[U-Boot] [PATCH v2 3/5] debug_uart: Add an option to announce the debug UART

[Bin Meng]

On Mon, Oct 19, 2015 at 9:51 AM, Simon Glass <sjg at chromium.org> wrote:
> It is useful to see a message from the debug UART early during boot so that
> you know things are working. Add an option to enable this. The message will
> be displayed as soon as debug_uart_init() is called.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
> Changes in v2: None
>
>  drivers/serial/Kconfig | 10 ++++++++++
>  include/debug_uart.h   |  7 +++++++
>  2 files changed, 17 insertions(+)
>
> diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
> index 39f6500..ac5920a 100644
> --- a/drivers/serial/Kconfig
> +++ b/drivers/serial/Kconfig
> @@ -120,6 +120,16 @@ config DEBUG_UART_BOARD_INIT
>           here that is needed to set up the UART ready for use, such as set
>           pin multiplexing or enable clocks.
>
> +config DEBUG_UART_ANNOUNCE
> +       bool "Show a message when the debug UART starts up"
> +       depends on DEBUG_UART
> +       help
> +         Enable this option to show a message when the debug UART is ready
> +         for use. You will see a message like "<debug_uart> " as soon as
> +         U-Boot has the UART ready for use (i.e. your code calls
> +         debug_uart_init()). This can be useful just as a check that
> +         everything is working.
> +
>  config ROCKCHIP_SERIAL
>         bool "Rockchip on-chip UART support"
>         depends on ARCH_ROCKCHIP && DM_SERIAL
> diff --git a/include/debug_uart.h b/include/debug_uart.h
> index a6b7ce8..5d5349b 100644
> --- a/include/debug_uart.h
> +++ b/include/debug_uart.h
> @@ -105,6 +105,12 @@ void printhex4(uint value);
>   */
>  void printhex8(uint value);
>
> +#ifdef CONFIG_DEBUG_UART_ANNOUNCE
> +#define _DEBUG_UART_ANNOUNCE   printascii("<debug_uart> ");
> +#else
> +#define _DEBUG_UART_ANNOUNCE
> +#endif
> +
>  /*
>   * Now define some functions - this should be inserted into the serial driver
>   */
> @@ -151,6 +157,7 @@ void printhex8(uint value);
>         { \
>                 board_debug_uart_init(); \
>                 _debug_uart_init(); \
> +               _DEBUG_UART_ANNOUNCE \
>         } \
>
>  #endif
> --

Reviewed-by: Bin Meng <bmeng.cn at gmail.com>