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 * $#-way unrolled NEON intrinsics math RAID-6 instruction set 23 * 24 * This file is postprocessed using unroll.awk 25 */ 26 27#include <arm_neon.h> 28 29typedef uint8x16_t unative_t; 30 31#define NBYTES(x) ((unative_t){x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x}) 32#define NSIZE sizeof(unative_t) 33 34/* 35 * The SHLBYTE() operation shifts each byte left by 1, *not* 36 * rolling over into the next byte 37 */ 38static inline unative_t SHLBYTE(unative_t v) 39{ 40 return vshlq_n_u8(v, 1); 41} 42 43/* 44 * The MASK() operation returns 0xFF in any byte for which the high 45 * bit is 1, 0x00 for any byte for which the high bit is 0. 46 */ 47static inline unative_t MASK(unative_t v) 48{ 49 const uint8x16_t temp = NBYTES(0); 50 return (unative_t)vcltq_s8((int8x16_t)v, (int8x16_t)temp); 51} 52 53void raid6_neon$#_gen_syndrome_real(int disks, unsigned long bytes, void **ptrs) 54{ 55 uint8_t **dptr = (uint8_t **)ptrs; 56 uint8_t *p, *q; 57 int d, z, z0; 58 59 register unative_t wd$$, wq$$, wp$$, w1$$, w2$$; 60 const unative_t x1d = NBYTES(0x1d); 61 62 z0 = disks - 3; /* Highest data disk */ 63 p = dptr[z0+1]; /* XOR parity */ 64 q = dptr[z0+2]; /* RS syndrome */ 65 66 for ( d = 0 ; d < bytes ; d += NSIZE*$# ) { 67 wq$$ = wp$$ = vld1q_u8(&dptr[z0][d+$$*NSIZE]); 68 for ( z = z0-1 ; z >= 0 ; z-- ) { 69 wd$$ = vld1q_u8(&dptr[z][d+$$*NSIZE]); 70 wp$$ = veorq_u8(wp$$, wd$$); 71 w2$$ = MASK(wq$$); 72 w1$$ = SHLBYTE(wq$$); 73 74 w2$$ = vandq_u8(w2$$, x1d); 75 w1$$ = veorq_u8(w1$$, w2$$); 76 wq$$ = veorq_u8(w1$$, wd$$); 77 } 78 vst1q_u8(&p[d+NSIZE*$$], wp$$); 79 vst1q_u8(&q[d+NSIZE*$$], wq$$); 80 } 81} 82 83void raid6_neon$#_xor_syndrome_real(int disks, int start, int stop, 84 unsigned long bytes, void **ptrs) 85{ 86 uint8_t **dptr = (uint8_t **)ptrs; 87 uint8_t *p, *q; 88 int d, z, z0; 89 90 register unative_t wd$$, wq$$, wp$$, w1$$, w2$$; 91 const unative_t x1d = NBYTES(0x1d); 92 93 z0 = stop; /* P/Q right side optimization */ 94 p = dptr[disks-2]; /* XOR parity */ 95 q = dptr[disks-1]; /* RS syndrome */ 96 97 for ( d = 0 ; d < bytes ; d += NSIZE*$# ) { 98 wq$$ = vld1q_u8(&dptr[z0][d+$$*NSIZE]); 99 wp$$ = veorq_u8(vld1q_u8(&p[d+$$*NSIZE]), wq$$); 100 101 /* P/Q data pages */ 102 for ( z = z0-1 ; z >= start ; z-- ) { 103 wd$$ = vld1q_u8(&dptr[z][d+$$*NSIZE]); 104 wp$$ = veorq_u8(wp$$, wd$$); 105 w2$$ = MASK(wq$$); 106 w1$$ = SHLBYTE(wq$$); 107 108 w2$$ = vandq_u8(w2$$, x1d); 109 w1$$ = veorq_u8(w1$$, w2$$); 110 wq$$ = veorq_u8(w1$$, wd$$); 111 } 112 /* P/Q left side optimization */ 113 for ( z = start-1 ; z >= 0 ; z-- ) { 114 w2$$ = MASK(wq$$); 115 w1$$ = SHLBYTE(wq$$); 116 117 w2$$ = vandq_u8(w2$$, x1d); 118 wq$$ = veorq_u8(w1$$, w2$$); 119 } 120 w1$$ = vld1q_u8(&q[d+NSIZE*$$]); 121 wq$$ = veorq_u8(wq$$, w1$$); 122 123 vst1q_u8(&p[d+NSIZE*$$], wp$$); 124 vst1q_u8(&q[d+NSIZE*$$], wq$$); 125 } 126} 127