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1/* -----------------------------------------------------------------------2 *3 * neon.uc - RAID-6 syndrome calculation using ARM NEON instructions4 *5 * Copyright (C) 2012 Rob Herring6 * Copyright (C) 2015 Linaro Ltd. <ard.biesheuvel@linaro.org>7 *8 * Based on altivec.uc:9 * Copyright 2002-2004 H. Peter Anvin - All Rights Reserved10 *11 * This program is free software; you can redistribute it and/or modify12 * it under the terms of the GNU General Public License as published by13 * the Free Software Foundation, Inc., 53 Temple Place Ste 330,14 * Boston MA 02111-1307, USA; either version 2 of the License, or15 * (at your option) any later version; incorporated herein by reference.16 *17 * ----------------------------------------------------------------------- */18 19/*20 * neon$#.c21 *22 * $#-way unrolled NEON intrinsics math RAID-6 instruction set23 *24 * This file is postprocessed using unroll.awk25 */26 27#include <arm_neon.h>28#include "neon.h"29 30typedef uint8x16_t unative_t;31 32#define NSIZE sizeof(unative_t)33 34/*35 * The SHLBYTE() operation shifts each byte left by 1, *not*36 * rolling over into the next byte37 */38static inline unative_t SHLBYTE(unative_t v)39{40 return vshlq_n_u8(v, 1);41}42 43/*44 * The MASK() operation returns 0xFF in any byte for which the high45 * bit is 1, 0x00 for any byte for which the high bit is 0.46 */47static inline unative_t MASK(unative_t v)48{49 return (unative_t)vshrq_n_s8((int8x16_t)v, 7);50}51 52static inline unative_t PMUL(unative_t v, unative_t u)53{54 return (unative_t)vmulq_p8((poly8x16_t)v, (poly8x16_t)u);55}56 57void raid6_neon$#_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$$;64 const unative_t x1d = vdupq_n_u8(0x1d);65 66 z0 = disks - 3; /* Highest data disk */67 p = dptr[z0+1]; /* XOR parity */68 q = dptr[z0+2]; /* RS syndrome */69 70 for ( d = 0 ; d < bytes ; d += NSIZE*$# ) {71 wq$$ = 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 = vdupq_n_u8(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