f778c9da00
Obtained from: bios boot block changed to allow booting from both the attached graphics display and from a serial port. (A specially compiled serial boot block is no longer necessary.) The boot block should detect the presence or absence of a keyboard: if there is no keyboard, COM1 is turned into the console. This simulates the behavior of the Sun boot PROMs. Unplug your keyboard, attach a terminal to COM1 and you should be ready to go. :)
199 lines
5.2 KiB
ArmAsm
199 lines
5.2 KiB
ArmAsm
/*
|
|
* Mach Operating System
|
|
* Copyright (c) 1992, 1991 Carnegie Mellon University
|
|
* All Rights Reserved.
|
|
*
|
|
* Permission to use, copy, modify and distribute this software and its
|
|
* documentation is hereby granted, provided that both the copyright
|
|
* notice and this permission notice appear in all copies of the
|
|
* software, derivative works or modified versions, and any portions
|
|
* thereof, and that both notices appear in supporting documentation.
|
|
*
|
|
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
|
|
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
|
|
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
|
|
*
|
|
* Carnegie Mellon requests users of this software to return to
|
|
*
|
|
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
|
|
* School of Computer Science
|
|
* Carnegie Mellon University
|
|
* Pittsburgh PA 15213-3890
|
|
*
|
|
* any improvements or extensions that they make and grant Carnegie Mellon
|
|
* the rights to redistribute these changes.
|
|
*
|
|
* from: Mach, Revision 2.2 92/04/04 11:34:26 rpd
|
|
* $Id: bios.S,v 1.1 1994/12/18 20:12:08 joerg Exp $
|
|
*/
|
|
|
|
/*
|
|
Copyright 1988, 1989, 1990, 1991, 1992
|
|
by Intel Corporation, Santa Clara, California.
|
|
|
|
All Rights Reserved
|
|
|
|
Permission to use, copy, modify, and distribute this software and
|
|
its documentation for any purpose and without fee is hereby
|
|
granted, provided that the above copyright notice appears in all
|
|
copies and that both the copyright notice and this permission notice
|
|
appear in supporting documentation, and that the name of Intel
|
|
not be used in advertising or publicity pertaining to distribution
|
|
of the software without specific, written prior permission.
|
|
|
|
INTEL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
|
|
INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS,
|
|
IN NO EVENT SHALL INTEL BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
|
|
CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
|
|
LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
|
|
NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
|
|
WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
|
*/
|
|
|
|
/*
|
|
* Serial bootblock interface routines
|
|
* Copyright (c) 1994, J"org Wunsch
|
|
*
|
|
* Permission to use, copy, modify and distribute this software and its
|
|
* documentation is hereby granted, provided that both the copyright
|
|
* notice and this permission notice appear in all copies of the
|
|
* software, derivative works or modified versions, and any portions
|
|
* thereof, and that both notices appear in supporting documentation.
|
|
*
|
|
* THE AUTHOR ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
|
|
* CONDITION. THE AUTHOR DISCLAIMS ANY LIABILITY OF ANY KIND FOR
|
|
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
|
|
*/
|
|
|
|
.file "serial.s"
|
|
|
|
#include "asm.h"
|
|
.text
|
|
|
|
/*
|
|
* The serial port interface routines implement a simple polled i/o
|
|
* interface to a standard serial port. Due to the space restrictions
|
|
* for the boot blocks, no BIOS support is used (since BIOS requires
|
|
* expensive real/protected mode switches), instead the rudimentary
|
|
* BIOS support is duplicated here.
|
|
*
|
|
* The base address for the i/o port is passed from the Makefile in
|
|
* the COMCONSOLE preprocessor macro. Console parameters are currently
|
|
* hard-coded to 9600 Bd, 8 bit. This can be changed in the
|
|
* init_serial() function.
|
|
*/
|
|
|
|
/*
|
|
* void serial_putc(char ch)
|
|
* send ch to serial port
|
|
*
|
|
*/
|
|
|
|
ENTRY(serial_putc)
|
|
push %ebp
|
|
mov %esp, %ebp
|
|
push %edx
|
|
|
|
mov $COMCONSOLE + 5, %edx # line status reg
|
|
1: inb %dx, %al
|
|
test $0x20, %al
|
|
jz 1b # TX buffer not empty
|
|
|
|
movb 0x8(%ebp), %al
|
|
|
|
sub $5, %edx # TX output reg
|
|
outb %al, %dx # send this one
|
|
|
|
pop %edx
|
|
pop %ebp
|
|
ret
|
|
|
|
/*
|
|
* int serial_getc(void)
|
|
* read a character from serial port
|
|
*/
|
|
|
|
ENTRY(serial_getc)
|
|
push %ebp
|
|
mov %esp, %ebp
|
|
push %edx
|
|
|
|
mov $COMCONSOLE + 5, %edx # line status reg
|
|
1:
|
|
inb %dx, %al
|
|
testb $0x01, %al
|
|
jz 1b # no RX char available
|
|
|
|
xor %eax, %eax
|
|
sub $5, %edx # RX buffer reg
|
|
inb %dx, %al # fetch (first) character
|
|
|
|
cmp $0x7F, %eax # make DEL...
|
|
jne 2f
|
|
mov $0x08, %eax # look like BS
|
|
2:
|
|
pop %edx
|
|
pop %ebp
|
|
ret
|
|
|
|
/*
|
|
* int serial_ischar(void)
|
|
* if there is a character pending, return true; otherwise return 0
|
|
*/
|
|
ENTRY(serial_ischar)
|
|
push %ebp
|
|
mov %esp, %ebp
|
|
push %edx
|
|
|
|
xorl %eax, %eax
|
|
mov $COMCONSOLE + 5, %edx # line status reg
|
|
inb %dx, %al
|
|
andb $0x01, %al # RX char available?
|
|
|
|
pop %edx
|
|
pop %ebp
|
|
ret
|
|
|
|
/*
|
|
* void init_serial(void)
|
|
* initialize the serial console port to 9600 Bd, 8 bpc
|
|
*/
|
|
ENTRY(init_serial)
|
|
push %ebp
|
|
mov %esp, %ebp
|
|
push %edx
|
|
|
|
mov $COMCONSOLE + 3, %edx # line control reg
|
|
movb $0x80, %al
|
|
outb %al, %dx # enable DLAB
|
|
|
|
sub $3, %edx # divisor latch, low byte
|
|
mov $12, %ax # divisor 12: 9600 Bd
|
|
outb %al, %dx
|
|
inc %edx # divisor latch, high byte
|
|
movb %ah, %al
|
|
outb %al, %dx
|
|
|
|
add $2, %edx # line control reg
|
|
movb $0x13, %al
|
|
outb %al, %dx # 8 bit, no parity, 1 stop bit
|
|
|
|
inc %edx # modem control reg
|
|
mov $3, %al
|
|
outb %al, %dx # enable DTR/RTS
|
|
|
|
/* now finally, flush the input buffer */
|
|
inc %edx # line status reg
|
|
1:
|
|
inb %dx, %al
|
|
testb $0x01, %al
|
|
jz 2f # no more characters buffered
|
|
sub $5, %edx # rx buffer reg
|
|
inb %dx, %al # throw away
|
|
add $5, %edx
|
|
jmp 1b
|
|
2:
|
|
pop %edx
|
|
pop %ebp
|
|
ret
|