From fa54eb12431efa845bc5692347ee3a7f39d897bc Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Thu, 4 Sep 2014 16:27:32 -0600 Subject: [PATCH] dm: serial: Move baud rate calculation to ns16550.c Move the function that calculates the baud rate divisor into ns16550.c so it can be used by that file. Signed-off-by: Simon Glass --- drivers/serial/ns16550.c | 18 +++++++++++++++++- drivers/serial/serial_ns16550.c | 14 ++++---------- include/ns16550.h | 13 +++++++++++++ 3 files changed, 34 insertions(+), 11 deletions(-) diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c index 079f67d380..3f5f4efe07 100644 --- a/drivers/serial/ns16550.c +++ b/drivers/serial/ns16550.c @@ -4,7 +4,7 @@ * modified to use CONFIG_SYS_ISA_MEM and new defines */ -#include +#include #include #include #include @@ -45,6 +45,22 @@ #define CONFIG_SYS_NS16550_IER 0x00 #endif /* CONFIG_SYS_NS16550_IER */ +int ns16550_calc_divisor(NS16550_t port, int clock, int baudrate) +{ + const unsigned int mode_x_div = 16; + +#ifdef CONFIG_OMAP1510 + /* If can't cleanly clock 115200 set div to 1 */ + if ((clock == 12000000) && (baudrate == 115200)) { + port->osc_12m_sel = OSC_12M_SEL; /* enable 6.5 * divisor */ + return 1; /* return 1 for base divisor */ + } + port->osc_12m_sel = 0; /* clear if previsouly set */ +#endif + + return DIV_ROUND_CLOSEST(clock, mode_x_div * baudrate); +} + void NS16550_init(NS16550_t com_port, int baud_divisor) { #if (defined(CONFIG_SPL_BUILD) && defined(CONFIG_OMAP34XX)) diff --git a/drivers/serial/serial_ns16550.c b/drivers/serial/serial_ns16550.c index dafeed742d..632da4cf70 100644 --- a/drivers/serial/serial_ns16550.c +++ b/drivers/serial/serial_ns16550.c @@ -81,7 +81,8 @@ static NS16550_t serial_ports[6] = { static int eserial##port##_init(void) \ { \ int clock_divisor; \ - clock_divisor = calc_divisor(serial_ports[port-1]); \ + clock_divisor = ns16550_calc_divisor(serial_ports[port-1], \ + CONFIG_SYS_NS16550_CLK, gd->baudrate); \ NS16550_init(serial_ports[port-1], clock_divisor); \ return 0 ; \ } \ @@ -118,14 +119,6 @@ static NS16550_t serial_ports[6] = { .puts = eserial##port##_puts, \ } -static int calc_divisor (NS16550_t port) -{ - const unsigned int mode_x_div = 16; - - return DIV_ROUND_CLOSEST(CONFIG_SYS_NS16550_CLK, - mode_x_div * gd->baudrate); -} - void _serial_putc(const char c,const int port) { @@ -167,7 +160,8 @@ _serial_setbrg (const int port) { int clock_divisor; - clock_divisor = calc_divisor(PORT); + clock_divisor = ns16550_calc_divisor(PORT, CONFIG_SYS_NS16550_CLK, + gd->baudrate); NS16550_reinit(PORT, clock_divisor); } diff --git a/include/ns16550.h b/include/ns16550.h index d1f3a906c0..d93e28e3ec 100644 --- a/include/ns16550.h +++ b/include/ns16550.h @@ -170,3 +170,16 @@ void NS16550_putc(NS16550_t com_port, char c); char NS16550_getc(NS16550_t com_port); int NS16550_tstc(NS16550_t com_port); void NS16550_reinit(NS16550_t com_port, int baud_divisor); + +/** + * ns16550_calc_divisor() - calculate the divisor given clock and baud rate + * + * Given the UART input clock and required baudrate, calculate the divisor + * that should be used. + * + * @port: UART port + * @clock: UART input clock speed in Hz + * @baudrate: Required baud rate + * @return baud rate divisor that should be used + */ +int ns16550_calc_divisor(NS16550_t port, int clock, int baudrate); -- 2.25.1