Message-ID: <9155d7ce-9799-9bd7-d26b-c9997599332c@quicinc.com>
Date:   Fri, 27 Jan 2023 17:07:04 +0530
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Subject: Re: [PATCH v4 1/2] dt-bindings: arm: qcom: Document the sc7280 CRD
 Pro boards
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To:     Doug Anderson <dianders@chromium.org>
CC:     Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        <andersson@kernel.org>, Matthias Kaehlcke <mka@chromium.org>,
        <agross@kernel.org>, <robh+dt@kernel.org>,
        <krzysztof.kozlowski+dt@linaro.org>, <konrad.dybcio@linaro.org>,
        <linux-arm-msm@vger.kernel.org>, <devicetree@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
References: <20221216112918.1243-1-quic_rjendra@quicinc.com>
 <Y5x+WEwTtpoV0gaR@google.com>
 <fd23e295-fea0-1b0a-752c-3cce26b57346@quicinc.com>
 <Y6HHCrl0q5BhrHOY@google.com>
 <e269300d-539e-9eb8-8b3c-d309f3abca1b@quicinc.com>
 <bbc3c257-0a49-4c80-4586-c179c8997b50@linaro.org>
 <CAD=FV=X3DyMrEWESV2cWvqg_TQYnj+VGFBQodAp+gfbhBz6X3Q@mail.gmail.com>
 <9f6bd192-2a42-0a23-0032-df8b01921bdc@linaro.org>
 <CAD=FV=U6KhJR+9q49=T3-aYppukRNmLrgvhaxP_ZtLP=VgSaDA@mail.gmail.com>
 <18c2bd9a-0216-c4fc-773e-601aea030b48@quicinc.com>
 <CAD=FV=WJWnGKgw74nW_VteSwaMswskT7_sQ3iz3YZvsBMfOyxA@mail.gmail.com>
From:   Rajendra Nayak <quic_rjendra@quicinc.com>
In-Reply-To: <CAD=FV=WJWnGKgw74nW_VteSwaMswskT7_sQ3iz3YZvsBMfOyxA@mail.gmail.com>
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On 1/27/2023 5:50 AM, Doug Anderson wrote:
> Hi,
> 
> On Mon, Jan 9, 2023 at 8:21 PM Rajendra Nayak <quic_rjendra@quicinc.com> wrote:
>>
>>
>> On 1/10/2023 3:12 AM, Doug Anderson wrote:
>>> Hi,
>>>
>>> On Mon, Jan 9, 2023 at 1:36 PM Dmitry Baryshkov
>>> <dmitry.baryshkov@linaro.org> wrote:
>>>>
>>>> On 09/01/2023 23:00, Doug Anderson wrote:
>>>>> Hi,
>>>>>
>>>>> On Tue, Dec 20, 2022 at 9:12 AM Dmitry Baryshkov
>>>>> <dmitry.baryshkov@linaro.org> wrote:
>>>>>>
>>>>>> On 20/12/2022 18:20, Rajendra Nayak wrote:
>>>>>>>
>>>>>>>
>>>>>>> On 12/20/2022 8:00 PM, Matthias Kaehlcke wrote:
>>>>>>>> On Tue, Dec 20, 2022 at 10:30:32AM +0530, Rajendra Nayak wrote:
>>>>>>>>>
>>>>>>>>> On 12/16/2022 7:49 PM, Matthias Kaehlcke wrote:
>>>>>>>>>> On Fri, Dec 16, 2022 at 04:59:17PM +0530, Rajendra Nayak wrote:
>>>>>>>>>>> Add compatibles for the Pro SKU of the sc7280 CRD boards
>>>>>>>>>>> which come with a Pro variant of the qcard.
>>>>>>>>>>> The Pro qcard variant has smps9 from pm8350c ganged up with
>>>>>>>>>>> smps7 and smps8.
>>>>>>>>>>>
>>>>>>>>>>> Signed-off-by: Rajendra Nayak <quic_rjendra@quicinc.com>
>>>>>>>>>>> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>>>>>>>>>>> Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
>>>>>>>>>>> ---
>>>>>>>>>>> v4 changes:
>>>>>>>>>>> Added the zoglin-sku1536 compatible along with hoglin-sku1536.
>>>>>>>>>>> Zoglin is same as the Hoglin variant, with the SPI Flash reduced
>>>>>>>>>>> from 64MB to 8MB
>>>>>>>>>>>
>>>>>>>>>>>       Documentation/devicetree/bindings/arm/qcom.yaml | 6 ++++++
>>>>>>>>>>>       1 file changed, 6 insertions(+)
>>>>>>>>>>>
>>>>>>>>>>> diff --git a/Documentation/devicetree/bindings/arm/qcom.yaml
>>>>>>>>>>> b/Documentation/devicetree/bindings/arm/qcom.yaml
>>>>>>>>>>> index 1b5ac6b02bc5..07771d4c91bd 100644
>>>>>>>>>>> --- a/Documentation/devicetree/bindings/arm/qcom.yaml
>>>>>>>>>>> +++ b/Documentation/devicetree/bindings/arm/qcom.yaml
>>>>>>>>>>> @@ -558,6 +558,12 @@ properties:
>>>>>>>>>>>                 - const: google,hoglin
>>>>>>>>>>>                 - const: qcom,sc7280
>>>>>>>>>>> +      - description: Qualcomm Technologies, Inc. sc7280 CRD Pro
>>>>>>>>>>> platform (newest rev)
>>>>>>>>>>> +        items:
>>>>>>>>>>> +          - const: google,zoglin-sku1536
>>>>>>>>>>> +          - const: google,hoglin-sku1536
>>>>>>>>>>
>>>>>>>>>> Is there actually such a thing as a 'hoglin-sku1536', i.e. the Pro
>>>>>>>>>> qcard
>>>>>>>>>> with 64MB of SPI flash, or do they all have 8MB of flash?
>>>>>>>>>
>>>>>>>>> The SPI flash is on the CRD mother-board and not on the qcards, so if
>>>>>>>>> you replace
>>>>>>>>> the qcards on the CRDs with 64MB flash you would need the
>>>>>>>>> hoglin-sku1536 to
>>>>>>>>> boot on those.
>>>>>>>>
>>>>>>>> With such a configuration how does the bootloader know it should pass
>>>>>>>> the kernel
>>>>>>>> the device tree for 'hoglin-sku1536' (pro) and not the non-pro
>>>>>>>> variant? IIUC the
>>>>>>>> device tree is selected based on pin strappings on the mother-board,
>>>>>>>> not the
>>>>>>>> qcard.
>>>>>>>
>>>>>>> The device tree is selected based on the pin strappings _and_ additional
>>>>>>> logic
>>>>>>> to dynamically identify modem/non-modem(wifi) as well as pro/non-pro
>>>>>>> SKUs which
>>>>>>> was added in the bootloaders.
>>>>>>
>>>>>> Just to clarify things, when you mention pro SKU, is it a separate SoC
>>>>>> revision (like sc7280-pro vs bare sc7280), or is it a CRD revision (CRD
>>>>>> Pro vs bare CRD)?
>>>>>
>>>>> I guess Rajendra never responded, but since I know the answer: it's a
>>
>> Thanks Doug for the clarifications, I seem to have missed responding to this
>> once I was back from vacation,
>>
>>>>> different SoC revision. ...but the SoC in this case is on a daughter
>>>>> card, so you could remove the daughter card containing the SoC and put
>>>>> a new daughtercard on. That would have the effect of making an old CRD
>>>>> revision have the new Pro SKU SoC.
>>>>
>>>> So, this is a new SoC. Is it 100% compatible with the sc7280? In other
>>>> words: does it require any additional customizations (in OPP tables, in
>>>> frequences, speed bins, etc)?
>>
>> Yes, the OPP differences are taken care of with no changes needed in kernel.
>> We describe a superset of *all* OPPs supported by a SoC family in DT and the
>> cpufreq driver then queries the firmware for supported OPPs on a given
>> SoC variant and ends up disabling the rest.
> 
> I saw that Bjorn just send out a pull request but it didn't include
> this patch. Bjorn: are you expecting anything from Rajendra here, or
> did it just get missed? I think Rajendra responded to all of Dmitry's
> comments, but I could be mistaken.

Yes, there is nothing outstanding for these patches, they should be good
to go, Bjorn can they be pulled in?

> 
> -Doug