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|
!
! This is a short helper to copy a zImage from high memory to low memory
! then call it.
!
org $1000
Start:
xor ax,ax
mov ds,ax
mov es,ax
mov ss,ax
mov sp,#Start
mov di,#8
nextpg:
mov cx,#$8000
mov ah,#$87
mov si,#GDT
int $15
jnc no_err
! If there's an error reset.
jmpi $0000,$FFFF
no_err:
inc srcaddr
inc destaddr
dec di
jnz nextpg
! Call the Image (same as bzImage)
go:
! Kill the floppy motor, needed in case the kernel has no floppy driver.
mov dx,#0x3f2
xor al, al
outb
! Setup required registers and go ...
mov ax,#$9000
mov bx,#$4000-12 ! Fix this to use boot_mem_top
mov es,ax
mov fs,ax
mov gs,ax
mov ds,ax
mov ss,ax
mov sp,bx
jmpi 0,$9020 ! Note SETUPSEG NOT INITSEG
! The global descriptor table.
GDT:
.word $0000,$0000
.word $0000,$0000
.word $0000,$0000
.word $0000,$0000
.word $FFFF,$0000
srcaddr:
.word $9310,$0000
.word $FFFF,$0000
destaddr:
.word $9301,$0000
.word $0000,$0000
.word $0000,$0000
.word $0000,$0000
.word $0000,$0000
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