How to debug the Gcnano GPU with VTK

1. VTK overview

The VTK (Vivante software ToolKit) is a set of tools :

Tool name	Description	execution plateform
vEmulator	graphics and OpenCL emulator	PC
vProfiler	Embedded tracer for performance profiling (generate log files to feed vAnalyzer)	SoC
vAnalyzer	Visual anlyser for performance profiling (based on logs generated by vProfiler)	PC
vShader	standalone environnement for prototyping and optimizing shader programs	PC
vCompiler	standalone environnement for compiling shader code	PC
vTexture	image transfer utility for image compression/decompression	PC
vTracer	Embedded recorder of OpenGL ES API traces (generate trace files to feed vPlayer)	SoC
vPlayer	Tool to playback recorded API traces files (based on logs generated by vProfiler)	SoC or PC

All these tools are provided in the Vivante SW deliveries.

To have full details about VTK, please refer to the Vivante Software Tool Kit User guide.

1.1. vEmulator

Not tested.

1.2. vProfiler and vAnalyzer

These tools assist software developers in optimizing application performance on Vivante enabled platforms.

1.2.1. vProfiler

During runtime, vProfiler gathers data from performance counters included :

• in GPU
• in SW drivers
• in hardware access layer.

It can track data for a range of frames or a single frame from any application.
These performance metrics are stored in a file (default filename is vprofiler.vpd)

vProfiler activation

• Reload galcore driver with gpuProfiler=1

rmmod galcore.ko
insmod /lib/modules/4.x.x/galcore.ko gpuProfiler=1

• set the following environnement variable

export VIV_PROFILE=1

This will allow basic tracing.

In order to fine tune the configuration of the tracing method, other values are possible for VIV_PROFILE and other environnement variables can be set, as described in the table below :

Env variable	Description
VIV_PROFILE	0 - Disable vProfiler (default) 1 - Enable vProfiler 2 - Control via application call 3 - Allows control over which frames to profile with vProfiler
VP_OUTPUT	Specify the output file name of vProfiler (default is vprofiler.vpd)
VP_FRAME_NUM	When VIV_PROFILE=1, specify the number of frames dumped by vProfiler
VP_FRAME_START	When VIV_PROFILE=3, specify the frame to start profiling with vProfiler
VP_FRAME_END	When VIV_PROFILE=3, specify the frame to end profiling with vProfiler
VP_SYNC_MODE	0 - Disable the synchronous mode of vProfiler 1 - Enable the synchronous mode of vProfiler (default)
VP_USE_GLFINISH	0 - Disable the use of glFinish() instead of eglSwapBuffers() as the frame delimiter (default) 1 - Disable the use of glFinish() instead of eglSwapBuffers() as the frame delimiter

1.2.2. vAnalyzer

This GUI-based tool will allow to open the file generated by the vProfile (.vpd file), and provide a visual analysis of performance results based on :

• customizable charts of performance counters (counters are listed in Appendix A of the Vivante Tool Kit User Guide)
• OpenGL function call statistics
• shader programs statistics (Vertex shader & Pixel shader).

1.3. vShader

Not tested..

1.4. vCompiler

Not tested..

1.5. vTexture

Not tested..

1.6. vTracer and vPlayer

1.6.1. vTracer

Here are some tips but it is not running properly

vTracer setup :

• libraries addition :

cp /media/sdcard/libGLES_vlogger19.so /usr/lib/
cp /media/sdcard/libGLES_vtracer19.so /usr/lib/
cp /media/sdcard/vtracer.conf .

These libraries are provided in the Vivante SW deliveries : vTracer.zip/bin/xxx/
2 trace modes are suppported : Intercept trace mode & Direct Trace mode. (cf Vivante doc for details)

• activation of the traces in Intercept Trace mode

export LD_PRELOAD=/usr/lib/libGLES_vtracer19.so

• deactivation of the traces in Intercept Trace mode

export LD_PRELOAD=

• activation of the traces in Direct Trace mode

export VIV_TRACE=2

• configuration of the tracer

Optionnaly, configuration parameters can be set in the vtracer.conf file

• tracer execution

Trace file will be generated as soon as application is launched (trace_xxx_yyy.bin)

1.6.2. vPlayer

Here are some tips but it is not running properly

vPlayer will allow playback of recorded file from vTracer.
The vPlayer application is capable of running trace files created on another platform

vPLayer setup :

• installation from : vTracer.zip/bin/windows/vplayer_install.zip/setup.exe

• execution :

vplayer [options] tracefilename 

(cf Vivante doc for options details)

Open Computing Language (See http://www.opencl.org/ for more details)

Open Graphics Library (See http://www.opengl.org/ for more details)

Application programming interface

Graphics Processing Units

Graphical User Interface