blob: f8ffbe604e021f444939bbe0ed0f617e176c951e [file] [log] [blame]
; -----------------------------------------------------------------------
; Copyright 1994-2008 H. Peter Anvin - All Rights Reserved
; This program is free software; you can redistribute it and/or modify
; it under the terms of the GNU General Public License as published by
; the Free Software Foundation, Inc., 53 Temple Place Ste 330,
; Bostom MA 02111-1307, USA; either version 2 of the License, or
; (at your option) any later version; incorporated herein by reference.
; -----------------------------------------------------------------------
; Memory layout of segments
; Memory below 0800h is reserved for the BIOS and the MBR.
BSS_START equ 0800h
; Text starts at the load address of 07C00h.
TEXT_START equ 7C00h
; The secondary BSS section, above the text; we really wish we could
; just make it follow .bcopy32 or hang off the end,
; but it doesn't seem to work that way.
; Reserve memory for the stack. This causes checkov to abort the
; compile if we violate this space.
STACK_SIZE equ 4096
%ifdef MAP
[map all MAP]
; The various sections and their relationship
; Use .earlybss for things that MUST be in low memory.
section .earlybss nobits start=BSS_START
section .bcopy32 align=4 valign=16 vfollows=.earlybss
section .config align=4 valign=16 follows=.bcopy32 vfollows=.bcopy32
section .config.end nobits valign=4 vfollows=.config
; Use .bss for things that doesn't have to be in low memory;
; with .bss1 and .bss2 to offload. .earlybss should be used
; for things that absolutely have to be below 0x7c00.
section .bss nobits valign=16 vfollows=.config.end
; Warning here: RBFG build 22 randomly overwrites
; memory location [0x5680,0x576c), possibly more. It
; seems that it gets confused and screws up the
; pointer to its own internal packet buffer and starts
; writing a received ARP packet into low memory.
section .rbfg nobits start=0x5680
RBFG_brainfuck: resb 2048 ; Bigger than an Ethernet packet...
; For section following .rbfg
section .bss2 nobits valign=16 vfollows=.rbfg
section .bss2 nobits valign=16 vfollows=.bss
section .text start=TEXT_START
; NASM BUG: .data always follows .text; can't override
section .data align=16 ; follows=.text
; This empty section works around a NASM bug with regards
; to follows= and nobits sections following a section which
; has VMA != LMA.
section .advpad progbits align=512 follows=.config
section .adv nobits align=512 follows=.advpad
; .uibss contains bss data which is guaranteed to be
; safe to clobber during the loading of the image. This
; is because while loading the primary image we will clobber
; the spillover from the last fractional sector load.
section .uibss nobits align=16 follows=.adv
; Normal bss...
section .bss1 nobits align=16 follows=.uibss
; Reserve space for stack
section .stack nobits align=16 start=STACK_START
Stack resb STACK_SIZE
StackTop equ $