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/*
* Memory Setup stuff - taken from blob memsetup.S
*
* Copyright (C) 1999 2000 2001 Erik Mouw (J.A.K.Mouw@its.tudelft.nl) and
* Jan-Derk Bakker (J.D.Bakker@its.tudelft.nl)
* 2003-2004 (c) MontaVista Software, Inc.
*
* 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"
.globl lowlevel_init
lowlevel_init:
/* The ADS GC+ for Linux Boot Rom Ver. 1.73 does memory init for us.
* However the darn thing leaves the MMU enabled before handing control
* over to us. So we need to disable the MMU and we use lowlevel_init
* to do it.
*/
@ The following code segment was borrowed with gratitude from:
@ linux-2.4.19-rmk7/arch/arm/boot/compressed/head-sa1100.S
@ Data cache might be active.
@ Be sure to flush kernel binary out of the cache,
@ whatever state it is, before it is turned off.
@ This is done by fetching through currently executed
@ memory to be sure we hit the same cache.
bic r2, pc, #0x1f
add r3, r2, #0x4000 @ 16 kb is quite enough...
1: ldr r0, [r2], #32
teq r2, r3
bne 1b
mcr p15, 0, r0, c7, c10, 4 @ drain WB
mcr p15, 0, r0, c7, c7, 0 @ flush I & D caches
@ disabling MMU and caches
mrc p15, 0, r0, c1, c0, 0 @ read control reg
bic r0, r0, #0x0d @ clear WB, DC, MMU
bic r0, r0, #0x1000 @ clear Icache
mcr p15, 0, r0, c1, c0, 0
nop
nop
nop
nop
nop
b 2f
2:
nop
nop
nop
nop
nop
mov pc, lr
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