Hello,

On Sun, 26 Feb 2017 18:14:42 +0100, Johannes Thoma wrote:

As you pointed out the solution would be to allocate the memory earlier in the
boot process, by modifying the driver. I will try that in the next few days and
let you know the result.

The whole point of CMA is that allocating earlier in the boot process
should not be necessary. CMA guarantees that the memory reserved for
the CMA pool is "movable", i.e it can be discarded when a CMA
allocation is done.

So if a CMA allocation fails, I would rather suggest that the size of
your CMA pool is not large enough. Check your Device Tree and/or kernel
command (you can specify the size of the CMA pool on both if I remember
correctly).

Best regarsd,

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com