[U-Boot] [PATCH] dm: Update README.txt to clarify device tree usage
In the section about Device Trees add a paragraph at the end that clarifies how we decide of a tree is valid or not. We say that all bindings must either be in the specification (link provided) or in our device-tree-bindings directory. We say that most of these come from the Linux Kernel and as such some design decisions are made for us already, but that in most cases we wish to retain compatibility.
Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com Signed-off-by: Tom Rini trini@konsulko.com --- doc/driver-model/README.txt | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/doc/driver-model/README.txt b/doc/driver-model/README.txt index d6fa5c485793..e949ff63bae4 100644 --- a/doc/driver-model/README.txt +++ b/doc/driver-model/README.txt @@ -449,6 +449,15 @@ The driver model tree is intended to mirror that of the device tree. The root driver is at device tree offset 0 (the root node, '/'), and its children are the children of the root node.
+In order for a device tree to be valid, the content must be correct with +respect to either device tree specification +(https://www.devicetree.org/specifications/) or the device tree bindings that +are found in the doc/device-tree-bindings directory. When not U-Boot specific +the bindings in this directory tend to come from the Linux Kernel. As such +certain design decisions may have been made already for us in terms of how +specific devices are described and bound. In most circumstances we wish to +retain compatibility without additional changes being made to the device tree +source files.
Declaring Uclasses ------------------
Hi Tom,
On 31 August 2018 at 09:59, Tom Rini trini@konsulko.com wrote:
In the section about Device Trees add a paragraph at the end that clarifies how we decide of a tree is valid or not. We say that all bindings must either be in the specification (link provided) or in our device-tree-bindings directory. We say that most of these come from the Linux Kernel and as such some design decisions are made for us already, but that in most cases we wish to retain compatibility.
Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com Signed-off-by: Tom Rini trini@konsulko.com
doc/driver-model/README.txt | 9 +++++++++ 1 file changed, 9 insertions(+)
Reviewed-by: Simon Glass sjg@chromium.org
nits below
diff --git a/doc/driver-model/README.txt b/doc/driver-model/README.txt index d6fa5c485793..e949ff63bae4 100644 --- a/doc/driver-model/README.txt +++ b/doc/driver-model/README.txt @@ -449,6 +449,15 @@ The driver model tree is intended to mirror that of the device tree. The root driver is at device tree offset 0 (the root node, '/'), and its children are the children of the root node.
+In order for a device tree to be valid, the content must be correct with +respect to either device tree specification +(https://www.devicetree.org/specifications/) or the device tree bindings that +are found in the doc/device-tree-bindings directory. When not U-Boot specific
When not U-Boot-specific,
+the bindings in this directory tend to come from the Linux Kernel. As such +certain design decisions may have been made already for us in terms of how +specific devices are described and bound. In most circumstances we wish to +retain compatibility without additional changes being made to the device tree +source files.
Declaring Uclasses
-- 2.7.4
Regards, Simon
On Wed, Sep 05, 2018 at 09:24:44AM -0600, Simon Glass wrote:
Hi Tom,
On 31 August 2018 at 09:59, Tom Rini trini@konsulko.com wrote:
In the section about Device Trees add a paragraph at the end that clarifies how we decide of a tree is valid or not. We say that all bindings must either be in the specification (link provided) or in our device-tree-bindings directory. We say that most of these come from the Linux Kernel and as such some design decisions are made for us already, but that in most cases we wish to retain compatibility.
Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com Signed-off-by: Tom Rini trini@konsulko.com
doc/driver-model/README.txt | 9 +++++++++ 1 file changed, 9 insertions(+)
Reviewed-by: Simon Glass sjg@chromium.org
nits below
diff --git a/doc/driver-model/README.txt b/doc/driver-model/README.txt index d6fa5c485793..e949ff63bae4 100644 --- a/doc/driver-model/README.txt +++ b/doc/driver-model/README.txt @@ -449,6 +449,15 @@ The driver model tree is intended to mirror that of the device tree. The root driver is at device tree offset 0 (the root node, '/'), and its children are the children of the root node.
+In order for a device tree to be valid, the content must be correct with +respect to either device tree specification +(https://www.devicetree.org/specifications/) or the device tree bindings that +are found in the doc/device-tree-bindings directory. When not U-Boot specific
When not U-Boot-specific,
+the bindings in this directory tend to come from the Linux Kernel. As such +certain design decisions may have been made already for us in terms of how +specific devices are described and bound. In most circumstances we wish to +retain compatibility without additional changes being made to the device tree +source files.
Declaring Uclasses
Thanks, I'll add the comma when I commit, barring further comments from people.
On Fri, Aug 31, 2018 at 11:59:11AM -0400, Tom Rini wrote:
In the section about Device Trees add a paragraph at the end that clarifies how we decide of a tree is valid or not. We say that all bindings must either be in the specification (link provided) or in our device-tree-bindings directory. We say that most of these come from the Linux Kernel and as such some design decisions are made for us already, but that in most cases we wish to retain compatibility.
Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com Signed-off-by: Tom Rini trini@konsulko.com Reviewed-by: Simon Glass sjg@chromium.org
Applied to u-boot/master, thanks!
participants (2)
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Simon Glass -
Tom Rini