arch/arm64/include/asm/fpsimd.h

   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 #if defined(__KERNEL__) && defined(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
  35 struct task_struct;
  36
  37 extern void fpsimd_save_state(struct user_fpsimd_state *state);
  38 extern void fpsimd_load_state(struct user_fpsimd_state *state);
  39
  40 extern void fpsimd_thread_switch(struct task_struct *next);
  41 extern void fpsimd_flush_thread(void);
  42
  43 extern void fpsimd_signal_preserve_current_state(void);
  44 extern void fpsimd_preserve_current_state(void);
  45 extern void fpsimd_restore_current_state(void);
  46 extern void fpsimd_update_current_state(struct user_fpsimd_state const *state);
  47
  48 extern void fpsimd_bind_task_to_cpu(void);
  49 extern void fpsimd_bind_state_to_cpu(struct user_fpsimd_state *state,
  50                                      void *sve_state, unsigned int sve_vl);
  51
  52 extern void fpsimd_flush_task_state(struct task_struct *target);
  53 extern 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 */
  59 static 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
  64 static inline void *sve_pffr(struct thread_struct *thread)
  65 {
  66         return (char *)thread->sve_state + sve_ffr_offset(thread->sve_vl);
  67 }
  68
  69 extern void sve_save_state(void *state, u32 *pfpsr);
  70 extern void sve_load_state(void const *state, u32 const *pfpsr,
  71                            unsigned long vq_minus_1);
  72 extern unsigned int sve_get_vl(void);
  73
  74 struct arm64_cpu_capabilities;
  75 extern void sve_kernel_enable(const struct arm64_cpu_capabilities *__unused);
  76
  77 extern u64 read_zcr_features(void);
  78
  79 extern int __ro_after_init sve_max_vl;
  80 extern int __ro_after_init sve_max_virtualisable_vl;
  81 extern __ro_after_init DECLARE_BITMAP(sve_vq_map, SVE_VQ_MAX);
  82
  83 /*
  84  * Helpers to translate bit indices in sve_vq_map to VQ values (and
  85  * vice versa).  This allows find_next_bit() to be used to find the
  86  * _maximum_ VQ not exceeding a certain value.
  87  */
  88 static inline unsigned int __vq_to_bit(unsigned int vq)
  89 {
  90         return SVE_VQ_MAX - vq;
  91 }
  92
  93 static inline unsigned int __bit_to_vq(unsigned int bit)
  94 {
  95         return SVE_VQ_MAX - bit;
  96 }
  97
  98 /* Ensure vq >= SVE_VQ_MIN && vq <= SVE_VQ_MAX before calling this function */
  99 static inline bool sve_vq_available(unsigned int vq)
 100 {
 101         return test_bit(__vq_to_bit(vq), sve_vq_map);
 102 }
 103
 104 #ifdef CONFIG_ARM64_SVE
 105
 106 extern size_t sve_state_size(struct task_struct const *task);
 107
 108 extern void sve_alloc(struct task_struct *task);
 109 extern void fpsimd_release_task(struct task_struct *task);
 110 extern void fpsimd_sync_to_sve(struct task_struct *task);
 111 extern void sve_sync_to_fpsimd(struct task_struct *task);
 112 extern void sve_sync_from_fpsimd_zeropad(struct task_struct *task);
 113
 114 extern int sve_set_vector_length(struct task_struct *task,
 115                                  unsigned long vl, unsigned long flags);
 116
 117 extern int sve_set_current_vl(unsigned long arg);
 118 extern int sve_get_current_vl(void);
 119
 120 static inline void sve_user_disable(void)
 121 {
 122         sysreg_clear_set(cpacr_el1, CPACR_EL1_ZEN_EL0EN, 0);
 123 }
 124
 125 static inline void sve_user_enable(void)
 126 {
 127         sysreg_clear_set(cpacr_el1, 0, CPACR_EL1_ZEN_EL0EN);
 128 }
 129
 130 /*
 131  * Probing and setup functions.
 132  * Calls to these functions must be serialised with one another.
 133  */
 134 extern void __init sve_init_vq_map(void);
 135 extern void sve_update_vq_map(void);
 136 extern int sve_verify_vq_map(void);
 137 extern void __init sve_setup(void);
 138
 139 #else /* ! CONFIG_ARM64_SVE */
 140
 141 static inline void sve_alloc(struct task_struct *task) { }
 142 static inline void fpsimd_release_task(struct task_struct *task) { }
 143 static inline void sve_sync_to_fpsimd(struct task_struct *task) { }
 144 static inline void sve_sync_from_fpsimd_zeropad(struct task_struct *task) { }
 145
 146 static inline int sve_set_current_vl(unsigned long arg)
 147 {
 148         return -EINVAL;
 149 }
 150
 151 static inline int sve_get_current_vl(void)
 152 {
 153         return -EINVAL;
 154 }
 155
 156 static inline void sve_user_disable(void) { BUILD_BUG(); }
 157 static inline void sve_user_enable(void) { BUILD_BUG(); }
 158
 159 static inline void sve_init_vq_map(void) { }
 160 static inline void sve_update_vq_map(void) { }
 161 static inline int sve_verify_vq_map(void) { return 0; }
 162 static inline void sve_setup(void) { }
 163
 164 #endif /* ! CONFIG_ARM64_SVE */
 165
 166 /* For use by EFI runtime services calls only */
 167 extern void __efi_fpsimd_begin(void);
 168 extern void __efi_fpsimd_end(void);
 169
 170 #endif
 171
 172 #endif