Difference between revisions of "Device Trees"

From eLinux.org
Jump to: navigation, search
(Mailing list discussion: fix FDT acronym usage)
(Redirect this page (plural) to the 'device tree' (singular) page.)
 
(23 intermediate revisions by 6 users not shown)
Line 1: Line 1:
== Introduction ==
+
#REDIRECT [[Device Tree]]
Device trees are a method used by the operating system to determine the hardware
+
configuration.  Device trees were originally developed for the PowerPC OpenFirmware
+
software, as a way to encapsulate platform information and convey it to the
+
operating system.  The Linux kernel currently can read device tree information
+
for x86 and ppc architectures.  There is interest in extending support for
+
device trees to other platforms, to unify the handling of platform description
+
across kernel architectures.
+
 
+
A device tree can be built at compile-time and statically linked into the kernel.
+
Or it can be created by the bootloader firmware and passed to the kernel at
+
boot time. The operating system reads the device tree and uses it to figure out
+
such things like how much memory is available, bus layout, list of devices, and
+
how interrupts are connected.
+
 
+
The Linux kernel includes a "compiler" which takes a device tree description
+
in "dts" format and produces a binary, "dtc", format, suitable for linking
+
into the kernel.  See scripts/dtc in the kernel source directory.
+
 
+
There is documentation describing device tree support (with information current as of 2006) in the
+
Linux kernel source tree at:
+
[http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blob_plain;f=Documentation/powerpc/booting-without-of.txt;hb=HEAD Documentation/powerpc/booting-without-of.txt]
+
 
+
== Resources ==
+
=== Presentations and Papers ===
+
"Using the Device Tree to Describe
+
Embedded Hardware" - Grant Likely, Embedded Linux Conference, 2008
+
http://www.celinux.org/elc08_presentations/glikely--device-tree.pdf
+
 
+
"A Symphony of Flavours: Using the device tree to describe embedded
+
hardware" - Grant Likely and Josh Boyer - paper for OLS 2008
+
http://ols.fedoraproject.org/OLS/Reprints-2008/likely2-reprint.pdf
+
 
+
Note from Device Tree Birds of a Feature session at OLS 2008:
+
http://lists.ozlabs.org/pipermail/devicetree-discuss/2008-July/000004.html
+
 
+
==== Coming Up Soon ====
+
Grant's talk at Plumber's conference 2009 - http://linuxplumbersconf.org/ocw/proposals/47
+
 
+
=== Device-tree Mailing List ===
+
https://lists.ozlabs.org/listinfo/devicetree-discuss
+
 
+
=== Mailing list discussion ===
+
Recent discussion of "Flattened Device Tree" work on linux-embedded mailing list:
+
http://www.mail-archive.com/linux-embedded@vger.kernel.org/msg01721.html
+
 
+
Russel King is against adding support for FDT to the ARM platform:
+
http://lkml.indiana.edu/hypermail/linux/kernel/0905.3/01942.html
+
(see whole thread for interesting discussion)
+
 
+
David Gibson defends FDT:
+
http://lkml.indiana.edu/hypermail/linux/kernel/0905.3/02304.html
+
 
+
=== Xilink device tree generator documentation ===
+
Xilinx provides a device-tree generator:
+
http://xilinx.wikidot.com/device-tree-generator
+
"The device tree generator is a Xilinx EDK tool that plugs into the Automatic BSP Generation features of the tool, XPS"
+

Latest revision as of 16:55, 5 September 2013

Redirect to: