summaryrefslogtreecommitdiffstats
path: root/arch/s390/kernel/cache.c
blob: 4f266903022091921be3fd97c200f4210627a948 (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
// SPDX-License-Identifier: GPL-2.0
/*
 * Extract CPU cache information and expose them via sysfs.
 *
 *    Copyright IBM Corp. 2012
 */

#include <linux/seq_file.h>
#include <linux/cpu.h>
#include <linux/cacheinfo.h>
#include <asm/facility.h>

enum {
	CACHE_SCOPE_NOTEXISTS,
	CACHE_SCOPE_PRIVATE,
	CACHE_SCOPE_SHARED,
	CACHE_SCOPE_RESERVED,
};

enum {
	CTYPE_SEPARATE,
	CTYPE_DATA,
	CTYPE_INSTRUCTION,
	CTYPE_UNIFIED,
};

enum {
	EXTRACT_TOPOLOGY,
	EXTRACT_LINE_SIZE,
	EXTRACT_SIZE,
	EXTRACT_ASSOCIATIVITY,
};

enum {
	CACHE_TI_UNIFIED = 0,
	CACHE_TI_DATA = 0,
	CACHE_TI_INSTRUCTION,
};

struct cache_info {
	unsigned char	    : 4;
	unsigned char scope : 2;
	unsigned char type  : 2;
};

#define CACHE_MAX_LEVEL 8
union cache_topology {
	struct cache_info ci[CACHE_MAX_LEVEL];
	unsigned long raw;
};

static const char * const cache_type_string[] = {
	"",
	"Instruction",
	"Data",
	"",
	"Unified",
};

static const enum cache_type cache_type_map[] = {
	[CTYPE_SEPARATE] = CACHE_TYPE_SEPARATE,
	[CTYPE_DATA] = CACHE_TYPE_DATA,
	[CTYPE_INSTRUCTION] = CACHE_TYPE_INST,
	[CTYPE_UNIFIED] = CACHE_TYPE_UNIFIED,
};

void show_cacheinfo(struct seq_file *m)
{
	struct cpu_cacheinfo *this_cpu_ci;
	struct cacheinfo *cache;
	int idx;

	this_cpu_ci = get_cpu_cacheinfo(cpumask_any(cpu_online_mask));
	for (idx = 0; idx < this_cpu_ci->num_leaves; idx++) {
		cache = this_cpu_ci->info_list + idx;
		seq_printf(m, "cache%-11d: ", idx);
		seq_printf(m, "level=%d ", cache->level);
		seq_printf(m, "type=%s ", cache_type_string[cache->type]);
		seq_printf(m, "scope=%s ",
			   cache->disable_sysfs ? "Shared" : "Private");
		seq_printf(m, "size=%dK ", cache->size >> 10);
		seq_printf(m, "line_size=%u ", cache->coherency_line_size);
		seq_printf(m, "associativity=%d", cache->ways_of_associativity);
		seq_puts(m, "\n");
	}
}

static inline enum cache_type get_cache_type(struct cache_info *ci, int level)
{
	if (level >= CACHE_MAX_LEVEL)
		return CACHE_TYPE_NOCACHE;
	ci += level;
	if (ci->scope != CACHE_SCOPE_SHARED && ci->scope != CACHE_SCOPE_PRIVATE)
		return CACHE_TYPE_NOCACHE;
	return cache_type_map[ci->type];
}

static inline unsigned long ecag(int ai, int li, int ti)
{
	return __ecag(ECAG_CACHE_ATTRIBUTE, ai << 4 | li << 1 | ti);
}

static void ci_leaf_init(struct cacheinfo *this_leaf, int private,
			 enum cache_type type, unsigned int level, int cpu)
{
	int ti, num_sets;

	if (type == CACHE_TYPE_INST)
		ti = CACHE_TI_INSTRUCTION;
	else
		ti = CACHE_TI_UNIFIED;
	this_leaf->level = level + 1;
	this_leaf->type = type;
	this_leaf->coherency_line_size = ecag(EXTRACT_LINE_SIZE, level, ti);
	this_leaf->ways_of_associativity = ecag(EXTRACT_ASSOCIATIVITY, level, ti);
	this_leaf->size = ecag(EXTRACT_SIZE, level, ti);
	num_sets = this_leaf->size / this_leaf->coherency_line_size;
	num_sets /= this_leaf->ways_of_associativity;
	this_leaf->number_of_sets = num_sets;
	cpumask_set_cpu(cpu, &this_leaf->shared_cpu_map);
	if (!private)
		this_leaf->disable_sysfs = true;
}

int init_cache_level(unsigned int cpu)
{
	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
	unsigned int level = 0, leaves = 0;
	union cache_topology ct;
	enum cache_type ctype;

	if (!this_cpu_ci)
		return -EINVAL;
	ct.raw = ecag(EXTRACT_TOPOLOGY, 0, 0);
	do {
		ctype = get_cache_type(&ct.ci[0], level);
		if (ctype == CACHE_TYPE_NOCACHE)
			break;
		/* Separate instruction and data caches */
		leaves += (ctype == CACHE_TYPE_SEPARATE) ? 2 : 1;
	} while (++level < CACHE_MAX_LEVEL);
	this_cpu_ci->num_levels = level;
	this_cpu_ci->num_leaves = leaves;
	return 0;
}

int populate_cache_leaves(unsigned int cpu)
{
	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
	struct cacheinfo *this_leaf = this_cpu_ci->info_list;
	unsigned int level, idx, pvt;
	union cache_topology ct;
	enum cache_type ctype;

	ct.raw = ecag(EXTRACT_TOPOLOGY, 0, 0);
	for (idx = 0, level = 0; level < this_cpu_ci->num_levels &&
	     idx < this_cpu_ci->num_leaves; idx++, level++) {
		if (!this_leaf)
			return -EINVAL;
		pvt = (ct.ci[level].scope == CACHE_SCOPE_PRIVATE) ? 1 : 0;
		ctype = get_cache_type(&ct.ci[0], level);
		if (ctype == CACHE_TYPE_SEPARATE) {
			ci_leaf_init(this_leaf++, pvt, CACHE_TYPE_DATA, level, cpu);
			ci_leaf_init(this_leaf++, pvt, CACHE_TYPE_INST, level, cpu);
		} else {
			ci_leaf_init(this_leaf++, pvt, ctype, level, cpu);
		}
	}
	this_cpu_ci->cpu_map_populated = true;
	return 0;
}