u-boot/drivers/serial/serial_pl01x.c
Matt Waddel 249d5219c4 ARMV7: Fixed baudrate setting in pl01x driver
The pl01x serial driver was lacking the code to switch baudrates from the
command line.  Fixed by simply saving the new baudrate and calling
serial_init() again.  Also fixed CamelCase variables, I/O accessors and
comment style.

Signed-off-by: Matt Waddel <matt.waddel@linaro.org>
2010-10-13 09:59:43 +02:00

206 lines
4.7 KiB
C

/*
* (C) Copyright 2000
* Rob Taylor, Flying Pig Systems. robt@flyingpig.com.
*
* (C) Copyright 2004
* ARM Ltd.
* Philippe Robin, <philippe.robin@arm.com>
*
* 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
*/
/* Simple U-Boot driver for the PrimeCell PL010/PL011 UARTs */
#include <common.h>
#include <watchdog.h>
#include <asm/io.h>
#include "serial_pl01x.h"
/*
* Integrator AP has two UARTs, we use the first one, at 38400-8-N-1
* Integrator CP has two UARTs, use the first one, at 38400-8-N-1
* Versatile PB has four UARTs.
*/
#define CONSOLE_PORT CONFIG_CONS_INDEX
static volatile unsigned char *const port[] = CONFIG_PL01x_PORTS;
#define NUM_PORTS (sizeof(port)/sizeof(port[0]))
static void pl01x_putc (int portnum, char c);
static int pl01x_getc (int portnum);
static int pl01x_tstc (int portnum);
unsigned int baudrate = CONFIG_BAUDRATE;
DECLARE_GLOBAL_DATA_PTR;
#ifdef CONFIG_PL010_SERIAL
int serial_init (void)
{
unsigned int divisor;
/* First, disable everything */
writel(0x0, port[CONSOLE_PORT] + UART_PL010_CR);
/* Set baud rate */
switch (baudrate) {
case 9600:
divisor = UART_PL010_BAUD_9600;
break;
case 19200:
divisor = UART_PL010_BAUD_9600;
break;
case 38400:
divisor = UART_PL010_BAUD_38400;
break;
case 57600:
divisor = UART_PL010_BAUD_57600;
break;
case 115200:
divisor = UART_PL010_BAUD_115200;
break;
default:
divisor = UART_PL010_BAUD_38400;
}
writel(((divisor & 0xf00) >> 8), port[CONSOLE_PORT] + UART_PL010_LCRM);
writel((divisor & 0xff), port[CONSOLE_PORT] + UART_PL010_LCRL);
/* Set the UART to be 8 bits, 1 stop bit, no parity, fifo enabled */
writel((UART_PL010_LCRH_WLEN_8 | UART_PL010_LCRH_FEN),
port[CONSOLE_PORT] + UART_PL010_LCRH);
/* Finally, enable the UART */
writel((UART_PL010_CR_UARTEN), port[CONSOLE_PORT] + UART_PL010_CR);
return 0;
}
#endif /* CONFIG_PL010_SERIAL */
#ifdef CONFIG_PL011_SERIAL
int serial_init (void)
{
unsigned int temp;
unsigned int divider;
unsigned int remainder;
unsigned int fraction;
/* First, disable everything */
writel(0x0, port[CONSOLE_PORT] + UART_PL011_CR);
/*
* Set baud rate
*
* IBRD = UART_CLK / (16 * BAUD_RATE)
* FBRD = RND((64 * MOD(UART_CLK,(16 * BAUD_RATE))) / (16 * BAUD_RATE))
*/
temp = 16 * baudrate;
divider = CONFIG_PL011_CLOCK / temp;
remainder = CONFIG_PL011_CLOCK % temp;
temp = (8 * remainder) / baudrate;
fraction = (temp >> 1) + (temp & 1);
writel(divider, port[CONSOLE_PORT] + UART_PL011_IBRD);
writel(fraction, port[CONSOLE_PORT] + UART_PL011_FBRD);
/* Set the UART to be 8 bits, 1 stop bit, no parity, fifo enabled */
writel((UART_PL011_LCRH_WLEN_8 | UART_PL011_LCRH_FEN),
port[CONSOLE_PORT] + UART_PL011_LCRH);
/* Finally, enable the UART */
writel((UART_PL011_CR_UARTEN | UART_PL011_CR_TXE | UART_PL011_CR_RXE),
port[CONSOLE_PORT] + UART_PL011_CR);
return 0;
}
#endif /* CONFIG_PL011_SERIAL */
void serial_putc (const char c)
{
if (c == '\n')
pl01x_putc (CONSOLE_PORT, '\r');
pl01x_putc (CONSOLE_PORT, c);
}
void serial_puts (const char *s)
{
while (*s) {
serial_putc (*s++);
}
}
int serial_getc (void)
{
return pl01x_getc (CONSOLE_PORT);
}
int serial_tstc (void)
{
return pl01x_tstc (CONSOLE_PORT);
}
void serial_setbrg (void)
{
baudrate = gd->baudrate;
serial_init();
}
static void pl01x_putc (int portnum, char c)
{
/* Wait until there is space in the FIFO */
while (readl(port[portnum] + UART_PL01x_FR) & UART_PL01x_FR_TXFF)
WATCHDOG_RESET();
/* Send the character */
writel(c, port[portnum] + UART_PL01x_DR);
}
static int pl01x_getc (int portnum)
{
unsigned int data;
/* Wait until there is data in the FIFO */
while (readl(port[portnum] + UART_PL01x_FR) & UART_PL01x_FR_RXFE)
WATCHDOG_RESET();
data = readl(port[portnum] + UART_PL01x_DR);
/* Check for an error flag */
if (data & 0xFFFFFF00) {
/* Clear the error */
writel(0xFFFFFFFF, port[portnum] + UART_PL01x_ECR);
return -1;
}
return (int) data;
}
static int pl01x_tstc (int portnum)
{
WATCHDOG_RESET();
return !(readl(port[portnum] + UART_PL01x_FR) &
UART_PL01x_FR_RXFE);
}