1/* 2 * armboot - Startup Code for ARM926EJS CPU-core 3 * 4 * Copyright (c) 2003 Texas Instruments 5 * 6 * ----- Adapted for OMAP1610 OMAP730 from ARM925t code ------ 7 * 8 * Copyright (c) 2001 Marius Gröger <mag@sysgo.de> 9 * Copyright (c) 2002 Alex Züpke <azu@sysgo.de> 10 * Copyright (c) 2002 Gary Jennejohn <garyj@denx.de> 11 * Copyright (c) 2003 Richard Woodruff <r-woodruff2@ti.com> 12 * Copyright (c) 2003 Kshitij <kshitij@ti.com> 13 * 14 * See file CREDITS for list of people who contributed to this 15 * project. 16 * 17 * This program is free software; you can redistribute it and/or 18 * modify it under the terms of the GNU General Public License as 19 * published by the Free Software Foundation; either version 2 of 20 * the License, or (at your option) any later version. 21 * 22 * This program is distributed in the hope that it will be useful, 23 * but WITHOUT ANY WARRANTY; without even the implied warranty of 24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 25 * GNU General Public License for more details. 26 * 27 * You should have received a copy of the GNU General Public License 28 * along with this program; if not, write to the Free Software 29 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 30 * MA 02111-1307 USA 31 */ 32 33 34#include <config.h> 35 36.globl _start 37_start: 38 b reset 39 ldr pc, _undefined_instruction 40 ldr pc, _software_interrupt 41 ldr pc, _prefetch_abort 42 ldr pc, _data_abort 43 ldr pc, _not_used 44 ldr pc, _irq 45 ldr pc, _fiq 46 47_undefined_instruction: 48_software_interrupt: 49_prefetch_abort: 50_data_abort: 51_not_used: 52_irq: 53_fiq: 54 .word infinite_loop 55 56infinite_loop: 57 b infinite_loop 58 59/* 60 ************************************************************************* 61 * 62 * Startup Code (reset vector) 63 * 64 * Below are the critical initializations already taken place in BootROM. 65 * So, these are not taken care in Xloader 66 * 1. Relocation to RAM 67 * 2. Initializing stacks 68 * 69 ************************************************************************* 70 */ 71 72/* 73 * the actual reset code 74 */ 75 76reset: 77/* 78 * Xloader has to return back to BootROM in a few cases. 79 * eg. Ethernet boot, UART boot, USB boot 80 * Saving registers for returning back 81 */ 82 stmdb sp!, {r0-r12,r14} 83 bl cpu_init_crit 84/* 85 * Clearing bss area is not done in Xloader. 86 * BSS area lies in the DDR location which is not yet initialized 87 * bss is assumed to be uninitialized. 88 */ 89 bl spl_boot 90 ldmia sp!, {r0-r12,pc} 91 92/* 93 ************************************************************************* 94 * 95 * CPU_init_critical registers 96 * 97 * setup important registers 98 * setup memory timing 99 * 100 ************************************************************************* 101 */ 102cpu_init_crit: 103 /* 104 * flush v4 I/D caches 105 */ 106 mov r0, #0 107 mcr p15, 0, r0, c7, c7, 0 /* flush v3/v4 cache */ 108 mcr p15, 0, r0, c8, c7, 0 /* flush v4 TLB */ 109 110 /* 111 * enable instruction cache 112 */ 113 mrc p15, 0, r0, c1, c0, 0 114 orr r0, r0, #0x00001000 /* set bit 12 (I) I-Cache */ 115 mcr p15, 0, r0, c1, c0, 0 116 117 /* 118 * Go setup Memory and board specific bits prior to relocation. 119 */ 120 stmdb sp!, {lr} 121 bl lowlevel_init /* go setup pll,mux,memory */ 122 ldmia sp!, {pc} 123