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Message-ID: <2b870e62-9b74-7eae-7e91-eae26361b1e6@quicinc.com>
Date:   Fri, 28 Jul 2023 19:24:28 +0530
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Subject: Re: [PATCH v5 1/2] dt-bindings: nvmem: sec-qfprom: Add bindings for
 secure qfprom
Content-Language: en-US
To:     Rob Herring <robh@kernel.org>
CC:     <agross@kernel.org>, <andersson@kernel.org>,
        <konrad.dybcio@linaro.org>, <krzysztof.kozlowski+dt@linaro.org>,
        <conor+dt@kernel.org>, <srinivas.kandagatla@linaro.org>,
        <linux-arm-msm@vger.kernel.org>, <devicetree@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
References: <20230724083849.8277-1-quic_kbajaj@quicinc.com>
 <20230724083849.8277-2-quic_kbajaj@quicinc.com>
 <20230726164039.GA1558299-robh@kernel.org>
From:   Komal Bajaj <quic_kbajaj@quicinc.com>
In-Reply-To: <20230726164039.GA1558299-robh@kernel.org>
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On 7/26/2023 10:10 PM, Rob Herring wrote:
> On Mon, Jul 24, 2023 at 02:08:48PM +0530, Komal Bajaj wrote:
>> This patch adds bindings for secure qfprom found in QCOM SOCs.
>> Secure QFPROM driver is based on simple nvmem framework.
>>
>> Signed-off-by: Komal Bajaj <quic_kbajaj@quicinc.com>
>> ---
>>   .../bindings/nvmem/qcom,sec-qfprom.yaml       | 58 +++++++++++++++++++
>>   1 file changed, 58 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/nvmem/qcom,sec-qfprom.yaml
>>
>> diff --git a/Documentation/devicetree/bindings/nvmem/qcom,sec-qfprom.yaml b/Documentation/devicetree/bindings/nvmem/qcom,sec-qfprom.yaml
>> new file mode 100644
>> index 000000000000..1425ced36fdf
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/nvmem/qcom,sec-qfprom.yaml
>> @@ -0,0 +1,58 @@
>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/nvmem/qcom,sec-qfprom.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: Qualcomm Technologies Inc, Secure QFPROM Efuse
>> +
>> +maintainers:
>> +  - Komal Bajaj <quic_kbajaj@quicinc.com>
>> +
>> +description: |
> Don't need '|'

Okay, will drop this.
Just a doubt here, when do we use this '|' symbol, I

  thought we will use this when
we have multi-line description/value.

>
>> +  For some of the Qualcomm SoC's, it is possible that
>> +  the qfprom region is protected from non-secure access.
>> +  In such situations, linux will have to use secure calls
> s/linux/the OS/

Will do it.

>
>> +  to read the region.
> Wrap lines at 80
>
> The wording for this is strange. Only sometimes for this binding do
> secure calls have to be used? If you are using secure calls, does that
> mean the 'reg' address is not directly accessible.

For this binding, we will always use secure calls because the 'reg' 
address is not directly
accessible to the OS.

Thanks
Komal

>
>> +
>> +allOf:
>> +  - $ref: nvmem.yaml#
>> +
>> +properties:
>> +  compatible:
>> +    items:
>> +      - enum:
>> +          - qcom,qdu1000-sec-qfprom
>> +      - const: qcom,sec-qfprom
>> +
>> +  reg:
>> +    items:
>> +      - description: The secure qfprom corrected region.
>> +
>> +required:
>> +  - compatible
>> +  - reg
>> +
>> +unevaluatedProperties: false
>> +
>> +examples:
>> +  - |
>> +    #include <dt-bindings/clock/qcom,gcc-sc7180.h>
>> +
>> +    soc {
>> +      #address-cells = <2>;
>> +      #size-cells = <2>;
>> +
>> +      efuse@221c8000 {
>> +        compatible = "qcom,qdu1000-sec-qfprom", "qcom,sec-qfprom";
>> +        reg = <0 0x221c8000 0 0x1000>;
>> +        #address-cells = <1>;
>> +        #size-cells = <1>;
>> +
>> +        multi_chan_ddr: multi-chan-ddr@12b {
>> +          reg = <0x12b 0x1>;
>> +          bits = <0 2>;
>> +        };
>> +      };
>> +    };
>> +
>> --
>> 2.40.1
>>