1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 2012 ARM Ltd.
4 */
5#ifndef __ASM_FP_H
6#define __ASM_FP_H
7
8#include <asm/errno.h>
9#include <asm/ptrace.h>
10#include <asm/processor.h>
11#include <asm/sigcontext.h>
12#include <asm/sysreg.h>
13
14#ifndef __ASSEMBLY__
15
16#include <linux/bitmap.h>
17#include <linux/build_bug.h>
18#include <linux/bug.h>
19#include <linux/cache.h>
20#include <linux/init.h>
21#include <linux/stddef.h>
22#include <linux/types.h>
23
24#ifdef CONFIG_COMPAT
25/* Masks for extracting the FPSR and FPCR from the FPSCR */
26#define VFP_FPSCR_STAT_MASK	0xf800009f
27#define VFP_FPSCR_CTRL_MASK	0x07f79f00
28/*
29 * The VFP state has 32x64-bit registers and a single 32-bit
30 * control/status register.
31 */
32#define VFP_STATE_SIZE		((32 * 8) + 4)
33#endif
34
35struct task_struct;
36
37extern void fpsimd_save_state(struct user_fpsimd_state *state);
38extern void fpsimd_load_state(struct user_fpsimd_state *state);
39
40extern void fpsimd_thread_switch(struct task_struct *next);
41extern void fpsimd_flush_thread(void);
42
43extern void fpsimd_signal_preserve_current_state(void);
44extern void fpsimd_preserve_current_state(void);
45extern void fpsimd_restore_current_state(void);
46extern void fpsimd_update_current_state(struct user_fpsimd_state const *state);
47
48extern void fpsimd_bind_task_to_cpu(void);
49extern void fpsimd_bind_state_to_cpu(struct user_fpsimd_state *state,
50				     void *sve_state, unsigned int sve_vl);
51
52extern void fpsimd_flush_task_state(struct task_struct *target);
53extern void fpsimd_save_and_flush_cpu_state(void);
54
55/* Maximum VL that SVE VL-agnostic software can transparently support */
56#define SVE_VL_ARCH_MAX 0x100
57
58/* Offset of FFR in the SVE register dump */
59static inline size_t sve_ffr_offset(int vl)
60{
61	return SVE_SIG_FFR_OFFSET(sve_vq_from_vl(vl)) - SVE_SIG_REGS_OFFSET;
62}
63
64static inline void *sve_pffr(struct thread_struct *thread)
65{
66	return (char *)thread->sve_state + sve_ffr_offset(thread->sve_vl);
67}
68
69extern void sve_save_state(void *state, u32 *pfpsr);
70extern void sve_load_state(void const *state, u32 const *pfpsr,
71			   unsigned long vq_minus_1);
72extern void sve_flush_live(void);
73extern void sve_load_from_fpsimd_state(struct user_fpsimd_state const *state,
74				       unsigned long vq_minus_1);
75extern unsigned int sve_get_vl(void);
76
77struct arm64_cpu_capabilities;
78extern void sve_kernel_enable(const struct arm64_cpu_capabilities *__unused);
79
80extern u64 read_zcr_features(void);
81
82extern int __ro_after_init sve_max_vl;
83extern int __ro_after_init sve_max_virtualisable_vl;
84extern __ro_after_init DECLARE_BITMAP(sve_vq_map, SVE_VQ_MAX);
85
86/*
87 * Helpers to translate bit indices in sve_vq_map to VQ values (and
88 * vice versa).  This allows find_next_bit() to be used to find the
89 * _maximum_ VQ not exceeding a certain value.
90 */
91static inline unsigned int __vq_to_bit(unsigned int vq)
92{
93	return SVE_VQ_MAX - vq;
94}
95
96static inline unsigned int __bit_to_vq(unsigned int bit)
97{
98	return SVE_VQ_MAX - bit;
99}
100
101/* Ensure vq >= SVE_VQ_MIN && vq <= SVE_VQ_MAX before calling this function */
102static inline bool sve_vq_available(unsigned int vq)
103{
104	return test_bit(__vq_to_bit(vq), sve_vq_map);
105}
106
107#ifdef CONFIG_ARM64_SVE
108
109extern size_t sve_state_size(struct task_struct const *task);
110
111extern void sve_alloc(struct task_struct *task);
112extern void fpsimd_release_task(struct task_struct *task);
113extern void fpsimd_sync_to_sve(struct task_struct *task);
114extern void sve_sync_to_fpsimd(struct task_struct *task);
115extern void sve_sync_from_fpsimd_zeropad(struct task_struct *task);
116
117extern int sve_set_vector_length(struct task_struct *task,
118				 unsigned long vl, unsigned long flags);
119
120extern int sve_set_current_vl(unsigned long arg);
121extern int sve_get_current_vl(void);
122
123static inline void sve_user_disable(void)
124{
125	sysreg_clear_set(cpacr_el1, CPACR_EL1_ZEN_EL0EN, 0);
126}
127
128static inline void sve_user_enable(void)
129{
130	sysreg_clear_set(cpacr_el1, 0, CPACR_EL1_ZEN_EL0EN);
131}
132
133/*
134 * Probing and setup functions.
135 * Calls to these functions must be serialised with one another.
136 */
137extern void __init sve_init_vq_map(void);
138extern void sve_update_vq_map(void);
139extern int sve_verify_vq_map(void);
140extern void __init sve_setup(void);
141
142#else /* ! CONFIG_ARM64_SVE */
143
144static inline void sve_alloc(struct task_struct *task) { }
145static inline void fpsimd_release_task(struct task_struct *task) { }
146static inline void sve_sync_to_fpsimd(struct task_struct *task) { }
147static inline void sve_sync_from_fpsimd_zeropad(struct task_struct *task) { }
148
149static inline int sve_set_current_vl(unsigned long arg)
150{
151	return -EINVAL;
152}
153
154static inline int sve_get_current_vl(void)
155{
156	return -EINVAL;
157}
158
159static inline void sve_user_disable(void) { BUILD_BUG(); }
160static inline void sve_user_enable(void) { BUILD_BUG(); }
161
162static inline void sve_init_vq_map(void) { }
163static inline void sve_update_vq_map(void) { }
164static inline int sve_verify_vq_map(void) { return 0; }
165static inline void sve_setup(void) { }
166
167#endif /* ! CONFIG_ARM64_SVE */
168
169/* For use by EFI runtime services calls only */
170extern void __efi_fpsimd_begin(void);
171extern void __efi_fpsimd_end(void);
172
173#endif
174
175#endif
176