From: Eric Anholt <eric@anholt.net>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: devel@driverdev.osuosl.org, linux-media@vger.kernel.org,
Mauro Carvalho Chehab <mchehab@kernel.org>,
linux-rpi-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org, Eric Anholt <eric@anholt.net>
Subject: [PATCH 4/6] staging: bcm2835-v4l2: Add a TODO file for improvements we need.
Date: Fri, 27 Jan 2017 13:55:01 -0800 [thread overview]
Message-ID: <20170127215503.13208-5-eric@anholt.net> (raw)
In-Reply-To: <20170127215503.13208-1-eric@anholt.net>
Signed-off-by: Eric Anholt <eric@anholt.net>
---
drivers/staging/media/platform/bcm2835/TODO | 39 +++++++++++++++++++++++++++++
1 file changed, 39 insertions(+)
create mode 100644 drivers/staging/media/platform/bcm2835/TODO
diff --git a/drivers/staging/media/platform/bcm2835/TODO b/drivers/staging/media/platform/bcm2835/TODO
new file mode 100644
index 000000000000..61a509992b9a
--- /dev/null
+++ b/drivers/staging/media/platform/bcm2835/TODO
@@ -0,0 +1,39 @@
+1) Support dma-buf memory management.
+
+In order to zero-copy import camera images into the 3D or display
+pipelines, we need to export our buffers through dma-buf so that the
+vc4 driver can import them. This may involve bringing in the VCSM
+driver (which allows long-term management of regions of memory in the
+space that the VPU reserved and Linux otherwise doesn't have access
+to), or building some new protocol that allows VCSM-style management
+of Linux's CMA memory.
+
+2) Avoid extra copies for padding of images.
+
+We expose V4L2_PIX_FMT_* formats that have a specified stride/height
+padding in the V4L2 spec, but that padding doesn't match what the
+hardware can do. If we exposed the native padding requirements
+through the V4L2 "multiplanar" formats, the firmware would have one
+less copy it needed to do.
+
+3) Port to ARM64
+
+The bulk_receive() does some manual cache flushing that are 32-bit ARM
+only, which we should convert to proper cross-platform APIs.
+
+4) Convert to be a platform driver.
+
+Right now when the module probes, it tries to initialize VCHI and
+errors out if it wasn't ready yet. If bcm2835-v4l2 was built in, then
+VCHI generally isn't ready because it depends on both the firmware and
+mailbox drivers having already loaded.
+
+We should have VCHI create a platform device once it's initialized,
+and have this driver bind to it, so that we automatically load the
+v4l2 module after VCHI loads.
+
+5) Drop the gstreamer workaround.
+
+This was a temporary workaround for a bug that was fixed mid-2014, and
+we should remove it before stabilizing the driver.
+
--
2.11.0
next prev parent reply other threads:[~2017-01-27 21:55 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-01-27 21:54 [PATCH 0/6] staging: BCM2835 MMAL V4L2 camera driver Eric Anholt
2017-01-27 21:54 ` [PATCH 1/6] staging: Import the BCM2835 MMAL-based " Eric Anholt
2017-02-03 18:59 ` Mauro Carvalho Chehab
2017-02-05 22:15 ` Dave Stevenson
2017-02-05 23:13 ` Michael Zoran
2017-02-06 8:30 ` Greg Kroah-Hartman
2017-02-06 12:37 ` Mauro Carvalho Chehab
2017-02-06 15:01 ` Dave Stevenson
2017-02-06 9:08 ` Hans Verkuil
2017-02-06 11:37 ` Dave Stevenson
2017-02-06 12:58 ` Hans Verkuil
2017-02-06 15:21 ` Dave Stevenson
2017-02-06 16:00 ` Hans Verkuil
2017-02-10 9:47 ` Hans Verkuil
2017-02-06 12:59 ` Hans Verkuil
2017-01-27 21:54 ` [PATCH 2/6] staging: bcm2835-v4l2: Update the driver to the current VCHI API Eric Anholt
2017-01-27 21:55 ` [PATCH 3/6] staging: bcm2835-v4l2: Add a build system for the module Eric Anholt
2017-01-29 14:12 ` Michael Zoran
2017-02-03 19:01 ` Mauro Carvalho Chehab
2017-01-27 21:55 ` Eric Anholt [this message]
2017-01-27 21:55 ` [PATCH 5/6] staging: bcm2835-v4l2: Apply many whitespace fixes from checkpatch Eric Anholt
2017-01-27 21:55 ` [PATCH 6/6] staging: bcm2835-v4l2: Apply spelling " Eric Anholt
2017-01-27 22:30 ` Joe Perches
2017-01-30 20:05 ` Eric Anholt
2017-01-31 1:38 ` Joe Perches
2017-01-31 18:30 ` Eric Anholt
2017-01-31 18:49 ` Joe Perches
2017-03-15 14:01 ` [PATCH 0/6] staging: BCM2835 MMAL V4L2 camera driver Mauro Carvalho Chehab
2017-03-15 21:50 ` Stefan Wahren
2017-03-15 22:01 ` Eric Anholt
2017-03-16 1:08 ` Mauro Carvalho Chehab
2017-03-16 1:46 ` Michael Zoran
2017-03-16 9:29 ` Mauro Carvalho Chehab
2017-03-18 0:34 ` Eric Anholt
2017-03-19 16:58 ` Mauro Carvalho Chehab
2017-03-19 17:04 ` Michael Zoran
2017-03-20 1:11 ` Mauro Carvalho Chehab
2017-03-20 10:58 ` Mauro Carvalho Chehab
2017-03-20 11:08 ` Michael Zoran
2017-03-20 14:58 ` Mauro Carvalho Chehab
2017-03-20 15:11 ` Michael Zoran
2017-03-20 15:33 ` Mauro Carvalho Chehab
2017-03-20 15:40 ` Michael Zoran
2017-03-20 11:57 ` Stefan Wahren
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=20170127215503.13208-5-eric@anholt.net \
--to=eric@anholt.net \
--cc=devel@driverdev.osuosl.org \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-media@vger.kernel.org \
--cc=linux-rpi-kernel@lists.infradead.org \
--cc=mchehab@kernel.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).