1/* SPDX-License-Identifier: GPL-2.0+ */ 2/* 3 * armboot - Startup Code for ARM926EJS CPU-core 4 * 5 * Copyright (c) 2003 Texas Instruments 6 * 7 * ----- Adapted for OMAP1610 OMAP730 from ARM925t code ------ 8 * 9 * Copyright (c) 2001 Marius Gröger <mag@sysgo.de> 10 * Copyright (c) 2002 Alex Züpke <azu@sysgo.de> 11 * Copyright (c) 2002 Gary Jennejohn <garyj@denx.de> 12 * Copyright (c) 2003 Richard Woodruff <r-woodruff2@ti.com> 13 * Copyright (c) 2003 Kshitij <kshitij@ti.com> 14 * Copyright (c) 2010 Albert Aribaud <albert.u.boot@aribaud.net> 15 */ 16 17#include <asm-offsets.h> 18#include <config.h> 19 20/* 21 ************************************************************************* 22 * 23 * Startup Code (reset vector) 24 * 25 * do important init only if we don't start from memory! 26 * setup Memory and board specific bits prior to relocation. 27 * relocate armboot to ram 28 * setup stack 29 * 30 ************************************************************************* 31 */ 32 33 .globl reset 34 35reset: 36 /* 37 * set the cpu to SVC32 mode 38 */ 39 mrs r0,cpsr 40 bic r0,r0,#0x1f 41 orr r0,r0,#0xd3 42 msr cpsr,r0 43 44 /* 45 * we do sys-critical inits only at reboot, 46 * not when booting from ram! 47 */ 48#ifndef CONFIG_SKIP_LOWLEVEL_INIT 49 bl cpu_init_crit 50#endif 51 52 bl _main 53 54/*------------------------------------------------------------------------------*/ 55 56 .globl c_runtime_cpu_setup 57c_runtime_cpu_setup: 58 59 mov pc, lr 60 61/* 62 ************************************************************************* 63 * 64 * CPU_init_critical registers 65 * 66 * setup important registers 67 * setup memory timing 68 * 69 ************************************************************************* 70 */ 71 72 73#ifndef CONFIG_SKIP_LOWLEVEL_INIT 74cpu_init_crit: 75 /* 76 * flush v4 I/D caches 77 */ 78 mov r0, #0 79 mcr p15, 0, r0, c7, c5, 0 /* flush v4 I-cache */ 80 mcr p15, 0, r0, c7, c6, 0 /* flush v4 D-cache */ 81 82 /* 83 * disable MMU stuff and caches 84 */ 85 mrc p15, 0, r0, c1, c0, 0 86 bic r0, r0, #0x00002300 /* clear bits 13, 9:8 (--V- --RS) */ 87 bic r0, r0, #0x00000087 /* clear bits 7, 2:0 (B--- -CAM) */ 88 orr r0, r0, #0x00000002 /* set bit 1 (A) Align */ 89 orr r0, r0, #0x00001000 /* set bit 12 (I) I-Cache */ 90 mcr p15, 0, r0, c1, c0, 0 91 92#ifndef CONFIG_SKIP_LOWLEVEL_INIT_ONLY 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#endif 100 mov pc, lr /* back to my caller */ 101#endif 102