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/sse1.c
15 *
16 * SSE-1/MMXEXT implementation of RAID-6 syndrome functions
17 *
18 * This is really an MMX implementation, but it requires SSE-1 or
19 * AMD MMXEXT for prefetch support and a few other features. The
20 * support for nontemporal memory accesses is enough to make this
21 * worthwhile as a separate implementation.
22 */
23
24 #ifdef CONFIG_X86_32
25
26 #include <linux/raid/pq.h>
27 #include "x86.h"
28
29 /* Defined in raid6/mmx.c */
30 extern const struct raid6_mmx_constants {
31 u64 x1d;
32 } raid6_mmx_constants;
33
raid6_have_sse1_or_mmxext(void)34 static int raid6_have_sse1_or_mmxext(void)
35 {
36 /* Not really boot_cpu but "all_cpus" */
37 return boot_cpu_has(X86_FEATURE_MMX) &&
38 (boot_cpu_has(X86_FEATURE_XMM) ||
39 boot_cpu_has(X86_FEATURE_MMXEXT));
40 }
41
42 /*
43 * Plain SSE1 implementation
44 */
raid6_sse11_gen_syndrome(int disks,size_t bytes,void ** ptrs)45 static void raid6_sse11_gen_syndrome(int disks, size_t bytes, void **ptrs)
46 {
47 u8 **dptr = (u8 **)ptrs;
48 u8 *p, *q;
49 int d, z, z0;
50
51 z0 = disks - 3; /* Highest data disk */
52 p = dptr[z0+1]; /* XOR parity */
53 q = dptr[z0+2]; /* RS syndrome */
54
55 kernel_fpu_begin();
56
57 asm volatile("movq %0,%%mm0" : : "m" (raid6_mmx_constants.x1d));
58 asm volatile("pxor %mm5,%mm5"); /* Zero temp */
59
60 for ( d = 0 ; d < bytes ; d += 8 ) {
61 asm volatile("prefetchnta %0" : : "m" (dptr[z0][d]));
62 asm volatile("movq %0,%%mm2" : : "m" (dptr[z0][d])); /* P[0] */
63 asm volatile("prefetchnta %0" : : "m" (dptr[z0-1][d]));
64 asm volatile("movq %mm2,%mm4"); /* Q[0] */
65 asm volatile("movq %0,%%mm6" : : "m" (dptr[z0-1][d]));
66 for ( z = z0-2 ; z >= 0 ; z-- ) {
67 asm volatile("prefetchnta %0" : : "m" (dptr[z][d]));
68 asm volatile("pcmpgtb %mm4,%mm5");
69 asm volatile("paddb %mm4,%mm4");
70 asm volatile("pand %mm0,%mm5");
71 asm volatile("pxor %mm5,%mm4");
72 asm volatile("pxor %mm5,%mm5");
73 asm volatile("pxor %mm6,%mm2");
74 asm volatile("pxor %mm6,%mm4");
75 asm volatile("movq %0,%%mm6" : : "m" (dptr[z][d]));
76 }
77 asm volatile("pcmpgtb %mm4,%mm5");
78 asm volatile("paddb %mm4,%mm4");
79 asm volatile("pand %mm0,%mm5");
80 asm volatile("pxor %mm5,%mm4");
81 asm volatile("pxor %mm5,%mm5");
82 asm volatile("pxor %mm6,%mm2");
83 asm volatile("pxor %mm6,%mm4");
84
85 asm volatile("movntq %%mm2,%0" : "=m" (p[d]));
86 asm volatile("movntq %%mm4,%0" : "=m" (q[d]));
87 }
88
89 asm volatile("sfence" : : : "memory");
90 kernel_fpu_end();
91 }
92
93 const struct raid6_calls raid6_sse1x1 = {
94 raid6_sse11_gen_syndrome,
95 NULL, /* XOR not yet implemented */
96 raid6_have_sse1_or_mmxext,
97 "sse1x1",
98 1 /* Has cache hints */
99 };
100
101 /*
102 * Unrolled-by-2 SSE1 implementation
103 */
raid6_sse12_gen_syndrome(int disks,size_t bytes,void ** ptrs)104 static void raid6_sse12_gen_syndrome(int disks, size_t bytes, void **ptrs)
105 {
106 u8 **dptr = (u8 **)ptrs;
107 u8 *p, *q;
108 int d, z, z0;
109
110 z0 = disks - 3; /* Highest data disk */
111 p = dptr[z0+1]; /* XOR parity */
112 q = dptr[z0+2]; /* RS syndrome */
113
114 kernel_fpu_begin();
115
116 asm volatile("movq %0,%%mm0" : : "m" (raid6_mmx_constants.x1d));
117 asm volatile("pxor %mm5,%mm5"); /* Zero temp */
118 asm volatile("pxor %mm7,%mm7"); /* Zero temp */
119
120 /* We uniformly assume a single prefetch covers at least 16 bytes */
121 for ( d = 0 ; d < bytes ; d += 16 ) {
122 asm volatile("prefetchnta %0" : : "m" (dptr[z0][d]));
123 asm volatile("movq %0,%%mm2" : : "m" (dptr[z0][d])); /* P[0] */
124 asm volatile("movq %0,%%mm3" : : "m" (dptr[z0][d+8])); /* P[1] */
125 asm volatile("movq %mm2,%mm4"); /* Q[0] */
126 asm volatile("movq %mm3,%mm6"); /* Q[1] */
127 for ( z = z0-1 ; z >= 0 ; z-- ) {
128 asm volatile("prefetchnta %0" : : "m" (dptr[z][d]));
129 asm volatile("pcmpgtb %mm4,%mm5");
130 asm volatile("pcmpgtb %mm6,%mm7");
131 asm volatile("paddb %mm4,%mm4");
132 asm volatile("paddb %mm6,%mm6");
133 asm volatile("pand %mm0,%mm5");
134 asm volatile("pand %mm0,%mm7");
135 asm volatile("pxor %mm5,%mm4");
136 asm volatile("pxor %mm7,%mm6");
137 asm volatile("movq %0,%%mm5" : : "m" (dptr[z][d]));
138 asm volatile("movq %0,%%mm7" : : "m" (dptr[z][d+8]));
139 asm volatile("pxor %mm5,%mm2");
140 asm volatile("pxor %mm7,%mm3");
141 asm volatile("pxor %mm5,%mm4");
142 asm volatile("pxor %mm7,%mm6");
143 asm volatile("pxor %mm5,%mm5");
144 asm volatile("pxor %mm7,%mm7");
145 }
146 asm volatile("movntq %%mm2,%0" : "=m" (p[d]));
147 asm volatile("movntq %%mm3,%0" : "=m" (p[d+8]));
148 asm volatile("movntq %%mm4,%0" : "=m" (q[d]));
149 asm volatile("movntq %%mm6,%0" : "=m" (q[d+8]));
150 }
151
152 asm volatile("sfence" : :: "memory");
153 kernel_fpu_end();
154 }
155
156 const struct raid6_calls raid6_sse1x2 = {
157 raid6_sse12_gen_syndrome,
158 NULL, /* XOR not yet implemented */
159 raid6_have_sse1_or_mmxext,
160 "sse1x2",
161 1 /* Has cache hints */
162 };
163
164 #endif
165