Re: [PATCH 4/4] arm: mediatek: Add earlyprintk support for MT6589

[Rob Herring <robherring2@gmail.com>]

On Wed, Apr 9, 2014 at 2:45 PM, Matthias Brugger <matthias.bgg@gmail.com> wrote:
> Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
> ---
>  arch/arm/Kconfig.debug            |   49 +++++++++++++++++++++++++++++++++++--
>  arch/arm/include/debug/mediatek.S |   38 ++++++++++++++++++++++++++++
>  2 files changed, 85 insertions(+), 2 deletions(-)
>  create mode 100644 arch/arm/include/debug/mediatek.S
>
> diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
> index 4a2fc0b..dc51495 100644
> --- a/arch/arm/Kconfig.debug
> +++ b/arch/arm/Kconfig.debug
> @@ -797,6 +797,38 @@ choice
>                   Say Y here if you want kernel low-level debugging support
>                   on Ux500 based platforms.
>
> +       config DEBUG_MTK6589_UART0
> +               depends on ARCH_MEDIATEK
> +               bool "Mediatek mt6589 UART0"
> +               select DEBUG_UART_MEDIATEK
> +               help
> +                 Say Y here if you want kernel low-level debugging support
> +                 on Mediatek mt6589 based platforms.
> +
> +       config DEBUG_MTK6589_UART1
> +               depends on ARCH_MEDIATEK
> +               bool "Mediatek mt6589 UART1"
> +               select DEBUG_UART_MEDIATEK
> +               help
> +                 Say Y here if you want kernel low-level debugging support
> +                 on Mediatek mt6589 based platforms.
> +
> +       config DEBUG_MTK6589_UART2
> +               depends on ARCH_MEDIATEK
> +               bool "Mediatek mt6589 UART2"
> +               select DEBUG_UART_MEDIATEK
> +               help
> +                 Say Y here if you want kernel low-level debugging support
> +                 on Mediatek mt6589 based platforms.
> +
> +       config DEBUG_MTK6589_UART3
> +               depends on ARCH_MEDIATEK
> +               bool "Mediatek mt6589 UART3"
> +               select DEBUG_UART_MEDIATEK
> +               help
> +                 Say Y here if you want kernel low-level debugging support
> +                 on Mediatek mt6589 based platforms.
> +

Do you really need all uarts defined? Only define what you have boards using.

Also, you have no uarts defined in your dts. Please add them there
(and any necessary serial driver) before adding debug functionality.
Otherwise, you can't actually boot a multi-platform kernel with this
series.