mkinitrd-magellan/isolinux/layout.inc

; -----------------------------------------------------------------------
;
;   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

;
; 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

;
; The various sections and their relationship
;
		; Use .earlybss for things that MUST be in low memory.
		section .earlybss	nobits
		section .config		write progbits align=4
		section .replacestub	exec write progbits align=16

		; 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 .bcopyxx	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 config
		SECINFO replacestub

		global _start

		section .text

;
; Segment assignments in the bottom 640K
; Keep the low-memory footprint as small as possible... overrun is a hard
; failure!
;
; 0000h - main code/data segment (and BIOS segment)

xfer_buf_seg	equ 1000h
aux_seg		equ 2000h

serial_buf_size	equ 4096		; Should be a power of 2

;
; Contents of aux_seg
;
		struc aux
.fontbuf	resb 8192
.serial		resb serial_buf_size

		alignb 4096		; Align the next segment to 4K
		endstruc

aux_seg_end	equ aux_seg + (aux_size >> 4)

;
; Bounce buffer for I/O to high mem
; Note: we keep all the segments page-aligned, even if that probably
; is somewhat excessive.  Sector alignment is obligatory, however.
;

%if IS_ISOLINUX
; ISOLINUX doesn't have a block cache yet
real_mode_seg	equ aux_seg_end
%else
cache_seg	equ aux_seg_end		; 64K area for metadata cache
real_mode_seg	equ cache_seg + 1000h

pktbuf_seg	equ cache_seg		; PXELINUX packet buffers
%endif

comboot_seg	equ real_mode_seg	; COMBOOT image loading zone
1	; -----------------------------------------------------------------------
2	;
3	; Copyright 1994-2009 H. Peter Anvin - All Rights Reserved
4	; Copyright 2009-2010 Intel Corporation; author: H. Peter Anvin
5	;
6	; This program is free software; you can redistribute it and/or modify
7	; it under the terms of the GNU General Public License as published by
8	; the Free Software Foundation, Inc., 53 Temple Place Ste 330,
9	; Bostom MA 02111-1307, USA; either version 2 of the License, or
10	; (at your option) any later version; incorporated herein by reference.
11	;
12	; -----------------------------------------------------------------------
13
14	;
15	; layout.inc
16	;
17	; Memory layout of segments
18	;
19
20	; Default to 16-bit code
21	bits 16
22
23	; Memory below 0800h is reserved for the BIOS and the MBR.
24	BSS_START equ 0800h
25
26	; Text starts at the load address of 07C00h.
27	TEXT_START equ 7C00h
28
29	;
30	; Stack layout
31	;
32	; PXELINUX: There are apparently some AMI BIOSes in the field which
33	; put their BEV stack somewhere below 7C00h (and therefore don't
34	; handle localboot properly), so avoid that immediate memory region.
35	; The range that is known to be bad is approximately 75E8..7C00; the
36	; lower bound is tight.
37	;
38	global STACK_LEN, STACK_TOP, STACK_BASE
39	STACK_LEN equ 4096
40	%if IS_PXELINUX
41	STACK_TOP equ 7000h
42	%else
43	STACK_TOP equ 7c00h
44	%endif
45	STACK_BASE equ STACK_TOP - STACK_LEN
46
47	; The secondary BSS section, above the text; we really wish we could
48	; just make it follow .bcopy32 or hang off the end,
49	; but it doesn't seem to work that way.
50	LATEBSS_START equ 0B800h
51
52	;
53	; The various sections and their relationship
54	;
55	; Use .earlybss for things that MUST be in low memory.
56	section .earlybss nobits
57	section .config write progbits align=4
58	section .replacestub exec write progbits align=16
59
60	; Use .bss for things that doesn't have to be in low memory;
61	; with .bss1 and .bss2 to offload. .earlybss should be used
62	; for things that absolutely have to be below 0x7c00.
63	section .bss write nobits align=16
64
65	%if 0 ; IS_PXELINUX
66	; Warning here: RBFG build 22 randomly overwrites
67	; memory location [0x5680,0x576c), possibly more. It
68	; seems that it gets confused and screws up the
69	; pointer to its own internal packet buffer and starts
70	; writing a received ARP packet into low memory.
71	section .rbfg write nobits
72	RBFG_brainfuck: resb 2048 ; Bigger than an Ethernet packet...
73	%endif
74
75	section .bss2 write nobits align=16
76
77	section .text exec write progbits align=16
78	section .bcopyxx exec write progbits align=16
79	section .data write progbits align=16
80
81	section .adv write nobits align=512
82
83	; .uibss contains bss data which is guaranteed to be
84	; safe to clobber during the loading of the image. This
85	; is because while loading the primary image we will clobber
86	; the spillover from the last fractional sector load.
87	section .uibss write nobits align=16
88
89	; Normal bss...
90	section .bss1 write nobits align=16
91
92	; Symbols from linker script
93	%macro SECINFO 1
94	extern __%1_start, __%1_lma, __%1_end
95	extern __%1_len, __%1_dwords
96	%endmacro
97	SECINFO config
98	SECINFO replacestub
99
100	global _start
101
102	section .text
103
104	;
105	; Segment assignments in the bottom 640K
106	; Keep the low-memory footprint as small as possible... overrun is a hard
107	; failure!
108	;
109	; 0000h - main code/data segment (and BIOS segment)
110
111	xfer_buf_seg equ 1000h
112	aux_seg equ 2000h
113
114	serial_buf_size equ 4096 ; Should be a power of 2
115
116	;
117	; Contents of aux_seg
118	;
119	struc aux
120	.fontbuf resb 8192
121	.serial resb serial_buf_size
122
123	alignb 4096 ; Align the next segment to 4K
124	endstruc
125
126	aux_seg_end equ aux_seg + (aux_size >> 4)
127
128	;
129	; Bounce buffer for I/O to high mem
130	; Note: we keep all the segments page-aligned, even if that probably
131	; is somewhat excessive. Sector alignment is obligatory, however.
132	;
133
134	%if IS_ISOLINUX
135	; ISOLINUX doesn't have a block cache yet
136	real_mode_seg equ aux_seg_end
137	%else
138	cache_seg equ aux_seg_end ; 64K area for metadata cache
139	real_mode_seg equ cache_seg + 1000h
140
141	pktbuf_seg equ cache_seg ; PXELINUX packet buffers
142	%endif
143
144	comboot_seg equ real_mode_seg ; COMBOOT image loading zone