Message-ID: <57dd6b7f-6f30-9fc5-0cbc-7d28a2f65f6a@gmail.com>
Date:   Thu, 9 Mar 2023 21:54:32 +0100
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Subject: Re: [PATCH v3 2/4] firmware: Add support for Qualcomm Secure
 Execution Environment SCM interface
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To:     Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        Bjorn Andersson <andersson@kernel.org>
Cc:     Andy Gross <agross@kernel.org>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        Ard Biesheuvel <ardb@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Johan Hovold <johan@kernel.org>,
        Sudeep Holla <sudeep.holla@arm.com>,
        Ilias Apalodimas <ilias.apalodimas@linaro.org>,
        Srinivas Kandagatla <srinivas.kandagatla@linaro.org>,
        Sumit Garg <sumit.garg@linaro.org>,
        Steev Klimaszewski <steev@kali.org>,
        linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20230305022119.1331495-1-luzmaximilian@gmail.com>
 <20230305022119.1331495-3-luzmaximilian@gmail.com>
 <84e6cfd8-ee4b-a5f4-5249-d87df9909246@linaro.org>
 <fa9cfc41-1d6c-1003-e6d9-6a1545487177@gmail.com>
 <98f20683-bb1d-47c2-18ca-f3de61c9a91f@linaro.org>
From:   Maximilian Luz <luzmaximilian@gmail.com>
In-Reply-To: <98f20683-bb1d-47c2-18ca-f3de61c9a91f@linaro.org>
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On 3/9/23 09:45, Dmitry Baryshkov wrote:
> On 08/03/2023 15:59, Maximilian Luz wrote:
>> On 3/7/23 16:32, Dmitry Baryshkov wrote:
>>> On 05/03/2023 04:21, Maximilian Luz wrote:

[...]

>>>> +int qseecom_scm_call(struct qseecom_device *qsee, const struct qcom_scm_desc *desc,
>>>> +             struct qseecom_scm_resp *res);
>>>> +
>>>> +
>>>> +/* -- Secure App interface. ------------------------------------------------- */
>>>> +
>>>> +#define QSEECOM_MAX_APP_NAME_SIZE            64
>>>> +
>>>> +int qseecom_app_get_id(struct qseecom_device *qsee, const char *app_name, u32 *app_id);
>>>> +int qseecom_app_send(struct qseecom_device *qsee, u32 app_id, struct qseecom_dma *req,
>>>> +             struct qseecom_dma *rsp);
>>>
>>> I think that only these calls should be made public / available to other modules. qseecom_scm_call also is an internal helper.
>>
>> So move all calls to qcom_scm and only make these two public? Or move only
>> qseecom_scm_call() to qcom_scm (which would require to make it public there,
>> however). Or how would you want this to look?
> 
> I think we can make it with just these calls being public. Or even with just the second one being public and available to other drivers. If the app_id is a part of qseecom_app_device, we can pass that device to the qseecom_app_send(). And qseecom_app_get_id() becomes a part of app registration.

Right, with the bus structure, we only really need qseecom_app_send().

I'm still a bit concerned about things maybe getting too complex for
qcom_scm with the blocking/re-entrant calls (and maybe other future
stuff), but I guess we can always try to break things up when/if we get
around to that.

I'll try to implement that and your other suggestions and see how that
goes. I think that should work quite well overall.

Thanks again for your review and comments.

Regards,
Max