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
 13static 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 */
 24static 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
 36void __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
 85void __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}