diff options
| author | Thomas Bushnell <thomas@gnu.org> | 1997-02-25 21:28:37 +0000 |
|---|---|---|
| committer | Thomas Bushnell <thomas@gnu.org> | 1997-02-25 21:28:37 +0000 |
| commit | f07a4c844da9f0ecae5bbee1ab94be56505f26f7 (patch) | |
| tree | 12b07c7e578fc1a5f53dbfde2632408491ff2a70 /i386/i386at/boothdr.S | |
Initial source
Diffstat (limited to 'i386/i386at/boothdr.S')
| -rw-r--r-- | i386/i386at/boothdr.S | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/i386/i386at/boothdr.S b/i386/i386at/boothdr.S new file mode 100644 index 0000000..de80753 --- /dev/null +++ b/i386/i386at/boothdr.S @@ -0,0 +1,62 @@ + +#include <mach/machine/asm.h> + +#include "i386asm.h" + + .text + + /* We should never be entered this way. */ + .globl start,_start +start: +_start: + jmp boot_entry + + /* MultiBoot header - see multiboot.h. */ +#define MULTIBOOT_MAGIC 0x1BADB002 +#ifdef __ELF__ +#define MULTIBOOT_FLAGS 0x00000002 +#else /* __ELF__ */ +#define MULTIBOOT_FLAGS 0x00010002 +#endif /* __ELF__ */ + P2ALIGN(2) +boot_hdr: + .long MULTIBOOT_MAGIC + .long MULTIBOOT_FLAGS + /* + * The next item here is the checksum. + * XX this works OK until we need at least the 30th bit. + */ + .long - (MULTIBOOT_MAGIC+MULTIBOOT_FLAGS) +#ifndef __ELF__ /* a.out kludge */ + .long boot_hdr /* header_addr */ + .long _start /* load_addr */ + .long _edata /* load_end_addr */ + .long _end /* bss_end_addr */ + .long boot_entry /* entry */ +#endif /* __ELF__ */ + +boot_entry: + + /* Switch to our own interrupt stack. */ + movl $_intstack+INTSTACK_SIZE,%esp + + /* Reset EFLAGS to a known state. */ + pushl $0 + popf + + /* Clear uninitialized data. */ + lea _edata,%edi + lea _end,%ecx + subl %edi,%ecx + xorl %eax,%eax + rep + stosb + + /* Push the boot_info pointer to be the second argument. */ + pushl %ebx + + /* Jump into C code. */ + call EXT(c_boot_entry) + + .comm _intstack,INTSTACK_SIZE + |