xref: /openbmc/u-boot/drivers/bios_emulator/bios.c (revision 93322749)
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 #define __io
45 #include <common.h>
46 #include <asm/io.h>
47 #include "biosemui.h"
48 
49 /*----------------------------- Implementation ----------------------------*/
50 
51 /****************************************************************************
52 PARAMETERS:
53 intno   - Interrupt number being serviced
54 
55 REMARKS:
56 Handler for undefined interrupts.
57 ****************************************************************************/
58 static void X86API undefined_intr(int intno)
59 {
60 	if (BE_rdw(intno * 4 + 2) == BIOS_SEG) {
61 		DB(printf("biosEmu: undefined interrupt %xh called!\n", intno);)
62 	} else
63 		X86EMU_prepareForInt(intno);
64 }
65 
66 /****************************************************************************
67 PARAMETERS:
68 intno   - Interrupt number being serviced
69 
70 REMARKS:
71 This function handles the default system BIOS Int 10h (the default is stored
72 in the Int 42h vector by the system BIOS at bootup). We only need to handle
73 a small number of special functions used by the BIOS during POST time.
74 ****************************************************************************/
75 static void X86API int42(int intno)
76 {
77 	if (M.x86.R_AH == 0x12 && M.x86.R_BL == 0x32) {
78 		if (M.x86.R_AL == 0) {
79 			/* Enable CPU accesses to video memory */
80 			PM_outpb(0x3c2, PM_inpb(0x3cc) | (u8) 0x02);
81 			return;
82 		} else if (M.x86.R_AL == 1) {
83 			/* Disable CPU accesses to video memory */
84 			PM_outpb(0x3c2, PM_inpb(0x3cc) & (u8) ~ 0x02);
85 			return;
86 		}
87 #ifdef CONFIG_X86EMU_DEBUG
88 		else {
89 			printf("int42: unknown function AH=0x12, BL=0x32, AL=%#02x\n",
90 			     M.x86.R_AL);
91 		}
92 #endif
93 	}
94 #ifdef CONFIG_X86EMU_DEBUG
95 	else {
96 		printf("int42: unknown function AH=%#02x, AL=%#02x, BL=%#02x\n",
97 		     M.x86.R_AH, M.x86.R_AL, M.x86.R_BL);
98 	}
99 #endif
100 }
101 
102 /****************************************************************************
103 PARAMETERS:
104 intno   - Interrupt number being serviced
105 
106 REMARKS:
107 This function handles the default system BIOS Int 10h. If the POST code
108 has not yet re-vectored the Int 10h BIOS interrupt vector, we handle this
109 by simply calling the int42 interrupt handler above. Very early in the
110 BIOS POST process, the vector gets replaced and we simply let the real
111 mode interrupt handler process the interrupt.
112 ****************************************************************************/
113 static void X86API int10(int intno)
114 {
115 	if (BE_rdw(intno * 4 + 2) == BIOS_SEG)
116 		int42(intno);
117 	else
118 		X86EMU_prepareForInt(intno);
119 }
120 
121 /* Result codes returned by the PCI BIOS */
122 
123 #define SUCCESSFUL          0x00
124 #define FUNC_NOT_SUPPORT    0x81
125 #define BAD_VENDOR_ID       0x83
126 #define DEVICE_NOT_FOUND    0x86
127 #define BAD_REGISTER_NUMBER 0x87
128 #define SET_FAILED          0x88
129 #define BUFFER_TOO_SMALL    0x89
130 
131 /****************************************************************************
132 PARAMETERS:
133 intno   - Interrupt number being serviced
134 
135 REMARKS:
136 This function handles the default Int 1Ah interrupt handler for the real
137 mode code, which provides support for the PCI BIOS functions. Since we only
138 want to allow the real mode BIOS code *only* see the PCI config space for
139 its own device, we only return information for the specific PCI config
140 space that we have passed in to the init function. This solves problems
141 when using the BIOS to warm boot a secondary adapter when there is an
142 identical adapter before it on the bus (some BIOS'es get confused in this
143 case).
144 ****************************************************************************/
145 static void X86API int1A(int unused)
146 {
147 	u16 pciSlot;
148 
149 #ifdef __KERNEL__
150 	u8 interface, subclass, baseclass;
151 
152 	/* Initialise the PCI slot number */
153 	pciSlot = ((int)_BE_env.vgaInfo.bus << 8) |
154 	    ((int)_BE_env.vgaInfo.device << 3) | (int)_BE_env.vgaInfo.function;
155 #else
156 /* Fail if no PCI device information has been registered */
157 	if (!_BE_env.vgaInfo.pciInfo)
158 		return;
159 
160 	pciSlot = (u16) (_BE_env.vgaInfo.pciInfo->slot.i >> 8);
161 #endif
162 	switch (M.x86.R_AX) {
163 	case 0xB101:		/* PCI bios present? */
164 		M.x86.R_AL = 0x00;	/* no config space/special cycle generation support */
165 		M.x86.R_EDX = 0x20494350;	/* " ICP" */
166 		M.x86.R_BX = 0x0210;	/* Version 2.10 */
167 		M.x86.R_CL = 0;	/* Max bus number in system */
168 		CLEAR_FLAG(F_CF);
169 		break;
170 	case 0xB102:		/* Find PCI device */
171 		M.x86.R_AH = DEVICE_NOT_FOUND;
172 #ifdef __KERNEL__
173 		if (M.x86.R_DX == _BE_env.vgaInfo.VendorID &&
174 		    M.x86.R_CX == _BE_env.vgaInfo.DeviceID && M.x86.R_SI == 0) {
175 #else
176 		if (M.x86.R_DX == _BE_env.vgaInfo.pciInfo->VendorID &&
177 		    M.x86.R_CX == _BE_env.vgaInfo.pciInfo->DeviceID &&
178 		    M.x86.R_SI == 0) {
179 #endif
180 			M.x86.R_AH = SUCCESSFUL;
181 			M.x86.R_BX = pciSlot;
182 		}
183 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
184 		break;
185 	case 0xB103:		/* Find PCI class code */
186 		M.x86.R_AH = DEVICE_NOT_FOUND;
187 #ifdef __KERNEL__
188 		pci_read_config_byte(_BE_env.vgaInfo.pcidev, PCI_CLASS_PROG,
189 				     &interface);
190 		pci_read_config_byte(_BE_env.vgaInfo.pcidev, PCI_CLASS_DEVICE,
191 				     &subclass);
192 		pci_read_config_byte(_BE_env.vgaInfo.pcidev,
193 				     PCI_CLASS_DEVICE + 1, &baseclass);
194 		if (M.x86.R_CL == interface && M.x86.R_CH == subclass
195 		    && (u8) (M.x86.R_ECX >> 16) == baseclass) {
196 #else
197 		if (M.x86.R_CL == _BE_env.vgaInfo.pciInfo->Interface &&
198 		    M.x86.R_CH == _BE_env.vgaInfo.pciInfo->SubClass &&
199 		    (u8) (M.x86.R_ECX >> 16) ==
200 		    _BE_env.vgaInfo.pciInfo->BaseClass) {
201 #endif
202 			M.x86.R_AH = SUCCESSFUL;
203 			M.x86.R_BX = pciSlot;
204 		}
205 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
206 		break;
207 	case 0xB108:		/* Read configuration byte */
208 		M.x86.R_AH = BAD_REGISTER_NUMBER;
209 		if (M.x86.R_BX == pciSlot) {
210 			M.x86.R_AH = SUCCESSFUL;
211 #ifdef __KERNEL__
212 			pci_read_config_byte(_BE_env.vgaInfo.pcidev, M.x86.R_DI,
213 					     &M.x86.R_CL);
214 #else
215 			M.x86.R_CL =
216 			    (u8) PCI_accessReg(M.x86.R_DI, 0, PCI_READ_BYTE,
217 					       _BE_env.vgaInfo.pciInfo);
218 #endif
219 		}
220 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
221 		break;
222 	case 0xB109:		/* Read configuration word */
223 		M.x86.R_AH = BAD_REGISTER_NUMBER;
224 		if (M.x86.R_BX == pciSlot) {
225 			M.x86.R_AH = SUCCESSFUL;
226 #ifdef __KERNEL__
227 			pci_read_config_word(_BE_env.vgaInfo.pcidev, M.x86.R_DI,
228 					     &M.x86.R_CX);
229 #else
230 			M.x86.R_CX =
231 			    (u16) PCI_accessReg(M.x86.R_DI, 0, PCI_READ_WORD,
232 						_BE_env.vgaInfo.pciInfo);
233 #endif
234 		}
235 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
236 		break;
237 	case 0xB10A:		/* Read configuration dword */
238 		M.x86.R_AH = BAD_REGISTER_NUMBER;
239 		if (M.x86.R_BX == pciSlot) {
240 			M.x86.R_AH = SUCCESSFUL;
241 #ifdef __KERNEL__
242 			pci_read_config_dword(_BE_env.vgaInfo.pcidev,
243 					      M.x86.R_DI, &M.x86.R_ECX);
244 #else
245 			M.x86.R_ECX =
246 			    (u32) PCI_accessReg(M.x86.R_DI, 0, PCI_READ_DWORD,
247 						_BE_env.vgaInfo.pciInfo);
248 #endif
249 		}
250 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
251 		break;
252 	case 0xB10B:		/* Write configuration byte */
253 		M.x86.R_AH = BAD_REGISTER_NUMBER;
254 		if (M.x86.R_BX == pciSlot) {
255 			M.x86.R_AH = SUCCESSFUL;
256 #ifdef __KERNEL__
257 			pci_write_config_byte(_BE_env.vgaInfo.pcidev,
258 					      M.x86.R_DI, M.x86.R_CL);
259 #else
260 			PCI_accessReg(M.x86.R_DI, M.x86.R_CL, PCI_WRITE_BYTE,
261 				      _BE_env.vgaInfo.pciInfo);
262 #endif
263 		}
264 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
265 		break;
266 	case 0xB10C:		/* Write configuration word */
267 		M.x86.R_AH = BAD_REGISTER_NUMBER;
268 		if (M.x86.R_BX == pciSlot) {
269 			M.x86.R_AH = SUCCESSFUL;
270 #ifdef __KERNEL__
271 			pci_write_config_word(_BE_env.vgaInfo.pcidev,
272 					      M.x86.R_DI, M.x86.R_CX);
273 #else
274 			PCI_accessReg(M.x86.R_DI, M.x86.R_CX, PCI_WRITE_WORD,
275 				      _BE_env.vgaInfo.pciInfo);
276 #endif
277 		}
278 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
279 		break;
280 	case 0xB10D:		/* Write configuration dword */
281 		M.x86.R_AH = BAD_REGISTER_NUMBER;
282 		if (M.x86.R_BX == pciSlot) {
283 			M.x86.R_AH = SUCCESSFUL;
284 #ifdef __KERNEL__
285 			pci_write_config_dword(_BE_env.vgaInfo.pcidev,
286 					       M.x86.R_DI, M.x86.R_ECX);
287 #else
288 			PCI_accessReg(M.x86.R_DI, M.x86.R_ECX, PCI_WRITE_DWORD,
289 				      _BE_env.vgaInfo.pciInfo);
290 #endif
291 		}
292 		CONDITIONAL_SET_FLAG((M.x86.R_AH != SUCCESSFUL), F_CF);
293 		break;
294 	default:
295 		printf("biosEmu/bios.int1a: unknown function AX=%#04x\n",
296 		       M.x86.R_AX);
297 	}
298 }
299 
300 /****************************************************************************
301 REMARKS:
302 This function initialises the BIOS emulation functions for the specific
303 PCI display device. We insulate the real mode BIOS from any other devices
304 on the bus, so that it will work correctly thinking that it is the only
305 device present on the bus (ie: avoiding any adapters present in from of
306 the device we are trying to control).
307 ****************************************************************************/
308 #define BE_constLE_32(v)    ((((((v)&0xff00)>>8)|(((v)&0xff)<<8))<<16)|(((((v)&0xff000000)>>8)|(((v)&0x00ff0000)<<8))>>16))
309 
310 void _BE_bios_init(u32 * intrTab)
311 {
312 	int i;
313 	X86EMU_intrFuncs bios_intr_tab[256];
314 
315 	for (i = 0; i < 256; ++i) {
316 		intrTab[i] = BE_constLE_32(BIOS_SEG << 16);
317 		bios_intr_tab[i] = undefined_intr;
318 	}
319 	bios_intr_tab[0x10] = int10;
320 	bios_intr_tab[0x1A] = int1A;
321 	bios_intr_tab[0x42] = int42;
322 	bios_intr_tab[0x6D] = int10;
323 	X86EMU_setupIntrFuncs(bios_intr_tab);
324 }
325