u-boot/cpu/bf533/serial.c

195 lines
4.2 KiB
C

/*
* U-boot - serial.c Serial driver for BF533
*
* Copyright (c) 2005 blackfin.uclinux.org
*
* This file is based on
* bf533_serial.c: Serial driver for BlackFin BF533 DSP internal UART.
* Copyright (c) 2003 Bas Vermeulen <bas@buyways.nl>,
* BuyWays B.V. (www.buyways.nl)
*
* Based heavily on blkfinserial.c
* blkfinserial.c: Serial driver for BlackFin DSP internal USRTs.
* Copyright(c) 2003 Metrowerks <mwaddel@metrowerks.com>
* Copyright(c) 2001 Tony Z. Kou <tonyko@arcturusnetworks.com>
* Copyright(c) 2001-2002 Arcturus Networks Inc. <www.arcturusnetworks.com>
*
* Based on code from 68328 version serial driver imlpementation which was:
* Copyright (C) 1995 David S. Miller <davem@caip.rutgers.edu>
* Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com>
* Copyright (C) 1998, 1999 D. Jeff Dionne <jeff@uclinux.org>
* Copyright (C) 1999 Vladimir Gurevich <vgurevic@cisco.com>
*
* (C) Copyright 2000-2004
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* See file CREDITS for list of people who contributed to this
* project.
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <asm/irq.h>
#include <asm/system.h>
#include <asm/segment.h>
#include <asm/bitops.h>
#include <asm/delay.h>
#include <asm/uaccess.h>
#include "bf533_serial.h"
DECLARE_GLOBAL_DATA_PTR;
unsigned long pll_div_fact;
void calc_baud(void)
{
unsigned char i;
int temp;
for(i = 0; i < sizeof(baud_table)/sizeof(int); i++) {
temp = CONFIG_SCLK_HZ/(baud_table[i]*8);
if ( temp && 0x1 == 1 ) {
temp++;
}
temp = temp/2;
hw_baud_table[i].dl_high = (temp >> 8)& 0xFF;
hw_baud_table[i].dl_low = (temp) & 0xFF;
}
}
void serial_setbrg(void)
{
int i;
calc_baud();
for (i = 0; i < sizeof(baud_table) / sizeof(int); i++) {
if (gd->baudrate == baud_table[i])
break;
}
/* Enable UART */
*pUART_GCTL |= UART_GCTL_UCEN;
asm("ssync;");
/* Set DLAB in LCR to Access DLL and DLH */
ACCESS_LATCH;
asm("ssync;");
*pUART_DLL = hw_baud_table[i].dl_low;
asm("ssync;");
*pUART_DLH = hw_baud_table[i].dl_high;
asm("ssync;");
/* Clear DLAB in LCR to Access THR RBR IER */
ACCESS_PORT_IER;
asm("ssync;");
/* Enable ERBFI and ELSI interrupts
* to poll SIC_ISR register*/
*pUART_IER = UART_IER_ELSI | UART_IER_ERBFI | UART_IER_ETBEI;
asm("ssync;");
/* Set LCR to Word Lengh 8-bit word select */
*pUART_LCR = UART_LCR_WLS8;
asm("ssync;");
return;
}
int serial_init(void)
{
serial_setbrg();
return (0);
}
void serial_putc(const char c)
{
if ((*pUART_LSR) & UART_LSR_TEMT)
{
if (c == '\n')
serial_putc('\r');
local_put_char(c);
}
while (!((*pUART_LSR) & UART_LSR_TEMT))
SYNC_ALL;
return;
}
int serial_tstc(void)
{
if (*pUART_LSR & UART_LSR_DR)
return 1;
else
return 0;
}
int serial_getc(void)
{
unsigned short uart_lsr_val, uart_rbr_val;
unsigned long isr_val;
int ret;
/* Poll for RX Interrupt */
while (!((isr_val = *(volatile unsigned long *)SIC_ISR) & IRQ_UART_RX_BIT));
asm("csync;");
uart_lsr_val = *pUART_LSR; /* Clear status bit */
uart_rbr_val = *pUART_RBR; /* getc() */
if (isr_val & IRQ_UART_ERROR_BIT) {
ret = -1;
}
else
{
ret = uart_rbr_val & 0xff;
}
return ret;
}
void serial_puts(const char *s)
{
while (*s) {
serial_putc(*s++);
}
}
static void local_put_char(char ch)
{
int flags = 0;
unsigned long isr_val;
save_and_cli(flags);
/* Poll for TX Interruput */
while (!((isr_val = *pSIC_ISR) & IRQ_UART_TX_BIT));
asm("csync;");
*pUART_THR = ch; /* putc() */
if (isr_val & IRQ_UART_ERROR_BIT) {
printf("?");
}
restore_flags(flags);
return ;
}