boot.h

  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
 34extern struct setup_header hdr;
 35extern struct boot_params boot_params;
 36
 37#define cpu_relax()	asm volatile("pause")
 38
 39static 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
 47static inline u16 ds(void)
 48{
 49	u16 seg;
 50	asm("movw %%ds,%0" : "=rm" (seg));
 51	return seg;
 52}
 53
 54static inline void set_fs(u16 seg)
 55{
 56	asm volatile("movw %0,%%fs" : : "rm" (seg));
 57}
 58static inline u16 fs(void)
 59{
 60	u16 seg;
 61	asm volatile("movw %%fs,%0" : "=rm" (seg));
 62	return seg;
 63}
 64
 65static inline void set_gs(u16 seg)
 66{
 67	asm volatile("movw %0,%%gs" : : "rm" (seg));
 68}
 69static inline u16 gs(void)
 70{
 71	u16 seg;
 72	asm volatile("movw %%gs,%0" : "=rm" (seg));
 73	return seg;
 74}
 75
 76typedef unsigned int addr_t;
 77
 78static 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}
 85static 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}
 92static 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
100static 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}
105static 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}
110static 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
116static 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}
123static 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}
130static 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
138static 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}
143static 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}
148static 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! */
155static 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}
162static 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. */
171extern char _end[];
172extern char *HEAP;
173extern char *heap_end;
174#define RESET_HEAP() ((void *)( HEAP = _end ))
175static 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
187static inline bool heap_free(size_t n)
188{
189	return (int)(heap_end-HEAP) >= (int)n;
190}
191
192/* copy.S */
193
194void copy_to_fs(addr_t dst, void *src, size_t len);
195void *copy_from_fs(void *dst, addr_t src, size_t len);
196
197/* a20.c */
198int enable_a20(void);
199
200/* apm.c */
201int query_apm_bios(void);
202
203/* bioscall.c */
204struct 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};
244void intcall(u8 int_no, const struct biosregs *ireg, struct biosregs *oreg);
245
246/* cmdline.c */
247int __cmdline_find_option(unsigned long cmdline_ptr, const char *option, char *buffer, int bufsize);
248int __cmdline_find_option_bool(unsigned long cmdline_ptr, const char *option);
249static 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
259static 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 */
270int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr);
271int check_knl_erratum(void);
272int validate_cpu(void);
273
274/* early_serial_console.c */
275extern int early_serial_base;
276void console_init(void);
277
278/* edd.c */
279void query_edd(void);
280
281/* header.S */
282void __attribute__((noreturn)) die(void);
283
284/* memory.c */
285void detect_memory(void);
286
287/* pm.c */
288void __attribute__((noreturn)) go_to_protected_mode(void);
289
290/* pmjump.S */
291void __attribute__((noreturn))
292	protected_mode_jump(u32 entrypoint, u32 bootparams);
293
294/* printf.c */
295int sprintf(char *buf, const char *fmt, ...);
296int vsprintf(char *buf, const char *fmt, va_list args);
297int printf(const char *fmt, ...);
298
299/* regs.c */
300void initregs(struct biosregs *regs);
301
302/* string.c */
303int strcmp(const char *str1, const char *str2);
304int strncmp(const char *cs, const char *ct, size_t count);
305size_t strnlen(const char *s, size_t maxlen);
306unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base);
307size_t strlen(const char *s);
308char *strchr(const char *s, int c);
309
310/* tty.c */
311void puts(const char *);
312void putchar(int);
313int getchar(void);
314void kbd_flush(void);
315int getchar_timeout(void);
316
317/* video.c */
318void set_video(void);
319
320/* video-mode.c */
321int set_mode(u16 mode);
322int mode_defined(u16 mode);
323void probe_cards(int unsafe);
324
325/* video-vesa.c */
326void vesa_store_edid(void);
327
328#endif /* __ASSEMBLER__ */
329
330#endif /* BOOT_BOOT_H */