xref: /openbmc/u-boot/drivers/bios_emulator/bios.c (revision 415a613b)
1 /****************************************************************************
2 *
3 *                        BIOS emulator and interface
4 *                      to Realmode X86 Emulator Library
5 *
6 *  Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
7 *  Jason Jin <Jason.jin@freescale.com>
8 *
9 *               Copyright (C) 1996-1999 SciTech Software, Inc.
10 *
11 *  ========================================================================
12 *
13 *  Permission to use, copy, modify, distribute, and sell this software and
14 *  its documentation for any purpose is hereby granted without fee,
15 *  provided that the above copyright notice appear in all copies and that
16 *  both that copyright notice and this permission notice appear in
17 *  supporting documentation, and that the name of the authors not be used
18 *  in advertising or publicity pertaining to distribution of the software
19 *  without specific, written prior permission.  The authors makes no
20 *  representations about the suitability of this software for any purpose.
21 *  It is provided "as is" without express or implied warranty.
22 *
23 *  THE AUTHORS DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
24 *  INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
25 *  EVENT SHALL THE AUTHORS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
26 *  CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
27 *  USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
28 *  OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
29 *  PERFORMANCE OF THIS SOFTWARE.
30 *
31 *  ========================================================================
32 *
33 * Language:     ANSI C
34 * Environment:  Any
35 * Developer:    Kendall Bennett
36 *
37 * Description:  Module implementing the BIOS specific functions.
38 *
39 * 		Jason ported this file to u-boot to run the ATI video card
40 * 		video BIOS.
41 *
42 ****************************************************************************/
43 
44 #include <common.h>
45 
46 #if defined(CONFIG_BIOSEMU)
47 
48 #include "biosemui.h"
49 
50 /*----------------------------- Implementation ----------------------------*/
51 
52 /****************************************************************************
53 PARAMETERS:
54 intno   - Interrupt number being serviced
55 
56 REMARKS:
57 Handler for undefined interrupts.
58 ****************************************************************************/
59 static void X86API undefined_intr(int intno)
60 {
61 	if (BE_rdw(intno * 4 + 2) == BIOS_SEG) {
62 		DB(printf("biosEmu: undefined interrupt %xh called!\n", intno);)
63 	} else
64 		X86EMU_prepareForInt(intno);
65 }
66 
67 /****************************************************************************
68 PARAMETERS:
69 intno   - Interrupt number being serviced
70 
71 REMARKS:
72 This function handles the default system BIOS Int 10h (the default is stored
73 in the Int 42h vector by the system BIOS at bootup). We only need to handle
74 a small number of special functions used by the BIOS during POST time.
75 ****************************************************************************/
76 static void X86API int42(int intno)
77 {
78 	if (M.x86.R_AH == 0x12 && M.x86.R_BL == 0x32) {
79 		if (M.x86.R_AL == 0) {
80 			/* Enable CPU accesses to video memory */
81 			PM_outpb(0x3c2, PM_inpb(0x3cc) | (u8) 0x02);
82 			return;
83 		} else if (M.x86.R_AL == 1) {
84 			/* Disable CPU accesses to video memory */
85 			PM_outpb(0x3c2, PM_inpb(0x3cc) & (u8) ~ 0x02);
86 			return;
87 		}
88 #ifdef  DEBUG
89 		else {
90 			printf("int42: unknown function AH=0x12, BL=0x32, AL=%#02x\n",
91 			     M.x86.R_AL);
92 		}
93 #endif
94 	}
95 #ifdef  DEBUG
96 	else {
97 		printf("int42: unknown function AH=%#02x, AL=%#02x, BL=%#02x\n",
98 		     M.x86.R_AH, M.x86.R_AL, M.x86.R_BL);
99 	}
100 #endif
101 }
102 
103 /****************************************************************************
104 PARAMETERS:
105 intno   - Interrupt number being serviced
106 
107 REMARKS:
108 This function handles the default system BIOS Int 10h. If the POST code
109 has not yet re-vectored the Int 10h BIOS interrupt vector, we handle this
110 by simply calling the int42 interrupt handler above. Very early in the
111 BIOS POST process, the vector gets replaced and we simply let the real
112 mode interrupt handler process the interrupt.
113 ****************************************************************************/
114 static void X86API int10(int intno)
115 {
116 	if (BE_rdw(intno * 4 + 2) == BIOS_SEG)
117 		int42(intno);
118 	else
119 		X86EMU_prepareForInt(intno);
120 }
121 
122 /* Result codes returned by the PCI BIOS */
123 
124 #define SUCCESSFUL          0x00
125 #define FUNC_NOT_SUPPORT    0x81
126 #define BAD_VENDOR_ID       0x83
127 #define DEVICE_NOT_FOUND    0x86
128 #define BAD_REGISTER_NUMBER 0x87
129 #define SET_FAILED          0x88
130 #define BUFFER_TOO_SMALL    0x89
131 
132 /****************************************************************************
133 PARAMETERS:
134 intno   - Interrupt number being serviced
135 
136 REMARKS:
137 This function handles the default Int 1Ah interrupt handler for the real
138 mode code, which provides support for the PCI BIOS functions. Since we only
139 want to allow the real mode BIOS code *only* see the PCI config space for
140 its own device, we only return information for the specific PCI config
141 space that we have passed in to the init function. This solves problems
142 when using the BIOS to warm boot a secondary adapter when there is an
143 identical adapter before it on the bus (some BIOS'es get confused in this
144 case).
145 ****************************************************************************/
146 static void X86API int1A(int unused)
147 {
148 	u16 pciSlot;
149 
150 #ifdef __KERNEL__
151 	u8 interface, subclass, baseclass;
152 
153 	/* Initialise the PCI slot number */
154 	pciSlot = ((int)_BE_env.vgaInfo.bus << 8) |
155 	    ((int)_BE_env.vgaInfo.device << 3) | (int)_BE_env.vgaInfo.function;
156 #else
157 /* Fail if no PCI device information has been registered */
158 	if (!_BE_env.vgaInfo.pciInfo)
159 		return;
160 
161 	pciSlot = (u16) (_BE_env.vgaInfo.pciInfo->slot.i >> 8);
162 #endif
163 	switch (M.x86.R_AX) {
164 	case 0xB101:		/* PCI bios present? */
165 		M.x86.R_AL = 0x00;	/* no config space/special cycle generation support */
166 		M.x86.R_EDX = 0x20494350;	/* " ICP" */
167 		M.x86.R_BX = 0x0210;	/* Version 2.10 */
168 		M.x86.R_CL = 0;	/* Max bus number in system */
169 		CLEAR_FLAG(F_CF);
170 		break;
171 	case 0xB102:		/* Find PCI device */
172 		M.x86.R_AH = DEVICE_NOT_FOUND;
173 #ifdef __KERNEL__
174 		if (M.x86.R_DX == _BE_env.vgaInfo.VendorID &&
175 		    M.x86.R_CX == _BE_env.vgaInfo.DeviceID && M.x86.R_SI == 0) {
176 #else
177 		if (M.x86.R_DX == _BE_env.vgaInfo.pciInfo->VendorID &&
178 		    M.x86.R_CX == _BE_env.vgaInfo.pciInfo->DeviceID &&
179 		    M.x86.R_SI == 0) {
180 #endif
181 			M.x86.R_AH = SUCCESSFUL;
182 			M.x86.R_BX = pciSlot;
183 		}
184 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
185 		break;
186 	case 0xB103:		/* Find PCI class code */
187 		M.x86.R_AH = DEVICE_NOT_FOUND;
188 #ifdef __KERNEL__
189 		pci_read_config_byte(_BE_env.vgaInfo.pcidev, PCI_CLASS_PROG,
190 				     &interface);
191 		pci_read_config_byte(_BE_env.vgaInfo.pcidev, PCI_CLASS_DEVICE,
192 				     &subclass);
193 		pci_read_config_byte(_BE_env.vgaInfo.pcidev,
194 				     PCI_CLASS_DEVICE + 1, &baseclass);
195 		if (M.x86.R_CL == interface && M.x86.R_CH == subclass
196 		    && (u8) (M.x86.R_ECX >> 16) == baseclass) {
197 #else
198 		if (M.x86.R_CL == _BE_env.vgaInfo.pciInfo->Interface &&
199 		    M.x86.R_CH == _BE_env.vgaInfo.pciInfo->SubClass &&
200 		    (u8) (M.x86.R_ECX >> 16) ==
201 		    _BE_env.vgaInfo.pciInfo->BaseClass) {
202 #endif
203 			M.x86.R_AH = SUCCESSFUL;
204 			M.x86.R_BX = pciSlot;
205 		}
206 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
207 		break;
208 	case 0xB108:		/* Read configuration byte */
209 		M.x86.R_AH = BAD_REGISTER_NUMBER;
210 		if (M.x86.R_BX == pciSlot) {
211 			M.x86.R_AH = SUCCESSFUL;
212 #ifdef __KERNEL__
213 			pci_read_config_byte(_BE_env.vgaInfo.pcidev, M.x86.R_DI,
214 					     &M.x86.R_CL);
215 #else
216 			M.x86.R_CL =
217 			    (u8) PCI_accessReg(M.x86.R_DI, 0, PCI_READ_BYTE,
218 					       _BE_env.vgaInfo.pciInfo);
219 #endif
220 		}
221 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
222 		break;
223 	case 0xB109:		/* Read configuration word */
224 		M.x86.R_AH = BAD_REGISTER_NUMBER;
225 		if (M.x86.R_BX == pciSlot) {
226 			M.x86.R_AH = SUCCESSFUL;
227 #ifdef __KERNEL__
228 			pci_read_config_word(_BE_env.vgaInfo.pcidev, M.x86.R_DI,
229 					     &M.x86.R_CX);
230 #else
231 			M.x86.R_CX =
232 			    (u16) PCI_accessReg(M.x86.R_DI, 0, PCI_READ_WORD,
233 						_BE_env.vgaInfo.pciInfo);
234 #endif
235 		}
236 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
237 		break;
238 	case 0xB10A:		/* Read configuration dword */
239 		M.x86.R_AH = BAD_REGISTER_NUMBER;
240 		if (M.x86.R_BX == pciSlot) {
241 			M.x86.R_AH = SUCCESSFUL;
242 #ifdef __KERNEL__
243 			pci_read_config_dword(_BE_env.vgaInfo.pcidev,
244 					      M.x86.R_DI, &M.x86.R_ECX);
245 #else
246 			M.x86.R_ECX =
247 			    (u32) PCI_accessReg(M.x86.R_DI, 0, PCI_READ_DWORD,
248 						_BE_env.vgaInfo.pciInfo);
249 #endif
250 		}
251 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
252 		break;
253 	case 0xB10B:		/* Write configuration byte */
254 		M.x86.R_AH = BAD_REGISTER_NUMBER;
255 		if (M.x86.R_BX == pciSlot) {
256 			M.x86.R_AH = SUCCESSFUL;
257 #ifdef __KERNEL__
258 			pci_write_config_byte(_BE_env.vgaInfo.pcidev,
259 					      M.x86.R_DI, M.x86.R_CL);
260 #else
261 			PCI_accessReg(M.x86.R_DI, M.x86.R_CL, PCI_WRITE_BYTE,
262 				      _BE_env.vgaInfo.pciInfo);
263 #endif
264 		}
265 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
266 		break;
267 	case 0xB10C:		/* Write configuration word */
268 		M.x86.R_AH = BAD_REGISTER_NUMBER;
269 		if (M.x86.R_BX == pciSlot) {
270 			M.x86.R_AH = SUCCESSFUL;
271 #ifdef __KERNEL__
272 			pci_write_config_word(_BE_env.vgaInfo.pcidev,
273 					      M.x86.R_DI, M.x86.R_CX);
274 #else
275 			PCI_accessReg(M.x86.R_DI, M.x86.R_CX, PCI_WRITE_WORD,
276 				      _BE_env.vgaInfo.pciInfo);
277 #endif
278 		}
279 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
280 		break;
281 	case 0xB10D:		/* Write configuration dword */
282 		M.x86.R_AH = BAD_REGISTER_NUMBER;
283 		if (M.x86.R_BX == pciSlot) {
284 			M.x86.R_AH = SUCCESSFUL;
285 #ifdef __KERNEL__
286 			pci_write_config_dword(_BE_env.vgaInfo.pcidev,
287 					       M.x86.R_DI, M.x86.R_ECX);
288 #else
289 			PCI_accessReg(M.x86.R_DI, M.x86.R_ECX, PCI_WRITE_DWORD,
290 				      _BE_env.vgaInfo.pciInfo);
291 #endif
292 		}
293 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
294 		break;
295 	default:
296 		printf("biosEmu/bios.int1a: unknown function AX=%#04x\n",
297 		       M.x86.R_AX);
298 	}
299 }
300 
301 /****************************************************************************
302 REMARKS:
303 This function initialises the BIOS emulation functions for the specific
304 PCI display device. We insulate the real mode BIOS from any other devices
305 on the bus, so that it will work correctly thinking that it is the only
306 device present on the bus (ie: avoiding any adapters present in from of
307 the device we are trying to control).
308 ****************************************************************************/
309 #define BE_constLE_32(v)    ((((((v)&0xff00)>>8)|(((v)&0xff)<<8))<<16)|(((((v)&0xff000000)>>8)|(((v)&0x00ff0000)<<8))>>16))
310 
311 void _BE_bios_init(u32 * intrTab)
312 {
313 	int i;
314 	X86EMU_intrFuncs bios_intr_tab[256];
315 
316 	for (i = 0; i < 256; ++i) {
317 		intrTab[i] = BE_constLE_32(BIOS_SEG << 16);
318 		bios_intr_tab[i] = undefined_intr;
319 	}
320 	bios_intr_tab[0x10] = int10;
321 	bios_intr_tab[0x1A] = int1A;
322 	bios_intr_tab[0x42] = int42;
323 	bios_intr_tab[0x6D] = int10;
324 	X86EMU_setupIntrFuncs(bios_intr_tab);
325 }
326 #endif
327