Subversion Repositories openrisc

#include "board.h"
#include "uart.h"
 
#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
 
#define WAIT_FOR_XMITR \
        do { \
                lsr = REG8(UART_BASE + UART_LSR); \
        } while ((lsr & BOTH_EMPTY) != BOTH_EMPTY)
 
#define WAIT_FOR_THRE \
        do { \
                lsr = REG8(UART_BASE + UART_LSR); \
        } while ((lsr & UART_LSR_THRE) != UART_LSR_THRE)
 
#define CHECK_FOR_CHAR (REG8(UART_BASE + UART_LSR) & UART_LSR_DR)
 
#define WAIT_FOR_CHAR \
         do { \
                lsr = REG8(UART_BASE + UART_LSR); \
         } while ((lsr & UART_LSR_DR) != UART_LSR_DR)
 
void uart_init(void)
{
	int divisor;
 
	/* Reset receiver and transmiter */
	REG8(UART_BASE + UART_FCR) = UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT | UART_FCR_TRIGGER_14;
 
	/* Disable all interrupts */
	REG8(UART_BASE + UART_IER) = 0x00;
 
	/* Set 8 bit char, 1 stop bit, no parity */
	REG8(UART_BASE + UART_LCR) = UART_LCR_WLEN8 & ~(UART_LCR_STOP | UART_LCR_PARITY);
 
	/* Set baud rate */
	divisor = IN_CLK/(16 * UART_BAUD_RATE);
	REG8(UART_BASE + UART_LCR) |= UART_LCR_DLAB;
	REG8(UART_BASE + UART_DLL) = divisor & 0x000000ff;
	REG8(UART_BASE + UART_DLM) = (divisor >> 8) & 0x000000ff;
	REG8(UART_BASE + UART_LCR) &= ~(UART_LCR_DLAB);
}
 
void uart_putc(char c)
{
	unsigned char lsr;
 
	WAIT_FOR_THRE;
	REG8(UART_BASE + UART_TX) = c;
	if(c == '\n') {
		WAIT_FOR_THRE;
		REG8(UART_BASE + UART_TX) = '\r';
	}
	WAIT_FOR_XMITR;
}
 
char uart_getc(void)
{
  	  unsigned char lsr;
  	  char c;
 
  	  WAIT_FOR_CHAR;
  	  c = REG8(UART_BASE + UART_RX);
 
  	  return c;
}