[PATCH 34.3 4/6] LEON3: debugputs added printk mem buffer when no UART present

[Joel Sherrill]

This looks OK.

As an aside, the new virtex BSPs have a console
driver which saves data in a buffer. The BSPs
were based on a configuration without a UART.
As a generic capability, that makes sense.

On 04/18/2012 10:19 AM, Daniel Hellstrom wrote:
> Signed-off-by: Daniel Hellstrom<daniel at gaisler.com>
> ---
>   c/src/lib/libbsp/sparc/leon3/console/debugputs.c |   14 +++++++++++++-
>   1 files changed, 13 insertions(+), 1 deletions(-)
>
> diff --git a/c/src/lib/libbsp/sparc/leon3/console/debugputs.c b/c/src/lib/libbsp/sparc/leon3/console/debugputs.c
> index 951218a..a189f5b 100644
> --- a/c/src/lib/libbsp/sparc/leon3/console/debugputs.c
> +++ b/c/src/lib/libbsp/sparc/leon3/console/debugputs.c
> @@ -33,6 +33,14 @@ static int isinit = 0;
>   int debug_uart_index __attribute__((weak)) = 0;
>   ambapp_apb_uart *dbg_uart = NULL;
>
> +/* Before UART driver has registered (or when no UART is available), calls to
> + * printk that gets to bsp_out_char() will be filling data into the
> + * pre_printk_dbgbuf[] buffer, hopefully the buffer can help debugging the
> + * early BSP boot.. At least the last printk() will be caught.
> + */
> +char pre_printk_dbgbuf[32] = {0};
> +int pre_printk_pos = 0;
> +
>   /* Initialize the BSP system debug console layer. It will scan AMBA Plu&Play
>    * for a debug APBUART and enable RX/TX for that UART.
>    */
> @@ -122,8 +130,12 @@ int apbuart_inbyte_nonblocking(ambapp_apb_uart *regs)
>   /* putchar/getchar for printk */
>   static void bsp_out_char(char c)
>   {
> -  if (dbg_uart == NULL)
> +  if (dbg_uart == NULL) {
> +    /* Local debug buffer when UART driver has not registered */
> +    pre_printk_dbgbuf[pre_printk_pos++] = c;
> +    pre_printk_pos = pre_printk_pos&  (sizeof(pre_printk_dbgbuf)-1);
>       return;
> +  }
>
>     apbuart_outbyte_polled(dbg_uart, c);
>   }


-- 
Joel Sherrill, Ph.D.             Director of Research&   Development
joel.sherrill at OARcorp.com        On-Line Applications Research
Ask me about RTEMS: a free RTOS  Huntsville AL 35805
     Support Available             (256) 722-9985