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/*
* reset AT91SAM9G20 as per errata
*
* (C) BitBox Ltd 2010
*
* unless the SDRAM is cleanly shutdown before we hit the
* reset register it can be left driving the data bus and
* killing the chance of a subsequent boot from NAND
*
* 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.
*/
#include <linux/linkage.h>
#include <mach/hardware.h>
#include <mach/at91_ramc.h>
#include "at91_rstc.h"
.arm
.globl at91sam9_alt_restart
at91sam9_alt_restart: ldr r0, =at91_ramc_base @ preload constants
ldr r0, [r0]
ldr r4, =at91_rstc_base
ldr r1, [r4]
mov r2, #1
mov r3, #AT91_SDRAMC_LPCB_POWER_DOWN
ldr r4, =AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST
.balign 32 @ align to cache line
str r2, [r0, #AT91_SDRAMC_TR] @ disable SDRAM access
str r3, [r0, #AT91_SDRAMC_LPR] @ power down SDRAM
str r4, [r1, #AT91_RSTC_CR] @ reset processor
b .
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