linux/arch/x86/boot/boot.h
H. Peter Anvin 6b6815c6d5 x86 setup: handle boot loaders which set up the stack incorrectly
Apparently some specific versions of LILO enter the kernel with a
stack pointer that doesn't match the rest of the segments.  Make our
best attempt at untangling the resulting mess.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2007-10-25 19:55:03 -07:00

297 lines
6.3 KiB
C

/* -*- linux-c -*- ------------------------------------------------------- *
*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright 2007 rPath, Inc. - All Rights Reserved
*
* This file is part of the Linux kernel, and is made available under
* the terms of the GNU General Public License version 2.
*
* ----------------------------------------------------------------------- */
/*
* arch/i386/boot/boot.h
*
* Header file for the real-mode kernel code
*/
#ifndef BOOT_BOOT_H
#define BOOT_BOOT_H
#define STACK_SIZE 512 /* Minimum number of bytes for stack */
#ifndef __ASSEMBLY__
#include <stdarg.h>
#include <linux/types.h>
#include <linux/edd.h>
#include <asm/boot.h>
#include <asm/setup.h>
/* Useful macros */
#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
extern struct setup_header hdr;
extern struct boot_params boot_params;
/* Basic port I/O */
static inline void outb(u8 v, u16 port)
{
asm volatile("outb %0,%1" : : "a" (v), "dN" (port));
}
static inline u8 inb(u16 port)
{
u8 v;
asm volatile("inb %1,%0" : "=a" (v) : "dN" (port));
return v;
}
static inline void outw(u16 v, u16 port)
{
asm volatile("outw %0,%1" : : "a" (v), "dN" (port));
}
static inline u16 inw(u16 port)
{
u16 v;
asm volatile("inw %1,%0" : "=a" (v) : "dN" (port));
return v;
}
static inline void outl(u32 v, u16 port)
{
asm volatile("outl %0,%1" : : "a" (v), "dN" (port));
}
static inline u32 inl(u32 port)
{
u32 v;
asm volatile("inl %1,%0" : "=a" (v) : "dN" (port));
return v;
}
static inline void io_delay(void)
{
const u16 DELAY_PORT = 0x80;
asm volatile("outb %%al,%0" : : "dN" (DELAY_PORT));
}
/* These functions are used to reference data in other segments. */
static inline u16 ds(void)
{
u16 seg;
asm("movw %%ds,%0" : "=rm" (seg));
return seg;
}
static inline void set_fs(u16 seg)
{
asm volatile("movw %0,%%fs" : : "rm" (seg));
}
static inline u16 fs(void)
{
u16 seg;
asm volatile("movw %%fs,%0" : "=rm" (seg));
return seg;
}
static inline void set_gs(u16 seg)
{
asm volatile("movw %0,%%gs" : : "rm" (seg));
}
static inline u16 gs(void)
{
u16 seg;
asm volatile("movw %%gs,%0" : "=rm" (seg));
return seg;
}
typedef unsigned int addr_t;
static inline u8 rdfs8(addr_t addr)
{
u8 v;
asm volatile("movb %%fs:%1,%0" : "=r" (v) : "m" (*(u8 *)addr));
return v;
}
static inline u16 rdfs16(addr_t addr)
{
u16 v;
asm volatile("movw %%fs:%1,%0" : "=r" (v) : "m" (*(u16 *)addr));
return v;
}
static inline u32 rdfs32(addr_t addr)
{
u32 v;
asm volatile("movl %%fs:%1,%0" : "=r" (v) : "m" (*(u32 *)addr));
return v;
}
static inline void wrfs8(u8 v, addr_t addr)
{
asm volatile("movb %1,%%fs:%0" : "+m" (*(u8 *)addr) : "r" (v));
}
static inline void wrfs16(u16 v, addr_t addr)
{
asm volatile("movw %1,%%fs:%0" : "+m" (*(u16 *)addr) : "r" (v));
}
static inline void wrfs32(u32 v, addr_t addr)
{
asm volatile("movl %1,%%fs:%0" : "+m" (*(u32 *)addr) : "r" (v));
}
static inline u8 rdgs8(addr_t addr)
{
u8 v;
asm volatile("movb %%gs:%1,%0" : "=r" (v) : "m" (*(u8 *)addr));
return v;
}
static inline u16 rdgs16(addr_t addr)
{
u16 v;
asm volatile("movw %%gs:%1,%0" : "=r" (v) : "m" (*(u16 *)addr));
return v;
}
static inline u32 rdgs32(addr_t addr)
{
u32 v;
asm volatile("movl %%gs:%1,%0" : "=r" (v) : "m" (*(u32 *)addr));
return v;
}
static inline void wrgs8(u8 v, addr_t addr)
{
asm volatile("movb %1,%%gs:%0" : "+m" (*(u8 *)addr) : "r" (v));
}
static inline void wrgs16(u16 v, addr_t addr)
{
asm volatile("movw %1,%%gs:%0" : "+m" (*(u16 *)addr) : "r" (v));
}
static inline void wrgs32(u32 v, addr_t addr)
{
asm volatile("movl %1,%%gs:%0" : "+m" (*(u32 *)addr) : "r" (v));
}
/* Note: these only return true/false, not a signed return value! */
static inline int memcmp(const void *s1, const void *s2, size_t len)
{
u8 diff;
asm("repe; cmpsb; setnz %0"
: "=qm" (diff), "+D" (s1), "+S" (s2), "+c" (len));
return diff;
}
static inline int memcmp_fs(const void *s1, addr_t s2, size_t len)
{
u8 diff;
asm volatile("fs; repe; cmpsb; setnz %0"
: "=qm" (diff), "+D" (s1), "+S" (s2), "+c" (len));
return diff;
}
static inline int memcmp_gs(const void *s1, addr_t s2, size_t len)
{
u8 diff;
asm volatile("gs; repe; cmpsb; setnz %0"
: "=qm" (diff), "+D" (s1), "+S" (s2), "+c" (len));
return diff;
}
static inline int isdigit(int ch)
{
return (ch >= '0') && (ch <= '9');
}
/* Heap -- available for dynamic lists. */
extern char _end[];
extern char *HEAP;
extern char *heap_end;
#define RESET_HEAP() ((void *)( HEAP = _end ))
static inline char *__get_heap(size_t s, size_t a, size_t n)
{
char *tmp;
HEAP = (char *)(((size_t)HEAP+(a-1)) & ~(a-1));
tmp = HEAP;
HEAP += s*n;
return tmp;
}
#define GET_HEAP(type, n) \
((type *)__get_heap(sizeof(type),__alignof__(type),(n)))
static inline int heap_free(void)
{
return heap_end-HEAP;
}
/* copy.S */
void copy_to_fs(addr_t dst, void *src, size_t len);
void *copy_from_fs(void *dst, addr_t src, size_t len);
void copy_to_gs(addr_t dst, void *src, size_t len);
void *copy_from_gs(void *dst, addr_t src, size_t len);
void *memcpy(void *dst, void *src, size_t len);
void *memset(void *dst, int c, size_t len);
#define memcpy(d,s,l) __builtin_memcpy(d,s,l)
#define memset(d,c,l) __builtin_memset(d,c,l)
/* a20.c */
int enable_a20(void);
/* apm.c */
int query_apm_bios(void);
/* cmdline.c */
int cmdline_find_option(const char *option, char *buffer, int bufsize);
/* cpu.c, cpucheck.c */
int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr);
int validate_cpu(void);
/* edd.c */
void query_edd(void);
/* header.S */
void __attribute__((noreturn)) die(void);
/* mca.c */
int query_mca(void);
/* memory.c */
int detect_memory(void);
/* pm.c */
void __attribute__((noreturn)) go_to_protected_mode(void);
/* pmjump.S */
void __attribute__((noreturn))
protected_mode_jump(u32 entrypoint, u32 bootparams);
/* printf.c */
int sprintf(char *buf, const char *fmt, ...);
int vsprintf(char *buf, const char *fmt, va_list args);
int printf(const char *fmt, ...);
/* string.c */
int strcmp(const char *str1, const char *str2);
size_t strnlen(const char *s, size_t maxlen);
unsigned int atou(const char *s);
/* tty.c */
void puts(const char *);
void putchar(int);
int getchar(void);
void kbd_flush(void);
int getchar_timeout(void);
/* video.c */
void set_video(void);
/* video-vesa.c */
void vesa_store_edid(void);
/* voyager.c */
int query_voyager(void);
#endif /* __ASSEMBLY__ */
#endif /* BOOT_BOOT_H */