hello AldoG,
As I mentioned earlier, we are using Linux version 5.15.52. However, I couldn't find the exact kernel version for the Real-Time (RT) Patch. So, we applied the patch for version 5.15.54, which I have attached since versions 5.15.52, 5.15.53, and 5.15.54 were not available.
I successfully added the patch to my kernel, except for two files in the kernel source. I manually added these two files, but they were not included in the patch due to a line mismatch.
It's important to mention that in this patch, CONFIG_PREEMPT_RT is not enabled, but CONFIG_PREEMPT is enabled. after that we enable Fully Preemptible Kernel (CONFIG_PREEMPT_RT)