xref: /kernel/linux/linux-5.10/arch/x86/boot/boot.h (revision 8c2ecf20)
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 <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
33extern struct setup_header hdr;
34extern struct boot_params boot_params;
35
36#define cpu_relax()	asm volatile("rep; nop")
37
38/* Basic port I/O */
39static inline void outb(u8 v, u16 port)
40{
41	asm volatile("outb %0,%1" : : "a" (v), "dN" (port));
42}
43static inline u8 inb(u16 port)
44{
45	u8 v;
46	asm volatile("inb %1,%0" : "=a" (v) : "dN" (port));
47	return v;
48}
49
50static inline void outw(u16 v, u16 port)
51{
52	asm volatile("outw %0,%1" : : "a" (v), "dN" (port));
53}
54static inline u16 inw(u16 port)
55{
56	u16 v;
57	asm volatile("inw %1,%0" : "=a" (v) : "dN" (port));
58	return v;
59}
60
61static inline void outl(u32 v, u16 port)
62{
63	asm volatile("outl %0,%1" : : "a" (v), "dN" (port));
64}
65static inline u32 inl(u16 port)
66{
67	u32 v;
68	asm volatile("inl %1,%0" : "=a" (v) : "dN" (port));
69	return v;
70}
71
72static 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
80static inline u16 ds(void)
81{
82	u16 seg;
83	asm("movw %%ds,%0" : "=rm" (seg));
84	return seg;
85}
86
87static inline void set_fs(u16 seg)
88{
89	asm volatile("movw %0,%%fs" : : "rm" (seg));
90}
91static inline u16 fs(void)
92{
93	u16 seg;
94	asm volatile("movw %%fs,%0" : "=rm" (seg));
95	return seg;
96}
97
98static inline void set_gs(u16 seg)
99{
100	asm volatile("movw %0,%%gs" : : "rm" (seg));
101}
102static inline u16 gs(void)
103{
104	u16 seg;
105	asm volatile("movw %%gs,%0" : "=rm" (seg));
106	return seg;
107}
108
109typedef unsigned int addr_t;
110
111static inline u8 rdfs8(addr_t addr)
112{
113	u8 *ptr = (u8 *)absolute_pointer(addr);
114	u8 v;
115	asm volatile("movb %%fs:%1,%0" : "=q" (v) : "m" (*ptr));
116	return v;
117}
118static inline u16 rdfs16(addr_t addr)
119{
120	u16 *ptr = (u16 *)absolute_pointer(addr);
121	u16 v;
122	asm volatile("movw %%fs:%1,%0" : "=r" (v) : "m" (*ptr));
123	return v;
124}
125static inline u32 rdfs32(addr_t addr)
126{
127	u32 *ptr = (u32 *)absolute_pointer(addr);
128	u32 v;
129	asm volatile("movl %%fs:%1,%0" : "=r" (v) : "m" (*ptr));
130	return v;
131}
132
133static inline void wrfs8(u8 v, addr_t addr)
134{
135	u8 *ptr = (u8 *)absolute_pointer(addr);
136	asm volatile("movb %1,%%fs:%0" : "+m" (*ptr) : "qi" (v));
137}
138static inline void wrfs16(u16 v, addr_t addr)
139{
140	u16 *ptr = (u16 *)absolute_pointer(addr);
141	asm volatile("movw %1,%%fs:%0" : "+m" (*ptr) : "ri" (v));
142}
143static inline void wrfs32(u32 v, addr_t addr)
144{
145	u32 *ptr = (u32 *)absolute_pointer(addr);
146	asm volatile("movl %1,%%fs:%0" : "+m" (*ptr) : "ri" (v));
147}
148
149static inline u8 rdgs8(addr_t addr)
150{
151	u8 *ptr = (u8 *)absolute_pointer(addr);
152	u8 v;
153	asm volatile("movb %%gs:%1,%0" : "=q" (v) : "m" (*ptr));
154	return v;
155}
156static inline u16 rdgs16(addr_t addr)
157{
158	u16 *ptr = (u16 *)absolute_pointer(addr);
159	u16 v;
160	asm volatile("movw %%gs:%1,%0" : "=r" (v) : "m" (*ptr));
161	return v;
162}
163static inline u32 rdgs32(addr_t addr)
164{
165	u32 *ptr = (u32 *)absolute_pointer(addr);
166	u32 v;
167	asm volatile("movl %%gs:%1,%0" : "=r" (v) : "m" (*ptr));
168	return v;
169}
170
171static inline void wrgs8(u8 v, addr_t addr)
172{
173	u8 *ptr = (u8 *)absolute_pointer(addr);
174	asm volatile("movb %1,%%gs:%0" : "+m" (*ptr) : "qi" (v));
175}
176static inline void wrgs16(u16 v, addr_t addr)
177{
178	u16 *ptr = (u16 *)absolute_pointer(addr);
179	asm volatile("movw %1,%%gs:%0" : "+m" (*ptr) : "ri" (v));
180}
181static inline void wrgs32(u32 v, addr_t addr)
182{
183	u32 *ptr = (u32 *)absolute_pointer(addr);
184	asm volatile("movl %1,%%gs:%0" : "+m" (*ptr) : "ri" (v));
185}
186
187/* Note: these only return true/false, not a signed return value! */
188static inline bool memcmp_fs(const void *s1, addr_t s2, size_t len)
189{
190	bool diff;
191	asm volatile("fs; repe; cmpsb" CC_SET(nz)
192		     : CC_OUT(nz) (diff), "+D" (s1), "+S" (s2), "+c" (len));
193	return diff;
194}
195static inline bool memcmp_gs(const void *s1, addr_t s2, size_t len)
196{
197	bool diff;
198	asm volatile("gs; repe; cmpsb" CC_SET(nz)
199		     : CC_OUT(nz) (diff), "+D" (s1), "+S" (s2), "+c" (len));
200	return diff;
201}
202
203/* Heap -- available for dynamic lists. */
204extern char _end[];
205extern char *HEAP;
206extern char *heap_end;
207#define RESET_HEAP() ((void *)( HEAP = _end ))
208static inline char *__get_heap(size_t s, size_t a, size_t n)
209{
210	char *tmp;
211
212	HEAP = (char *)(((size_t)HEAP+(a-1)) & ~(a-1));
213	tmp = HEAP;
214	HEAP += s*n;
215	return tmp;
216}
217#define GET_HEAP(type, n) \
218	((type *)__get_heap(sizeof(type),__alignof__(type),(n)))
219
220static inline bool heap_free(size_t n)
221{
222	return (int)(heap_end-HEAP) >= (int)n;
223}
224
225/* copy.S */
226
227void copy_to_fs(addr_t dst, void *src, size_t len);
228void *copy_from_fs(void *dst, addr_t src, size_t len);
229void copy_to_gs(addr_t dst, void *src, size_t len);
230void *copy_from_gs(void *dst, addr_t src, size_t len);
231
232/* a20.c */
233int enable_a20(void);
234
235/* apm.c */
236int query_apm_bios(void);
237
238/* bioscall.c */
239struct biosregs {
240	union {
241		struct {
242			u32 edi;
243			u32 esi;
244			u32 ebp;
245			u32 _esp;
246			u32 ebx;
247			u32 edx;
248			u32 ecx;
249			u32 eax;
250			u32 _fsgs;
251			u32 _dses;
252			u32 eflags;
253		};
254		struct {
255			u16 di, hdi;
256			u16 si, hsi;
257			u16 bp, hbp;
258			u16 _sp, _hsp;
259			u16 bx, hbx;
260			u16 dx, hdx;
261			u16 cx, hcx;
262			u16 ax, hax;
263			u16 gs, fs;
264			u16 es, ds;
265			u16 flags, hflags;
266		};
267		struct {
268			u8 dil, dih, edi2, edi3;
269			u8 sil, sih, esi2, esi3;
270			u8 bpl, bph, ebp2, ebp3;
271			u8 _spl, _sph, _esp2, _esp3;
272			u8 bl, bh, ebx2, ebx3;
273			u8 dl, dh, edx2, edx3;
274			u8 cl, ch, ecx2, ecx3;
275			u8 al, ah, eax2, eax3;
276		};
277	};
278};
279void intcall(u8 int_no, const struct biosregs *ireg, struct biosregs *oreg);
280
281/* cmdline.c */
282int __cmdline_find_option(unsigned long cmdline_ptr, const char *option, char *buffer, int bufsize);
283int __cmdline_find_option_bool(unsigned long cmdline_ptr, const char *option);
284static inline int cmdline_find_option(const char *option, char *buffer, int bufsize)
285{
286	unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
287
288	if (cmd_line_ptr >= 0x100000)
289		return -1;      /* inaccessible */
290
291	return __cmdline_find_option(cmd_line_ptr, option, buffer, bufsize);
292}
293
294static inline int cmdline_find_option_bool(const char *option)
295{
296	unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
297
298	if (cmd_line_ptr >= 0x100000)
299		return -1;      /* inaccessible */
300
301	return __cmdline_find_option_bool(cmd_line_ptr, option);
302}
303
304/* cpu.c, cpucheck.c */
305int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr);
306int check_knl_erratum(void);
307int validate_cpu(void);
308
309/* early_serial_console.c */
310extern int early_serial_base;
311void console_init(void);
312
313/* edd.c */
314void query_edd(void);
315
316/* header.S */
317void __attribute__((noreturn)) die(void);
318
319/* memory.c */
320void detect_memory(void);
321
322/* pm.c */
323void __attribute__((noreturn)) go_to_protected_mode(void);
324
325/* pmjump.S */
326void __attribute__((noreturn))
327	protected_mode_jump(u32 entrypoint, u32 bootparams);
328
329/* printf.c */
330int sprintf(char *buf, const char *fmt, ...);
331int vsprintf(char *buf, const char *fmt, va_list args);
332int printf(const char *fmt, ...);
333
334/* regs.c */
335void initregs(struct biosregs *regs);
336
337/* string.c */
338int strcmp(const char *str1, const char *str2);
339int strncmp(const char *cs, const char *ct, size_t count);
340size_t strnlen(const char *s, size_t maxlen);
341unsigned int atou(const char *s);
342unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base);
343size_t strlen(const char *s);
344char *strchr(const char *s, int c);
345
346/* tty.c */
347void puts(const char *);
348void putchar(int);
349int getchar(void);
350void kbd_flush(void);
351int getchar_timeout(void);
352
353/* video.c */
354void set_video(void);
355
356/* video-mode.c */
357int set_mode(u16 mode);
358int mode_defined(u16 mode);
359void probe_cards(int unsafe);
360
361/* video-vesa.c */
362void vesa_store_edid(void);
363
364#endif /* __ASSEMBLY__ */
365
366#endif /* BOOT_BOOT_H */
367