xref: /openbmc/u-boot/arch/x86/lib/bios.h (revision 274bced8)
1 /*
2  * From Coreboot file device/oprom/realmode/x86.h
3  *
4  * Copyright (C) 2007 Advanced Micro Devices, Inc.
5  * Copyright (C) 2009-2010 coresystems GmbH
6  *
7  * SPDX-License-Identifier:	GPL-2.0
8  */
9 
10 #ifndef _X86_LIB_BIOS_H
11 #define _X86_LIB_BIOS_H
12 
13 #include <linux/linkage.h>
14 
15 #define REALMODE_BASE		0x600
16 
17 #ifdef __ASSEMBLY__
18 
19 #define PTR_TO_REAL_MODE(x)	(x - asm_realmode_code + REALMODE_BASE)
20 
21 #else
22 
23 /* Convert a symbol address to our real mode area */
24 #define PTR_TO_REAL_MODE(sym)\
25 	(void *)(REALMODE_BASE + ((char *)&(sym) - (char *)&asm_realmode_code))
26 
27 /*
28  * The following symbols cannot be used directly. They need to be fixed up
29  * to point to the correct address location after the code has been copied
30  * to REALMODE_BASE. Absolute symbols are not used because those symbols are
31  * relocated by U-Boot.
32  */
33 extern unsigned char asm_realmode_call, __realmode_interrupt;
34 extern unsigned char asm_realmode_buffer;
35 
36 #define DOWNTO8(A) \
37 	union { \
38 		struct { \
39 			union { \
40 				struct { \
41 					uint8_t A##l; \
42 					uint8_t A##h; \
43 				} __packed; \
44 				uint16_t A##x; \
45 			} __packed; \
46 			uint16_t h##A##x; \
47 		} __packed; \
48 		uint32_t e##A##x; \
49 	} __packed;
50 
51 #define DOWNTO16(A) \
52 	union { \
53 		struct { \
54 			uint16_t A; \
55 			uint16_t h##A; \
56 		} __packed; \
57 		uint32_t e##A; \
58 	} __packed;
59 
60 struct eregs {
61 	DOWNTO8(a);
62 	DOWNTO8(c);
63 	DOWNTO8(d);
64 	DOWNTO8(b);
65 	DOWNTO16(sp);
66 	DOWNTO16(bp);
67 	DOWNTO16(si);
68 	DOWNTO16(di);
69 	uint32_t vector;
70 	uint32_t error_code;
71 	uint32_t eip;
72 	uint32_t cs;
73 	uint32_t eflags;
74 };
75 
76 struct realmode_idt {
77 	u16 offset, cs;
78 };
79 
80 void x86_exception(struct eregs *info);
81 
82 /* From x86_asm.S */
83 extern unsigned char __idt_handler;
84 extern unsigned int __idt_handler_size;
85 extern unsigned char asm_realmode_code;
86 extern unsigned int asm_realmode_code_size;
87 
88 asmlinkage void (*realmode_call)(u32 addr, u32 eax, u32 ebx, u32 ecx, u32 edx,
89 				 u32 esi, u32 edi);
90 
91 asmlinkage void (*realmode_interrupt)(u32 intno, u32 eax, u32 ebx, u32 ecx,
92 				      u32 edx, u32 esi, u32 edi);
93 
94 int int10_handler(void);
95 int int12_handler(void);
96 int int16_handler(void);
97 int int1a_handler(void);
98 #endif /*__ASSEMBLY__ */
99 
100 #endif
101