Re: [PATCH 1/4] arm64: dts: qcom: sa8775p: pmic: remove the PON modes

Shazad Hussain
2023-04-18T09:55:45Z

On 4/18/2023 3:13 PM, Konrad Dybcio wrote:
>
>
> On 18.04.2023 06:39, Shazad Hussain wrote:
>>
>>
>> On 4/13/2023 9:42 PM, Krzysztof Kozlowski wrote:
>>> On 13/04/2023 15:17, Bartosz Golaszewski wrote:
>>>> From: Parikshit Pareek <quic_ppareek@quicinc.com>
>>>>
>>>> Remove the power on reasons with reboot from the pmm8654au_0_pon.
>>>> Instead, the PoN reaons should be part of different sdam_0 mode, to
>>>
>>> typo: reasons
>>>
>>>> be interoduced.
>>>
>>> introduced
>>>
>>> Anyway it does not say why. Are these power reasons not correct?
>>>
>>
>> Hi Krzysztof,
>> Since sm8350 the PMIC PON peripheral was split into PON_HLOS and PON_PBS
>> to avoid security concerns with HLOS APPS being able to trigger a PMIC
>> WARM_RESET unilaterally. When the split occurred, the spare registers
>> ended up in PON_PBS, not PON_HLOS. Thus at that time, we moved to using
>> an SDAM register for Linux “reboot reason” configuration. And bootloader
>> also SDAM register to get these reboot region data to get into
>> bootloader/edl, so to have this working we need to use SDAM.
>>
> Does that imply all PMICs following the PMK8350 scheme (separate HLOS and
> PBS) should direct reboot mode writes to SDAM?
>
> Konrad

Yes, that's what the expectation is with bootloader using SDAM as well.

>>>>
>>>> Signed-off-by: Parikshit Pareek <quic_ppareek@quicinc.com>
>>>> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
>>>> ---
>>>
>>> Best regards,
>>> Krzysztof
>>>
>>
>> -Shazad

-Shazad