1/* ----------------------------------------------------------------------- 2 * 3 * neon.uc - RAID-6 syndrome calculation using ARM NEON instructions 4 * 5 * Copyright (C) 2012 Rob Herring 6 * Copyright (C) 2015 Linaro Ltd. <ard.biesheuvel@linaro.org> 7 * 8 * Based on altivec.uc: 9 * Copyright 2002-2004 H. Peter Anvin - All Rights Reserved 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License as published by 13 * the Free Software Foundation, Inc., 53 Temple Place Ste 330, 14 * Boston MA 02111-1307, USA; either version 2 of the License, or 15 * (at your option) any later version; incorporated herein by reference. 16 * 17 * ----------------------------------------------------------------------- */ 18 19/* 20 * neon$#.c 21 * 22 * $#-way unrolled NEON intrinsics math RAID-6 instruction set 23 * 24 * This file is postprocessed using unroll.awk 25 */ 26 27#include <arm_neon.h> 28 29typedef uint8x16_t unative_t; 30 31#define NSIZE sizeof(unative_t) 32 33/* 34 * The SHLBYTE() operation shifts each byte left by 1, *not* 35 * rolling over into the next byte 36 */ 37static inline unative_t SHLBYTE(unative_t v) 38{ 39 return vshlq_n_u8(v, 1); 40} 41 42/* 43 * The MASK() operation returns 0xFF in any byte for which the high 44 * bit is 1, 0x00 for any byte for which the high bit is 0. 45 */ 46static inline unative_t MASK(unative_t v) 47{ 48 return (unative_t)vshrq_n_s8((int8x16_t)v, 7); 49} 50 51static inline unative_t PMUL(unative_t v, unative_t u) 52{ 53 return (unative_t)vmulq_p8((poly8x16_t)v, (poly8x16_t)u); 54} 55 56void raid6_neon$#_gen_syndrome_real(int disks, unsigned long bytes, void **ptrs) 57{ 58 uint8_t **dptr = (uint8_t **)ptrs; 59 uint8_t *p, *q; 60 int d, z, z0; 61 62 register unative_t wd$$, wq$$, wp$$, w1$$, w2$$; 63 const unative_t x1d = vdupq_n_u8(0x1d); 64 65 z0 = disks - 3; /* Highest data disk */ 66 p = dptr[z0+1]; /* XOR parity */ 67 q = dptr[z0+2]; /* RS syndrome */ 68 69 for ( d = 0 ; d < bytes ; d += NSIZE*$# ) { 70 wq$$ = wp$$ = vld1q_u8(&dptr[z0][d+$$*NSIZE]); 71 for ( z = z0-1 ; z >= 0 ; z-- ) { 72 wd$$ = vld1q_u8(&dptr[z][d+$$*NSIZE]); 73 wp$$ = veorq_u8(wp$$, wd$$); 74 w2$$ = MASK(wq$$); 75 w1$$ = SHLBYTE(wq$$); 76 77 w2$$ = vandq_u8(w2$$, x1d); 78 w1$$ = veorq_u8(w1$$, w2$$); 79 wq$$ = veorq_u8(w1$$, wd$$); 80 } 81 vst1q_u8(&p[d+NSIZE*$$], wp$$); 82 vst1q_u8(&q[d+NSIZE*$$], wq$$); 83 } 84} 85 86void raid6_neon$#_xor_syndrome_real(int disks, int start, int stop, 87 unsigned long bytes, void **ptrs) 88{ 89 uint8_t **dptr = (uint8_t **)ptrs; 90 uint8_t *p, *q; 91 int d, z, z0; 92 93 register unative_t wd$$, wq$$, wp$$, w1$$, w2$$; 94 const unative_t x1d = vdupq_n_u8(0x1d); 95 96 z0 = stop; /* P/Q right side optimization */ 97 p = dptr[disks-2]; /* XOR parity */ 98 q = dptr[disks-1]; /* RS syndrome */ 99 100 for ( d = 0 ; d < bytes ; d += NSIZE*$# ) { 101 wq$$ = vld1q_u8(&dptr[z0][d+$$*NSIZE]); 102 wp$$ = veorq_u8(vld1q_u8(&p[d+$$*NSIZE]), wq$$); 103 104 /* P/Q data pages */ 105 for ( z = z0-1 ; z >= start ; z-- ) { 106 wd$$ = vld1q_u8(&dptr[z][d+$$*NSIZE]); 107 wp$$ = veorq_u8(wp$$, wd$$); 108 w2$$ = MASK(wq$$); 109 w1$$ = SHLBYTE(wq$$); 110 111 w2$$ = vandq_u8(w2$$, x1d); 112 w1$$ = veorq_u8(w1$$, w2$$); 113 wq$$ = veorq_u8(w1$$, wd$$); 114 } 115 /* P/Q left side optimization */ 116 for ( z = start-1 ; z >= 3 ; z -= 4 ) { 117 w2$$ = vshrq_n_u8(wq$$, 4); 118 w1$$ = vshlq_n_u8(wq$$, 4); 119 120 w2$$ = PMUL(w2$$, x1d); 121 wq$$ = veorq_u8(w1$$, w2$$); 122 } 123 124 switch (z) { 125 case 2: 126 w2$$ = vshrq_n_u8(wq$$, 5); 127 w1$$ = vshlq_n_u8(wq$$, 3); 128 129 w2$$ = PMUL(w2$$, x1d); 130 wq$$ = veorq_u8(w1$$, w2$$); 131 break; 132 case 1: 133 w2$$ = vshrq_n_u8(wq$$, 6); 134 w1$$ = vshlq_n_u8(wq$$, 2); 135 136 w2$$ = PMUL(w2$$, x1d); 137 wq$$ = veorq_u8(w1$$, w2$$); 138 break; 139 case 0: 140 w2$$ = MASK(wq$$); 141 w1$$ = SHLBYTE(wq$$); 142 143 w2$$ = vandq_u8(w2$$, x1d); 144 wq$$ = veorq_u8(w1$$, w2$$); 145 } 146 w1$$ = vld1q_u8(&q[d+NSIZE*$$]); 147 wq$$ = veorq_u8(wq$$, w1$$); 148 149 vst1q_u8(&p[d+NSIZE*$$], wp$$); 150 vst1q_u8(&q[d+NSIZE*$$], wq$$); 151 } 152} 153