mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-12-12 14:23:00 +00:00
123 lines
3 KiB
ArmAsm
123 lines
3 KiB
ArmAsm
|
/*
|
||
|
|
* armboot - Startup Code for ARM926EJS CPU-core
|
||
|
|
*
|
||
|
|
* Copyright (c) 2003 Texas Instruments
|
||
|
|
*
|
||
|
|
* ----- Adapted for OMAP1610 OMAP730 from ARM925t code ------
|
||
|
|
*
|
||
|
|
* Copyright (c) 2001 Marius Gröger <mag@sysgo.de>
|
||
|
|
* Copyright (c) 2002 Alex Züpke <azu@sysgo.de>
|
||
|
|
* Copyright (c) 2002 Gary Jennejohn <garyj@denx.de>
|
||
|
|
* Copyright (c) 2003 Richard Woodruff <r-woodruff2@ti.com>
|
||
|
|
* Copyright (c) 2003 Kshitij <kshitij@ti.com>
|
||
|
|
*
|
||
|
|
* 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>
|
||
|
|
|
||
|
|
.globl _start
|
||
|
|
_start:
|
||
|
|
b reset
|
||
|
|
ldr pc, _undefined_instruction
|
||
|
|
ldr pc, _software_interrupt
|
||
|
|
ldr pc, _prefetch_abort
|
||
|
|
ldr pc, _data_abort
|
||
|
|
ldr pc, _not_used
|
||
|
|
ldr pc, _irq
|
||
|
|
ldr pc, _fiq
|
||
|
|
|
||
|
|
_undefined_instruction:
|
||
|
|
_software_interrupt:
|
||
|
|
_prefetch_abort:
|
||
|
|
_data_abort:
|
||
|
|
_not_used:
|
||
|
|
_irq:
|
||
|
|
_fiq:
|
||
|
|
.word infinite_loop
|
||
|
|
|
||
|
|
infinite_loop:
|
||
|
|
b infinite_loop
|
||
|
|
|
||
|
|
/*
|
||
|
|
*************************************************************************
|
||
|
|
*
|
||
|
|
* Startup Code (reset vector)
|
||
|
|
*
|
||
|
|
* Below are the critical initializations already taken place in BootROM.
|
||
|
|
* So, these are not taken care in Xloader
|
||
|
|
* 1. Relocation to RAM
|
||
|
|
* 2. Initializing stacks
|
||
|
|
*
|
||
|
|
*************************************************************************
|
||
|
|
*/
|
||
|
|
|
||
|
|
/*
|
||
|
|
* the actual reset code
|
||
|
|
*/
|
||
|
|
|
||
|
|
reset:
|
||
|
|
/*
|
||
|
|
* Xloader has to return back to BootROM in a few cases.
|
||
|
|
* eg. Ethernet boot, UART boot, USB boot
|
||
|
|
* Saving registers for returning back
|
||
|
|
*/
|
||
|
|
stmdb sp!, {r0-r12,r14}
|
||
|
|
bl cpu_init_crit
|
||
|
|
/*
|
||
|
|
* Clearing bss area is not done in Xloader.
|
||
|
|
* BSS area lies in the DDR location which is not yet initialized
|
||
|
|
* bss is assumed to be uninitialized.
|
||
|
|
*/
|
||
|
|
bl spl_boot
|
||
|
|
ldmia sp!, {r0-r12,pc}
|
||
|
|
|
||
|
|
/*
|
||
|
|
*************************************************************************
|
||
|
|
*
|
||
|
|
* CPU_init_critical registers
|
||
|
|
*
|
||
|
|
* setup important registers
|
||
|
|
* setup memory timing
|
||
|
|
*
|
||
|
|
*************************************************************************
|
||
|
|
*/
|
||
|
|
cpu_init_crit:
|
||
|
|
/*
|
||
|
|
* flush v4 I/D caches
|
||
|
|
*/
|
||
|
|
mov r0, #0
|
||
|
|
mcr p15, 0, r0, c7, c7, 0 /* flush v3/v4 cache */
|
||
|
|
mcr p15, 0, r0, c8, c7, 0 /* flush v4 TLB */
|
||
|
|
|
||
|
|
/*
|
||
|
|
* enable instruction cache
|
||
|
|
*/
|
||
|
|
mrc p15, 0, r0, c1, c0, 0
|
||
|
|
orr r0, r0, #0x00001000 /* set bit 12 (I) I-Cache */
|
||
|
|
mcr p15, 0, r0, c1, c0, 0
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Go setup Memory and board specific bits prior to relocation.
|
||
|
|
*/
|
||
|
|
stmdb sp!, {lr}
|
||
|
|
bl lowlevel_init /* go setup pll,mux,memory */
|
||
|
|
ldmia sp!, {pc}
|