rt-thread-official/libcpu/arm/armv6/vfp.c

39 lines
743 B
C

/*
* Copyright (c) 2006-2018, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2014-11-07 weety first version
*/
#include <rthw.h>
#include <rtthread.h>
#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