Subject: Re: [PATCH v2 5/8] dt-bindings: misc: add property to support
 non-secure DSP
To:     Bjorn Andersson <bjorn.andersson@linaro.org>
Cc:     robh+dt@kernel.org, gregkh@linuxfoundation.org,
        devicetree@vger.kernel.org, ekangupt@qti.qualcomm.com,
        jeyr@codeaurora.org, bkumar@qti.qualcomm.com,
        linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org
References: <20211209120626.26373-1-srinivas.kandagatla@linaro.org>
 <20211209120626.26373-6-srinivas.kandagatla@linaro.org>
 <Ybdq4qAeqK8C8Yvc@ripper>
From:   Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Message-ID: <4fd726d7-608f-0ddd-7338-6f8cac3ef775@linaro.org>
Date:   Thu, 16 Dec 2021 11:27:46 +0000
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On 13/12/2021 15:46, Bjorn Andersson wrote:
> On Thu 09 Dec 04:06 PST 2021, Srinivas Kandagatla wrote:
> 
>> From: Jeya R <jeyr@codeaurora.org>
>>
>> Add property to set DSP domain as non-secure.
>>
>> ADSP/MDSP/SDSP are by default secured, where as CDSP can be either be
>> secured/unsecured.
>> non-secured Compute DSP would allow users to load unsigned process
>> and run hexagon instructions, but limiting access to secured hardware
>> within the DSP.
>>
>> Based on this flag device nodes for secured and unsecured are created.
>>
>> Signed-off-by: Jeya R <jeyr@codeaurora.org>
>> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
>> ---
>>
>> This patch has dependency this yaml conversion patch:
>> https://lore.kernel.org/lkml/20211208101508.24582-1-david@ixit.cz/T/
>>
>>   Documentation/devicetree/bindings/misc/qcom,fastrpc.yaml | 5 +++++
>>   1 file changed, 5 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/misc/qcom,fastrpc.yaml b/Documentation/devicetree/bindings/misc/qcom,fastrpc.yaml
>> index f42ab208a7fc..f0df0a3bf69f 100644
>> --- a/Documentation/devicetree/bindings/misc/qcom,fastrpc.yaml
>> +++ b/Documentation/devicetree/bindings/misc/qcom,fastrpc.yaml
>> @@ -29,6 +29,11 @@ properties:
>>           - sdsp
>>           - cdsp
>>   
>> +  qcom,non-secure-domain:
>> +    type: boolean
>> +    description: >
>> +      Property to specify that dsp domain is non-secure.

> 
> "non-secure" feels vague, how about expressing it as "Specifies that the
> domains of this DSP instance may run unsigned programs."

TBH I dont mind either of this, but looking at some existing bindings I 
see similar pattern of properties like.. "st,non-secure-otp"

> 
> Perhaps even go so far to name the property
> qcom,allow-unsigned-programs? (Or some other word for "program"?)

Do you think adding more details in the description would help?

--srini
> 
> Regards,
> Bjorn
> 
>> +
>>     '#address-cells':
>>       const: 1
>>   
>> -- 
>> 2.21.0
>>