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From: Rob Landley <rob@landley.net>
To: Christoph Hellwig <hch@lst.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>,
	Rich Felker <dalias@libc.org>,
	linux-sh@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: dma_declare_coherent_memory and SuperH
Date: Mon, 28 Jun 2021 14:47:15 -0500	[thread overview]
Message-ID: <4415e2cf-5a6a-8e83-a6d8-391c25e1f041@landley.net> (raw)
In-Reply-To: <20210628163312.GA29659@lst.de>

On 6/28/21 11:33 AM, Christoph Hellwig wrote:
> On Mon, Jun 28, 2021 at 09:29:59AM -0500, Rob Landley wrote:
> >> Your plan is to eliminate the ability for non-device-tree boards to do DMA?
>
>> > No.
>
>> Which part of this exchange have I misunderstood?
> 
> The part that there is no easy way out without the device tree
> conversion.

Interesting use of the word "No".

I didn't ask for easy, I asked what needed to be done. What is the patch you
want to apply to kernel/dma so I can see what infrastructure needs to be moved
into arch/sh so it's our problem and not yours.

If a wrapper function has to fake up a temporary device tree snippet to lie to
new DMA infrastructure that refuses to export non-systemd APIs to handle this,
fine. It's still less intrusive than converting EVERY device to a new API on
boards I can't easily regression test. (And hey, if you squint that would be a
little like a partial incremental device tree conversion.)

Rob

  parent reply	other threads:[~2021-06-28 19:30 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-23 13:32 dma_declare_coherent_memory and SuperH Christoph Hellwig
2021-06-23 13:35 ` Geert Uytterhoeven
2021-06-23 13:36 ` John Paul Adrian Glaubitz
2021-06-26 22:36 ` Rob Landley
2021-06-28 13:38   ` Christoph Hellwig
2021-06-28 14:04     ` Rob Landley
2021-06-28 13:49       ` Christoph Hellwig
2021-06-28 14:29         ` Rob Landley
2021-06-28 16:33           ` Christoph Hellwig
2021-06-28 19:12             ` Geert Uytterhoeven
2021-06-28 19:47             ` Rob Landley [this message]
2021-06-27  3:08 ` Daniel Palmer
2021-06-27  8:33   ` John Paul Adrian Glaubitz
2021-06-28  8:57     ` Geert Uytterhoeven
2021-06-28  9:29       ` Daniel Palmer
2021-06-28 10:00         ` Geert Uytterhoeven
2021-06-28 14:29 ` Geert Uytterhoeven
2021-06-28 16:29   ` Christoph Hellwig

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