1/* -*- linux-c -*- ------------------------------------------------------- *
2 *
3 *   Copyright 2002 H. Peter Anvin - All Rights Reserved
4 *
5 *   This program is free software; you can redistribute it and/or modify
6 *   it under the terms of the GNU General Public License as published by
7 *   the Free Software Foundation, Inc., 53 Temple Place Ste 330,
8 *   Boston MA 02111-1307, USA; either version 2 of the License, or
9 *   (at your option) any later version; incorporated herein by reference.
10 *
11 * ----------------------------------------------------------------------- */
12
13/*
14 * raid6/mmx.c
15 *
16 * MMX implementation of RAID-6 syndrome functions
17 */
18
19#ifdef CONFIG_X86_32
20
21#include <linux/raid/pq.h>
22#include "x86.h"
23
24/* Shared with raid6/sse1.c */
25const struct raid6_mmx_constants {
26	u64 x1d;
27} raid6_mmx_constants = {
28	0x1d1d1d1d1d1d1d1dULL,
29};
30
31static int raid6_have_mmx(void)
32{
33	/* Not really "boot_cpu" but "all_cpus" */
34	return boot_cpu_has(X86_FEATURE_MMX);
35}
36
37/*
38 * Plain MMX implementation
39 */
40static void raid6_mmx1_gen_syndrome(int disks, size_t bytes, void **ptrs)
41{
42	u8 **dptr = (u8 **)ptrs;
43	u8 *p, *q;
44	int d, z, z0;
45
46	z0 = disks - 3;		/* Highest data disk */
47	p = dptr[z0+1];		/* XOR parity */
48	q = dptr[z0+2];		/* RS syndrome */
49
50	kernel_fpu_begin();
51
52	asm volatile("movq %0,%%mm0" : : "m" (raid6_mmx_constants.x1d));
53	asm volatile("pxor %mm5,%mm5");	/* Zero temp */
54
55	for ( d = 0 ; d < bytes ; d += 8 ) {
56		asm volatile("movq %0,%%mm2" : : "m" (dptr[z0][d])); /* P[0] */
57		asm volatile("movq %mm2,%mm4");	/* Q[0] */
58		for ( z = z0-1 ; z >= 0 ; z-- ) {
59			asm volatile("movq %0,%%mm6" : : "m" (dptr[z][d]));
60			asm volatile("pcmpgtb %mm4,%mm5");
61			asm volatile("paddb %mm4,%mm4");
62			asm volatile("pand %mm0,%mm5");
63			asm volatile("pxor %mm5,%mm4");
64			asm volatile("pxor %mm5,%mm5");
65			asm volatile("pxor %mm6,%mm2");
66			asm volatile("pxor %mm6,%mm4");
67		}
68		asm volatile("movq %%mm2,%0" : "=m" (p[d]));
69		asm volatile("pxor %mm2,%mm2");
70		asm volatile("movq %%mm4,%0" : "=m" (q[d]));
71		asm volatile("pxor %mm4,%mm4");
72	}
73
74	kernel_fpu_end();
75}
76
77const struct raid6_calls raid6_mmxx1 = {
78	raid6_mmx1_gen_syndrome,
79	NULL,			/* XOR not yet implemented */
80	raid6_have_mmx,
81	"mmxx1",
82	0
83};
84
85/*
86 * Unrolled-by-2 MMX implementation
87 */
88static void raid6_mmx2_gen_syndrome(int disks, size_t bytes, void **ptrs)
89{
90	u8 **dptr = (u8 **)ptrs;
91	u8 *p, *q;
92	int d, z, z0;
93
94	z0 = disks - 3;		/* Highest data disk */
95	p = dptr[z0+1];		/* XOR parity */
96	q = dptr[z0+2];		/* RS syndrome */
97
98	kernel_fpu_begin();
99
100	asm volatile("movq %0,%%mm0" : : "m" (raid6_mmx_constants.x1d));
101	asm volatile("pxor %mm5,%mm5");	/* Zero temp */
102	asm volatile("pxor %mm7,%mm7"); /* Zero temp */
103
104	for ( d = 0 ; d < bytes ; d += 16 ) {
105		asm volatile("movq %0,%%mm2" : : "m" (dptr[z0][d])); /* P[0] */
106		asm volatile("movq %0,%%mm3" : : "m" (dptr[z0][d+8]));
107		asm volatile("movq %mm2,%mm4"); /* Q[0] */
108		asm volatile("movq %mm3,%mm6"); /* Q[1] */
109		for ( z = z0-1 ; z >= 0 ; z-- ) {
110			asm volatile("pcmpgtb %mm4,%mm5");
111			asm volatile("pcmpgtb %mm6,%mm7");
112			asm volatile("paddb %mm4,%mm4");
113			asm volatile("paddb %mm6,%mm6");
114			asm volatile("pand %mm0,%mm5");
115			asm volatile("pand %mm0,%mm7");
116			asm volatile("pxor %mm5,%mm4");
117			asm volatile("pxor %mm7,%mm6");
118			asm volatile("movq %0,%%mm5" : : "m" (dptr[z][d]));
119			asm volatile("movq %0,%%mm7" : : "m" (dptr[z][d+8]));
120			asm volatile("pxor %mm5,%mm2");
121			asm volatile("pxor %mm7,%mm3");
122			asm volatile("pxor %mm5,%mm4");
123			asm volatile("pxor %mm7,%mm6");
124			asm volatile("pxor %mm5,%mm5");
125			asm volatile("pxor %mm7,%mm7");
126		}
127		asm volatile("movq %%mm2,%0" : "=m" (p[d]));
128		asm volatile("movq %%mm3,%0" : "=m" (p[d+8]));
129		asm volatile("movq %%mm4,%0" : "=m" (q[d]));
130		asm volatile("movq %%mm6,%0" : "=m" (q[d+8]));
131	}
132
133	kernel_fpu_end();
134}
135
136const struct raid6_calls raid6_mmxx2 = {
137	raid6_mmx2_gen_syndrome,
138	NULL,			/* XOR not yet implemented */
139	raid6_have_mmx,
140	"mmxx2",
141	0
142};
143
144#endif
145