diff options
Diffstat (limited to 'drivers/serial/ns16550.c')
| -rw-r--r-- | drivers/serial/ns16550.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c index 8eeb48fb2a9..a44bd97ecb1 100644 --- a/drivers/serial/ns16550.c +++ b/drivers/serial/ns16550.c @@ -53,9 +53,22 @@ void NS16550_init (NS16550_t com_port, int baud_divisor) #endif /* CONFIG_OMAP */ } +#ifdef CONFIG_SERIAL_OUTPUT_FIFO +/* Flush transmit fifo and holding register */ +void NS16550_flush_tx_fifo(NS16550_t com_port) +{ + while ((serial_in(&com_port->lsr) & UART_LSR_TEMT) == 0) + ; +} +#endif + #ifndef CONFIG_NS16550_MIN_FUNCTIONS void NS16550_reinit (NS16550_t com_port, int baud_divisor) { +#ifdef CONFIG_SERIAL_OUTPUT_FIFO + /* flush output fifo before changing baudrate */ + NS16550_flush_tx_fifo(com_port); +#endif serial_out(CONFIG_SYS_NS16550_IER, &com_port->ier); serial_out(UART_LCR_BKSE | UART_LCRVAL, &com_port->lcr); serial_out(0, &com_port->dll); @@ -72,7 +85,13 @@ void NS16550_reinit (NS16550_t com_port, int baud_divisor) void NS16550_putc (NS16550_t com_port, char c) { +#ifdef CONFIG_SERIAL_OUTPUT_FIFO + /* Wait for some room in the fifo */ + while ((serial_in(&com_port->ssr) & UART_SSR_TX_FIFO_FULL)); +#else + /* Wait for Xmit holding register to be empty */ while ((serial_in(&com_port->lsr) & UART_LSR_THRE) == 0); +#endif serial_out(c, &com_port->thr); /* |