[PATCH RFC] davinci: da850: define edma-memcpy-channels

Sekhar Nori nsekhar at ti.com
Sun Sep 10 23:22:28 PDT 2017

Hi Adam,

On Saturday 09 September 2017 05:58 PM, Adam Ford wrote:
> When booting with a device tree, message appears:
>    memcpy is disabled
> When reading through the bindings for eDMA3, it shows that
> ti,edma-memcpy-channels is an optional property, but the example
> binding uses it.
> RFC:  I'll be the first to admit that I don't understand what
> this is doing, but it seems like a DMA enabled memcpy would
> improve performance.  Is this appropriate for da850?  Since there
> are two eDMA3-tpcc controllers, is there a set of channels we can
> use for each?
> Signed-off-by: Adam Ford <aford173 at gmail.com>

This enables DMA-based memcpy (see drivers/dma/dmaetest.c for example).
But does not accelerate any memcpy in kernel automatically.

If this is done, it should be done in a board specific manner because
the available channels you pick up for memcpy support can change from
board to board.


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