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Diffstat (limited to 'contrib/syslinux-4.02/core/layout.inc')
| -rw-r--r-- | contrib/syslinux-4.02/core/layout.inc | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/core/layout.inc b/contrib/syslinux-4.02/core/layout.inc new file mode 100644 index 0000000..dab27dd --- /dev/null +++ b/contrib/syslinux-4.02/core/layout.inc @@ -0,0 +1,171 @@ +; ----------------------------------------------------------------------- +; +; Copyright 1994-2009 H. Peter Anvin - All Rights Reserved +; Copyright 2009-2010 Intel Corporation; author: H. Peter Anvin +; +; 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 + +; +; 16-bit stack layout +; +; PXELINUX: There are apparently some AMI BIOSes in the field which +; put their BEV stack somewhere below 7C00h (and therefore don't +; handle localboot properly), so avoid that immediate memory region. +; The range that is known to be bad is approximately 75E8..7C00; the +; lower bound is tight. +; + global STACK_LEN, STACK_TOP, STACK_BASE +STACK_LEN equ 4096 +%if IS_PXELINUX +STACK_TOP equ 7000h +%else +STACK_TOP equ 7c00h +%endif +STACK_BASE equ STACK_TOP - STACK_LEN + +; 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 + +; +; 32-bit stack layout +; + global STACK32_LEN +STACK32_LEN equ 64*1024 + + section .stack nobits write align=4096 + resb STACK32_LEN + +; +; The various sections and their relationship +; + ; Use .earlybss for things that MUST be in low memory. + section .earlybss nobits write + section .config write progbits align=4 + section .replacestub exec write progbits align=16 + section .gentextnr exec write nobits align=16 + + ; Use .bss16 for things that doesn't have to be in low memory; + ; .earlybss should be used for things that absolutely have + ; to be below 0x7c00. + section .bss16 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 .init exec write progbits align=1 + section .text16 exec write progbits align=1 + section .textnr exec nowrite progbits align=1 + section .bcopyxx.text exec nowrite progbits align=16 + section .bcopyxx.data noexec write progbits align=16 + section .data16 noexec 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 + + ; Symbols from linker script +%macro SECINFO 1 + extern __%1_start, __%1_lma, __%1_end + extern __%1_len, __%1_dwords +%endmacro + SECINFO bss16 + SECINFO uibss + SECINFO config + SECINFO replacestub + SECINFO bcopyxx + + SECINFO pm_code + SECINFO high_clear + + SECINFO bss + + extern free_high_memory + + global _start + + section .text16 + +; +; Segment assignments in the bottom 640K +; Keep the low-memory footprint as small as possible... overrun is a hard +; failure! +; + +serial_buf_size equ 4096 ; Should be a power of 2 + +; +; Contents of aux_seg +; + extern aux_seg ; Actual segment assigned by linker + + struc aux +.fontbuf resb 8192 +.serial resb serial_buf_size + + alignb 4096 ; Align the next segment to 4K + endstruc + + section .auxseg write nobits align=16 +auxseg resb aux_size + +; +; Transfer buffer segment: guaranteed to be aligned 64K, used for disk I/O +; One symbol for the segment number, one for the absolute address +; + extern xfer_buf_seg + section .xfer_buf write nobits align=65536 + global core_xfer_buf +core_xfer_buf resb 65536 + +; +; Segment for the real mode code (needed as long as we have a in-kernel +; loader and/or COM16 support. +; One symbol for the segment number, one for the absolute address +; + extern real_mode_seg + section .real_mode write nobits align=65536 + global core_real_mode +core_real_mode resb 65536 +comboot_seg equ real_mode_seg ; COMBOOT image loading zone + +; +; At the very end, the lowmem heap +; + extern __lowmem_heap +min_lowmem_heap equ 65536 + + section .text16 |