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Message-ID: <257e11b5-29b5-78c6-882b-ec3bb64ee28b@quicinc.com>
Date:   Mon, 15 May 2023 14:02:11 +0530
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Subject: Re: [PATCH v3 04/10] nvmem: qfprom: Add support for secure reading on
 QDU1000/QRU1000
Content-Language: en-US
To:     Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
CC:     Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Srinivas Kandagatla <srinivas.kandagatla@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        <linux-arm-msm@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <devicetree@vger.kernel.org>
References: <20230512122134.24339-1-quic_kbajaj@quicinc.com>
 <20230512122134.24339-5-quic_kbajaj@quicinc.com>
 <68f9bee2-5a5b-2962-6c3d-e73ade371545@linaro.org>
 <CAA8EJppObh3h8sxB_f9SQy7EQ1Gfhe9EbzV=wsUbVNj9PtX=GA@mail.gmail.com>
From:   Komal Bajaj <quic_kbajaj@quicinc.com>
In-Reply-To: <CAA8EJppObh3h8sxB_f9SQy7EQ1Gfhe9EbzV=wsUbVNj9PtX=GA@mail.gmail.com>
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On 5/12/2023 11:01 PM, Dmitry Baryshkov wrote:
> On Fri, 12 May 2023 at 20:01, Krzysztof Kozlowski
> <krzysztof.kozlowski@linaro.org> wrote:
>> On 12/05/2023 14:21, Komal Bajaj wrote:
>>> Add qfprom driver support for QDU1000/QRU1000 SOCs.
>>>
>>> Signed-off-by: Komal Bajaj <quic_kbajaj@quicinc.com>
>>> ---
>>>   drivers/nvmem/qfprom.c | 5 +++++
>>>   1 file changed, 5 insertions(+)
>>>
>>> diff --git a/drivers/nvmem/qfprom.c b/drivers/nvmem/qfprom.c
>>> index 20662e2d3732..12a7981a8a71 100644
>>> --- a/drivers/nvmem/qfprom.c
>>> +++ b/drivers/nvmem/qfprom.c
>>> @@ -109,6 +109,10 @@ struct qfprom_soc_compatible_data {
>>>        bool secure;
>>>   };
>>>
>>> +static const struct qfprom_soc_compatible_data qdu1000_qfprom = {
>>> +     .secure = true
>>> +};
>>> +
>>>   static const struct nvmem_keepout sc7180_qfprom_keepout[] = {
>>>        {.start = 0x128, .end = 0x148},
>>>        {.start = 0x220, .end = 0x228}
>>> @@ -490,6 +494,7 @@ static int qfprom_probe(struct platform_device *pdev)
>>>
>>>   static const struct of_device_id qfprom_of_match[] = {
>>>        { .compatible = "qcom,qfprom",},
>>> +     { .compatible = "qcom,qdu1000-qfprom", .data = &qdu1000_qfprom},
>>>        { .compatible = "qcom,sc7180-qfprom", .data = &sc7180_qfprom},
>> I have doubts that this is still compatible with qcom,qfprom. It uses
>> entirely different read method. That's why generic fallbacks are bad,
>> one more case to my growing list of awesome examples. :)
Okay, will do that.
> Yes, it looks like it should be 'qcom,qdu1000-qfprom",
> "qcom,scm-qfprom". And possibly a separate driver for scm-qfprom.
The only difference here is in read method, which can be controlled by a 
single property,
do we really need to write a separate driver for just reading secure 
feature register.

Thanks,
Komal
>
>