[U-Boot] [PATCH v3] serial: Add serial driver for Intel MID

[Simon Glass]

On 28 February 2017 at 05:04, Andy Shevchenko
<andriy.shevchenko at linux.intel.com> wrote:
> Add a specific serial driver for Intel MID platforms.
>
> It has special fractional divider which can be programmed via UART_PS,
> UART_MUL, and UART_DIV registers.
>
> The UART clock is calculated as
>
>         UART clock = XTAL * UART_MUL / UART_DIV
>
> The baudrate is calculated as
>
>         baud rate = UART clock / UART_PS / DLAB
>
> Initialize fractional divider correctly for Intel Edison platform.
>
> For backward compatibility we have to set initial DLAB value to 16
> and speed to 115200 baud, where initial frequency is 29491200Hz, and
> XTAL frequency is 38.4MHz.
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko at linux.intel.com>
> ---
>  drivers/serial/Kconfig            |  9 +++++
>  drivers/serial/Makefile           |  1 +
>  drivers/serial/serial_intel_mid.c | 69 +++++++++++++++++++++++++++++++++++++++
>  3 files changed, 79 insertions(+)
>  create mode 100644 drivers/serial/serial_intel_mid.c

Reviewed-by: Simon Glass <sjg at chromium.org>