memdisk/memdisk.h

   1 /* ----------------------------------------------------------------------- *
   2  *
   3  *   Copyright 2001-2008 H. Peter Anvin - All Rights Reserved
   4  *
   5  *   This program is free software; you can redistribute it and/or modify
   6  *   it under the terms of the GNU General Public License as published by
   7  *   the Free Software Foundation, Inc., 53 Temple Place Ste 330,
   8  *   Boston MA 02111-1307, USA; either version 2 of the License, or
   9  *   (at your option) any later version; incorporated herein by reference.
  10  *
  11  * ----------------------------------------------------------------------- */
  12
  13 /*
  14  * memdisk.h
  15  *
  16  * Miscellaneous header definitions
  17  */
  18
  19 #ifndef MEMDISK_H
  20 #define MEMDISK_H
  21
  22 #include <stddef.h>
  23
  24 /* We use the com32 interface for calling 16-bit code */
  25 #include <com32.h>
  26
  27 #define __cdecl __attribute__((cdecl,regparm(0)))
  28
  29 void __cdecl intcall(uint8_t, com32sys_t *, com32sys_t *);
  30
  31 /* Structure passed in from the real-mode code */
  32 struct real_mode_args {
  33     uint32_t rm_return;
  34     uint32_t rm_intcall;
  35     uint32_t rm_bounce;
  36     uint32_t rm_base;
  37     uint32_t rm_handle_interrupt;
  38     uint32_t rm_gdt;
  39     uint32_t rm_size;
  40     uint32_t rm_pmjmp;
  41     uint32_t rm_rmjmp;
  42 };
  43 extern struct real_mode_args rm_args;
  44 #define sys_bounce ((void *)rm_args.rm_bounce)
  45
  46 /* This is the header in the boot sector/setup area */
  47 struct setup_header {
  48     char cmdline[0x1f1];
  49     uint8_t setup_secs;
  50     uint16_t syssize;
  51     uint16_t swap_dev;
  52     uint16_t ram_size;
  53     uint16_t vid_mode;
  54     uint16_t root_dev;
  55     uint16_t boot_flag;
  56     uint16_t jump;
  57     char header[4];
  58     uint16_t version;
  59     uint32_t realmode_swtch;
  60     uint32_t start_sys;
  61     uint8_t type_of_loader;
  62     uint8_t loadflags;
  63     uint16_t setup_move_size;
  64     uint32_t code32_start;
  65     uint32_t ramdisk_image;
  66     uint32_t ramdisk_size;
  67     uint32_t bootsect_kludge;
  68     uint16_t head_end_ptr;
  69     uint16_t pad1;
  70     uint32_t cmd_line_ptr;
  71     uint32_t initrd_addr_max;
  72     uint32_t esdi;
  73     uint32_t edx;
  74     uint32_t sssp;
  75     uint32_t csip;
  76 };
  77 #define shdr ((struct setup_header *)rm_args.rm_base)
  78
  79 /* Standard routines */
  80 void *memcpy(void *, const void *, size_t);
  81 void *memset(void *, int, size_t);
  82 void *memmove(void *, const void *, size_t);
  83
  84 #define strcpy(a,b)   __builtin_strcpy(a,b)
  85
  86 static inline size_t strlen(const char *__a)
  87 {
  88     const char *__D;
  89     size_t __c;
  90
  91 asm("repne;scasb":"=D"(__D), "=c"(__c)
  92 :       "D"(__a), "c"(-1), "a"(0), "m"(*__a));
  93
  94     return __D - __a - 1;
  95 }
  96
  97 /* memcpy() but returns a pointer to end of buffer */
  98 static inline void *mempcpy(void *__d, const void *__s, unsigned int __n)
  99 {
 100     memcpy(__d, __s, __n);
 101     return (void *)((char *)__d + __n);
 102 }
 103
 104 /* memcmp() */
 105 static inline int memcmp(const void *__a, const void *__b, unsigned int __n)
 106 {
 107     const unsigned char *__aa = __a;
 108     const unsigned char *__bb = __b;
 109     int __d;
 110
 111     while (__n--) {
 112         __d = *__bb++ - *__aa++;
 113         if (__d)
 114             return __d;
 115     }
 116
 117     return 0;
 118 }
 119
 120 static inline void sti(void)
 121 {
 122     asm volatile("sti");
 123 }
 124
 125 static inline void cli(void)
 126 {
 127     asm volatile("cli");
 128 }
 129
 130 /* Decompression */
 131 extern int check_zip(void *indata, uint32_t size, uint32_t * zbytes_p,
 132                      uint32_t * dbytes_p, uint32_t * orig_crc,
 133                      uint32_t * offset_p);
 134 extern void *unzip(void *indata, uint32_t zbytes, uint32_t dbytes,
 135                    uint32_t orig_crc, void *target);
 136
 137 #endif