diff mbox series

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

Message ID 20230413131705.3073911-2-brgl@bgdev.pl
State Superseded
Headers show
Series arm64: qcom: fix the reboot reason handling on sa8775p | expand

Commit Message

Bartosz Golaszewski April 13, 2023, 1:17 p.m. UTC
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
be interoduced.

Signed-off-by: Parikshit Pareek <quic_ppareek@quicinc.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---
 arch/arm64/boot/dts/qcom/sa8775p-pmics.dtsi | 2 --
 1 file changed, 2 deletions(-)

Comments

Shazad Hussain April 18, 2023, 4:39 a.m. UTC | #1
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.

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

-Shazad
Krzysztof Kozlowski April 18, 2023, 7:04 a.m. UTC | #2
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.

The explanation of their correctness should be in commit msg.

Best regards,
Krzysztof
Konrad Dybcio April 18, 2023, 9:43 a.m. UTC | #3
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
>>>
>>> Signed-off-by: Parikshit Pareek <quic_ppareek@quicinc.com>
>>> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
>>> ---
>>
>> Best regards,
>> Krzysztof
>>
> 
> -Shazad
Shazad Hussain April 18, 2023, 9:54 a.m. UTC | #4
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
diff mbox series

Patch

diff --git a/arch/arm64/boot/dts/qcom/sa8775p-pmics.dtsi b/arch/arm64/boot/dts/qcom/sa8775p-pmics.dtsi
index 7602cca47bae..5abdc239d3a6 100644
--- a/arch/arm64/boot/dts/qcom/sa8775p-pmics.dtsi
+++ b/arch/arm64/boot/dts/qcom/sa8775p-pmics.dtsi
@@ -108,8 +108,6 @@  pmm8654au_0_pon: pon@1200 {
 			compatible = "qcom,pmk8350-pon";
 			reg = <0x1200>, <0x800>;
 			reg-names = "hlos", "pbs";
-			mode-recovery = <0x1>;
-			mode-bootloader = <0x2>;
 
 			pmm8654au_0_pon_pwrkey: pwrkey {
 				compatible = "qcom,pmk8350-pwrkey";