From mboxrd@z Thu Jan 1 00:00:00 1970 From: mike.looijmans@topic.nl (Mike Looijmans) Date: Fri, 8 May 2015 14:17:25 +0200 Subject: dma_alloc_coherent versus streaming DMA, neither works satisfactory In-Reply-To: <20150508111048.GE2067@n2100.arm.linux.org.uk> References: <5538DD02.6050401@topic.nl> <3382997.5hgfVKmNXP@wuerfel> <5540D356.50708@topic.nl> <9622793.RaVBbeJMCx@wuerfel> <554B49F0.1090100@topic.nl> <554B6917.40705@topic.nl> <554B71F6.5000106@topic.nl> <20150507143010.GC2067@n2100.arm.linux.org.uk> <554C4FCE.6070802@topic.nl> <20150508111048.GE2067@n2100.arm.linux.org.uk> Message-ID: <554CA955.4020205@topic.nl> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org ?On 08-05-15 13:10, Russell King - ARM Linux wrote: > Well, I do find the language used rather loose. The term "coherent" is > well understood, but when the documentation mixes it with "consistent" > it becomes less clear whether the two terms mean the same thing or > something different. I re-read https://www.kernel.org/doc/Documentation/DMA-API.txt with this in mind. "Part Ia" starts with "dma_alloc_coherent" and (friends) but then talks about "consistent" memory throughout the whole part. I think a s/consistent/coherent/g in this part will make things a lot clearer for everyone. Shall I submit a patch for that? Part Ib continues, but switches to using the word "coherent" instead. Kind regards, Mike Looijmans System Expert TOPIC Embedded Products Eindhovenseweg 32-C, NL-5683 KH Best Postbus 440, NL-5680 AK Best Telefoon: +31 (0) 499 33 69 79 Telefax: +31 (0) 499 33 69 70 E-mail: mike.looijmans at topicproducts.com Website: www.topicproducts.com Please consider the environment before printing this e-mail