xref: /linux/lib/raid6/recov_neon_inner.c (revision 69bfec7548f4c1595bac0e3ddfc0458a5af31f4c)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012 Intel Corporation
4  * Copyright (C) 2017 Linaro Ltd. <ard.biesheuvel@linaro.org>
5  */
6 
7 #include <arm_neon.h>
8 
9 #ifdef CONFIG_ARM
10 /*
11  * AArch32 does not provide this intrinsic natively because it does not
12  * implement the underlying instruction. AArch32 only provides a 64-bit
13  * wide vtbl.8 instruction, so use that instead.
14  */
15 static uint8x16_t vqtbl1q_u8(uint8x16_t a, uint8x16_t b)
16 {
17 	union {
18 		uint8x16_t	val;
19 		uint8x8x2_t	pair;
20 	} __a = { a };
21 
22 	return vcombine_u8(vtbl2_u8(__a.pair, vget_low_u8(b)),
23 			   vtbl2_u8(__a.pair, vget_high_u8(b)));
24 }
25 #endif
26 
27 void __raid6_2data_recov_neon(int bytes, uint8_t *p, uint8_t *q, uint8_t *dp,
28 			      uint8_t *dq, const uint8_t *pbmul,
29 			      const uint8_t *qmul)
30 {
31 	uint8x16_t pm0 = vld1q_u8(pbmul);
32 	uint8x16_t pm1 = vld1q_u8(pbmul + 16);
33 	uint8x16_t qm0 = vld1q_u8(qmul);
34 	uint8x16_t qm1 = vld1q_u8(qmul + 16);
35 	uint8x16_t x0f = vdupq_n_u8(0x0f);
36 
37 	/*
38 	 * while ( bytes-- ) {
39 	 *	uint8_t px, qx, db;
40 	 *
41 	 *	px    = *p ^ *dp;
42 	 *	qx    = qmul[*q ^ *dq];
43 	 *	*dq++ = db = pbmul[px] ^ qx;
44 	 *	*dp++ = db ^ px;
45 	 *	p++; q++;
46 	 * }
47 	 */
48 
49 	while (bytes) {
50 		uint8x16_t vx, vy, px, qx, db;
51 
52 		px = veorq_u8(vld1q_u8(p), vld1q_u8(dp));
53 		vx = veorq_u8(vld1q_u8(q), vld1q_u8(dq));
54 
55 		vy = vshrq_n_u8(vx, 4);
56 		vx = vqtbl1q_u8(qm0, vandq_u8(vx, x0f));
57 		vy = vqtbl1q_u8(qm1, vy);
58 		qx = veorq_u8(vx, vy);
59 
60 		vy = vshrq_n_u8(px, 4);
61 		vx = vqtbl1q_u8(pm0, vandq_u8(px, x0f));
62 		vy = vqtbl1q_u8(pm1, vy);
63 		vx = veorq_u8(vx, vy);
64 		db = veorq_u8(vx, qx);
65 
66 		vst1q_u8(dq, db);
67 		vst1q_u8(dp, veorq_u8(db, px));
68 
69 		bytes -= 16;
70 		p += 16;
71 		q += 16;
72 		dp += 16;
73 		dq += 16;
74 	}
75 }
76 
77 void __raid6_datap_recov_neon(int bytes, uint8_t *p, uint8_t *q, uint8_t *dq,
78 			      const uint8_t *qmul)
79 {
80 	uint8x16_t qm0 = vld1q_u8(qmul);
81 	uint8x16_t qm1 = vld1q_u8(qmul + 16);
82 	uint8x16_t x0f = vdupq_n_u8(0x0f);
83 
84 	/*
85 	 * while (bytes--) {
86 	 *	*p++ ^= *dq = qmul[*q ^ *dq];
87 	 *	q++; dq++;
88 	 * }
89 	 */
90 
91 	while (bytes) {
92 		uint8x16_t vx, vy;
93 
94 		vx = veorq_u8(vld1q_u8(q), vld1q_u8(dq));
95 
96 		vy = vshrq_n_u8(vx, 4);
97 		vx = vqtbl1q_u8(qm0, vandq_u8(vx, x0f));
98 		vy = vqtbl1q_u8(qm1, vy);
99 		vx = veorq_u8(vx, vy);
100 		vy = veorq_u8(vx, vld1q_u8(p));
101 
102 		vst1q_u8(dq, vx);
103 		vst1q_u8(p, vy);
104 
105 		bytes -= 16;
106 		p += 16;
107 		q += 16;
108 		dq += 16;
109 	}
110 }
111