linux-kernel - Re: [PATCH 2/2] ARM: dts: imx6: pfla02: Fix SD card reboot problem

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <6a2e5b14-c5d3-b384-2539-033381768dca@norik.com>
Date:   Wed, 5 Jul 2023 12:39:20 +0200
From:   Andrej Picej <andrej.picej@...ik.com>
To:     Ahmad Fatoum <a.fatoum@...gutronix.de>,
        Marco Felsch <m.felsch@...gutronix.de>
Cc:     devicetree@...r.kernel.org, conor+dt@...nel.org,
        krzysztof.kozlowski+dt@...aro.org, festevam@...il.com,
        s.hauer@...gutronix.de, linux-kernel@...r.kernel.org,
        robh+dt@...nel.org, linux-imx@....com, kernel@...gutronix.de,
        shawnguo@...nel.org, linux-arm-kernel@...ts.infradead.org,
        upstream@...tec.de
Subject: Re: [PATCH 2/2] ARM: dts: imx6: pfla02: Fix SD card reboot problem


On 5. 07. 23 10:40, Andrej Picej wrote:
> 
> 
> On 5. 07. 23 10:30, Ahmad Fatoum wrote:
>> On 05.07.23 10:28, Andrej Picej wrote:
>>> Hi Marco,
>>>
>>> On 4. 07. 23 10:17, Marco Felsch wrote:
>>>> On 23-07-04, Andrej Picej wrote:
>>>>> If regulator is not marked as always-on the regulator gets disabled on
>>>>> reboot breaking the next boot.
>>>>>
>>>>> Signed-off-by: Andrej Picej <andrej.picej@...ik.com>
>>>>> ---
>>>>>    arch/arm/boot/dts/imx6qdl-phytec-pfla02.dtsi | 1 +
>>>>>    1 file changed, 1 insertion(+)
>>>>>
>>>>> diff --git a/arch/arm/boot/dts/imx6qdl-phytec-pfla02.dtsi 
>>>>> b/arch/arm/boot/dts/imx6qdl-phytec-pfla02.dtsi
>>>>> index 80adb2a02cc9..25d6a036d5b8 100644
>>>>> --- a/arch/arm/boot/dts/imx6qdl-phytec-pfla02.dtsi
>>>>> +++ b/arch/arm/boot/dts/imx6qdl-phytec-pfla02.dtsi
>>>>> @@ -192,6 +192,7 @@ vdd_3v3_pmic_io_reg: ldo6 {
>>>>>                vdd_sd0_reg: ldo9 {
>>>>>                    regulator-min-microvolt = <3300000>;
>>>>>                    regulator-max-microvolt = <3300000>;
>>>>> +                regulator-always-on;
>>>>
>>>> I think this is the supply for the sd-card, so you can make use of
>>>> 'vmmc-supply'.
>>>
>>> This is already the case:
>>>
>>>> &usdhc3 {
>>>>      pinctrl-names = "default";
>>>>      pinctrl-0 = <&pinctrl_usdhc3
>>>>               &pinctrl_usdhc3_cdwp>;
>>>>      cd-gpios = <&gpio1 27 GPIO_ACTIVE_LOW>;
>>>>      wp-gpios = <&gpio1 29 GPIO_ACTIVE_HIGH>;
>>>>      vmmc-supply = <&vdd_sd0_reg>;
>>>>      status = "disabled";
>>>> };
>>>
>>> I think the main reason for a failed boot is that the PMIC doesn't 
>>> get reset and that the bootloader doesn't specifically enable the SD 
>>> card regulator.
>>>
>>> Could this patch still be applied or should we put the fix in reset 
>>> routine/bootloader?
>>
>> Is SD-Card not main boot medium? From your description, I thought BootROM
>> will fail to boot before bootloader has a chance to do anything about it.
>>
> 
> Yes sorry, you are absolutly right, the BootROM fails. It confused me 
> because I could see the booloader booting, but it was from one of the 
> fallback mediums. So I guess fixing the bootloader is not really an option.
> Sorry for the confusion.
> 

Ok, the main problem is well known, that's why PHYTEC disables the imx 
watchdog and uses a PMIC one for the reboot handler. This one resets the 
board completely. The SD card regulator problem is really just the 
manifestation of that bug. Unfortunately I didn't noticed that. :(

I will create a v2 with a proper fix, where imx watchdog gets disabled.

Thanks for your help,
Andrej


> 
>>>
>>> Best regards,
>>> Andrej
>>>
>>>>
>>>> Regards,
>>>>     Marco
>>>>
>>>>>                };
>>>>>                  vdd_sd1_reg: ldo10 {
>>>>> -- 
>>>>> 2.25.1
>>>>>
>>>>>
>>>>>
>>>
>>>
>>