; ----------------------------------------------------------------------- ; ; 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. ; ; ----------------------------------------------------------------------- ; ; layout.inc ; ; Memory layout of segments ; ; Default to 16-bit code bits 16 ; 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. LATEBSS_START equ 0B800h %ifdef MAP [map all MAP] %endif ; ; The various sections and their relationship ; ; Use .earlybss for things that MUST be in low memory. section .earlybss nobits start=BSS_START section .bcopy32 exec nowrite progbits align=4 section .config write progbits align=4 section .config.end write nobits align=4 ; 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 write nobits align=16 %if 0 ; IS_PXELINUX ; 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 write nobits RBFG_brainfuck: resb 2048 ; Bigger than an Ethernet packet... %endif section .bss2 write nobits align=16 section .text exec write progbits align=16 section .data write progbits align=16 section .adv write nobits align=512 ; .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 write nobits align=16 ; Normal bss... section .bss1 write nobits align=16 ; Symbols from linker script %macro SECINFO 1 extern __%1_start, __%1_lma, __%1_end extern __%1_len, __%1_dwords %endmacro SECINFO bcopy32 SECINFO config global _start section .text