xref: /linux/arch/x86/boot/boot.h (revision 7fc2cd2e4b398c57c9cf961cfea05eadbf34c05c)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /* -*- linux-c -*- ------------------------------------------------------- *
3  *
4  *   Copyright (C) 1991, 1992 Linus Torvalds
5  *   Copyright 2007 rPath, Inc. - All Rights Reserved
6  *   Copyright 2009 Intel Corporation; author H. Peter Anvin
7  *
8  * ----------------------------------------------------------------------- */
9 
10 /*
11  * Header file for the real-mode kernel code
12  */
13 
14 #ifndef BOOT_BOOT_H
15 #define BOOT_BOOT_H
16 
17 #define STACK_SIZE	1024	/* Minimum number of bytes for stack */
18 
19 #ifndef __ASSEMBLER__
20 
21 #include <linux/stdarg.h>
22 #include <linux/types.h>
23 #include <linux/edd.h>
24 #include <asm/setup.h>
25 #include <asm/asm.h>
26 #include "bitops.h"
27 #include "ctype.h"
28 #include "cpuflags.h"
29 #include "io.h"
30 
31 /* Useful macros */
32 #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
33 
34 extern struct setup_header hdr;
35 extern struct boot_params boot_params;
36 
37 #define cpu_relax()	asm volatile("pause")
38 
39 static inline void io_delay(void)
40 {
41 	const u16 DELAY_PORT = 0x80;
42 	outb(0, DELAY_PORT);
43 }
44 
45 /* These functions are used to reference data in other segments. */
46 
47 static inline u16 ds(void)
48 {
49 	u16 seg;
50 	asm("movw %%ds,%0" : "=rm" (seg));
51 	return seg;
52 }
53 
54 static inline void set_fs(u16 seg)
55 {
56 	asm volatile("movw %0,%%fs" : : "rm" (seg));
57 }
58 static inline u16 fs(void)
59 {
60 	u16 seg;
61 	asm volatile("movw %%fs,%0" : "=rm" (seg));
62 	return seg;
63 }
64 
65 static inline void set_gs(u16 seg)
66 {
67 	asm volatile("movw %0,%%gs" : : "rm" (seg));
68 }
69 static inline u16 gs(void)
70 {
71 	u16 seg;
72 	asm volatile("movw %%gs,%0" : "=rm" (seg));
73 	return seg;
74 }
75 
76 typedef unsigned int addr_t;
77 
78 static inline u8 rdfs8(addr_t addr)
79 {
80 	u8 *ptr = (u8 *)absolute_pointer(addr);
81 	u8 v;
82 	asm volatile("movb %%fs:%1,%0" : "=q" (v) : "m" (*ptr));
83 	return v;
84 }
85 static inline u16 rdfs16(addr_t addr)
86 {
87 	u16 *ptr = (u16 *)absolute_pointer(addr);
88 	u16 v;
89 	asm volatile("movw %%fs:%1,%0" : "=r" (v) : "m" (*ptr));
90 	return v;
91 }
92 static inline u32 rdfs32(addr_t addr)
93 {
94 	u32 *ptr = (u32 *)absolute_pointer(addr);
95 	u32 v;
96 	asm volatile("movl %%fs:%1,%0" : "=r" (v) : "m" (*ptr));
97 	return v;
98 }
99 
100 static inline void wrfs8(u8 v, addr_t addr)
101 {
102 	u8 *ptr = (u8 *)absolute_pointer(addr);
103 	asm volatile("movb %1,%%fs:%0" : "+m" (*ptr) : "qi" (v));
104 }
105 static inline void wrfs16(u16 v, addr_t addr)
106 {
107 	u16 *ptr = (u16 *)absolute_pointer(addr);
108 	asm volatile("movw %1,%%fs:%0" : "+m" (*ptr) : "ri" (v));
109 }
110 static inline void wrfs32(u32 v, addr_t addr)
111 {
112 	u32 *ptr = (u32 *)absolute_pointer(addr);
113 	asm volatile("movl %1,%%fs:%0" : "+m" (*ptr) : "ri" (v));
114 }
115 
116 static inline u8 rdgs8(addr_t addr)
117 {
118 	u8 *ptr = (u8 *)absolute_pointer(addr);
119 	u8 v;
120 	asm volatile("movb %%gs:%1,%0" : "=q" (v) : "m" (*ptr));
121 	return v;
122 }
123 static inline u16 rdgs16(addr_t addr)
124 {
125 	u16 *ptr = (u16 *)absolute_pointer(addr);
126 	u16 v;
127 	asm volatile("movw %%gs:%1,%0" : "=r" (v) : "m" (*ptr));
128 	return v;
129 }
130 static inline u32 rdgs32(addr_t addr)
131 {
132 	u32 *ptr = (u32 *)absolute_pointer(addr);
133 	u32 v;
134 	asm volatile("movl %%gs:%1,%0" : "=r" (v) : "m" (*ptr));
135 	return v;
136 }
137 
138 static inline void wrgs8(u8 v, addr_t addr)
139 {
140 	u8 *ptr = (u8 *)absolute_pointer(addr);
141 	asm volatile("movb %1,%%gs:%0" : "+m" (*ptr) : "qi" (v));
142 }
143 static inline void wrgs16(u16 v, addr_t addr)
144 {
145 	u16 *ptr = (u16 *)absolute_pointer(addr);
146 	asm volatile("movw %1,%%gs:%0" : "+m" (*ptr) : "ri" (v));
147 }
148 static inline void wrgs32(u32 v, addr_t addr)
149 {
150 	u32 *ptr = (u32 *)absolute_pointer(addr);
151 	asm volatile("movl %1,%%gs:%0" : "+m" (*ptr) : "ri" (v));
152 }
153 
154 /* Note: these only return true/false, not a signed return value! */
155 static inline bool memcmp_fs(const void *s1, addr_t s2, size_t len)
156 {
157 	bool diff;
158 	asm volatile("fs repe cmpsb"
159 		     : "=@ccnz" (diff), "+D" (s1), "+S" (s2), "+c" (len));
160 	return diff;
161 }
162 static inline bool memcmp_gs(const void *s1, addr_t s2, size_t len)
163 {
164 	bool diff;
165 	asm volatile("gs repe cmpsb"
166 		     : "=@ccnz" (diff), "+D" (s1), "+S" (s2), "+c" (len));
167 	return diff;
168 }
169 
170 /* Heap -- available for dynamic lists. */
171 extern char _end[];
172 extern char *HEAP;
173 extern char *heap_end;
174 #define RESET_HEAP() ((void *)( HEAP = _end ))
175 static inline char *__get_heap(size_t s, size_t a, size_t n)
176 {
177 	char *tmp;
178 
179 	HEAP = (char *)(((size_t)HEAP+(a-1)) & ~(a-1));
180 	tmp = HEAP;
181 	HEAP += s*n;
182 	return tmp;
183 }
184 #define GET_HEAP(type, n) \
185 	((type *)__get_heap(sizeof(type),__alignof__(type),(n)))
186 
187 static inline bool heap_free(size_t n)
188 {
189 	return (int)(heap_end-HEAP) >= (int)n;
190 }
191 
192 /* copy.S */
193 
194 void copy_to_fs(addr_t dst, void *src, size_t len);
195 void *copy_from_fs(void *dst, addr_t src, size_t len);
196 
197 /* a20.c */
198 int enable_a20(void);
199 
200 /* apm.c */
201 int query_apm_bios(void);
202 
203 /* bioscall.c */
204 struct biosregs {
205 	union {
206 		struct {
207 			u32 edi;
208 			u32 esi;
209 			u32 ebp;
210 			u32 _esp;
211 			u32 ebx;
212 			u32 edx;
213 			u32 ecx;
214 			u32 eax;
215 			u32 _fsgs;
216 			u32 _dses;
217 			u32 eflags;
218 		};
219 		struct {
220 			u16 di, hdi;
221 			u16 si, hsi;
222 			u16 bp, hbp;
223 			u16 _sp, _hsp;
224 			u16 bx, hbx;
225 			u16 dx, hdx;
226 			u16 cx, hcx;
227 			u16 ax, hax;
228 			u16 gs, fs;
229 			u16 es, ds;
230 			u16 flags, hflags;
231 		};
232 		struct {
233 			u8 dil, dih, edi2, edi3;
234 			u8 sil, sih, esi2, esi3;
235 			u8 bpl, bph, ebp2, ebp3;
236 			u8 _spl, _sph, _esp2, _esp3;
237 			u8 bl, bh, ebx2, ebx3;
238 			u8 dl, dh, edx2, edx3;
239 			u8 cl, ch, ecx2, ecx3;
240 			u8 al, ah, eax2, eax3;
241 		};
242 	};
243 };
244 void intcall(u8 int_no, const struct biosregs *ireg, struct biosregs *oreg);
245 
246 /* cmdline.c */
247 int __cmdline_find_option(unsigned long cmdline_ptr, const char *option, char *buffer, int bufsize);
248 int __cmdline_find_option_bool(unsigned long cmdline_ptr, const char *option);
249 static inline int cmdline_find_option(const char *option, char *buffer, int bufsize)
250 {
251 	unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
252 
253 	if (cmd_line_ptr >= 0x100000)
254 		return -1;      /* inaccessible */
255 
256 	return __cmdline_find_option(cmd_line_ptr, option, buffer, bufsize);
257 }
258 
259 static inline int cmdline_find_option_bool(const char *option)
260 {
261 	unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
262 
263 	if (cmd_line_ptr >= 0x100000)
264 		return -1;      /* inaccessible */
265 
266 	return __cmdline_find_option_bool(cmd_line_ptr, option);
267 }
268 
269 /* cpu.c, cpucheck.c */
270 int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr);
271 int check_knl_erratum(void);
272 int validate_cpu(void);
273 
274 /* early_serial_console.c */
275 extern int early_serial_base;
276 void console_init(void);
277 
278 /* edd.c */
279 void query_edd(void);
280 
281 /* header.S */
282 void __attribute__((noreturn)) die(void);
283 
284 /* memory.c */
285 void detect_memory(void);
286 
287 /* pm.c */
288 void __attribute__((noreturn)) go_to_protected_mode(void);
289 
290 /* pmjump.S */
291 void __attribute__((noreturn))
292 	protected_mode_jump(u32 entrypoint, u32 bootparams);
293 
294 /* printf.c */
295 int sprintf(char *buf, const char *fmt, ...);
296 int vsprintf(char *buf, const char *fmt, va_list args);
297 int printf(const char *fmt, ...);
298 
299 /* regs.c */
300 void initregs(struct biosregs *regs);
301 
302 /* string.c */
303 int strcmp(const char *str1, const char *str2);
304 int strncmp(const char *cs, const char *ct, size_t count);
305 size_t strnlen(const char *s, size_t maxlen);
306 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base);
307 size_t strlen(const char *s);
308 char *strchr(const char *s, int c);
309 
310 /* tty.c */
311 void puts(const char *);
312 void putchar(int);
313 int getchar(void);
314 void kbd_flush(void);
315 int getchar_timeout(void);
316 
317 /* video.c */
318 void set_video(void);
319 
320 /* video-mode.c */
321 int set_mode(u16 mode);
322 int mode_defined(u16 mode);
323 void probe_cards(int unsafe);
324 
325 /* video-vesa.c */
326 void vesa_store_edid(void);
327 
328 #endif /* __ASSEMBLER__ */
329 
330 #endif /* BOOT_BOOT_H */
331