I believe you are using rockchip BSP.
LE runs upstream mainline kernels only (inevitably with some patches, but we try to limit that). LE 11.x uses Linux 6.1, LE 12.x uses Linux 6.6 and LE13 (master/dev) currently usues 6.6, 6.9 or 6.10 depending on the SoC platform. All kernel and ffmpeg sources are in the buildsystem.
BSP kernels are universally horrible and need to die in fire ![]()