summaryrefslogtreecommitdiff
path: root/sysdeps/unix/sysv/linux/s390/sysconf.c
blob: d6a9c81ff02e01ec237b4a1276ae9cc8655380c6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
/* Get system parameters, e.g. cache information.  S390/S390x version.
   Copyright (C) 2015-2016 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library.  If not, see
   <http://www.gnu.org/licenses/>.  */

#include <unistd.h>
#include <dl-procinfo.h>

static long int linux_sysconf (int name);

/* Possible arguments for get_cache_info.
   The values are reflecting the level/attribute/type indications
   of ecag-instruction (extract cpu attribue).  */
#define CACHE_LEVEL_MAX        8
#define CACHE_ATTR_LINESIZE    1
#define CACHE_ATTR_SIZE        2
#define CACHE_ATTR_ASSOC       3
#define CACHE_TYPE_DATA        0
#define CACHE_TYPE_INSTRUCTION 1

static long
get_cache_info (int level, int attr, int type)
{
  unsigned long int val;
  unsigned int cmd;
  unsigned long int arg;

  /* Check arguments.  */
  if (level < 1 || level > CACHE_LEVEL_MAX
      || attr < CACHE_ATTR_LINESIZE || attr > CACHE_ATTR_ASSOC
      || type < CACHE_TYPE_DATA || type > CACHE_TYPE_INSTRUCTION)
    return 0L;

  /* Check if ecag-instruction is available.
     ecag - extract CPU attribute (only in zarch; arch >= z10; in as 2.24)  */
  if (!(GLRO (dl_hwcap) & HWCAP_S390_STFLE)
#if !defined __s390x__
      || !(GLRO (dl_hwcap) & HWCAP_S390_ZARCH)
      || !(GLRO (dl_hwcap) & HWCAP_S390_HIGH_GPRS)
#endif /* !__s390x__ */
      )
    {
      /* stfle (or zarch, high-gprs on s390-32) is not available.
	 We are on an old machine. Return 256byte for LINESIZE for L1 d/i-cache,
	 otherwise 0.  */
      if (level == 1 && attr == CACHE_ATTR_LINESIZE)
	return 256L;
      else
	return 0L;
    }

  /* Store facility list and check for z10.
     (see ifunc-resolver for details)  */
  register unsigned long reg0 __asm__("0") = 0;
#ifdef __s390x__
  unsigned long stfle_bits;
# define STFLE_Z10_MASK (1UL << (63 - 34))
#else
  unsigned long long stfle_bits;
# define STFLE_Z10_MASK (1ULL << (63 - 34))
#endif /* !__s390x__ */
  __asm__ __volatile__(".machine push"        "\n\t"
		       ".machinemode \"zarch_nohighgprs\"\n\t"
		       ".machine \"z9-109\""  "\n\t"
		       "stfle %0"             "\n\t"
		       ".machine pop"         "\n"
		       : "=QS" (stfle_bits), "+d" (reg0)
		       : : "cc");

  if (!(stfle_bits & STFLE_Z10_MASK))
    {
      /* We are at least on a z9 machine.
	 Return 256byte for LINESIZE for L1 d/i-cache,
	 otherwise 0.  */
      if (level == 1 && attr == CACHE_ATTR_LINESIZE)
	return 256L;
      else
	return 0L;
    }

  /* Check cache topology, if cache is available at this level.  */
  arg = (CACHE_LEVEL_MAX - level) * 8;
  __asm__ __volatile__ (".machine push\n\t"
			".machine \"z10\"\n\t"
			".machinemode \"zarch_nohighgprs\"\n\t"
			"ecag %0,%%r0,0\n\t"   /* returns 64bit unsigned integer.  */
			"srlg %0,%0,0(%1)\n\t" /* right align 8bit cache info field.  */
			".machine pop"
			: "=&d" (val)
			: "a" (arg)
			);
  val &= 0xCUL; /* Extract cache scope information from cache topology summary.
		   (bits 4-5 of 8bit-field; 00 means cache does not exist).  */
  if (val == 0)
    return 0L;

  /* Get cache information for level, attribute and type.  */
  cmd = (attr << 4) | ((level - 1) << 1) | type;
  __asm__ __volatile__ (".machine push\n\t"
			".machine \"z10\"\n\t"
			".machinemode \"zarch_nohighgprs\"\n\t"
			"ecag %0,%%r0,0(%1)\n\t"
			".machine pop"
			: "=d" (val)
			: "a" (cmd)
			);
  return val;
}

long int
__sysconf (int name)
{
  if (name >= _SC_LEVEL1_ICACHE_SIZE && name <= _SC_LEVEL4_CACHE_LINESIZE)
    {
      int level;
      int attr;
      int type;

      switch (name)
	{
	case _SC_LEVEL1_ICACHE_SIZE:
	  level = 1;
	  attr = CACHE_ATTR_SIZE;
	  type = CACHE_TYPE_INSTRUCTION;
	  break;
	case _SC_LEVEL1_ICACHE_ASSOC:
	  level = 1;
	  attr = CACHE_ATTR_ASSOC;
	  type = CACHE_TYPE_INSTRUCTION;
	  break;
	case _SC_LEVEL1_ICACHE_LINESIZE:
	  level = 1;
	  attr = CACHE_ATTR_LINESIZE;
	  type = CACHE_TYPE_INSTRUCTION;
	  break;

	case _SC_LEVEL1_DCACHE_SIZE:
	  level = 1;
	  attr = CACHE_ATTR_SIZE;
	  type = CACHE_TYPE_DATA;
	  break;
	case _SC_LEVEL1_DCACHE_ASSOC:
	  level = 1;
	  attr = CACHE_ATTR_ASSOC;
	  type = CACHE_TYPE_DATA;
	  break;
	case _SC_LEVEL1_DCACHE_LINESIZE:
	  level = 1;
	  attr = CACHE_ATTR_LINESIZE;
	  type = CACHE_TYPE_DATA;
	  break;

	case _SC_LEVEL2_CACHE_SIZE:
	  level = 2;
	  attr = CACHE_ATTR_SIZE;
	  type = CACHE_TYPE_DATA;
	  break;
	case _SC_LEVEL2_CACHE_ASSOC:
	  level = 2;
	  attr = CACHE_ATTR_ASSOC;
	  type = CACHE_TYPE_DATA;
	  break;
	case _SC_LEVEL2_CACHE_LINESIZE:
	  level = 2;
	  attr = CACHE_ATTR_LINESIZE;
	  type = CACHE_TYPE_DATA;
	  break;

	case _SC_LEVEL3_CACHE_SIZE:
	  level = 3;
	  attr = CACHE_ATTR_SIZE;
	  type = CACHE_TYPE_DATA;
	  break;
	case _SC_LEVEL3_CACHE_ASSOC:
	  level = 3;
	  attr = CACHE_ATTR_ASSOC;
	  type = CACHE_TYPE_DATA;
	  break;
	case _SC_LEVEL3_CACHE_LINESIZE:
	  level = 3;
	  attr = CACHE_ATTR_LINESIZE;
	  type = CACHE_TYPE_DATA;
	  break;

	case _SC_LEVEL4_CACHE_SIZE:
	  level = 4;
	  attr = CACHE_ATTR_SIZE;
	  type = CACHE_TYPE_DATA;
	  break;
	case _SC_LEVEL4_CACHE_ASSOC:
	  level = 4;
	  attr = CACHE_ATTR_ASSOC;
	  type = CACHE_TYPE_DATA;
	  break;
	case _SC_LEVEL4_CACHE_LINESIZE:
	  level = 4;
	  attr = CACHE_ATTR_LINESIZE;
	  type = CACHE_TYPE_DATA;
	  break;

	default:
	  level = 0;
	  attr = 0;
	  type = 0;
	  break;
	}

      return get_cache_info (level, attr, type);
    }

  return linux_sysconf (name);
}

/* Now the generic Linux version.  */
#undef __sysconf
#define __sysconf static linux_sysconf
#include <sysdeps/unix/sysv/linux/sysconf.c>