lib/raid6/recov_neon_inner.c

   1 /*
   2  * Copyright (C) 2012 Intel Corporation
   3  * Copyright (C) 2017 Linaro Ltd. <ard.biesheuvel@linaro.org>
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License
   7  * as published by the Free Software Foundation; version 2
   8  * of the License.
   9  */
  10
  11 #include <arm_neon.h>
  12
  13 static const uint8x16_t x0f = {
  14         0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f,
  15         0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f,
  16 };
  17
  18 #ifdef CONFIG_ARM
  19 /*
  20  * AArch32 does not provide this intrinsic natively because it does not
  21  * implement the underlying instruction. AArch32 only provides a 64-bit
  22  * wide vtbl.8 instruction, so use that instead.
  23  */
  24 static uint8x16_t vqtbl1q_u8(uint8x16_t a, uint8x16_t b)
  25 {
  26         union {
  27                 uint8x16_t      val;
  28                 uint8x8x2_t     pair;
  29         } __a = { a };
  30
  31         return vcombine_u8(vtbl2_u8(__a.pair, vget_low_u8(b)),
  32                            vtbl2_u8(__a.pair, vget_high_u8(b)));
  33 }
  34 #endif
  35
  36 void __raid6_2data_recov_neon(int bytes, uint8_t *p, uint8_t *q, uint8_t *dp,
  37                               uint8_t *dq, const uint8_t *pbmul,
  38                               const uint8_t *qmul)
  39 {
  40         uint8x16_t pm0 = vld1q_u8(pbmul);
  41         uint8x16_t pm1 = vld1q_u8(pbmul + 16);
  42         uint8x16_t qm0 = vld1q_u8(qmul);
  43         uint8x16_t qm1 = vld1q_u8(qmul + 16);
  44
  45         /*
  46          * while ( bytes-- ) {
  47          *      uint8_t px, qx, db;
  48          *
  49          *      px    = *p ^ *dp;
  50          *      qx    = qmul[*q ^ *dq];
  51          *      *dq++ = db = pbmul[px] ^ qx;
  52          *      *dp++ = db ^ px;
  53          *      p++; q++;
  54          * }
  55          */
  56
  57         while (bytes) {
  58                 uint8x16_t vx, vy, px, qx, db;
  59
  60                 px = veorq_u8(vld1q_u8(p), vld1q_u8(dp));
  61                 vx = veorq_u8(vld1q_u8(q), vld1q_u8(dq));
  62
  63                 vy = (uint8x16_t)vshrq_n_s16((int16x8_t)vx, 4);
  64                 vx = vqtbl1q_u8(qm0, vandq_u8(vx, x0f));
  65                 vy = vqtbl1q_u8(qm1, vandq_u8(vy, x0f));
  66                 qx = veorq_u8(vx, vy);
  67
  68                 vy = (uint8x16_t)vshrq_n_s16((int16x8_t)px, 4);
  69                 vx = vqtbl1q_u8(pm0, vandq_u8(px, x0f));
  70                 vy = vqtbl1q_u8(pm1, vandq_u8(vy, x0f));
  71                 vx = veorq_u8(vx, vy);
  72                 db = veorq_u8(vx, qx);
  73
  74                 vst1q_u8(dq, db);
  75                 vst1q_u8(dp, veorq_u8(db, px));
  76
  77                 bytes -= 16;
  78                 p += 16;
  79                 q += 16;
  80                 dp += 16;
  81                 dq += 16;
  82         }
  83 }
  84
  85 void __raid6_datap_recov_neon(int bytes, uint8_t *p, uint8_t *q, uint8_t *dq,
  86                               const uint8_t *qmul)
  87 {
  88         uint8x16_t qm0 = vld1q_u8(qmul);
  89         uint8x16_t qm1 = vld1q_u8(qmul + 16);
  90
  91         /*
  92          * while (bytes--) {
  93          *      *p++ ^= *dq = qmul[*q ^ *dq];
  94          *      q++; dq++;
  95          * }
  96          */
  97
  98         while (bytes) {
  99                 uint8x16_t vx, vy;
 100
 101                 vx = veorq_u8(vld1q_u8(q), vld1q_u8(dq));
 102
 103                 vy = (uint8x16_t)vshrq_n_s16((int16x8_t)vx, 4);
 104                 vx = vqtbl1q_u8(qm0, vandq_u8(vx, x0f));
 105                 vy = vqtbl1q_u8(qm1, vandq_u8(vy, x0f));
 106                 vx = veorq_u8(vx, vy);
 107                 vy = veorq_u8(vx, vld1q_u8(p));
 108
 109                 vst1q_u8(dq, vx);
 110                 vst1q_u8(p, vy);
 111
 112                 bytes -= 16;
 113                 p += 16;
 114                 q += 16;
 115                 dq += 16;
 116         }
 117 }