1/*
2 * Copyright (c) 1998 Robert Nordier
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms are freely
6 * permitted provided that the above copyright notice and this
7 * paragraph and the following disclaimer are duplicated in all
8 * such forms.
9 *
10 * This software is provided "AS IS" and without any express or
11 * implied warranties, including, without limitation, the implied
12 * warranties of merchantability and fitness for a particular
13 * purpose.
14 *
| 1/*
2 * Copyright (c) 1998 Robert Nordier
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms are freely
6 * permitted provided that the above copyright notice and this
7 * paragraph and the following disclaimer are duplicated in all
8 * such forms.
9 *
10 * This software is provided "AS IS" and without any express or
11 * implied warranties, including, without limitation, the implied
12 * warranties of merchantability and fitness for a particular
13 * purpose.
14 *
|
15 * $FreeBSD: head/sys/boot/i386/boot2/sio.S 149212 2005-08-18 00:42:45Z iedowse $
| 15 * $FreeBSD: head/sys/boot/i386/boot2/sio.S 220337 2011-04-04 18:23:55Z rdivacky $
|
16 */
17
18 .set SIO_PRT,SIOPRT # Base port
19 .set SIO_FMT,SIOFMT # 8N1
20
21 .globl sio_init
22 .globl sio_flush
23 .globl sio_putc
24 .globl sio_getc
25 .globl sio_ischar
26
27/* void sio_init(int div) */
28
| 16 */
17
18 .set SIO_PRT,SIOPRT # Base port
19 .set SIO_FMT,SIOFMT # 8N1
20
21 .globl sio_init
22 .globl sio_flush
23 .globl sio_putc
24 .globl sio_getc
25 .globl sio_ischar
26
27/* void sio_init(int div) */
28
|
29sio_init: movw $SIO_PRT+0x3,%dx # Data format reg
| 29sio_init: pushl %eax
30 movw $SIO_PRT+0x3,%dx # Data format reg
|
30 movb $SIO_FMT|0x80,%al # Set format
31 outb %al,(%dx) # and DLAB
| 31 movb $SIO_FMT|0x80,%al # Set format
32 outb %al,(%dx) # and DLAB
|
32 pushl %edx # Save
| |
33 subb $0x3,%dl # Divisor latch reg
| 33 subb $0x3,%dl # Divisor latch reg
|
34 movl 0x8(%esp),%eax # Set
| 34 popl %eax
|
35 outw %ax,(%dx) # BPS
| 35 outw %ax,(%dx) # BPS
|
36 popl %edx # Restore
| 36 movw $SIO_PRT+0x3,%dx # Data format reg
|
37 movb $SIO_FMT,%al # Clear
38 outb %al,(%dx) # DLAB
39 incl %edx # Modem control reg
40 movb $0x3,%al # Set RTS,
41 outb %al,(%dx) # DTR
42 incl %edx # Line status reg
43 call sio_flush
| 37 movb $SIO_FMT,%al # Clear
38 outb %al,(%dx) # DLAB
39 incl %edx # Modem control reg
40 movb $0x3,%al # Set RTS,
41 outb %al,(%dx) # DTR
42 incl %edx # Line status reg
43 call sio_flush
|
44 ret $0x4
| 44 ret
|
45
46/* void sio_flush(void) */
47
48sio_flush.0: call sio_getc.1 # Get character
49sio_flush: call sio_ischar # Check for character
50 jnz sio_flush.0 # Till none
51 ret # To caller
52
53/* void sio_putc(int c) */
54
| 45
46/* void sio_flush(void) */
47
48sio_flush.0: call sio_getc.1 # Get character
49sio_flush: call sio_ischar # Check for character
50 jnz sio_flush.0 # Till none
51 ret # To caller
52
53/* void sio_putc(int c) */
54
|
55sio_putc: movw $SIO_PRT+0x5,%dx # Line status reg
| 55sio_putc: pushl %eax
56 movw $SIO_PRT+0x5,%dx # Line status reg
|
56 xor %ecx,%ecx # Timeout
57 movb $0x40,%ch # counter
58sio_putc.1: inb (%dx),%al # Transmitter
59 testb $0x20,%al # buffer empty?
60 loopz sio_putc.1 # No
61 jz sio_putc.2 # If timeout
| 57 xor %ecx,%ecx # Timeout
58 movb $0x40,%ch # counter
59sio_putc.1: inb (%dx),%al # Transmitter
60 testb $0x20,%al # buffer empty?
61 loopz sio_putc.1 # No
62 jz sio_putc.2 # If timeout
|
62 movb 0x4(%esp,1),%al # Get character
| 63 popl %eax # Get the character
|
63 subb $0x5,%dl # Transmitter hold reg
64 outb %al,(%dx) # Write character
| 64 subb $0x5,%dl # Transmitter hold reg
65 outb %al,(%dx) # Write character
|
65sio_putc.2: ret $0x4 # To caller
| 66sio_putc.2: ret # To caller
|
66
67/* int sio_getc(void) */
68
69sio_getc: call sio_ischar # Character available?
70 jz sio_getc # No
71sio_getc.1: subb $0x5,%dl # Receiver buffer reg
72 inb (%dx),%al # Read character
73 ret # To caller
74
75/* int sio_ischar(void) */
76
77sio_ischar: movw $SIO_PRT+0x5,%dx # Line status register
78 xorl %eax,%eax # Zero
79 inb (%dx),%al # Received data
80 andb $0x1,%al # ready?
81 ret # To caller
| 67
68/* int sio_getc(void) */
69
70sio_getc: call sio_ischar # Character available?
71 jz sio_getc # No
72sio_getc.1: subb $0x5,%dl # Receiver buffer reg
73 inb (%dx),%al # Read character
74 ret # To caller
75
76/* int sio_ischar(void) */
77
78sio_ischar: movw $SIO_PRT+0x5,%dx # Line status register
79 xorl %eax,%eax # Zero
80 inb (%dx),%al # Received data
81 andb $0x1,%al # ready?
82 ret # To caller
|