[PATCH v2 1/2] arm64: dts: mt8173: Set uart to mmio32 iotype

Hsin-Yi Wang hsinyi at chromium.org
Fri Sep 11 05:43:06 EDT 2020


On Thu, Sep 10, 2020 at 9:40 PM Hsin-Yi Wang <hsinyi at chromium.org> wrote:
>
> On Thu, Sep 10, 2020 at 6:25 PM Matthias Brugger <matthias.bgg at gmail.com> wrote:
> >
> > Hi,
> >
> > On 10/09/2020 10:43, Hsin-Yi Wang wrote:
> > > Set uart iotype to mmio32 to make earlycon work with stdout-path.
> > >
> > > Signed-off-by: Hsin-Yi Wang <hsinyi at chromium.org>
> > > ---
> > >   arch/arm64/boot/dts/mediatek/mt8173.dtsi | 8 ++++++++
> > >   1 file changed, 8 insertions(+)
> > >
> > > diff --git a/arch/arm64/boot/dts/mediatek/mt8173.dtsi b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> > > index 5e046f9d48ce9..ca6ea71f5f435 100644
> > > --- a/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> > > +++ b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> > > @@ -613,6 +613,8 @@ uart0: serial at 11002000 {
> > >                       interrupts = <GIC_SPI 83 IRQ_TYPE_LEVEL_LOW>;
> > >                       clocks = <&pericfg CLK_PERI_UART0_SEL>, <&pericfg CLK_PERI_UART0>;
> > >                       clock-names = "baud", "bus";
> > > +                     reg-io-width = <4>;
> >
> > Why do we need that, we have
> > device->port.iotype = UPIO_MEM32;
> > in early_mtk8250_setup(). That should do the job already.
> >
> >
>
> But if we don't change in dts, we would see
> [    0.000000] earlycon: mtk8250 at MMIO 0x0000000011002000 (options '115200n8')
> instead of
> [    0.000000] earlycon: mtk8250 at MMIO32 0x0000000011002000 (options
> '115200n8')
>
> Perhaps we should move the pr_info part in earlycon_init() after
> match->setup(). Since setup may change iotype. What do you think?
>

The series is sent here: https://lore.kernel.org/patchwork/patch/1304227/

Thanks.



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