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Date:   Wed, 27 Jul 2022 13:38:55 +0200
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Subject: Re: [PATCH 4/4] dt-bindings: firmware: Add Qualcomm UEFI Secure
 Application client
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To:     Maximilian Luz <luzmaximilian@gmail.com>,
        Sudeep Holla <sudeep.holla@arm.com>
Cc:     Andy Gross <agross@kernel.org>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Ard Biesheuvel <ardb@kernel.org>,
        Konrad Dybcio <konrad.dybcio@somainline.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Steev Klimaszewski <steev@kali.org>,
        Shawn Guo <shawn.guo@linaro.org>,
        Cristian Marussi <cristian.marussi@arm.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-arm-msm@vger.kernel.org, linux-efi@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20220723224949.1089973-1-luzmaximilian@gmail.com>
 <20220723224949.1089973-5-luzmaximilian@gmail.com>
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 <829c8fee-cae5-597d-933d-784b4b57bd73@gmail.com>
 <20220726154138.74avqs6iqlzqpzjk@bogus>
 <d1bc99bb-82ce-aa6e-7fad-e9309fa1c19b@gmail.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <d1bc99bb-82ce-aa6e-7fad-e9309fa1c19b@gmail.com>
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On 26/07/2022 19:01, Maximilian Luz wrote:
> On 7/26/22 17:41, Sudeep Holla wrote:
>> On Tue, Jul 26, 2022 at 05:15:41PM +0200, Maximilian Luz wrote:
>>>
>>> So ultimately I think it's better to add a DT entry for it.
>>
>> I disagree for the reason that once you discover more apps running on the
>> secure side, you want to add more entries and update DT on the platform
>> every time you discover some new firmware entity and you wish to interact
>> with it from the non-secure side.
> 
> Just as you'll have to add a driver to the kernel and update whatever is
> probing the TrEE interface and add those strings to that interface. If
> you then start doing SoC-specific lists, I think you'd be pretty much
> re-implementing a DT in the kernel driver...

But you don't have any of these names in the DT either. Your DT node
only indicates the presence of your driver, but does not hold any
additional information like these IDs.

Basically we start modelling firmware components in devicetree. :/

Best regards,
Krzysztof