dmaengine.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Peter Ujfalusi <peter.ujfalusi@ti.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>,
	Andy Shevchenko <andy.shevchenko@gmail.com>,
	Vinod Koul <vkoul@kernel.org>,
	dmaengine <dmaengine@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Dan Williams <dan.j.williams@intel.com>,
	Linux-sh list <linux-sh@vger.kernel.org>,
	Linux-Renesas <linux-renesas-soc@vger.kernel.org>
Subject: Re: [PATCH 0/3] dmaengine: Stear users towards dma_request_slave_chan()
Date: Tue, 4 Feb 2020 09:01:55 +0100	[thread overview]
Message-ID: <CAMuHMdUYcSPoK8NOSdMzU_Jtg84aPMNKeGnacnF7=aidV4eqvw@mail.gmail.com> (raw)
In-Reply-To: <b09ad222-f5b8-af5a-6c2b-2dd6b30f1c73@ti.com>

Hi Peter,

On Tue, Feb 4, 2020 at 7:52 AM Peter Ujfalusi <peter.ujfalusi@ti.com> wrote:
> On 03/02/2020 22.34, Geert Uytterhoeven wrote:
> > On Mon, Feb 3, 2020 at 9:21 PM John Paul Adrian Glaubitz
> > <glaubitz@physik.fu-berlin.de> wrote:
> >> On 2/3/20 2:32 PM, Geert Uytterhoeven wrote:
> >>> Both rspi and sh-msiof have users on legacy SH (i.e. without DT):
> >>
> >> FWIW, there is a patch set by Yoshinori Sato to add device tree support
> >> for classical SuperH hardware. It was never merged, unfortunately :(.
> >
> > True.
> >
> >>> Anyone who cares for DMA on SuperH?
> >>
> >> What is DMA used for on SuperH? Wouldn't dropping it cut support for
> >> essential hardware features?
> >
> > It may make a few things slower.
>
> I would not drop DMA support but I would suggest to add dma_slave_map
> for non DT boot so the _compat() can be dropped.

Which is similar in spirit to gpiod_lookup and clk_register_clkdev(),
right?

> Imho on lower spec SoC (and I believe SuperH is) the DMA makes big
> difference offloading data movement from the CPU.

Assumed it is actually used...

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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

  reply	other threads:[~2020-02-04  8:02 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-03 10:18 [PATCH 0/3] dmaengine: Stear users towards dma_request_slave_chan() Peter Ujfalusi
2020-02-03 10:18 ` [PATCH 1/3] dmaengine: Remove unused define for dma_request_slave_channel_reason() Peter Ujfalusi
2020-02-03 13:35   ` Geert Uytterhoeven
2020-02-03 10:18 ` [PATCH 2/3] dmaengine: Mark dma_request_slave_channel() deprecated Peter Ujfalusi
2020-02-03 10:18 ` [PATCH 3/3] dmaengine: Encourage dma_request_slave_channel_compat() users to migrate Peter Ujfalusi
2020-02-03 10:35   ` Andy Shevchenko
2020-02-03 10:37 ` [PATCH 0/3] dmaengine: Stear users towards dma_request_slave_chan() Andy Shevchenko
2020-02-03 10:59   ` Peter Ujfalusi
2020-02-03 11:16     ` Andy Shevchenko
2020-02-03 12:09       ` Peter Ujfalusi
2020-02-03 12:48         ` Andy Shevchenko
2020-02-03 13:32         ` Geert Uytterhoeven
2020-02-03 20:21           ` John Paul Adrian Glaubitz
2020-02-03 20:34             ` Geert Uytterhoeven
2020-02-03 21:26               ` John Paul Adrian Glaubitz
2020-02-04  8:13                 ` Geert Uytterhoeven
2020-02-04  6:52               ` Peter Ujfalusi
2020-02-04  8:01                 ` Geert Uytterhoeven [this message]
2020-02-04  8:15                   ` Peter Ujfalusi
2020-02-04  8:21                     ` Peter Ujfalusi
2020-02-04  9:16                   ` Rob Landley
2020-02-04  9:27                     ` Geert Uytterhoeven
2020-02-04 10:18                       ` Rob Landley
2020-02-04  6:21   ` Vinod Koul
2020-02-04 11:21     ` Andy Shevchenko
2020-02-05  4:43       ` Vinod Koul
2020-02-05  8:10         ` Peter Ujfalusi
2020-02-05 11:31           ` Vinod Koul
2020-02-05 11:56             ` Peter Ujfalusi
2020-02-05 11:59               ` Vinod Koul

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='CAMuHMdUYcSPoK8NOSdMzU_Jtg84aPMNKeGnacnF7=aidV4eqvw@mail.gmail.com' \
    --to=geert@linux-m68k.org \
    --cc=andy.shevchenko@gmail.com \
    --cc=dan.j.williams@intel.com \
    --cc=dmaengine@vger.kernel.org \
    --cc=glaubitz@physik.fu-berlin.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-renesas-soc@vger.kernel.org \
    --cc=linux-sh@vger.kernel.org \
    --cc=peter.ujfalusi@ti.com \
    --cc=vkoul@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).