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/*
* Jz47xx UART support
*
* Hardcoded to UART 0 for now
* Options also hardcoded to 8N1
*
* Copyright (c) 2005
* Ingenic Semiconductor, <jlwei@ingenic.cn>
*
* 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 <config.h>
#if defined(CONFIG_JZ4740)
#include <common.h>
#include <asm/jz4740.h>
#undef UART_BASE
#ifndef CONFIG_SYS_UART_BASE
#define UART_BASE UART0_BASE
#else
#define UART_BASE CONFIG_SYS_UART_BASE
#endif
/******************************************************************************
*
* serial_init - initialize a channel
*
* This routine initializes the number of data bits, parity
* and set the selected baud rate. Interrupts are disabled.
* Set the modem control signals if the option is selected.
*
* RETURNS: N/A
*/
int serial_init (void)
{
#if !defined(CONFIG_NAND_U_BOOT) || defined(CONFIG_NAND_SPL)
volatile u8 *uart_fcr = (volatile u8 *)(UART_BASE + OFF_FCR);
volatile u8 *uart_lcr = (volatile u8 *)(UART_BASE + OFF_LCR);
volatile u8 *uart_ier = (volatile u8 *)(UART_BASE + OFF_IER);
volatile u8 *uart_sircr = (volatile u8 *)(UART_BASE + OFF_SIRCR);
/* Disable port interrupts while changing hardware */
*uart_ier = 0;
/* Disable UART unit function */
*uart_fcr = ~UART_FCR_UUE;
/* Set both receiver and transmitter in UART mode (not SIR) */
*uart_sircr = ~(SIRCR_RSIRE | SIRCR_TSIRE);
/* Set databits, stopbits and parity. (8-bit data, 1 stopbit, no parity) */
*uart_lcr = UART_LCR_WLEN_8 | UART_LCR_STOP_1;
/* Set baud rate */
serial_setbrg();
/* Enable UART unit, enable and clear FIFO */
*uart_fcr = UART_FCR_UUE | UART_FCR_FE | UART_FCR_TFLS | UART_FCR_RFLS;
#endif
return 0;
}
void serial_setbrg (void)
{
volatile u8 *uart_lcr = (volatile u8 *)(UART_BASE + OFF_LCR);
volatile u8 *uart_dlhr = (volatile u8 *)(UART_BASE + OFF_DLHR);
volatile u8 *uart_dllr = (volatile u8 *)(UART_BASE + OFF_DLLR);
u32 baud_div, tmp;
baud_div = CONFIG_SYS_EXTAL / 16 / CONFIG_BAUDRATE;
tmp = *uart_lcr;
tmp |= UART_LCR_DLAB;
*uart_lcr = tmp;
*uart_dlhr = (baud_div >> 8) & 0xff;
*uart_dllr = baud_div & 0xff;
tmp &= ~UART_LCR_DLAB;
*uart_lcr = tmp;
}
void serial_putc (const char c)
{
volatile u8 *uart_lsr = (volatile u8 *)(UART_BASE + OFF_LSR);
volatile u8 *uart_tdr = (volatile u8 *)(UART_BASE + OFF_TDR);
if (c == '\n') serial_putc ('\r');
/* Wait for fifo to shift out some bytes */
while ( !((*uart_lsr & (UART_LSR_TDRQ | UART_LSR_TEMT)) == 0x60) );
*uart_tdr = (u8)c;
}
void serial_puts (const char *s)
{
while (*s) {
serial_putc (*s++);
}
}
int serial_getc (void)
{
volatile u8 *uart_rdr = (volatile u8 *)(UART_BASE + OFF_RDR);
while (!serial_tstc());
return *uart_rdr;
}
int serial_tstc (void)
{
volatile u8 *uart_lsr = (volatile u8 *)(UART_BASE + OFF_LSR);
if (*uart_lsr & UART_LSR_DR) {
/* Data in rfifo */
return (1);
}
return 0;
}
#endif