| 1 | /*
|
|---|
| 2 | * Copyright (C) 2005 Josef Cejka
|
|---|
| 3 | * All rights reserved.
|
|---|
| 4 | *
|
|---|
| 5 | * Redistribution and use in source and binary forms, with or without
|
|---|
| 6 | * modification, are permitted provided that the following conditions
|
|---|
| 7 | * are met:
|
|---|
| 8 | *
|
|---|
| 9 | * - Redistributions of source code must retain the above copyright
|
|---|
| 10 | * notice, this list of conditions and the following disclaimer.
|
|---|
| 11 | * - Redistributions in binary form must reproduce the above copyright
|
|---|
| 12 | * notice, this list of conditions and the following disclaimer in the
|
|---|
| 13 | * documentation and/or other materials provided with the distribution.
|
|---|
| 14 | * - The name of the author may not be used to endorse or promote products
|
|---|
| 15 | * derived from this software without specific prior written permission.
|
|---|
| 16 | *
|
|---|
| 17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
|---|
| 18 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
|---|
| 19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
|
|---|
| 20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|---|
| 21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
|
|---|
| 22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|---|
| 23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|---|
| 24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|---|
| 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
|
|---|
| 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|---|
| 27 | */
|
|---|
| 28 |
|
|---|
| 29 |
|
|---|
| 30 | #include <arch/boot/memmapasm.h>
|
|---|
| 31 |
|
|---|
| 32 | E820_RECORD_SIZE = MEMMAP_E820_RECORD_SIZE
|
|---|
| 33 | E820_MAX_RECORDS = MEMMAP_E820_MAX_RECORDS
|
|---|
| 34 | E820_SMAP = 0x534d4150
|
|---|
| 35 |
|
|---|
| 36 | .global memmap_arch_init
|
|---|
| 37 | .global e801memorysize
|
|---|
| 38 |
|
|---|
| 39 | .code16
|
|---|
| 40 | .section K_TEXT_START_2
|
|---|
| 41 |
|
|---|
| 42 | memmap_arch_init:
|
|---|
| 43 |
|
|---|
| 44 | e820begin:
|
|---|
| 45 | xorl %ebx,%ebx # during first call, ebx must be 0
|
|---|
| 46 | movw %bx,%ds
|
|---|
| 47 | movw %bx,%es
|
|---|
| 48 | movw $e820table_boot,%di
|
|---|
| 49 | movb $E820_MAX_RECORDS,e820counter_boot
|
|---|
| 50 | e820loop:
|
|---|
| 51 | movl $E820_SMAP,%edx # control sequence "SMAP"
|
|---|
| 52 |
|
|---|
| 53 | movl $0x0000e820,%eax # service
|
|---|
| 54 | movl $E820_RECORD_SIZE,%ecx
|
|---|
| 55 | int $0x15
|
|---|
| 56 | jc e820err
|
|---|
| 57 |
|
|---|
| 58 | cmpl $E820_SMAP,%eax # verifying BIOS
|
|---|
| 59 | jne e820err
|
|---|
| 60 |
|
|---|
| 61 | cmpl $E820_RECORD_SIZE,%ecx
|
|---|
| 62 | jne e820err # bad record size - bug in bios
|
|---|
| 63 |
|
|---|
| 64 | movw %di,%ax # next record
|
|---|
| 65 | addw $E820_RECORD_SIZE,%ax
|
|---|
| 66 | movw %ax,%di
|
|---|
| 67 |
|
|---|
| 68 | decb e820counter_boot # buffer is full
|
|---|
| 69 | jz e820end
|
|---|
| 70 |
|
|---|
| 71 | cmpl $0,%ebx
|
|---|
| 72 | jne e820loop
|
|---|
| 73 |
|
|---|
| 74 | e820end:
|
|---|
| 75 | movb $E820_MAX_RECORDS,%al
|
|---|
| 76 | subb e820counter_boot,%al
|
|---|
| 77 | movb %al,e820counter_boot # store # of valid entries in e820counter
|
|---|
| 78 |
|
|---|
| 79 | jmp e801begin
|
|---|
| 80 |
|
|---|
| 81 | e820err:
|
|---|
| 82 | movb $0,e820counter_boot
|
|---|
| 83 |
|
|---|
| 84 | # method e801 - get size of memory
|
|---|
| 85 |
|
|---|
| 86 | e801begin:
|
|---|
| 87 | xorw %dx,%dx
|
|---|
| 88 | xorw %cx,%cx
|
|---|
| 89 | xorw %bx,%bx
|
|---|
| 90 | movw $0xe801,%ax
|
|---|
| 91 | stc
|
|---|
| 92 | int $0x15
|
|---|
| 93 |
|
|---|
| 94 | jc e801end
|
|---|
| 95 |
|
|---|
| 96 | # fix problem with some BIOSes which use ax:bx rather than cx:dx
|
|---|
| 97 | testw %cx,%cx
|
|---|
| 98 | jnz e801cxdx
|
|---|
| 99 | testw %dx,%dx
|
|---|
| 100 | jnz e801cxdx
|
|---|
| 101 |
|
|---|
| 102 | movw %ax,%cx
|
|---|
| 103 | movw %bx,%dx
|
|---|
| 104 |
|
|---|
| 105 | e801cxdx:
|
|---|
| 106 | andl $0xffff,%edx
|
|---|
| 107 | shll $6,%edx
|
|---|
| 108 | andl $0xffff,%ecx
|
|---|
| 109 | addl %ecx,%edx
|
|---|
| 110 | addl $0x0400,%edx # add lower 1 MB - it's not included by e801 method
|
|---|
| 111 | movl %edx,e801memorysize
|
|---|
| 112 | e801end:
|
|---|
| 113 | ret
|
|---|
| 114 |
|
|---|
| 115 | #memory size in 1 kb chunks
|
|---|
| 116 | e801memorysize:
|
|---|
| 117 | .long 0
|
|---|
| 118 | |
|---|
