1 /** 2 * \file 3 * 4 * \brief FPU support for SAM. 5 * 6 * Copyright (c) 2014-2015 Atmel Corporation. All rights reserved. 7 * 8 * \asf_license_start 9 * 10 * \page License 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions are met: 14 * 15 * 1. Redistributions of source code must retain the above copyright notice, 16 * this list of conditions and the following disclaimer. 17 * 18 * 2. Redistributions in binary form must reproduce the above copyright notice, 19 * this list of conditions and the following disclaimer in the documentation 20 * and/or other materials provided with the distribution. 21 * 22 * 3. The name of Atmel may not be used to endorse or promote products derived 23 * from this software without specific prior written permission. 24 * 25 * 4. This software may only be redistributed and used in connection with an 26 * Atmel microcontroller product. 27 * 28 * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED 29 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 30 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE 31 * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR 32 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 36 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 37 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 38 * POSSIBILITY OF SUCH DAMAGE. 39 * 40 * \asf_license_stop 41 * 42 */ 43 /* 44 * Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a> 45 */ 46 47 #ifndef _FPU_H_INCLUDED_ 48 #define _FPU_H_INCLUDED_ 49 50 #include <compiler.h> 51 52 /** Address for ARM CPACR */ 53 #define ADDR_CPACR 0xE000ED88 54 55 /** CPACR Register */ 56 #define REG_CPACR (*((volatile uint32_t *)ADDR_CPACR)) 57 58 /** 59 * \brief Enable FPU 60 */ 61 __always_inline static void fpu_enable(void) 62 { 63 irqflags_t flags; 64 flags = cpu_irq_save(); 65 REG_CPACR |= (0xFu << 20); 66 __DSB(); 67 __ISB(); 68 cpu_irq_restore(flags); 69 } 70 71 /** 72 * \brief Disable FPU 73 */ 74 __always_inline static void fpu_disable(void) 75 { 76 irqflags_t flags; 77 flags = cpu_irq_save(); 78 REG_CPACR &= ~(0xFu << 20); 79 __DSB(); 80 __ISB(); 81 cpu_irq_restore(flags); 82 } 83 84 /** 85 * \brief Check if FPU is enabled 86 * 87 * \return Return ture if FPU is enabled, otherwise return false. 88 */ 89 __always_inline static bool fpu_is_enabled(void) 90 { 91 return (REG_CPACR & (0xFu << 20)); 92 } 93 94 #endif /* _FPU_H_INCLUDED_ */ 95