xref: /openbmc/linux/arch/x86/include/asm/setup.h (revision 99a15348)
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 unsigned long __startup_secondary_64(void);
54 extern void startup_64_setup_env(unsigned long physbase);
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 #ifndef _SETUP
71 
72 #include <asm/espfix.h>
73 #include <linux/kernel.h>
74 
75 /*
76  * This is set up by the setup-routine at boot-time
77  */
78 extern struct boot_params boot_params;
79 extern char _text[];
80 
81 static inline bool kaslr_enabled(void)
82 {
83 	return IS_ENABLED(CONFIG_RANDOMIZE_MEMORY) &&
84 		!!(boot_params.hdr.loadflags & KASLR_FLAG);
85 }
86 
87 /*
88  * Apply no randomization if KASLR was disabled at boot or if KASAN
89  * is enabled. KASAN shadow mappings rely on regions being PGD aligned.
90  */
91 static inline bool kaslr_memory_enabled(void)
92 {
93 	return kaslr_enabled() && !IS_ENABLED(CONFIG_KASAN);
94 }
95 
96 static inline unsigned long kaslr_offset(void)
97 {
98 	return (unsigned long)&_text - __START_KERNEL;
99 }
100 
101 /*
102  * Do NOT EVER look at the BIOS memory size location.
103  * It does not work on many machines.
104  */
105 #define LOWMEMSIZE()	(0x9f000)
106 
107 /* exceedingly early brk-like allocator */
108 extern unsigned long _brk_end;
109 void *extend_brk(size_t size, size_t align);
110 
111 /*
112  * Reserve space in the brk section.  The name must be unique within
113  * the file, and somewhat descriptive.  The size is in bytes.  Must be
114  * used at file scope.
115  *
116  * (This uses a temp function to wrap the asm so we can pass it the
117  * size parameter; otherwise we wouldn't be able to.  We can't use a
118  * "section" attribute on a normal variable because it always ends up
119  * being @progbits, which ends up allocating space in the vmlinux
120  * executable.)
121  */
122 #define RESERVE_BRK(name,sz)						\
123 	static void __section(".discard.text") __noendbr __used notrace	\
124 	__brk_reservation_fn_##name##__(void) {				\
125 		asm volatile (						\
126 			".pushsection .brk_reservation,\"aw\",@nobits;" \
127 			".brk." #name ":"				\
128 			" 1:.skip %c0;"					\
129 			" .size .brk." #name ", . - 1b;"		\
130 			" .popsection"					\
131 			: : "i" (sz));					\
132 	}
133 
134 extern void probe_roms(void);
135 #ifdef __i386__
136 
137 asmlinkage void __init i386_start_kernel(void);
138 
139 #else
140 asmlinkage void __init x86_64_start_kernel(char *real_mode);
141 asmlinkage void __init x86_64_start_reservations(char *real_mode_data);
142 
143 #endif /* __i386__ */
144 #endif /* _SETUP */
145 #else
146 #define RESERVE_BRK(name,sz)				\
147 	.pushsection .brk_reservation,"aw",@nobits;	\
148 .brk.name:						\
149 1:	.skip sz;					\
150 	.size .brk.name,.-1b;				\
151 	.popsection
152 #endif /* __ASSEMBLY__ */
153 #endif /* _ASM_X86_SETUP_H */
154