| /* |
| * U-boot - x86 Startup Code |
| * |
| * (C) Copyright 2008-2011 |
| * Graeme Russ, <graeme.russ@gmail.com> |
| * |
| * (C) Copyright 2002 |
| * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se> |
| * |
| * See file CREDITS for list of people who contributed to this |
| * project. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License as |
| * published by the Free Software Foundation; either version 2 of |
| * the License, or (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, |
| * MA 02111-1307 USA |
| */ |
| |
| #include <config.h> |
| #include <version.h> |
| #include <asm/global_data.h> |
| #include <asm/processor-flags.h> |
| |
| .section .text |
| .code32 |
| .globl _start |
| .type _start, @function |
| .globl _x86boot_start |
| _x86boot_start: |
| /* |
| * This is the fail safe 32-bit bootstrap entry point. The |
| * following code is not executed from a cold-reset (actually, a |
| * lot of it is, but from real-mode after cold reset. It is |
| * repeated here to put the board into a state as close to cold |
| * reset as necessary) |
| */ |
| cli |
| cld |
| |
| /* Turn of cache (this might require a 486-class CPU) */ |
| movl %cr0, %eax |
| orl $(X86_CR0_NW | X86_CR0_CD), %eax |
| movl %eax, %cr0 |
| wbinvd |
| |
| /* Tell 32-bit code it is being entered from an in-RAM copy */ |
| movw $GD_FLG_WARM_BOOT, %bx |
| _start: |
| /* This is the 32-bit cold-reset entry point */ |
| |
| /* Load the segement registes to match the gdt loaded in start16.S */ |
| movl $0x18, %eax |
| movw %ax, %fs |
| movw %ax, %ds |
| movw %ax, %gs |
| movw %ax, %es |
| movw %ax, %ss |
| |
| /* Clear the interupt vectors */ |
| lidt blank_idt_ptr |
| |
| /* Early platform init (setup gpio, etc ) */ |
| jmp early_board_init |
| .globl early_board_init_ret |
| early_board_init_ret: |
| |
| /* Initialise Cache-As-RAM */ |
| jmp car_init |
| .globl car_init_ret |
| car_init_ret: |
| /* |
| * We now have CONFIG_SYS_CAR_SIZE bytes of Cache-As-RAM (or SRAM, |
| * or fully initialised SDRAM - we really don't care which) |
| * starting at CONFIG_SYS_CAR_ADDR to be used as a temporary stack |
| */ |
| movl $CONFIG_SYS_INIT_SP_ADDR, %esp |
| |
| /* Set parameter to board_init_f() to boot flags */ |
| xorl %eax, %eax |
| movw %bx, %ax |
| |
| /* Enter, U-boot! */ |
| call board_init_f |
| |
| /* indicate (lack of) progress */ |
| movw $0x85, %ax |
| jmp die |
| |
| .globl relocate_code |
| .type relocate_code, @function |
| relocate_code: |
| /* |
| * SDRAM has been initialised, U-Boot code has been copied into |
| * RAM, BSS has been cleared and relocation adjustments have been |
| * made. It is now time to jump into the in-RAM copy of U-Boot |
| * |
| * %eax = Address of top of stack |
| * %edx = Address of Global Data |
| * %ecx = Base address of in-RAM copy of U-Boot |
| */ |
| |
| /* Setup stack in RAM */ |
| movl %eax, %esp |
| |
| /* Setup call address of in-RAM copy of board_init_r() */ |
| movl $board_init_r, %ebp |
| addl (GD_RELOC_OFF * 4)(%edx), %ebp |
| |
| /* Setup parameters to board_init_r() */ |
| movl %edx, %eax |
| movl %ecx, %edx |
| |
| /* Jump to in-RAM copy of board_init_r() */ |
| call *%ebp |
| |
| die: hlt |
| jmp die |
| hlt |
| |
| blank_idt_ptr: |
| .word 0 /* limit */ |
| .long 0 /* base */ |