diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/serial/Kconfig | 13 | ||||
| -rw-r--r-- | drivers/serial/ns16550.c | 50 |
2 files changed, 61 insertions, 2 deletions
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index 6313258eac..1686a1f951 100644 --- a/drivers/serial/Kconfig +++ b/drivers/serial/Kconfig @@ -33,6 +33,19 @@ config DEBUG_UART serial drivers are up and running (done in serial_init()). Otherwise the drivers may conflict and you will get strange output. +choice + prompt "Select which UART will provide the debug UART" + depends on DEBUG_UART + +config DEBUG_UART_NS16550 + bool "ns16550" + help + Select this to enable a debug UART using the ns16550 driver. You + will need to provide parameters to make this work. The driver will + be available until the real driver model serial is running. + +endchoice + config DEBUG_UART_BASE hex "Base address of UART" depends on DEBUG_UART diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c index 57e6125de2..eb00f1ca8a 100644 --- a/drivers/serial/ns16550.c +++ b/drivers/serial/ns16550.c @@ -118,10 +118,15 @@ static int ns16550_readb(NS16550_t port, int offset) ns16550_readb(com_port, addr - (unsigned char *)com_port) #endif -int ns16550_calc_divisor(NS16550_t port, int clock, int baudrate) +static inline int calc_divisor(NS16550_t port, int clock, int baudrate) { const unsigned int mode_x_div = 16; + return DIV_ROUND_CLOSEST(clock, mode_x_div * baudrate); +} + +int ns16550_calc_divisor(NS16550_t port, int clock, int baudrate) +{ #ifdef CONFIG_OMAP1510 /* If can't cleanly clock 115200 set div to 1 */ if ((clock == 12000000) && (baudrate == 115200)) { @@ -131,7 +136,7 @@ int ns16550_calc_divisor(NS16550_t port, int clock, int baudrate) port->osc_12m_sel = 0; /* clear if previsouly set */ #endif - return DIV_ROUND_CLOSEST(clock, mode_x_div * baudrate); + return calc_divisor(port, clock, baudrate); } static void NS16550_setbrg(NS16550_t com_port, int baud_divisor) @@ -231,6 +236,47 @@ int NS16550_tstc(NS16550_t com_port) #endif /* CONFIG_NS16550_MIN_FUNCTIONS */ +#ifdef CONFIG_DEBUG_UART_NS16550 + +#include <debug_uart.h> + +void debug_uart_init(void) +{ + struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE; + int baud_divisor; + + /* + * We copy the code from above because it is already horribly messy. + * Trying to refactor to nicely remove the duplication doesn't seem + * feasible. The better fix is to move all users of this driver to + * driver model. + */ + baud_divisor = calc_divisor(com_port, CONFIG_DEBUG_UART_CLOCK, + CONFIG_BAUDRATE); + + serial_out_shift(&com_port->ier, 0, CONFIG_SYS_NS16550_IER); + serial_out_shift(&com_port->mcr, 0, UART_MCRVAL); + serial_out_shift(&com_port->fcr, 0, UART_FCRVAL); + + serial_out_shift(&com_port->lcr, 0, UART_LCR_BKSE | UART_LCRVAL); + serial_out_shift(&com_port->dll, 0, baud_divisor & 0xff); + serial_out_shift(&com_port->dlm, 0, (baud_divisor >> 8) & 0xff); + serial_out_shift(&com_port->lcr, 0, UART_LCRVAL); +} + +static inline void _debug_uart_putc(int ch) +{ + struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE; + + while (!(serial_in_shift(&com_port->lsr, 0) & UART_LSR_THRE)) + ; + serial_out_shift(&com_port->thr, 0, ch); +} + +DEBUG_UART_FUNCS + +#endif + #ifdef CONFIG_DM_SERIAL static int ns16550_serial_putc(struct udevice *dev, const char ch) { |
