From: "Enrico Weigelt, metux IT consult" <enrico.weigelt@gr13.net>
To: Daniel Vetter <daniel@ffwll.ch>
Cc: dri devel <dri-devel@lists.freedesktop.org>
Subject: Re: Frame buffer access performance
Date: Fri, 5 Aug 2016 11:04:21 +0200 [thread overview]
Message-ID: <57A45695.9060804@gr13.net> (raw)
In-Reply-To: <20160805081557.GA6232@phenom.ffwll.local>
On 05.08.2016 10:15, Daniel Vetter wrote:
Hi,
> There's a driver cap DRM_CAP_DUMB_PREFER_SHADOW for this. If set,
> render into a shadow buffer and copy over in bursts, otherwise you
> can assume that the memory is fully cpu cached and fast with random
> access.
aaaah!
nekrad@orion:~/src/linux$ git grep prefer_shadow drivers/gpu/drm/i915
drivers/gpu/drm/i915/intel_display.c: dev->mode_config.prefer_shadow = 1;
IOW: i915 driver (my notebook here has an i915) sets that flag, so
it seems my guess is right.
Do we already have some suitable double-buffer helpers, which can detect
changed regions and copy over in bursts, so userland doesn't
need extra logic for that ? (hmm, maybe some cow + pagefault magic?)
... seems I need to give it some further thoughts ...
--mtx
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel
next prev parent reply other threads:[~2016-08-05 9:04 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-08-05 2:35 Frame buffer access performance Enrico Weigelt, metux IT consult
2016-08-05 8:15 ` Daniel Vetter
2016-08-05 9:04 ` Enrico Weigelt, metux IT consult [this message]
2016-08-05 9:23 ` Daniel Vetter
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=57A45695.9060804@gr13.net \
--to=enrico.weigelt@gr13.net \
--cc=daniel@ffwll.ch \
--cc=dri-devel@lists.freedesktop.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