[PATCH 1/2] arm64: dts: NS2: Add all of the UARTs
Ray Jui
ray.jui at broadcom.com
Thu May 12 09:52:31 PDT 2016
Hi Kefeng,
On 5/12/2016 7:46 AM, Jon Mason wrote:
>
>
> On Thu, May 12, 2016 at 2:16 AM, Kefeng Wang <wangkefeng.wang at huawei.com
> <mailto:wangkefeng.wang at huawei.com>> wrote:
>
>
>
> On 2016/5/12 6:56, Jon Mason wrote:
> > Add all of the UARTs present on NS2 and enable them in the SVK device
> > tree file. Also, do some magic to make sure that uart3 is discovered as
> > ttyS0 (as that is the console UART).
> >
> > Signed-off-by: Jon Mason <jonmason at broadcom.com <mailto:jonmason at broadcom.com>>
> > ---
> > arch/arm64/boot/dts/broadcom/ns2-svk.dts | 16 ++++++++++++++++
> > arch/arm64/boot/dts/broadcom/ns2.dtsi | 30 ++++++++++++++++++++++++++++++
> > 2 files changed, 46 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/broadcom/ns2-svk.dts b/arch/arm64/boot/dts/broadcom/ns2-svk.dts
> > index 7cd3640..b062a44 100644
> > --- a/arch/arm64/boot/dts/broadcom/ns2-svk.dts
> > +++ b/arch/arm64/boot/dts/broadcom/ns2-svk.dts
> > @@ -40,10 +40,14 @@
> >
> > aliases {
> > serial0 = &uart3;
> > + serial1 = &uart0;
> > + serial2 = &uart1;
> > + serial3 = &uart2;
> > };
> >
> > chosen {
> > stdout-path = "serial0:115200n8";
> > + bootargs = "earlycon=uart8250,mmio32,0x66130000";
>
> Hi Jon,
>
> I submit a patch[1], with it, we can use earlycon without option to
> enable early console
> for "snps,dw-apb-uart", could you help me to test it, thanks.
>
>
> Adding your change and removing the line above does not cause earlycon
> to work for me. Is there any additional changes necessary for this to work?
>
> Thanks,
> Jon
>
"OF_EARLYCON_DECLARE" doesn't seem to have a way to deal with DT
properties? In the case of UART for NS2, it needs mmio32, configured
with DT property "reg-io-width" set to 4. I don't think
"OF_EARLYCON_DECLARE" is parsing that, which is likely the reason why it
doesn't work for devices that required mmio32.
Thanks,
Ray
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