From: Jonathan Marek <jonathan@marek.ca>
To: Rob Clark <robdclark@gmail.com>, Christoph Hellwig <hch@lst.de>,
Jordan Crouse <jcrouse@codeaurora.org>
Cc: freedreno <freedreno@lists.freedesktop.org>,
Sean Paul <sean@poorly.run>, David Airlie <airlied@linux.ie>,
Daniel Vetter <daniel@ffwll.ch>,
"open list:DRM DRIVER FOR MSM ADRENO GPU"
<linux-arm-msm@vger.kernel.org>,
"open list:DRM DRIVER FOR MSM ADRENO GPU"
<dri-devel@lists.freedesktop.org>,
open list <linux-kernel@vger.kernel.org>
Subject: Re: [RESEND PATCH v2 4/5] drm/msm: add DRM_MSM_GEM_SYNC_CACHE for non-coherent cache maintenance
Date: Mon, 16 Nov 2020 12:52:41 -0500 [thread overview]
Message-ID: <b798d954-d0b5-d968-f03c-b3fe9ffd08fc@marek.ca> (raw)
In-Reply-To: <CAF6AEGuFzsurd4n6G-nUmCusTJ8vMo9Kqjzs3JRS_d6n+qHgEA@mail.gmail.com>
On 11/16/20 12:50 PM, Rob Clark wrote:
> On Mon, Nov 16, 2020 at 9:33 AM Christoph Hellwig <hch@lst.de> wrote:
>>
>> On Sat, Nov 14, 2020 at 03:07:20PM -0500, Jonathan Marek wrote:
>>> qcom's vulkan driver has nonCoherentAtomSize=1, and it looks like
>>> dma_sync_single_for_cpu() does deal in some way with the partial cache line
>>> case, although I'm not sure that means we can have a nonCoherentAtomSize=1.
>>
>> No, it doesn't. You need to ensure ownership is managed at
>> dma_get_cache_alignment() granularity.
>
> my guess is nonCoherentAtomSize=1 only works in the case of cache
> coherent buffers
>
nonCoherentAtomSize doesn't apply to coherent memory (as the name
implies), I guess qcom's driver is just wrong about having
nonCoherentAtomSize=1.
Jordan just mentioned there is at least one conformance test for this, I
wonder if it just doesn't test it well enough, or just doesn't test the
non-coherent memory type?
next prev parent reply other threads:[~2020-11-16 17:56 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-14 15:17 [RESEND PATCH v2 0/5] drm/msm: support for host-cached BOs Jonathan Marek
2020-11-14 15:17 ` [RESEND PATCH v2 1/5] drm/msm: add MSM_BO_CACHED_COHERENT Jonathan Marek
2020-11-14 15:17 ` [RESEND PATCH v2 2/5] dma-direct: add dma_direct_bypass() to force direct ops Jonathan Marek
2020-11-14 16:21 ` Christoph Hellwig
2020-11-14 15:17 ` [RESEND PATCH v2 3/5] drm/msm: call dma_direct_bypass() Jonathan Marek
2020-11-14 16:21 ` Christoph Hellwig
2020-11-14 15:17 ` [RESEND PATCH v2 4/5] drm/msm: add DRM_MSM_GEM_SYNC_CACHE for non-coherent cache maintenance Jonathan Marek
2020-11-14 16:24 ` Christoph Hellwig
2020-11-14 18:46 ` Rob Clark
2020-11-14 18:54 ` Jonathan Marek
2020-11-14 19:39 ` Rob Clark
2020-11-14 20:07 ` Jonathan Marek
2020-11-14 20:48 ` Rob Clark
2020-11-16 17:33 ` Christoph Hellwig
2020-11-16 17:50 ` Rob Clark
2020-11-16 17:52 ` Jonathan Marek [this message]
2020-11-29 18:51 ` Rob Clark
2020-11-16 17:27 ` [Freedreno] " Jordan Crouse
2020-11-16 17:25 ` Jordan Crouse
2020-11-14 15:17 ` [RESEND PATCH v2 5/5] drm/msm: bump up the uapi version Jonathan Marek
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=b798d954-d0b5-d968-f03c-b3fe9ffd08fc@marek.ca \
--to=jonathan@marek.ca \
--cc=airlied@linux.ie \
--cc=daniel@ffwll.ch \
--cc=dri-devel@lists.freedesktop.org \
--cc=freedreno@lists.freedesktop.org \
--cc=hch@lst.de \
--cc=jcrouse@codeaurora.org \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=robdclark@gmail.com \
--cc=sean@poorly.run \
/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).