xref: /openbmc/linux/lib/raid6/recov_neon_inner.c (revision 83146efc)
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 #include "neon.h"
9 
10 #ifdef CONFIG_ARM
11 /*
12  * AArch32 does not provide this intrinsic natively because it does not
13  * implement the underlying instruction. AArch32 only provides a 64-bit
14  * wide vtbl.8 instruction, so use that instead.
15  */
16 static uint8x16_t vqtbl1q_u8(uint8x16_t a, uint8x16_t b)
17 {
18 	union {
19 		uint8x16_t	val;
20 		uint8x8x2_t	pair;
21 	} __a = { a };
22 
23 	return vcombine_u8(vtbl2_u8(__a.pair, vget_low_u8(b)),
24 			   vtbl2_u8(__a.pair, vget_high_u8(b)));
25 }
26 #endif
27 
28 void __raid6_2data_recov_neon(int bytes, uint8_t *p, uint8_t *q, uint8_t *dp,
29 			      uint8_t *dq, const uint8_t *pbmul,
30 			      const uint8_t *qmul)
31 {
32 	uint8x16_t pm0 = vld1q_u8(pbmul);
33 	uint8x16_t pm1 = vld1q_u8(pbmul + 16);
34 	uint8x16_t qm0 = vld1q_u8(qmul);
35 	uint8x16_t qm1 = vld1q_u8(qmul + 16);
36 	uint8x16_t x0f = vdupq_n_u8(0x0f);
37 
38 	/*
39 	 * while ( bytes-- ) {
40 	 *	uint8_t px, qx, db;
41 	 *
42 	 *	px    = *p ^ *dp;
43 	 *	qx    = qmul[*q ^ *dq];
44 	 *	*dq++ = db = pbmul[px] ^ qx;
45 	 *	*dp++ = db ^ px;
46 	 *	p++; q++;
47 	 * }
48 	 */
49 
50 	while (bytes) {
51 		uint8x16_t vx, vy, px, qx, db;
52 
53 		px = veorq_u8(vld1q_u8(p), vld1q_u8(dp));
54 		vx = veorq_u8(vld1q_u8(q), vld1q_u8(dq));
55 
56 		vy = vshrq_n_u8(vx, 4);
57 		vx = vqtbl1q_u8(qm0, vandq_u8(vx, x0f));
58 		vy = vqtbl1q_u8(qm1, vy);
59 		qx = veorq_u8(vx, vy);
60 
61 		vy = vshrq_n_u8(px, 4);
62 		vx = vqtbl1q_u8(pm0, vandq_u8(px, x0f));
63 		vy = vqtbl1q_u8(pm1, vy);
64 		vx = veorq_u8(vx, vy);
65 		db = veorq_u8(vx, qx);
66 
67 		vst1q_u8(dq, db);
68 		vst1q_u8(dp, veorq_u8(db, px));
69 
70 		bytes -= 16;
71 		p += 16;
72 		q += 16;
73 		dp += 16;
74 		dq += 16;
75 	}
76 }
77 
78 void __raid6_datap_recov_neon(int bytes, uint8_t *p, uint8_t *q, uint8_t *dq,
79 			      const uint8_t *qmul)
80 {
81 	uint8x16_t qm0 = vld1q_u8(qmul);
82 	uint8x16_t qm1 = vld1q_u8(qmul + 16);
83 	uint8x16_t x0f = vdupq_n_u8(0x0f);
84 
85 	/*
86 	 * while (bytes--) {
87 	 *	*p++ ^= *dq = qmul[*q ^ *dq];
88 	 *	q++; dq++;
89 	 * }
90 	 */
91 
92 	while (bytes) {
93 		uint8x16_t vx, vy;
94 
95 		vx = veorq_u8(vld1q_u8(q), vld1q_u8(dq));
96 
97 		vy = vshrq_n_u8(vx, 4);
98 		vx = vqtbl1q_u8(qm0, vandq_u8(vx, x0f));
99 		vy = vqtbl1q_u8(qm1, vy);
100 		vx = veorq_u8(vx, vy);
101 		vy = veorq_u8(vx, vld1q_u8(p));
102 
103 		vst1q_u8(dq, vx);
104 		vst1q_u8(p, vy);
105 
106 		bytes -= 16;
107 		p += 16;
108 		q += 16;
109 		dq += 16;
110 	}
111 }
112