1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * From Coreboot file device/oprom/realmode/x86.h
4  *
5  * Copyright (C) 2007 Advanced Micro Devices, Inc.
6  * Copyright (C) 2009-2010 coresystems GmbH
7  */
8 
9 #ifndef _X86_LIB_BIOS_H
10 #define _X86_LIB_BIOS_H
11 
12 #include <linux/linkage.h>
13 
14 #define REALMODE_BASE		0x600
15 
16 #ifdef __ASSEMBLY__
17 
18 #define PTR_TO_REAL_MODE(x)	(x - asm_realmode_code + REALMODE_BASE)
19 
20 #else
21 
22 /* Convert a symbol address to our real mode area */
23 #define PTR_TO_REAL_MODE(sym)\
24 	(void *)(REALMODE_BASE + ((char *)&(sym) - (char *)&asm_realmode_code))
25 
26 /*
27  * The following symbols cannot be used directly. They need to be fixed up
28  * to point to the correct address location after the code has been copied
29  * to REALMODE_BASE. Absolute symbols are not used because those symbols are
30  * relocated by U-Boot.
31  */
32 extern unsigned char asm_realmode_call, __realmode_interrupt;
33 extern unsigned char asm_realmode_buffer;
34 
35 #define DOWNTO8(A) \
36 	union { \
37 		struct { \
38 			union { \
39 				struct { \
40 					uint8_t A##l; \
41 					uint8_t A##h; \
42 				} __packed; \
43 				uint16_t A##x; \
44 			} __packed; \
45 			uint16_t h##A##x; \
46 		} __packed; \
47 		uint32_t e##A##x; \
48 	} __packed;
49 
50 #define DOWNTO16(A) \
51 	union { \
52 		struct { \
53 			uint16_t A; \
54 			uint16_t h##A; \
55 		} __packed; \
56 		uint32_t e##A; \
57 	} __packed;
58 
59 struct eregs {
60 	DOWNTO8(a);
61 	DOWNTO8(c);
62 	DOWNTO8(d);
63 	DOWNTO8(b);
64 	DOWNTO16(sp);
65 	DOWNTO16(bp);
66 	DOWNTO16(si);
67 	DOWNTO16(di);
68 	uint32_t vector;
69 	uint32_t error_code;
70 	uint32_t eip;
71 	uint32_t cs;
72 	uint32_t eflags;
73 };
74 
75 struct realmode_idt {
76 	u16 offset, cs;
77 };
78 
79 void x86_exception(struct eregs *info);
80 
81 /* From x86_asm.S */
82 extern unsigned char __idt_handler;
83 extern unsigned int __idt_handler_size;
84 extern unsigned char asm_realmode_code;
85 extern unsigned int asm_realmode_code_size;
86 
87 asmlinkage void (*realmode_call)(u32 addr, u32 eax, u32 ebx, u32 ecx, u32 edx,
88 				 u32 esi, u32 edi);
89 
90 asmlinkage void (*realmode_interrupt)(u32 intno, u32 eax, u32 ebx, u32 ecx,
91 				      u32 edx, u32 esi, u32 edi);
92 
93 int int10_handler(void);
94 int int12_handler(void);
95 int int16_handler(void);
96 int int1a_handler(void);
97 #endif /*__ASSEMBLY__ */
98 
99 #endif
100