This allows much higher baudrates in the standard series to be used, up to 32 * 115200 = 3686400 bps with 0.16% deviation.
Signed-off-by: Matthijs van Duin matthijsvanduin@gmail.com --- drivers/serial/ns16550.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c index 41eb098c847e..a131d1658bd4 100644 --- a/drivers/serial/ns16550.c +++ b/drivers/serial/ns16550.c @@ -140,7 +140,11 @@ static u32 ns16550_getfcr(NS16550_t port)
int ns16550_calc_divisor(NS16550_t port, int clock, int baudrate) { +#ifdef UART_MDR1_13X + const unsigned int mode_x_div = 13; +#else const unsigned int mode_x_div = 16; +#endif
return DIV_ROUND_CLOSEST(clock, mode_x_div * baudrate); } @@ -181,9 +185,9 @@ void NS16550_init(NS16550_t com_port, int baud_divisor) serial_out(ns16550_getfcr(com_port), &com_port->fcr); if (baud_divisor != -1) NS16550_setbrg(com_port, baud_divisor); -#ifdef CONFIG_NS16550_OMAP - /* /16 is proper to hit 115200 with 48MHz */ - serial_out(UART_MDR1_16X, &com_port->mdr1); +#ifdef UART_MDR1_13X + /* /13 is proper to hit 115200*{1,2,4,8,16,32} with 48MHz */ + serial_out(UART_MDR1_13X, &com_port->mdr1); #endif #ifdef CONFIG_NS16550_C6X serial_out(UART_REG_VAL_PWREMU_MGMT_UART_ENABLE, &com_port->pwr_mgmt); @@ -297,7 +301,7 @@ static inline void _debug_uart_init(void) serial_dout(&com_port->dll, baud_divisor & 0xff); serial_dout(&com_port->dlm, (baud_divisor >> 8) & 0xff); serial_dout(&com_port->lcr, UART_LCRVAL); - serial_dout(&com_port->mdr1, UART_MDR1_16X); + serial_dout(&com_port->mdr1, UART_MDR1_13X); }
static inline void _debug_uart_putc(int ch)