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1/* -*- linux-c -*- ------------------------------------------------------- *
2 *
3 *   Copyright 2002 H. Peter Anvin - All Rights Reserved
4 *   Copyright 2012 Tilera Corporation - All Rights Reserved
5 *
6 *   This program is free software; you can redistribute it and/or modify
7 *   it under the terms of the GNU General Public License as published by
8 *   the Free Software Foundation, Inc., 53 Temple Place Ste 330,
9 *   Boston MA 02111-1307, USA; either version 2 of the License, or
10 *   (at your option) any later version; incorporated herein by reference.
11 *
12 * ----------------------------------------------------------------------- */
13
14/*
15 * tilegx$#.c
16 *
17 * $#-way unrolled TILE-Gx SIMD for RAID-6 math.
18 *
19 * This file is postprocessed using unroll.awk.
20 *
21 */
22
23#include <linux/raid/pq.h>
24
25/* Create 8 byte copies of constant byte */
26# define NBYTES(x) (__insn_v1addi(0, x))
27# define NSIZE  8
28
29/*
30 * The SHLBYTE() operation shifts each byte left by 1, *not*
31 * rolling over into the next byte
32 */
33static inline __attribute_const__ u64 SHLBYTE(u64 v)
34{
35	/* Vector One Byte Shift Left Immediate. */
36	return __insn_v1shli(v, 1);
37}
38
39/*
40 * The MASK() operation returns 0xFF in any byte for which the high
41 * bit is 1, 0x00 for any byte for which the high bit is 0.
42 */
43static inline __attribute_const__ u64 MASK(u64 v)
44{
45	/* Vector One Byte Shift Right Signed Immediate. */
46	return __insn_v1shrsi(v, 7);
47}
48
49
50void raid6_tilegx$#_gen_syndrome(int disks, size_t bytes, void **ptrs)
51{
52	u8 **dptr = (u8 **)ptrs;
53	u64 *p, *q;
54	int d, z, z0;
55
56	u64 wd$$, wq$$, wp$$, w1$$, w2$$;
57	u64 x1d = NBYTES(0x1d);
58	u64 * z0ptr;
59
60	z0 = disks - 3;			/* Highest data disk */
61	p = (u64 *)dptr[z0+1];	/* XOR parity */
62	q = (u64 *)dptr[z0+2];	/* RS syndrome */
63
64	z0ptr = (u64 *)&dptr[z0][0];
65	for ( d = 0 ; d < bytes ; d += NSIZE*$# ) {
66		wq$$ = wp$$ = *z0ptr++;
67		for ( z = z0-1 ; z >= 0 ; z-- ) {
68			wd$$ = *(u64 *)&dptr[z][d+$$*NSIZE];
69			wp$$ = wp$$ ^ wd$$;
70			w2$$ = MASK(wq$$);
71			w1$$ = SHLBYTE(wq$$);
72			w2$$ = w2$$ & x1d;
73			w1$$ = w1$$ ^ w2$$;
74			wq$$ = w1$$ ^ wd$$;
75		}
76		*p++ = wp$$;
77		*q++ = wq$$;
78	}
79}
80
81const struct raid6_calls raid6_tilegx$# = {
82	raid6_tilegx$#_gen_syndrome,
83	NULL,			/* XOR not yet implemented */
84	NULL,
85	"tilegx$#",
86	0
87};
88