xref: /linux/arch/x86/include/asm/setup.h (revision 69bfec7548f4c1595bac0e3ddfc0458a5af31f4c)
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 __ASSEMBLY__
31 #include <asm/bootparam.h>
32 #include <asm/x86_init.h>
33 
34 extern u64 relocated_ramdisk;
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 
50 extern void reserve_standard_io_resources(void);
51 extern void i386_reserve_resources(void);
52 extern unsigned long __startup_64(unsigned long physaddr, struct boot_params *bp);
53 extern void startup_64_setup_env(unsigned long physbase);
54 extern void early_setup_idt(void);
55 extern void __init do_early_exception(struct pt_regs *regs, int trapnr);
56 
57 #ifdef CONFIG_X86_INTEL_MID
58 extern void x86_intel_mid_early_setup(void);
59 #else
60 static inline void x86_intel_mid_early_setup(void) { }
61 #endif
62 
63 #ifdef CONFIG_X86_INTEL_CE
64 extern void x86_ce4100_early_setup(void);
65 #else
66 static inline void x86_ce4100_early_setup(void) { }
67 #endif
68 
69 #ifndef _SETUP
70 
71 #include <asm/espfix.h>
72 #include <linux/kernel.h>
73 
74 /*
75  * This is set up by the setup-routine at boot-time
76  */
77 extern struct boot_params boot_params;
78 extern char _text[];
79 
80 static inline bool kaslr_enabled(void)
81 {
82 	return IS_ENABLED(CONFIG_RANDOMIZE_MEMORY) &&
83 		!!(boot_params.hdr.loadflags & KASLR_FLAG);
84 }
85 
86 /*
87  * Apply no randomization if KASLR was disabled at boot or if KASAN
88  * is enabled. KASAN shadow mappings rely on regions being PGD aligned.
89  */
90 static inline bool kaslr_memory_enabled(void)
91 {
92 	return kaslr_enabled() && !IS_ENABLED(CONFIG_KASAN);
93 }
94 
95 static inline unsigned long kaslr_offset(void)
96 {
97 	return (unsigned long)&_text - __START_KERNEL;
98 }
99 
100 /*
101  * Do NOT EVER look at the BIOS memory size location.
102  * It does not work on many machines.
103  */
104 #define LOWMEMSIZE()	(0x9f000)
105 
106 /* exceedingly early brk-like allocator */
107 extern unsigned long _brk_end;
108 void *extend_brk(size_t size, size_t align);
109 
110 /*
111  * Reserve space in the .brk section, which is a block of memory from which the
112  * caller is allowed to allocate very early (before even memblock is available)
113  * by calling extend_brk().  All allocated memory will be eventually converted
114  * to memblock.  Any leftover unallocated memory will be freed.
115  *
116  * The size is in bytes.
117  */
118 #define RESERVE_BRK(name, size)					\
119 	__section(".bss..brk") __aligned(1) __used	\
120 	static char __brk_##name[size]
121 
122 extern void probe_roms(void);
123 
124 void clear_bss(void);
125 
126 #ifdef __i386__
127 
128 asmlinkage void __init i386_start_kernel(void);
129 
130 #else
131 asmlinkage void __init x86_64_start_kernel(char *real_mode);
132 asmlinkage void __init x86_64_start_reservations(char *real_mode_data);
133 
134 #endif /* __i386__ */
135 #endif /* _SETUP */
136 
137 #else  /* __ASSEMBLY */
138 
139 .macro __RESERVE_BRK name, size
140 	.pushsection .bss..brk, "aw"
141 SYM_DATA_START(__brk_\name)
142 	.skip \size
143 SYM_DATA_END(__brk_\name)
144 	.popsection
145 .endm
146 
147 #define RESERVE_BRK(name, size) __RESERVE_BRK name, size
148 
149 #endif /* __ASSEMBLY__ */
150 
151 #endif /* _ASM_X86_SETUP_H */
152