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 *
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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 $
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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
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29sio_init: movw $SIO_PRT+0x3,%dx # Data format reg
| 29sio_init: pushl %eax 30 movw $SIO_PRT+0x3,%dx # Data format reg
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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
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32 pushl %edx # Save
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33 subb $0x3,%dl # Divisor latch reg
| 33 subb $0x3,%dl # Divisor latch reg
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34 movl 0x8(%esp),%eax # Set
| 34 popl %eax
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35 outw %ax,(%dx) # BPS
| 35 outw %ax,(%dx) # BPS
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36 popl %edx # Restore
| 36 movw $SIO_PRT+0x3,%dx # Data format reg
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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
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44 ret $0x4
| 44 ret
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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
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55sio_putc: movw $SIO_PRT+0x5,%dx # Line status reg
| 55sio_putc: pushl %eax 56 movw $SIO_PRT+0x5,%dx # Line status reg
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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
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62 movb 0x4(%esp,1),%al # Get character
| 63 popl %eax # Get the character
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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
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65sio_putc.2: ret $0x4 # To caller
| 66sio_putc.2: ret # To caller
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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
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