/* * File : vfp.c * This file is part of RT-Thread RTOS * COPYRIGHT (C) 2006, RT-Thread Develop Team * * 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., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. * * Change Logs: * Date Author Notes * 2014-11-07 weety first version */ #include #include #include "vfp.h" #ifdef RT_USING_VFP void vfp_init(void) { int ret = 0; unsigned int value; asm volatile ("mrc p15, 0, %0, c1, c0, 2" :"=r"(value) :); value |= 0xf00000;/*enable CP10, CP11 user access*/ asm volatile("mcr p15, 0, %0, c1, c0, 2" : :"r"(value)); asm volatile("fmrx %0, fpexc" :"=r"(value)); value |=(1<<30); asm volatile("fmxr fpexc, %0" : :"r"(value)); } #endif