xref: /linux/arch/x86/include/asm/setup.h (revision acc53a0b4c156877773da6e9eea4113dc7e770ae)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_SETUP_H
3 #define _ASM_X86_SETUP_H
4 
5 #include <uapi/asm/setup.h>
6 
7 #define COMMAND_LINE_SIZE 2048
8 
9 #include <linux/linkage.h>
10 #include <asm/page_types.h>
11 #include <asm/ibt.h>
12 
13 #ifdef __i386__
14 
15 #include <linux/pfn.h>
16 /*
17  * Reserved space for vmalloc and iomap - defined in asm/page.h
18  */
19 #define MAXMEM_PFN	PFN_DOWN(MAXMEM)
20 #define MAX_NONPAE_PFN	(1 << 20)
21 
22 #endif /* __i386__ */
23 
24 #define PARAM_SIZE 4096		/* sizeof(struct boot_params) */
25 
26 #define OLD_CL_MAGIC		0xA33F
27 #define OLD_CL_ADDRESS		0x020	/* Relative to real mode data */
28 #define NEW_CL_POINTER		0x228	/* Relative to real mode data */
29 
30 #ifndef __ASSEMBLER__
31 #include <linux/cache.h>
32 
33 #include <asm/bootparam.h>
34 #include <asm/x86_init.h>
35 
36 /* Interrupt control for vSMPowered x86_64 systems */
37 #ifdef CONFIG_X86_64
38 void vsmp_init(void);
39 #else
40 static inline void vsmp_init(void) { }
41 #endif
42 
43 struct pt_regs;
44 
45 void setup_bios_corruption_check(void);
46 void early_platform_quirks(void);
47 
48 extern unsigned long saved_video_mode;
49 extern unsigned long acpi_realmode_flags;
50 
51 extern void reserve_standard_io_resources(void);
52 extern void i386_reserve_resources(void);
53 extern unsigned long __startup_64(unsigned long p2v_offset, struct boot_params *bp);
54 extern void startup_64_setup_gdt_idt(void);
55 extern void early_setup_idt(void);
56 extern void __init do_early_exception(struct pt_regs *regs, int trapnr);
57 
58 #ifdef CONFIG_X86_INTEL_MID
59 extern void x86_intel_mid_early_setup(void);
60 #else
61 static inline void x86_intel_mid_early_setup(void) { }
62 #endif
63 
64 #ifdef CONFIG_X86_INTEL_CE
65 extern void x86_ce4100_early_setup(void);
66 #else
67 static inline void x86_ce4100_early_setup(void) { }
68 #endif
69 
70 #include <linux/kexec_handover.h>
71 
72 #ifndef _SETUP
73 
74 #include <asm/espfix.h>
75 #include <linux/kernel.h>
76 
77 /*
78  * This is set up by the setup-routine at boot-time
79  */
80 extern struct boot_params boot_params;
81 extern char _text[];
82 
83 static inline bool kaslr_enabled(void)
84 {
85 	return IS_ENABLED(CONFIG_RANDOMIZE_MEMORY) &&
86 		!!(boot_params.hdr.loadflags & KASLR_FLAG);
87 }
88 
89 /*
90  * Apply no randomization if KASLR was disabled at boot or if KASAN
91  * is enabled. KASAN shadow mappings rely on regions being PGD aligned.
92  */
93 static inline bool kaslr_memory_enabled(void)
94 {
95 	return kaslr_enabled() && !IS_ENABLED(CONFIG_KASAN);
96 }
97 
98 static inline unsigned long kaslr_offset(void)
99 {
100 	return (unsigned long)&_text - __START_KERNEL;
101 }
102 
103 /*
104  * Do NOT EVER look at the BIOS memory size location.
105  * It does not work on many machines.
106  */
107 #define LOWMEMSIZE()	(0x9f000)
108 
109 /* exceedingly early brk-like allocator */
110 extern unsigned long _brk_end;
111 void *extend_brk(size_t size, size_t align);
112 
113 /*
114  * Reserve space in the .brk section, which is a block of memory from which the
115  * caller is allowed to allocate very early (before even memblock is available)
116  * by calling extend_brk().  All allocated memory will be eventually converted
117  * to memblock.  Any leftover unallocated memory will be freed.
118  *
119  * The size is in bytes.
120  */
121 #define RESERVE_BRK(name, size)					\
122 	__section(".bss..brk") __aligned(1) __used	\
123 	static char __brk_##name[size]
124 
125 extern void probe_roms(void);
126 
127 void clear_bss(void);
128 
129 #ifdef __i386__
130 
131 asmlinkage void __init __noreturn i386_start_kernel(void);
132 void __init mk_early_pgtbl_32(void);
133 
134 #else
135 asmlinkage void __init __noreturn x86_64_start_kernel(char *real_mode);
136 asmlinkage void __init __noreturn x86_64_start_reservations(char *real_mode_data);
137 
138 #endif /* __i386__ */
139 #endif /* _SETUP */
140 
141 #ifdef CONFIG_CMDLINE_BOOL
142 extern bool builtin_cmdline_added __ro_after_init;
143 #else
144 #define builtin_cmdline_added 0
145 #endif
146 
147 #else  /* __ASSEMBLER__ */
148 
149 .macro __RESERVE_BRK name, size
150 	.pushsection .bss..brk, "aw"
151 SYM_DATA_START(__brk_\name)
152 	.skip \size
153 SYM_DATA_END(__brk_\name)
154 	.popsection
155 .endm
156 
157 #define RESERVE_BRK(name, size) __RESERVE_BRK name, size
158 
159 #endif /* __ASSEMBLER__ */
160 
161 #endif /* _ASM_X86_SETUP_H */
162