Re: [PATCH 1/2] arm64: dts: NS2: Add all of the UARTs

[Ray Jui <ray.jui@broadcom.com>]

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@huawei.com
> <mailto:wangkefeng.wang@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@broadcom.com <mailto:jonmason@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