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/*
* armboot - Startup Code for ARM926EJS CPU-core
*
* Copyright (c) 2003 Texas Instruments
*
* ----- Adapted for OMAP1610 OMAP730 from ARM925t code ------
*
* Copyright (c) 2001 Marius Groger <mag@sysgo.de>
* Copyright (c) 2002 Alex Zupke <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>
* Copyright (c) 2010 Albert Aribaud <albert.u.boot@aribaud.net>
*
* Change to support call back into iMX28 bootrom
* Copyright (c) 2011 Marek Vasut <marek.vasut@gmail.com>
* on behalf of DENX Software Engineering GmbH
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <asm-offsets.h>
#include <config.h>
#include <common.h>
/*
*************************************************************************
*
* Startup Code (reset vector)
*
* do important init only if we don't start from memory!
* setup Memory and board specific bits prior to relocation.
* relocate armboot to ram
* setup stack
*
*************************************************************************
*/
.globl reset
reset:
/*
* If the CPU is configured in "Wait JTAG connection mode", the stack
* pointer is not configured and is zero. This will cause crash when
* trying to push data onto stack right below here. Load the SP and make
* it point to the end of OCRAM if the SP is zero.
*/
cmp sp, #0x00000000
ldreq sp, =CONFIG_SYS_INIT_SP_ADDR
/*
* Store all registers on old stack pointer, this will allow us later to
* return to the BootROM and let the BootROM load U-Boot into RAM.
*
* WARNING: Register r0 and r1 are used by the BootROM to pass data
* to the called code. Register r0 will contain arbitrary
* data that are set in the BootStream. In case this code
* was started with CALL instruction, register r1 will contain
* pointer to the return value this function can then set.
* The code below MUST NOT CHANGE register r0 and r1 !
*/
push {r0-r12,r14}
/* Save control register c1 */
mrc p15, 0, r2, c1, c0, 0
push {r2}
/* Set the cpu to SVC32 mode and store old CPSR register content. */
mrs r2, cpsr
push {r2}
bic r2, r2, #0x1f
orr r2, r2, #0xd3
msr cpsr, r2
bl board_init_ll
/* Restore BootROM's CPU mode (especially FIQ). */
pop {r2}
msr cpsr,r2
/*
* Restore c1 register. Especially set exception vector location
* back to BootROM space which is required by bootrom for USB boot.
*/
pop {r2}
mcr p15, 0, r2, c1, c0, 0
pop {r0-r12,r14}
/*
* In case this code was started by the CALL instruction, the register
* r0 is examined by the BootROM after this code returns. The value in
* r0 must be set to 0 to indicate successful return.
*/
mov r0, #0
bx lr
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