/* * U-boot - i386 Startup Code * * Copyright (c) 2002 Omicron Ceti AB, Daniel Engstr�m <denaiel@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> .section .text .code32 .globl _start .type _start, @function .globl _i386boot_start _i386boot_start: _start: movl $0x18,%eax /* Load our segement registes, the * gdt have already been loaded by start16.S */ movw %ax,%fs movw %ax,%ds movw %ax,%gs movw %ax,%es movw %ax,%ss /* We call a few functions in the board support package * since we have no stack yet we'll have to use %ebp * to store the return address */ /* Early platform init (setup gpio, etc ) */ mov $early_board_init_ret, %ebp jmp early_board_init early_board_init_ret: /* The __port80 entry-point should be usabe by now */ /* so we try to indicate progress */ movw $0x01, %ax movl $.progress0, %ebp jmp __show_boot_progress .progress0: /* size memory */ mov $mem_init_ret, %ebp jmp mem_init mem_init_ret: /* check ammount of configured memory * (we need atleast bss start+bss size+stack size) */ movl $_i386boot_bss_start, %ecx /* BSS start */ addl $_i386boot_bss_size, %ecx /* BSS size */ addl $CFG_STACK_SIZE, %ecx cmpl %ecx, %eax jae mem_ok /* indicate (lack of) progress */ movw $0x81, %ax movl $.progress0a, %ebp jmp __show_boot_progress .progress0a: jmp die mem_ok: /* indicate progress */ movw $0x02, %ax movl $.progress1, %ebp jmp __show_boot_progress .progress1: /* create a stack after the bss */ movl $_i386boot_bss_start, %eax addl $_i386boot_bss_size, %eax addl $CFG_STACK_SIZE, %eax movl %eax, %esp pushl $0 popl %eax cmpl $0, %eax jne no_stack push $0x55aa55aa popl %ebx cmpl $0x55aa55aa, %ebx je stack_ok no_stack: /* indicate (lack of) progress */ movw $0x82, %ax movl $.progress1a, %ebp jmp __show_boot_progress .progress1a: jmp die stack_ok: /* indicate progress */ movw $0x03, %ax movl $.progress2, %ebp jmp __show_boot_progress .progress2: /* copy data section to ram, size must be 4-byte aligned */ movl $_i386boot_romdata_dest, %edi /* destination address */ movl $_i386boot_romdata_start, %esi /* source address */ movl $_i386boot_romdata_size, %ecx /* number of bytes to copy */ movl %ecx, %eax andl $3, %eax jnz data_fail shrl $2, %ecx /* copy 4 byte each time */ cld cmpl $0, %ecx je data_ok data_segment: movsl loop data_segment jmp data_ok data_fail: /* indicate (lack of) progress */ movw $0x83, %ax movl $.progress2a, %ebp jmp __show_boot_progress .progress2a: jmp die data_ok: /* indicate progress */ movw $0x04, %ax movl $.progress3, %ebp jmp __show_boot_progress .progress3: /* clear bss section in ram, size must be 4-byte aligned */ movl $_i386boot_bss_start, %eax /* BSS start */ movl $_i386boot_bss_size, %ecx /* BSS size */ movl %ecx, %eax andl $3, %eax jnz bss_fail shrl $2, %ecx /* clear 4 byte each time */ cld cmpl $0, %ecx je bss_ok bss: movl $0, (%edi) add $4, %edi loop bss jmp bss_ok bss_fail: /* indicate (lack of) progress */ movw $0x84, %ax movl $.progress3a, %ebp jmp __show_boot_progress .progress3a: jmp die bss_ok: wbinvd /* indicate progress */ movw $0x05, %ax movl $.progress4, %ebp jmp __show_boot_progress .progress4: call start_i386boot /* Enter, U-boot! */ /* indicate (lack of) progress */ movw $0x85, %ax movl $.progress4a, %ebp jmp __show_boot_progress .progress4a: die: hlt jmp die hlt