Debug graphics issues - Qualcomm Dragonwing Documentation

You can use the Snapdragon Profiler and kernel commands for performance profiling of the applications. This section describes how to collect information for profiling and debugging using the kernel commands, and how to collect logs. Caution Use these commands with caution because they may impact the power consumption of the device.

Capture Weston/Wayland logs

You can use the Wayland/Weston logs to verify whether the display driver is loaded on the device and to find the supported OpenGL ES extensions. To capture the Weston/Wayland debug logs, run the following command before launching the Weston or any other application:

export WAYLAND_DEBUG=server/client

Debug Kernel/KGSL

You can evaluate the performance of your application by adjusting the GPU to different frequency levels and setting the GPU or CPU to performance mode. Based on these evaluations, you can optimize the performance of your application.

Set CPU to performance mode

Remount the file system using the following command:
mount -o remount,rw /

To set all CPU cores, replace cpux with cpu0, cpu1, and cpun.

echo 1 > /sys/devices/system/cpu/[cpux]/online

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors

Sample output ondemand userspace performance schedutil

If any CPU clock is running at a low frequency, set the CPU to performance mode and verify the issue by running the following command:
echo performance > /sys/devices/system/cpu/[cpux]/cpufreq/scaling_governor

To validate the trial settings, run the following commands:

cat /sys/devices/system/cpu/[cpux]/online (cpux : cpu0,cpu1 …)

cat /sys/devices/system/cpu/[cpux]/cpufreq/scaling_governor(cpux : cpu0, cpu1 …)

Set GPU frequency

Note The following commands work only with the Adreno/KGSL overlay or the qcom‑multimedia‑proprietary‑image.

Remount the file system using the following command:
mount -o remount,rw /
For the power level, check the available_frequencies sys node.
cat /sys/class/kgsl/kgsl-3d0/devfreq/available_frequencies
Sample output 812000000 700000000 608000000 550000000 450000000 315000000 From the sample output, you can interpret GPU power levels as:
Frequency 812000000 700000000 608000000 550000000 450000000 315000000
Power level 0 1 2 3 4 5
Increment the GPU power level by one and perform the GPU power-level test by substituting <level> with 0, 1, 2, 3, 4, and 5 in the following commands:
echo <level> > /sys/class/kgsl/kgsl-3d0/min_pwrlevel
echo <level> > /sys/class/kgsl/kgsl-3d0/max_pwrlevel

Frequency	812000000	700000000	608000000	550000000	450000000	315000000
Power level	0	1	2	3	4	5

Note For QCS5430:

The Adreno GPU frequency is fixed at 315 MHz.
The power levels specified here aren’t supported and the output of the available_frequencies command displays 315000000.

Set GPU to performance mode

To set the GPU to performance mode, run the following command:
mount -o remount,rw / echo 0 > /sys/class/kgsl/kgsl-3d0/min_pwrlevel echo 0 > /sys/class/kgsl/kgsl-3d0/max_pwrlevel
Note These commands force the GPU to always run at the maximum frequency.
To ensure that the GPU doesn’t enter the low-power state even if the device is idle for 10000000 ms, run the following command:
mount -o remount,rw / echo 10000000 > /sys/class/kgsl/kgsl-3d0/idle_timer

To set the GPU to performance mode while ensuring that the GPU doesn’t enter the low-power state, run the following command:

mount -o remount,rw /
echo 0 > /sys/class/kgsl/kgsl-3d0/min_pwrlevel
echo 0 > /sys/class/kgsl/kgsl-3d0/max_pwrlevel
echo 10000000 > /sys/class/kgsl/kgsl-3d0/idle_timer

Note QCS5430 doesn’t support performance mode because the Adreno GPU frequency is fixed at 315 MHz.

Check other KGSL settings

To enable the KGSL clock, run the following command:
echo 1 > /sys/class/kgsl/kgsl-3d0/force_clk_on
To enable the KGSL rail, run the following command:
echo 1 > /sys/class/kgsl/kgsl-3d0/force_rail_on
To enable the KGSL bus, run the following command:
echo 1 > /sys/class/kgsl/kgsl-3d0/force_bus_on

Debug OpenGL ES-based applications

You can use the Snapdragon Profiler tool to capture snapshots and real-time traces of OpenGL ES applications. For more information, see Snapdragon Profiler.

Debug OpenCL-based applications

You can use the Snapdragon Profiler tool to capture snapshots and real-time traces of OpenCL applications.

For more information, see Snapdragon Profiler.
For performance profiling, see Performance profiling in Qualcomm® Snapdragon™ Mobile Platform OpenCL General Programming and Optimization Guide.

Note Some sections in the Qualcomm® Snapdragon™ Mobile Platform OpenCL General Programming and Optimization Guide apply to Android platforms but not to Qualcomm Linux devices. However, some profiling options are purely based on the OpenCL API and are therefore supported on the Qualcomm Linux devices. For example, the clGetEventProfilingInfo API.

Debug Vulkan-based applications

Use the Snapdragon Profiler tool to capture snapshots and real-time traces of Vulkan applications. For more information, see Snapdragon Profiler. Also, you can use validation layers to debug Vulkan applications.

Debug Vulkan application using validation layers

To debug a Vulkan application using validation layers, do the following on the Linux host computer:

To set the source environment, run the following command:

source <path-to-installed-platform-eSDK>/environment-setup-armv8-2a-qcom-linux

To download the validation layers, run the following command:

git clone https://github.com/KhronosGroup/Vulkan-ValidationLayers

To build the validation layers, run the following commands:

cd Vulkan-ValidationLayers
cmake -S . -B build -D UPDATE_DEPS=ON -D BUILD_WSI_XLIB_SUPPORT=OFF -D BUILD_TESTS=OFF -D CMAKE_BUILD_TYPE=Release -D BUILD_WSI_XCB_SUPPORT=OFF -D BUILD_WSI_WAYLAND_SUPPORT=ON
cmake --build build --config Debug

scp -r build/layers/libVkLayer_khronos_validation.so root@[IP-address-of-the-device]:/tmp/local/debug/vulkan/

scp -r build/layers/VkLayer_khronos_validation.json root@[IP-address-of-the-device]:/tmp/local/debug/vulkan/

export VK_LAYER_PATH=/tmp/local/debug/vulkan:$VK_LAYER_PATH

Note If the /tmp/local/debug/vulkan directory isn’t available, create a similar directory.

To enable the validation layers on Vulkan applications, set the VK_INSTANCE_LAYERS environment variable as follows:
export VK_INSTANCE_LAYERS=VK_LAYER_KHRONOS_validation

To edit or append the settings in the layers/vk_layer_settings.txt file, run the following command:

khronos_validation.debug_action = VK_DBG_LAYER_ACTION_LOG_MSG
khronos_validation.report_flags = error,warn,perf
khronos_validation.file = true
khronos_validation.log_filename = vk_validatedump.txt

To push the layers/vk_layer_settings.txt file to the device, run the following command:

scp -r vk_layer_settings.txt root@[IP-address-of-the-device]:/tmp/local/debug/vulkan/

To dump the log, add path of the validation layers by running the following command:
export VK_LAYER_SETTINGS_PATH=/tmp/local/debug/vulkan/vk_layer_settings.txt
This command generates the dumps in the same directory where the Vulkan application binary exists.

Note If you are facing issues compiling the application or running it, use the following commands to check out the specific version. Later, repeat the steps from 3 to 7 and recompile the application and run.

git checkout -b <local_branch_name> --track remotes/origin/vulkan-sdk-1.3.275

example: git checkout -b 13275 --track remotes/origin/vulkan-sdk-1.3.275

To avoid data flush in the tmp directory, save the Vulkan application binary to another location. If you change the location of the binary, ensure that you update the environment variables and verify the changes after rebooting.

​Capture Weston/Wayland logs

​Debug Kernel/KGSL

​Set CPU to performance mode

​Set GPU frequency

​Set GPU to performance mode

​Check other KGSL settings

​Debug OpenGL ES-based applications

​Debug OpenCL-based applications

​Debug Vulkan-based applications

​Debug Vulkan application using validation layers