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 * $#-way unrolled NEON intrinsics math RAID-6 instruction set 23 * 24 * This file is postprocessed using unroll.awk 25 */ 26 27#include <arm_neon.h> 28 29typedef uint8x16_t unative_t; 30 31#define NBYTES(x) ((unative_t){x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x}) 32#define NSIZE sizeof(unative_t) 33 34/* 35 * The SHLBYTE() operation shifts each byte left by 1, *not* 36 * rolling over into the next byte 37 */ 38static inline unative_t SHLBYTE(unative_t v) 39{ 40 return vshlq_n_u8(v, 1); 41} 42 43/* 44 * The MASK() operation returns 0xFF in any byte for which the high 45 * bit is 1, 0x00 for any byte for which the high bit is 0. 46 */ 47static inline unative_t MASK(unative_t v) 48{ 49 return (unative_t)vshrq_n_s8((int8x16_t)v, 7); 50} 51 52static inline unative_t PMUL(unative_t v, unative_t u) 53{ 54 return (unative_t)vmulq_p8((poly8x16_t)v, (poly8x16_t)u); 55} 56 57void raid6_neon$#_gen_syndrome_real(int disks, unsigned long bytes, void **ptrs) 58{ 59 uint8_t **dptr = (uint8_t **)ptrs; 60 uint8_t *p, *q; 61 int d, z, z0; 62 63 register unative_t wd$$, wq$$, wp$$, w1$$, w2$$; 64 const unative_t x1d = NBYTES(0x1d); 65 66 z0 = disks - 3; /* Highest data disk */ 67 p = dptr[z0+1]; /* XOR parity */ 68 q = dptr[z0+2]; /* RS syndrome */ 69 70 for ( d = 0 ; d < bytes ; d += NSIZE*$# ) { 71 wq$$ = wp$$ = vld1q_u8(&dptr[z0][d+$$*NSIZE]); 72 for ( z = z0-1 ; z >= 0 ; z-- ) { 73 wd$$ = vld1q_u8(&dptr[z][d+$$*NSIZE]); 74 wp$$ = veorq_u8(wp$$, wd$$); 75 w2$$ = MASK(wq$$); 76 w1$$ = SHLBYTE(wq$$); 77 78 w2$$ = vandq_u8(w2$$, x1d); 79 w1$$ = veorq_u8(w1$$, w2$$); 80 wq$$ = veorq_u8(w1$$, wd$$); 81 } 82 vst1q_u8(&p[d+NSIZE*$$], wp$$); 83 vst1q_u8(&q[d+NSIZE*$$], wq$$); 84 } 85} 86 87void raid6_neon$#_xor_syndrome_real(int disks, int start, int stop, 88 unsigned long bytes, void **ptrs) 89{ 90 uint8_t **dptr = (uint8_t **)ptrs; 91 uint8_t *p, *q; 92 int d, z, z0; 93 94 register unative_t wd$$, wq$$, wp$$, w1$$, w2$$; 95 const unative_t x1d = NBYTES(0x1d); 96 97 z0 = stop; /* P/Q right side optimization */ 98 p = dptr[disks-2]; /* XOR parity */ 99 q = dptr[disks-1]; /* RS syndrome */ 100 101 for ( d = 0 ; d < bytes ; d += NSIZE*$# ) { 102 wq$$ = vld1q_u8(&dptr[z0][d+$$*NSIZE]); 103 wp$$ = veorq_u8(vld1q_u8(&p[d+$$*NSIZE]), wq$$); 104 105 /* P/Q data pages */ 106 for ( z = z0-1 ; z >= start ; z-- ) { 107 wd$$ = vld1q_u8(&dptr[z][d+$$*NSIZE]); 108 wp$$ = veorq_u8(wp$$, wd$$); 109 w2$$ = MASK(wq$$); 110 w1$$ = SHLBYTE(wq$$); 111 112 w2$$ = vandq_u8(w2$$, x1d); 113 w1$$ = veorq_u8(w1$$, w2$$); 114 wq$$ = veorq_u8(w1$$, wd$$); 115 } 116 /* P/Q left side optimization */ 117 for ( z = start-1 ; z >= 3 ; z -= 4 ) { 118 w2$$ = vshrq_n_u8(wq$$, 4); 119 w1$$ = vshlq_n_u8(wq$$, 4); 120 121 w2$$ = PMUL(w2$$, x1d); 122 wq$$ = veorq_u8(w1$$, w2$$); 123 } 124 125 switch (z) { 126 case 2: 127 w2$$ = vshrq_n_u8(wq$$, 5); 128 w1$$ = vshlq_n_u8(wq$$, 3); 129 130 w2$$ = PMUL(w2$$, x1d); 131 wq$$ = veorq_u8(w1$$, w2$$); 132 break; 133 case 1: 134 w2$$ = vshrq_n_u8(wq$$, 6); 135 w1$$ = vshlq_n_u8(wq$$, 2); 136 137 w2$$ = PMUL(w2$$, x1d); 138 wq$$ = veorq_u8(w1$$, w2$$); 139 break; 140 case 0: 141 w2$$ = MASK(wq$$); 142 w1$$ = SHLBYTE(wq$$); 143 144 w2$$ = vandq_u8(w2$$, x1d); 145 wq$$ = veorq_u8(w1$$, w2$$); 146 } 147 w1$$ = vld1q_u8(&q[d+NSIZE*$$]); 148 wq$$ = veorq_u8(wq$$, w1$$); 149 150 vst1q_u8(&p[d+NSIZE*$$], wp$$); 151 vst1q_u8(&q[d+NSIZE*$$], wq$$); 152 } 153} 154