/* For starting coreboot in protected mode */ #include #include .code32 /* This is the GDT for the ROM stage part of coreboot. It * is different from the RAM stage GDT which is defined in * c_start.S */ .align 4 .globl gdtptr gdt: gdtptr: .word gdt_end - gdt -1 /* compute the table limit */ .long gdt /* we know the offset */ .word 0 /* selgdt 0x08, flat code segment */ .word 0xffff, 0x0000 .byte 0x00, 0x9b, 0xcf, 0x00 /* G=1 and 0x0f, So we get 4Gbytes for limit */ /* selgdt 0x10,flat data segment */ .word 0xffff, 0x0000 .byte 0x00, 0x93, 0xcf, 0x00 /* selgdt 0x18, flat code segment (64-bit) */ .word 0xffff, 0x0000 .byte 0x00, 0x9b, 0xaf, 0x00 gdt_end: /* * When we come here we are in protected mode. We expand * the stack and copies the data segment from ROM to the * memory. * * After that, we call the chipset bootstrap routine that * does what is left of the chipset initialization. * * NOTE aligned to 4 so that we are sure that the prefetch * cache will be reloaded. */ .align 4 .globl protected_start protected_start: lgdt %cs:gdtptr ljmp $ROM_CODE_SEG, $__protected_start __protected_start: /* Save the BIST value */ movl %eax, %ebp post_code(POST_ENTER_PROTECTED_MODE) movw $ROM_DATA_SEG, %ax movw %ax, %ds movw %ax, %es movw %ax, %ss movw %ax, %fs movw %ax, %gs /* Restore the BIST value to %eax */ movl %ebp, %eax