[U-Boot-Users] [PATCH] ColdFire: Fix UART baudrate formula

[Kenneth Johansson]

On Thu, 2008-05-29 at 15:26 -0500, Tsi-Chung.Liew wrote:
> From: TsiChung Liew <Tsi-Chung.Liew at freescale.com>
> 
> The formula "counter = (u32) (gd->bus_clk / gd->baudrate) / 32"
> can generate the wrong divisor due to integer division truncation.
> Round the calculated divisor value by adding 1/2 the baudrate
> before dividing by the baudrate.
> 
> Signed-off-by: TsiChung Liew <Tsi-Chung.Liew at freescale.com>
> Acked-by: Gerald Van Baren <vanbaren at cideas.com>
> ---
>  drivers/serial/mcfuart.c |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/serial/mcfuart.c b/drivers/serial/mcfuart.c
> index 88f3eb1..75e85b7 100644
> --- a/drivers/serial/mcfuart.c
> +++ b/drivers/serial/mcfuart.c
> @@ -63,8 +63,8 @@ int serial_init(void)
>  	uart->umr = UART_UMR_SB_STOP_BITS_1;
>  
>  	/* Setting up BaudRate */
> -	counter = (u32) (gd->bus_clk / (gd->baudrate));
> -	counter >>= 5;
> +	counter = (u32) (gd->bus_clk / 32) + (gd->baudrate / 2));

And you compiled this ?? 

> +	counter = counter / gd->baudrate;
>  
>  	/* write to CTUR: divide counter upper byte */
>  	uart->ubg1 = (u8) ((counter & 0xff00) >> 8);