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From: Russell King - ARM Linux <linux@arm.linux.org.uk>
To: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	dmaengine@vger.kernel.org, Lars-Peter Clausen <lars@metafoo.de>,
	Vinod Koul <vinod.koul@intel.com>,
	Nicolas Ferre <nicolas.ferre@atmel.com>,
	Christoph Hellwig <hch@lst.de>,
	"James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>,
	Dan Williams <dan.j.williams@intel.com>,
	Sumit Semwal <sumit.semwal@linaro.org>,
	linux-arm-kernel <linux-arm-kernel@lists.infradead.org>
Subject: Re: [Question about DMA] Consistent memory?
Date: Sat, 2 Jan 2016 10:39:48 +0000	[thread overview]
Message-ID: <20160102103948.GR8644@n2100.arm.linux.org.uk> (raw)
In-Reply-To: <CAK7LNASd1amcHinXzYy=8mtYbnHUY1G_v=fthpachAVSyjqPZA@mail.gmail.com>

On Thu, Dec 31, 2015 at 04:50:54PM +0900, Masahiro Yamada wrote:
> Hi.
> 
> I am new to the Linux DMA APIs.
> 
> First, I started by reading Documentation/DMA-API.txt,
> but I am confused with the term "consistent memory".

Just read "coherent memory" instead - the documentation confusingly uses
the two terms to refer to the same thing.  I think there was a patch a
while back to replace "consistent" with "coherent" in this document,
though I'm not sure what happened to it.

I think you have answers to your other points by others in this thread.

Thanks.

-- 
RMK's Patch system: http://www.arm.linux.org.uk/developer/patches/
FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up
according to speedtest.net.

  parent reply	other threads:[~2016-01-02 10:40 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-12-31  7:50 [Question about DMA] Consistent memory? Masahiro Yamada
2015-12-31  8:38 ` Mike Looijmans
2015-12-31 10:25 ` One Thousand Gnomes
2015-12-31 14:57   ` Masahiro Yamada
2015-12-31 17:12     ` Mike Looijmans
2016-01-02 10:53     ` Russell King - ARM Linux
2016-01-02 10:39 ` Russell King - ARM Linux [this message]
2016-01-02 16:17   ` James Bottomley
2016-01-02 18:07     ` Russell King - ARM Linux
2016-01-02 18:35   ` Mike Looijmans
2016-01-02 20:10     ` James Bottomley

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