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drop one more version of doing serial uart output differently.

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coreboot made it kind of complicated to print a character on serial. Not quite
as complicated as UEFI, but too much for a good design. Fix it.

Signed-off-by: Stefan Reinauer <stepan@coreboot.org>
Acked-by: Stefan Reinauer <stepan@coreboot.org>




git-svn-id: svn://svn.coreboot.org/coreboot/trunk@6191 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
This commit is contained in:
Stefan Reinauer
2010-12-17 00:08:21 +00:00
committed by Stefan Reinauer
parent efbfd501fe
commit 85b0fa1ace
17 changed files with 248 additions and 231 deletions
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98
src/lib/uart8250.c
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@@ -1,28 +1,36 @@
/* Should support 8250, 16450, 16550, 16550A type uarts */
/*
* This file is part of the coreboot project.
*
* Copyright (C) 2003 Eric Biederman
* Copyright (C) 2006-2010 coresystems GmbH
*
* 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; version 2 of the License.
*
* 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <arch/io.h>
#include <uart8250.h>
#include <pc80/mc146818rtc.h>
#if CONFIG_USE_OPTION_TABLE
#include "option_table.h"
#endif
/* Data */
#define UART_RBR 0x00
#define UART_TBR 0x00
/* Control */
#define UART_IER 0x01
#define UART_IIR 0x02
#define UART_FCR 0x02
#define UART_LCR 0x03
#define UART_MCR 0x04
#define UART_DLL 0x00
#define UART_DLM 0x01
/* Status */
#define UART_LSR 0x05
#define UART_MSR 0x06
#define UART_SCR 0x07
/* Should support 8250, 16450, 16550, 16550A type UARTs */
static inline int uart8250_can_tx_byte(unsigned base_port)
{
return inb(base_port + UART_LSR) & 0x20;
return inb(base_port + UART_LSR) & UART_MSR_DSR;
}
static inline void uart8250_wait_to_tx_byte(unsigned base_port)
@@ -33,7 +41,7 @@ static inline void uart8250_wait_to_tx_byte(unsigned base_port)
static inline void uart8250_wait_until_sent(unsigned base_port)
{
while(!(inb(base_port + UART_LSR) & 0x40))
while(!(inb(base_port + UART_LSR) & UART_LSR_TEMT))
;
}
@@ -47,7 +55,7 @@ void uart8250_tx_byte(unsigned base_port, unsigned char data)
int uart8250_can_rx_byte(unsigned base_port)
{
return inb(base_port + UART_LSR) & 0x01;
return inb(base_port + UART_LSR) & UART_LSR_DR;
}
unsigned char uart8250_rx_byte(unsigned base_port)
@@ -57,34 +65,56 @@ unsigned char uart8250_rx_byte(unsigned base_port)
return inb(base_port + UART_RBR);
}
void uart8250_init(unsigned base_port, unsigned divisor, unsigned lcs)
void uart8250_init(unsigned base_port, unsigned divisor)
{
lcs &= 0x7f;
/* disable interrupts */
/* Disable interrupts */
outb(0x0, base_port + UART_IER);
/* enable fifo's */
outb(0x01, base_port + UART_FCR);
/* Enable FIFOs */
outb(UART_FCR_FIFO_EN, base_port + UART_FCR);
/* assert DTR and RTS so the other end is happy */
outb(0x03, base_port + UART_MCR);
/* Set Baud Rate Divisor to 12 ==> 115200 Baud */
outb(0x80 | lcs, base_port + UART_LCR);
outb(UART_MCR_DTR | UART_MCR_RTS, base_port + UART_MCR);
/* DLAB on */
outb(UART_LCR_DLAB | CONFIG_TTYS0_LCS, base_port + UART_LCR);
/* Set Baud Rate Divisor. 12 ==> 115200 Baud */
outb(divisor & 0xFF, base_port + UART_DLL);
outb((divisor >> 8) & 0xFF, base_port + UART_DLM);
outb(lcs, base_port + UART_LCR);
/* Set to 3 for 8N1 */
outb(CONFIG_TTYS0_LCS, base_port + UART_LCR);
}
#ifndef __ROMCC__
/* Initialize a generic uart */
void init_uart8250(unsigned base_port, struct uart8250 *uart)
{
int divisor;
int lcs;
divisor = 115200/(uart->baud ? uart->baud: 1);
lcs = 3;
int divisor = uart->baud ? (115200/uart->baud) : 1;
if (base_port == CONFIG_TTYS0_BASE) {
/* Don't reinitialize the console serial port,
* This is espeically nasty in SMP.
* NOTE: The first invocation thus always needs to be
*/
return;
}
uart8250_init(base_port, divisor, lcs);
uart8250_init(base_port, divisor);
}
#endif
void uart_init(void)
{
#if CONFIG_USE_OPTION_TABLE
static const unsigned char divisor[] = { 1, 2, 3, 6, 12, 24, 48, 96 };
unsigned ttys0_div, ttys0_index;
ttys0_index = read_option(CMOS_VSTART_baud_rate, CMOS_VLEN_baud_rate, 0);
ttys0_index &= 7;
ttys0_div = divisor[ttys0_index];
uart8250_init(CONFIG_TTYS0_BASE, ttys0_div);
#else
uart8250_init(CONFIG_TTYS0_BASE, CONFIG_TTYS0_DIV);
#endif
}