xref: /openbmc/linux/lib/raid6/s390vx.uc (revision 1c2dd16a)
1/*
2 * raid6_vx$#.c
3 *
4 * $#-way unrolled RAID6 gen/xor functions for s390
5 * based on the vector facility
6 *
7 * Copyright IBM Corp. 2016
8 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
9 *
10 * This file is postprocessed using unroll.awk.
11 */
12
13#include <linux/raid/pq.h>
14#include <asm/fpu/api.h>
15
16asm(".include \"asm/vx-insn.h\"\n");
17
18#define NSIZE 16
19
20static inline void LOAD_CONST(void)
21{
22	asm volatile("VREPIB %v24,7");
23	asm volatile("VREPIB %v25,0x1d");
24}
25
26/*
27 * The SHLBYTE() operation shifts each of the 16 bytes in
28 * vector register y left by 1 bit and stores the result in
29 * vector register x.
30 */
31static inline void SHLBYTE(int x, int y)
32{
33	asm volatile ("VAB %0,%1,%1" : : "i" (x), "i" (y));
34}
35
36/*
37 * For each of the 16 bytes in the vector register y the MASK()
38 * operation returns 0xFF if the high bit of the byte is 1,
39 * or 0x00 if the high bit is 0. The result is stored in vector
40 * register x.
41 */
42static inline void MASK(int x, int y)
43{
44	asm volatile ("VESRAVB	%0,%1,24" : : "i" (x), "i" (y));
45}
46
47static inline void AND(int x, int y, int z)
48{
49	asm volatile ("VN %0,%1,%2" : : "i" (x), "i" (y), "i" (z));
50}
51
52static inline void XOR(int x, int y, int z)
53{
54	asm volatile ("VX %0,%1,%2" : : "i" (x), "i" (y), "i" (z));
55}
56
57static inline void LOAD_DATA(int x, int n, u8 *ptr)
58{
59	typedef struct { u8 _[16*n]; } addrtype;
60	register addrtype *__ptr asm("1") = (addrtype *) ptr;
61
62	asm volatile ("VLM %2,%3,0,%r1"
63		      : : "m" (*__ptr), "a" (__ptr), "i" (x), "i" (x + n - 1));
64}
65
66static inline void STORE_DATA(int x, int n, u8 *ptr)
67{
68	typedef struct { u8 _[16*n]; } addrtype;
69	register addrtype *__ptr asm("1") = (addrtype *) ptr;
70
71	asm volatile ("VSTM %2,%3,0,1"
72		      : "=m" (*__ptr) : "a" (__ptr), "i" (x), "i" (x + n - 1));
73}
74
75static inline void COPY_VEC(int x, int y)
76{
77	asm volatile ("VLR %0,%1" : : "i" (x), "i" (y));
78}
79
80static void raid6_s390vx$#_gen_syndrome(int disks, size_t bytes, void **ptrs)
81{
82	struct kernel_fpu vxstate;
83	u8 **dptr, *p, *q;
84	int d, z, z0;
85
86	kernel_fpu_begin(&vxstate, KERNEL_VXR);
87	LOAD_CONST();
88
89	dptr = (u8 **) ptrs;
90	z0 = disks - 3;		/* Highest data disk */
91	p = dptr[z0 + 1];	/* XOR parity */
92	q = dptr[z0 + 2];	/* RS syndrome */
93
94	for (d = 0; d < bytes; d += $#*NSIZE) {
95		LOAD_DATA(0,$#,&dptr[z0][d]);
96		COPY_VEC(8+$$,0+$$);
97		for (z = z0 - 1; z >= 0; z--) {
98			MASK(16+$$,8+$$);
99			AND(16+$$,16+$$,25);
100			SHLBYTE(8+$$,8+$$);
101			XOR(8+$$,8+$$,16+$$);
102			LOAD_DATA(16,$#,&dptr[z][d]);
103			XOR(0+$$,0+$$,16+$$);
104			XOR(8+$$,8+$$,16+$$);
105		}
106		STORE_DATA(0,$#,&p[d]);
107		STORE_DATA(8,$#,&q[d]);
108	}
109	kernel_fpu_end(&vxstate, KERNEL_VXR);
110}
111
112static void raid6_s390vx$#_xor_syndrome(int disks, int start, int stop,
113					size_t bytes, void **ptrs)
114{
115	struct kernel_fpu vxstate;
116	u8 **dptr, *p, *q;
117	int d, z, z0;
118
119	dptr = (u8 **) ptrs;
120	z0 = stop;		/* P/Q right side optimization */
121	p = dptr[disks - 2];	/* XOR parity */
122	q = dptr[disks - 1];	/* RS syndrome */
123
124	kernel_fpu_begin(&vxstate, KERNEL_VXR);
125	LOAD_CONST();
126
127	for (d = 0; d < bytes; d += $#*NSIZE) {
128		/* P/Q data pages */
129		LOAD_DATA(0,$#,&dptr[z0][d]);
130		COPY_VEC(8+$$,0+$$);
131		for (z = z0 - 1; z >= start; z--) {
132			MASK(16+$$,8+$$);
133			AND(16+$$,16+$$,25);
134			SHLBYTE(8+$$,8+$$);
135			XOR(8+$$,8+$$,16+$$);
136			LOAD_DATA(16,$#,&dptr[z][d]);
137			XOR(0+$$,0+$$,16+$$);
138			XOR(8+$$,8+$$,16+$$);
139		}
140		/* P/Q left side optimization */
141		for (z = start - 1; z >= 0; z--) {
142			MASK(16+$$,8+$$);
143			AND(16+$$,16+$$,25);
144			SHLBYTE(8+$$,8+$$);
145			XOR(8+$$,8+$$,16+$$);
146		}
147		LOAD_DATA(16,$#,&p[d]);
148		XOR(16+$$,16+$$,0+$$);
149		STORE_DATA(16,$#,&p[d]);
150		LOAD_DATA(16,$#,&q[d]);
151		XOR(16+$$,16+$$,8+$$);
152		STORE_DATA(16,$#,&q[d]);
153	}
154	kernel_fpu_end(&vxstate, KERNEL_VXR);
155}
156
157static int raid6_s390vx$#_valid(void)
158{
159	return MACHINE_HAS_VX;
160}
161
162const struct raid6_calls raid6_s390vx$# = {
163	raid6_s390vx$#_gen_syndrome,
164	raid6_s390vx$#_xor_syndrome,
165	raid6_s390vx$#_valid,
166	"vx128x$#",
167	1
168};
169