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/*
* Copyright (C) 2001 MontaVista Software Inc.
* Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
*/
#include "uart16550.h"
/* === CONFIG === */
#define BASE 0xb8058000
#define MAX_BAUD 1152000
#define REG_OFFSET 4
/* === END OF CONFIG === */
/* register offset */
#define OFS_RCV_BUFFER (0*REG_OFFSET)
#define OFS_TRANS_HOLD (0*REG_OFFSET)
#define OFS_SEND_BUFFER (0*REG_OFFSET)
#define OFS_INTR_ENABLE (1*REG_OFFSET)
#define OFS_INTR_ID (2*REG_OFFSET)
#define OFS_DATA_FORMAT (3*REG_OFFSET)
#define OFS_LINE_CONTROL (3*REG_OFFSET)
#define OFS_MODEM_CONTROL (4*REG_OFFSET)
#define OFS_RS232_OUTPUT (4*REG_OFFSET)
#define OFS_LINE_STATUS (5*REG_OFFSET)
#define OFS_MODEM_STATUS (6*REG_OFFSET)
#define OFS_RS232_INPUT (6*REG_OFFSET)
#define OFS_SCRATCH_PAD (7*REG_OFFSET)
#define OFS_DIVISOR_LSB (0*REG_OFFSET)
#define OFS_DIVISOR_MSB (1*REG_OFFSET)
/* memory-mapped read/write of the port */
#define UART16550_READ(y) (*((volatile uint32*)(BASE + y)))
#define UART16550_WRITE(y, z) ((*((volatile uint32*)(BASE + y))) = z)
#define DEBUG_LED (*(unsigned short*)0xb7ffffc0)
#define OutputLED(x) (DEBUG_LED = x)
void Uart16550Init(uint32 baud, uint8 data, uint8 parity, uint8 stop)
{
/* disable interrupts */
UART16550_WRITE(OFS_INTR_ENABLE, 0);
/* set up buad rate */
{
uint32 divisor;
/* set DIAB bit */
UART16550_WRITE(OFS_LINE_CONTROL, 0x80);
/* set divisor */
divisor = MAX_BAUD / baud;
UART16550_WRITE(OFS_DIVISOR_LSB, divisor & 0xff);
UART16550_WRITE(OFS_DIVISOR_MSB, (divisor & 0xff00)>>8);
/* clear DIAB bit */
UART16550_WRITE(OFS_LINE_CONTROL, 0x0);
}
/* set data format */
UART16550_WRITE(OFS_DATA_FORMAT, data | parity | stop);
}
uint8 Uart16550GetPoll()
{
while((UART16550_READ(OFS_LINE_STATUS) & 0x1) == 0);
return UART16550_READ(OFS_RCV_BUFFER);
}
void Uart16550Put(uint8 byte)
{
while ((UART16550_READ(OFS_LINE_STATUS) &0x20) == 0);
UART16550_WRITE(OFS_SEND_BUFFER, byte);
}
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