xref: /optee_os/core/arch/arm/include/kernel/vfp.h (revision 1bb929836182ecb96d2d9d268daa807c67596396)
1 /* SPDX-License-Identifier: BSD-2-Clause */
2 /*
3  * Copyright (c) 2015, Linaro Limited
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions are met:
8  *
9  * 1. Redistributions of source code must retain the above copyright notice,
10  * this list of conditions and the following disclaimer.
11  *
12  * 2. Redistributions in binary form must reproduce the above copyright notice,
13  * this list of conditions and the following disclaimer in the documentation
14  * and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #ifndef KERNEL_VFP_H
30 #define KERNEL_VFP_H
31 
32 #include <types_ext.h>
33 #include <compiler.h>
34 
35 #ifdef ARM32
36 /*
37  * Advanced SIMD/floating point state on ARMv7-A or ARMv8-A AArch32 has:
38  * - 32 64-bit data registers
39  * - FPSCR (32 bits)
40  * - FPEXC (32 bits)
41  */
42 
43 #define VFP_NUM_REGS	32
44 
45 struct vfp_reg {
46 	uint64_t v;
47 };
48 
49 struct vfp_state {
50 	uint32_t fpexc;
51 	uint32_t fpscr;
52 	struct vfp_reg reg[VFP_NUM_REGS];
53 };
54 #endif
55 
56 #ifdef ARM64
57 /*
58  * Advanced SIMD/floating point state on ARMv8-A AArch64 has:
59  * - 32 128-bit data registers
60  * - FPSR (32 bits)
61  * - FPCR (32 bits)
62  * - CPACR_EL1.FPEN (2 bits)
63  */
64 
65 #define VFP_NUM_REGS	32
66 
67 struct vfp_reg {
68 	uint8_t v[16];
69 } __aligned(16);
70 
71 struct vfp_state {
72 	struct vfp_reg reg[VFP_NUM_REGS];
73 	uint32_t fpsr;
74 	uint32_t fpcr;
75 	uint32_t cpacr_el1;
76 	bool force_save; /* Save to reg even if VFP was not enabled */
77 };
78 #endif
79 
80 #ifdef CFG_WITH_VFP
81 /* vfp_is_enabled() - Returns true if VFP is enabled */
82 bool vfp_is_enabled(void);
83 
84 /* vfp_enable() - Enables vfp */
85 void vfp_enable(void);
86 
87 /* vfp_disable() - Disables vfp */
88 void vfp_disable(void);
89 #else
90 static inline bool vfp_is_enabled(void)
91 {
92 	return false;
93 }
94 
95 static inline void vfp_enable(void)
96 {
97 }
98 
99 static inline void vfp_disable(void)
100 {
101 }
102 #endif
103 
104 /*
105  * vfp_lazy_save_state_init() - Saves VFP enable status and disables VFP
106  * @state:	VFP state structure to initialize
107  */
108 void vfp_lazy_save_state_init(struct vfp_state *state);
109 
110 /*
111  * vfp_lazy_save_state_final() - Saves rest of VFP state
112  * @state:	VFP state to save to
113  *
114  * If VFP was enabled when vfp_lazy_save_state_init() was called: save rest
115  * of state and disable VFP. Otherwise, do nothing.
116  */
117 void vfp_lazy_save_state_final(struct vfp_state *state);
118 
119 /*
120  * vfp_lazy_restore_state() - Lazy restore VFP state
121  * @state:		VFP state to restore
122  *
123  * Restores VFP enable status and also restores rest of VFP state if
124  * vfp_lazy_save_state_final() was called on this state.
125  */
126 void vfp_lazy_restore_state(struct vfp_state *state, bool full_state);
127 
128 #endif /*KERNEL_VFP_H*/
129