[U-Boot] [PATCH 2/2] rockchip: rk3399: rockpro64: enable force power on reset workaround

[Vasily Khoruzhick]

On Thu, Nov 28, 2019 at 1:23 AM Kever Yang <kever.yang at rock-chips.com> wrote:
>
> Hi Vasily,
>
>      I think this should not be needed, see comments below.

Hi Kever,

I've spent 2 weeks of my evenings debugging this issue but
unfortunately I don't have a proper fix. This is the only solution
that makes my rockpro64 reboot reliably with mainline u-boot and ATF.
See my comments below.

> Hi Philipp, Klaus and Christoph:
>
>      Could you help to check why do you need below patch for your board?
>
> ae0d33a729 rockchip: rk3399-puma: add code to allow forcing a power-on reset
>
>
>      I think we don't need this workaround for rk3399 CPU_B voltage
> supply, and
> here is what I got:
> - rockchip use cru glb_rst_1 for reboot in kernel;
> - the glb_rst_1 will reset all the GPIO logic to default state;
> - the cpu_b voltage supplier syr83x have a VSEL connect to rk3399, which
> may be
>     a pull up/down IO,
> - the syr83x output with the hardware default state of the VSEL(with
> RK3399 default IO output)
>    should be normal output(1.0V), and another state output for
> suspend(disabled),
> - In order to make the syr83x works as expected, the kernel setting of
> syr83x should be correct,
>    check property:
>      fcs,suspend-voltage-selector = <1>;
>     This is correct for rockpro64(vsel connect to a gpio with default
> pull down) on upstream,
>      but I don't have a puma schematic, so I don't know if this is
> correct for puma.
> - With correct setting in syr83x, the cpu_b should always have power
> supply after reboot/reset with
>    cru glb_rst_1 reg.
> So no workaround is needed in U-Boot, please correct me if anything is
> missing.

I already tried re-initializing SYR83x, see [1] (and thus fixed couple
of the bugs in FAN53555 driver which has been broken since it was
merged into u-boot) but it doesn't help with reboot issue on
RockPro64. I checked VSEL gpio status and it's identical on cold boot
and on soft reboot, so I doubt SYR83X settings are related since I
checked regulators settings and they're correct.

I tried to boot with CPUFREQ disabled - that didn't help, linux hangs
when booted after soft reset.

Also tried to boot with big cluster disabled - that didn't help either.

So could you merge this patch please unless someone else wants to work
on this issue?

Thanks,
Vasily.

[1] https://github.com/anarsoul/u-boot-pine64/commit/7a50e58f09c68efe08f0b9912805fb9b3c985751

> Thanks,
> - Kever
> On 2019/11/28 下午2:14, Vasily Khoruzhick wrote:
> > Rockpro64 doesn't boot reliably after soft reset, so let's force power on
> > reset by asserting sysreset pin if we detected soft reset.
> >
> > Signed-off-by: Vasily Khoruzhick <anarsoul at gmail.com>
> > ---
> >   arch/arm/dts/rk3399-rockpro64-u-boot.dtsi | 8 ++++++++
> >   configs/rockpro64-rk3399_defconfig        | 1 +
> >   2 files changed, 9 insertions(+)
> >
> > diff --git a/arch/arm/dts/rk3399-rockpro64-u-boot.dtsi b/arch/arm/dts/rk3399-rockpro64-u-boot.dtsi
> > index 4648513ea9..bb94bcf7be 100644
> > --- a/arch/arm/dts/rk3399-rockpro64-u-boot.dtsi
> > +++ b/arch/arm/dts/rk3399-rockpro64-u-boot.dtsi
> > @@ -6,11 +6,19 @@
> >   #include "rk3399-u-boot.dtsi"
> >   #include "rk3399-sdram-lpddr4-100.dtsi"
> >   / {
> > +     config {
> > +             sysreset-gpio = <&gpio1 RK_PA6 GPIO_ACTIVE_HIGH>;
> > +     };
> > +
> >       chosen {
> >               u-boot,spl-boot-order = "same-as-spl", &sdmmc, &sdhci;
> >       };
> >   };
> >
> > +&gpio1  {
> > +     u-boot,dm-pre-reloc;
> > +};
> > +
> >   &vdd_center {
> >       regulator-min-microvolt = <950000>;
> >       regulator-max-microvolt = <950000>;
> > diff --git a/configs/rockpro64-rk3399_defconfig b/configs/rockpro64-rk3399_defconfig
> > index 49e27c91cb..d153ac5485 100644
> > --- a/configs/rockpro64-rk3399_defconfig
> > +++ b/configs/rockpro64-rk3399_defconfig
> > @@ -1,6 +1,7 @@
> >   CONFIG_ARM=y
> >   CONFIG_ARCH_ROCKCHIP=y
> >   CONFIG_SYS_TEXT_BASE=0x00200000
> > +CONFIG_SPL_GPIO_SUPPORT=y
> >   CONFIG_ROCKCHIP_RK3399=y
> >   CONFIG_ENV_OFFSET=0x3F8000
> >   CONFIG_TARGET_ROCKPRO64_RK3399=y
>
>