From: Jesse Barnes <jbarnes@virtuousgeek.org>
To: M.K.Edwards@gmail.com
Cc: KyongHo Cho <pullip.cho@samsung.com>,
Russell King - ARM Linux <linux@arm.linux.org.uk>,
Arnd Bergmann <arnd@arndb.de>,
Catalin Marinas <catalin.marinas@arm.com>,
Joerg Roedel <joro@8bytes.org>,
linaro-mm-sig@lists.linaro.org, linux-mm@kvack.org,
Kyungmin Park <kyungmin.park@samsung.com>,
linux-arm-kernel@lists.infradead.org
Subject: Re: [Linaro-mm-sig] [RFC 0/2] ARM: DMA-mapping & IOMMU integration
Date: Mon, 13 Jun 2011 11:54:37 -0700 [thread overview]
Message-ID: <20110613115437.62824f2f@jbarnes-desktop> (raw)
In-Reply-To: <BANLkTi=C6NKT94Fk6Rq6wmhndVixOqC6mg@mail.gmail.com>
On Mon, 13 Jun 2011 10:55:59 -0700
"Michael K. Edwards" <m.k.edwards@gmail.com> wrote:
> As far as I can tell, there is not yet any way to get real
> cache-bypassing write-combining from userland in a mainline kernel,
> for x86/x86_64 or ARM.
Well only if things are really broken. sysfs exposes _wc resource
files to allow userland drivers to map a given PCI BAR using write
combining, if the underlying platform supports it.
Similarly, userland mapping of GEM objects through the GTT are supposed
to be write combined, though I need to verify this (we've had trouble
with it in the past).
--
Jesse Barnes, Intel Open Source Technology Center
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2011-06-13 18:54 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-05-25 7:35 [RFC 0/2] ARM: DMA-mapping & IOMMU integration Marek Szyprowski
2011-05-25 7:35 ` [RFC 1/2] ARM: Move dma related inlines into arm_dma_ops methods Marek Szyprowski
2011-05-25 7:35 ` [RFC 2/2] ARM: initial proof-of-concept IOMMU mapper for DMA-mapping Marek Szyprowski
2011-06-13 14:12 ` [RFC 0/2] ARM: DMA-mapping & IOMMU integration KyongHo Cho
2011-06-13 15:07 ` Arnd Bergmann
2011-06-13 15:30 ` KyongHo Cho
2011-06-13 15:40 ` Catalin Marinas
2011-06-13 16:00 ` [Linaro-mm-sig] " KyongHo Cho
2011-06-13 17:55 ` Michael K. Edwards
2011-06-13 18:54 ` Jesse Barnes [this message]
2011-06-14 18:15 ` Michael K. Edwards
2011-06-14 18:21 ` Jesse Barnes
2011-06-14 19:10 ` Zach Pfeffer
2011-06-14 20:59 ` Michael K. Edwards
2011-06-13 18:01 ` Catalin Marinas
2011-06-13 15:46 ` Arnd Bergmann
2011-06-13 15:58 ` [Linaro-mm-sig] " KyongHo Cho
2011-06-14 7:46 ` Marek Szyprowski
2011-06-20 14:31 ` Subash Patel
2011-06-20 14:59 ` Marek Szyprowski
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=20110613115437.62824f2f@jbarnes-desktop \
--to=jbarnes@virtuousgeek.org \
--cc=M.K.Edwards@gmail.com \
--cc=arnd@arndb.de \
--cc=catalin.marinas@arm.com \
--cc=joro@8bytes.org \
--cc=kyungmin.park@samsung.com \
--cc=linaro-mm-sig@lists.linaro.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-mm@kvack.org \
--cc=linux@arm.linux.org.uk \
--cc=pullip.cho@samsung.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).