LXR linux/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#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_state_to_cpu(struct user_fpsimd_state *state,
  49                                     void *sve_state, unsigned int sve_vl);
  50
  51extern void fpsimd_flush_task_state(struct task_struct *target);
  52extern void fpsimd_save_and_flush_cpu_state(void);
  53
  54/* Maximum VL that SVE VL-agnostic software can transparently support */
  55#define SVE_VL_ARCH_MAX 0x100
  56
  57/* Offset of FFR in the SVE register dump */
  58static inline size_t sve_ffr_offset(int vl)
  59{
  60        return SVE_SIG_FFR_OFFSET(sve_vq_from_vl(vl)) - SVE_SIG_REGS_OFFSET;
  61}
  62
  63static inline void *sve_pffr(struct thread_struct *thread)
  64{
  65        return (char *)thread->sve_state + sve_ffr_offset(thread->sve_vl);
  66}
  67
  68extern void sve_save_state(void *state, u32 *pfpsr);
  69extern void sve_load_state(void const *state, u32 const *pfpsr,
  70                           unsigned long vq_minus_1);
  71extern void sve_flush_live(unsigned long vq_minus_1);
  72extern void sve_load_from_fpsimd_state(struct user_fpsimd_state const *state,
  73                                       unsigned long vq_minus_1);
  74extern unsigned int sve_get_vl(void);
  75extern void sve_set_vq(unsigned long vq_minus_1);
  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#define sve_cond_update_zcr_vq(val, reg)                \
 134        do {                                            \
 135                u64 __zcr = read_sysreg_s((reg));       \
 136                u64 __new = __zcr & ~ZCR_ELx_LEN_MASK;  \
 137                __new |= (val) & ZCR_ELx_LEN_MASK;      \
 138                if (__zcr != __new)                     \
 139                        write_sysreg_s(__new, (reg));   \
 140        } while (0)
 141
 142/*
 143 * Probing and setup functions.
 144 * Calls to these functions must be serialised with one another.
 145 */
 146extern void __init sve_init_vq_map(void);
 147extern void sve_update_vq_map(void);
 148extern int sve_verify_vq_map(void);
 149extern void __init sve_setup(void);
 150
 151#else /* ! CONFIG_ARM64_SVE */
 152
 153static inline void sve_alloc(struct task_struct *task) { }
 154static inline void fpsimd_release_task(struct task_struct *task) { }
 155static inline void sve_sync_to_fpsimd(struct task_struct *task) { }
 156static inline void sve_sync_from_fpsimd_zeropad(struct task_struct *task) { }
 157
 158static inline int sve_set_current_vl(unsigned long arg)
 159{
 160        return -EINVAL;
 161}
 162
 163static inline int sve_get_current_vl(void)
 164{
 165        return -EINVAL;
 166}
 167
 168static inline void sve_user_disable(void) { BUILD_BUG(); }
 169static inline void sve_user_enable(void) { BUILD_BUG(); }
 170
 171#define sve_cond_update_zcr_vq(val, reg) do { } while (0)
 172
 173static inline void sve_init_vq_map(void) { }
 174static inline void sve_update_vq_map(void) { }
 175static inline int sve_verify_vq_map(void) { return 0; }
 176static inline void sve_setup(void) { }
 177
 178#endif /* ! CONFIG_ARM64_SVE */
 179
 180/* For use by EFI runtime services calls only */
 181extern void __efi_fpsimd_begin(void);
 182extern void __efi_fpsimd_end(void);
 183
 184#endif
 185
 186#endif
 187