PVRHub/PVRPerfServer/PVRPerfServerDeveloper

3.6.6.2. PVRTrace

The PVRTrace is an OpenGL® ES API recording and analysis utility. PVRTrace GUI provides off-line tools to inspect captured data, identify redundant calls, highlight costly shaders and many more. The default filesystem contains helper scripts to obtain the PVRTrace of the graphics application. This trace can then be played back on the PC using the PVRTrace Utility.

To start tracing, use the below commands as reference:

target # cp /opt/img-powervr-sdk/PVRHub/Scripts/start_tracing.sh ~/.
target # ./start_tracing.sh <log-filename> <application-to-be-traced>

Example:

target # ./start_tracing.sh westonapp weston-simple-egl

The above command will do the following:

  1. Setup the required environment for the tracing
  2. Create a directory under the current working directory called pvrtrace
  3. Launch the application specified by the user
  4. Start tracing the PVR Interactions while recording the traces to a file under the current directory

To end the tracing, the user can invoke the Ctrl-C and the trace file path will be displayed.

The trace file can then be transferred to a PC, and we can visualize the application using the host side PVRTrace utility. Please refer PowerVR-SDK for more details.

[1]CRTC stands for cathode-ray tube controller, a throw back to the old cathode-ray tubes TV’s which had a controller that generated video timings based on the data it is being fed by a buffer.