linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: catalin.marinas@arm.com (Catalin Marinas)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 3/3] swiotlb: Add support for CMA allocations
Date: Fri, 13 Dec 2013 13:37:17 +0000	[thread overview]
Message-ID: <20131213133717.GD22933@arm.com> (raw)
In-Reply-To: <52AA595B.7090708@codeaurora.org>

On Fri, Dec 13, 2013 at 12:48:27AM +0000, Laura Abbott wrote:
> On 12/10/2013 2:42 AM, Catalin Marinas wrote:
> > For coherency, we could build it on top of whatever dma (allocation) ops
> > are registered, whether swiotlb or iommu (see part of
> > https://git.kernel.org/cgit/linux/kernel/git/cmarinas/linux-aarch64.git/commit/?h=devel&id=c67fe405be6b55399c9e53dfeba5e2c6b930e429)
> >
> > Regarding iommu, I don't think we need CMA on top, so it makes sense to
> > keep the CMA in the swiotlb code.
> 
> Catalin, is that just sample/design code or is that patch going to be 
> merged sometime?

I was originally hoping that on ARMv8 systems the DMA will be coherent.
But I got requests (though people claiming that only for development)
for cache coherency, hence the above patch. I would like to merge it at
some point (this form or another). The pending issue is describing
whether a device or bus is coherent or not. So there is some work on
system topology and DT before.

-- 
Catalin

  reply	other threads:[~2013-12-13 13:37 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-12-10  0:12 [PATCH 0/3] CMA support for arm64 Laura Abbott
2013-12-10  0:12 ` [PATCH 1/3] arm64: Check for NULL device before getting the coherent_dma_mask Laura Abbott
2013-12-10  0:12 ` [PATCH 2/3] arm64: Enable CMA Laura Abbott
2013-12-10  0:12 ` [PATCH 3/3] swiotlb: Add support for CMA allocations Laura Abbott
2013-12-10  0:29   ` Konrad Rzeszutek Wilk
2013-12-10  0:36     ` Laura Abbott
2013-12-10  0:40       ` Konrad Rzeszutek Wilk
2013-12-10 10:25         ` Will Deacon
2013-12-10 10:42           ` Catalin Marinas
2013-12-10 13:50             ` Will Deacon
2013-12-10 13:56               ` Konrad Rzeszutek Wilk
2013-12-10 14:50               ` Catalin Marinas
2013-12-10 19:03                 ` Laura Abbott
2013-12-13  0:48             ` Laura Abbott
2013-12-13 13:37               ` Catalin Marinas [this message]
2013-12-13 13:45                 ` Will Deacon

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=20131213133717.GD22933@arm.com \
    --to=catalin.marinas@arm.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    /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).