[FAQ] TDA4VH-Q1: Steps to Duplicate and Register a New C7x Kernel

1. Duplicate the Kernel Folder

• Copy the folder: vision_apps/apps/basic_demos/app_c7x_kernel
• 
  Rename the copied folder with your new kernel name, e.g.: app_c7x_kernel_cp

2. Update Build Output Paths

Modify the output paths in the following .mak files to match your new kernel name :

• vision_apps/apps/basic_demos/app_c7x_kernel_cp/c7x/concerto.mak

• vision_apps/apps/basic_demos/app_c7x_kernel_cp/concerto.mak

3. Add Output Library Path

Depending on the build target, update the following files:

• For PC Emulation (x86_64):
  Add your new output library path to: vision_apps/apps/concerto_x86_64_inc.mak

• For Target Build (RTOS on EVM):
  Add your output library path to: vision_apps/platform/<evm>/rtos/concerto_c7x_inc.mak

4. Register and Unregister the Kernel

Update function names and definitions in both host and target code:

• Host File    : vision_apps/apps/basic_demos/app_c7x_kernel_cp/app_c7x_kernel_img_add.c
• Target File : vision_apps/apps/basic_demos/app_c7x_kernel_cp/c7x/app_c7x_target_kernel_img_add.cpp

Update the following functions with your new kernel name:

• Host registration
  • vx_status app_c7x_kernel_img_add_register(vx_context context);
  • vx_status app_c7x_kernel_img_add_unregister(vx_context context);

• Target registration
  • void app_c7x_target_kernel_img_add_register(void);
  • vx_status app_c7x_target_kernel_img_add_unregister(void);

Rename all instances appropriately (e.g., if your kernel is img_sub, change to app_c7x_kernel_img_sub_register, etc.).

Update kernel Name from : /vision_apps/apps/basic_demos/app_c7x_kernel_cp/app_c7x_kernel.h

Change the names of kernel functions in app_c7x_target_kernel_<name>_register and in their function definitions.

5. Hook Kernel into Application Init

In the following file: vision_apps/platform/j784s4/rtos/common/app_init.c

Locate the following functions and add calls to your new register/unregister functions:

• appRegisterOpenVXTargetKernels()

add app_c7x_target_kernel_<your_kernel>_register()

• appUnRegisterOpenVXTargetKernels()

app_c7x_target_kernel_<your_kernel>_unregister();

Replace <your_kernel> with your new kernel identifier.

Notes:

• File renaming is not shown in this summary — make sure to rename .c/.cpp/.h files to match your new kernel name if needed.
• Be consistent with naming across all files, functions, and build paths.