* Graeme Russ, <graeme.russ@gmail.com>
*
* (C) Copyright 2002
- * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
+ * 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
+ * SPDX-License-Identifier: GPL-2.0+
*/
#include <config.h>
#include <version.h>
#include <asm/global_data.h>
+#include <asm/processor.h>
#include <asm/processor-flags.h>
+#include <generated/generic-asm-offsets.h>
.section .text
.code32
cli
cld
- /* Turn of cache (this might require a 486-class CPU) */
+ /* Turn off cache (this might require a 486-class CPU) */
movl %cr0, %eax
orl $(X86_CR0_NW | X86_CR0_CD), %eax
movl %eax, %cr0
/* Tell 32-bit code it is being entered from an in-RAM copy */
movw $GD_FLG_WARM_BOOT, %bx
+ jmp 1f
_start:
- /* This is the 32-bit cold-reset entry point */
+ /*
+ * This is the 32-bit cold-reset entry point. Initialize %bx to 0
+ * in case we're preceeded by some sort of boot stub.
+ */
+ movw $GD_FLG_COLD_BOOT, %bx
+1:
/* Load the segement registes to match the gdt loaded in start16.S */
- movl $0x18, %eax
+ movl $(X86_GDT_ENTRY_32BIT_DS * X86_GDT_ENTRY_SIZE), %eax
movw %ax, %fs
movw %ax, %ds
movw %ax, %gs
movw %ax, %es
movw %ax, %ss
- /* Clear the interupt vectors */
+ /* Clear the interrupt vectors */
lidt blank_idt_ptr
/* Early platform init (setup gpio, etc ) */
* 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
+
+ /* Stack grows down from top of CAR */
+ movl $(CONFIG_SYS_CAR_ADDR + CONFIG_SYS_CAR_SIZE), %esp
+
+ /* Reserve space on stack for global data */
+ subl $GENERATED_GBL_DATA_SIZE, %esp
+
+ /* Align global data to 16-byte boundary */
+ andl $0xfffffff0, %esp
+
+ /* Setup first parameter to setup_gdt */
+ movl %esp, %eax
+
+ /* Reserve space for global descriptor table */
+ subl $X86_GDT_SIZE, %esp
+
+ /* Align temporary global descriptor table to 16-byte boundary */
+ andl $0xfffffff0, %esp
+
+ /* Set second parameter to setup_gdt */
+ movl %esp, %edx
+
+ /* Setup global descriptor table so gd->xyz works */
+ call setup_gdt
/* Set parameter to board_init_f() to boot flags */
xorl %eax, %eax
movw $0x85, %ax
jmp die
-.globl relocate_code
-.type relocate_code, @function
-relocate_code:
+.globl board_init_f_r_trampoline
+.type board_init_f_r_trampoline, @function
+board_init_f_r_trampoline:
/*
* 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
+ * %eax = Address of top of new stack
*/
- /* Setup stack in RAM */
+ /* Stack grows down from top of SDRAM */
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
+ /* Reserve space on stack for global data */
+ subl $GENERATED_GBL_DATA_SIZE, %esp
+
+ /* Align global data to 16-byte boundary */
+ andl $0xfffffff0, %esp
+
+ /* Setup first parameter to memcpy (and setup_gdt) */
+ movl %esp, %eax
+
+ /* Setup second parameter to memcpy */
+ fs movl 0, %edx
+
+ /* Set third parameter to memcpy */
+ movl $GENERATED_GBL_DATA_SIZE, %ecx
+
+ /* Copy global data from CAR to SDRAM stack */
+ call memcpy
- /* Setup parameters to board_init_r() */
- movl %edx, %eax
- movl %ecx, %edx
+ /* Reserve space for global descriptor table */
+ subl $X86_GDT_SIZE, %esp
- /* Jump to in-RAM copy of board_init_r() */
- call *%ebp
+ /* Align global descriptor table to 16-byte boundary */
+ andl $0xfffffff0, %esp
-die: hlt
+ /* Set second parameter to setup_gdt */
+ movl %esp, %edx
+
+ /* Setup global descriptor table so gd->xyz works */
+ call setup_gdt
+
+ /* Re-enter U-Boot by calling board_init_f_r */
+ call board_init_f_r
+
+die:
+ hlt
jmp die
hlt
blank_idt_ptr:
.word 0 /* limit */
.long 0 /* base */
+
+ .p2align 2 /* force 4-byte alignment */
+
+multiboot_header:
+ /* magic */
+ .long 0x1BADB002
+ /* flags */
+ .long (1 << 16)
+ /* checksum */
+ .long -0x1BADB002 - (1 << 16)
+ /* header addr */
+ .long multiboot_header - _x86boot_start + CONFIG_SYS_TEXT_BASE
+ /* load addr */
+ .long CONFIG_SYS_TEXT_BASE
+ /* load end addr */
+ .long 0
+ /* bss end addr */
+ .long 0
+ /* entry addr */
+ .long CONFIG_SYS_TEXT_BASE
projects / karo-tx-uboot.git / blobdiff