#include .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 */ /** clear stack */ cld leal _stack, %edi movl $_estack, %ecx subl %edi, %ecx shrl $2, %ecx /* it is 32 bit aligned, right? */ xorl %eax, %eax rep stosl /** clear bss */ 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 /* 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_STUB == 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