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pyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Marius Groeger <mgroeger@sysgo.de>
*
* (C) Copyright 2002
* ght 2002-2004
* Wolfgang Denk, DENX Software Engineering, <wd@denx.de>
*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Marius Groeger <mgroeger@sysgo.de>
*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Alex Zuepke <azu@sysgo.de>
*
* Copyright (C) 1999 2000 2001 Erik Mouw (J.A.K.Mouw@its.tudelft.nl)
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/hardware.h>
DECLARE_GLOBAL_DATA_PTR;
/* flush serial input queue. returns 0 on success or negative error
* number otherwise
*/
static int serial_flush_input(void)
{
volatile u32 tmp;
/* keep on reading as long as the receiver is not empty */
while(UTRSTAT0&0x01) {
tmp = REGB(URXH0);
}
return 0;
}
/* flush output queue. returns 0 on success or negative error number
* otherwise
*/
static int serial_flush_output(void)
{
/* wait until the transmitter is no longer busy */
while(!(UTRSTAT0 & 0x02)) {
}
return 0;
}
static void s3c44b0_serial_setbrg(void)
{
u32 divisor = 0;
/* get correct divisor */
switch(gd->baudrate) {
case 1200:
#if CONFIG_S3C44B0_CLOCK_SPEED==66
divisor = 3124;
#elif CONFIG_S3C44B0_CLOCK_SPEED==75
divisor = 3905;
#else
# error CONFIG_S3C44B0_CLOCK_SPEED undefined
#endif
break;
case 9600:
#if CONFIG_S3C44B0_CLOCK_SPEED==66
divisor = 390;
#elif CONFIG_S3C44B0_CLOCK_SPEED==75
divisor = 487;
#else
# error CONFIG_S3C44B0_CLOCK_SPEED undefined
#endif
break;
case 19200:
#if CONFIG_S3C44B0_CLOCK_SPEED==66
divisor = 194;
#elif CONFIG_S3C44B0_CLOCK_SPEED==75
divisor = 243;
#else
# error CONFIG_S3C44B0_CLOCK_SPEED undefined
#endif
break;
case 38400:
#if CONFIG_S3C44B0_CLOCK_SPEED==66
divisor = 97;
#elif CONFIG_S3C44B0_CLOCK_SPEED==75
divisor = 121;
#else
# error CONFIG_S3C44B0_CLOCK_SPEED undefined
#endif /* break; */
case 57600:
#if CONFIG_S3C44B0_CLOCK_SPEED==66
divisor = 64;
#elif CONFIG_S3C44B0_CLOCK_SPEED==75
divisor = 80;
#else
# error CONFIG_S3C44B0_CLOCK_SPEED undefined
#endif /* break; */
case 115200:
#if CONFIG_S3C44B0_CLOCK_SPEED==66
divisor = 32;
#elif CONFIG_S3C44B0_CLOCK_SPEED==75
divisor = 40;
#else
# error CONFIG_S3C44B0_CLOCK_SPEED undefined
#endif /* break; */
}
serial_flush_output();
serial_flush_input();
UFCON0 = 0x0;
ULCON0 = 0x03;
UCON0 = 0x05;
UBRDIV0 = divisor;
UFCON1 = 0x0;
ULCON1 = 0x03;
UCON1 = 0x05;
UBRDIV1 = divisor;
for(divisor=0; divisor<100; divisor++) {
/* NOP */
}
}
/*
* Initialise the serial port with the given baudrate. The settings
* are always 8 data bits, no parity, 1 stop bit, no start bits.
*
*/
static int s3c44b0_serial_init(void)
{
serial_setbrg ();
return (0);
}
/*
* Output a single byte to the serial port.
*/
static void s3c44b0_serial_putc(const char c)
{
/* wait for room in the transmit FIFO */
while(!(UTRSTAT0 & 0x02));
UTXH0 = (unsigned char)c;
/*
to be polite with serial console add a line feed
to the carriage return character
*/
if (c=='\n')
serial_putc('\r');
}
/*
* Read a single byte from the serial port. Returns 1 on success, 0
* otherwise. When the function is succesfull, the character read is
* written into its argument c.
*/
static int s3c44b0_serial_tstc(void)
{
return (UTRSTAT0 & 0x01);
}
/*
* Read a single byte from the serial port. Returns 1 on success, 0
* otherwise. When the function is succesfull, the character read is
* written into its argument c.
*/
static int s3c44b0_serial_getc(void)
{
int rv;
for(;;) {
rv = s3c44b0_serial_tstc();
if(rv > 0)
return URXH0;
}
}
static struct serial_device s3c44b0_serial_drv = {
.name = "s3c44b0_serial",
.start = s3c44b0_serial_init,
.stop = NULL,
.setbrg = s3c44b0_serial_setbrg,
.putc = s3c44b0_serial_putc,
.puts = default_serial_puts,
.getc = s3c44b0_serial_getc,
.tstc = s3c44b0_serial_tstc,
};
void s3c44b0_serial_initialize(void)
{
serial_register(&s3c44b0_serial_drv);
}
__weak struct serial_device *default_serial_console(void)
{
return &s3c44b0_serial_drv;
}
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