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 unsigned int sve_get_vl(void);
  73
  74struct arm64_cpu_capabilities;
  75extern void sve_kernel_enable(const struct arm64_cpu_capabilities *__unused);
  76
  77extern u64 read_zcr_features(void);
  78
  79extern int __ro_after_init sve_max_vl;
  80extern int __ro_after_init sve_max_virtualisable_vl;
  81extern __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 */
  88static inline unsigned int __vq_to_bit(unsigned int vq)
  89{
  90        return SVE_VQ_MAX - vq;
  91}
  92
  93static 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 */
  99static 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
 106extern size_t sve_state_size(struct task_struct const *task);
 107
 108extern void sve_alloc(struct task_struct *task);
 109extern void fpsimd_release_task(struct task_struct *task);
 110extern void fpsimd_sync_to_sve(struct task_struct *task);
 111extern void sve_sync_to_fpsimd(struct task_struct *task);
 112extern void sve_sync_from_fpsimd_zeropad(struct task_struct *task);
 113
 114extern int sve_set_vector_length(struct task_struct *task,
 115                                 unsigned long vl, unsigned long flags);
 116
 117extern int sve_set_current_vl(unsigned long arg);
 118extern int sve_get_current_vl(void);
 119
 120static inline void sve_user_disable(void)
 121{
 122        sysreg_clear_set(cpacr_el1, CPACR_EL1_ZEN_EL0EN, 0);
 123}
 124
 125static 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 */
 134extern void __init sve_init_vq_map(void);
 135extern void sve_update_vq_map(void);
 136extern int sve_verify_vq_map(void);
 137extern void __init sve_setup(void);
 138
 139#else /* ! CONFIG_ARM64_SVE */
 140
 141static inline void sve_alloc(struct task_struct *task) { }
 142static inline void fpsimd_release_task(struct task_struct *task) { }
 143static inline void sve_sync_to_fpsimd(struct task_struct *task) { }
 144static inline void sve_sync_from_fpsimd_zeropad(struct task_struct *task) { }
 145
 146static inline int sve_set_current_vl(unsigned long arg)
 147{
 148        return -EINVAL;
 149}
 150
 151static inline int sve_get_current_vl(void)
 152{
 153        return -EINVAL;
 154}
 155
 156static inline void sve_user_disable(void) { BUILD_BUG(); }
 157static inline void sve_user_enable(void) { BUILD_BUG(); }
 158
 159static inline void sve_init_vq_map(void) { }
 160static inline void sve_update_vq_map(void) { }
 161static inline int sve_verify_vq_map(void) { return 0; }
 162static inline void sve_setup(void) { }
 163
 164#endif /* ! CONFIG_ARM64_SVE */
 165
 166/* For use by EFI runtime services calls only */
 167extern void __efi_fpsimd_begin(void);
 168extern void __efi_fpsimd_end(void);
 169
 170#endif
 171
 172#endif
 173