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From: Clifford Wolf <clifford@clifford•at>
To: linuxppc-embedded@ozlabs•org
Subject: Re: Mem-2-Mem DMA - Generalized API
Date: Wed, 4 Jul 2007 11:05:54 +0200	[thread overview]
Message-ID: <20070704090554.GA30693@clifford.at> (raw)
In-Reply-To: <20070625180110.GH20463@clifford.at>

Hi,

On Mon, Jun 25, 2007 at 08:01:10PM +0200, Clifford Wolf wrote:
> I've put a 'draft header file' of an api as I would have expected it
> online: [...]

Ok, so here comes the first implementation:
(I also have other projects, so it took a while.. ;-)

	http://www.clifford.at/priv/dmatransfer-20070704.diff

This is just for the MPC8349 DMA now, registers are still hardcoded in the
driver instead of beeing taken from the platform files and support for
scatter-gather is still missing and the Kconfig integration isn't checking
if we are building for the mpc8349 (or even ppc) yet. But I think the
direction of the API is pretty clear.

The patch also contains a hackish demo client (dma_demo_client.ko) which is
performing some dma transfers in the 256th MB of physical memory. So it
should only be used on a machine with 256MB of memory bootet with mem=255M
(but changing that should be trivial). The demo client shows well how the
API works and how much overhead the API adds.

Any feedback this time?

yours,
 - clifford

-- 
#!/usr/bin/perl
$p="1"x1002;for$c(2..1000){if($p=~/^.{$c}0/){next;};printf"%3d\%s",
$c,++$x%14?" ":"\n";while($p=~s/^((.{$c})+)1/${1}0/){}}$_="lPSFZQ".
"SJNFTZBUZ<IUUQ:;;XXX.DMJGGPSE.BU;QSJNF;>\n";y:B-Zl;:a-x M/:;print;

  parent reply	other threads:[~2007-07-04  9:02 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-06-24 19:39 Mem-2-Mem DMA - Generalized API Clifford Wolf
2007-06-24 20:21 ` Arnd Bergmann
2007-06-25  8:03   ` Clifford Wolf
2007-06-25 11:03   ` Matt Sealey
2007-06-25 12:53     ` Clemens Koller
2007-06-25 14:31       ` Matt Sealey
2007-06-25 17:00         ` Olof Johansson
2007-06-25 17:48           ` Clifford Wolf
2007-06-25 18:01         ` Clifford Wolf
2007-06-25 21:20           ` Matt Sealey
2007-07-04  9:05           ` Clifford Wolf [this message]
2007-07-04 10:11             ` Clemens Koller
2007-07-07  5:24             ` Timur Tabi
2007-07-07  8:41               ` Clifford Wolf
2007-07-07 13:08             ` Arnd Bergmann
2007-07-07 13:27               ` Clifford Wolf
2007-07-07 13:28                 ` Arnd Bergmann
2007-07-07 13:34               ` Clifford Wolf
2007-07-11  9:35               ` Clifford Wolf

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