]> git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blob - arch/x86/boot/boot.h
x86/boot: Fix BSS corruption/overwrite bug in early x86 kernel startup
[mirror_ubuntu-zesty-kernel.git] / arch / x86 / boot / boot.h
1 /* -*- linux-c -*- ------------------------------------------------------- *
2 *
3 * Copyright (C) 1991, 1992 Linus Torvalds
4 * Copyright 2007 rPath, Inc. - All Rights Reserved
5 * Copyright 2009 Intel Corporation; author H. Peter Anvin
6 *
7 * This file is part of the Linux kernel, and is made available under
8 * the terms of the GNU General Public License version 2.
9 *
10 * ----------------------------------------------------------------------- */
11
12 /*
13 * Header file for the real-mode kernel code
14 */
15
16 #ifndef BOOT_BOOT_H
17 #define BOOT_BOOT_H
18
19 #define STACK_SIZE 1024 /* Minimum number of bytes for stack */
20
21 #ifndef __ASSEMBLY__
22
23 #include <stdarg.h>
24 #include <linux/types.h>
25 #include <linux/edd.h>
26 #include <asm/setup.h>
27 #include <asm/asm.h>
28 #include "bitops.h"
29 #include "ctype.h"
30 #include "cpuflags.h"
31
32 /* Useful macros */
33 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
34
35 #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
36
37 extern struct setup_header hdr;
38 extern struct boot_params boot_params;
39
40 #define cpu_relax() asm volatile("rep; nop")
41
42 /* Basic port I/O */
43 static inline void outb(u8 v, u16 port)
44 {
45 asm volatile("outb %0,%1" : : "a" (v), "dN" (port));
46 }
47 static inline u8 inb(u16 port)
48 {
49 u8 v;
50 asm volatile("inb %1,%0" : "=a" (v) : "dN" (port));
51 return v;
52 }
53
54 static inline void outw(u16 v, u16 port)
55 {
56 asm volatile("outw %0,%1" : : "a" (v), "dN" (port));
57 }
58 static inline u16 inw(u16 port)
59 {
60 u16 v;
61 asm volatile("inw %1,%0" : "=a" (v) : "dN" (port));
62 return v;
63 }
64
65 static inline void outl(u32 v, u16 port)
66 {
67 asm volatile("outl %0,%1" : : "a" (v), "dN" (port));
68 }
69 static inline u32 inl(u16 port)
70 {
71 u32 v;
72 asm volatile("inl %1,%0" : "=a" (v) : "dN" (port));
73 return v;
74 }
75
76 static inline void io_delay(void)
77 {
78 const u16 DELAY_PORT = 0x80;
79 asm volatile("outb %%al,%0" : : "dN" (DELAY_PORT));
80 }
81
82 /* These functions are used to reference data in other segments. */
83
84 static inline u16 ds(void)
85 {
86 u16 seg;
87 asm("movw %%ds,%0" : "=rm" (seg));
88 return seg;
89 }
90
91 static inline void set_fs(u16 seg)
92 {
93 asm volatile("movw %0,%%fs" : : "rm" (seg));
94 }
95 static inline u16 fs(void)
96 {
97 u16 seg;
98 asm volatile("movw %%fs,%0" : "=rm" (seg));
99 return seg;
100 }
101
102 static inline void set_gs(u16 seg)
103 {
104 asm volatile("movw %0,%%gs" : : "rm" (seg));
105 }
106 static inline u16 gs(void)
107 {
108 u16 seg;
109 asm volatile("movw %%gs,%0" : "=rm" (seg));
110 return seg;
111 }
112
113 typedef unsigned int addr_t;
114
115 static inline u8 rdfs8(addr_t addr)
116 {
117 u8 v;
118 asm volatile("movb %%fs:%1,%0" : "=q" (v) : "m" (*(u8 *)addr));
119 return v;
120 }
121 static inline u16 rdfs16(addr_t addr)
122 {
123 u16 v;
124 asm volatile("movw %%fs:%1,%0" : "=r" (v) : "m" (*(u16 *)addr));
125 return v;
126 }
127 static inline u32 rdfs32(addr_t addr)
128 {
129 u32 v;
130 asm volatile("movl %%fs:%1,%0" : "=r" (v) : "m" (*(u32 *)addr));
131 return v;
132 }
133
134 static inline void wrfs8(u8 v, addr_t addr)
135 {
136 asm volatile("movb %1,%%fs:%0" : "+m" (*(u8 *)addr) : "qi" (v));
137 }
138 static inline void wrfs16(u16 v, addr_t addr)
139 {
140 asm volatile("movw %1,%%fs:%0" : "+m" (*(u16 *)addr) : "ri" (v));
141 }
142 static inline void wrfs32(u32 v, addr_t addr)
143 {
144 asm volatile("movl %1,%%fs:%0" : "+m" (*(u32 *)addr) : "ri" (v));
145 }
146
147 static inline u8 rdgs8(addr_t addr)
148 {
149 u8 v;
150 asm volatile("movb %%gs:%1,%0" : "=q" (v) : "m" (*(u8 *)addr));
151 return v;
152 }
153 static inline u16 rdgs16(addr_t addr)
154 {
155 u16 v;
156 asm volatile("movw %%gs:%1,%0" : "=r" (v) : "m" (*(u16 *)addr));
157 return v;
158 }
159 static inline u32 rdgs32(addr_t addr)
160 {
161 u32 v;
162 asm volatile("movl %%gs:%1,%0" : "=r" (v) : "m" (*(u32 *)addr));
163 return v;
164 }
165
166 static inline void wrgs8(u8 v, addr_t addr)
167 {
168 asm volatile("movb %1,%%gs:%0" : "+m" (*(u8 *)addr) : "qi" (v));
169 }
170 static inline void wrgs16(u16 v, addr_t addr)
171 {
172 asm volatile("movw %1,%%gs:%0" : "+m" (*(u16 *)addr) : "ri" (v));
173 }
174 static inline void wrgs32(u32 v, addr_t addr)
175 {
176 asm volatile("movl %1,%%gs:%0" : "+m" (*(u32 *)addr) : "ri" (v));
177 }
178
179 /* Note: these only return true/false, not a signed return value! */
180 static inline bool memcmp_fs(const void *s1, addr_t s2, size_t len)
181 {
182 bool diff;
183 asm volatile("fs; repe; cmpsb" CC_SET(nz)
184 : CC_OUT(nz) (diff), "+D" (s1), "+S" (s2), "+c" (len));
185 return diff;
186 }
187 static inline bool memcmp_gs(const void *s1, addr_t s2, size_t len)
188 {
189 bool diff;
190 asm volatile("gs; repe; cmpsb" CC_SET(nz)
191 : CC_OUT(nz) (diff), "+D" (s1), "+S" (s2), "+c" (len));
192 return diff;
193 }
194
195 /* Heap -- available for dynamic lists. */
196 extern char _end[];
197 extern char *HEAP;
198 extern char *heap_end;
199 #define RESET_HEAP() ((void *)( HEAP = _end ))
200 static inline char *__get_heap(size_t s, size_t a, size_t n)
201 {
202 char *tmp;
203
204 HEAP = (char *)(((size_t)HEAP+(a-1)) & ~(a-1));
205 tmp = HEAP;
206 HEAP += s*n;
207 return tmp;
208 }
209 #define GET_HEAP(type, n) \
210 ((type *)__get_heap(sizeof(type),__alignof__(type),(n)))
211
212 static inline bool heap_free(size_t n)
213 {
214 return (int)(heap_end-HEAP) >= (int)n;
215 }
216
217 /* copy.S */
218
219 void copy_to_fs(addr_t dst, void *src, size_t len);
220 void *copy_from_fs(void *dst, addr_t src, size_t len);
221 void copy_to_gs(addr_t dst, void *src, size_t len);
222 void *copy_from_gs(void *dst, addr_t src, size_t len);
223
224 /* a20.c */
225 int enable_a20(void);
226
227 /* apm.c */
228 int query_apm_bios(void);
229
230 /* bioscall.c */
231 struct biosregs {
232 union {
233 struct {
234 u32 edi;
235 u32 esi;
236 u32 ebp;
237 u32 _esp;
238 u32 ebx;
239 u32 edx;
240 u32 ecx;
241 u32 eax;
242 u32 _fsgs;
243 u32 _dses;
244 u32 eflags;
245 };
246 struct {
247 u16 di, hdi;
248 u16 si, hsi;
249 u16 bp, hbp;
250 u16 _sp, _hsp;
251 u16 bx, hbx;
252 u16 dx, hdx;
253 u16 cx, hcx;
254 u16 ax, hax;
255 u16 gs, fs;
256 u16 es, ds;
257 u16 flags, hflags;
258 };
259 struct {
260 u8 dil, dih, edi2, edi3;
261 u8 sil, sih, esi2, esi3;
262 u8 bpl, bph, ebp2, ebp3;
263 u8 _spl, _sph, _esp2, _esp3;
264 u8 bl, bh, ebx2, ebx3;
265 u8 dl, dh, edx2, edx3;
266 u8 cl, ch, ecx2, ecx3;
267 u8 al, ah, eax2, eax3;
268 };
269 };
270 };
271 void intcall(u8 int_no, const struct biosregs *ireg, struct biosregs *oreg);
272
273 /* cmdline.c */
274 int __cmdline_find_option(unsigned long cmdline_ptr, const char *option, char *buffer, int bufsize);
275 int __cmdline_find_option_bool(unsigned long cmdline_ptr, const char *option);
276 static inline int cmdline_find_option(const char *option, char *buffer, int bufsize)
277 {
278 unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
279
280 if (cmd_line_ptr >= 0x100000)
281 return -1; /* inaccessible */
282
283 return __cmdline_find_option(cmd_line_ptr, option, buffer, bufsize);
284 }
285
286 static inline int cmdline_find_option_bool(const char *option)
287 {
288 unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
289
290 if (cmd_line_ptr >= 0x100000)
291 return -1; /* inaccessible */
292
293 return __cmdline_find_option_bool(cmd_line_ptr, option);
294 }
295
296 /* cpu.c, cpucheck.c */
297 int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr);
298 int check_knl_erratum(void);
299 int validate_cpu(void);
300
301 /* early_serial_console.c */
302 extern int early_serial_base;
303 void console_init(void);
304
305 /* edd.c */
306 void query_edd(void);
307
308 /* header.S */
309 void __attribute__((noreturn)) die(void);
310
311 /* memory.c */
312 int detect_memory(void);
313
314 /* pm.c */
315 void __attribute__((noreturn)) go_to_protected_mode(void);
316
317 /* pmjump.S */
318 void __attribute__((noreturn))
319 protected_mode_jump(u32 entrypoint, u32 bootparams);
320
321 /* printf.c */
322 int sprintf(char *buf, const char *fmt, ...);
323 int vsprintf(char *buf, const char *fmt, va_list args);
324 int printf(const char *fmt, ...);
325
326 /* regs.c */
327 void initregs(struct biosregs *regs);
328
329 /* string.c */
330 int strcmp(const char *str1, const char *str2);
331 int strncmp(const char *cs, const char *ct, size_t count);
332 size_t strnlen(const char *s, size_t maxlen);
333 unsigned int atou(const char *s);
334 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base);
335 size_t strlen(const char *s);
336
337 /* tty.c */
338 void puts(const char *);
339 void putchar(int);
340 int getchar(void);
341 void kbd_flush(void);
342 int getchar_timeout(void);
343
344 /* video.c */
345 void set_video(void);
346
347 /* video-mode.c */
348 int set_mode(u16 mode);
349 int mode_defined(u16 mode);
350 void probe_cards(int unsafe);
351
352 /* video-vesa.c */
353 void vesa_store_edid(void);
354
355 #endif /* __ASSEMBLY__ */
356
357 #endif /* BOOT_BOOT_H */