Dear community, we already had a similar problem on colibri-imx6 reported here and as suggested from @stefan.tx setting the CMA to 32 in the kernel solves our problem.
Now I try to do the same thing in the kernel 4.9.23.x from the BSP 2.8 but nothing changed on the run time, the CMA is always set to the default of 128MB, even if I pass the argument from u-boot.
In the @stefan.tx last answer it tells that with newer kernels it could be necessary to change the device tree, but I don’t know how. Can you point me to a more detailed documentation or example on how to set the CMA to 32MB value in the kernel 4.9-2.3.x ?
Thank you for your help,
Stefano.