From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: adharmap@codeaurora.org, linux-kernel@vger.kernel.org,
linux-arm-msm@vger.kernel.org, dwalker@codeaurora.org,
arnd@arndb.de, akpm@linux-foundation.org, mingo@elte.hu,
joerg.roedel@amd.com, maciej.sosnowski@intel.com,
dan.j.williams@intel.com, beckyb@kernel.crashing.org,
yanghy@cn.fujitsu.com, linux-arch@vger.kernel.org,
adharmap@quicinc.com
Subject: Re: [RFC PATCH] dma: Add barrierless dma mapping/unmapping api
Date: Wed, 27 Jan 2010 17:49:47 +1100 [thread overview]
Message-ID: <1264574987.3601.171.camel@pasglop> (raw)
In-Reply-To: <20100127141901P.fujita.tomonori@lab.ntt.co.jp>
On Wed, 2010-01-27 at 14:19 +0900, FUJITA Tomonori wrote:
> > I somehow missed your post, my apologies. Agreed that
> dma_map/unmap_sg
> > would be the correct api to use here, however they still call the
> > dmac_.*_range to map buffers.
>
> Hmm, sounds like arm's implementation issue. dma_map_sg API doesn't
> require such. dma_map_sg API gives what you want, do a sync only after
> mapping the last buffer.
dmac_* appears to be ARM's low-level ops for cache flushing on
non-coherent DMA, so it's really down to arch stuff here and how ARM
implements dma_[un]map_sg() and we keep a sane global driver API.
Cheers,
Ben.
next prev parent reply other threads:[~2010-01-27 6:51 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-26 2:35 [RFC PATCH] dma: Add barrierless dma mapping/unmapping api adharmap
2010-01-26 4:30 ` Benjamin Herrenschmidt
2010-01-26 4:43 ` FUJITA Tomonori
2010-01-26 20:11 ` Abhijeet Dharmapurikar
2010-01-27 5:19 ` FUJITA Tomonori
2010-01-27 6:49 ` Benjamin Herrenschmidt [this message]
2010-01-26 16:48 ` Randy Dunlap
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=1264574987.3601.171.camel@pasglop \
--to=benh@kernel.crashing.org \
--cc=adharmap@codeaurora.org \
--cc=adharmap@quicinc.com \
--cc=akpm@linux-foundation.org \
--cc=arnd@arndb.de \
--cc=beckyb@kernel.crashing.org \
--cc=dan.j.williams@intel.com \
--cc=dwalker@codeaurora.org \
--cc=fujita.tomonori@lab.ntt.co.jp \
--cc=joerg.roedel@amd.com \
--cc=linux-arch@vger.kernel.org \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=maciej.sosnowski@intel.com \
--cc=mingo@elte.hu \
--cc=yanghy@cn.fujitsu.com \
/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).