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_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
 188