Re: [PATCH] arm64: rockchip: enable Rockchip IO domain support

[Heiko Stübner]

Am Freitag, 15. Dezember 2017, 16:51:39 CET schrieb klaus.goger@theobroma-
systems.com:
> > On 15.12.2017, at 16:33, Heiko StÃbner <heiko@xxxxxxxxx> wrote:
> > 
> > Am Freitag, 15. Dezember 2017, 13:20:10 CET schrieb Klaus Goger:
> >> Make sure the IO domain support is active. This requires to enable
> >> Adaptive Voltage Scaling class support too.
> >> 
> >> Without Rockchip IO domain support the internal level shifter on the
> >> RK3399
> >> will be misconfigured if used in the other voltage domain then the
> >> default.
> >> 
> >> Signed-off-by: Klaus Goger <klaus.goger@xxxxxxxxxxxxxxxxxxxxx>
> >> 
> >> ---
> >> 
> >> arch/arm64/Kconfig.platforms | 2 ++
> >> 1 file changed, 2 insertions(+)
> >> 
> >> diff --git a/arch/arm64/Kconfig.platforms b/arch/arm64/Kconfig.platforms
> >> index 2401373565ff..7c0b0ab12f18 100644
> >> --- a/arch/arm64/Kconfig.platforms
> >> +++ b/arch/arm64/Kconfig.platforms
> >> @@ -150,6 +150,8 @@ config ARCH_ROCKCHIP
> >> 
> >> 	select GPIOLIB
> >> 	select PINCTRL
> >> 	select PINCTRL_ROCKCHIP
> >> 
> >> +	select POWER_AVS
> >> +	select ROCKCHIP_IODOMAIN
> > 
> > I'm not sure if we really want this in the default arch Kconfig or if
> > there
> > are cases where the iodomain driver is not necessary.
> > 
> > On arm32 it just gets selected in the regular defconfig [0]
> 
> At least all currently supported 64bit Rockchip SoCs do have matching VSEL
> GRF settings. For me it looked essential enough to enable for all as not
> setting the correct I/O voltage will result in no output signal at all.
> But Iâm fine with a defconfig change if thatâs the way to go.
> Should I resend a patch or wait for other opinions?

Personally I would go with a defconfig change. I'd really like to keep the 
kconfig stuff minimal and at least all arm64 Rockchip boards can at least
boot without the iodomain driver.


Heiko