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#include <cpu/x86/post_code.h>
.section ".text"
.code32
.globl _start
_start:
cli
lgdt %cs:gdtaddr
ljmp $0x10, $1f
1: movl $0x18, %eax
movl %eax, %ds
movl %eax, %es
movl %eax, %ss
movl %eax, %fs
movl %eax, %gs
post_code(POST_ENTRY_C_START) /* post 13 */
/** poison the stack. Code should not count on the
* stack being full of zeros. This stack poisoning
* recently uncovered a bug in the broadcast SIPI
* code.
*/
cld
leal _stack, %edi
movl $_estack, %ecx
subl %edi, %ecx
shrl $2, %ecx /* it is 32 bit aligned, right? */
movl $0xDEADBEEF, %eax
rep
stosl
/** clear bss, which unlike the stack is zero by definition */
leal _bss, %edi
movl $_ebss, %ecx
subl %edi, %ecx
jz .Lnobss
shrl $2, %ecx /* it is 32 bit aligned, right? */
xorl %eax, %eax
rep
stosl
.Lnobss:
/* set new stack */
movl $_estack, %esp
/* Push the cpu index and struct cpu */
pushl $0
pushl $0
/* push the boot_complete flag */
pushl %ebp
/* Save the stack location */
movl %esp, %ebp
/* Initialize the Interrupt Descriptor table */
leal _idt, %edi
leal vec0, %ebx
movl $(0x10 << 16), %eax /* cs selector */
1: movw %bx, %ax
movl %ebx, %edx
movw $0x8E00, %dx /* Interrupt gate - dpl=0, present */
movl %eax, 0(%edi)
movl %edx, 4(%edi)
addl $6, %ebx
addl $8, %edi
cmpl $_idt_end, %edi
jne 1b
/* Load the Interrupt descriptor table */
lidt idtarg
/*
* Now we are finished. Memory is up, data is copied and
* bss is cleared. Now we call the main routine and
* let it do the rest.
*/
post_code(POST_PRE_HARDWAREMAIN) /* post fe */
/* Restore the stack location */
movl %ebp, %esp
#if CONFIG_GDB_WAIT == 1
call gdb_stub_breakpoint
#endif
/* The boot_complete flag has already been pushed */
call hardwaremain
/* NOTREACHED */
.Lhlt:
post_code(POST_DEAD_CODE) /* post ee */
hlt
jmp .Lhlt
vec0:
pushl $0 /* error code */
pushl $0 /* vector */
jmp int_hand
vec1:
pushl $0 /* error code */
pushl $1 /* vector */
jmp int_hand
vec2:
pushl $0 /* error code */
pushl $2 /* vector */
jmp int_hand
vec3:
pushl $0 /* error code */
pushl $3 /* vector */
jmp int_hand
vec4:
pushl $0 /* error code */
pushl $4 /* vector */
jmp int_hand
vec5:
pushl $0 /* error code */
pushl $5 /* vector */
jmp int_hand
vec6:
pushl $0 /* error code */
pushl $6 /* vector */
jmp int_hand
vec7:
pushl $0 /* error code */
pushl $7 /* vector */
jmp int_hand
vec8:
/* error code */
pushl $8 /* vector */
jmp int_hand
.word 0x9090
vec9:
pushl $0 /* error code */
pushl $9 /* vector */
jmp int_hand
vec10:
/* error code */
pushl $10 /* vector */
jmp int_hand
.word 0x9090
vec11:
/* error code */
pushl $11 /* vector */
jmp int_hand
.word 0x9090
vec12:
/* error code */
pushl $12 /* vector */
jmp int_hand
.word 0x9090
vec13:
/* error code */
pushl $13 /* vector */
jmp int_hand
.word 0x9090
vec14:
/* error code */
pushl $14 /* vector */
jmp int_hand
.word 0x9090
vec15:
pushl $0 /* error code */
pushl $15 /* vector */
jmp int_hand
vec16:
pushl $0 /* error code */
pushl $16 /* vector */
jmp int_hand
vec17:
/* error code */
pushl $17 /* vector */
jmp int_hand
.word 0x9090
vec18:
pushl $0 /* error code */
pushl $18 /* vector */
jmp int_hand
vec19:
pushl $0 /* error code */
pushl $19 /* vector */
jmp int_hand
int_hand:
/* At this point on the stack there is:
* 0(%esp) vector
* 4(%esp) error code
* 8(%esp) eip
* 12(%esp) cs
* 16(%esp) eflags
*/
pushl %edi
pushl %esi
pushl %ebp
/* Original stack pointer */
leal 32(%esp), %ebp
pushl %ebp
pushl %ebx
pushl %edx
pushl %ecx
pushl %eax
pushl %esp /* Pointer to structure on the stack */
call x86_exception
pop %eax /* Drop the pointer */
popl %eax
popl %ecx
popl %edx
popl %ebx
popl %ebp /* Ignore saved %esp value */
popl %ebp
popl %esi
popl %edi
addl $8, %esp /* pop of the vector and error code */
iret
#if CONFIG_GDB_WAIT == 1
.globl gdb_stub_breakpoint
gdb_stub_breakpoint:
popl %eax /* Return address */
pushfl
pushl %cs
pushl %eax /* Return address */
pushl $0 /* No error code */
pushl $32 /* vector 32 is user defined */
jmp int_hand
#endif
.globl gdt, gdt_end, gdt_limit, idtarg
gdt_limit = gdt_end - gdt - 1 /* compute the table limit */
gdtaddr:
.word gdt_limit
.long gdt /* we know the offset */
.data
/* This is the gdt for GCC part of coreboot.
* It is different from the gdt in ROMCC/ASM part of coreboot
* which is defined in entry32.inc
*
* When the machine is initially started, we use a very simple
* gdt from rom (that in entry32.inc) which only contains those
* entries we need for protected mode.
*
* When we're executing code from RAM, we want to do more complex
* stuff, like initializing PCI option roms in real mode, or doing
* a resume from a suspend to ram.
*/
gdt:
/* selgdt 0, unused */
.word 0x0000, 0x0000 /* dummy */
.byte 0x00, 0x00, 0x00, 0x00
/* selgdt 8, unused */
.word 0x0000, 0x0000 /* dummy */
.byte 0x00, 0x00, 0x00, 0x00
/* selgdt 0x10, flat code segment */
.word 0xffff, 0x0000
.byte 0x00, 0x9b, 0xcf, 0x00 /* G=1 and 0x0f, So we get 4Gbytes for limit */
/* selgdt 0x18, flat data segment */
.word 0xffff, 0x0000
.byte 0x00, 0x93, 0xcf, 0x00
/* selgdt 0x20, unused */
.word 0x0000, 0x0000 /* dummy */
.byte 0x00, 0x00, 0x00, 0x00
/* The next two entries are used for executing VGA option ROMs */
/* selgdt 0x28 16 bit 64k code at 0x00000000 */
.word 0xffff, 0x0000
.byte 0, 0x9a, 0, 0
/* selgdt 0x30 16 bit 64k data at 0x00000000 */
.word 0xffff, 0x0000
.byte 0, 0x92, 0, 0
/* The next two entries are used for ACPI S3 RESUME */
/* selgdt 0x38, flat data segment 16 bit */
.word 0x0000, 0x0000 /* dummy */
.byte 0x00, 0x93, 0x8f, 0x00 /* G=1 and 0x0f, So we get 4Gbytes for limit */
/* selgdt 0x40, flat code segment 16 bit */
.word 0xffff, 0x0000
.byte 0x00, 0x9b, 0x8f, 0x00 /* G=1 and 0x0f, So we get 4Gbytes for limit */
gdt_end:
idtarg:
.word _idt_end - _idt - 1 /* limit */
.long _idt
.word 0
_idt:
.fill 20, 8, 0 # idt is uninitialized
_idt_end:
.previous
.code32
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