197 lines
4.2 KiB
ArmAsm
197 lines
4.2 KiB
ArmAsm
|
/*
|
|||
|
* U-boot - i386 Startup Code
|
|||
|
*
|
|||
|
* Copyright (c) 2002 Omicron Ceti AB, Daniel Engstr<EFBFBD>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
|