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 128716 2004-04-28 14:31:44Z ru $
| 15 * $FreeBSD: head/sys/boot/i386/boot2/sio.S 129240 2004-05-14 20:29:30Z ru $
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16 */ 17
| 16 */ 17
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18 .set SIO_PRT,SIOPRT // Base port 19 .set SIO_FMT,SIOFMT // 8N1 20 .set SIO_DIV,(115200/SIOSPD) // 115200 / SPD
| 18 .set SIO_PRT,SIOPRT # Base port 19 .set SIO_FMT,SIOFMT # 8N1 20 .set SIO_DIV,(115200/SIOSPD) # 115200 / SPD
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21 22 .globl sio_init 23 .globl sio_flush 24 .globl sio_putc 25 .globl sio_getc 26 .globl sio_ischar 27 28/* void sio_init(void) */ 29
| 21 22 .globl sio_init 23 .globl sio_flush 24 .globl sio_putc 25 .globl sio_getc 26 .globl sio_ischar 27 28/* void sio_init(void) */ 29
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30sio_init: movw $SIO_PRT+0x3,%dx // Data format reg 31 movb $SIO_FMT|0x80,%al // Set format 32 outb %al,(%dx) // and DLAB 33 pushl %edx // Save 34 subb $0x3,%dl // Divisor latch reg 35 movw $SIO_DIV,%ax // Set 36 outw %ax,(%dx) // BPS 37 popl %edx // Restore 38 movb $SIO_FMT,%al // Clear 39 outb %al,(%dx) // DLAB 40 incl %edx // Modem control reg 41 movb $0x3,%al // Set RTS, 42 outb %al,(%dx) // DTR 43 incl %edx // Line status reg
| 30sio_init: movw $SIO_PRT+0x3,%dx # Data format reg 31 movb $SIO_FMT|0x80,%al # Set format 32 outb %al,(%dx) # and DLAB 33 pushl %edx # Save 34 subb $0x3,%dl # Divisor latch reg 35 movw $SIO_DIV,%ax # Set 36 outw %ax,(%dx) # BPS 37 popl %edx # Restore 38 movb $SIO_FMT,%al # Clear 39 outb %al,(%dx) # DLAB 40 incl %edx # Modem control reg 41 movb $0x3,%al # Set RTS, 42 outb %al,(%dx) # DTR 43 incl %edx # Line status reg
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44 45/* void sio_flush(void) */ 46
| 44 45/* void sio_flush(void) */ 46
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47sio_flush.0: call sio_getc.1 // Get character 48sio_flush: call sio_ischar // Check for character 49 jnz sio_flush.0 // Till none 50 ret // To caller
| 47sio_flush.0: call sio_getc.1 # Get character 48sio_flush: call sio_ischar # Check for character 49 jnz sio_flush.0 # Till none 50 ret # To caller
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51 52/* void sio_putc(int c) */ 53
| 51 52/* void sio_putc(int c) */ 53
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54sio_putc: movw $SIO_PRT+0x5,%dx // Line status reg 55 xor %ecx,%ecx // Timeout 56 movb $0x40,%ch // counter 57sio_putc.1: inb (%dx),%al // Transmitter 58 testb $0x20,%al // buffer empty? 59 loopz sio_putc.1 // No 60 jz sio_putc.2 // If timeout 61 movb 0x4(%esp,1),%al // Get character 62 subb $0x5,%dl // Transmitter hold reg 63 outb %al,(%dx) // Write character 64sio_putc.2: ret $0x4 // To caller
| 54sio_putc: movw $SIO_PRT+0x5,%dx # Line status reg 55 xor %ecx,%ecx # Timeout 56 movb $0x40,%ch # counter 57sio_putc.1: inb (%dx),%al # Transmitter 58 testb $0x20,%al # buffer empty? 59 loopz sio_putc.1 # No 60 jz sio_putc.2 # If timeout 61 movb 0x4(%esp,1),%al # Get character 62 subb $0x5,%dl # Transmitter hold reg 63 outb %al,(%dx) # Write character 64sio_putc.2: ret $0x4 # To caller
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65 66/* int sio_getc(void) */ 67
| 65 66/* int sio_getc(void) */ 67
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68sio_getc: call sio_ischar // Character available? 69 jz sio_getc // No 70sio_getc.1: subb $0x5,%dl // Receiver buffer reg 71 inb (%dx),%al // Read character 72 ret // To caller
| 68sio_getc: call sio_ischar # Character available? 69 jz sio_getc # No 70sio_getc.1: subb $0x5,%dl # Receiver buffer reg 71 inb (%dx),%al # Read character 72 ret # To caller
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73 74/* int sio_ischar(void) */ 75
| 73 74/* int sio_ischar(void) */ 75
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76sio_ischar: movw $SIO_PRT+0x5,%dx // Line status register 77 xorl %eax,%eax // Zero 78 inb (%dx),%al // Received data 79 andb $0x1,%al // ready? 80 ret // To caller
| 76sio_ischar: movw $SIO_PRT+0x5,%dx # Line status register 77 xorl %eax,%eax # Zero 78 inb (%dx),%al # Received data 79 andb $0x1,%al # ready? 80 ret # To caller
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