xref: /openbmc/u-boot/drivers/bios_emulator/bios.c (revision 15855700)
1 /****************************************************************************
2 *
3 *                        BIOS emulator and interface
4 *                      to Realmode X86 Emulator Library
5 *
6 *  Copyright (C) 2007 Freescale Semiconductor, Inc.
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 #include "biosemui.h"
46 
47 /*----------------------------- Implementation ----------------------------*/
48 
49 /****************************************************************************
50 PARAMETERS:
51 intno   - Interrupt number being serviced
52 
53 REMARKS:
54 Handler for undefined interrupts.
55 ****************************************************************************/
56 static void X86API undefined_intr(int intno)
57 {
58 	if (BE_rdw(intno * 4 + 2) == BIOS_SEG) {
59 		DB(printf("biosEmu: undefined interrupt %xh called!\n", intno);)
60 	} else
61 		X86EMU_prepareForInt(intno);
62 }
63 
64 /****************************************************************************
65 PARAMETERS:
66 intno   - Interrupt number being serviced
67 
68 REMARKS:
69 This function handles the default system BIOS Int 10h (the default is stored
70 in the Int 42h vector by the system BIOS at bootup). We only need to handle
71 a small number of special functions used by the BIOS during POST time.
72 ****************************************************************************/
73 static void X86API int42(int intno)
74 {
75 	if (M.x86.R_AH == 0x12 && M.x86.R_BL == 0x32) {
76 		if (M.x86.R_AL == 0) {
77 			/* Enable CPU accesses to video memory */
78 			PM_outpb(0x3c2, PM_inpb(0x3cc) | (u8) 0x02);
79 			return;
80 		} else if (M.x86.R_AL == 1) {
81 			/* Disable CPU accesses to video memory */
82 			PM_outpb(0x3c2, PM_inpb(0x3cc) & (u8) ~ 0x02);
83 			return;
84 		}
85 #ifdef  DEBUG
86 		else {
87 			printf("int42: unknown function AH=0x12, BL=0x32, AL=%#02x\n",
88 			     M.x86.R_AL);
89 		}
90 #endif
91 	}
92 #ifdef  DEBUG
93 	else {
94 		printf("int42: unknown function AH=%#02x, AL=%#02x, BL=%#02x\n",
95 		     M.x86.R_AH, M.x86.R_AL, M.x86.R_BL);
96 	}
97 #endif
98 }
99 
100 /****************************************************************************
101 PARAMETERS:
102 intno   - Interrupt number being serviced
103 
104 REMARKS:
105 This function handles the default system BIOS Int 10h. If the POST code
106 has not yet re-vectored the Int 10h BIOS interrupt vector, we handle this
107 by simply calling the int42 interrupt handler above. Very early in the
108 BIOS POST process, the vector gets replaced and we simply let the real
109 mode interrupt handler process the interrupt.
110 ****************************************************************************/
111 static void X86API int10(int intno)
112 {
113 	if (BE_rdw(intno * 4 + 2) == BIOS_SEG)
114 		int42(intno);
115 	else
116 		X86EMU_prepareForInt(intno);
117 }
118 
119 /* Result codes returned by the PCI BIOS */
120 
121 #define SUCCESSFUL          0x00
122 #define FUNC_NOT_SUPPORT    0x81
123 #define BAD_VENDOR_ID       0x83
124 #define DEVICE_NOT_FOUND    0x86
125 #define BAD_REGISTER_NUMBER 0x87
126 #define SET_FAILED          0x88
127 #define BUFFER_TOO_SMALL    0x89
128 
129 /****************************************************************************
130 PARAMETERS:
131 intno   - Interrupt number being serviced
132 
133 REMARKS:
134 This function handles the default Int 1Ah interrupt handler for the real
135 mode code, which provides support for the PCI BIOS functions. Since we only
136 want to allow the real mode BIOS code *only* see the PCI config space for
137 its own device, we only return information for the specific PCI config
138 space that we have passed in to the init function. This solves problems
139 when using the BIOS to warm boot a secondary adapter when there is an
140 identical adapter before it on the bus (some BIOS'es get confused in this
141 case).
142 ****************************************************************************/
143 static void X86API int1A(int unused)
144 {
145 	u16 pciSlot;
146 
147 #ifdef __KERNEL__
148 	u8 interface, subclass, baseclass;
149 
150 	/* Initialise the PCI slot number */
151 	pciSlot = ((int)_BE_env.vgaInfo.bus << 8) |
152 	    ((int)_BE_env.vgaInfo.device << 3) | (int)_BE_env.vgaInfo.function;
153 #else
154 /* Fail if no PCI device information has been registered */
155 	if (!_BE_env.vgaInfo.pciInfo)
156 		return;
157 
158 	pciSlot = (u16) (_BE_env.vgaInfo.pciInfo->slot.i >> 8);
159 #endif
160 	switch (M.x86.R_AX) {
161 	case 0xB101:		/* PCI bios present? */
162 		M.x86.R_AL = 0x00;	/* no config space/special cycle generation support */
163 		M.x86.R_EDX = 0x20494350;	/* " ICP" */
164 		M.x86.R_BX = 0x0210;	/* Version 2.10 */
165 		M.x86.R_CL = 0;	/* Max bus number in system */
166 		CLEAR_FLAG(F_CF);
167 		break;
168 	case 0xB102:		/* Find PCI device */
169 		M.x86.R_AH = DEVICE_NOT_FOUND;
170 #ifdef __KERNEL__
171 		if (M.x86.R_DX == _BE_env.vgaInfo.VendorID &&
172 		    M.x86.R_CX == _BE_env.vgaInfo.DeviceID && M.x86.R_SI == 0) {
173 #else
174 		if (M.x86.R_DX == _BE_env.vgaInfo.pciInfo->VendorID &&
175 		    M.x86.R_CX == _BE_env.vgaInfo.pciInfo->DeviceID &&
176 		    M.x86.R_SI == 0) {
177 #endif
178 			M.x86.R_AH = SUCCESSFUL;
179 			M.x86.R_BX = pciSlot;
180 		}
181 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
182 		break;
183 	case 0xB103:		/* Find PCI class code */
184 		M.x86.R_AH = DEVICE_NOT_FOUND;
185 #ifdef __KERNEL__
186 		pci_read_config_byte(_BE_env.vgaInfo.pcidev, PCI_CLASS_PROG,
187 				     &interface);
188 		pci_read_config_byte(_BE_env.vgaInfo.pcidev, PCI_CLASS_DEVICE,
189 				     &subclass);
190 		pci_read_config_byte(_BE_env.vgaInfo.pcidev,
191 				     PCI_CLASS_DEVICE + 1, &baseclass);
192 		if (M.x86.R_CL == interface && M.x86.R_CH == subclass
193 		    && (u8) (M.x86.R_ECX >> 16) == baseclass) {
194 #else
195 		if (M.x86.R_CL == _BE_env.vgaInfo.pciInfo->Interface &&
196 		    M.x86.R_CH == _BE_env.vgaInfo.pciInfo->SubClass &&
197 		    (u8) (M.x86.R_ECX >> 16) ==
198 		    _BE_env.vgaInfo.pciInfo->BaseClass) {
199 #endif
200 			M.x86.R_AH = SUCCESSFUL;
201 			M.x86.R_BX = pciSlot;
202 		}
203 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
204 		break;
205 	case 0xB108:		/* Read configuration byte */
206 		M.x86.R_AH = BAD_REGISTER_NUMBER;
207 		if (M.x86.R_BX == pciSlot) {
208 			M.x86.R_AH = SUCCESSFUL;
209 #ifdef __KERNEL__
210 			pci_read_config_byte(_BE_env.vgaInfo.pcidev, M.x86.R_DI,
211 					     &M.x86.R_CL);
212 #else
213 			M.x86.R_CL =
214 			    (u8) PCI_accessReg(M.x86.R_DI, 0, PCI_READ_BYTE,
215 					       _BE_env.vgaInfo.pciInfo);
216 #endif
217 		}
218 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
219 		break;
220 	case 0xB109:		/* Read configuration word */
221 		M.x86.R_AH = BAD_REGISTER_NUMBER;
222 		if (M.x86.R_BX == pciSlot) {
223 			M.x86.R_AH = SUCCESSFUL;
224 #ifdef __KERNEL__
225 			pci_read_config_word(_BE_env.vgaInfo.pcidev, M.x86.R_DI,
226 					     &M.x86.R_CX);
227 #else
228 			M.x86.R_CX =
229 			    (u16) PCI_accessReg(M.x86.R_DI, 0, PCI_READ_WORD,
230 						_BE_env.vgaInfo.pciInfo);
231 #endif
232 		}
233 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
234 		break;
235 	case 0xB10A:		/* Read configuration dword */
236 		M.x86.R_AH = BAD_REGISTER_NUMBER;
237 		if (M.x86.R_BX == pciSlot) {
238 			M.x86.R_AH = SUCCESSFUL;
239 #ifdef __KERNEL__
240 			pci_read_config_dword(_BE_env.vgaInfo.pcidev,
241 					      M.x86.R_DI, &M.x86.R_ECX);
242 #else
243 			M.x86.R_ECX =
244 			    (u32) PCI_accessReg(M.x86.R_DI, 0, PCI_READ_DWORD,
245 						_BE_env.vgaInfo.pciInfo);
246 #endif
247 		}
248 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
249 		break;
250 	case 0xB10B:		/* Write configuration byte */
251 		M.x86.R_AH = BAD_REGISTER_NUMBER;
252 		if (M.x86.R_BX == pciSlot) {
253 			M.x86.R_AH = SUCCESSFUL;
254 #ifdef __KERNEL__
255 			pci_write_config_byte(_BE_env.vgaInfo.pcidev,
256 					      M.x86.R_DI, M.x86.R_CL);
257 #else
258 			PCI_accessReg(M.x86.R_DI, M.x86.R_CL, PCI_WRITE_BYTE,
259 				      _BE_env.vgaInfo.pciInfo);
260 #endif
261 		}
262 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
263 		break;
264 	case 0xB10C:		/* Write configuration word */
265 		M.x86.R_AH = BAD_REGISTER_NUMBER;
266 		if (M.x86.R_BX == pciSlot) {
267 			M.x86.R_AH = SUCCESSFUL;
268 #ifdef __KERNEL__
269 			pci_write_config_word(_BE_env.vgaInfo.pcidev,
270 					      M.x86.R_DI, M.x86.R_CX);
271 #else
272 			PCI_accessReg(M.x86.R_DI, M.x86.R_CX, PCI_WRITE_WORD,
273 				      _BE_env.vgaInfo.pciInfo);
274 #endif
275 		}
276 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
277 		break;
278 	case 0xB10D:		/* Write configuration dword */
279 		M.x86.R_AH = BAD_REGISTER_NUMBER;
280 		if (M.x86.R_BX == pciSlot) {
281 			M.x86.R_AH = SUCCESSFUL;
282 #ifdef __KERNEL__
283 			pci_write_config_dword(_BE_env.vgaInfo.pcidev,
284 					       M.x86.R_DI, M.x86.R_ECX);
285 #else
286 			PCI_accessReg(M.x86.R_DI, M.x86.R_ECX, PCI_WRITE_DWORD,
287 				      _BE_env.vgaInfo.pciInfo);
288 #endif
289 		}
290 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
291 		break;
292 	default:
293 		printf("biosEmu/bios.int1a: unknown function AX=%#04x\n",
294 		       M.x86.R_AX);
295 	}
296 }
297 
298 /****************************************************************************
299 REMARKS:
300 This function initialises the BIOS emulation functions for the specific
301 PCI display device. We insulate the real mode BIOS from any other devices
302 on the bus, so that it will work correctly thinking that it is the only
303 device present on the bus (ie: avoiding any adapters present in from of
304 the device we are trying to control).
305 ****************************************************************************/
306 #define BE_constLE_32(v)    ((((((v)&0xff00)>>8)|(((v)&0xff)<<8))<<16)|(((((v)&0xff000000)>>8)|(((v)&0x00ff0000)<<8))>>16))
307 
308 void _BE_bios_init(u32 * intrTab)
309 {
310 	int i;
311 	X86EMU_intrFuncs bios_intr_tab[256];
312 
313 	for (i = 0; i < 256; ++i) {
314 		intrTab[i] = BE_constLE_32(BIOS_SEG << 16);
315 		bios_intr_tab[i] = undefined_intr;
316 	}
317 	bios_intr_tab[0x10] = int10;
318 	bios_intr_tab[0x1A] = int1A;
319 	bios_intr_tab[0x42] = int42;
320 	bios_intr_tab[0x6D] = int10;
321 	X86EMU_setupIntrFuncs(bios_intr_tab);
322 }
323