diff options
Diffstat (limited to 'u-boot/drivers/serial/ns16550.c')
| -rw-r--r-- | u-boot/drivers/serial/ns16550.c | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/u-boot/drivers/serial/ns16550.c b/u-boot/drivers/serial/ns16550.c new file mode 100644 index 0000000..8eeb48f --- /dev/null +++ b/u-boot/drivers/serial/ns16550.c @@ -0,0 +1,106 @@ +/* + * COM1 NS16550 support + * originally from linux source (arch/powerpc/boot/ns16550.c) + * modified to use CONFIG_SYS_ISA_MEM and new defines + */ + +#include <config.h> +#include <ns16550.h> +#include <watchdog.h> +#include <linux/types.h> +#include <asm/io.h> + +#define UART_LCRVAL UART_LCR_8N1 /* 8 data, 1 stop, no parity */ +#define UART_MCRVAL (UART_MCR_DTR | \ + UART_MCR_RTS) /* RTS/DTR */ +#define UART_FCRVAL (UART_FCR_FIFO_EN | \ + UART_FCR_RXSR | \ + UART_FCR_TXSR) /* Clear & enable FIFOs */ +#ifdef CONFIG_SYS_NS16550_PORT_MAPPED +#define serial_out(x,y) outb(x,(ulong)y) +#define serial_in(y) inb((ulong)y) +#else +#define serial_out(x,y) writeb(x,y) +#define serial_in(y) readb(y) +#endif + +#ifndef CONFIG_SYS_NS16550_IER +#define CONFIG_SYS_NS16550_IER 0x00 +#endif /* CONFIG_SYS_NS16550_IER */ + +void NS16550_init (NS16550_t com_port, int baud_divisor) +{ + serial_out(CONFIG_SYS_NS16550_IER, &com_port->ier); +#if defined(CONFIG_OMAP) && !defined(CONFIG_OMAP3_ZOOM2) + serial_out(0x7, &com_port->mdr1); /* mode select reset TL16C750*/ +#endif + serial_out(UART_LCR_BKSE | UART_LCRVAL, (ulong)&com_port->lcr); + serial_out(0, &com_port->dll); + serial_out(0, &com_port->dlm); + serial_out(UART_LCRVAL, &com_port->lcr); + serial_out(UART_MCRVAL, &com_port->mcr); + serial_out(UART_FCRVAL, &com_port->fcr); + serial_out(UART_LCR_BKSE | UART_LCRVAL, &com_port->lcr); + serial_out(baud_divisor & 0xff, &com_port->dll); + serial_out((baud_divisor >> 8) & 0xff, &com_port->dlm); + serial_out(UART_LCRVAL, &com_port->lcr); +#if defined(CONFIG_OMAP) && !defined(CONFIG_OMAP3_ZOOM2) +#if defined(CONFIG_APTIX) + serial_out(3, &com_port->mdr1); /* /13 mode so Aptix 6MHz can hit 115200 */ +#else + serial_out(0, &com_port->mdr1); /* /16 is proper to hit 115200 with 48MHz */ +#endif +#endif /* CONFIG_OMAP */ +} + +#ifndef CONFIG_NS16550_MIN_FUNCTIONS +void NS16550_reinit (NS16550_t com_port, int baud_divisor) +{ + 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); + serial_out(0, &com_port->dlm); + serial_out(UART_LCRVAL, &com_port->lcr); + serial_out(UART_MCRVAL, &com_port->mcr); + serial_out(UART_FCRVAL, &com_port->fcr); + serial_out(UART_LCR_BKSE, &com_port->lcr); + serial_out(baud_divisor & 0xff, &com_port->dll); + serial_out((baud_divisor >> 8) & 0xff, &com_port->dlm); + serial_out(UART_LCRVAL, &com_port->lcr); +} +#endif /* CONFIG_NS16550_MIN_FUNCTIONS */ + +void NS16550_putc (NS16550_t com_port, char c) +{ + while ((serial_in(&com_port->lsr) & UART_LSR_THRE) == 0); + serial_out(c, &com_port->thr); + + /* + * Call watchdog_reset() upon newline. This is done here in putc + * since the environment code uses a single puts() to print the complete + * environment upon "printenv". So we can't put this watchdog call + * in puts(). + */ + if (c == '\n') + WATCHDOG_RESET(); +} + +#ifndef CONFIG_NS16550_MIN_FUNCTIONS +char NS16550_getc (NS16550_t com_port) +{ + while ((serial_in(&com_port->lsr) & UART_LSR_DR) == 0) { +#ifdef CONFIG_USB_TTY + extern void usbtty_poll(void); + usbtty_poll(); +#endif + WATCHDOG_RESET(); + } + return serial_in(&com_port->rbr); +} + +int NS16550_tstc (NS16550_t com_port) +{ + return ((serial_in(&com_port->lsr) & UART_LSR_DR) != 0); +} + +#endif /* CONFIG_NS16550_MIN_FUNCTIONS */ |