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 * Copyright (c) 2010 Albert Aribaud <albert.u.boot@aribaud.net> 14 * 15 * SPDX-License-Identifier: GPL-2.0+ 16 */ 17 18#include <asm-offsets.h> 19#include <config.h> 20 21/* 22 ************************************************************************* 23 * 24 * Startup Code (reset vector) 25 * 26 * do important init only if we don't start from memory! 27 * setup Memory and board specific bits prior to relocation. 28 * relocate armboot to ram 29 * setup stack 30 * 31 ************************************************************************* 32 */ 33 34 .globl reset 35 36reset: 37 /* 38 * set the cpu to SVC32 mode 39 */ 40 mrs r0,cpsr 41 bic r0,r0,#0x1f 42 orr r0,r0,#0xd3 43 msr cpsr,r0 44 45 /* 46 * we do sys-critical inits only at reboot, 47 * not when booting from ram! 48 */ 49#ifndef CONFIG_SKIP_LOWLEVEL_INIT 50 bl cpu_init_crit 51#endif 52 53 bl _main 54 55/*------------------------------------------------------------------------------*/ 56 57 .globl c_runtime_cpu_setup 58c_runtime_cpu_setup: 59 60 mov pc, lr 61 62/* 63 ************************************************************************* 64 * 65 * CPU_init_critical registers 66 * 67 * setup important registers 68 * setup memory timing 69 * 70 ************************************************************************* 71 */ 72 73 74#ifndef CONFIG_SKIP_LOWLEVEL_INIT 75cpu_init_crit: 76 /* 77 * flush v4 I/D caches 78 */ 79 mov r0, #0 80 mcr p15, 0, r0, c7, c5, 0 /* flush v4 I-cache */ 81 mcr p15, 0, r0, c7, c6, 0 /* flush v4 D-cache */ 82 83 /* 84 * disable MMU stuff and caches 85 */ 86 mrc p15, 0, r0, c1, c0, 0 87 bic r0, r0, #0x00002300 /* clear bits 13, 9:8 (--V- --RS) */ 88 bic r0, r0, #0x00000087 /* clear bits 7, 2:0 (B--- -CAM) */ 89 orr r0, r0, #0x00000002 /* set bit 1 (A) Align */ 90 orr r0, r0, #0x00001000 /* set bit 12 (I) I-Cache */ 91 mcr p15, 0, r0, c1, c0, 0 92 93 /* 94 * Go setup Memory and board specific bits prior to relocation. 95 */ 96 mov ip, lr /* perserve link reg across call */ 97 bl lowlevel_init /* go setup memory */ 98 mov lr, ip /* restore link */ 99 mov pc, lr /* back to my caller */ 100#endif 101