Re: [PATCH v3 2/3] dt-bindings: crypto: document Exynos5433 SlimSSS

From: Kamil Konieczny
Date: Thu Jan 31 2019 - 11:45:55 EST


Hi,

On 30.01.2019 17:51, Rob Herring wrote:
> On Thu, Jan 24, 2019 at 04:45:20PM +0100, Kamil Konieczny wrote:
>> Document DT bindings for crypto Samsung Exynos5433 SlimSSS (Slim Security
>> SubSystem) IP.
>>
>> Reviewed-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
>> Signed-off-by: Kamil Konieczny <k.konieczny@xxxxxxxxxxxxxxxxxxx>
>> ---
>> .../devicetree/bindings/crypto/samsung-sss.txt | 14 +++++++++++---
>> 1 file changed, 11 insertions(+), 3 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/crypto/samsung-sss.txt b/Documentation/devicetree/bindings/crypto/samsung-sss.txt
>> index 7a5ca56683cc..d9af679d38ab 100644
>> --- a/Documentation/devicetree/bindings/crypto/samsung-sss.txt
>> +++ b/Documentation/devicetree/bindings/crypto/samsung-sss.txt
>> @@ -1,4 +1,4 @@
>> -Samsung SoC SSS (Security SubSystem) module
>> +Samsung SoC SSS (Security SubSystem) and SlimSSS module
>>
>> The SSS module in S5PV210 SoC supports the following:
>> -- Feeder (FeedCtrl)
>> @@ -15,6 +15,12 @@ supports the following also:
>> -- True Random Number Generator (TRNG)
>> -- Secure Key Manager
>>
>> +Exynos5433 has both SSS and SlimSSS module.
>
> That's not really relevant to the binding.
>
> What do the SSS and SlimSSS share? Only that both have a single reg and
> interrupt based on the binding? This should probably be just 2
> documents. If not now, it will have to be when converted to a DT schema.

They share hardware design, slimSSS is stripped-down SSS version,
and can be handled by the same crypto s5p-sss driver. The register
layout is the same for FeedControl (DMA) and AES crypt function.

Do you prefer to put this description in new file samsung-slimsss.txt ?
If yes, I can send v4, so it can be done right from beginning.

>> +SlimSSS in Exynos5433 supports:
>> +-- Feeder (FeedCtrl)
>> +-- Advanced Encryption Standard (AES)
>> +-- SHA-1/SHA-256/HMAC (SHA-1/SHA-256)
>> +
>> Required properties:
>>
>> - compatible : Should contain entries for this and backward compatible
>> @@ -22,11 +28,13 @@ Required properties:
>> - "samsung,s5pv210-secss" for S5PV210 SoC.
>> - "samsung,exynos4210-secss" for Exynos4210, Exynos4212, Exynos4412, Exynos5250,
>> Exynos5260 and Exynos5420 SoCs.
>> + - "samsung,exynos5433-slim-sss" for Exynos5433 SoCs.
>> - reg : Offset and length of the register set for the module
>> - interrupts : interrupt specifiers of SSS module interrupts (one feed
>> control interrupt).
>>
>> - clocks : list of clock phandle and specifier pairs for all clocks listed in
>> clock-names property.
>> -- clock-names : list of device clock input names; should contain one entry
>> - "secss".
>> +- clock-names : list of device clock input names; should contain "pclk" and
>> + "aclk" for slim-sss in Exynos5433, and one entry "secss" for
>> + other compatibles.
>> --
>> 2.20.0

--
Best regards,
Kamil Konieczny
Samsung R&D Institute Poland