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

[Andrej Picej]

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@xxxxxxxxx>
> > > > > ---
> > > > >    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