xref: /linux/arch/m68k/include/uapi/asm/bootinfo.h (revision 4c3c522bcebe16a717d7a809fd14b11823794027)
1 /*
2  * asm/bootinfo.h -- Definition of the Linux/m68k boot information structure
3  *
4  * Copyright 1992 by Greg Harp
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License.  See the file COPYING in the main directory of this archive
8  * for more details.
9  */
10 
11 #ifndef _UAPI_ASM_M68K_BOOTINFO_H
12 #define _UAPI_ASM_M68K_BOOTINFO_H
13 
14 #include <linux/types.h>
15 
16 
17 #ifndef __ASSEMBLY__
18 
19     /*
20      *  Bootinfo definitions
21      *
22      *  This is an easily parsable and extendable structure containing all
23      *  information to be passed from the bootstrap to the kernel.
24      *
25      *  This way I hope to keep all future changes back/forewards compatible.
26      *  Thus, keep your fingers crossed...
27      *
28      *  This structure is copied right after the kernel by the bootstrap
29      *  routine.
30      */
31 
32 struct bi_record {
33 	unsigned short tag;		/* tag ID */
34 	unsigned short size;		/* size of record (in bytes) */
35 	unsigned long data[0];		/* data */
36 };
37 
38 #endif /* __ASSEMBLY__ */
39 
40 
41     /*
42      *  Tag Definitions
43      *
44      *  Machine independent tags start counting from 0x0000
45      *  Machine dependent tags start counting from 0x8000
46      */
47 
48 #define BI_LAST			0x0000	/* last record (sentinel) */
49 #define BI_MACHTYPE		0x0001	/* machine type (u_long) */
50 #define BI_CPUTYPE		0x0002	/* cpu type (u_long) */
51 #define BI_FPUTYPE		0x0003	/* fpu type (u_long) */
52 #define BI_MMUTYPE		0x0004	/* mmu type (u_long) */
53 #define BI_MEMCHUNK		0x0005	/* memory chunk address and size */
54 					/* (struct mem_info) */
55 #define BI_RAMDISK		0x0006	/* ramdisk address and size */
56 					/* (struct mem_info) */
57 #define BI_COMMAND_LINE		0x0007	/* kernel command line parameters */
58 					/* (string) */
59 
60 
61     /*
62      * Stuff for bootinfo interface versioning
63      *
64      * At the start of kernel code, a 'struct bootversion' is located.
65      * bootstrap checks for a matching version of the interface before booting
66      * a kernel, to avoid user confusion if kernel and bootstrap don't work
67      * together :-)
68      *
69      * If incompatible changes are made to the bootinfo interface, the major
70      * number below should be stepped (and the minor reset to 0) for the
71      * appropriate machine. If a change is backward-compatible, the minor
72      * should be stepped. "Backwards-compatible" means that booting will work,
73      * but certain features may not.
74      */
75 
76 #define BOOTINFOV_MAGIC			0x4249561A	/* 'BIV^Z' */
77 #define MK_BI_VERSION(major, minor)	(((major) << 16) + (minor))
78 #define BI_VERSION_MAJOR(v)		(((v) >> 16) & 0xffff)
79 #define BI_VERSION_MINOR(v)		((v) & 0xffff)
80 
81 #ifndef __ASSEMBLY__
82 
83 struct bootversion {
84 	unsigned short branch;
85 	unsigned long magic;
86 	struct {
87 		unsigned long machtype;
88 		unsigned long version;
89 	} machversions[0];
90 } __packed;
91 
92 #endif /* __ASSEMBLY__ */
93 
94 
95 #endif /* _UAPI_ASM_M68K_BOOTINFO_H */
96