[U-Boot-Users] [PATCH/review] Blackfin: make baud calculation more accurate

[Wolfgang Denk]

In message <1207721182-29697-1-git-send-email-vapier at gentoo.org> you wrote:
> We should use the algorithm in the Linux kernel so that the UART divisor
> calculation is more accurate.  It also fixes problems on some picky UARTs
> that have sampling anomalies.
> 
> Signed-off-by: Mike Frysinger <vapier at gentoo.org>
> ---
>  cpu/blackfin/serial.h |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/cpu/blackfin/serial.h b/cpu/blackfin/serial.h
> index 1f0f4b4..d268da5 100644
> --- a/cpu/blackfin/serial.h
> +++ b/cpu/blackfin/serial.h
> @@ -179,7 +179,7 @@ static inline void serial_early_set_baud(uint32_t baud)
>  	 * The +1 is to make sure we over sample just a little
^^^^^^^^^^^^^^^^^^^

Fix!

>  	 * rather than under sample the incoming signals.
>  	 */
> -	uint16_t divisor = (get_sclk() / (baud * 16)) + 1;
> +	uint16_t divisor = (get_sclk() + (baud * 8)) / (baud * 16);

Please make sure to adjust the comment, as there is no "+1" any more
in the new code.

Best regards,

Wolfgang Denk

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