reactos/boot/freeldr/freeldr/include/arch.h

   1 /*
   2  *  FreeLoader
   3  *  Copyright (C) 1998-2003  Brian Palmer  <brianp@sginet.com>
   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; either version 2 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program; if not, write to the Free Software
  17  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18  */
  19
  20
  21 #ifndef __ARCH_H
  22 #define __ARCH_H
  23
  24 /* Defines needed for switching between real and protected mode */
  25 #define NULL_DESC       0x00    /* NULL descriptor */
  26 #define PMODE_CS        0x08    /* PMode code selector, base 0 limit 4g */
  27 #define PMODE_DS        0x10    /* PMode data selector, base 0 limit 4g */
  28 #define RMODE_CS        0x18    /* RMode code selector, base 0 limit 64k */
  29 #define RMODE_DS        0x20    /* RMode data selector, base 0 limit 64k */
  30
  31 #define CR0_PE_SET      0x00000001      /* OR this value with CR0 to enable pmode */
  32 #define CR0_PE_CLR      0xFFFFFFFE      /* AND this value with CR0 to disable pmode */
  33
  34 #define STACK16ADDR     0x7000  /* The 16-bit stack top will be at 0000:7000 */
  35 #define STACK32ADDR     0x78000 /* The 32-bit stack top will be at 7000:8000, or 0x78000 */
  36
  37 #define BIOSCALLBUFFER          0x78000 /* Buffer to store temporary data for any Int386() call */
  38 #define BIOSCALLBUFSEGMENT      0x7800  /* Buffer to store temporary data for any Int386() call */
  39 #define BIOSCALLBUFOFFSET       0x0000  /* Buffer to store temporary data for any Int386() call */
  40 #define FILESYSBUFFER           0x80000 /* Buffer to store file system data (e.g. cluster buffer for FAT) */
  41 #define DISKREADBUFFER          0x90000 /* Buffer to store data read in from the disk via the BIOS */
  42
  43 /* Makes "x" a global variable or label */
  44 #define EXTERN(x)       .global x; x:
  45
  46
  47
  48
  49 #ifndef ASM
  50
  51
  52 typedef struct
  53 {
  54         unsigned long   eax;
  55         unsigned long   ebx;
  56         unsigned long   ecx;
  57         unsigned long   edx;
  58
  59         unsigned long   esi;
  60         unsigned long   edi;
  61
  62         unsigned short  ds;
  63         unsigned short  es;
  64         unsigned short  fs;
  65         unsigned short  gs;
  66
  67         unsigned long   eflags;
  68
  69 } PACKED DWORDREGS;
  70
  71 typedef struct
  72 {
  73         unsigned short  ax, _upper_ax;
  74         unsigned short  bx, _upper_bx;
  75         unsigned short  cx, _upper_cx;
  76         unsigned short  dx, _upper_dx;
  77
  78         unsigned short  si, _upper_si;
  79         unsigned short  di, _upper_di;
  80
  81         unsigned short  ds;
  82         unsigned short  es;
  83         unsigned short  fs;
  84         unsigned short  gs;
  85
  86         unsigned short  flags, _upper_flags;
  87
  88 } PACKED WORDREGS;
  89
  90 typedef struct
  91 {
  92         unsigned char   al;
  93         unsigned char   ah;
  94         unsigned short  _upper_ax;
  95         unsigned char   bl;
  96         unsigned char   bh;
  97         unsigned short  _upper_bx;
  98         unsigned char   cl;
  99         unsigned char   ch;
 100         unsigned short  _upper_cx;
 101         unsigned char   dl;
 102         unsigned char   dh;
 103         unsigned short  _upper_dx;
 104
 105         unsigned short  si, _upper_si;
 106         unsigned short  di, _upper_di;
 107
 108         unsigned short  ds;
 109         unsigned short  es;
 110         unsigned short  fs;
 111         unsigned short  gs;
 112
 113         unsigned short  flags, _upper_flags;
 114
 115 } PACKED BYTEREGS;
 116
 117 typedef union
 118 {
 119         DWORDREGS       x;
 120         DWORDREGS       d;
 121         WORDREGS        w;
 122         BYTEREGS        b;
 123 } REGS;
 124
 125 // Int386()
 126 //
 127 // Real mode interrupt vector interface
 128 //
 129 // (E)FLAGS can *only* be returned by this function, not set.
 130 // Make sure all memory pointers are in SEG:OFFS format and
 131 // not linear addresses, unless the interrupt handler
 132 // specifically handles linear addresses.
 133 int             Int386(int ivec, REGS* in, REGS* out);
 134
 135 // Flag Masks
 136 #define I386FLAG_CF             0x0001          // Carry Flag
 137 #define I386FLAG_RESV1  0x0002          // Reserved - Must be 1
 138 #define I386FLAG_PF             0x0004          // Parity Flag
 139 #define I386FLAG_RESV2  0x0008          // Reserved - Must be 0
 140 #define I386FLAG_AF             0x0010          // Auxiliary Flag
 141 #define I386FLAG_RESV3  0x0020          // Reserved - Must be 0
 142 #define I386FLAG_ZF             0x0040          // Zero Flag
 143 #define I386FLAG_SF             0x0080          // Sign Flag
 144 #define I386FLAG_TF             0x0100          // Trap Flag (Single Step)
 145 #define I386FLAG_IF             0x0200          // Interrupt Flag
 146 #define I386FLAG_DF             0x0400          // Direction Flag
 147 #define I386FLAG_OF             0x0800          // Overflow Flag
 148
 149 // This macro tests the Carry Flag
 150 // If CF is set then the call failed (usually)
 151 #define INT386_SUCCESS(regs)    ((regs.x.eflags & I386FLAG_CF) == 0)
 152
 153 void    EnableA20(void);
 154
 155 VOID    ChainLoadBiosBootSectorCode(VOID);      // Implemented in boot.S
 156 VOID    SoftReboot(VOID);                                       // Implemented in boot.S
 157
 158 VOID    DetectHardware(VOID);           // Implemented in hardware.c
 159
 160 #endif /* ! ASM */
 161
 162
 163 #endif // #defined __ARCH_H