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From: Maksym Kokhan <maksym.kokhan@globallogic.com>
Date: Thu, 30 Jul 2020 15:17:12 +0300
Message-ID: <CAMT6-xgFCydUT9CFvsKsZf3YMGzGpJD0A=ek+4dU1F=vEif2eA@mail.gmail.com>
Subject: question about work on CMA integration into DMA
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Hello!

I am working on some driver, which needs to allocate a big contiguous
memory block (~10 MB) and has to work on multiple platforms (x86, arm,
arm64, mips, powerpc). CMA - is the most appropriate way in this case,
but I have faced an unexpected problem - the fact that the CMA
subsystem is not integrated into the DMA subsystem for powerpc,
and I cannot request memory from CMA area from my kernel module.
The question is: is there any work in progress on CMA to DMA
integration?  Or is it decided not to perform such work at all?
And, is there any legal way to allocate a big contiguous memory block
from the kernel module on powerpc?

Thanks for your help,
Max