xref: /linux/arch/x86/include/asm/realmode.h (revision 44f57d78)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ARCH_X86_REALMODE_H
3 #define _ARCH_X86_REALMODE_H
4 
5 /*
6  * Flag bit definitions for use with the flags field of the trampoline header
7  * in the CONFIG_X86_64 variant.
8  */
9 #define TH_FLAGS_SME_ACTIVE_BIT		0
10 #define TH_FLAGS_SME_ACTIVE		BIT(TH_FLAGS_SME_ACTIVE_BIT)
11 
12 #ifndef __ASSEMBLY__
13 
14 #include <linux/types.h>
15 #include <asm/io.h>
16 
17 /* This must match data at realmode.S */
18 struct real_mode_header {
19 	u32	text_start;
20 	u32	ro_end;
21 	/* SMP trampoline */
22 	u32	trampoline_start;
23 	u32	trampoline_status;
24 	u32	trampoline_header;
25 #ifdef CONFIG_X86_64
26 	u32	trampoline_pgd;
27 #endif
28 	/* ACPI S3 wakeup */
29 #ifdef CONFIG_ACPI_SLEEP
30 	u32	wakeup_start;
31 	u32	wakeup_header;
32 #endif
33 	/* APM/BIOS reboot */
34 	u32	machine_real_restart_asm;
35 #ifdef CONFIG_X86_64
36 	u32	machine_real_restart_seg;
37 #endif
38 };
39 
40 /* This must match data at trampoline_32/64.S */
41 struct trampoline_header {
42 #ifdef CONFIG_X86_32
43 	u32 start;
44 	u16 gdt_pad;
45 	u16 gdt_limit;
46 	u32 gdt_base;
47 #else
48 	u64 start;
49 	u64 efer;
50 	u32 cr4;
51 	u32 flags;
52 #endif
53 };
54 
55 extern struct real_mode_header *real_mode_header;
56 extern unsigned char real_mode_blob_end[];
57 
58 extern unsigned long initial_code;
59 extern unsigned long initial_gs;
60 extern unsigned long initial_stack;
61 
62 extern unsigned char real_mode_blob[];
63 extern unsigned char real_mode_relocs[];
64 
65 #ifdef CONFIG_X86_32
66 extern unsigned char startup_32_smp[];
67 extern unsigned char boot_gdt[];
68 #else
69 extern unsigned char secondary_startup_64[];
70 #endif
71 
72 static inline size_t real_mode_size_needed(void)
73 {
74 	if (real_mode_header)
75 		return 0;	/* already allocated. */
76 
77 	return ALIGN(real_mode_blob_end - real_mode_blob, PAGE_SIZE);
78 }
79 
80 static inline void set_real_mode_mem(phys_addr_t mem)
81 {
82 	real_mode_header = (struct real_mode_header *) __va(mem);
83 }
84 
85 void reserve_real_mode(void);
86 
87 #endif /* __ASSEMBLY__ */
88 
89 #endif /* _ARCH_X86_REALMODE_H */
90