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Linux kernel mirror (for testing)
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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(unsigned long vq_minus_1);
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);
76extern void sve_set_vq(unsigned long vq_minus_1);
77
78struct arm64_cpu_capabilities;
79extern void sve_kernel_enable(const struct arm64_cpu_capabilities *__unused);
80
81extern u64 read_zcr_features(void);
82
83extern int __ro_after_init sve_max_vl;
84extern int __ro_after_init sve_max_virtualisable_vl;
85extern __ro_after_init DECLARE_BITMAP(sve_vq_map, SVE_VQ_MAX);
86
87/*
88 * Helpers to translate bit indices in sve_vq_map to VQ values (and
89 * vice versa). This allows find_next_bit() to be used to find the
90 * _maximum_ VQ not exceeding a certain value.
91 */
92static inline unsigned int __vq_to_bit(unsigned int vq)
93{
94 return SVE_VQ_MAX - vq;
95}
96
97static inline unsigned int __bit_to_vq(unsigned int bit)
98{
99 return SVE_VQ_MAX - bit;
100}
101
102/* Ensure vq >= SVE_VQ_MIN && vq <= SVE_VQ_MAX before calling this function */
103static inline bool sve_vq_available(unsigned int vq)
104{
105 return test_bit(__vq_to_bit(vq), sve_vq_map);
106}
107
108#ifdef CONFIG_ARM64_SVE
109
110extern size_t sve_state_size(struct task_struct const *task);
111
112extern void sve_alloc(struct task_struct *task);
113extern void fpsimd_release_task(struct task_struct *task);
114extern void fpsimd_sync_to_sve(struct task_struct *task);
115extern void sve_sync_to_fpsimd(struct task_struct *task);
116extern void sve_sync_from_fpsimd_zeropad(struct task_struct *task);
117
118extern int sve_set_vector_length(struct task_struct *task,
119 unsigned long vl, unsigned long flags);
120
121extern int sve_set_current_vl(unsigned long arg);
122extern int sve_get_current_vl(void);
123
124static inline void sve_user_disable(void)
125{
126 sysreg_clear_set(cpacr_el1, CPACR_EL1_ZEN_EL0EN, 0);
127}
128
129static inline void sve_user_enable(void)
130{
131 sysreg_clear_set(cpacr_el1, 0, CPACR_EL1_ZEN_EL0EN);
132}
133
134#define sve_cond_update_zcr_vq(val, reg) \
135 do { \
136 u64 __zcr = read_sysreg_s((reg)); \
137 u64 __new = __zcr & ~ZCR_ELx_LEN_MASK; \
138 __new |= (val) & ZCR_ELx_LEN_MASK; \
139 if (__zcr != __new) \
140 write_sysreg_s(__new, (reg)); \
141 } while (0)
142
143/*
144 * Probing and setup functions.
145 * Calls to these functions must be serialised with one another.
146 */
147extern void __init sve_init_vq_map(void);
148extern void sve_update_vq_map(void);
149extern int sve_verify_vq_map(void);
150extern void __init sve_setup(void);
151
152#else /* ! CONFIG_ARM64_SVE */
153
154static inline void sve_alloc(struct task_struct *task) { }
155static inline void fpsimd_release_task(struct task_struct *task) { }
156static inline void sve_sync_to_fpsimd(struct task_struct *task) { }
157static inline void sve_sync_from_fpsimd_zeropad(struct task_struct *task) { }
158
159static inline int sve_set_current_vl(unsigned long arg)
160{
161 return -EINVAL;
162}
163
164static inline int sve_get_current_vl(void)
165{
166 return -EINVAL;
167}
168
169static inline void sve_user_disable(void) { BUILD_BUG(); }
170static inline void sve_user_enable(void) { BUILD_BUG(); }
171
172#define sve_cond_update_zcr_vq(val, reg) do { } while (0)
173
174static inline void sve_init_vq_map(void) { }
175static inline void sve_update_vq_map(void) { }
176static inline int sve_verify_vq_map(void) { return 0; }
177static inline void sve_setup(void) { }
178
179#endif /* ! CONFIG_ARM64_SVE */
180
181/* For use by EFI runtime services calls only */
182extern void __efi_fpsimd_begin(void);
183extern void __efi_fpsimd_end(void);
184
185#endif
186
187#endif