u-boot/arch/arm/cpu/arm926ejs/mxs/start.S
Albert ARIBAUD b60eff31f3 arm: remove unneeded symbol offsets and _TEXT_BASE
Remove the last uses of symbol offsets in ARM U-Boot.
Remove some needless uses of _TEXT_BASE.
Remove all _TEXT_BASE definitions.

Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
2014-02-26 21:18:12 +01:00

185 lines
4.4 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 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>
#include <version.h>
/*
*************************************************************************
*
* Jump vector table as in table 3.1 in [1]
*
*************************************************************************
*/
.globl _start
_start:
b reset
b undefined_instruction
b software_interrupt
b prefetch_abort
b data_abort
b not_used
b irq
b fiq
/*
* Vector table, located at address 0x20.
* This table allows the code running AFTER SPL, the U-Boot, to install it's
* interrupt handlers here. The problem is that the U-Boot is loaded into RAM,
* including it's interrupt vectoring table and the table at 0x0 is still the
* SPLs. So if interrupt happens in U-Boot, the SPLs interrupt vectoring table
* is still used.
*/
_vt_reset:
.word _reset
_vt_undefined_instruction:
.word _hang
_vt_software_interrupt:
.word _hang
_vt_prefetch_abort:
.word _hang
_vt_data_abort:
.word _hang
_vt_not_used:
.word _reset
_vt_irq:
.word _hang
_vt_fiq:
.word _hang
reset:
ldr pc, _vt_reset
undefined_instruction:
ldr pc, _vt_undefined_instruction
software_interrupt:
ldr pc, _vt_software_interrupt
prefetch_abort:
ldr pc, _vt_prefetch_abort
data_abort:
ldr pc, _vt_data_abort
not_used:
ldr pc, _vt_not_used
irq:
ldr pc, _vt_irq
fiq:
ldr pc, _vt_fiq
.balignl 16,0xdeadbeef
/*
*************************************************************************
*
* 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
*
*************************************************************************
*/
#ifdef CONFIG_USE_IRQ
/* IRQ stack memory (calculated at run-time) */
.globl IRQ_STACK_START
IRQ_STACK_START:
.word 0x0badc0de
/* IRQ stack memory (calculated at run-time) */
.globl FIQ_STACK_START
FIQ_STACK_START:
.word 0x0badc0de
#endif
/* IRQ stack memory (calculated at run-time) + 8 bytes */
.globl IRQ_STACK_START_IN
IRQ_STACK_START_IN:
.word 0x0badc0de
/*
* the actual reset code
*/
_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
_hang:
1:
bl 1b /* hang and never return */