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 overridden by the user library.
39 *
40 ****************************************************************************/
41 
42 #include <linux/printk.h>
43 #include "x86emu/x86emui.h"
44 
45 /*------------------------- Global Variables ------------------------------*/
46 
47 /* Note: bios.c defines this if the emulator is not enabled */
48 X86EMU_sysEnv _X86EMU_env;	/* Global emulator machine state */
49 X86EMU_intrFuncs _X86EMU_intrTab[256];
50 
51 int debug_intr;
52 
53 /*----------------------------- Implementation ----------------------------*/
54 
55 /****************************************************************************
56 PARAMETERS:
57 addr    - Emulator memory address to read
58 
59 RETURNS:
60 Byte value read from emulator memory.
61 
62 REMARKS:
63 Reads a byte value from the emulator memory.
64 ****************************************************************************/
rdb(u32 addr)65 u8 X86API rdb(u32 addr)
66 {
67 	return 0;
68 }
69 
70 /****************************************************************************
71 PARAMETERS:
72 addr    - Emulator memory address to read
73 
74 RETURNS:
75 Word value read from emulator memory.
76 
77 REMARKS:
78 Reads a word value from the emulator memory.
79 ****************************************************************************/
rdw(u32 addr)80 u16 X86API rdw(u32 addr)
81 {
82 	return 0;
83 }
84 
85 /****************************************************************************
86 PARAMETERS:
87 addr    - Emulator memory address to read
88 
89 RETURNS:
90 Long value read from emulator memory.
91 REMARKS:
92 Reads a long value from the emulator memory.
93 ****************************************************************************/
rdl(u32 addr)94 u32 X86API rdl(u32 addr)
95 {
96 	return 0;
97 }
98 
99 /****************************************************************************
100 PARAMETERS:
101 addr    - Emulator memory address to read
102 val     - Value to store
103 
104 REMARKS:
105 Writes a byte value to emulator memory.
106 ****************************************************************************/
wrb(u32 addr,u8 val)107 void X86API wrb(u32 addr, u8 val)
108 {
109 }
110 
111 /****************************************************************************
112 PARAMETERS:
113 addr    - Emulator memory address to read
114 val     - Value to store
115 
116 REMARKS:
117 Writes a word value to emulator memory.
118 ****************************************************************************/
wrw(u32 addr,u16 val)119 void X86API wrw(u32 addr, u16 val)
120 {
121 }
122 
123 /****************************************************************************
124 PARAMETERS:
125 addr    - Emulator memory address to read
126 val     - Value to store
127 
128 REMARKS:
129 Writes a long value to emulator memory.
130 ****************************************************************************/
wrl(u32 addr,u32 val)131 void X86API wrl(u32 addr, u32 val)
132 {
133 }
134 
135 /****************************************************************************
136 PARAMETERS:
137 addr    - PIO address to read
138 RETURN:
139 0
140 REMARKS:
141 Default PIO byte read function. Doesn't perform real inb.
142 ****************************************************************************/
p_inb(X86EMU_pioAddr addr)143 static u8 X86API p_inb(X86EMU_pioAddr addr)
144 {
145 	DB(if (DEBUG_IO_TRACE())
146 	   printk("inb %#04x \n", addr);)
147 		return 0;
148 }
149 
150 /****************************************************************************
151 PARAMETERS:
152 addr    - PIO address to read
153 RETURN:
154 0
155 REMARKS:
156 Default PIO word read function. Doesn't perform real inw.
157 ****************************************************************************/
p_inw(X86EMU_pioAddr addr)158 static u16 X86API p_inw(X86EMU_pioAddr addr)
159 {
160 	DB(if (DEBUG_IO_TRACE())
161 	   printk("inw %#04x \n", addr);)
162 		return 0;
163 }
164 
165 /****************************************************************************
166 PARAMETERS:
167 addr    - PIO address to read
168 RETURN:
169 0
170 REMARKS:
171 Default PIO long read function. Doesn't perform real inl.
172 ****************************************************************************/
p_inl(X86EMU_pioAddr addr)173 static u32 X86API p_inl(X86EMU_pioAddr addr)
174 {
175 	DB(if (DEBUG_IO_TRACE())
176 	   printk("inl %#04x \n", addr);)
177 		return 0;
178 }
179 
180 /****************************************************************************
181 PARAMETERS:
182 addr    - PIO address to write
183 val     - Value to store
184 REMARKS:
185 Default PIO byte write function. Doesn't perform real outb.
186 ****************************************************************************/
p_outb(X86EMU_pioAddr addr,u8 val)187 static void X86API p_outb(X86EMU_pioAddr addr, u8 val)
188 {
189 	DB(if (DEBUG_IO_TRACE())
190 	   printk("outb %#02x -> %#04x \n", val, addr);)
191 		return;
192 }
193 
194 /****************************************************************************
195 PARAMETERS:
196 addr    - PIO address to write
197 val     - Value to store
198 REMARKS:
199 Default PIO word write function. Doesn't perform real outw.
200 ****************************************************************************/
p_outw(X86EMU_pioAddr addr,u16 val)201 static void X86API p_outw(X86EMU_pioAddr addr, u16 val)
202 {
203 	DB(if (DEBUG_IO_TRACE())
204 	   printk("outw %#04x -> %#04x \n", val, addr);)
205 		return;
206 }
207 
208 /****************************************************************************
209 PARAMETERS:
210 addr    - PIO address to write
211 val     - Value to store
212 REMARKS:
213 Default PIO ;ong write function. Doesn't perform real outl.
214 ****************************************************************************/
p_outl(X86EMU_pioAddr addr,u32 val)215 static void X86API p_outl(X86EMU_pioAddr addr, u32 val)
216 {
217 	DB(if (DEBUG_IO_TRACE())
218 	   printk("outl %#08x -> %#04x \n", val, addr);)
219 		return;
220 }
221 
222 /*------------------------- Global Variables ------------------------------*/
223 
224 u8(X86APIP sys_rdb) (u32 addr) = rdb;
225 u16(X86APIP sys_rdw) (u32 addr) = rdw;
226 u32(X86APIP sys_rdl) (u32 addr) = rdl;
227 void (X86APIP sys_wrb) (u32 addr, u8 val) = wrb;
228 void (X86APIP sys_wrw) (u32 addr, u16 val) = wrw;
229 void (X86APIP sys_wrl) (u32 addr, u32 val) = wrl;
230 u8(X86APIP sys_inb) (X86EMU_pioAddr addr) = p_inb;
231 u16(X86APIP sys_inw) (X86EMU_pioAddr addr) = p_inw;
232 u32(X86APIP sys_inl) (X86EMU_pioAddr addr) = p_inl;
233 void (X86APIP sys_outb) (X86EMU_pioAddr addr, u8 val) = p_outb;
234 void (X86APIP sys_outw) (X86EMU_pioAddr addr, u16 val) = p_outw;
235 void (X86APIP sys_outl) (X86EMU_pioAddr addr, u32 val) = p_outl;
236 
237 /*----------------------------- Setup -------------------------------------*/
238 
239 /****************************************************************************
240 PARAMETERS:
241 funcs   - New memory function pointers to make active
242 
243 REMARKS:
244 This function is used to set the pointers to functions which access
245 memory space, allowing the user application to override these functions
246 and hook them out as necessary for their application.
247 ****************************************************************************/
X86EMU_setupMemFuncs(X86EMU_memFuncs * funcs)248 void X86EMU_setupMemFuncs(X86EMU_memFuncs * funcs)
249 {
250 	sys_rdb = funcs->rdb;
251 	sys_rdw = funcs->rdw;
252 	sys_rdl = funcs->rdl;
253 	sys_wrb = funcs->wrb;
254 	sys_wrw = funcs->wrw;
255 	sys_wrl = funcs->wrl;
256 }
257 
258 /****************************************************************************
259 PARAMETERS:
260 funcs   - New programmed I/O function pointers to make active
261 
262 REMARKS:
263 This function is used to set the pointers to functions which access
264 I/O space, allowing the user application to override these functions
265 and hook them out as necessary for their application.
266 ****************************************************************************/
X86EMU_setupPioFuncs(X86EMU_pioFuncs * funcs)267 void X86EMU_setupPioFuncs(X86EMU_pioFuncs * funcs)
268 {
269 	sys_inb = funcs->inb;
270 	sys_inw = funcs->inw;
271 	sys_inl = funcs->inl;
272 	sys_outb = funcs->outb;
273 	sys_outw = funcs->outw;
274 	sys_outl = funcs->outl;
275 }
276 
X86EMU_setupIntrFunc(int intnum,X86EMU_intrFuncs func)277 void X86EMU_setupIntrFunc(int intnum, X86EMU_intrFuncs func)
278 {
279 	_X86EMU_intrTab[intnum] = func;
280 }
281 
282 /****************************************************************************
283 PARAMETERS:
284 funcs   - New interrupt vector table to make active
285 
286 REMARKS:
287 This function is used to set the pointers to functions which handle
288 interrupt processing in the emulator, allowing the user application to
289 hook interrupts as necessary for their application. Any interrupts that
290 are not hooked by the user application, and reflected and handled internally
291 in the emulator via the interrupt vector table. This allows the application
292 to get control when the code being emulated executes specific software
293 interrupts.
294 ****************************************************************************/
X86EMU_setupIntrFuncs(X86EMU_intrFuncs funcs[])295 void X86EMU_setupIntrFuncs(X86EMU_intrFuncs funcs[])
296 {
297 	int i;
298 
299 	for (i = 0; i < 256; i++)
300 		_X86EMU_intrTab[i] = NULL;
301 	if (funcs) {
302 		for (i = 0; i < 256; i++)
303 			_X86EMU_intrTab[i] = funcs[i];
304 	}
305 }
306 
307 /****************************************************************************
308 PARAMETERS:
309 int - New software interrupt to prepare for
310 
311 REMARKS:
312 This function is used to set up the emulator state to exceute a software
313 interrupt. This can be used by the user application code to allow an
314 interrupt to be hooked, examined and then reflected back to the emulator
315 so that the code in the emulator will continue processing the software
316 interrupt as per normal. This essentially allows system code to actively
317 hook and handle certain software interrupts as necessary.
318 ****************************************************************************/
X86EMU_prepareForInt(int num)319 void X86EMU_prepareForInt(int num)
320 {
321 	push_word((u16) M.x86.R_FLG);
322 	CLEAR_FLAG(F_IF);
323 	CLEAR_FLAG(F_TF);
324 	push_word(M.x86.R_CS);
325 	M.x86.R_CS = mem_access_word(num * 4 + 2);
326 	push_word(M.x86.R_IP);
327 	M.x86.R_IP = mem_access_word(num * 4);
328 	M.x86.intr = 0;
329 }
330