diff options
Diffstat (limited to 'arch/arm/cpu/arm926ejs/spear/start.S')
-rw-r--r-- | arch/arm/cpu/arm926ejs/spear/start.S | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/arch/arm/cpu/arm926ejs/spear/start.S b/arch/arm/cpu/arm926ejs/spear/start.S new file mode 100644 index 0000000..a103c0f --- /dev/null +++ b/arch/arm/cpu/arm926ejs/spear/start.S @@ -0,0 +1,122 @@ +/* + * 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} |