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-rw-r--r--arch/i386/cpu/start.S135
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diff --git a/arch/i386/cpu/start.S b/arch/i386/cpu/start.S
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+/*
+ * U-boot - i386 Startup Code
+ *
+ * Copyright (c) 2002 Omicron Ceti AB, Daniel Engström <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_asm
+.progress0:
+
+ /* size memory */
+ mov $mem_init_ret, %ebp
+ jmp mem_init
+mem_init_ret:
+
+ /* Check we have enough memory for stack */
+ movl $CONFIG_SYS_STACK_SIZE, %ecx
+ cmpl %ecx, %eax
+ jae mem_ok
+
+ /* indicate (lack of) progress */
+ movw $0x81, %ax
+ movl $.progress0a, %ebp
+ jmp show_boot_progress_asm
+.progress0a:
+ jmp die
+mem_ok:
+ /* Set stack pointer to upper memory limit*/
+ movl %eax, %esp
+
+ /* indicate progress */
+ movw $0x02, %ax
+ movl $.progress1, %ebp
+ jmp show_boot_progress_asm
+.progress1:
+
+ /* Test the stack */
+ 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_asm
+.progress1a:
+ jmp die
+
+
+stack_ok:
+ /* indicate progress */
+ movw $0x03, %ax
+ movl $.progress2, %ebp
+ jmp show_boot_progress_asm
+.progress2:
+
+ wbinvd
+
+ /* Get upper memory limit */
+ movl %esp, %ecx
+ subl $CONFIG_SYS_STACK_SIZE, %ecx
+
+ /* Create a Stack Frame */
+ pushl %ebp
+ movl %esp, %ebp
+
+ /* stack_limit parameter */
+ pushl %ecx
+ call board_init_f /* Enter, U-boot! */
+
+ /* indicate (lack of) progress */
+ movw $0x85, %ax
+ movl $.progress4a, %ebp
+ jmp show_boot_progress_asm
+.progress4a:
+
+die: hlt
+ jmp die
+ hlt