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 */
fpu_enable(void)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 */
fpu_disable(void)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 */
fpu_is_enabled(void)89 __always_inline static bool fpu_is_enabled(void)
90 {
91 return (REG_CPACR & (0xFu << 20));
92 }
93
94 #endif /* _FPU_H_INCLUDED_ */
95