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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


  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

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