drivers/bios_emulator/x86emu/sys.c

   1 /****************************************************************************
   2 *
   3 *                       Realmode X86 Emulator Library
   4 *
   5 *               Copyright (C) 1991-2004 SciTech Software, Inc.
   6 *                    Copyright (C) David Mosberger-Tang
   7 *                      Copyright (C) 1999 Egbert Eich
   8 *
   9 *  ========================================================================
  10 *
  11 *  Permission to use, copy, modify, distribute, and sell this software and
  12 *  its documentation for any purpose is hereby granted without fee,
  13 *  provided that the above copyright notice appear in all copies and that
  14 *  both that copyright notice and this permission notice appear in
  15 *  supporting documentation, and that the name of the authors not be used
  16 *  in advertising or publicity pertaining to distribution of the software
  17 *  without specific, written prior permission.  The authors makes no
  18 *  representations about the suitability of this software for any purpose.
  19 *  It is provided "as is" without express or implied warranty.
  20 *
  21 *  THE AUTHORS DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  22 *  INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  23 *  EVENT SHALL THE AUTHORS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  24 *  CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
  25 *  USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
  26 *  OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  27 *  PERFORMANCE OF THIS SOFTWARE.
  28 *
  29 *  ========================================================================
  30 *
  31 * Language:     ANSI C
  32 * Environment:  Any
  33 * Developer:    Kendall Bennett
  34 *
  35 * Description:  This file includes subroutines which are related to
  36 *               programmed I/O and memory access. Included in this module
  37 *               are default functions that do nothing. For real uses these
  38 *               functions will have to be overriden by the user library.
  39 *
  40 ****************************************************************************/
  41
  42 #include <common.h>
  43 #include "x86emu/x86emui.h"
  44
  45 /*------------------------- Global Variables ------------------------------*/
  46
  47 X86EMU_sysEnv _X86EMU_env;      /* Global emulator machine state */
  48 X86EMU_intrFuncs _X86EMU_intrTab[256];
  49
  50 int debug_intr;
  51
  52 /*----------------------------- Implementation ----------------------------*/
  53
  54 /****************************************************************************
  55 PARAMETERS:
  56 addr    - Emulator memory address to read
  57
  58 RETURNS:
  59 Byte value read from emulator memory.
  60
  61 REMARKS:
  62 Reads a byte value from the emulator memory.
  63 ****************************************************************************/
  64 u8 X86API rdb(u32 addr)
  65 {
  66         return 0;
  67 }
  68
  69 /****************************************************************************
  70 PARAMETERS:
  71 addr    - Emulator memory address to read
  72
  73 RETURNS:
  74 Word value read from emulator memory.
  75
  76 REMARKS:
  77 Reads a word value from the emulator memory.
  78 ****************************************************************************/
  79 u16 X86API rdw(u32 addr)
  80 {
  81         return 0;
  82 }
  83
  84 /****************************************************************************
  85 PARAMETERS:
  86 addr    - Emulator memory address to read
  87
  88 RETURNS:
  89 Long value read from emulator memory.
  90 REMARKS:
  91 Reads a long value from the emulator memory.
  92 ****************************************************************************/
  93 u32 X86API rdl(u32 addr)
  94 {
  95         return 0;
  96 }
  97
  98 /****************************************************************************
  99 PARAMETERS:
 100 addr    - Emulator memory address to read
 101 val     - Value to store
 102
 103 REMARKS:
 104 Writes a byte value to emulator memory.
 105 ****************************************************************************/
 106 void X86API wrb(u32 addr, u8 val)
 107 {
 108 }
 109
 110 /****************************************************************************
 111 PARAMETERS:
 112 addr    - Emulator memory address to read
 113 val     - Value to store
 114
 115 REMARKS:
 116 Writes a word value to emulator memory.
 117 ****************************************************************************/
 118 void X86API wrw(u32 addr, u16 val)
 119 {
 120 }
 121
 122 /****************************************************************************
 123 PARAMETERS:
 124 addr    - Emulator memory address to read
 125 val     - Value to store
 126
 127 REMARKS:
 128 Writes a long value to emulator memory.
 129 ****************************************************************************/
 130 void X86API wrl(u32 addr, u32 val)
 131 {
 132 }
 133
 134 /****************************************************************************
 135 PARAMETERS:
 136 addr    - PIO address to read
 137 RETURN:
 138 0
 139 REMARKS:
 140 Default PIO byte read function. Doesn't perform real inb.
 141 ****************************************************************************/
 142 static u8 X86API p_inb(X86EMU_pioAddr addr)
 143 {
 144         DB(if (DEBUG_IO_TRACE())
 145            printk("inb %#04x \n", addr);)
 146                 return 0;
 147 }
 148
 149 /****************************************************************************
 150 PARAMETERS:
 151 addr    - PIO address to read
 152 RETURN:
 153 0
 154 REMARKS:
 155 Default PIO word read function. Doesn't perform real inw.
 156 ****************************************************************************/
 157 static u16 X86API p_inw(X86EMU_pioAddr addr)
 158 {
 159         DB(if (DEBUG_IO_TRACE())
 160            printk("inw %#04x \n", addr);)
 161                 return 0;
 162 }
 163
 164 /****************************************************************************
 165 PARAMETERS:
 166 addr    - PIO address to read
 167 RETURN:
 168 0
 169 REMARKS:
 170 Default PIO long read function. Doesn't perform real inl.
 171 ****************************************************************************/
 172 static u32 X86API p_inl(X86EMU_pioAddr addr)
 173 {
 174         DB(if (DEBUG_IO_TRACE())
 175            printk("inl %#04x \n", addr);)
 176                 return 0;
 177 }
 178
 179 /****************************************************************************
 180 PARAMETERS:
 181 addr    - PIO address to write
 182 val     - Value to store
 183 REMARKS:
 184 Default PIO byte write function. Doesn't perform real outb.
 185 ****************************************************************************/
 186 static void X86API p_outb(X86EMU_pioAddr addr, u8 val)
 187 {
 188         DB(if (DEBUG_IO_TRACE())
 189            printk("outb %#02x -> %#04x \n", val, addr);)
 190                 return;
 191 }
 192
 193 /****************************************************************************
 194 PARAMETERS:
 195 addr    - PIO address to write
 196 val     - Value to store
 197 REMARKS:
 198 Default PIO word write function. Doesn't perform real outw.
 199 ****************************************************************************/
 200 static void X86API p_outw(X86EMU_pioAddr addr, u16 val)
 201 {
 202         DB(if (DEBUG_IO_TRACE())
 203            printk("outw %#04x -> %#04x \n", val, addr);)
 204                 return;
 205 }
 206
 207 /****************************************************************************
 208 PARAMETERS:
 209 addr    - PIO address to write
 210 val     - Value to store
 211 REMARKS:
 212 Default PIO ;ong write function. Doesn't perform real outl.
 213 ****************************************************************************/
 214 static void X86API p_outl(X86EMU_pioAddr addr, u32 val)
 215 {
 216         DB(if (DEBUG_IO_TRACE())
 217            printk("outl %#08x -> %#04x \n", val, addr);)
 218                 return;
 219 }
 220
 221 /*------------------------- Global Variables ------------------------------*/
 222
 223 u8(X86APIP sys_rdb) (u32 addr) = rdb;
 224 u16(X86APIP sys_rdw) (u32 addr) = rdw;
 225 u32(X86APIP sys_rdl) (u32 addr) = rdl;
 226 void (X86APIP sys_wrb) (u32 addr, u8 val) = wrb;
 227 void (X86APIP sys_wrw) (u32 addr, u16 val) = wrw;
 228 void (X86APIP sys_wrl) (u32 addr, u32 val) = wrl;
 229 u8(X86APIP sys_inb) (X86EMU_pioAddr addr) = p_inb;
 230 u16(X86APIP sys_inw) (X86EMU_pioAddr addr) = p_inw;
 231 u32(X86APIP sys_inl) (X86EMU_pioAddr addr) = p_inl;
 232 void (X86APIP sys_outb) (X86EMU_pioAddr addr, u8 val) = p_outb;
 233 void (X86APIP sys_outw) (X86EMU_pioAddr addr, u16 val) = p_outw;
 234 void (X86APIP sys_outl) (X86EMU_pioAddr addr, u32 val) = p_outl;
 235
 236 /*----------------------------- Setup -------------------------------------*/
 237
 238 /****************************************************************************
 239 PARAMETERS:
 240 funcs   - New memory function pointers to make active
 241
 242 REMARKS:
 243 This function is used to set the pointers to functions which access
 244 memory space, allowing the user application to override these functions
 245 and hook them out as necessary for their application.
 246 ****************************************************************************/
 247 void X86EMU_setupMemFuncs(X86EMU_memFuncs * funcs)
 248 {
 249         sys_rdb = funcs->rdb;
 250         sys_rdw = funcs->rdw;
 251         sys_rdl = funcs->rdl;
 252         sys_wrb = funcs->wrb;
 253         sys_wrw = funcs->wrw;
 254         sys_wrl = funcs->wrl;
 255 }
 256
 257 /****************************************************************************
 258 PARAMETERS:
 259 funcs   - New programmed I/O function pointers to make active
 260
 261 REMARKS:
 262 This function is used to set the pointers to functions which access
 263 I/O space, allowing the user application to override these functions
 264 and hook them out as necessary for their application.
 265 ****************************************************************************/
 266 void X86EMU_setupPioFuncs(X86EMU_pioFuncs * funcs)
 267 {
 268         sys_inb = funcs->inb;
 269         sys_inw = funcs->inw;
 270         sys_inl = funcs->inl;
 271         sys_outb = funcs->outb;
 272         sys_outw = funcs->outw;
 273         sys_outl = funcs->outl;
 274 }
 275
 276 /****************************************************************************
 277 PARAMETERS:
 278 funcs   - New interrupt vector table to make active
 279
 280 REMARKS:
 281 This function is used to set the pointers to functions which handle
 282 interrupt processing in the emulator, allowing the user application to
 283 hook interrupts as necessary for their application. Any interrupts that
 284 are not hooked by the user application, and reflected and handled internally
 285 in the emulator via the interrupt vector table. This allows the application
 286 to get control when the code being emulated executes specific software
 287 interrupts.
 288 ****************************************************************************/
 289 void X86EMU_setupIntrFuncs(X86EMU_intrFuncs funcs[])
 290 {
 291         int i;
 292
 293         for (i = 0; i < 256; i++)
 294                 _X86EMU_intrTab[i] = NULL;
 295         if (funcs) {
 296                 for (i = 0; i < 256; i++)
 297                         _X86EMU_intrTab[i] = funcs[i];
 298         }
 299 }
 300
 301 /****************************************************************************
 302 PARAMETERS:
 303 int - New software interrupt to prepare for
 304
 305 REMARKS:
 306 This function is used to set up the emulator state to exceute a software
 307 interrupt. This can be used by the user application code to allow an
 308 interrupt to be hooked, examined and then reflected back to the emulator
 309 so that the code in the emulator will continue processing the software
 310 interrupt as per normal. This essentially allows system code to actively
 311 hook and handle certain software interrupts as necessary.
 312 ****************************************************************************/
 313 void X86EMU_prepareForInt(int num)
 314 {
 315         push_word((u16) M.x86.R_FLG);
 316         CLEAR_FLAG(F_IF);
 317         CLEAR_FLAG(F_TF);
 318         push_word(M.x86.R_CS);
 319         M.x86.R_CS = mem_access_word(num * 4 + 2);
 320         push_word(M.x86.R_IP);
 321         M.x86.R_IP = mem_access_word(num * 4);
 322         M.x86.intr = 0;
 323 }