[PATCH 1/3] dt: Add DT bindings documentation for SUNXI Security System

On 24.05.2014 21:43, Marek Vasut wrote:

On Saturday, May 24, 2014 at 09:20:03 PM, Tomasz Figa wrote:

quoted

Hi Marek,

On 24.05.2014 13:21, Marek Vasut wrote:

quoted

On Thursday, May 22, 2014 at 05:09:54 PM, LABBE Corentin wrote:

Missing commit message. Please fix this and send a V2.

quoted

Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
---

 Documentation/devicetree/bindings/crypto/sunxi-ss.txt | 9 +++++++++
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 Documentation/devicetree/bindings/crypto/sunxi-ss.txt

diff --git a/Documentation/devicetree/bindings/crypto/sunxi-ss.txt

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@@ -0,0 +1,9 @@
+* Allwinner Security System found on A20 SoC
+
+Required properties:
+- compatible : Should be "allwinner,sun7i-a20-crypto".

Why sun7i-a20 ? Is the crypto unit different in other sunxi chips ? Can
that not be described by DT props ?

A widely used convention is to define compatible strings after first
SoCs on which particular IP blocks appear. It is quite common among IP
blocks for which there is no well defined versioning scheme.

Well yeah, that's fine. But in this case, "sun7i" is the entire group of CPUs 
manufactured by AW. I find that information redundant, the "allwinner,a20-
crypto" would suffice. But I wonder if that IP block might have appeared even 
earlier ? Or if it is CPU family specific, thus "allwinner,sun7i-crypto" would 
be a better string ?

I'm not aware of Allwinner naming schemes too much, so please correct me
if I'm wrong, but if A20 implies sun7i, then "allwinner,a20-crypto"
would be better indeed.

Whether it was really the first SoC is another thing. Obviously this
needs to be checked, although it isn't really that important. For this
particular naming scheme you need to specify all the SoCs for which
given compatible string can be used for this IP anyway, because there is
usually no other source of information about this available (except
directly comparing two datasheets...).

Best regards,
Tomasz