xref: /linux/arch/x86/include/asm/setup.h (revision 47cf96fbe393839b125a9b694a8cfdd3f4216baa)
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 startup_64_load_idt(void *vc_handler);
56 extern void early_setup_idt(void);
57 extern void __init do_early_exception(struct pt_regs *regs, int trapnr);
58 
59 #ifdef CONFIG_X86_INTEL_MID
60 extern void x86_intel_mid_early_setup(void);
61 #else
62 static inline void x86_intel_mid_early_setup(void) { }
63 #endif
64 
65 #ifdef CONFIG_X86_INTEL_CE
66 extern void x86_ce4100_early_setup(void);
67 #else
68 static inline void x86_ce4100_early_setup(void) { }
69 #endif
70 
71 #ifndef _SETUP
72 
73 #include <asm/espfix.h>
74 #include <linux/kernel.h>
75 
76 /*
77  * This is set up by the setup-routine at boot-time
78  */
79 extern struct boot_params boot_params;
80 extern char _text[];
81 
82 static inline bool kaslr_enabled(void)
83 {
84 	return IS_ENABLED(CONFIG_RANDOMIZE_MEMORY) &&
85 		!!(boot_params.hdr.loadflags & KASLR_FLAG);
86 }
87 
88 /*
89  * Apply no randomization if KASLR was disabled at boot or if KASAN
90  * is enabled. KASAN shadow mappings rely on regions being PGD aligned.
91  */
92 static inline bool kaslr_memory_enabled(void)
93 {
94 	return kaslr_enabled() && !IS_ENABLED(CONFIG_KASAN);
95 }
96 
97 static inline unsigned long kaslr_offset(void)
98 {
99 	return (unsigned long)&_text - __START_KERNEL;
100 }
101 
102 /*
103  * Do NOT EVER look at the BIOS memory size location.
104  * It does not work on many machines.
105  */
106 #define LOWMEMSIZE()	(0x9f000)
107 
108 /* exceedingly early brk-like allocator */
109 extern unsigned long _brk_end;
110 void *extend_brk(size_t size, size_t align);
111 
112 /*
113  * Reserve space in the .brk section, which is a block of memory from which the
114  * caller is allowed to allocate very early (before even memblock is available)
115  * by calling extend_brk().  All allocated memory will be eventually converted
116  * to memblock.  Any leftover unallocated memory will be freed.
117  *
118  * The size is in bytes.
119  */
120 #define RESERVE_BRK(name, size)					\
121 	__section(".bss..brk") __aligned(1) __used	\
122 	static char __brk_##name[size]
123 
124 extern void probe_roms(void);
125 
126 void clear_bss(void);
127 
128 #ifdef __i386__
129 
130 asmlinkage void __init __noreturn i386_start_kernel(void);
131 void __init mk_early_pgtbl_32(void);
132 
133 #else
134 asmlinkage void __init __noreturn x86_64_start_kernel(char *real_mode);
135 asmlinkage void __init __noreturn x86_64_start_reservations(char *real_mode_data);
136 
137 #endif /* __i386__ */
138 #endif /* _SETUP */
139 
140 #ifdef CONFIG_CMDLINE_BOOL
141 extern bool builtin_cmdline_added __ro_after_init;
142 #else
143 #define builtin_cmdline_added 0
144 #endif
145 
146 #else  /* __ASSEMBLER__ */
147 
148 .macro __RESERVE_BRK name, size
149 	.pushsection .bss..brk, "aw"
150 SYM_DATA_START(__brk_\name)
151 	.skip \size
152 SYM_DATA_END(__brk_\name)
153 	.popsection
154 .endm
155 
156 #define RESERVE_BRK(name, size) __RESERVE_BRK name, size
157 
158 #endif /* __ASSEMBLER__ */
159 
160 #endif /* _ASM_X86_SETUP_H */
161