xref: /linux/arch/x86/boot/boot.h (revision 97733180fafbeb7cc3fd1c8be60d05980615f5d6)
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 __ASSEMBLY__
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 
30 /* Useful macros */
31 #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
32 
33 extern struct setup_header hdr;
34 extern struct boot_params boot_params;
35 
36 #define cpu_relax()	asm volatile("rep; nop")
37 
38 /* Basic port I/O */
39 static inline void outb(u8 v, u16 port)
40 {
41 	asm volatile("outb %0,%1" : : "a" (v), "dN" (port));
42 }
43 static inline u8 inb(u16 port)
44 {
45 	u8 v;
46 	asm volatile("inb %1,%0" : "=a" (v) : "dN" (port));
47 	return v;
48 }
49 
50 static inline void outw(u16 v, u16 port)
51 {
52 	asm volatile("outw %0,%1" : : "a" (v), "dN" (port));
53 }
54 static inline u16 inw(u16 port)
55 {
56 	u16 v;
57 	asm volatile("inw %1,%0" : "=a" (v) : "dN" (port));
58 	return v;
59 }
60 
61 static inline void outl(u32 v, u16 port)
62 {
63 	asm volatile("outl %0,%1" : : "a" (v), "dN" (port));
64 }
65 static inline u32 inl(u16 port)
66 {
67 	u32 v;
68 	asm volatile("inl %1,%0" : "=a" (v) : "dN" (port));
69 	return v;
70 }
71 
72 static inline void io_delay(void)
73 {
74 	const u16 DELAY_PORT = 0x80;
75 	asm volatile("outb %%al,%0" : : "dN" (DELAY_PORT));
76 }
77 
78 /* These functions are used to reference data in other segments. */
79 
80 static inline u16 ds(void)
81 {
82 	u16 seg;
83 	asm("movw %%ds,%0" : "=rm" (seg));
84 	return seg;
85 }
86 
87 static inline void set_fs(u16 seg)
88 {
89 	asm volatile("movw %0,%%fs" : : "rm" (seg));
90 }
91 static inline u16 fs(void)
92 {
93 	u16 seg;
94 	asm volatile("movw %%fs,%0" : "=rm" (seg));
95 	return seg;
96 }
97 
98 static inline void set_gs(u16 seg)
99 {
100 	asm volatile("movw %0,%%gs" : : "rm" (seg));
101 }
102 static inline u16 gs(void)
103 {
104 	u16 seg;
105 	asm volatile("movw %%gs,%0" : "=rm" (seg));
106 	return seg;
107 }
108 
109 typedef unsigned int addr_t;
110 
111 static inline u8 rdfs8(addr_t addr)
112 {
113 	u8 v;
114 	asm volatile("movb %%fs:%1,%0" : "=q" (v) : "m" (*(u8 *)addr));
115 	return v;
116 }
117 static inline u16 rdfs16(addr_t addr)
118 {
119 	u16 v;
120 	asm volatile("movw %%fs:%1,%0" : "=r" (v) : "m" (*(u16 *)addr));
121 	return v;
122 }
123 static inline u32 rdfs32(addr_t addr)
124 {
125 	u32 v;
126 	asm volatile("movl %%fs:%1,%0" : "=r" (v) : "m" (*(u32 *)addr));
127 	return v;
128 }
129 
130 static inline void wrfs8(u8 v, addr_t addr)
131 {
132 	asm volatile("movb %1,%%fs:%0" : "+m" (*(u8 *)addr) : "qi" (v));
133 }
134 static inline void wrfs16(u16 v, addr_t addr)
135 {
136 	asm volatile("movw %1,%%fs:%0" : "+m" (*(u16 *)addr) : "ri" (v));
137 }
138 static inline void wrfs32(u32 v, addr_t addr)
139 {
140 	asm volatile("movl %1,%%fs:%0" : "+m" (*(u32 *)addr) : "ri" (v));
141 }
142 
143 static inline u8 rdgs8(addr_t addr)
144 {
145 	u8 v;
146 	asm volatile("movb %%gs:%1,%0" : "=q" (v) : "m" (*(u8 *)addr));
147 	return v;
148 }
149 static inline u16 rdgs16(addr_t addr)
150 {
151 	u16 v;
152 	asm volatile("movw %%gs:%1,%0" : "=r" (v) : "m" (*(u16 *)addr));
153 	return v;
154 }
155 static inline u32 rdgs32(addr_t addr)
156 {
157 	u32 v;
158 	asm volatile("movl %%gs:%1,%0" : "=r" (v) : "m" (*(u32 *)addr));
159 	return v;
160 }
161 
162 static inline void wrgs8(u8 v, addr_t addr)
163 {
164 	asm volatile("movb %1,%%gs:%0" : "+m" (*(u8 *)addr) : "qi" (v));
165 }
166 static inline void wrgs16(u16 v, addr_t addr)
167 {
168 	asm volatile("movw %1,%%gs:%0" : "+m" (*(u16 *)addr) : "ri" (v));
169 }
170 static inline void wrgs32(u32 v, addr_t addr)
171 {
172 	asm volatile("movl %1,%%gs:%0" : "+m" (*(u32 *)addr) : "ri" (v));
173 }
174 
175 /* Note: these only return true/false, not a signed return value! */
176 static inline bool memcmp_fs(const void *s1, addr_t s2, size_t len)
177 {
178 	bool diff;
179 	asm volatile("fs; repe; cmpsb" CC_SET(nz)
180 		     : CC_OUT(nz) (diff), "+D" (s1), "+S" (s2), "+c" (len));
181 	return diff;
182 }
183 static inline bool memcmp_gs(const void *s1, addr_t s2, size_t len)
184 {
185 	bool diff;
186 	asm volatile("gs; repe; cmpsb" CC_SET(nz)
187 		     : CC_OUT(nz) (diff), "+D" (s1), "+S" (s2), "+c" (len));
188 	return diff;
189 }
190 
191 /* Heap -- available for dynamic lists. */
192 extern char _end[];
193 extern char *HEAP;
194 extern char *heap_end;
195 #define RESET_HEAP() ((void *)( HEAP = _end ))
196 static inline char *__get_heap(size_t s, size_t a, size_t n)
197 {
198 	char *tmp;
199 
200 	HEAP = (char *)(((size_t)HEAP+(a-1)) & ~(a-1));
201 	tmp = HEAP;
202 	HEAP += s*n;
203 	return tmp;
204 }
205 #define GET_HEAP(type, n) \
206 	((type *)__get_heap(sizeof(type),__alignof__(type),(n)))
207 
208 static inline bool heap_free(size_t n)
209 {
210 	return (int)(heap_end-HEAP) >= (int)n;
211 }
212 
213 /* copy.S */
214 
215 void copy_to_fs(addr_t dst, void *src, size_t len);
216 void *copy_from_fs(void *dst, addr_t src, size_t len);
217 void copy_to_gs(addr_t dst, void *src, size_t len);
218 void *copy_from_gs(void *dst, addr_t src, size_t len);
219 
220 /* a20.c */
221 int enable_a20(void);
222 
223 /* apm.c */
224 int query_apm_bios(void);
225 
226 /* bioscall.c */
227 struct biosregs {
228 	union {
229 		struct {
230 			u32 edi;
231 			u32 esi;
232 			u32 ebp;
233 			u32 _esp;
234 			u32 ebx;
235 			u32 edx;
236 			u32 ecx;
237 			u32 eax;
238 			u32 _fsgs;
239 			u32 _dses;
240 			u32 eflags;
241 		};
242 		struct {
243 			u16 di, hdi;
244 			u16 si, hsi;
245 			u16 bp, hbp;
246 			u16 _sp, _hsp;
247 			u16 bx, hbx;
248 			u16 dx, hdx;
249 			u16 cx, hcx;
250 			u16 ax, hax;
251 			u16 gs, fs;
252 			u16 es, ds;
253 			u16 flags, hflags;
254 		};
255 		struct {
256 			u8 dil, dih, edi2, edi3;
257 			u8 sil, sih, esi2, esi3;
258 			u8 bpl, bph, ebp2, ebp3;
259 			u8 _spl, _sph, _esp2, _esp3;
260 			u8 bl, bh, ebx2, ebx3;
261 			u8 dl, dh, edx2, edx3;
262 			u8 cl, ch, ecx2, ecx3;
263 			u8 al, ah, eax2, eax3;
264 		};
265 	};
266 };
267 void intcall(u8 int_no, const struct biosregs *ireg, struct biosregs *oreg);
268 
269 /* cmdline.c */
270 int __cmdline_find_option(unsigned long cmdline_ptr, const char *option, char *buffer, int bufsize);
271 int __cmdline_find_option_bool(unsigned long cmdline_ptr, const char *option);
272 static inline int cmdline_find_option(const char *option, char *buffer, int bufsize)
273 {
274 	unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
275 
276 	if (cmd_line_ptr >= 0x100000)
277 		return -1;      /* inaccessible */
278 
279 	return __cmdline_find_option(cmd_line_ptr, option, buffer, bufsize);
280 }
281 
282 static inline int cmdline_find_option_bool(const char *option)
283 {
284 	unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
285 
286 	if (cmd_line_ptr >= 0x100000)
287 		return -1;      /* inaccessible */
288 
289 	return __cmdline_find_option_bool(cmd_line_ptr, option);
290 }
291 
292 /* cpu.c, cpucheck.c */
293 int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr);
294 int check_knl_erratum(void);
295 int validate_cpu(void);
296 
297 /* early_serial_console.c */
298 extern int early_serial_base;
299 void console_init(void);
300 
301 /* edd.c */
302 void query_edd(void);
303 
304 /* header.S */
305 void __attribute__((noreturn)) die(void);
306 
307 /* memory.c */
308 void detect_memory(void);
309 
310 /* pm.c */
311 void __attribute__((noreturn)) go_to_protected_mode(void);
312 
313 /* pmjump.S */
314 void __attribute__((noreturn))
315 	protected_mode_jump(u32 entrypoint, u32 bootparams);
316 
317 /* printf.c */
318 int sprintf(char *buf, const char *fmt, ...);
319 int vsprintf(char *buf, const char *fmt, va_list args);
320 int printf(const char *fmt, ...);
321 
322 /* regs.c */
323 void initregs(struct biosregs *regs);
324 
325 /* string.c */
326 int strcmp(const char *str1, const char *str2);
327 int strncmp(const char *cs, const char *ct, size_t count);
328 size_t strnlen(const char *s, size_t maxlen);
329 unsigned int atou(const char *s);
330 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base);
331 size_t strlen(const char *s);
332 char *strchr(const char *s, int c);
333 
334 /* tty.c */
335 void puts(const char *);
336 void putchar(int);
337 int getchar(void);
338 void kbd_flush(void);
339 int getchar_timeout(void);
340 
341 /* video.c */
342 void set_video(void);
343 
344 /* video-mode.c */
345 int set_mode(u16 mode);
346 int mode_defined(u16 mode);
347 void probe_cards(int unsafe);
348 
349 /* video-vesa.c */
350 void vesa_store_edid(void);
351 
352 #endif /* __ASSEMBLY__ */
353 
354 #endif /* BOOT_BOOT_H */
355