Re: dma_declare_coherent_memory and SuperH

From: Geert Uytterhoeven
Date: Mon Jun 28 2021 - 15:13:17 EST

Hi Christoph,

On Mon, Jun 28, 2021 at 6:33 PM Christoph Hellwig <hch@xxxxxx> wrote:
> On Mon, Jun 28, 2021 at 09:29:59AM -0500, Rob Landley wrote:
> > > No. My hope is to kill dma_declarare_coherent, an API for board
> > > support files to declare device-specific regions to be used for
> > > coherent DMA.
> >
> > Q) If I haven't got regression test hardware to make sure I properly converted
> > each of these entire boards to device tree, Is there anything else I can do to
> > help you remove this function from common code, such as inlining some portion of
> > this function?
> >
> > A) You can convert the board to device tree.
> >
> > Which part of this exchange have I misunderstood?
> The part that there is no easy way out without the device tree
> conversion.

So you keep this functionality around with DT. Which means there's
some code to parse the DT, extract a region, and handle it?
I'm just wondering which terrible maintenance burden would be left by
making the handling function public, so the SH platform code can still call it?



Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds