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 http://www.opensolaris.org/os/licensing. 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 * Copyright (C) 2019 Romain Dolbeau 23 * <romain.dolbeau@european-processor-initiative.eu> 24 */ 25 26 /* 27 * USER API: 28 * 29 * Kernel fpu methods: 30 * kfpu_allowed() 31 * kfpu_begin() 32 * kfpu_end() 33 * kfpu_init() 34 * kfpu_fini() 35 * 36 * SIMD support: 37 * 38 * Following functions should be called to determine whether CPU feature 39 * is supported. All functions are usable in kernel and user space. 40 * If a SIMD algorithm is using more than one instruction set 41 * all relevant feature test functions should be called. 42 * 43 * Supported features: 44 * zfs_altivec_available() 45 */ 46 47 #ifndef _LINUX_SIMD_POWERPC_H 48 #define _LINUX_SIMD_POWERPC_H 49 50 /* only for __powerpc__ */ 51 #if defined(__powerpc__) 52 53 #include <linux/preempt.h> 54 #include <linux/export.h> 55 #include <linux/sched.h> 56 #include <asm/switch_to.h> 57 #include <sys/types.h> 58 #include <linux/version.h> 59 60 #define kfpu_allowed() 1 61 62 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 5, 0) 63 #define kfpu_end() \ 64 { \ 65 disable_kernel_vsx(); \ 66 disable_kernel_altivec(); \ 67 preempt_enable(); \ 68 } 69 #define kfpu_begin() \ 70 { \ 71 preempt_disable(); \ 72 enable_kernel_altivec(); \ 73 enable_kernel_vsx(); \ 74 } 75 #else 76 /* seems that before 4.5 no-one bothered */ 77 #define kfpu_begin() 78 #define kfpu_end() preempt_enable() 79 #endif 80 #define kfpu_init() 0 81 #define kfpu_fini() ((void) 0) 82 83 static inline boolean_t 84 zfs_vsx_available(void) 85 { 86 boolean_t res; 87 #if defined(__powerpc64__) 88 u64 msr; 89 #else 90 u32 msr; 91 #endif 92 kfpu_begin(); 93 __asm volatile("mfmsr %0" : "=r"(msr)); 94 res = (msr & 0x800000) != 0; 95 kfpu_end(); 96 return (res); 97 } 98 99 /* 100 * Check if AltiVec instruction set is available 101 */ 102 static inline boolean_t 103 zfs_altivec_available(void) 104 { 105 boolean_t res; 106 /* suggested by macallan at netbsd dot org */ 107 #if defined(__powerpc64__) 108 u64 msr; 109 #else 110 u32 msr; 111 #endif 112 kfpu_begin(); 113 __asm volatile("mfmsr %0" : "=r"(msr)); 114 /* 115 * 64 bits -> need to check bit 38 116 * Power ISA Version 3.0B 117 * p944 118 * 32 bits -> Need to check bit 6 119 * AltiVec Technology Programming Environments Manual 120 * p49 (2-9) 121 * They are the same, as ppc counts 'backward' ... 122 */ 123 res = (msr & 0x2000000) != 0; 124 kfpu_end(); 125 return (res); 126 } 127 #endif /* defined(__powerpc) */ 128 129 #endif /* _LINUX_SIMD_POWERPC_H */ 130