From: <atull@opensource.altera.com>
To: gregkh@linuxfoundation.org
Cc: Moritz Fischer <moritz.fischer@ettus.com>,
Josh Cartwright <joshc@ni.com>,
monstr@monstr.eu, michal.simek@xilinx.com,
Rob Herring <robh+dt@kernel.org>, Pawel Moll <pawel.moll@arm.com>,
Mark Rutland <mark.rutland@arm.com>,
Ian Campbell <ijc+devicetree@hellion.org.uk>,
Kumar Gala <galak@codeaurora.org>,
Jonathan Corbet <corbet@lwn.net>,
linux-kernel@vger.kernel.org, devicetree@vger.kernel.org,
linux-doc@vger.kernel.org, pantelis.antoniou@konsulko.com,
delicious.quinoa@gmail.com, dinguyen@opensource.altera.com,
Alan Tull <atull@opensource.altera.com>
Subject: [PATCH v12 1/6] fpga: add usage documentation for simple fpga bus
Date: Tue, 27 Oct 2015 17:09:10 -0500 [thread overview]
Message-ID: <1445983755-24007-2-git-send-email-atull@opensource.altera.com> (raw)
In-Reply-To: <1445983755-24007-1-git-send-email-atull@opensource.altera.com>
From: Alan Tull <atull@opensource.altera.com>
Add a document spelling out usage of the simple fpga bus.
Signed-off-by: Alan Tull <atull@opensource.altera.com>
---
v9: Initial version of this patch in patchset
v10: s/fpga/FPGA/g
improve formatting
some rewriting
move to staging/simple-fpga-bus
v11: No change in this patch for v11 of the patch set
v12: Moved out of staging
Small changes due to using FPGA bridge framework and not
representing the bridges as resets.
---
Documentation/fpga/simple-fpga-bus.txt | 58 ++++++++++++++++++++++++++++++++
1 file changed, 58 insertions(+)
create mode 100644 Documentation/fpga/simple-fpga-bus.txt
diff --git a/Documentation/fpga/simple-fpga-bus.txt b/Documentation/fpga/simple-fpga-bus.txt
new file mode 100644
index 0000000..bd43478
--- /dev/null
+++ b/Documentation/fpga/simple-fpga-bus.txt
@@ -0,0 +1,58 @@
+Simple FPGA Bus
+
+Alan Tull 2015
+
+Overview
+========
+
+The simple FPGA bus adds device tree overlay support for FPGA's. Loading a
+DT overlay will result in the FPGA getting an image loaded, its bridges will
+be released, and the DT populated for nodes below the simple-fpga-bus. This
+results in drivers getting probed for the hardware that just got added. This
+is intended to support the FPGA usage where the FPGA has hardware that
+requires drivers. Removing the overlay will result in the drivers getting
+removed and the bridges being disabled.
+
+The simple FPGA bus will need to disable and enable bridges that will only
+affect the child devices that are below the bus. If partial reconfiguration
+is to be done, then bridges will need to be added within the FPGA design to
+protect the rest of the bus when one part of the FPGA design is being
+reconfigured.
+
+
+Sequence
+========
+
+Load the DT overlay. One way to do that from user space is to use Pantelis'
+DT-Overlay configfs interface.
+
+This causes the simple FPGA bus go be probed and will do the following:
+ 1. Disable the FPGA bridges.
+ 2. Call the FPGA manager core to program the FPGA.
+ 3. Release the FPGA bridges.
+ 4. Call of_platform_populate resulting in device drivers getting probed.
+
+
+Requirements
+============
+
+ 1. An FPGA image that has a hardware block or blocks that use drivers that are
+ supported in the kernel.
+ 2. A device tree overlay (example is in the simple-fpga-bus bindings document).
+ 3. A FPGA manager driver supporting writing the FPGA.
+ 4. FPGA bridge drivers.
+
+The DT overlay includes bindings (documented in bindings/simple-fpga-bus.txt)
+that specify:
+ * Which FPGA manager to use.
+ * Which image file to load.
+ * Flags indicating whether this this image is for full reconfiguration or
+ partial.
+ * A list of FPGA bridges.
+ * Child nodes specifying the devices that will be added with appropriate
+ compatible strings, etc.
+
+Since this code uses the firmware interface to get the image and DT overlay,
+they currently have to be files on the file system. It doesn't have to be that
+way forever as DT bindings could be added to point to other sources for the
+image.
--
1.7.9.5
next prev parent reply other threads:[~2015-10-27 22:09 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-10-27 22:09 [PATCH v12 0/6] simple fpga bus and fpga bridge framework atull
2015-10-27 22:09 ` atull [this message]
[not found] ` <1445983755-24007-2-git-send-email-atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org>
2015-10-28 0:23 ` [PATCH v12 1/6] fpga: add usage documentation for simple fpga bus Moritz Fischer
2015-10-28 14:59 ` atull
2015-10-27 22:09 ` [PATCH v12 2/6] fpga: add bindings document " atull
2015-10-28 9:00 ` Steffen Trumtrar
2015-10-28 14:53 ` atull
2015-10-28 15:18 ` Moritz Fischer
2015-10-28 15:34 ` atull
2015-10-28 9:40 ` Steffen Trumtrar
2015-10-28 19:45 ` atull
2015-10-28 23:40 ` Rob Herring
2015-10-29 16:02 ` atull
2015-10-30 17:58 ` Rob Herring
2015-11-03 16:28 ` atull
2015-11-03 19:56 ` Rob Herring
2015-10-27 22:09 ` [PATCH v12 3/6] fpga: add simple-fpga-bus atull
2015-10-28 9:43 ` Steffen Trumtrar
2015-10-28 15:39 ` atull
2015-10-28 10:07 ` Josh Cartwright
2015-10-28 12:41 ` atull
2015-10-28 15:37 ` Moritz Fischer
2015-10-28 16:18 ` Josh Cartwright
[not found] ` <20151028161859.GJ8245-ew3lsbMjNqt5wtABiV/Xjqyly8cj88Ttqxv4g6HH51o@public.gmane.org>
2015-10-28 16:28 ` Moritz Fischer
2015-10-28 17:03 ` atull
2015-10-28 17:41 ` atull
2015-10-28 17:59 ` Josh Cartwright
2015-10-28 18:02 ` Josh Cartwright
2015-10-28 18:22 ` atull
2015-10-28 20:33 ` Moritz Fischer
2015-10-29 4:04 ` Rob Herring
2015-10-27 22:09 ` [PATCH v12 4/6] fpga: add fpga bridge framework atull
[not found] ` <1445983755-24007-5-git-send-email-atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org>
2015-10-28 9:50 ` Steffen Trumtrar
2015-10-28 15:31 ` atull
2015-10-27 22:09 ` [PATCH v12 5/6] ARM: socfpga: add bindings document for fpga bridge drivers atull
2015-10-28 9:29 ` Steffen Trumtrar
2015-10-28 15:53 ` atull
2015-10-28 23:44 ` Rob Herring
2015-10-29 15:04 ` atull
2015-10-27 22:09 ` [PATCH v12 6/6] ARM: socfpga: fpga bridge driver support atull
2015-10-28 10:13 ` Steffen Trumtrar
2015-10-28 12:51 ` atull
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=1445983755-24007-2-git-send-email-atull@opensource.altera.com \
--to=atull@opensource.altera.com \
--cc=corbet@lwn.net \
--cc=delicious.quinoa@gmail.com \
--cc=devicetree@vger.kernel.org \
--cc=dinguyen@opensource.altera.com \
--cc=galak@codeaurora.org \
--cc=gregkh@linuxfoundation.org \
--cc=ijc+devicetree@hellion.org.uk \
--cc=joshc@ni.com \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=michal.simek@xilinx.com \
--cc=monstr@monstr.eu \
--cc=moritz.fischer@ettus.com \
--cc=pantelis.antoniou@konsulko.com \
--cc=pawel.moll@arm.com \
--cc=robh+dt@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).