xref: /openbmc/linux/arch/s390/lib/xor.c (revision 9a29f5fc)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Optimized xor_block operation for RAID4/5
4  *
5  * Copyright IBM Corp. 2016
6  * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
7  */
8 
9 #include <linux/types.h>
10 #include <linux/export.h>
11 #include <linux/raid/xor.h>
12 #include <asm/xor.h>
13 
14 static void xor_xc_2(unsigned long bytes, unsigned long * __restrict p1,
15 		     const unsigned long * __restrict p2)
16 {
17 	asm volatile(
18 		"	larl	1,2f\n"
19 		"	aghi	%0,-1\n"
20 		"	jm	3f\n"
21 		"	srlg	0,%0,8\n"
22 		"	ltgr	0,0\n"
23 		"	jz	1f\n"
24 		"0:	xc	0(256,%1),0(%2)\n"
25 		"	la	%1,256(%1)\n"
26 		"	la	%2,256(%2)\n"
27 		"	brctg	0,0b\n"
28 		"1:	ex	%0,0(1)\n"
29 		"	j	3f\n"
30 		"2:	xc	0(1,%1),0(%2)\n"
31 		"3:\n"
32 		: : "d" (bytes), "a" (p1), "a" (p2)
33 		: "0", "1", "cc", "memory");
34 }
35 
36 static void xor_xc_3(unsigned long bytes, unsigned long * __restrict p1,
37 		     const unsigned long * __restrict p2,
38 		     const unsigned long * __restrict p3)
39 {
40 	asm volatile(
41 		"	larl	1,2f\n"
42 		"	aghi	%0,-1\n"
43 		"	jm	3f\n"
44 		"	srlg	0,%0,8\n"
45 		"	ltgr	0,0\n"
46 		"	jz	1f\n"
47 		"0:	xc	0(256,%1),0(%2)\n"
48 		"	xc	0(256,%1),0(%3)\n"
49 		"	la	%1,256(%1)\n"
50 		"	la	%2,256(%2)\n"
51 		"	la	%3,256(%3)\n"
52 		"	brctg	0,0b\n"
53 		"1:	ex	%0,0(1)\n"
54 		"	ex	%0,6(1)\n"
55 		"	j	3f\n"
56 		"2:	xc	0(1,%1),0(%2)\n"
57 		"	xc	0(1,%1),0(%3)\n"
58 		"3:\n"
59 		: "+d" (bytes), "+a" (p1), "+a" (p2), "+a" (p3)
60 		: : "0", "1", "cc", "memory");
61 }
62 
63 static void xor_xc_4(unsigned long bytes, unsigned long * __restrict p1,
64 		     const unsigned long * __restrict p2,
65 		     const unsigned long * __restrict p3,
66 		     const unsigned long * __restrict p4)
67 {
68 	asm volatile(
69 		"	larl	1,2f\n"
70 		"	aghi	%0,-1\n"
71 		"	jm	3f\n"
72 		"	srlg	0,%0,8\n"
73 		"	ltgr	0,0\n"
74 		"	jz	1f\n"
75 		"0:	xc	0(256,%1),0(%2)\n"
76 		"	xc	0(256,%1),0(%3)\n"
77 		"	xc	0(256,%1),0(%4)\n"
78 		"	la	%1,256(%1)\n"
79 		"	la	%2,256(%2)\n"
80 		"	la	%3,256(%3)\n"
81 		"	la	%4,256(%4)\n"
82 		"	brctg	0,0b\n"
83 		"1:	ex	%0,0(1)\n"
84 		"	ex	%0,6(1)\n"
85 		"	ex	%0,12(1)\n"
86 		"	j	3f\n"
87 		"2:	xc	0(1,%1),0(%2)\n"
88 		"	xc	0(1,%1),0(%3)\n"
89 		"	xc	0(1,%1),0(%4)\n"
90 		"3:\n"
91 		: "+d" (bytes), "+a" (p1), "+a" (p2), "+a" (p3), "+a" (p4)
92 		: : "0", "1", "cc", "memory");
93 }
94 
95 static void xor_xc_5(unsigned long bytes, unsigned long * __restrict p1,
96 		     const unsigned long * __restrict p2,
97 		     const unsigned long * __restrict p3,
98 		     const unsigned long * __restrict p4,
99 		     const unsigned long * __restrict p5)
100 {
101 	asm volatile(
102 		"	larl	1,2f\n"
103 		"	aghi	%0,-1\n"
104 		"	jm	3f\n"
105 		"	srlg	0,%0,8\n"
106 		"	ltgr	0,0\n"
107 		"	jz	1f\n"
108 		"0:	xc	0(256,%1),0(%2)\n"
109 		"	xc	0(256,%1),0(%3)\n"
110 		"	xc	0(256,%1),0(%4)\n"
111 		"	xc	0(256,%1),0(%5)\n"
112 		"	la	%1,256(%1)\n"
113 		"	la	%2,256(%2)\n"
114 		"	la	%3,256(%3)\n"
115 		"	la	%4,256(%4)\n"
116 		"	la	%5,256(%5)\n"
117 		"	brctg	0,0b\n"
118 		"1:	ex	%0,0(1)\n"
119 		"	ex	%0,6(1)\n"
120 		"	ex	%0,12(1)\n"
121 		"	ex	%0,18(1)\n"
122 		"	j	3f\n"
123 		"2:	xc	0(1,%1),0(%2)\n"
124 		"	xc	0(1,%1),0(%3)\n"
125 		"	xc	0(1,%1),0(%4)\n"
126 		"	xc	0(1,%1),0(%5)\n"
127 		"3:\n"
128 		: "+d" (bytes), "+a" (p1), "+a" (p2), "+a" (p3), "+a" (p4),
129 		  "+a" (p5)
130 		: : "0", "1", "cc", "memory");
131 }
132 
133 struct xor_block_template xor_block_xc = {
134 	.name = "xc",
135 	.do_2 = xor_xc_2,
136 	.do_3 = xor_xc_3,
137 	.do_4 = xor_xc_4,
138 	.do_5 = xor_xc_5,
139 };
140 EXPORT_SYMBOL(xor_block_xc);
141