Re: [RFC PATCH 0/2] dma: DMA slave device bringup tool

[Vinod Koul <vkoul@kernel.org>]

On 24-02-26, 17:34, Frank Li wrote:
> On Sat, Feb 21, 2026 at 02:22:46PM +0100, Alexander Gordeev wrote:
> > Hi All,
> >
> > This is a custom tool that can be used to bring up DMA slave devices.
> > It consists of a user-level utility and a companion device driver that
> > communicate via IOCTL.
> >
> > The tool is likely need some polishing, but I would like first get some
> > feedback to ensure there is interest.
> >
> > I also tested it only on x86 and have little idea on how channel names
> > on other architectures look like. That could especially impact the way
> > dma_request_channel() treats user-provided target DMA channel names, as
> > exposed via /sys/class/dma.
> 
> I am not sure if it can work for general dma engine because it slave setting
> is tight coupling with FIFO settings and timing, some periphal require
> start dma firstly, then enable DMA. some perphial require enable DMA first
> then queue dma transfer.
> 
> burst len is also related with FIFO 's watermark settings.

Correct!

I like the idea but it is not practical. Every dmaengine is tied to the
peripheral for setting up the transfer. It is not a memcpy! How did you
test it, which controller was used ..?

-- 
~Vinod