include/os/linux/kernel/linux/simd_aarch64.h

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or https://opensource.org/licenses/CDDL-1.0.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright (C) 2016 Romain Dolbeau <romain@dolbeau.org>.
  24  * Copyright (C) 2022 Tino Reichardt <milky-zfs@mcmilk.de>
  25  * Copyright (C) 2022 Sebastian Gottschall <s.gottschall@dd-wrt.com>
  26  */
  27
  28 /*
  29  * USER API:
  30  *
  31  * Kernel fpu methods:
  32  *      kfpu_allowed()
  33  *      kfpu_begin()
  34  *      kfpu_end()
  35  *      kfpu_init()
  36  *      kfpu_fini()
  37  *
  38  * SIMD support:
  39  *
  40  * Following functions should be called to determine whether CPU feature
  41  * is supported. All functions are usable in kernel and user space.
  42  * If a SIMD algorithm is using more than one instruction set
  43  * all relevant feature test functions should be called.
  44  *
  45  * Supported features:
  46  *   zfs_neon_available()
  47  *   zfs_sha256_available()
  48  *   zfs_sha512_available()
  49  */
  50
  51 #ifndef _LINUX_SIMD_AARCH64_H
  52 #define _LINUX_SIMD_AARCH64_H
  53
  54 #include <sys/types.h>
  55 #include <asm/neon.h>
  56 #include <asm/elf.h>
  57 #include <asm/hwcap.h>
  58 #include <linux/version.h>
  59 #include <asm/sysreg.h>
  60
  61 #define ID_AA64PFR0_EL1         sys_reg(3, 0, 0, 1, 0)
  62 #define ID_AA64ISAR0_EL1        sys_reg(3, 0, 0, 6, 0)
  63
  64 #if (defined(HAVE_KERNEL_NEON) && defined(CONFIG_KERNEL_MODE_NEON))
  65 #define kfpu_allowed()          1
  66 #define kfpu_begin()            kernel_neon_begin()
  67 #define kfpu_end()              kernel_neon_end()
  68 #else
  69 #define kfpu_allowed()          0
  70 #define kfpu_begin()            do {} while (0)
  71 #define kfpu_end()              do {} while (0)
  72 #endif
  73 #define kfpu_init()             (0)
  74 #define kfpu_fini()             do {} while (0)
  75
  76 #define get_ftr(id) {                           \
  77         unsigned long __val;                    \
  78         asm("mrs %0, "#id : "=r" (__val));      \
  79         __val;                                  \
  80 }
  81
  82 /*
  83  * Check if NEON is available
  84  */
  85 static inline boolean_t
  86 zfs_neon_available(void)
  87 {
  88         unsigned long ftr = ((get_ftr(ID_AA64PFR0_EL1)) >> 16) & 0xf;
  89         return (ftr == 0 || ftr == 1);
  90 }
  91
  92 /*
  93  * Check if SHA256 is available
  94  */
  95 static inline boolean_t
  96 zfs_sha256_available(void)
  97 {
  98         unsigned long ftr = ((get_ftr(ID_AA64ISAR0_EL1)) >> 12) & 0x3;
  99         return (ftr & 0x1);
 100 }
 101
 102 /*
 103  * Check if SHA512 is available
 104  */
 105 static inline boolean_t
 106 zfs_sha512_available(void)
 107 {
 108         unsigned long ftr = ((get_ftr(ID_AA64ISAR0_EL1)) >> 12) & 0x3;
 109         return (ftr & 0x2);
 110 }
 111
 112 #endif /* _LINUX_SIMD_AARCH64_H */