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Rev | Author | Line No. | Line |
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98 | cejka | 1 | /* |
2 | * Copyright (C) 2005 Josef Cejka |
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3 | * All rights reserved. |
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4 | * |
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5 | * Redistribution and use in source and binary forms, with or without |
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6 | * modification, are permitted provided that the following conditions |
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7 | * are met: |
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8 | * |
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9 | * - Redistributions of source code must retain the above copyright |
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10 | * notice, this list of conditions and the following disclaimer. |
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11 | * - Redistributions in binary form must reproduce the above copyright |
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12 | * notice, this list of conditions and the following disclaimer in the |
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13 | * documentation and/or other materials provided with the distribution. |
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14 | * - The name of the author may not be used to endorse or promote products |
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15 | * derived from this software without specific prior written permission. |
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16 | * |
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17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
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18 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
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19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
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20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
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21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
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22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
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23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
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24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
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25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
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26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
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27 | */ |
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95 | cejka | 28 | |
29 | |||
139 | cejka | 30 | #include <arch/boot/memmapasm.h> |
95 | cejka | 31 | |
98 | cejka | 32 | E820_SMAP = 0x534d4150 |
33 | |||
34 | .global memmap_arch_init |
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139 | cejka | 35 | .global e801memorysize |
98 | cejka | 36 | |
37 | .code16 |
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406 | jermar | 38 | .section K_TEXT_START_2, "ax" |
98 | cejka | 39 | |
95 | cejka | 40 | memmap_arch_init: |
98 | cejka | 41 | e820begin: |
347 | jermar | 42 | xorl %ebx,%ebx # during first call, ebx must be 0 |
243 | palkovsky | 43 | movw $e820table_boot,%di |
285 | decky | 44 | movb $MEMMAP_E820_MAX_RECORDS,e820counter_boot |
98 | cejka | 45 | e820loop: |
347 | jermar | 46 | movl $E820_SMAP,%edx # control sequence "SMAP" |
98 | cejka | 47 | |
347 | jermar | 48 | movl $0x0000e820,%eax # service |
285 | decky | 49 | movl $MEMMAP_E820_RECORD_SIZE,%ecx |
98 | cejka | 50 | int $0x15 |
139 | cejka | 51 | jc e820err |
98 | cejka | 52 | |
347 | jermar | 53 | cmpl $E820_SMAP,%eax # verifying BIOS |
139 | cejka | 54 | jne e820err |
55 | |||
285 | decky | 56 | cmpl $MEMMAP_E820_RECORD_SIZE,%ecx |
347 | jermar | 57 | jne e820err # bad record size - bug in bios |
98 | cejka | 58 | |
347 | jermar | 59 | movw %di,%ax # next record |
285 | decky | 60 | addw $MEMMAP_E820_RECORD_SIZE,%ax |
98 | cejka | 61 | movw %ax,%di |
62 | |||
347 | jermar | 63 | decb e820counter_boot # buffer is full |
101 | cejka | 64 | jz e820end |
98 | cejka | 65 | |
347 | jermar | 66 | testl %ebx,%ebx |
67 | jnz e820loop |
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101 | cejka | 68 | |
98 | cejka | 69 | e820end: |
285 | decky | 70 | movb $MEMMAP_E820_MAX_RECORDS,%al |
243 | palkovsky | 71 | subb e820counter_boot,%al |
347 | jermar | 72 | movb %al,e820counter_boot # store # of valid entries in e820counter |
139 | cejka | 73 | |
74 | jmp e801begin |
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75 | |||
76 | e820err: |
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243 | palkovsky | 77 | movb $0,e820counter_boot |
139 | cejka | 78 | |
79 | # method e801 - get size of memory |
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80 | |||
81 | e801begin: |
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82 | xorw %dx,%dx |
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83 | xorw %cx,%cx |
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84 | xorw %bx,%bx |
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85 | movw $0xe801,%ax |
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86 | stc |
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87 | int $0x15 |
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98 | cejka | 88 | |
139 | cejka | 89 | jc e801end |
90 | |||
347 | jermar | 91 | # fix problem with some BIOSes which use ax:bx rather than cx:dx |
139 | cejka | 92 | testw %cx,%cx |
93 | jnz e801cxdx |
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94 | testw %dx,%dx |
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95 | jnz e801cxdx |
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96 | |||
97 | movw %ax,%cx |
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98 | movw %bx,%dx |
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99 | |||
100 | e801cxdx: |
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101 | andl $0xffff,%edx |
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102 | shll $6,%edx |
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103 | andl $0xffff,%ecx |
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104 | addl %ecx,%edx |
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347 | jermar | 105 | addl $0x0400,%edx # add lower 1 MB - it's not included by e801 method |
149 | jermar | 106 | movl %edx,e801memorysize |
139 | cejka | 107 | e801end: |
98 | cejka | 108 | ret |
109 | |||
347 | jermar | 110 | |
406 | jermar | 111 | .section K_DATA_START, "aw", @progbits |
347 | jermar | 112 | |
113 | #memory size in 1 kb chunks |
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139 | cejka | 114 | e801memorysize: |
115 | .long 0 |